Spatial and Multi-temporal Analysis of Deforestation andQuantification of the Remnant Forests on Porto Rico Island,Paran, Brazil

Joo Batista CamposInstituto Ambiental do Paran - IAP. Av. Bento Munhoz da Rocha Neto, 16. - CEP 87.030-010 Maring - Paran -Brazil

ABSTRACT

The process of land occupation by the state of Paran practically decimated its forests. Presently, only 7% from atotal area of 83.41% is covered by forests. Most of them are now concentrated in the "Serra do Mar" and in theIguau National Park. With regard to forest cover the most critical region is situated in the northwestern of the statewith less than 1% of its area covered by forest. This restricted area mainly consists of conservation units and theislands of the high Paran River floodplain. The present study consists of a spatial and multi-temporal analysis ofdeforestation and the quantification of the remnant forests on Porto Rico island (22o45S; 53o15W), which havetheir occupation history linked to the colonization process of the region. Historical aerial photographs of thisregion were used and the relationship of deforestation with the process of colonization and social transformation ofthe region is discussed.

Key words: photogrammetry, alluvial forest, floodplain, forest.

INTRODUCTION

Originally, the state of Paran had 83.41% of itsarea covered with forests (Maack, 1968). Theprocess of territorial occupation of the statebegan from the Atlantic coast, reached the firstplateau of Curitiba and rapidly developed on thesecond and third plateaux towards the Paranriver. The process practically decimated wholeforests; currentlly only about 7% of the originalforest cover remains (Fundao SOS MataAtlntica 1992/93).

In the area of convergence of the high Paranriver floodplain, between the states of Paranand Mato Grosso do Sul, the situation is morecritical. Forests have been almost totallydestroyed. The original forest covering thenorthwestern area of the state of Paran doesn'tsurpass 1%; in Mato Grosso do Suldeforestation already reached critical levels withonly 42.2% of native vegetation in the wholestate and 0.83% in the southern area (Fundao

SOS Mata Atlntica 1992/93; Fundao Ipardes,1992).

The fluvial archipelago of the Paran riverbetween the states of Paran and Mato Grossodo Sul is formed by a wide alluvial channel withlow declivity (7cm/km) (Souza-Filho &Stevaux, 1997), braided channels, hundreds ofsmall lakes and more than 300 islands(Agostinho & Zalewski, 1996) whose history istied up with the territorial occupation of thestate of Paran .

Deforestation of the islands is related to thechanges and social transformations that occurredin the area. The colonization process and use ofthe soil have dictated the rhythm and extensionof the deforested areas. The process ofdeforestation is spatial and temporally evaluatedfrom available historical aerial photographs ofthe area; the remaining forests on Porto Ricoisland are quantified and their relationships withthe occupation process and land use in the areais discussed.

MATERIALS AND METHODS

Study areaThe area under analysis is one of the severalislands that compose the fluvial archipelago ofthe High Paran river. According to the mostrecent official map of the area (1980), the islandhad an area of 107.55 ha, lying approximately at

22o45'S and 53o15'W. The climate of the areaaccording to the Keppen system is Cfa -tropical-subtropical climate with hot summer(annual average of 22oC) and annual mediumprecipitation of 1.500 mm (Campos & Costa-Filho, 1994). Altitude of the area is close to 230m above sea level (Fig. 1).

53 30o 53 15o

CITY

CITY

PARAN

MATO GROSSO DO SUL

23 00o

22 45o 22 45o

PARAN STATE

STATE

STATE

DIRECTION OF FLUX

ADVANCED LAB OF NUPELIA

Region of study

BRAZIL

PORTO RICO

PORTO RICO

Baia

Rive

r

Paran

Rive

r

Paran

Rive

rPa

ran

River

Ivin

hem

a

Rive

r

Ivin

hem

a Riv

er

Mutum

Isla

nd

Mutum

Islan

d

Porto R

icoIsla

nd

N

1 km

Fig. 1. Site of the area under analysis

The area is situated in the SemideciduousSeasonal Forest phytoecological region and thelocal vegetation is classified as SemideciduousSeasonal Alluvial Forest (IBGE, 1992; Campos& Souza, 1997).

