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SECOND DRAFT

REPORT OF THE TASK TEAM OF EXPERTS ON

EFFECTS OF CLIMATIC CHANGES IN THE

SOUTH EAST PACIFIC REGION

United Nations Environment Programe - UNEP ComisiGn permanente del Pacífico Sur - CPPS

Intergovernmental Oceanographic Commission - IOC

TASK TEAM OF EXPERTS FROM THE SOUTH EAST PACIFIC REGION

CHILE : Sergio Avaria

Patricio Berna1

Flarco A. Retama1

Rosa Aguilera

COLONBIA : Carlos Barreto

Gustavo Polo

ECUADOR : bilio Cucalón

Alexandra Cedeño

PAN AMA : Luis DtCroz

PERU : Manuel Florez

Luis Acosta

k' i th the Collaboration o£ : David Enfield - NOAA - Miami

Co-ordinator : J. J. Escobar Ramírez

Consultant

UhW/CPPS South East Pacific Action Plan

TABLE OF CONTENTS

Foreword

Introduction

CHAPTER 1. 1mpl.ications of Climatic Changes in the South 1 East Pacif ic

Physical Aspects 1

CHAPTER 11. Implications of Climatic Changes on Key Marine Ecosystems in the South East Pacific

1. Coral Reefs

2. Mangroves

3. Coastal Pelagic Ecosystems

4. Bentic Environment

5. Estuarine Ecosystems

CHAPTER 111. Impact on Key Terrestrial Coastal Ecosystems in the South East Pacific

1. Forests

2. Fiairies

3. Hydrographic Basins

CHAPTER IV. Impact of Climatic Changes on Fisheries Along The South East Pacific

1. Fish

2. Crustacean

3. Mollusks

4. Algae

5. Birds

6. Marnmals

CHAPTER V. Socio-Economic Impact of Climatic Changes in the South East Pacific

CHAPTER VI, Impact on the Continental Coastal Zone - Productive Sectors : Agriculture, Cattle, Silviculture, Forestry

1. Climatic Changes

2. Sea Leve1 Increase

CHAPTER VII. Institutional Aspects

AMNEX The 1982-1983 " E l Niño" Phenomenon in the South East Pacific : A Case Study.

As a response to the concern expressed in certain regions about the possible implications o£ expected climatic changes (mostly man-induced) in the rnarine and coastal environment, the UKEP has initiated the preparation of studies which would review the situation in the various regions covered by the Regional Seas Programne. This Report is the assessment of the South East Pacific region and includes the impact on the Pacific Coast of Colombia, Chile, Ecuador, Panarna and Peru as well as the "El Niño" Phenonenon as a case study.

The study covers the marine environment and adjacent coastal areas i n f l d by or havíng an influence upon the marine environment. The proposed objectives of this study are the following :

a) to look into the possible effects of sea leve1 changes on the coastal ecosystems (deltas, estuaries, wetlands, coastal plains, coral reefs, rnangroves, etc.).

b) to inquire about the possible effects of tenperature elevations on the terrestrial and aquatic ecosystems, including the possible effects of siich changes on economically important species;

c) to examine the possible effects of climatic, physiographic and ecological changes on socio-economic structures and activities;

and

d) to determine areas or systems which would appear to be most vulnerable to tiie above mentioned changes.

A Task Team of Experts was set up to elaborate on the analysis of the objectives stated above. The Permanent South Pacific Conmission,as Regional Co-ordinating Unit o£ the Action Plan for the Protection of the llarine Environment and Coastal Areas of the South East Pacific, in consultations with the IOC and UIjEP, invited a selected group of experts from the region's countries to participate in the preparation of this regional study.A meeting of the Task Team was held in Bogotá (Colombia) from 30th Xovember to 2nd December 1987. The meeting adopted a work schedule to review the regional situation as regards the implications of climatic changes considering, as starting point, the effects of such changes which have been linked to the occurrence of the "El Niño" Phenomenon the resulting effects o£ which are considered in this Regional Report.

The v a r i o u s o u t l o o k s borne i n mind i n t h i s r e g i o n a l r e v i e w have been addresced by r e g i o n a l e x p e r t s i n d i f f e r e n t s c i e n t i f i c f i e l d s such as n a r i n e b i o l o g y , o c e a n o g r a p h y , e c o l o g y , meteoro logy , h y d r o l o g y , economics , e t c . , on t h e b a s i s o f a l a r g e nunber o f s c i e n t i f i c and t e c h n i c a l c o n t r i b u t i o n s ; most o f s u c h c o n t r i b u t i o n s r e f e r t o t h e Reg iona l S tudy o f t h e "El Niño" Phenomenon - ERFEN, t o t h e i d e n t i f i c a t i o n and a s s e s s m e n t o£ t h e d i f f e r e n t i n p l i c a t i o n s o f clirriatic c h a n g e s on t h e r e g i o n a l e c o s y s t e n c and socio-economic s t r u c t u r e s .

I t h a s been w i d e l y a c c e p t e d t h a t t h e q u e s t i o n o£ f o r e c a s t i n g c l i m a t i c c h a n g e s is c l o s e l y a s s o c i a t e d w i t h t h e d e t e r m i n a t i o n o f p h y s i c a l c a u s e s a c c o u n t i n g f o r them. On t h e l o n g t e r m t h e emphas i s h a s been made on t h e v a r i a t i o n s o b s e r v e d i n Coa c o n c e n t r a t i o n s . The a s s e s s m e n t o f r e c e n t r e s u l t s on t h e b a s i s o f c l i m a t i c models shows t h a t t h e i n c r e a s e o f t h e e a r t h ' s mean s u r f a c e t e m p e r a t u r e d u e t o a n i n c r e a s e of COZ and o t h e r "gieenhouse" g a s e s e q u i v a l e n t t o t w i c e t h e c u r r e n t a t m o s p h e r i c c o n c e n t r a t i o n o f c a r b o n d i o x i d e c o u l d v a r y f rom 1.5OC t o 4.5OC, showing h i g h e r v a l u e s a t h í g h a l t i t u d e s (Charney, 1979; Smagor insky , 1982). By comparison, d u r i n g t h e I c e ' Age t h e world mean tern e r a t u r e was 5" - 6OC c o l d e r t h a n t h e c u r r e n t t e m p e r a t u r e T i t u s , 1986). It Kas been e s t i m a t e d t h a t by y e a r 2.030 t h i s h e a t i n g c o u l b- r e p r e s e ñ f a l.S°C i n c r e a s e i n t h e mean s u r f a c e t e m p e r a t u r e . T h i s p r o j e c t e d wor ld h e a t i n g would r e s u l t , on i ts t u r n , i n t h e a c c e l e r a t i o n o f t h e c u r r e n t rate o f e l e v a t - i o n o f t h e mean s e a l e v e l due t o t h e e x p a n s i o n o f o c e a n i c water, t h e thawing o f g l a c i e r s a n d , e v e n t u a l l y , would c a u s e t h e thawing o r s l i d i n g o f p o l a r ice l a y e r s t o w a r d s t h e ocean. The thawing and s l i d i n g o f Gree land and A n t a r c t i c ice c a p s a c c o u n t f o r more t h a n 50% o f t h e e l e v a t i o n o f t h e mean sea1 l e v e l d u r i n g t h e l a s t f o r t y y e a r s (12 cm). I n l i k e manner, it h a s been s t a t e d t h a t t h e thawing and s l i d i n g o£ t h e A n t a r c t i c i ce c a p would r e s u l t i n a n i n c r e a s e i n t h e novement o f t h e e a r t h ( r e p r e s e n t e d by t h e de- c e l e r a t i o n i n t h e r o t a t i o n a l speed and a t i n y i n c r e a s e i n t h e d a y ' s l e n g t h (SCOR/IOC, 1982) . -- - Corcplying w i t h t h e recor rnenda t ions o f t h e V i l l a c h 1985 Meet ing , t h e UNEP h a s e n b a r k e d i n t h e w r i t i n g u p o£ r e p o r t s on t h e p o s s i b l e e f f e c t s o f c l i m a t i c c h a n g e s on rnar ine and c o a s t a l ecosys tems . T h i s s t u d y is b e i n g c a r r i e d o u t i n t h e v a r i o u s r e g i o n s i n v o l v e d i n t h e R e g i o n a l S e a s P r o g r a m e . I:'ithin t h e f r a n e w o r k o f t h e L%EP p r o j e c t , t h e P e r n a n e n t Sou th P a c i f i c C o m i s s i o n , as R e g i o n a l C o - o r d i n a t i n g U n i t o f t h e A c t i o n P l a n o f t h e Sou th E a s t P a c i f i c , c o u n t i n g on t h e s u p p o r t o f UNEP and IOC i n v i t e d a group o£ r e g i o n a l e x p e r t s t o g a t h e r t o g e t h e r i n Bogotá , from 3 0 t h November t o 2nd Decernber 1987 t o se t up a T a s k Team whose j o b would be t o p r e p a r e t h e r e p o r t on t h e S o u t h E a s t P a c i f i c r e g i o n .

The Group dec ided t o adopt t h e same recornmendations i s s u e d by t h e V i l l a c h meet ing a s g u i d e l i n e s f o r t h e p r e p a r a t i o n o f t h e Regiona l Repor t , i.e.,

a) Sea S u r f a c e Temperature (SST) = I n c r e a s e s of 1.5OC up t o y e a r 2.025, on t h e b a s i s of l a t i t u d i n a l v a r i a t i o n s ; and

b) R e l a t i v e Sea Level (RSL) = I n c r e a s e s of 20 cms. up t o y e a r 2.025. .*

The Group was o f t h e op in ion t h a t "El Niño" Phenomenon r e p r e s e n t s one of t h e most s i g n i f i c a n t r e g i o n a l e v e n t s o c c u r r i n g i n t h e ocean and i n t h e a tmosphere , one having an ou t s t and ing impact on t h e c l i m a t e and t h e mar ine environrnent; t h e r e f o r e , t h e Group decided t o i n c l u d e t h e 1982-1983 "El Niño" Phenomenon i n t h e Regional Report a s a c a s e s t u d y t o show t h e sho r t - t e rm

j e f f e c t s o f c l i r n a t i c chanpes i n t h e South E a s t P a c i f i c . There e x i s t sound C r e a s o n s t o c a r r y on a s tudy of t h e "El Niño" Phenonenon n o t w i t h s t a n d i n g

t h e f a c t t h a t t h e phenomenon does n o t occur on a t i m e scale w i t h i n a long- term c l i m a t i c change. To e v e n t u a l l y come t o unde r s t and t h e c a u s e s t h a t g i v e o r i g i n t o "El Xiño" could a l l o v u s t o have an i n k l i n g on how ocean c i r c u l a t - i o n cou ld r e a c t t o f u t u r e changes i n t h e r o r l d h e a t i n g ba l ance .

The E Niño" Phenomenon h a s been regarded as t h e ' occu r r ence a l o n g t h e c o a s t a l areas o£ Ecuador, Peru and C h i l e o£ a l a r g e scale anomaly i n t h e oceanic-a tmospher ic i n t e r a c t i o n (Wyrtky, - 1982), mainly a f f e c t i n g t h e P a c i f i c Ecuador ian s t r i p and i . lvo lv ing most o f t h e world r e g i o n s (Rasmusson and \a!allace, 1983). T h i s c o a s t a l phenomenon r e a c h e s d r a m a t i c p r o p o r t i o n s i n t h e a r e a s f a c i n g t h e c o a s t a l r e g i o n s o f some c o u n t r i e s of t h e South E a s t P a c i f i c Systern showing p o s i t i v e tempera ture anoma l i e s i n a r a n g e of 2OC t o 3OC above t h e s u r f a c e mean t e n p e r a t u r e a s w e l l as i n c r e a s e s i n t h e sea mean l e v e 1 o f up t o 40 cms and a maximum of 50 c m s as r eco rded d u r i n g t h e 1983 Phenomenon (Fonsece -e' - 1985). The re fo re , we may assume t h a t t h e e f f e c t s s u s t a i n e d by t h e variol*; r e g i o n a l ecosystems and socio-economic s t r u c t u r e s d u r i n g t h e e v e n t s may, i n t h e shor t - te rm, r e f l e c t t h o s e t o occu r i n y e a r 2.025.

BIRLIOGRAPHY

Aubrey D.G. 1955, Recent Sea Leve ls from Tide Gauges : Problems and Prognos is . I n Keier M. F., G l a c i e r s , Ice S h e e t s and Sea Leve l , Y a t i o n a l Academy of Sc ience Press, Washington, D.E., 73-91.

Charney J., 1979, Carbon Dioxide and Cl imate : A S c i e n t i f i c Assessment, Repor t of t h e -- Ad hoc Study Group on Carbon Dioxide and Cl imate . N a t i o n a l Research Counci l , Na t iona l Academy P i e s s , Washington,D.C

-

Fonseca R.T., 1985, E fec tos F í s i c o s d e l Fenómeno E l Niño 1982-1983 e n l a .. . Cos ta Chilena. En : T a l l e r I lacional Fenómeno E l Riño 1952-1983,

Número E s p e c i a l pub. I n s t . de I n v e s t i g a c i o n e s Pesque ra s , C h i l e , Inv. Pesqu. ( C h i l e ) 32, 61 - 68.

. . - i v -

Gorni tz V. and Lebedeff , 1987, Global Sea Level Changes dur ing t h e Past Century. I n : Kurnmendal, D. O. H. Pi lkey and J. D. Howard (eds ) , Sea Level Fluctuat ion and Coas ta l Evolution. Soc ie ty o£ Economic P a l e o n t o l o g i s t and f l ine rea log i s t , Spec. Pub. 140. 41, Tulsa , Oklahoma, 3 - 16.

Hoffman, J.S., J. B. Well and J. G. T i t u s , 1986. Future Global llarming and Sea Level Rise. I n : Eruun P. (ed) Ice land Symposium, 1985, Ka t iona l Energy Authori ty, Reykjavik.

Ramusson, E.M. and J .M. Kallace, 1983. Meteorological Aspects of E l Niño/ rrc -f---..l-- Southern O s c i l l a t i o n , Scíence , 222(4629) : 1195 - 1202.

Smagorinsky, J. 1982 : Carbon Dioxide : A Second Assessment, Nat ional Academy P r e s s , l*!ashington, D. C.

SCOR/IOC, 1982, Sumrnary Report - Third Sess ion, S p l i t , 1-5 March, 1982 on C o ~ m i t t e e on Clirriate Changes and t h e Ocean; Intergovernrnental Oceanographic Commission/Scientific Committee on Oceanic Research Doc. SCOR-IOC/CCCO-11113, P a r i s , Mayo 7 , 36-37.

T i t u s , J . G . , 1956, Greenhouse E f f e c t , Sea Level Rise and Coas ta l Zone Manage- ment J o u r n a l , 14; 147-171.

Wyrtkn K . , 1982, The Southern O s c i l l a t i o n , Ocean-Atmosphere I n t e r a c t i o n and E l Niño, Mar, Tech, Soc J. 16(1):3 - 10.

CHAPTER 1

IMPLICATIONS OF CLIMATIC CHANGES IN THE


Physical Aspects

The most strongly felt impact of a sea level rise is the flooding of those areas located right above the original water level. These areas, known as "wetlands" are usually found at altitudes below the yearly highest tide and above sea level. Therefore, "wetlandsf' account for the largest land areas located at less than 1 metre above sea level.

