Monitoring Wetland Health in the Credit River Watershed€¦ · Monitoring Wetland Health in the...
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Monitoring Wetland Health in the Credit River Watershed Preliminary Results and Trends Aviva Patel
Transcript of Monitoring Wetland Health in the Credit River Watershed€¦ · Monitoring Wetland Health in the...
Monitoring Wetland Health in the Credit River Watershed
Preliminary Results and TrendsAviva Patel
Terrestrial Monitoring Goals
Identify status and trends in wetland health parameters at the watershed scale, link to watershed health
Identify spatial patterns in wetland health parameters
Provide meaningful data on which watershed management decisions can be based
Why Monitor Wetlands?
• Wetlands provide numerous functions:– Flow moderation– Water purification– Erosion control – Carbon sequestration
• Wetland Monitoring allows:– Detection of habitat loss
or degradation– Adaptive environmental
management
Credit River Watershed
Credit Valley Watershed
• Physiographic Zones– Lower: Heavily urbanized– Middle: Niagara
Escarpment & Oak Ridges Moraine
– Upper: Urban, agriculture and natural
• Monitoring Sites– 18 Vegetation Sites– 26 Amphibian Sites
Wetland Indicators
Wetland Health
Landscape
Vegetation
Wildlife
Regeneration Ground cover
Marsh birds Amphibians (frogs & toads)
Water
4 years
6 years
Wetland Cover• 6% of watershed area• <3% in Lower Watershed• Fair – Good in Middle and
Upper Watersheds• ~48% wetland loss since 1954• 81% swamp, 18% marsh
0200400600800
1000120014001600
0-1 1-4 4-10 10-30 30-50 50-100 >100
Wetland size class
Freq
uenc
yWetland size
Majority of wetlands <1ha but these contribute only 25% of total wetland area
75% of area
(ha)
Vegetation - Methods
• EMAN & CVC Methodology
• 50 m transect
• 12 subplots
• 2 x 2 m Regeneration
• 1 x 1 m Vegetation
• All taxa identified to species& percent cover recorded
Vegetation - Indicators
– Richness– Diversity– Locally and Regionally
rare species– Floristic Quality
Assessment• Mean Coefficient of Conservatism (mCC)• CC 8-10• Average Wetness• Average Weediness• Weediness Score -3
Vegetation - Results
• 465 herbaceous and woody plants identified to species level (37% of watershed total)
8%
17%
53%
4%
2%
0%
6% 10% 0%TreeShrubForbFernVineRushGrassSedgeOther
82% native
Vegetation – species richness & diversity
• Temporal Trends
– Increasing plant species richness and diversity
• Increasing knowledge of sites
• Changes in monitoring team
Ground Vegetation
Richness
Diversity
Vegetation – native species• Temporal patterns
– Proportion of native species decreasing over time
0.76
0.78
0.8
0.82
0.84
0.86
0.88
0.9
0.92
2005 2006 2007 2008Year
Prop
ortio
n of
Nat
ive
Spec
ies
Vegetation – native species
• Spatial patterns– Proportion of native species
• Lower < Middle and/or Upper
0.50
0.60
0.70
0.80
0.90
1.00
2005 2006 2007 2008
Year
Prop
ortio
n of
Nat
ive
Spec
ies
LowerMiddleUpper
Vegetation – weedy species
• Temporal patterns– Number of weedy species (Weediness score - 3) is
increasing
0
1
2
3
2005 2006 2007 2008
Year
Mea
n -3
Per
Site
Vegetation – weedy species
• Spatial patterns– -3 weedy species different among zonesLower > Middle & Upper
0
1
2
3
4
5
2005 2006 2007 2008Year
Num
ber o
f Spe
cies
LowerMiddleUpper
Amphibians - Methods
• Marsh Monitoring Program protocols
• Calls recorded to estimate amphibian numbers and species– C1 – calls not overlapping– C2 – calls overlapping– C3 – full chorus
Amphibians - Indicators
Frogs and toads:
– Richness– Abundance– Site Occupancy
0
0.5
1
1.5
2
2.5
3
3.5
4
2003 2004 2005 2006 2007 2008
Year
Spec
ies
richn
ess
per s
ite
Amphibians – trend analysis
• Nine species detected, only mink frog not detected• No observable trend in amphibian species richness,
abundance or site occupancy over the monitoring period
Amphibians – number of species per site
Amphibians – spatial analysis• Species richness varied between physiographic
regions– Lower < Middle and/or Upper
Amphibian Species Richness
00.5
11.5
22.5
33.5
44.5
5
2003 2004 2005 2006 2007 2008
Year
Spec
ies
richn
ess
per s
ite
LowerMiddleUpper
Amphibians – spatial analysis
• Spring Peeper absent from Lower zone
• No full chorus of any frog or toad species detected in Lower zone
Photo credit: Toronto Zoo
Summary
• Relatively stable plant and amphibian richness and diversity
• Relatively stable trends in plant wetness index and coefficient of conservatism
• Data suggest urbanization is affecting native biodiversity– Lower Watershed has fewer amphibian species and lower
proportion of native plants than Middle and Upper Watershed
• Increasing numbers of -3 level weedy species in watershed
Future Work
• Increase number of sites
• Panel design to minimize impact on sites
• Addition of hydrology and water quality parameters