MethodologyVertical metric aerial photographs obtained inthe years 1952 (scale 1:25.000), 1965(1:40.000), 1970 (1:50.000), 1980 (1:25.000)and 1996 (1:50.000) were used for multi-temporal evaluation of deforestation and for thespatial quantification of the vegetation. Aerialphotographs were analyzed and interpretedvisually, with the aid of a stereoscope, and geo-referenced to a cartographic basis (Loanda

sheet, SF.22-Y-A-V DSG/IBGE, scale1:100.000).

The mapping of the identified vegetation typeswas elaborated by means of overlays oftransparent sheets, fed into the SGI/INPE

program, with calculations of areas andperimeter limitations on the photos alreadydigitally formated. The COREL-DRAW version7.0 was used for final edition of the photo-mapsand legends were placed according to thepatterns related to the vegetation types identifiedin the aerial photographs.

Concerning the history of occupation and humandominion of the area under analysis, old maps,

research projects reports and interviews withtechnicians responsible for the areas surveyswere consulted.

RESULTS AND DISCUSSION

History of occupationThe occupation process of the territory ofParan is a relatively recent occurrence. Untilthe beginning of this century, economic activity

occurred in less than a third of the area of thestate and was restricted and concentrated on thecoast and in the south. Products that formed thebasis of the states economy, such as gold in the17th century and the extraction, industrializationand export of the mat tea and wood in the 19thand early 20th centuries, were exploited. Asfrom 1930, an accelerated phase of thedestruction of Paran forests took place(Codesul, 1989) (Table 1).

Table 1. Historical process of deforestation and percentages of forest covering the state of Paran (1890 - 1990).Year Original forest

(km2)Deforested area (km2) Annual index of

deforestation (km2)Covering Forest

(%)1890 167,824 - - 83.411

1930 129,024 38,800 970 64.121

1937 118,022 49,801 1,571 58.651

1950 79,834 87,990 2,938 39.671

1965 48,136 119,688 2,113 23.921

1980 23,943 143,881 1,613 11.902

1985 16,468 151,356 1,495 8.393

1990 15,030 152,794 287 7.5931 Maack (1968)2 Inventrio de Florestas Nativas (IBDF) (Gubert-Filho, 1993)3 Fundao SOS Mata Atlntica (1992/93)

The original forests formerly covering 83.41%of the 201,203 km2 of the total area of Paran(Maack, 1968) suffered a fast degradation. Sincedeforestation rhythm is linked to thecolonization process and the expansion of theagricultural area, the highest peak observed inthe annual index of deforestation occurredbetween 1937 and 1950 (2,938km2). This factcoincided with the beginning of colonization ofthe northern part of Paran, specifically in thearea around the city of Londrina, founded in1937, from which several districts and townswere dismembered, such as Apucarana (1943),Rolndia (1943), Arapongas (1947) andMandaguari (1947).

The second largest annual index of deforestation(2,113 km2) occurred between 1950 and 1965,and it was related to the process of colonizationof the northwestern areas, or rather, with thefoundation of the cities of Maring (it became adistrict in 1951), Paranava (1951), Umuarama(1960); also in the southwestern region of

Paran, where the cities of Cascavel (1951),Francisco Beltro (1951), Pato Branco (1951)and Toledo (1951) were founded.

Between 1965 and 1985, deforestation indexesdecreased from 1,613 km2/year-1 to 1,495km2/year-1, although indexes remained relativelyhigh. This was the era of the expansion of theagricultural frontier in the southwestern andnorthwestern regions of the state towards theParan river.

Between 1985 and 1990 when the agriculturalfrontier didnt exist any more and forestdestruction was completed, this index decreasedto 287 km2/year-1. In 1990 index of forestcovering reached 7.59% of the state. Remainingforests were concentrated in conservation units,mainly on the coast in the Serra do Mar and inNational Park of Iguau (Campos, in press). Thenorthwestern area analyzed in this study has lessthan 1% of its area covered with forests(Fundao Ipardes, 1992).

Initially, the colonization of the northwesternarea was the initiative of the states governmentwhen it founded the colony of Paranava in1939. The town was elevated to district category

in 1951; several districts were later ondismembered from the original town(Outline 1).