Flooding depends on the gradient immediately above the original sea level alone. Due to the fact that the shore profiles are usually flatter than the shore land right above sea level, the erosion resulting from a sea level rise covers an area larger than the land beins directly affected by the flood (Bruun -* - 1962). It has been widely recognized that a sea leve1 rise equivalent to 1 cm. would result in a 1 m. landward retreat of the coastline (Rruun P. 1962). Nevertheless, this effect has a stronger impact along the coast bathed by larger size waves; in some instances, the coastline may show a landward retreat of 2 - 4 m. by each cm. of sea level rise (Army,1979). The potential erosion of the coastal zone resulting from a sea level rise could have a meaningful impact on recreational beaches. Considering that only a few of the regionfs most developed bathing places have access to a beach area of less than 20 m. during the high .tide, the 20 cm. sea level rise being forecast for year 2.025 would erode most recreational beaches in developed- areas. Northein Peru can be quoted as an example of these ef f ects. Al%,ph&

Besides, the sea level rise could increase the damage produced by floodings and tidal waves in coastal areas. Three factors should be considered mainly: The resulting erosion would increase the vulnerability of some cornmunities to withstand the dashing of large waves; high water levels would supply waves with a highest base on which to grow; higher water levels would, therefore, affect natural and man-made drainage systems. Thus, a 20 cm. sea level rise could severely impair certain protective structures during a period of strong wave motion due to the higher sea level and to the larger size o£ waves resulting from the erosion of sand submerged in front of the structure (Kyper and Sorensen, - 1985).

Notuithstanding the fact that the emphasis has been made mainly on the gl~bai sea level projections, the impact in certain areas will also depend on the relative sea level. Some of the factors influencing the local sea level and which could change as a result of the global warming up include : (hrents, winds and the flow of rivers into the estuaries. Nevertheless, none of these possible impacts has been calculated so far. The ever increasing warming up of the Earth surface as projected within the next few decades implies as well a rise of the sea subsurface temperature and the subsequent expansion of ocean water thus resulting in an additional sea level rise.

S i m u l t a n e o u s t o t h e c h a n g e s s u s t a i n e d by t h e ocean i n terms o f h e a t and w a t e r c o n t e n t i n t h e s u r f a c e l a y e r , t h e r e o c c u r s a change i n t h e o c e a n ' s d e n s i t y . The r e s u l t i n g t h e r m a l c i r c u l a t i o n w i l l r e f l e c t t h e s e c h a n g e s i n i ts c o n t r i b u t i o n t o t h e g l o b a l r e d i s t r i b u t i o n o f h e a t and w a t e r .

A s f a r as t h e P a c i f i c B a s i n is concerned , s t o r m s and h u r r i c a n e s d e v e l o p i n t h e c e n t r a l and w e s t e r n r e g i o n s g i v i n g o r i g i n t o l a r g e - s i z e d waves (swells) which on many i n s t a n c e s r e a c h t h e S o u t h Arnerican w e s t e r n c o a s t a f f e c t i n g i ts morphology. \:!hat is more, a more f r e q u e n t t r e n d i n t h e occur - r e n c e o f s t o r m s would t e n d t o making t h e t y p i c a l s h o r e p r o f i l e e v e n f l a t t e r r e s u l t i n g i n a s u b s t a n t i a l landward r e t r e a t o f t h e c o a s t a l l i n e . C o n t r a r y t o t h e above and on i ts t u r n , a d e c r e a s i n g t r e n d i n t h e f r e q u e n c y o f w i n t e r s t o r m s c o u l d have a n opposed impact a t h i g h e r l a t i t u d e s .

Due t o t h e f a c t t h a t warmer t e m p e r a t u r e s would i n t e n s i f y t h e h y d r o l o g i c a l c y c l e , i t h a s been e s t i m a t e d t h a t a g l o b a l warming up would r e s u l t i n a change i n t h e r a i n f a l l p a t t e r n w i t h r a i n b e i n g h e a v i e r i n come areas t h a n i n o t h e r s .

N o t w i t h s t a n d i n g t h a t most r e s e a r c h e r s have f o c u s e d t h e i r c o n c e r n upon t h e i n c r e a s e o f f l o o d i n g s and t h e landward retreat o f t h e c o a s t a l l i n e a s s o c i a t e d w i t h a r i c e i n t h e sea l e v e l , t h e i n l a n d p e n e t r a t i o n o f s a l t y water c o u l d have a s i g n i f i c a n t e f f e c t i n some areas. A r ise i n t h e sea l e v e l would i n c r e a s e t h e s a l i n i t y rates of some e s t u a r i e s t h e r e b y a l t e r i n g t h e b a l a n c e between t h e f r e s h water and s a l t y w a t e r powers o f s t r e n g t h . A rice o f t h e sea l e v e l h a s a n i m p a c t similar t o t h a t o f a d e c r e a s e o f t h e f r e s h w a t e r i n f l o w : By e n l a r g i n g and deepening t h e e s t u a r y , t h e r ise o f t h e sea l e v e l i n c r e a s e s t h e a b i l i t y o f t h e s a l t y w a t e r t o b e conveyed ups t ream.

The most c o p h i s t i c a t e d modcls c u r r e n t l y i n u s e are u n a b l e t o a c c u r a t e l y p o i n t o u t l o c a l o r r eg ionr .1 anomal ies p r e s e n t i n t h e c o a s t a l c i r c u l a t i o n and r e s u l t i n g f rom t h e p r a j e c t e d changes i n t e m p e r a t u r e and s e a ' l e v e l . T h i s i s m a i n l y d u e - t o t h e h i g h l e v e l s o f n a t u r a l v a r i a b i l i t y and t h e c o n s e q u e n t i a l l a r g e amount o f s i m u l a t i o n r e q u i r e d t o r e a c h s t a t i s t i c a l l y m e a n i n g f u l r e s u l t s .

To c o n c l u d e , we must a n t i c i p a t e t h a t o u r climate and n a t u r a l env i ronment would be s u b j e c t e d t o c h a n g e s beyond h i s t o r i c a l e x p e r i e n c e . Our d e s c e n d a n t s w i l l h a v e t o d e v e l o p new d e f i n i t i o n s o f what is "normalf1, t h e y w i l l have t o a d j u s t t h e i r e x p e c t a t i o n s as r e g a r d s f l o o d i n g s and d r o u g h t s , and t h e y w i l l h a v e t o rnodify t h e i r food and w a t e r s o u r c e s . Some o f t h e e x p e c t e d c h a n g e s may be b e n e f i c i a l , some o t h e r s may be harmfu l ; still some o t h e r s may b e u n c o n s e q u e n t i a l . N ~ t ~ i t h s t a n d i n g , u n l e s s t h e s e c h a n g e s are t i m e l y p e r c e i v e d and u n d e r s t o o d , most o f them w i l l p robab ly be h a r m f u l . A t l e a s t we must t r y and set up t h e ground b a s i s o f knowledge and u n d e r s t a n d i n g upon which o u r d e s c e n d a n t s rnay act.

BIRLIOGRAPHY

U.S. Army Corps of Engineers, 1979, Ocean Beach Study : F e a s i b i l i t y Report. San Francisco : Corps o£ Engineers. 1979.

ERWN P. 1962, Sea Level Rise as a Cause o£ Shore Erosion. Journa l of Water- :/ ways and Harbor Division. (ASLE) 1: 116 - 130.

IXPER T., and R. SORENSEN, 1985; P o t e n t i a l Impacts of Se lec ted Sea Leve l Rise Scenar ios on t h e Beach and Coasta l Works a t Sea Br igh t New Jersey . En : Coastal .Zone, 85, eds. 0. I.Zagoon e t a l .

R I N D R. , and S. LEBEDEFF 1984; P o t e n t i a l Climate Impacts of I n c r e a s i n g Atrnospheric CO, with Emphasis on Water A v a i l a b i l i t y and Hydrology i n t h e Vnited S t a t e s . Washington, D.C.

CHAPTER 11

IMPLICATIONS OF CLIMATIC CHANGES

ON KEY MARINE ECOSYSTEMS I N THE

SOLJTH EAST PACIFIC REGION

1. C o r a l Reefs

C o r a l r e e f s are of f r e q u e n t o c c y u e n c e i n t h e E a s t P a ~ i f i c . ~ j w ~ * J ~ S c i e n t i f i c l i t e r a t u r e abound i n d e s c r i p t i o n s o f c o r a l r e e f s and a s s o c i a t e d comxun i t i e s i n Cos ta Rica,. Panama, -C-olombia a n d - of CCXQEL, . . Malpelo and Galapagos. Gene ra l l y speaking , c o r a l r e e f s p r e s e n t i n t h e r e g i o n are c h a r a c t e r i z e d b x . che- re l -a- t jvely-smal l .n i lmh d a e m (from 8 t o 10 S-pec ies by r e e f ) , Amongst t h e s e s p e c i e s , p o c i l o p o r i d e r e e f s p r e v a i l . C o r a l r e e f s t h r i v e i n p r o t e c t e d , sha l low w a t e r s , a t a dep th of no more t h a n 10 t o 1 5 m. . The presence of co ld water a r i s i n g frorn t h e Peru- v i a n c u r r e n t , c o a s t a l ou t c ropp ings , h i g h t u r b i d i t y r a t e s of water i n t h e a r e a s c l o s e to t h e c o a s t r e s u l t i n g from t h e ou t f l owing of a l a r g e number o f r i v e r s and t h e wide t i d a l range seem t o be accoun tab l e f o r r e s t r i c t i n g t h e d i s t r i b u t i o n o f r e e f s i n t h e r e g i o n and a r e a l s o r e s p o n s i b l e f o r t h e i r s m a l l size and d i s c o n t i n u i t y (Glynn, 1982; Glynn, Von P r a h l and Gulh, 1983).

P a l e o b i o l o g i c a l i n f o r m a t i o n a v a i l a b l e s u g g e s t s t h a t du r ing t h e P l i o c e n e and t h e Quaternary p e r i o d s t h e r e occur red changes i n t h e sea l e v e l and t h e t empera tu re o f t h e sea w h i c b favoured t h e growth and d i s t r i b u t i o n o£ reefs i n g e n e r a l (I4ells -9 - 1956) ;- l ~ h e r e f o r e , a 20 cm. i n c r e a s e i n t h e sea l e v e 1 does n o t seem t o be t h e l i k e ' j r ea son f o r t h e oy , cu~f"~&f&+~- r r e v e r s g l e changes i n t h e South E a s t P r z i f i c c o r a l r e e f s d Changes s u s t a m e d Ty t h e t empera tu re cou ld e n t a i l a s i g n i f i c a n t outcorne (Dana -9 - 1975). A 1.5OC i n c r e a s e i n t h e s e a s u r f a c e t empera tu re rcay favour t h e growth and d i s t r i b u t i o n o f t h o s e r e e f s c u r r e n t l y t h r i v i n g c l o s e t o t h e low t empera tu re (20°C) t o l e r a n c e l i m i t , as is t h e case w i t h t h o s e r e e f s growing n e a r ou t c ropp ing a r e a s or co ld c u r r e n t s . The r e e f s found n e a r t h e P e r l a s I s l a n d s , i n t h e Panarna G u l f , f i t t h i s d e s c r i p t i o n ; t h e y a r e a f f e c t e d by p e r i o d i c a l ou t c ropp ings . The sarile a p p l i e s t o r e e f s p r e s e n t i n t h e Galapagos I s l a n d s . For t h o s e r e e f s s u b j e c t e d t o u s u a l l y h i g h t e n p e r a t u r e s (28 t o 2g°C), such a s t h e r e e f s found around t h e Gorgona I s l a n d s i n Colombia, and t h e Secas , Uvas and C o n t r e r a s I s l a n d s i n t h e C h i r i q u í Gulf (Ponama) a 1.5OC i n c r e a s e cou ld produce a n e g a t i v e d i s t u r b a n c e . During t h e occu r r ence o f t h e 1982-1983 "El Niño" t h e s e a s u r f a c e t e m p e r a t u r e r o s e up t o sonewhat h i g h e r t h a n 30°C i n s e v e r a 1 a r e a s o£ t h e E a s t P a c i f i c ; as a r e s u l t of t h i s , i n e a r l y 1983 t h e r e were r e p o r t s o f a wh i t en ing of r e e f s due t o t h e e x p e l l i n g of z o o x a n t e l l e s . There- f o r e , it h a s been e s t a b l i s h e d t h a t vhenever t h e s e r e e f s occur i n a r e a s t o o c l o s e t o t h e h i g h e s t t he rma l t o l e r a n c e l i m i t , a 1.5OC rice i n t h e sea s u r f a c e t empera tu re could have ca la rn i tous e f f e c t s .

BIBLIOGRAPHY

DANA T. F., 1975; Developrnent o£ Contemporary Eastern Pacific Coral Reefs. Marine Biology, 33: 335-374.

GLYNN P. W., 1984; Widespread Coral Mortality.and the 1982-83 El Niño Warming Event. Environmental Conservation, 2 ( 2 ) : 133-146.

GLYNN, P. W., 1982; Coral Communities and their Modifications Relative to Past and Prospective Central American Seaways. Advances in blarine Biology, 19: 91-132.

GLYNN, P.W., 1977; Coral Growth in Upwelling and Nonupwelling Areas Off the Pacific Coast o£ Panama. Journal of Harine Research, 35: 567-585

GLYNN P.W. and G. M. \;'ELLINGTON, 1983; Corals and Coral Reefs of the Gala- pagos Islands. Univ. of Calif ornia Press, Eerkeley/Los ~ngeles/ London, 329 pp.

GLYNN P.M., Von PRAHL and F. GUHL, 1982; Coral Reefs of Gorgona Islands, Colombia, with Special Reference to Corallivores and their Influence on Cornrnunity Structure and Reef Development. Anales Instituto de Investigación Marina de Punta Betín, Santa Marta, Colombia, 13: 185 - 214.

\TELLS J.W., 1956; Scleratinia. En "Treatise on Invertebrate Paleontology (R.C. Moore, ed.), Parte F. Coelenterata, pp. 328-444. Geological Society of America, Univ. Kansas Press, Lawrence.

2. Mangroves

The South East Pacific mangrove ecosystem is located in the so called t'wetlands" and is generally made up by Rhyzophorae and Avicennia Luguncularia in an association which varies from place to place. In Panama, Colombia, Ecuador and the northernmost area of Peru, the mangrove forest appears in the shape of a strip of land parallel to the coast which breaks into the mainland in sections of differing thickness. The intrusion of this strip of land is more extended in the Northern region of Ecuador, in some areas of Guayas and in the Southern zone o£ Colombia. The mangrove ecosystem extends itself over 283.775 Ha. in Colombia whilst in Ecuador it covers some 177.755 Ha.

During the 1952-83 "El Niño" event, in some mangrove areas of Northern Peru and Ecuador the sea leve1 reached heights of more than 2 m. above normal. The high temperatures and extremely low salinity rates recorded, which had been cauced by a continuous precipitation during the 1982-83 event, together with a high load of sediments and sludge resulted in high mortality rates of filter mollusks (Anadara grandis, Chione subrugosa, Ostrea SJ) as well as of mangrove crabs (Ucides SJ). 0n the other hand, catch rates of different penides from the mangrove area (Peneus vannamei, bre.virrostris, P califor- niensis, P stylirrostris, Xiphopenaeus rivertii) increased from 70-20 kg/ ~isherman?da~ pre-event to 80-100 kg/f isherman/day during the event.

