Chris Phillips Roger Young, Mike Marden, Rob Davies-Colley, Lisa Langer

The Motueka Riparian Management Project

Outline

• issue(s)• context - background • progress to date

– riparian plant coloniser trial – riparian typology– ecology of turbid streams– functional biodiversity– in-stream processes & productivity

• where to next?

• Improving biodiversity

• Carbon – natives, Kyoto

• Natives on farmland

• Greening “our” place

• Catchment intervention point – functions

• Improving water quality

Issue - drivers

Context

• Catchment – stream health

• Intervention point – riparian

• What’s there?

• What’s the condition?

• What are the functions?

• Can we do anything about it?

• What would we do, and where?

Native Plants for stream Native Plants for stream bank stabilisationbank stabilisation

Progress - Part 1Progress - Part 1

Riparian coloniser trial

• SpeciesCommon Botanical Name name

Karamu Coprosma robustaRibbonwood Plagianthus regiusKowhai Sophora tetrapteraLemonwood Pittosporum eugenoides

Kohuhu Pittosporum tenuifoliumLacebark Hoheria populneaMapou Myrsine australisFivefinger Pseudopanax arboreusCabbage tree Cordyline australisRewarewa Knightia excelsaManuka Leptospermum scopariumTutu Coriaria arborea

• Field trial

• Architecture – Canopy spread– Root depth– Lateral root spread

• Biomass partitioning– Above-ground– Below-ground

Sorted on Year 2 data

tutukowhai

fivefingerkaramu

lemonwoodrewarewa

kohuhumapou

cabbage treemanuka

lacebark

ribbonwood

Mea

n r

oo

t d

epth

(cm

)

0

10

20

30

40

50

60

Year 1Year 2

Root depth

Root spread

Year 1Year 2

Sorted on Year 2 data

kohuhufivefinger

lemonwoodkowhai

mapoulacebark

cabbage treekaramu

rewarewamanuka

ribbonwood tutu

Mea

n r

oo

t sp

read

(cm

)

0

10

20

30

40

50

Year 1Year 2

Biomass

Sorted on Year 2 below ground data

l emonwoodkohuhu

r ewar ewakowhai

l acebar k t ut ukar amu

mapoumanuka

f i vef i nger

cabbage t r ee

r i bbonwood

Ab

ove

an

d b

elo

w g

rou

nd

mea

n b

iom

ass

(g)

-100

-50

0

50

100

150

Year 1 above groundYear 1 below groundYear 2 above groundYear 2 below ground

Top of the class?

1 year old 2 year old

m

m

1 year old 2 year old 3 year old

Cabbage tree – Cordyline australis

Czernin, unpublished data

Riparian Typology for Riparian Typology for the Motueka River Catchmentthe Motueka River Catchment

Progress - Part 2Progress - Part 2

Methods - general

• 156 stream sections examined• Big rivers and small streams• Reasonable geographic spread• Not in the mountains – DOC land• Access a key criteria• John Quinn’s methodology• Rapid assessment – 40 mins • Feb – March 2001 - drought• Statistical analyses not completed• Map of types not done yet

Rainy

Motueka

Wangapeka

TadmorSherry

Dart

Motupiko

Baton

StanleyBrook

Dove

Orinoco

Wai-wheroPearse

Graeme

Pokororo

Brooklyn

Red Hills

Rainy

Motueka

Wangapeka

TadmorSherry

Dart

Motupiko

Baton

StanleyBrook

Dove

Orinoco

Wai-wheroPearse

Graeme

Pokororo

Brooklyn

Red Hills

Kahurangi Nat Park

Results – general

• Many low order streams dry• Rosgen useful• Geomorphic control > landuse control• Substrate variable – fines downstream• Riparian veg. generally poor in non-forest areas• What’s there is narrow - 1 or 2 trees deep• Natives very low – mostly willows/weeds

Results – stock

Stock access to stream LBStock access to stream LB 44%44%

Stock access to stream RBStock access to stream RB 41%41%

Stock damage to bankStock damage to bank

None

Minor

Moderate

Extreme

Results - fencing

Fenced

Fence type

None

Fenced

Electric

Post/batten

Results – Woody debris

Absent

Sparse

Common

Abundant

Results Current Potential

Bank Stability 3.3 4.3 Overland flow 2.7 3.8 Nutrient 2.0 2.9 Denitrification 1.0 1.6 Shade for temp control 2.5 4.0 Shade for plants 2.5 3.9Wood 1.7 3.1 Litter 2.4 3.7 Fish habitat 2.8 3.3 Flooding reduction 1.8 2.1 Recreation 2.3 2.8 Aesthetics 2.3 3.8

1 5GoodPoor

Ecology of Turbid StreamsEcology of Turbid StreamsProgress - Part 3Progress - Part 3

StudyAreas -

Waiapu &Waipaoa

Catchments

N 0 30 km

Ruatoria

Gisborne

East Cape

Temperature records - forest vs pasture stream

5

10

15

20

25

30

3-2 4-2 5-2 6-2 7-2

Te Arai River: Bush vs Pasture

Temp.

( oC)

Date 2000

Criterion for stoneflies

Torrentfish

Fish - sediment relationship

0 1 2 3 4 5 6No. of fish spp

1.0

10.0

100.0

1000.0

Sus

pend

ed s

edim

ent (

g/m

3 )

Fish-eye photograph of riparian

shade(pasture stream)

Interim Results

• Native Streams -• good water quality

• diverse biology - high “stream health”

• Pasture streams - “degraded”• very poor water quality

• “tolerant” animals dominate - “low stream health”

• Pine plantation streams - • in better “shape’ than pasture streams

Where to next?

• complete map of the river habitat • continue native plant trial• measure stream health - habitat quality - riparian

condition at representative sites • determine the distribution of native fish• role of intact riparian vegetation in controlling

sediment supply • role of riparian vegetation for stream habitat • rapid techniques for assessing riparian veg. • conduct a riparian intervention experiment

Last slide – phew!