Outline 1. Origin of the district of Porto Rico, Paran, Brazil, and year of foundation of the original districts(Source: SEMA 1997)

Paranagu (1648)_____________________________________________________________________ Coast L Curitiba (1693) L Castro (1789) _______________________________________________________________ 1o Plateau L Tibagi (1872) L S. Jernimo da Serra (1920)__________________________________________ 2 o Plateau L Jata (1932) L Londrina (1934) L Apucarana (1943) L Mandaguari (1947) L Paranava (1951) L Porto Rico (1963)_____________ 3 o Plateau

Regional context of Porto Rico islandThe district of Porto Rico is situated on the bankof the Paran river and has several islandswhose occupation history is linked to that of thetown of the same name.

The island under analysis is called Porto Ricoisland and is situated in front of the town ofPorto Rico. By the 1983 agreement, INCRA(National Institute for Colonization andAgrarian Reform), the organization responsiblefor land regulatation in Brazil, transferredauthority for the survey of land regulation on theislands of the Paran river to the Institute ofLand, Cartography and Forest (ITCF, currentlyEnvironmental Institute of Paran, IAP).Because of boundary indefinition between thestates of Paran and Mato Grosso do Sul,technicians of ITCF established the deepestsounding of the river bed and thus, a criterionfor the boundary between the two states.

According to Feuerschuette (1985), there was ajuridical controversy regarding the islands of theParan river, or rather, the jurisdiction oflimiting states over the islands. The authoremphasized that the political and administrativejurisdiction exercised by the state of Paran orby the frontier districts has been defined andconsolidated throughout the years. Moreover,with regard to interstate boundaries, it wasemphasized that river soundings criteria,

establishing the bordering line of the stateterritories, would with great difficulty prevail onthat of the political and administrativejurisdiction exercised by the Paran state. Thiswas especially true because of the great mobilityof the channel as a result of the flood cycle andsand accumulation, both factors favouringconstant changes. In a study on sedimentologyin the high Paran river floodplain, Stevaux(1994), contemplating a specific section in thearea of Porto Rico, confirmed intense migrationand changes in the soundings of the Paranriver.

Taking into consideration the fact that thehistory of occupation of the islands of theParan river, especially of the island underanalysis, is linked to the state of Paran, thediscussion on the deforestation process and itsconnection to the Paran State are rightlyjustified.

Land occupation on Porto Rico islandThe first information regarding the occupationon the island, consisting of five houses(1964/66) was registered on the map of Loanda(SF.22-Y-A-V DSG/IBGE). According toSUCAM (now National Health Foundation -FNS), ten houses and a population of 23residents existed in the island in 1983. In 1987the same registers reported that two houses and

3 residents existed on the island. Same numberswere registered for 1993 (FUEM/CIAMB-PADCT, 1993). Now, the island is occupied bytwo presumed owners, extensive cattleraising, a single house occupied eventually byone of the proprietors who actually lives in thetown of Porto Rico.

According to FUEM/CIAMB-PADCT (1993),the islands of the Paran river became heavilyoccupied in the 70s when transformations inagriculture and cattle raising expansion expelledthe small proprietors, partners, lessees andleaseholders of the rural areas of the districts inthe neighbourhood of the Paran river. On theother hand, changes in agricultural production,the "modernization" of agriculture, thesubstitution of the coffee plantations by cattleraising (the latter demanding heavy expansion ofarea) and the flood of 1982/83 provoked theexpulsion and displacement of the populationliving on the islands of the Paran river duringthe 80s and, probably, land concentration.

In spite of the occupant decrease between 1987and 1997, the degradation process anddeforestation of the island didn't diminish, asmay be seen below.

Total area of Porto Rico island Siltdeposition and erosionThe total area of the island related to dynamicsof silt deposition and erosion by the Paran riverunderwent several dimensional variations. In1952, the reference year for the original forestcovering in this study, the island had 101.31 ha.A coalescent sandbank in formation and theinitial stage of colonization may be identifiedfrom the aerial photographs. The sandbankdeveloped and fused itself to the island. In the1965 aerial photograph, an increase of 12.4 hato the total area might be noted, establishing theislands area at 113.71 ha.