Tenperature elevations should not have a direct effect on these species given the usual ranges in which they develop. This would imply qualitative changes in the composition of the ecosystem as well as variations in its hiph productivity rates.

3. Coastal Pelagic Ecosystem

The outstanding biological productivity of countries located on the South Fast Pacific coast relies on intensive coastal outbreaks, on the presence o£ a shallow mixture layer and on the occurrence o£ a thermocline close to the surface. These conditions determine an extraordinary wealth of fito- plankton which is reflected in the high yearly produce o£ the ecosystem's whole trophic levels.) Drastic reductions 6f this high productivity occur at intervals between three and ten years as a consequence of changes in the conditions mentioned. These ano,malous conditions are due to the effects of the "El Riño" Phenomenon and result in serious biological sequels mainly recorded in low primary productivity and changes in the cornposition and distribution of species in pelagic communities.

Yielding a primary production higher than 1.000 gr Cm-'/year- l. t& Peruvian current is regarded as the world ' S most productive ecosystem. [~cientif ic evidence on the effects of climatic changes on the basis of those recorded during the "El Niño" Phcnonenon are soundly supported by appropriate refer- ente material in Arntz (1985)l Under "noryil" conditions, values of surface nutrients fluctuate from 10 to 20 ugr at 1- for silicates; from 10 to 15 ugr at 1-1 for nitrates; from 2 to 3 ugr at 1-1 for phosphhtes (Zuts y Guillen, 1970). During the 1982-83 "El Niño" event chlorophyll values ranged from 0.1 to 0.2 ug at 1-1 in Ecuador (ERFEN, -- 1984).' The low chlorophyll values '

suggest the disappearance o£ outbreaking areas during the event, particularly in northern Peru. Under normal conditions in the outbreak area located between 5" and 23OS diatoms thriving in cold water prevail. During the event diatorns are reduced and confined to smaller areas of up to 10 hs. Vnder normal conditions, such areas extend up to 200 Kms. offshoreJ During the event, the neritic area is invaded by tropical and subtropical dinoflagelates as well as by a large number o£ warm water-diatoms. Dinoflagelates replace prevailing diatomc. Some typical invaders are : Ceratium trichocerus, C. carriense and C. gibhrum (Rojas de Mediola et al. 19~5)-.--n and oceanic zooplankton invade outbreak areas from the early stages o£ the event introducing drastic changes in species composition, reducing density rates and increasing diversity.

Alterations in environmental conditions and those changes occurring at lower trophic levels have a serious effect oil the region's pelagic fisheries bring- ing about disorganization of fish schools and changes in species distribution patterns. J

The most dramatic effects of climatic changes associated to "El Niño" were its influence on anchovetta (En~raulis ringens) fisheries. The Peruvian and Chilean 1970 catch amounted to 13 million M' Tons whilst the 1973 catch produce only reached 1.200.000 1.1' Tons. The dramatic reduction of the anchovetta bio~ass produced an ecological vacuum in the ecosystem. Ey diainishing the intake of planlíton 2nd by relaxing the conpetition stress over other related planktophagus species, the expansion of the latter was hastened thereby increasing the biomass o£ sardine (Sardinops sagax), jurel . (Trachurus murphy) and sackerel (Scomber japonicus). This was particularly evident as far as the catch of sardine was concerned since it showed a 150% increase during a ten year period.

S e r i o u s a l t e r a t i o n s i n t h e p h y s i o l o g i c a l f c a t u r e s o f t h e s p e c i e s d u r i n g t h e "El Riño" e v e n t are a l s o t o b e t a k e n i n t o account . Such a l t e r a t i o n s are t o be found i n t h e l o s s o f body w e i g h t due t o t h e d i m i n i s h i n g f a t c o n t e n t . T h i s e f f e c t r ebounds i n t h e f i s h r e d u c i n g i n d u s t r y s i n c e t h e o i l c o n t e n t p e r t o n o f c a t c h i s g r e a t l y reduced . Tn l i k e rnanner, t h e r e p r o d u c t i v e c y c l e of s p e c i e s is a f f e c t e d by a l t e r a t i o n s i n t h e spawning s e a s o n and by l a r v a e and j u v e n i l e m o r t a l i t y which, on i t s t u r n , h a s a n i n f l u e n c e on l a t e r y e a r s ' r e c r u i t m e n t f i g u r e s .

The a n c h o v e t a , which i s t h e s p e c i e s b e t t e r adap ted t o t h e u n u s u a l l y h i g h b i o l o g i c a l p r o d u c t i v i t y o f t h e c o a s t a l p e l a g i c ecosystern and , t h e r e f o r e , t h e s p e c i e s most a f f e c t e d by its c h a n g e s , v i r t u a l l y v a n i s h e d from t h e C h i l e a n c o a s t f rom where i t carne t o show up a g a i n i n r a t h e r r e s t r i c t e d areas o£ t h e P e r u v i a n c o a s t . The change i n t h e f i t o p l a n k t o n c o m p o s i t i o n , f rom t h e p r e v a l e n c e o£ d i a t o m s t o t h a t o f d i n o f l a g e l a t e s , a l t e r e d t h e f e e d i n g h a b i t s o f t h e a n c h o v e t t a and t h e s a r d i n e , t h e r e b y modi fy ing t h e p h y s i o l o g i c a l c o n d i t i o n s o f b o t h s p e c i e s which s u s t a i n e d a lo s s of body w e i g h t o f up t o 302. The j u r e l s p e c i e s widened i ts s c o p e o f l a t i t u d i n a l d i s t r i b u t i o n n o r t h - wards and g a t h e r e d t o g e t h e r a round t h e i n n e r f i f t y miles l e s s e n i n g t h e p r e s s u r e o f f i s h i n g and t h a t o f o c e a n p r e d a t o r s which k e p t c l o s e t o them, s u c h a s t u n a f i s h and s t r i p p e d tunny . '?-?o~c.ever, t h e j u r e l sp . q u i c k l y went back t o f i s h i n g o n c e t h e e v e n t was o v e r t h u s s t r e s s i n g t h e f a c t t h a t it is endowed w i t h t h e power t o e n d u r e t h e most r i g o r o u s phenonena.

The m a c k e r e l s p . a l s o widened its d i s t r i b u t i o n p a t t e r n s and showed a p o s i t i v e r e l a t i o n s h i p between t h e spawning s e a s o n and t h e a l t e r a t i o n o f e n v i r o n m e n t a l c o n d i t i o n s . A l 1 t h r e e s p e c i e s n e n t i o n e d , i.e., s a r d i n e , j u r e l and m a c k e r e l , showed b e t t e r e n d u r a n c e t h a n t h e a n c h o v e t t a sp . t o t h e impac t o f t h e "El Niño" e v e n t .

Due t o t h e c l o s e r e l a t i o n s h i p e x i s t i n g between p e l a g i c f i s h and .guano b i r d s , p o p u l a t i o n f i g u r e s o f t h e la t te r h a v e been s e r i o u s l y i m p a i r e d by t h e climatic c h a n g e s a s s o c i a t e d t o t h e "El I4iño" e v e n t . I n P e r u , t h e p o p u l a t i o n s of f guanay ' ( P h a l a c r o r o r a x b o u p a i n v i l l i ) , ' p i q u e r o ' ( S u l a v a r i e g a ) and P e l i c a n

( P e l e c a n u s o c c i d e n t a l i s ) amounted t o come 30 milli!on b i r d s i n 1950 f i g u r e which by 1982 had been reduced t o 6 m i l l i o n and o n l y 300.000 b i r d s w e r e left a f t e r t h e 1982-83 e v e n t . The d i s a p p e a r a n c e o f t h e t r a d i t i o n a l p e l a g i c t r o p h i c n e t n o t o n l y a f f e c t e d t h e guano b i r d s b u t was a lso r e s p o n s i b l e f o r t h e d e a t h o f seals and t h e l o s s o f n e a r l y a y e a r l y class.

4. R e n t i c Environment

l4ost b e n t i c s p e c i e s t h r i v i n g i n t h e I ? e g i o n t s o u t b r e a k a r e a s are a d a p t e d t o s u s t a i n i n g low te rnpera tu res . \#,%en warm c o n d i t i o n s i n c r e a s e as a r e s u l t : o f t h e "El Kiño" e f f c c t s t h e s e s p e c i e s see t h e m s e l v e s g r e a t l y reduced i n numbers d u e t o m i g r a t i o n and t o t h e d e p r e d a t i o n o f immigran t s p e c i e s f rom xlarm waters a s s i s t e d by h i g h oxggen and t e m p e r a t u r e l e v e l s (Tarazona , 1985)j P o l y c h a e t o s and n e r n e t e o s i n c r e a s e t h e i r b i o n a s s and d e n s i t y t o h e r i l s f rom 50 t o 100 m. i n t h e c e n t r a l c o a s t o f P e r u showing a s u b s t a n t i a l d e c r e a s e d u r i n g t h e e v e n t ' s a c u t e phase. "El YJiño" a l s o h a s a n e f f e c t on t h e be- h a v i o u r a l and d i s t r i b u t i v e p a t t e r n s o f dernersal f i s h . Smal l s c i a n i d e s , p o m a l a s i d e s and o t h e r demersa l s p e c i e s u s u a l l y c a u g h t i n l a r g e q u a n t i t i e s i n t h e G u a y a q u i l Gulf seem t o be a b s e n t d u r i n g t h e e v e n t . A t t h e carne t i m e , l u t j a n i d e s and o t h e r t r o p i c a l f i s h i n v a d e t h e e q u a t o r i a l i a t e r s from t h e Xorth d o ~ m ~ * . a r d s (Tierdson, 1984). I n P e r u , t h e a r e a s o u t h w a r d s of Chimbote, u s u a l l y f i s h scarce, produced l a r g e q u a n t i t i e s o f dog f i s h and ' l o r n a ' d u r i n g t h e 1982-83 "El h'iño" e v e n t . The l a t t e r s p e c i e s showed u n u s u a l b e h a v i o u r f o l l o w i n g a p a t t e r n n e v e r b e f o r e r e c o r d e d : It m i g r a t e d f r o n its t r a d i t i o n a l g r o u n d s 20 kms. o f f t h e s h o r e up t o t h e b o r d e r of t h e c o n t i n e n t a l s h e l f t o d i s t a n c e s of up t o 150 kms. o f f s h o r e , s i r n u l t a n e o u s l y e n l a r g i n g i ts r a n g e o f d i s t r i b u t i o n sou thwards . O t h e r r e c o r d e d m i g r a n t s are t h e swiming c r a b s ( P o r t u n i d a e f a m i l y ) . During t h e e v e n t , t hey n i g r a t e s o u t h w a r d s i n l a r g e numbers r e p r o d u c i n g t h e m s e l v e s o u t s i d e t h e i r u s u a l d i s t r i b u t i o n r a n g e t h u s c r e a t i n g s e r i o u s p rob lems t o f i s h e r i e s . The r o c k l o b s t e r ( P a n u l i r u s gracilis) - o t h e r t r o p i c a l s p e c i e s - i s r a t h e r abun n t d u r i n g t h e " E l Niño" e v e n t i n n o r t h e r n P e r u ( Y o c k t e n ~ e t a l . 1985). "P It h a s a l s o been r e p o r t e d t h a t d u r i n g t h e o c c u r r e n c e o£ t h e e v e n t most c r u s t a c e a n s a u t o c t o n o u s o f t h e o u t - break area s u s t a i n rnzssive n o r t a l i t y . s Ainongst them n e n t i o n s h o u l d be n a d e o£ t h e C a n c e r SJ., P l a t y x a n t h u s o r b i e n y , P e p a t u s =. e t a l .

iu'o sudgen a l t e r a t i o n s i n th> b e n t o n i c e c o s y s t e m c o m p o s i t i o n a r e e x p e c t e d due t o t h e f a c t t h a t most o f i t s s p e c i e s a r e e u r i t h e r m a l , s o t h a t t h e l.S°C h e a t i n c r e a s e f l u c t u a t e s between n o r n a l d i s t r i b u t i v e r a n g e s .

iAn i n c r e a s e i n t h e t e m p e r a t u r e would e n t a i l :

- A d a p t a t i o n o f s u b t i d a l o rgan i sms . - ? : i g r a t i o n o f s t e n o t h e r m a l s u b t i d a l o r g a n i s a s ( r a t h e r s c a r c e o r non

e x i s t e n t ) t o h i g h e r l a t i t u d e s .

- U n i m p o r t a n t e f f e c t s on i n t e r t i d a l o r g a n i s m s g i v e n t h e i r e u r i t h e r n i c c o n d i t i o n .

- T e n p e r a t u r e i n c r e a s e s c o u l d f a v o u r m e t a b o l i c p r o c e s s e s , i.e., growth and spawning.

5. E s t u a r i n e E c o s y s t e ~ s

They a re o n e o f t h e less s t u d i e d e c o s y s t e m s i n L a t i n Amcrica. From t h e e c o l o g i c a l v i e w p o i n t e s t u a r i e s are complex , d i v e r s e and o p e n s y s t e n s rvhich, t o g e t h e r w i t h a h i g h b i o l o g i c a l p r o d u c t i v i t y , o f f e r s h o r t t r o p h i c c h a i n s .

B e t r ~ e e n t h e s o u t h e r n and c e n t r a l areas ( 3 5 O t o 42 's ) t h e C h i l e a n c o a s t d i s - p l a y s e s t u a r i e s l i n l ced t o l a r g e and rnedium s i ze c o a s t a l r i v e r s , some of them s e v e r e l y a f f e c t e d by u r b a n o r i n d u s t r i a l p o l l u t i o n . The s i g n i f i c a n c e o f d e x e r s a l r e s o u r c e s , j o i n e d t o t h e e s t u a r i e s , i n c r c a s e s a l o n g t h e w a t e r w a y s a n d f j i o r d s arca s u p p o r t i n g i m p o r t a n t s h e l l f i s h f i s h e r i e s . I n Co lombia and E c u a d o r m o s t e s t u a r i e s are a s s o c i a t e d t o t h e n a n g r o v e e c o s y s t e m .

An i n c r e a s e i n t h e t e n p e r a t u r e a l s o t r a n s l a t e d i n t o an i n c r e a s e of tbe sea l e v e l would p r o ? u c e a d e c p e r p e n c t r a t i o n o f t h e s a l t y u e 6 g e , p r o d u c i n g a c h a n g e i n t h e n a t u r a l s u c c e s s i o n s o f t h e c c o s y s t e n s p r e v a i l i n g i n t h e e s t u a r y . I n t h e S o u t h East P a c i f i c , c h a n g e s r e c o r d e d d u r i n g t h e "El Kifio" Phenonenon h a v e b e e n a s s o c i a t e d w i t h t h e h i g h p r c c i p i t a t i o n w h i c h r c s u l t s i n f l o o d i n g s , a l t e r a t i o n o f s e d i n e n t a t i o n p a t t e r s a n d rnas s ive n o r t a l i t y o f t h e f a u n a t h r i v i n g i n t h e e s t u a r y . F o r t h e n o s t p a r t , t h e S o u t h E a s t P a c i f i c c o a s t s are low, w i t h s o f t s l o p e s and s o f t s a n d s , i ~ i t h t h e e x 6 e p t i o n o f t h e r e g i o n ' s s o u t h e r n p a r t . An i n c r e a s e i n t h e sea l e v e l i,rould p r o d u c e a l a n d w a r d retreat o f t h e s h o r e l i n e .

