marine component of icmicm.landcareresearch.co.nz/knowledgebase/publications/...ap1 ap2 ap3 ap4 ap5...

IntroductionPaul Gillespie ‐ Cawthron

Goal of the marine component:

To develop a “river plume ecosystem” (RPE) basis for evaluating and managing catchment‐sea linkages

In order to:Facilitate coastal stakeholder input to catchment management as a

step towards Integrated Coastal Management

Are river plumes important?

Major areas of investigation

• Nelson Bays Hydrodynamic Model ‐ plume dynamics

• Synoptic surveys of temperature, salinity, nutrients, chl a, suspended sediments, contaminants.

• Mass transport of nutrients (N, P, Si) from the catchment into Tasman Bay.

• Mapping of intertidal and subtidal habitats created and nourished by the river outflow.

• Spatial patterns of seabed characteristics generated by the river plume .

• Suspended sediments in near‐bottom waters.

Water column: variable in size & shape and moves around

1500 km2

Chl a

How big is the plume?

173.0 173.1 173.2

41.1

41.0

40.9

40.9

40.8AP1 AP2 AP3 AP4 AP5 AP6 AP7

CP1CP2 CP3 CP4 CP5 CP6 CP7

EP2EP3 EP4 EP5 EP6 EP7

GP2GP3 GP4 GP5 GP6 GP7

IP2 IP3 IP4 IP5 IP6 IP7

JP2

KP2 KP3 KP4 KP5 KP6 KP7

LP1 LP2 LP3

MP1MP2 MP3 MP4 MP5 MP6 MP7

NP1NP2 NP3

OP2 OP3 OP4 OP5 OP6 OP7

PP2 PP3

QP2 QP3 QP4 QP5 QP6 QP7

SP2SP3 SP4 SP5 SP6 SP7

Seawater samplingBuoy-mounted sensors

Model predictions

Satellite images

~300-400 km2 after a moderate rainfall event

The Nutrient StoryPaul Gillespie, Lincoln MacKenzie, Richard Nottage, Kim Clark, Reid Forrest - Cawthron

02468

1 01 21 41 61 82 0

1 5 2 0 2 5 3 0 3 5

S a l in i ty (p su )

NO3-

-N (m

mol

m-3

)

A

0 . 0

0 . 2

0 . 4

0 . 6

0 . 8

1 . 0

1 . 2

1 . 4

1 5 2 0 2 5 3 0 3 5


DRP

(mm

ol m

-3)

B

02 04 06 08 0

1 0 01 2 01 4 01 6 01 8 0

1 5 2 0 2 5 3 0 3 5


DR

Si m

mol

m-3

C

Highest dissolved nutrient concentrations associatedwith low salinities

173 173.1 173.2

9-10 May 2001

41.15

41.05

40.95

40.85

40.75

173 173.1 173.2

9-10 May 2001

41.15

41.05

40.95

40.85

40.75DRSi Chl a

Plume-affected phytoplankton production

Periodic development of east to west gradients of nutrients and chl a dictated by river flow and water column density stratification.

173.00 173.10 173.20

9-10 May 2001

41.15

41.05

40.95

40.85 Surface Salinity

Woodstock

Woodmans BendTasman Bay

Water Quality Monitoring Sites

Flow : concentration relationships used to estimate nutrient loadings to Tasman Bay.

Nutrient Loading to Tasman Bay (tonnes/yr)

2005 2006 2007 2008 2009

0

100

200

300

400

Tonn

es p

er y

ear

0

10

20

30

40

Tonn

es p

er y

ear

8000

9000

10000

11000

12000

13000

Tonn

es p

er y

ear

DRSi

DRPTP

TNNitrateAmmonium

Nitrogen loading (tonnes/month)TNNO3NH4

0

40

80

1202009

Jan

Feb

Mar

Apr

May Jun

Jul

Aug

Sep Oct

Nov

Dec

0

40

80

120

2008

Jan

Feb

Mar

Apr

May Jun

Jul

Aug

Sep

Oct

Nov

Dec

0

40

80

120

2007

Jan

Feb

Mar

Apr

May Jun

Jul

Aug

Sep Oct

Nov

Dec

Jan

Feb

Mar

Apr

May Jun

Jul

Aug

Sep Oct

Nov

Dec

0

40

80

120

2005

0

40

80

120

2006

Jan

Feb

Mar

Apr

May Jun

Jul

Aug

Sep Oct

Nov

Dec

J F M A M J J A S O N D

J F M A M J J A S O N D

Good or bad for Tasman Bay?