The coalescent or fusing sandbank had alreadybeen identified by Santos et al. (1992).According to these authors, these sandbanks arediagonal appendixes to the islands and fused tothe latter upstream. Such a fusion and theformation of a channel between the fusedsandbank and the original bank of the islandmay be observed in the aerial photography of1965.

From 1965, an erosion process began on theisland with loss of area, reaching to the currentlevel of 103.12 ha (Table 2).

Table 2. Total area, historical process of deforestation and percentage of forest covering for Porto Rico island (1952- 1996).

Year Total area(ha)

Remainingforest (ha)

Deforestedarea (ha)

Annual deforestation(ha)

Forest covering(%)

1952 101.31 93.92 - - 92.081965 113.71 47.91 65.80 5.06 42.131970 111.87 26.78 85.09 3.86 23.941980 107.55 18.28 89.27 0.42 17.001996 103.12 6.17 96.95 0.48 5.89

The speed of area loss may be associated withthe occupation and deforestation process of theisland. The interlacement of roots at severaldepths by forest vegetation in its several strata(arboreous, shrub and herbaceous) favoured theagglutination and cohesion of soil particles,increasing resistance to disaggregation with aconsequent decrease of the erosive process. Onthe other hand, extensive cattle raising on theisland caused the disembankment of the margins(when cattle went to the river to drink the water)and contributed to the erosion process. Perhapspopular culture picked up in one of the manymeetings with the local population fits in very

well: Elsewhere, the riparian vegetationprotects the water of the river from the soil thaterosion carries away. It is different in the Paranriver. Riparian vegetation protects the soil of theislands from the waters of the river. This is aclear allusion to the protection that the riparianforest gives to the islands against the erosiveeffect of the river.

Deforestation in Porto Rico islandThe historical process of deforestation in PortoRico island may be visually observed in the

photo-maps elaborated from aerial photographs(Fig. 2).

Fig. 2. Evolution of deforestation in the Porto Rico island for the years 1952, 1965, 1970, 1980 and 1996.

1980

22 45 S

53 15 W

Legend 1980 haForest

%18,28 17,00

Deforested area 89,27 83,00Total107,55 100,00

22 45 S

1965

53 15 W

Legend 1965 haForest

%47,91 42,13

Deforested area 65,80 57,87Total113,71 100,00

1970

22 45 S

53 15 W

Legend 1970 ha26,78

%23,94

Deforested area 85,09 76,06Total111,87 100,00

53 15 W

1952

Legend 1952 haForest

%93,29 92,08

Sanbank in colonization 2,21 2,18Area in colonization 5,81 5,74

Total101,31 100,00

Paran

Rive

r

150 150 300 450 600 m

Scale

0

1996

22 45 S

53 15 W

From the photo-maps, it could be observed thatPorto Rico island had all its original vegetationseemingly intact in 1952 when 92.08% of itstotal area was covered by forest and theremaining percentage was distributed betweenvegetation areas (5.74%) and in sandbanks withincipient colonization (2.18%).

Between 1952 and 1965, more than half of theisland was already deforested (57.87%).Between 1965 and 1970, deforestation processpractically maintained the same rhythm (Fig. 3).

a) b)

1952 1965 1970 1980 1996

Anos

0

20

40

60

80

100

120

Area (ha)

Total area Remaining forest Deforested areadesflorestada

1952 1965 1970 1980 1990 1996Anos

0

20

40

60

80

100

%

Porto Rico island Paran State

Fig. 3. a) Total area, deforested area and remaining forests in the Porto Rico island between 1952 and 1996 and b)percentage of remaining forests of the Porto Rico island and Paran State (1952 - 1996).

Deforestation rhythm coincided with thecolonization process and social transformationsin the area. Rosa (1997) stated that between1962 and 1967, due to the overproduction ofcoffee in Brazil and in order to maintain theproducts international prices, the coffee shruberadication policy was employed. Two hundredand five million coffee shrubs were uprooted. Inthe northwestern area of Paran, sixty twomillion coffee shrubs were eliminated andpasture was introduced in the area. Since coffeeplantation undoubtedly absorbed a great deal oflabour, the eradication of the coffee shrubsexpelled part of the population in the area as aconsequence (Rosa, 1997 p.381). The islands ofthe Paran river, considered as periphericalareas to agricultural exploration, served at thattime as absorption areas for the populationexpelled from the rural production environment(FUEM/CIAMB-PADCT, 1993). This fact mayexplains the deforestation speed until 1970.