CHAPTER 111

I?PACT ON KEY TERRESTRIAL COASTAL ECCSYSTEVS

OF THE SOUTH EAST PACIFIC REGION

391.500.000 Ha. are ded ica t ed t o a g r i c u l t u r a 1 and/or f o r e s t r y r e l a t e d a c t i v i t i e s t h rough t h e South American Andean.region. More t h a n t h r e e - q u a r t e r s of t h i s t e r r i t o r y a r e covered by woody a r e a s and only 82 m i l l i o n Ha. belong t o a g r i c u l t u r a l l y developed l a n d s ; 22 m i l l i o n Ha. of t h i s t o t a l a r e ded ica t ed t o pernanent annua l c r o p s , p r a i r i e s and f a l l owing w h i l s t 60 m i l l i o n Ha. correspond t o n a t i v e p r a i r i e s . 10% of l and under e x p l o i t a t i o n co r r e sponds t o farming l a n d . / -

Ponama : The c o u n t r y e n j o g s 112 km2 of p a s t u r e s l o c a t e d a l o n g s i d e t h e P a c i f í c s lopes . For t h e most p a r t , t h e c o u n t r y ' s p a s t u r e s are nade up by t h e gramineous ' f a r a g u a ' (Hyparhenia r u f a ) .

Colombia : 30.000 Ha. a r e covered by n a t i v e p a s t u r e p r a i r i e s .

Fcuador : 2.0'31.000 Ha. correspond t o farming l ands . ,

Peru : Neasuring 128.522.000 Ha. e x p l o i t s 14.5% of t h e t o t a l f i g u r e ; 61% of t h e s u r f a c e is covered by f o r e s t s o r n a t i v e p a s t u r e s . There are 2.547.000 Ha. ded i ca t ed t o c r o p s which correspond t o 2% of t h e c o u n t r y ' s s u r f a c e .

C h i l e : A g r i c u l t u r a 1 and c a t t l e e x p l o i t a t i o n s account f o r 30.648.700 Ha. 14.7% of which a r e ded ica t ed t o farming l a n d s ; 11.900.000 Ha. are n a t i v e p r a i r i e s and 5.805.600 Ha. a r e f o r e s t s and woodlands. The s u r f a c e p l an t ed w i t h e x o t i c s p e c i e s was i nc reased from 230.000 Ha. i n 1973 t o 1.400.000 Ha. i n 1987 which, added t o t h e n s t i v e f o r e s t , r e p r e s e n t a t o t a l f i g u r e of 9 m i l l i o n Ha.

(Qorectc

I n t h e whole o f Andean America t h e r e a r e more t han 300 m i l l i o n Ha. endowed w i t h f o r e s t s most o£ which are t o be found a t i n a c c e s s i b l e p l a c e s , l o c a t e d i n rough t e r r a i n .

Panama :

For ty p e r c e n t o f t h e count ry shows a f o r e s t e d cove r ing ; t h e n o s t irnport- a n t of t h e s e f o r e s t s a r e t h o s e l o c a t e d i n t h e lowlands of t h e Panamanian P a c i f i c s l o p e s which a r e covered by ' cu ipo ' (Cavani lesa p l a t a n i f o l i a ) i n an e x t e n s i o n e q u i v a l e n t t o 10.000 Km' ; ' c a t i v o ' ( P r i o r i a c o p a i f e r a ) which makes up f o r e s t s , mos t ly monospec i f ic , i n a l l u v i a l l a n d s , o r mixed f o r e s t s , w i t h t h e Mora o l e i f e r a tree i n l a n d s s u b j e c t e d t o t h e i n f l u e n c e o f b r a c k i s h wa te r s . The s i z e covered by t h e s e f o r e s t s h a s been p s t i m a t e d a t 4.000 ~ m ' w h i l s t t h e size o f t h e mangrove f o r e s t s i s o f 5.000 Km .

P e r u : - F o r e s t s of up t o 40 m i n which t h e f o l l o w i n g s p e c i e s p r e v a i l : I fotophagus

s p . , L a u r e l i a s p . , Podocarpus s p . , Keinmania s p . e n t a n g l e d w i t h Chusquea c o v e r a wedge i n t h e Nor th P e r u v i a n Andes. T o g e t h e r w i t h t h e s e s p e c i e s t h e r e a p p e a r t h e s p e c i e s N o t o p h a ~ u s o f a u s t r a l o r i g i n .

C h i l e : - T h e r e are more t h a n 9 m i l l i o n Ha. d e d i c a t e d t o n a t i v e f o r e s t s and 1.4

m i l l i o n Ha. t o e x o t i c s p e c i e s : P i n e ' i n s i g n e ' , e u c a l y p t u s , p o p l a r and A t r i p l e x sp . S t a r t i n g a t 20°L.S. t h e r e a p p e a r s a s n a l l woody mass which d o e s n o t s u r p a s s t h e l o L a t i t u d e . T h i s n a t u r a l r e s o u r c e v a n i s h e s up t o 30°L.S. where it r e a p p e a r s i n t h e s h a p e o£ a n u n e x p l o i t e d n a t i v e f o r e s t a l woody mass and as a r e s o u r c e under e x p l o i t a t i o n i n t h e c o a s t a l area s i t u a t i o n which r e m a i n s up t o 35OL.S. From 36"L.S. onwards t h e r e a r e o n l y man-nade f o r e s t s c o v e r i n g huge areas. The r a t h e r t h i c k n a t i v e v e g e t a t i o n is r e s t r i c t - ed t o t h e Andean Piedrnont and e x t e n d s up t o 54OL.S.

P r o d u c t i v i t y o f some s p e c i e s c u l t i v a t e d i n C h i l e show growth rates o n e - t h i r d h i g h e r t h a n t h o s e o b t a i n e d by t h e b e s t f a r n i n g methods used i n C e n t r a l Europe. These h i g h p r o d u c t i v i t y rates would n o t be a f f e c t e d by c h a n g e s i n t h e t e m p e r a t u r e o f t h e a d j a c e n t c o a s t a l sea; p e r h a p s i t c o u l d p r o j e c t s o u t h w a r d s t h e c u r r e n t d i s t r i b u t i o n o f some xeromorphic s p e c i e s a n d , n o r t h - wards , t h a t o f some a u s t r a l s p e c i e s c u r r e n t l y b e i n g r e s t r i c t e d , as r e g a r d s t h e i r d i s t r i b u t i o n p a t t e r n s , by r a i n f a l l c o n d i t i o n s . P r o d u c t i v i t y o£ some n a t i v e f o r e s t s would n o t be a f f e c t e d by a sea l e v e l r ise w i t h t h e e x c e p t i o n of t h o s e s p e c i e s which grow i n t h e r e g i o n advanc ing f rom t h e sea t o w a r d s t h e Andean Range ( ' c o i g u e ' V a l d i v i a n f o r e s t and ' c h i l o t e ' ) . The e f f e c t on man-made p l a n t a t i o n s would b e less s e r i o u s b e c a u s e , even t h o u g h t h e y advance f rom n e a r t h e c o a s t l i n e , t h e y are c u l t i v a t e d above sea l e v e l . /?

Panama :

Most o f t h e 112 Km2 o f t h e c o u n t r y ' s p a s t u r e s are l o c a t e d on t h e p r a i r i e s a l o n g t h e Panamanian P a c i f i c s l o p e s . Near ly 85X o f t h e s e p r a i r i e s are n a d e up by t h e g ramineous ' f a r a g u a ' (Hyparhenia r u f a ) . T e n p e r a t u r e a l o n e does n o t seem t o have a d i r e c t i n f l u e n c e o v e r t h e c o a s t a l p r a i r i e s e c o s y s t e n s . A sea l e v e l r i c e c o u l d e n l a r g e t h e area a f f e c t e d by f l o o d i n g s t h e r e b y alter- i n g t h e c o m p o s i t i o n and d i s t r i b u t i o n o f c o a s t a l v e g e t a t i o n . It would b e e x p e c t e d t h a t h a l o p h y t i c s p e c i e s p r e v a i l o v e r t h o s e t y p i c a l l y terrestrial. Some s a l i n i t y r e s i s t i n g weeds , s u c h a s Cyperaceae , c o u l d s u s t a i n l a r g e r d i s t r i b u t i o n and growth rates.

Ecuador :

The c o u n t r y shows a c o v e r made up by n a t u r a l p a s t u r e s r e p r e s e n t i n g 1.722.615 Ha. d i s t r i b u t e d i n t h e f o u r c o a s t a l p r o v i n c e s , as f o l l o w s : Guayas: 551.000 Ha.; Manabi 814.000 Ha.; Esmeralda 159.500 Ha.; E l Oro 198.115 Ha. Given t h e e n d u r a n c e o f t h e s e p a s t u r e s t o h i g h t e m p e r a t u r e s and p l u v i a l i n d e x e s , it c o u l d be e x p e c t e d t h a t a lower d e g r e e o f m o i s t u r e i n t h e c o n t i n e n t a l a r e a s o r , a t l e a s t , changes i n t h e r a i n f a l l i n d e x e s , would r e s u l t i n d i f f e r e n t d i s t r i b u t i o n p a t t e r r i s o f t h e p a s t u r e c o v e r i n g . The i n t r u s i o n o f m a r i n e w a t e r s i n t h e c o a s t a l o r r i v e r banks , due t o t h e i n t r u s i o n of s a l t y wedges, c o u l d produce c h a n g e s i n t h e s p e c i f i c cornposi t ion o f p a s t u r e s , p a r t i c u l a r l y n a t i v e o n e s , a l l o w i n g f o r t h e development o f h a l o p h i t e s p e c i e s .

C h i l e :

There e x i s t s a g r e a t v a r i e t y o f p r a i r i e s , b o t h n a t i v e and man-made, i n t h e c o u n t r y ' s m e t r o p o l i t a n r e g i o n s . F a t i v e p r a i r i e s e x i s t i n f i v e r e g i o n s (1 - 11 - VI11 - X I - XII) and man-made p r a r i e s are t o be found i n s e v e n r e g i o n s ( 1 1 1 - I V - V - VI - V I 1 - I X - X ) . A s f a r as a g r i c u l t u r e and f o r e s t - a l a c t i v i t e s a r e concerned i n e a c h Region, t h e V I 1 1 i s d e d i c a t e d t o f o r e s t s , w h i l s t t h e 1, 11, V , V I and XII are d e d i c a t e d t o s h e e p b r e e d i n g a c c o u n t i n g f o r 49X o f t h e c o u n t r y ' s p r o d u c t i o n . G o a t s a r e r a i s e d i n f o u r Reg ions (1 - T I - V and V I ) ; s h e e p i n f i v e Reg ions ( V - V I - VI1 - IX and X) r e p r e s e n t 36.5% o f n a t i o n a l p r o d u c t i o n . Tak ing a d v a n t a g e o f t h e wide v a r i e t y o f micro- c l i m a t e s , t h e I V Region o f f e r s f r u i t and v e g e t a b l e a g r o i n d u s t r i e s . It is q u i t e p o s s i b l e t h a t a n i n c r e a s e i n r a i n f a l l rnay a l l o w f o r t h e deve lopment o£ e x i s t i n g p r a i r i e s c u r r e n t l y r e s t r i c t e d t o w a t e r c o u r s e s and t o t h e c o a s t a l s t r i p u n d e r t h e i n f l u e n c e of t h e 'carnanchaca'.. A h i g h e r r a i n f a l l i n d e x would p roduce a change i n t h e p a s t u r e s s p e c i f i c s t r u c t u r e : f rom x e r o m o r p h i c s p e c i e s t o meso o r hydromorphic s p e c i e s . A sea l e v e l rise s h o u l d a f f e c t e x i s t i n g s p e c i e s , p a r t i c u l a r l y terrestrial o n e s , s i n c e a s a l t y wedge, p a r t i c u l a r l y i n t h e n o r t h e r n zone , would encourage t h e f u r t h e r development ' o f h a l o f i l e s p e c i e s . - - - . - - . . .

H y d r o g r a ~ h i c R a s i n s

Panama :

I n t h e Pananan ian P a c i f i c s l o p e s t h e r e e x i s t s a n e x t e n s i v e d r a i n a g e network i n which t h i r t y - t h r e e h y d r o g r a p h i c b a s i n s map be o b s e r v e d . The y e a r l p a v e r a g e r a i n f a l l washing t h e c o u n t r y amounts t o 233.760 m i l l i o n M'. Some t v e l v e b a s i n s are l o c a t e d i n t h e l o w l a n d s , ve ry c l o s e t o t h e sea a n d , t h e r e f o r e , t h e y may b e s u b j e c t e d t o t h e e f f e c t s o f t h e e n v i r o n m e n t a l c h a n g e s under s t u d y . A sea l e v e l rise may be t h e c a u s e of s i g n i f i c a n t a l t e r a t i o n s due t o a n e n l a r g e m e n t o f t h e s a l t y wedge i n t r u s i o n which, i n come l a r g e r i v e r s , t r a v e l s u p s t r e a m t o a d i s t a n c e o f 20 Km. The l i k e l y c h a n g e s d u e t o a rise i n t h e sea l e v e l c o u l d be t h e f o l l o w i n g :

- H i g h e r s a l i n i t y - Changes i n t h e q u a l i t y o f w a t e r - Changes i n d r a j n e g e p s t t e r n s - Changes i n r i v e r bank v e g e t a t i o n w i t h h i g h m o r t a l i t y rates of

s t e n o h a l i n e s p e c i e s as w e l l as a n i n c r e a s e i n t h e d i s t r i b u t i o n o f e u r i h a l i n e s p e c i e s .

'fie c o u n t r y is eil¿owed w i t h a I a r g e v a r i e t y of h y ü r o g r a p l ~ i c ? ) a s i n s . T h e s e a r e d i s t r i b u t e d i n t h e E s n i e r a l d a s P r o v i n c e and a re fc i r r~ed by t h r c e c n i n s y s t e m s , i .e . : S a n t i a g o C a y a p z s , w i t h a low r i v e r f r e d ; E s n e r a l d a , r e c e i v i n g a l a r s e aiiiount o f d i s c h a r z e s , arid C o j i n i e s , w i t h s e 6 i n e n t s o £ s a n d a n d n u d . T h e r e a r e t w e n t y - s i x r i v e r s i n t h e !-Ianabi T'rovince. The R i v e r Guayas h a s i n is l o c a t e d i n t h e Guapas P r o v i n c e ; t h e b a s i n ' s e x t e n s i o n r u n s f o r 34.000 Km. p r c s e n t i n g a l o w r i v e r b e d and c l a y e d s e d i m e n t s . T h e b a s i n shows a d e e p s a l t y i n t r u s i o n t h r o u g h t h e D a u l e R i v e r wl-iich r e a c h e s a 70 - 80 Km l e n g t h b e t v e e n J u l y and Eecember. S e v e r a l r i v e r s o f v a r i o u s s izes r u n thr-ough t h e E l Oro P r o v i n c e , a l 1 of them o r i g i n a t i n g i n t h e t lndean Yange. %e J u l ~ o n e s P i v e r c o v e r s w i t h i ts s e d i a e n t s a n a r e 2 of 4.285 ha w h i l s t t h e ? . r e n i l l a s R i v e r f l o o d s some 452 ~ m \ n d t h e S a n t a Rosa R i v e r

2 i n u n d a t e s so t i e 955 Km A s u s t a i n e d i n c r e a s e o f t h e sea s u r f a c c t e m p e r a t u r e ::ould g i v e o r i g i n t o heavy r a i n s d u r i n g low r a i n f a l l s e a s o n c t h u s i n c r e a s i n g r i v e r f l o \ c s .