• Motueka TN discharge (average 2005-2009) = ~283 t

• Total freshwater TN discharge (including point source discharges) = ~900 t/ year

• N loss via denitrification = ~1800 t/year

• N Inputs ~50% of assimilation capacity

• Problems associated with eutrophication unlikely

• Nutrients probably having beneficial effects on productivity

• But there still could be some effect on HAB incidence???

Delineation of the depositional footprint of the river plume

Deanna Clement, Reid Forrest, Chris Cornelisen, Barrie Forrest,

Paul Gillespie – CawthronBarrie Peake – University of Otago

Multiple indicators reveal river plume influence in a New Zealand coastal embayment

Barrie Forrest, Paul Gillespie, Chris Cornelisen-Cawthron, Karyne Rogers-GNS

Pilot study

Various indicators (chemical, geological, biological) were used to delineatethe spatial extent of river plume influence

Copper

Chromium

Nickel

Natural catchment source of elevated sediment trace metals

Unexpected result: Contaminated levels of Ni & Cr in plume sediments

Benthic characteristics considered for delineation of catchment influences

• Trace metal concentrations (Al, Ba, Cr, Cu, Ni, Pb, Sr, V, Cd)

• Organic content (ash free dry weight)

• Grain size - % gravel, sand, silt/clay

• Infauna abundance & diversity

KEY SEDIMENT INDICATORS OF RIVER PLUME INFLUENCE

!

!

!

!

!

!!

!

!!

!! !

!

!

!

!

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±

0 5 102.5Kilometres

Depth Contours10.0020.0030.00

Trace Metal Concentrations x 21

2

345

678

910

!

!

!

!

!

!!

!

!!

!! !

!

!

!

!

!

!

!

±

0 5 102.5Kilometres

Depth Contours10.0020.00

30.00Organic matter and Lead

12

3

45678

910

!

!

!

!

!

!!

!

!!

!! !

!

!

!

!

!

!

!

±

0 5 102.5Kilometres

Depth Contours10.0020.0030.00

Species Diversity1

2

3

4

5

6

7

8

9

10

Trace metals Organic matter & lead

Infauna diversity (SW)

Shell debris (considered non plume-related)

Shell debris (considered non plume-related)

180 km2 river plume depositional

area

based on

composites of multiple benthic

indicators

±

0 5 102.5Kilometres

Depth Contours10.0020.0030.00AMAsSediment Plume Extent

Aquaculture management areas

Tasman Bay

Suspended sediment effects on shellfish

Paul Gillespie - Cawthron

Fish & shellfish resources/activities potentially influenced by the river plume

• Enhanced scallop fishery

• Dredge oyster fishery

• Trawl fishery (flounder and sole)

• Recreational fisheries

• Mussel farming

70,000-800,000 tonnes (mean~370,000)

Annual Suspended Sediment Contributions to Tasman Bay

Loading data provided by Les Basher - Landcare

Motueka R. SS Plume - the day after a moderate flood event

SS mobilisation and export from nearby estuaries - strong winds during spring high tides, no rain

Frequent SS plumes occur in Tasman Bay under a variety of weather conditions.

Sediment Mobilisation

Cumulative impacts?

SS Effects on Benthic Suspension Feeders

• SS inhibition of scallop feeding

o Near‐bottom (50 mm above the seabed) SS concentrations of 11‐25 g/m3 (89‐96% inorganic)were seen to interrupt the feeding activity of scallops on the seabed

o Scallops in baskets 0.5 or 1.0 m above the seabed continued feeding normally

Potential effects on shellfish resources in Tasman Bay

•Chronic condition of high near-bottom turbidity

Physical disturbance due to dredging & trawling

Deposition/ Resuspension

• Scallop catches (tonnes)• No harvests 2005/06 ‐

present

Interference of scallop feeding

0

100

200

300

400

500

600

89/90 91/92 93/94 95/96 97/98 99/00 01/02 03/04

?