Between 1970 and 1996, the deforestationrhythm greatly decreased. This fact should beattributed to the exhaustion process of theremaining forest, which only occupied 25% of

the area of the island in 1970. Between 1970and 1996, 18.1 ha were deforested and atpresent only 3 florest fragments remain on theisland, totalling 6.17 ha, which represented5.98% of its area.

In terms of annual rhythm of deforestation, highvalues have been observed in the beginning ofthe occupation (up to 1970), with a decrease insubsequent years (Table 2 and Fig. 3a). In spiteof a decrease in the number of occupants of theisland between 1980 and 1996, deforestationmaintained the same rhythm as that of the periodcomprising 1970 to 1980. This was probablydue to the expansion of deforested areas usedfor cattle raising.

Percentage of the remaining forests on PortoRico island as compared to those in the state ofParan, quickly decreased until the 70s. Later, itmaintained a similar rhythm to that of the state,albeit at a slightly higher level. Projectionsindicated a steadily decreasing process of forestcovering both in Paran and on the island(Fig. 3b).

CONCLUSIONS

Due to the physical smallness of the area,necessarily needing cartographic bases at largescales, aerial photographs have been a valuableinstrument in the reconstruction of the historyand true situation of the areas deforestation.Due to the available multi-temporal series andtheir high resolution level, aerial photographsare especially indicated for identification,quantification, spatial location andestablishment of plans and directives for areareforestion and forest recovery in small andlarge enterprises. This study has been useful inanalysing the historical evolution of the islandsocuppation: although it really began in 1952,deforestation on Porto Rico island quicklyreached the levels of the state and followedclosely the Paran level of forest destruction.

The occupation process and deforestation ofPorto Rico island seem to be related not only tothe colonization process but also to the socialchanges occurring in the area, mainly thesubstitution of cultures that use a great amountof labour (for instance, coffee plantations) byactivities that need area expansion forproduction with few employees (for instance,cattle raising). Consequently, land concentrationand utilization excesses in the occupation of theagricultral frontier are brought about.

Considering that, according to the law, allproperties should have at least 20% of their totalarea as forest reserve, besides those constitutingpermanent preservation, and since on Porto Ricoisland only 5.89% of its area is covered withforests, it could be concluded that Porto Ricoisland is being used illegally. Consequently,urgent action is needed towards the recovery ofits destroyed forests.

ACKNOWLEDGEMENTS

Achnowledgements are due to SENAGRO -Sensoriamento Remoto S.A., especially toFrancisco Lothar Paulo Lange Jr. and CarmenTruite, for the collaboration in the making of thephoto-maps and to Prof. Maria Cristina Rosa forthe suggestions presented in the discussion of

the paper. To Curse of Post-graduation inEcologia de Ambientes Aquticos Continentais- Universidade Estadual de Maring and CNPq.

RESUMO

O processo de ocupao das terras do Paranpraticamente dizimou as florestas do Estado,que originalmente possua 83,41% de sua reatotal coberta com florestas. Atualmenteremanescem aproximadamente 7% da rea comflorestas, concentradas na Serra do Mar e noParque Nacional do Iguau. Na regio noroeste,a situao mais crtica, com menos de 1% desua rea coberta por florestas, concentradas,principalmente, em unidades de conservao enas ilhas da plancie de inundao do alto rioParan. Esta plancie formada por uma amplacalha aluvial, com inmeros canais, lagoas eilhas, que tm sua histria de ocupao ligadasao processo de colonizao na regio. Nestetrabalho, realizada uma anlise espacial emulti-temporal dos desflorestamentos e umaquantificao das florestas remanescentes dailha Porto Rico (22o45S; 53o15W), por meiode fotografias areas histricas da regio ediscutidas as relaes destes desflorestamentoscom os processo de colonizao etransformaes sociais ocorridas na regio.