C h i l e :

l i l ong t h e c o u n t r y ' s t w e l v e a d x i n i s t r a t i v e r e g i o n s t h e r e are Eany hydro - g r a p h i c k a s i n s o f d i f f e r e n t s i z e . A r i s e i n t h e t e m p e r a t u r e would i . n c r e a s e t h e r a i n f a l l i n d e x S o t h i n t h e i n t e r m e d i a t e d e p r e s s i o n and i n t h e Andean ?anpe . T h i s i n c r e a s e i n r a i n f a l l would be l i n k e d t o a n i n c r e a s e i n t h a w i n g ~ h i c h , on i ts t u r n , would g r e a t l y c o n t r i b u t e t o t h e a p p e a r a n c e o f l a r g e f l o o r i i n g s a n d l a n d s l i d e s . T h i s i s p a r t i c u l a r l y m e a n i n g f u l f o r C h i l e ' s 1 a n d 11 T s g i o n s w h e r e , d u r i n g t h e d r y s e a s o n t h e r e o c c u r s t h e " p l a t e a u r a i n g s e z s o n " a c c o a p a n i e d by l a r g e r i v e r o v e r f l o w i n g s d u e t o h c a v y r a i n s . The r i c e of t h e sea l e v e 1 \+.ould open t h e a.ay fo r s a l t y wedges t o p e n e t r a t e up- stream a1i;ays d e p e n d i n g on t h e s i z e o f t h e r i v e r f l o w , i t s g r a d i e n t a n d t h e d i f f e r e n c e of no rma l l e v e l . I n some p l a c e s , where t h e i n t r u s i o n t r a v e l s s e v e r a 1 ICE. u p s t r e a m , t h i s would c a c s e t h e e x c h a n g e of t y p j c a l l y e s t u a r i n e s g e c i e s by o t h e r s p e c i e s o f ~ a r i n e o r i g i n .

CHAPTER IV

OF THE SOUTH EAST PACIFIC REGION

The e f f e c t s on f i s h e r i e s of a d r a s t i c change I n some environmental pa rame t r e s r e l a t e d w i t h t h e r e g i o n a l c l i r a t i c c o n d i t i o n s a r e b e s t e l u c i d a t e d by t h e e f f e c t s s u s t n i n e d du r ing t h e 0ccurrcnc:e of t h e 1382-83 "El iíiiío". ' be s t u d y c a r r i e d o u t on t h e Region ' s f i s h i n g a c t i v i t i e s i n d i c a t e d t h a t t h e i r p a c t o f t h e "El Yiño" on t h e South Eas t P a c i f i c f i s h e r i e s h a s been r i j f f c r e n t i n each one of t h e e v e n t s from 1958 a f t e r v a r d s . The 1957-58 cven t had a n e f f e c t on t h e d i s t r i b u t i o n and bc5avjour of t h e anchove t t a . The 1955 c v e n t in t rod i iced ncw changes i n t h e d i s t r i b u t i o n 2nd v u l n e r a b i l i t y of t h e ad,x'-o\?etta and c a t c h e s were s e r i o u s l y i r p a i r e d wi th h a r n f u l e f f e c t s on f i s h e r i e s . The e f f z c t s o f t h e 1972-73 e t ren t were cven c o r e s e r i o u s 2nd l a s t e d r-.~ich l o n g e r : the enchove t t a popu la t i on was g r e a t l y reduced.

The c n l o a d i n g o f f i s h e r i e s produce i n Peru r lur inp yea r 1953 anour-ited t o 1.537.Cl9 Tons e q u i v a l e n t t o t h e l o ~ s e s t eve r r e c o r d obtairtcd s i n c e t h e t i s e i n d u s t r i a l f i s h e r i o s were e s t a b l i s h e d back j n 1959. !!ention should !)e nake o£ t h e f e c t t h a t average c a t c h e s i n normal c l i c a t i c c o n d i t i o n s were i n t h e r e g j o n o f 6 t o 8 m i l l i o n tons /pear . I n 1983, t h e l o s s due t o non- rece ivable

1

incor ,e f o r f i s h p roduc t s anounted t o a p p r o s i ~ a t e l y PSSlOO m i l l i o n .

1. F i s h :

F e l a g i c F i s h : :.lost i x p o r t a n t s p e c i e s are : Anchoveta ( E n p r a u l i s r i n z e n s ) , s a r d i n e (Sard inops s agax ) , J x e l (Trac ' iurus -~ zurpiiy) and l inckere l (Fcomber i apon icus ) . The c a t c h of t h e s e s p e c i e s f o r ycar 1983 anounted t o 1.434.700 Tons (93.5% of t h e t o t a l f i s h c a t c h . T h j s a l l ows us t o c t a t e t h a t a s f a r a s Peru is concerned, t h e i n p a c t o£ t h e 1982-83 "El Niño" Pheno- menon a d v e r s e l y a f f e c t e d t h e a v a i l a b i l i t y of f i s h r e sou rces .

Pnchoveta : A c t i v i t i e s r e l a t e d t o t h e f i s h r e d u c t i o n i n d u s t r y , which s t a r t e d i n 1950, have been suppor t ed , up t o t h e p r e s e n t time, on t h e e x p l o i t a t i o n of t h e anchoveta s p e c i e s . i J eve r the l e s s , w e should p o i n t o u t t h a t a t t h e beginning t h e r e were huge s t o c k s o f t h e s p e c i e s which were a d v e r s e l y a f f e c t e d by t h e "El Niño" e v e n t s , p a r t i c u l a r l p t h o s e of 1972/73 and 1982/83 (1.787.000 Tons i n 1972/73 and 118.000 Tons i n 1982/53) which accoun t f o r t h e n e a r c o l l a p s e of f i s h e r i e s , p a r t i c u l a r l y dur ing 1982/83 when s a r d i n e t ook t h e p l a c e o£ anchoveta i n c a t c h f i g u r e s (1.172.030 Tons o u t of 1.404.000 Tons of p e l a g i c f i s h ) . During t h e occur rence of t he 1982/83 e v e n t a r a t h e r reduced anchoveta popula t ion u a s r epo r t ed . Tha t remained of t h e s p e c i e s sough t r e f u g e i n a r e a s w i th l i t t l e upsurg ing a c t i v i t y , go ing dovm as deep o s 100 m. The anchoveta popu la t i on was e r r a t i c and u n c e r t a i n due t o t h e s c a r c e 1952/63 spawning and t h e h igh m o r t a l i t y o f l a r v a e s i t u a t i o n which, t o a c e r t a i n degree , v a s e v i d e n t i n 1984 when t h e unloaded c a t c h anounted t o 23.000 Tons only.

S a r d i n e :

Eetween 1950 and 1972 unloading f i g u r e s o£ t h i s s p e c i e s were r a t h e r low. During y e a r 1964 t h e s a r d i n e c a t c h unloaded amounted t o approximate ly 10.000 Tons. From 1973 onwards t h e s i t u a t i o n undergoes a r a d i c a l change : t h e unloaded f i g u r e is now 132.000 Tons and it s t e a d i l y and r a p i d l y grows t o s u r p a s s t h e m i l l i o n t o n f i g u r e i n 1978 remaining on t h i s l e v e 1 up t o y e a r 1987. During 1983 t h e unloaded c a t c h arnounted t o 1.172.000 Tons l a r g e l y r e p l a c i n g t h e anchove ta i n t h e f i s h reduc ing i n d u s t r y . During t h e p e r i o d of unusua l oceanographic anomal ies - 1983 - s a r d i n e migra ted i n a nor th- sou th f a s h i o n u n t i l it reached t h e Peruvian s o u t h e r n c o a s t and t h e C h i l e a n n o r t h e r n c o a s t where i t came t o s e t t l e . The i n c i d e n c e of such a m i g r a t i o n on f i s h i n g a c t i v i t i e s was a d v e r s e s i n c e l a n d p roces s ing f a c t o r i e s l o c a t e d a long t h e l i t t o r a l came t o a s t a n d s t i l l .

The J u r e l and t h e Mackerel s p e c i e s wi ths tood t h e "El Niño'' e v e n t w i t h h igh b i o n a s s e s ; J u r e l c o n c e n t r a t e d i n t h e s o u t h w h i l s t Mackerel went no r th - wards. Adverce r e s u l t s r e l a t e d t o them were t h e outcome of t h e i r l a c k o f - v u l n e r a b i l i t y ( t h e y went deep down) t o t r a d i t i o n a l f i s h i n g b o a t s and gea r . It h a s been e s t i m a t e d t h a t around 40.000 people whose l i v e l i h o o d depends on t h e development o f f i s h i n g a c t i v i t i e s were a d v e r s e l y a f f e c t e d by t h e s i t u a t i o n .

Dernersal F i s h :

)!sin s p e c i e s i s Hake (Xer lucc ius g a y i pe ruanus ) ; t h e n co iaes 'Cabr i l l a ' ( P a r a l a b r a x ) ; 'Coco' (Pa ra lonchurus ) ; S o l e ( P a r a l i c h t h y s ) ; ' T o l l o s ' ( ~ I u s t e l u s ) 'Lorna' (Saaena d e l i c i o s a ) and ' F a l s o Volador ' ( P r i o n o t u s Stephano ph rys ) . The i r c a t c h i n c r e a s e d from 1973 onwards s u r p a s s i n g t h e 100.000 Ton f i g u r e . 1978 w a s a n o u t s t a n d i n g y e a r s i n c e more t han 300.000 Tons were unloaded. There is reason t o b e l i e v e t h a t t h e 1972173 "El Niño" even t s u b s t a n t i a l l y c o n t r i b u t e d t o t h i s f i g u r e . On t h e o t h e r hand, 1983 un load ings o£ t h e s e s p e c i e s o n l y accounted f o r 26.300 Tons of which 5.800 t o n s were r e p r e s e n t e d by Hake.

C o a s t a l F i s h :

A r t i s a n f i s h e r i e s l a r g e l y depend on t h e s e s p e c i e s which a r e a s s o c i a t e d t o mar ine l i t t o r a l a r e a s . The most i m ~ o r t a n t s~ec i e s are : 'Cabinsa ' ( I s a c i a c o n c e p t i o n i s ) , 'Co j i noba ' ( ~ e r i o l e l l a v i o l a c e a ) , ' L i s a '

1 (Mugil c e p h a l u s ) , Lorna ' (Saaena d e l i c i o s a ) 'Machete' (Ethmidium maculatum) ' P e j e r r e y ' (Odontes t h e s r e g i a ) and ' P i n t a d i l l a ' (Che i lodac ty lus ) .

Unloaded f i g u r e s remain s t a b l e , showing some improvement from 1970 onwards with app rox ima te ly 38.000 t o n s . The 'L i sa ' s p e c i e s c a t c h amounted t o 16.000 Tons. I n 1982 t h e t o t a l un loading amounted t o 70.000 Tons. T h i s group is c h a r a c t e r i z e d by t h e f a c t t h a t t r a d i t i o n a l s ~ e c i e s were r e ~ i a c e d by t h o s e t h r i v i n g i n t r o p i c a l waterc, p a r t i c u l a r l y orado' (coryphaenb) , ' ~ a r i i l e t e ' (Auxis) Sawf ish (Sconberomorus), 'Píanta' (blanta) S k a t e ( ) l y l i o b a t i s ) and Craw- f i s h (Penaeus) . The ' P e i e r i - -- , - _ , - - - - e y l s p e c i e s was p r a c t i c a l l y e x t i n g u i s h e d s e v e r e l y a f f e c t i n g a r t i s a n f i s h e r i e s .

2. Crustacean Fish :

During the last fifteen years the catch o£ these species has fluctuated between 1.000 and 2.000 Tons. 1983 witnessed an increase to more than 10.000 Tons by virtue o£ an unusual appearance of the 'titi' craw- fish species (Xiphopenaeus riveti)'which enlarged its living ground from the north down along the littoral to the Chilean border. The catch of this species amounted to 60%, or 6.000 Tons. As a result of high temperatures there was an unusual appearance of crab such as the species Euphylax robustus which caused damages to artisan fisheries.

This group is nade up by species such as '??achasf (E.lesodesma), Clams ( Semele, Gari) , 'Choros ' (Aulacomia) , 'Chanques ' (Concholepas) , etc., which underwent drastic mortality rates during 1983 even though the total catch figure did not show a significant variance as regards previous years. The species 'Concha de Abanico' (Argopecten purpuratus) reached outstanding levels due to successful spawning and recruitment. !ihilst yearly unloadings amounted to 1.000 Tons, the 1983 catch increased to 10.000 Tons.

The massive obiiteration of Macrocystis forests was recorded as well as a development favouring other algae such as green, brown and red algae. They show a leve1 of extraction o£ 100 - 300 TonslYear as from 1972.

Birds : 5 . - Guano birds are closely zssociated to the anchoveta and appear in

the chape of three species, pax~icularly 'Guanay' (Phalacrocorax b&nvUei), 'Piquero' (Sula varie~ata) and Pelican (Pelecanus occidentalis). Al1 three species sustained high mortality rates and, besides, the 1982/83 reproductive cycle was lost. The bird population was reduced to approximately 300.000 birds during 1983, which is the direct response to the unavailability of anchoveta as their food source. The decline in the bird population, on its turn, accounted for a decrease in the production of guano.

The species 'Chusco' (Otaria) and 'Fino' (Arctocephalus) sustained high mortality rates of their adult population due to lack of food. On their turn, sucklings also died as a result of their being neglected by theír parents. Regarding largest mammals, such as whales, the species Brydae was absent from its usual area of distribution in the north.

Chi l ean F i s h e r i e s :

P o s i t i v e anomal ies o£ t h e s e a s u r f a c e t e n p e r a t u r e occu r r ed du r ing t h e 1982/83 "El Niño" even t (2O-4.5'C) which ín t roduced s u b s t a n t i a l changes i n t h e supp ly , d i s t r i b u t i o n and mig ra t i on p a t t e r n s o f s o ~ e economical ly impor t an t s p e c i e s such as c r u s t a c e a n s , mol lusks and s h e l l f i s h . me s p e c i e s Anchoveta ( E n g r a u l i s r i g e n s ) was n o t caugh t and p r a c t i c a l l y vanished. Specimens s t u d i e d showed a l t e r e d p h g s i o l o g i c a l c o n d i t i o n s t r a n s l a t e d i n t o low f a t c o n t e n t . Ca tch f i g u r e s were reduced from 325.145 Ton i n 1981 t o 7.696 Ton i n 1983.

The Mackerel s p e c i e s (Scornber japonicus) widened i ts d i s t r i b u t i o n range m i g r a t i n g o f f i t s u s u a l c a p t u r e grounds; t h i s m i g r a t i o n \<as r e f l e c t e d i n a r e d u c t i o n of t h e s p e c i e s c a t c h which decreased from 97.457 Tons i n 1981 t o 9.280 Tons i n 1983. Concerning t h e J u r e l sp. (Trachurus murphy) t h e s t o c k s i z e was a p p a r e n t l y unchanged bu t a l t e r a t i o n s i n i t s v e r t i c a l and h o r i z o n t a l d i s t r i b u t i o n c o n t r i b u t e d t o . i t s a c c e s s a b i l i t y r e s u l t i n g i n a d rop i n c a t c h f i g u r e s . These were reduced from 1.060.909 Tons i n 1981 t o 865.272 Tons i n 1983.

