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Czernin, unpublished data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!