REFERENCES

Agostinho, A.A.; Zalewski, M. (1996), Aplancie alagvel do alto rio Paran:importncia e preservao, Maring - PR :EDUEM. 100p.

Campos, J.B. (in press), Unidades deConservao no Estado do Paran: aes econtradies. Revista do Instituto Florestal -Srie Registros.

Campos, J.B.; Costa-Filho, L.V. (1994),Proposta tcnica de implantao da rea deproteo ambiental do Arquiplago de ilhaGrande. Curitiba-PR : SEMA/IAP. 54p.

Campos, J.B.; Souza, M.C. (1997), Vegetao.In: A Plancie de Inundao do Alto RioParan: aspectos fsicos, biolgicos esocioeconmicos, ed. Vazzoler, A.E.A.M.;

Agostinho, A.A.; Hahn, N.S. Maring :EDUEM : Nuplia, 1997. pp. 331-342.

Codesul - Conselho de Desenvolvimento doExtremo Sul. (1989), Diretrizes para apreservao e conservao da natureza epara o desenvolvimento florestal na regiosul do Brasil. Curitiba - PR, 60p.

Feuerschuette, R.C. (1985), Parecer no.146/84/PROJU - ITC. Revista de DireitoAgrrio e Meio Ambiente, 1, 150-152.

FUEM/PADCT-CIAMB. (1993), Estudosambientais da plancie de inundao do rioParan, no trecho compreendido entre a fozdo rio Paranapanema e o reservatrio deItaipu. Maring: Fundao UniversidadeEstadual de Maring. 3v. (Relatrio depesquisa - Apoio PADCT-CIAMB).

Fundao Ipardes. (1992), Diagnstico para aimplantao de polticas para o setorflorestal no Paran. Curitiba - PR :Fundao Ipardes. 48p.

Fundao SOS Mata Atlntica/INPE. (1992/93),Atlas da evoluo dos remanescentesflorestais e ecossistemas associados dodomnio da Mata Atlntica no perodo de1985 - 1990. So Paulo : INPE. 20p.

Gubert-Filho, F.A. (1993), O desflorestamentodo Estado do Paran em um sculo. Paperpresented at Conferncia del Mercosur sobreMedio Ambiente e AspectosTransfronteirizos, 61-69. Posadas, Argentina.

IBGE - Fundao Instituto Brasileiro deGeografia e Estatstica. (1992), Manualtcnico da vegetao brasileira. Rio deJaneiro : IBGE. 92p. (Srie ManuaisTcnicos em Geocincias; 1).

Maack, R. (1968), Geografia Fsica do Estadodo Paran. Rio de Janeiro : J. Olympio.442p.

Rosa, M.C. (1997), Processo de ocupao esituao atual. In: A Plancie de Inundaodo Alto Rio Paran: aspectos fsicos,biolgicos e socioeconmicos, ed. Vazzoler,A.E.A.M.; Agostinho, A.A.; Hahn, N.S.Maring : EDUEM : Nuplia, 1997. pp.371-394.

Santos, M.L.; Fenandez, O.V.Q.; Stevaux, J.C.(1992), Aspectos morfomtricos das barrasde canal do rio Paran. Boletim deGeografia, UEM-DGE, 10, 1, 11-24.

SEMA - Secretaria de Estado do MeioAmbiente e Recursos Hdricos do Paran.(1997), Arquivo Grfico Municipal doEstado do Paran. Curitiba. 53p.

Souza-Filho, E.E.; Stevaux, J.C. (1997),Geologia e geomorfologia do complexo rioBaa, Curutuba, Ivinheima. In: A Plancie deInundao do Alto Rio Paran: aspectosfsicos, biolgicos e socioeconmicos, ed.Vazzoler, A.E.A.M.; Agostinho, A.A.; Hahn,N.S. Maring : EDUEM : Nuplia, 1997.pp. 3-46.

Stevaux, J.C. (1994). Geomorfologia,sedimentologia e paleoclimatologia do altocurso do rio Paran (Porto Rico, Pr.). BoletimParanaense de Geocincias, 42, 97-112.

Received: June 20, 1998;Revised: June 30, 1998;

Accepted: September 14, 1998.