'Chascon' p l a n t s (Lessonia n ig recens ) l i t e r a l l y vanlshed from t h e l i t t o r a l c o a s t a l zone i n t h e 1 Region. The s p e c i e s was o b l i t e r a t e d i n Antofagas ta , b l e j i l l o n e s P e n í n s u l a (23O15'S) by February , 1983. Unloading f i g u r e s du r ing

. 1953 amounting t o 50.838 Tons account f o r n e a r l y h a l f of t h o s e recorded d u r i n g 1982 and were s i m i l a r t o t h o s e o£ 1981. The 'Huiro ' s p e c i e s (Macro- c y s t i s i n t e r g r i f o l i a ) s u s t a i n e d an unusua l r e d u c t i o n d u r i n g 1982 t o t a l l y d i s a p p e a r i n g i n 1983. Its o b l i t e r a t i o n r e s u l t s i n a r e d u c t i o n o f o t h e r economica l ly i rnpor tan t i n v e r t e b r a t e such as t h e 'Cholga' (Aulacomga a t e r ) , 1 Lapaf ( F i s u r e l l a sp . ) , ' P iu re ' (Pyura c h i l e n s i s ) and 'Loco' (Concholepas concholepas) and E d i b l e Sea Urchin (Loxechinus a lbus) . Year ly un load ings d i d n o t d i f f e r rnuch i n 1982 and 1983 wi th t h e excep t ion of t h e e d i b l e s e a u rch in .

S p e c i e s which m i g r a t i o n s were b e n e f i c i a 1 t o f i s h e r i e s due t o t h e c l i m a t i c impact o£ t h e 19S2/83 "El Niño1' were : Spanish S a r d i n e (Sard inox sagax) , which miqra ted from Ecuador t o t h e n o r t h of Chi le . Other s p e c i e s which s u b s t a n t i a l l y i n c r e a s e d i n t h e c a t c h unloaded du r ing t h e e v e n t was t h e 'Boni to ' (Sarda c h i l e n s i s ) , Yearly un loadings of Spanish S a r d i n e which i n 1981 amounted t o 1.628.229 Tons, i n c r e a s e d t o 2.823.424 Tons i n 1983 w h i l s t t h o s e o£ 'Boni to ' whích in 1981 were of 2.727 Tons i nc reased t o 6.776 Tons i n 1983.

Concerning Colombia and i n t h e Tunaco Cove, c a t c h e s of \;bite Shrimp (Peanaeus o c c i d e n t a l e s ) went up w h i l s t t h o s e o f ' t iti ' shr imp (Aiphopenaeus r i v e r t i i ) dec reased , Catch ave rages pe r f i s h i n g v e s s e l f o r t h e P . o c c i d e n t a l i s s p , went down from 2.909 Pound/Tail i n 1982 t o 1.600 ~ o u n d 7 ~ a i l i n 1983 w h i l s t t h a t of 'titi' went down by 52% dur ing t h e same per iod . F i s h e r i e s o f sha l low water and ocean f i s h were reduced due t o t h e s o u t h v a r d s d i sp lace- rnent o f r e s o u r c e s . I n Ecuador, rnackerel (Scomber _japonicus) and o t h e r ~ e l a o i c s~ec i e s reduced t h e i r c a t c h from 1.800.000 Tons i n 1982 t o 443.000 *onswin 1683. S p a n i s h s a r d i n e (Snrdinoos s a g - ) v a s a b s e n t from t h e ca t ch .

T h i s s p e c i e s was t h e one most a f f e c t e d by t h e event . Other s p e c i e s of f i s h u s u a l l y t h r i v i n g i n t h e Guayaquil Gulf migrated towards t h e South i n t r o d u c i n g changes i n t h e i r d e n s i t y and a v a i l a b i l i t y . Other t r o p i c a l s p e c i e s were recorded f o r t h e f i r s t t ime , such as Yaenulum sexfaciatum. Reproduct ive c y c l e s of mar ine b i r d s l i v i n g i n t h e Galapagos I s l a n d s was none d u r i n g 1982 and h igh ly reduced du r ing 1983, showing popu la t i ona l dec reases of up t o 50% i n soae s p e c i e s of penguins and 'cormoranes' . High n o r t a l i t y rates were recorded f o r 'P iquero Azul' (Su la nebouxi), ' F r aga t a común' ( F r e g a t a minor) , ' F r aga t a Real ' (F rega t a magni f iens) and Erown P e l i c a n (Pe l ecanus o c c i d e n t a l e s ) . S c a l s (Zalophus c a l i f o r n i a n u s ) a l s o s u s t a i n e d h i g h m o r t a l i t y .

EIBLIOGRAPHY

A u s t r a l i a n Marine Sc i ences and Technology, Advisory Corrmittee, F i s h e r y Socio- economic Aspects of E l Kiño, G.L. Kesteven, 1983.

B o l e t i n e s ERFEN de l a CPPS (1950 - 1957).

CEPAL - O?íU. Los D e s a s t r e s l i a t u r a l e s de 1352-83 en B o l i v i a , Ecuador y Perú . E/CEPAL/G. 1274; 27 Diciembre 1983.

Coleg io de B ió logos Regiona l d e l Norte. 1 Congreso Xacional de B i o l o g í a Pesquera , J u n i o de 1934. T r u j i l l o , Perú , 1985. E d i t o r i a l L i b e r t a d Tru j i l l o .

Consejo Xaciona l de C i e n c i a y Tecno log ía , C ienc i a y Tecnología y Agresión Ambiental: E l Fenómeno E l Riño, Seminario en L ima , - Jun io de 1984. CO?!CYTEC. Lima, Pe rú , 1955.

ERFEK 1384. E s t u d i o Regional d e l Fznózeno "El Kiño" P a c í f i c o Sur Es t e . T a l l e r s o b r e e l Fenómeno "El Kiño" 19S2/83. Guayaquil , 12-16 Diciembre 1983. B o l e t í n h'o. 07, A b r i l 1984. NÚrero Espec i a l , Guayaqui l , Ecuador.

F l o r e s Palomino, Xonuel, I n c i d e n c i a Socio-Económica d e l Fenómeno "El Niño" 1982/83 en l a P e s q u e r í a Peruana. Conferenc ia Chapnan s o b r e e l Fenómeno E l Niño 1982/83. Guayaquil , Ecuador, Octubre 1986 (AGU-COI-0EE.I-CPPS) .

F l o r e s Palomino, Fíanuel, I n c i d e n c i a Socio-Económica d e l Fenóneno "El Niño" 1982/83 e n l a P e s q u e r í a d e l Langost ino y l a Concha de Abanico en e l L i t o r a l P e r ~ a n o . 1 Congreso Xacional de E i o l o g í a Pesquera. T r u j i l l o 1984.

IIlARPE-ICIARE.1 ( I n é d i t o ) T a l l e r T raba jo sobre '.!odelos para l a P r e d i c c i ó n d e l Rendimiento en e l S is tema de Af lorzc ieno Peruano. 1:XRPE - C a l l a o , 24 - 28 de Agosto de 1957.

IIURPE, Oficina de Estadística y Economía Pesquera. Pesquería F!aritima Peruana. Pesernbarque, Cacería y Censo de l a s Principales Especies y Grupos en e l Período 1950 a 1987.

I n s t i t u t o de l Mar del Perú. " E l Niño" y s u Impacto en l a Fauna Marina, EJoletín Volumen Extraordinario ISSN 4378 - 7699. Callao, Perú 1985 (Conferencias del Symposium).

I n s t i t u t o ?!acional d e Planificación 1983. Programa In tegra l de Rehabilitación y Reconstrucción de l a s Zonas Afectadas por l o s Desastres d e l a b!aturaleza. Volumen 1 ; Evalúación d e Dasos, J u l i o 1983.

CIIAPTER V


Little information is available on the socio-economic impact of changes in the sea level. Provided that the changes in the ternperature and the sea level appear gradually, the scverity of da~ages could be alleviated since there would be sufficient time to introduce changes in the current infrastructure in response to those changes. Such structural nodifications are embodied in the building up of physical works capable of adjusting to the new situation. On the other hand, if the rice in the temperature and the sea level appear suddenly and aperiodically, then the socio-economic impact vould be rather strong and notorious; they ~.!ould be even more acute due to the lack of an adequate infrastructure designed to endure such sudden alterations. This assurnption is valid insofar as short-term socio-econonic effects are concerned. Severe droughts and high rainfall indexes which resulted in overflowing of rivers, erosion of sloping zones, accumulation of sediments, etc. produced nanifold economic and social damages. During the occurrence of the event videspread floodings destroped the existing infrastructure therefore significantly reducing production indexes. Changes in the ocean regime had an adverse effect in the availability and catch of many species. Droughts impaired agricultura1 produce. Damages sustained by the sector included loss of crop, reduction of sediments, delay in sowings and, in some instances, soil salinization.

The cattle raising sector was also affected by death of cattle and dr.ying up of pastures. Physical infrastructure \gas also affected by damages to roads, bridges, railvays, airports. resulting in increases in operation costs and loss o£ perishable commodities. As far as the social sector is concerned, clinatic changes heavily da~aged the basic infrastructure impair- inp health and nutrition levels and increasing morbility. Sorne diseases, such as malaria, reached epidernic proportions. Large nurnbers of urban and rural dwellings were destroyed and/or daaaged. Total damages, according to ECLA (1983) calculations, amounted to USs3.480 million; US$2.000 million correspond to damages sustained by Peru; US$S40 million to Bolivia; US$640 million to Ecuador. 67% of the total figure, i.e., USS2.667 million, correspond to losses of the productive sectors; 182 (USS634 million) to damages to the physical infrastructure and the remaining 5% (USS179 million), to the social sector.

In Eolivia, 330.000 ~ r n ' were affected by droughts - approximately 35% of the countryts area - affecting 1.6 million people and causing the disappearance of some 4.000 head of cattle, 162.000 head of sheep and 68.000 head of camelides. Floodings covered an area of 150.000 Km' affecting some 700.000 people. tíalaria and other diseases became rampant in these areas. A total of 14.500 dwellings were obliterated or heavily damaged. The total anount of naterial darnages sustained by basic cervices and which rnay be

AREAS lNUNDADAS Y ZQNAS COCJ SEQUIA DURANTE EL FEI:O!,iG:O DE 'EL EJIRO' (982 iY83.

OCEANO PAC

ZONA DE CEQUIA

ZONA INUNDADA I

\ 1 MAPA No. 2.

a t t r i b u t e d t o t h e c l i m a t i c changes v a s c a l c u l a t e d a t USS22.5 m i l l i o n . C u l t i v a t e d l a n d was reduced by 172 wi th t o t a l l o s s of c r o p and a s i g n i f i c a n t f a 1 1 i n y i e l d s . :Iccording t o e s t i m a t e s . t h e t o t a l l o s s s u s t a i n e d by t h i s s e c t o r anounted t o US$241 mi l l i on . Because o£ f l o o d i n g s , 200.000 Ha. of a g r i c u l t u r a l l a n d \ a r e sub jec t ed t o e r o s i o n and were f l o o d e d by a l l u v i a l sed imcnts . L o s s e s i n t h i s s e c t o r have been e s t i n a t e d a t USS20 m i l l i o n . The t o t a l f i g u r e cor responding t o damages t o t h e a g r i c u l t u r a l s e c t o r and which can be d í r e c t l y a t t r i b u t e d t o c l i m a t l c changes h a s been c a l c u l a t e d a t US$447 m i l l i o n .

Tn Ecuador, t h e c o a s t a l Provinces o f Esmeraldas , Fíanabi, Guayas, E l Oro, v e r e s e v e r e l y a f f e c t e d by t o r r e n t i a l r a i n f a l l , f l o o d i n g s , ava l anches and s t r o n g dash ing o£ waves. The t o t a l s u r f a c e a f f e c t e d by t h e c l i m a t i c change r e p r e s e n t s 122 - 15% of t.he t o t a l s u r f a c e of t h e c o u n t r y and some 950.000 people s u f f e r e d heavy m a t e r i a l l o s s e s . Some 5.700 d w e l l i n g s i n t h e shanty- towns were t o t a l l y des t royed and 8.000 more were danages. A l 1 a r e a s under t h e i n f l u e n c e o£ f l o o d i n g s witnessed an i n c r e a s e i n m o r b i l i t y . lalater supp ly works i n twentg-nine towns ve re dacaged. Xine teen h o s p i t a l s and h e a l t h c e n t r e s were a l s o a f f e c t e d . T o t a l damages t o t h e e d u c a t i o n a l i n f r a s t r u c t u r e were c a l c u l a t e d a t US$6.6 mi l l i on . Loss of income from a g r i c u l t u r e , f i s h e r i e s and i n d u s t r y amounted t o USS22.7 rn i l l i on and t h e t o t a l c o s t o f ~ a t e r i a l damages t o t h e s o c i a l s e c t o r w a s of US$23.6 m i l l i o n .

I n Pe ru , a p r o t r a c t e d and ex t r ene drought s ea son a f f e c t e d o n e - f i f t h of t h e c o u n t r y ' s s u r f a c e (460.000 people). The c o a s t a l r e g i o n v a s s u b j e c t e d t o heavy r a i n f a l l and swells which r e s u l t e d i n f l o o d i n g s o f l a r g e p ropor t i ons . The i n s i g n i f i c a n t c a p a c i t y of n a t u r a l and nan-made d r a i n a g e works was u s e l e s s t o p reven t t h e occu r r ence of s eve re e r o s i o n i n t h e t o p sector o f t h e b a s i n w i t h t h e r e s u l t t h a t heavg f l ood ings and a l l u v i a l d e p o s i t i o n s a f f e c t e d come 830.000 people . S e c t o r s damaged by f l o o d i n g s s u s t a i n e d l o s s e s c a l c u l a t e d a t USS53.3 m i l l i o n as a r e s u l t of d-,.riages t o sewage systems. Forty-one water supp ly worl:s were des t royed; 875 s c h o o l s , 10.800 urban d w e l l i n g s were a l s o e f f e c t e d . Fanages t o s o c i a l c e r v i c e s were c a l c u l a t e d a t US$133 m i l l i o n . The l o s s o f i n c o n e by t h e a g r i c u l t u r a l s e c t o r anounted t o US$297 m i l l i o n ; US$241 m i l l i o n o£ which correspond t o d e c r e a s e s i n sowing and USS56 m i l l i o n t o i n d i r e c t l o s s e s . The i r r i g a t i o n i n f r a s t r u c t u r e w a s a f f e c t e d by s l u d g e i n t r u s i o n w i t h a l o s s of US$60 mi l l i on .

CHAPTER VI

IFPACT OF CLI!XTIC CHANGES IN TIIE CONTIIIEKTAL COASTAJ, ZONE

PEODUCTIVE SECTORS : AGRICüLTLRE, CATTLE, SILVICüLTURE, FORESTRY

Overall features of the area under discussion.are as follows :

Colombia

2 Area : 73.000 Km . ?lean Temperature : 26OC. High Rainfall Tndexes, showing a top mean of 8.000 vm. Important forest-related activities, comprising 704 of the country's total figure.

