the importance of healthy riparian areas and their current status in wisconsin
DESCRIPTION
The Importance of Healthy Riparian Areas and their Current Status in Wisconsin Tim Asplund, Buzz Sorge (WI DNR) Advanced Lake Leaders – Green Lake Sept. 26, 2013. Courtesy of MN DNR. Lakeshore zone. Shallow zone. Complexity: - PowerPoint PPT PresentationTRANSCRIPT
The Importance of Healthy Riparian Areas and their Current Status in Wisconsin
Tim Asplund, Buzz Sorge (WI DNR)
Advanced Lake Leaders – Green Lake
Sept. 26, 2013Courtesy of MN DNR
Lakeshore zoneShallow zone Complexity:
The degree to which both lakeshore and shallow zones are intact.
Complex habitats facilitate movement of food into and out of lakes, provide shelter and nesting areas for fish an wildlife, and buffer human impacts.
Disturbance:
Shorelands and Shallows
Shorelands and Shallows
Shorelands and Shallows
Shorelands and Shallows
SHORELINE DEVELOPMENT
Shoreland Assessments• Riparian Habitat
– Vegetation cover– Shoreline and bank– Trees and shrubs
• Littoral Habitat– Bottom substrate– Aquatic plants– Fish habitat
• Human Influences– Docks, piers, seawalls– Buildings, lawns, driveways
Data: U.W. BioComplexity project
logGrowthRate(mm/yr)
Woody Habitat (no./km)
High Development
Low Development
Undeveloped
High Development
Low Development
Undeveloped
From Schindler et al. 2000
Fish grow ~3X faster in lakes with lots of woody
habitat
FLOATING-LEAF VEGETATIONFLOATING-LEAF VEGETATION
20
25
30
35
40
45
50
2 4 6 8 10 12 14 16 18 20
Dwellings per km of shoreline
FQ
I Sc
ore
0
20
40
60
80
100
120
140
2 4 6 8 10 12 14 16 18 20
Dwelling per km of shoreline
Fre
quen
cy o
f oc
curr
ance
of
floa
ting
veg
etat
ion
10
15
20
25
30
35
40
45
50
2 4 6 8 10 12 14 16 18 20
Dwellings per km of shoreline
Num
ber
of p
lant
spe
cies
per
la
ke
Jennings et al 2003Jennings et al 2003
Shorelands and Shallows
Shorelands and Shallows
Shorelands and Shallows
2007 National Lake Assessment
Poor Biology is Three Times More Common when Lakeshore Habitat is Poor
Regional summary:• Northern Plains, Coastal
Plains and Xeric have highest proportion of lakes with poor habitat conditions
• While Northern Appalachian exhibits the highest proportion of lakes with high-quality habitat, > 25% of lakeshores are in poor condition
NLA Physical Habitat and Human Disturbance Indices
• Riparian (Lakeshore) Vegetation Cover Index
• Littoral Habitat Cover Index• Littoral Habitat and
Lakeshore Vegetation Complexity Index
• Riparian Disturbance Intensity and Extent Index
• Bottom substrate• Aquatic macrophytes• Fish cover
• Canopy• Understory• Ground cover• Shoreline substrate• Human influence
• Bank features• Invasive species
Littoral Zone
Riparian Zone
Both
Protocol
Condition of the Nation’s Lakes: Habitat
Stressors to the Nation’s Lakes:Extent, Relative Risk, and Attributable Risk
• #1 – Lakeshore vegetation: Poor biology is three times more common when lakeshore vegetation cover is in poor condition. This affects 36% of lakes.
• #2 – Nutrients: Poor biology is 2.5 times more common when nutrients are high. This affects about 20% of lakes.
Riparian Disturbance
pHab: Riparian Disturbance Index
0% 20% 40% 60% 80% 100%
Nation
Region
MN
WI
MI
NLA 2007 Weighted Percentage
High Mid Low Missing
pHab: Riparian Disturbance Index
Missing Low Mid High
Littoral Cover Index
pHab: Littoral Cover Index
0% 20% 40% 60% 80% 100%
Nation
Region
MN
WI
MI
NLA 2007 Weighted Percentage
High Mid Low Missing
pHab: Littoral Cover Index
Missing Low Mid High
Lakes sampled for shore habitat in 2012 and 2013
Goals of 2013 National Lake Assessment Lakeshore Sampling
1) expand the assessment of lakeshore habitat condition across Wisconsin
2) analyze lakeshore habitat condition in terms of lake area and surrounding land use
3) Compare macrophyte survey methods: point-intercept vs. transect
4) develop ecoregion-specific lakeshore habitat metrics for Wisconsin
5) Incorporate lakeshore habitat metrics into WisCALM and Citizen Lakes Monitoring
6) use lakeshore habitat metrics in addition to trophic status to assess lake health
• Restoring Complexity and Functional Values of Shorelands