Tracking faecal contaminants in the Motueka River plume

Chris Cornelisen

173.00 173.10 173.20

41.15

41.05

40.95

40.85

•Sedimentation•Contaminants (faecal, nutrients,metals, hydrocarbons, etc)

Turbidity

Bacteria

River flows

0100

200300

400

500

Flow

(cum

ecs)

0

100

200

300

NTU

0

2000

4000

6000

8000

28-Apr 29-Apr 30-Apr 01-May

MPN

/100

ml

Bad weather

0

10

20

22-Apr 23-Apr 24-Apr 25-Apr 26-Apr 27-Apr 28-Apr 29-Apr 30-Apr 01-May 02-May 03-May 04-May 05-May 06-May 07-May

Win

d sp

eed

(m s

-1)

0

10

20

30

40

Rai

nfal

l (m

m)

Wind speedRainfall

High riverDischarge

River flow (Woodmans bend)

0

200

400

600


m3 s

-1

Increase in turbidity coincidingwith winds

05

1015202530


Turb

idity

(NTU

)

-5-3-11357

Am

plitu

de (m

)

Turbidity (3 km)Turbidity (6 km)Tide

Mixing andpersistence of shallow low salinity plume

30

32

34

36


Salin

ity (p

su)

12

14

16

18

Tem

p (C

)

Salinity (3 km) Salinity (6 km)Temperature (3 km) Temperature (6 km)

Shading by thin surface layer of fine sediment

0300600900

12001500


PAR

um

ol m

-2 s

-1

Incoming3 m depth

Sal

inity

at

Dep

th, m

29-Apr-2009 23:36:21

0

5

1025

30

35

Tem

pera

ture

at

Dep

th, m

0

5

1015

16

17

Ligh

t at

Dep

th, m

0

5

101

10

100

1000

ty a

t m

0

54

Tem

pera

ture

at

Dep

th, m

0

5

1015

16

17

Ligh

t at

Dep

th, m

0

5

101

10

100

1000

Turb

idity

at

Dep

th, m

0

5

100

2

4

Distance from river mouth, km

Chl

orop

hyll

atD

epth

, m

1 2 3 4 5 6

0

5

100

2

4

CTD and water quality survey – 30 Apr 2009

Mussel results here

0

50

100

150

1 2 3 4 5 6Distance from river mouth (km)

MPN

/100

ml E. coli

Enterococci

Mussel results hereE.coli

0

500

1000

1500

1.5 km 2 km 6 km (AMA)

MPN

/100

g 30-Apr07-May

Enterococci

0

500

1000

1500

2000

2500

1.5 km 2 km 6 km (AMA)

MPN

/100

g

Ruminant Bacteroides (Bac128)1 to 2 km 6 km

(AMA) + ‐

Human Bacteroides (Bac183)HumanMethanobrevibacterHuman Polyomavirus (HPyV)

3 human markers not detected

Humans0.2%

Poultry1.3%

Horse0.5%

Deer(farm)0.7% Possum

0.6%

Cattle80.9%

Sheep15.4%

Pig0.4%

NZ’s PPP: Potential poo production (not including “wildlife”)

Where’s it coming from?Microbial Source Tracking

Continuing efforts

Real-time monitoring

•Telemetry-data accessibility•Real-time Environmental Sample Processing (ESP)

Molecular tools

•MST tools for water quality monitoring•MST tools for ensuring shellfish quality•Quantitative PCR•DNA probe arrays

Acknowledgements

NIWA: Rob Davies-Colley, Rob Merrilees, Murray Hicks

Cawthron: Paul Gillespie, Marek Kirs, Roger Young, Reid Forrest, Paul Barter, Aaron Quarterman, Eric Goodwin, Ben Knight, Ron Fyfe, Mark Englefield

Valerie (Jodie) Harwood, University of South Florida

marine component of icmicm.landcareresearch.co.nz/knowledgebase/publications/...ap1 ap2 ap3 ap4 ap5...

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