Ecuador

Its Pacific Coast conprises a 73.300 ~ r n ~ strip of land. Its climate is tropical, varying frorn warrn to rainy with tenperatures of 24OC and rain- fa11 indexes o£ 3.640 mm in Sucay and Esmeraldas to the dry and warrn climate found in the Santa Elena Peninsula, Guayas and El Oro, 'where rainfall indexes increase in a liest-East fashion, from 200 mrn to more than 3.000 mm.

Peru - The country's Pacific coast rneasures 140.000 1h2, 2.480 Ya in length

2nd 50 to 70 Ym wide. The region is comprised by ten Provinces : Tumbes, Piura, Lambeyeque, La Libertad, Kacash, Lima, Ica, Arequipa, i,loquegua and Tacna. The area is virtually devoid of rain with the exception o£ a-tiny strip in the northern section of the country vhere the climate is tropical and rainy. Generally speaking, the clirnate is desertic, showing sectors ~shere rainfall indexes are between 40 m.n and 100 mm.- ?!eañ :learlg tmpratures fluctuate between 18 and 22OC.

Chile

The coastal region is comprised by the western sections of t h e country's twelve regions with the exception of the Metropolitan Region. The Eorte Grande region shows a desertic climate, low rainfall and a nean tenperature o£ 16 - 19°C. In the Norte Chico the desert is the prevailing feature, with a dry climate, with a marginal desert between Copiapo (28m) and Valle- nar (64 mm); a barren plain, dry and luminous and a barren plain coastal climate with rainfall above 100 mm/year and mean ternperature of 15°C.

Central Chile offers a Mediterranean climate, with a yearly mean temperature of 14OC. Rainfall is heavier during winter months. Bio Eio and La Frontera show a dry ?íediterranean season which lasts less than six months. Rainfall surpasses 1.000 m reaching 1.600 mm at the utmost meridional point. In the Región de los Lagos there prevails a warm and rainy climate. Y!ean annual temperature o£ 12OC. Rainfall shows a range of 1.300 mm - 3.000 mm/ Aisean and Magellan offer severe climatic conditions with heavy rainfall fluctuating between 2.800 mm and 8.000 mm. Temperature is rather low producing huge ice fields.

1. Climatic Chanpes

Increases in rainfall indexes as a result of climatic changes would be responsible for the following situations :

- PIangrove forests in Colombia and Ecuador would not be subjected to significant changes given the clinatic conditions in which they usually grow.

- 9 TagualesV , 'pitales' and fine wood (head of the Atrato River) in

Colombia : It is lilcely that they rnay be affected since these species require drp weather.

- Jungles containing varied wood species in Colombia (San Juán River) : No changes have been foreseen in crops conditions.

- In the northwestern sector of the Basin of the Santiago and Atacames rivers in Ecuador, where there exist reserves of valued hard woods, it is expected that species would adapt to relative changes. No changes are foreseen in the piedmont strip o£ the Western i?anpe where important forestal resources are to be found.

- Rushes and species such as carob trees (Prosopis limensis),'Huarango' (Acacia huarango) in the coastal sector'nay benefit from soil fertility.

- Olive Groves (south and central coast) : No changes are foreseen in environmental conditions required by the crop.

- Regarding Chile's Central Region, no changes are foreseen regarding species such as Hawthorn (Acacia cavens) , 'Boldo' (Peumus boldus) , 'Quillay ' (Ouilla ja caponaria) , '?laitent ---(Fíaytenus -boaria) Oak (??oto£ aaus - oblicua). -

the same applies to the Poplar (Populus tremulus) existing in the IV Region. Forests of 'Pino Insigne' (Pinus radiata), 'Coigue' Oak (Notofagus dombeyi), 'Araucaria' (Araucaria araucana) in the Bio Bio and La Frontera Regions, as well as the Valdivian forest in the Los Lagos Region are not supposed to withstand any channes. In the Aisen and Elagellan Regions, 'Coigue' (Drymis witeri) - forests, 'Guaitecas ' Cypress (~il~erodendrium uviferürn) , 'Coiron' (Festuca ~racilaria) , 'LengaV (Hothof a ~ u s pumilius) and 'Kirre' (Kotofagus antarctica), and cold barren plains : NO changes are expected because of thermal and rainfall conditions in which the species grow.

.4s far as agricultura1 activities are concerned, climatic changes could give origin to the following conditions :

- Colombian Pacific Coasts - Crops of rice and coconut trees (High and Low Chocó) : Changes in crop conditions. Banana crops (Low Chocó) : These would be adversely affected.

- In Ecuador, Tabacco and Banana crops in the Esmeraldas Province would not be affected unless there occur overflowings caused by an increase in rainfall. The crops require dry weather conditions to ripen.

- I n t h e Aisen and Magellan Region changes i n wheat c r o p s cou ld be expec t ed ( X I Region). Also, c r o p s of a l f a l f a , v e g e t a b l e s , f r u i t ( n e c t a r i n e s , f i g s , wa lnu t s , almonds) would be a f f e c t e d . The s i t u a t i o n would remain s t a b l e conce rn ing c r o p s o f p o t a t o e s and o a t i n t h e i s l a n d and c o a s t a l t e r r i t o r i e s .

A s f a r a s c a t t l e r a i s i n i n g a c t i v i t i e s a r e concerned, t h e f o l l o w i n g cou ld be expec t ed :

- Colombia : E x i s t i n g numbers of head of c a t t l e would be d r a s t i c a l l y reduced s i n c e t h e e x c e s s of water would worsen s o i l c o n d i t i o n s r e s t r i c t i n g t h e a v a i l a b i l i t y ó f p a s t u r e s and r a i s i n g grounds.

- A s f a r a s Ecuador is concerned, no changes are f o r e s e e n a l o n g its c o a s t a l r e g i o n provided f l o o d i n g s a r e nonpresent .

- I n Pe ru , a n i n c r e a s e of r a i n f a l l over t h e c o u n t r y ' s d e s e r t i c areas would imply a b e n e f i c i a 1 e f f e c t s i n c e new g r a z i n g l a n d s cou ld be developed a l l owing f o r c a t t l e r a i s i n g .

- I n C h i l e , t h e Regions of Norte Chico (goa t s ) , C e n t r a l C h i l e (Sheep and g o a t s ) , Bio Bio and La F r o n t e r a ( d a i r y cat t le) , Los Lagos ( C a t t l e f a t t e n i n g and sheep) and Aisen - Magellan, where t h e c o u n t r y ' s l a r g e s t sheep f l o c k s are r a i s e d , would be g r e a t l y favoured by a n i n c r e a s e o f water s u p p l i e s .

2. Sea Leve1 Rice :

- The Colombian P a c i f i c Coast would w i t n e s s a development o f h a l o f i t e s p e c i e s a n a r e d u c t i o n of t h e a r e a i n h a b i t e d by t y p i c a l l y terrestr ial s p e c i e s found n e a r t h e c o a s t o r a l o n g r i v e r b a n k s -.,?lere t h e s a l t y wedge would have a p r o t r a c t e d e f f e c t . .No changes a r e fo:-eseen r ega rd ing 'Taguales ' and ' P i t a l e s ' .

- I n Ecuador, ha rd woods (Rasin of t h e San t i ago R ive r and sector o f Atacames); f o r e s t a l r e s o u r c e s (Piedmont s t r i p ) ; t abacco , banana and cat t le ( N o r t h e r l y s e c t o r , S a n t i a g o and Esmeraldas Ras ins ) ; banana (Guayas); c o f f e e , c o t t o n , peanu t and c a s t o r o i l p l a n t (>lanabi ta Savanca) ; bananas , cacao , suga rcane , rice and c a t t l e ( v a l l e g s washed by t h e Daule, Vinces and Eabahoyos R i v e r s ) and , g e n e r a l l y speak ing , a l1 r e s o u r c e s l o c a t e d f a r away from t h e i n f l u e n c e o f t h e c o a s t a l a r e a would n o t be a f f e c t e d by t h e e v e n t u a l i n t r u s i o n o£ a s a l t y wedge.

- Bear ing i n mind t h a t i n Peru most c rop a r e a s a r e f a r away from t h e c o a s t - i n t h e o a s i s - it is u n l i k e l y t h a t t h e s e s o i l s may be a f f e c t e d .

- I n C h i l e , changes would a f f e c t c r o p s of what, man-made p r a i r i e s n e a r t h e c o a s t ; f r u i t trees and s m a l l farm c r o p s i n Norte Chico, as w e l l as t h e A t r i p l e x cp. which, a f f e c t e d by t h e i n c r e a s e i n s a l i n i t g , would have a n a d v e r s e impact i n t h e development of sheep and goa t f l o c k s i n t h e C e n t r a l Coas t because of t h e r e d u c t i o n i n g r a z i n g grounds. Annual c r o p s and p r a i r i e s l o c a t e d i n t h e VI11 and I X Regions would be a f f e c t e d , t h u s , hav ing an a d v e r s e i n c i d e n c e on cattle. F o r e s t s e x i s t i n g i n the VI11 Region would be damaged.

- I n c a s e of f l o o d i n g s , t h e Fanana c r o p s growing i n t h e Guayas R ive r Bas in would be acverse l? a f f e c t e d . The Af r i can Palm Tree ( E l a e i s q u i n e e n s i s ) S o j a , Peanu t s , Fabaca , Rubber : Bear ing i n mind t h a t t h e s e a r e i r r i g a t e d s o i l s , no rneaningful changes a r e fo re seen . Regarding t h e E l Oro Province , its Banana c r o p s could a d a p t t o new c o n d i t i o n s . Coas t a l c r o p s of Cacao and Rice would be adapted t o c l i m a t i c changes. F i n a l l y , a g r i c u l t u r a 1 a c t i v i t i e s i n t h e Galapagos I s l a n d s would n o t be sub jec t ed t o meaningful changes.

- Regarding t h e Peruvian P a c i f i c Coas t sugarcane c r o p s (Northern O a s i s , P r o v i n c e s o f Lambeyaque, La L ibe r t ad , Ancash and Northern s e c t o r s of Lima), a n i n c r e a s e i n r a i n f a l l would add t o s o i l f e r t i l i t y t he reby i n t r o d u c i n g b e n e f i c i a l changes. For Cotton (Gossypium peruvianum), o r t h e c o t t o n v a r i e t i e s known a s ' t a n q u i s ' o r 'pima', changes i n r a i n f a l l i ndexes would b e n e f i t c rops . Rice growing areas, s u b j e c t t o i r r i g a t i o n , p o s i t i v e changes a r e f o r e s e e n as r e g a r d s y i e l d s and en largement of c u l t i v a t e d l a n d s ; t h e o p p o s i t e could apply t o t h e Vineyards of P i s c o provided i r r i g a t i o n is permanent; o the rwi se , i r r i g a t i o n p o s s i b i l i t i e s would have a b e n e f i c i a l i n f l u e n c e on t h e crop.

- Some changes are fo re seen i n t h e v a r i o u s Ghilean a d m i n i s t r a t i v e r e g i o n s : such i s t h e c a s e of t h e Norte Grande r e g i o n where v e g e t a b l e s , c o r n , p o t a t o e s and f r u i t o r c h a r d s would be g r e a t l y favoured by c l i m a t i c changes s i n c e t h e s e c r o p s could" e n l a r g e t h e i r domains. Crops such as C h i l i , Lima beans, watermelons and squash, co rn , p o t a t o e s and a l f a l f a , growing a t a n a l t i t u d e between 1.000 and 2.500 m., would n o t s u s t a i n meaningful changes.

- F r u i t t r e e s , Cherimoya, Lucurnas, l*!alnuts and h o r t i c u l t u r a 1 c r o p s growing i n t h e Korte Chico Region would improve c o n d i t i o n s by t h e d i r e c t i n f l u e n c e of tempera ture and t h e r e d u c t i o n of i r r i g a t i o n p r a c t i c e s . P o s i t i v e changes due t o a n i n c r e a s e i n envi ronmenta l humidity would a f f e c t c r o p s of tomatoes, . g a r l i c , l e t t u c e , c h i l i e s and onions ; a l s o , f r u i t trees such as peach, almond, n e c t a r i n e s , plums, avocados, o l i v e s , a p r i c o t s , p e a r s , lemon and oranges , c e r e a l s and v ineyards . The A t r i p l e x x. (Nor te Chico I V Region) would i n c r e a s e i ts a r e a of c u l t i v a t i o n .

- C e r e a l s and Legumes growing i n C h i l e C e n t r a l (Pe t roca - La Ligua) , would be p o s i t i v e l y a f f e c t e d by an i n c r e a s e i n water s u p p l i e s . Vegetab les f r u i t and t r a d i t i o n a l c r o p s (corn , wheat, beans) f r u i t . t r e e s ( a p p l e , t a b l e g rape , p e a r and peach) c u l t i v a t e d i n t h e V I Region as w e l l as rice, legumes and p o t a t o e s would no t s u s t a i n meaningful changes due t o a n i n c r e a s e i n r a i n f a l l . The same a p p l i e s t o i n d u s t r i a l Hemp c r o p s (San F e l i p e and Los Andes), Tobacco (Catemu, Va lpa ra í so ) , Sugar b e e t r o o t (Linares , Curico) .

- Small farm c r o p s c u l t i v a t e d i n Bio Bio and La F r o n t e r a (legumes, c e r e a l s , such as wheat, o a t and b a r l e y ) would n o t be a f f e c t e d . Higher humid i ty r a t e s would b e n e f i t g rapevines (Colemu, Yumbel, Qui l lbn and Nuble), and b e e t r o o t (Los Angeles and C h i l l a n ) . No changes are f o r e s e e n i n Los Lagos where c r o p s of p o t a t o e s , ' r a p s ' , o a t , b e e t r o o t , l u p i n e and l i n e n a r e t o b e found.

CHAPTER V I 1

INSTI'IZTTIONAL ASPECTS

The occurrence o£ climatic changes modify distribution patterns of temperature, rainfall and other meteorologlcal parametres which translate into effects which could either be beneficia1 to some areas or harrnful to others producing socio-economic impacts which bring us to think about the need to introduce social and institutional changes to strengthen their ability to adjust to them.

The recurring and aperiodical alterations of the ocean clinate have prompted the South East Pacific Region to initiate their co-ordinated study on the basis of a regional programe, as brought forward during the XII Ordinary -1eeting o£ the CPPS (1974). This programe has come to be known as ERFEN (Regional Study of the "El Riño" Phenoinenon - Estudio Regional del Fenómeno "El Eliño") . According to Jordán (1988) ERFEN is a co-operative$ and multidisciplinarp programe in which eighteen scientific institutions take part. The Programe counts on the support of the Intergovernmental Oceanographic Commission - IOC -, the 1:'orld Meteorological Organizacion - í;?O -, through the efforts o£ the Permanent South Pacific Com.nission - CPPS. Vithin the Commission's framework, an analysis is made of the progress of oceanographic, biological, fish related and neteorological regional research activities. A Joint IOC/ l:TIO/CPPS Group reports on those activities at the international level. The ERFEN Programe is linked to nany other global programmes on the ocean- atnosphere interaction, anongst which we would like to mention the Tropical Ocean and Global Atmosphere Programe, beinp implemented through TOGA-Pacific which is the organization concerned with "El Niñoff; also, the "El Niño" and the Southern Oscillation - EKSO - Programe which, besides IOC and VMO counts on the participation of other organizations such as the United States Wational Academy of Sciences. As far as the biological component is concerned, ERFEN is linked with the Ocean Sciences in Relation to Living Resources - OSLR - through the International Recruitment Programe - IREP. Other international programes related to ERFEK are : EPOCS, EBUC, ICOSS, et. al.

As an outcome of the Chapman Conference (International Synposium on the I I E ~ Ei'iTio~~ Phenomenon, Guayaquil (Ecuador) 27th - 31st October 1986), the need vas apparent in the cense that al1 inforrnation regarding ERFEN should be related to socio-economic aspects and that institutional arrangements should be included. To this effect, a project on the socio-economic impact of "El Ji'iño" is being developed by the Permanent South Pacific Commission. The project involves the Planning offices of the Region's countries besides al1 marine research organizations existing in the Region. An LWP-ERFEN project, recently negotiated by the CPPS - with the participation of IOC - incorporates a socio-econonic conponent.

A N N E X

THE 1982/83 "EL ~150" PHENO;.IEP!ON IN THE SOUTH EAST PACIFIC :

A CASE STUDY

The term "El i.!iñol' Phenomenon is a description o£ an oceanic-atmospheric large scale anomaly (Pacific Ocean) basically characterized by the aperiodical inflow of extremely warm waters (28'-30°C) into the South Fast Pacific Ocean,particularly off the Ecuadorian and Peruvian Coasts.

The appearance of unusually warm water produces dramatic alterations in the local meteorological, oceanic and biological regimes. Insofar as this Century is concerned, nedium and high intensity "El Niño" Phenomena have occurred in : 1902,' 1905, 1911, 1914, 1918, 1925, 1929, 1939, 1941, 1953, 1957/55, 1965, 1972/73, 1976, 1982/83 and 1987. The 1982/83 event has been the most intensively felt so far.

In wider oceanographic terms, the "El Niño1' Phenomenon could be defined as the expression, in oceanic scale, o£ the ocean-atmosphere interaction : It is the answer of the Equatorial Pacific Ocean to fluctuations o£ the atmospheric pressure systems and, therefore, of the ~iinds regime. The collapse of Equatorial trade winds and the sudden appearance of western winds in the Pacific central region produce Kelvin inner waves vhich travel along the Equator reaching the South American coast within a two-to-three month period. The Relvin waves have a dual effect : They intensify circul- ation trends eastwards and they deepen the thernocline (maximum vertical temperature gradient). 30th effects shov a tasciency to warm up the surface o£ the sea : The first, by conveping warrn water £roa the west and,the second, by preventing the surface upwelling - o£ deeper and colder waters (from below the thermocline) thereby producing coastal upwellings.

In 1983, the anomalous warming up recorded off the South American coast was related to two different water sources : Xorth of 15's the warm surface and low salinity water was associated with the tropical weter of the Panama Bight and South of 15's the warm surface and relatively higher salinity water was associated with an advection of subtropical water towards the coast (ERFER, 1984). As a result o£ this invasion of abnormally warm water, the sea surface temperature recorded great anonalies throughout the region. Thus, off the Peruvian coast warm anomalies o£ up to 10°C were recorded whilst off the Ecuadorian and Chilean coasts such anomalies reached up to 5°C (Logos, 1984; Cucalon, 1987). -

The a r r i v a l o f Ke lv in waves a t t h e E a s t e r n m o s t E q u a t o r i a l P a c i f i c Ocean and t h e s u b s e q u e n t d i s s e m i n a t i o n o f t h e s e waves t o w a r d s t h e p o l e a l o n g t h e American c o a s t was ev idenced by a s t r o n g d e e p e n i n g o f t h e s u b s u r f a c e t h e r m a l c t r u c t u r e t h r o u g h o u t t h e r e g i o n . Thus , and as a r e s u l t o f t h i s mot ion , o f f t h e E c u a d o r i a n c o a s t s and t h e n o r t h e r n P e r u v i a n c o a s t s , t h e t h e r m o c l i n e was f o u n d a t d e p t h s up t o f o u r times d e e p e r t h a n normal. E e s i d e s , a l 1 iso- t h e r m s , f rom t h e s u r f a c e up t o 12OC, were s i g n i f i c a n t l y d e p r e s s e d (more t h a n 100 m. i n some c a s e s ) . As a r e s u l t o£- t h i s , larae s u b s u r f a c e t h e r m a l a n o m a l i e s were r e c o r d e d , up t o g0C a t 50 m. d e p t h (?a20s, 1984; S i l v a y Ro.jas, 1984 ; Cuca lon , - 1986).

V a r i a t i o n s i n t h e s e a l e v e l a l s o r e f l e c t e d t h e v e r t i c a l movenents o f t h e t h e r m o c l i n e . An i n c r e a s e o f t h e sea l e v e l mus t be h y d r o s t a t i c a l l y o f f s e t by a s u r f a c e l a y e r o f warmer and t h i c k e r w a t e r . Thus , a r ise o f t h e sea l e v e l was o £ f s e t by a deepen ing o£ t h e t h e r m o c l i n e . I n 1953, o f f t h e E c u a d o r i a n and P e r u v i a n c o a s t s , t h e sea l e v e l r e a c h e d v a l u e s o f up t o 30 and 4 0 c n s . above normal , r e s p e c t i v e l y (La,=, 1984; Cucalon, - 1987). S e e F i g u r e Yo. 1.

Due t o t h e i n c r e a s e i n t h e s e a s u p e r f i c i a l t e m p e r a t u r e , t o t h e deepen ing of t h e t h e r m o c l i n e and , t o a l e s s e r e x t e n t , t o t h e rise o f t h e sea l e v e l , t h e h e a t c o n t e n t o f t h e ocean s u r f a c e l a y e r i n t h e E a s t E q u a t o r i a l P a c i f i c was s u b s t a n t i a l l y i n c r e a s e d . I n t h i s way, t h e f l o w o f h e a t f rom t h e ocean t o t h e a t c o s p h e r e was a l s o i n c r e a s e d p r o d u c i n g a n i n t e n s i f i c a t i o n o f convec t - i v e p r o c e s s e s i n t h e a t n o s p h e r e which a c c o u n t e d f o r u n u s u a l r a i n f a l l i n t h e S o u t h E a s t P a c i f i c r e g i o n .

Tne x h o l e S o u t h Aaerican l i t t o r a l vas s e r i o u s l y i n p a i r e d by heavy r a i n s a s s o c i a t e d w i t h a n abnorrsal d i s p l a c e n e n t s o u t ~ , * a r d s , beyond t h e E q u a t o r , of t h e I n t e r t r o p i c a l \:'inds Convergency Zone. T h i s Zone r c p r e s e n t s a f e a t u r e c o m o n t o a l 1 "El Xiño" e v e n t s . Along t h e Coloinbian P a c i f i c c o a s t r a i n f a l l d u r i n g 1983 was tt:tice t h e a v e r a g e f i g u r e ; i n Ecuador , r a i n f a l l was f o r t y times h i g h e r t h a n t h e n o r c a l l y h i g h a v e r a g e (Guayaqui l , J u n e 1983) ; and i n P e r u , it was u p t o 340 t i m e s t h e a v e r a g e f i g u r e , P a i t a , Elay 1983. ( J o r d a n , 1985; C u c a l o n , 1987).

On t h e i r p a r t , r i v e r s c o n s i d e r a b l y i n c r e a s e d t h e i r w a t e r volume r e s u l t i n g i n f r e q u e n t o v e r f l o w i n g which, t o g e t h e r w i t h l a n d s l i d e s o c c u r r i n g i n t h e I,ndean w e s t e r n s l o p e s w i d e l y c o n t r i b u t e d t o t h e en la rgement o f t h e o c e a n f l o o r i n t h e l o w e r s e c t o r s and t o t h e a l t e r a t i o n o f t h e c o i 1 and t h e eco- l o g i c a l s u b s t r a t u m . T o r r e n t i a l r a i n s and t h e s u b s e q u e n t o v e r f l o w i n g o f r i v e r s , f l o o d i n g s and wash ings had a h a r m f u l i n p a c t on o t h e r s e c t o r s , i n c l u d i n g : a g r i c u l t u r e , h o u s i n g , p u b l i c h e a l t h , e d u c a t i o n , t r a n s p o r t , i n d u s t r y , a r c h e o l o g i c a l r e m a i n s and , above a l l , t h e l o s s o£ hunan l i f e .

The i n c r e a s e o f t h e sea s u r f a c e t e a p e r a t u r e a n d , t h e r e f o r e , t h e i n c r e a s e o f t h e h e a t c o n t e n t o f t h e ocean s u r f a c e l a y e r i n t h e c e n t r a l and e a s t e r n P a c i f i c a l s o a c c o u n t e d f o r t h e u n u s u a l b u i l d i n g up o f h u r r i c a n e s i n p l a c e s l i k e T a h i t i and IIawaii. I n l i k e manner, b i g s t o r m s were produced n o r t h e a s t f rom t h e w e s t e r n :!orth American c o a s t (Lagos , 1984).

,{S a r e s u l t o f t h i s , l a r g e swells r e p c a t e d l y s t r o k e t h e S o u t h Aner ican c o a s t d r a s t i c a l l y i m p a i r i n g i t s morpf-iology. The j o i n t a c t i ~ n o f t h c s e a 1 l e v e l rise and t h e d a s h i n g o f l a r g e waves produced a landward r e t r c a t o f t h e c o a s t - l i n e , t h e f l o o d i n g o f l a r g e s e c t i o n s o£ t h e lowlands , t h e e r o s i o n o f i m e n s e c o a s t a l a r e a s , t h e w i p i n g o u t o f s h r i n p c u l t i v a t i o n ponds , t h e d e s t r u c t i o n o f mol luskan c o m u n i t i e s and c o a s t a l i n f r a s t r u c t u r e as w e l l as t h e d i s a p p e a r - a n c e of s o n e f i s h i n g c o m u n i t i e s .

C u r r e n t c i r c u l a t i o n , b o t h c o a s t a l and o c e a n i c , e v i d e n c e d s u b s t a n t i a l c h a n g e s a s well. A s s o c i a t e d 1 ~ 5 t h t h e a b r u p t v a r i a t i o n s i n t h e sea l e v e l and w i t h f r e q u e n t swells which r e p e a t e d l y strol:e t h e Sou th hmer ican c o a s t , c o a s t a l c u r r e n t s sholied a r a t h e r e r r a t i c behav iour b a s i c a l l y o v e r b o r n e by a n a r k e d s t r e n g t h e n i n g o f t h e v e r y s a n e c u r r e n t s . The f l o w of c o l d w a t e r s from t h e !Iunboldt C u r r e n t was c u b s t a n t i a l l y weakened and f o r c e d t o f a 1 1 back s o u t h - x a r d s , beyond u s u a l d i s t a n c e s f o r t h e p e r i o d o f t h e y c a r w h i l s t t h e mer id ion- a l f l o w o f w a r m t r o p i c a l water from t h e Panama 3 i g h t was s i g n i f i c a n t l y i n t e n s i f i e d r e a c h i n g l a t i t u d e s as sou thwards a s 15OS ( L a ~ o s , 1984) . T n s i d e t h e F , q u o t o r i a l c u r r c n t s systern, t h e Y o r t h e r n E q u a t o r i a l C o u n t e r c u r r c n t showed a n a r k e d i n t e n s i f i c a t i o n w I i i l s t t h e S o u t h e r n E q u a t o r i a l C u r r e n t e x p e r i e n c e d n o t o r i o u s r e v e r s i o n s ( F a n s e r , 1924).

To a g r e a t e x t e n t , t h e above c o n t r i b u t e d t o t h e a c c u n u l a t i o n o f w a r m water o f f t h e S o u t h A a e r i c a n c o a s t and t o t h e a p p e a r a n c e o f c e r t a i n f i s h s p e c i e s i n a r e a s n o r n a l l y devo id of then . Thus, o f f t h e P e r u v i a n c o a s t eand n o r t h of C h i l e t h e m a s s i v e appearance of t r o p i c a l s p e c i e s was r c p o r t e d ; i n l i k e c a n n e r , nany o c e a n i c s p e c i e s t:ere f o r c e d t o f a 1 1 back t o w a r d s t h e c o a c t . The c h a n g e s s u s t a i n e d by t h e n a r i n e env i ronment , p a r t i c u l a r l y t h e d e p r e s s i o n of t h e s u b s u r f a c e t h e r n a l s t r u c t u r e , gave r ise a l s o t o deep a l t e r a t i o n s i n t h e b e h a v i o u r a l and d i s t r i b u t i v e p a t t e r n s o f t h e r e g i o n ' s most i i n p o r t a n t p e l a g i c f i s h e r i e s . I n t h i s r e g a r d , n o t o r i o u s h o r i z o n t a l and v e r t i c a l m i g r a t i o n s o f t h e s e s p e c i e s were r e p o r t e d ( J i n e n e z and Herdson, 1954). As a r e s u l t , c a t c h f i g u r e s o f t h e s e s p e c i e s by f i s h i n g f l ee t s , p a r t i c u l a r l y f rom Ecuador t o P e r u , were d r a s t i c a l l y reduced t o t h e p o i n t o f f o r c i n g them t o s t o p o p e r a t i o n s . I n s h o r t , t h e l o s s e s s u s t a i n e d by t h e f i s h i n g s e c t o r i n Ecuador and P e r u s u r p a s s e d US$200 m i l l i o n ( J o r d a n , 198.5).

The economy o£ t h e r e g i o n ' s c o u n t r i e s i s Aeav i ly i n i l u e n c e d by t h e r e g i o n ' s f i s h e r i e s and a g r i c u l t u r e s o t h a t a d e e p e r knowíedge a b o u t t h e climatic, e c o l o g i c a l 2nd economic i n p l i c a t i o n s o f t h e "F1 Niñc" Pi1eno:-.cnon would p r o v i d e n e a n i n g f u l g u i d e l i n e s f o r sound nediuq- and long- term econo.?iic p l a n n i n g .

BIBLIOGRAPHY

CUCALON E. Variabilidad Oceanográfica Frente a la Costa del Ecuador Durante el Periodo 1981-1986. Bol. ERFEN No. 19, 11 - 26, 1986.

CUCALON E. Oceanographic Variability off Ecuador Associated with an El Xiño Event in 1982 - 1983. Journal of Geophysical Research, Vol. 92, 14.309 - 14.322. 1987. '

ERFEN, 1954. Condiciones Oceanográficas Durante El Ni,ño 1952-83. Bol. ERFEN No. 7, 4-8. 1984.

IIANSEN D. Aspectos a Gran Escala de Condiciones Atmosféricas y Oceano- gráficas Asociadas con El Riño de 1982-83. Rev. Com. Perm. Pacífico Sur, 15, 49 - 66. 1984.

JIXENEZ R. Y D. HERSOK. Efectos. de El Niño 1982-83 sobre los Recursos Pesqueros en Ecuaodr. Rev. Com. Perm. Pacífico Sur, 15, 269 - 292. 1984.

JORDU R. Ecological Changes and Economic Consequences.of ELNiño Phenomenon in the Southeastern Pacific. Bol, ERFEN, No, 12, 27 - 33. 1985.

LAGOS P. E l Ciño '1982-83 y las ~lteraciones-Climdticas- en el Peru; Rev. Corn, Perm. Pacífico Sur, 15, 95 - 120. 1984.

SILVA N. y R. ROJAS. Presencia del Fenómeno El Niño 1982- 1983 Frente a la Costa Norte de Chile. Rev. Corn. Perm. Pacífico Sur, 15, 121- 140. 1984.

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