1. National Monitoring Conference May 7-11, 2006
Effects of Hydrologic and Environmental Factors on Ecological Conditions of Upland Streams in the Northeast, USA.
National Monitoring Conference
May 7-11, 2006
Jonathan G. Kennen, NJWSC, West Trenton, NJ
Karen R. Murray NYWSC, Troy, NY
Karen M. Beaulieu, CTWSC, East Hartford, CT

2. There are many mechanisms by which hydrology impacts biota.
Requirements
Stressors
Sources
High Water
Temperature
Poor Riparian
Buffers
Poor Riparian
Buffers
Healthy
Water
Chemical
Pollutants
Point Sources
High Turbidity
Construction
Substrate
Suitability
(low DO)
Sedimentation
Channel Erosion
Refugia
Physical Habitat
Insuf. Woody Debris
Historic Sediment
Interstitial
Habitat
Impervious
Surfaces/ Stormwater
Altered Flows
(algal bloom)
Excess Nutrients
Livestock & Poultry
Use of Pesticides & Fertilizers
Altered Food Webs
Food (Algae,
Meiofauna)
Invasive Species
Introductions
Excess Competitors
Few Competitors & Predators
Excess Predators
Reservoirs
Connections to
Other Populations
Road
Crossings
J. Kennen, NJWSC, West Trenton, NJ
Movement Barriers

3. Multiple stressors can have additive and/or synergistic effects? + x –

4. Stream hydrology differs – can have linear, threshold, or even a delayed response to disturbance?
biotic integrity
disturbance ?
biotic integrity
disturbance

5. “I asked you a question buddy, what’s the minimum flow we need to protect aquatic species in this here Basin?”

6. Project Objectives
Identify important environmental and hydrological parameters
Discern disturbance gradient from biota
Describe relations with observed ecological patterns
Use sound science to identify key variables water managers can use to improve stream quality

7. Scope 77 upland watersheds Range of urban intensity
7 NAWQA study units

8. Data Requirements Quantitative invertebrate riffle samples
Gaging station co-located at or near aquatic invertebrate sampling site
Hydrologic data needed for a minimum of 3 or more years
Quantitative invertebrate riffle samples
Gaging station co-located at or near aquatic invertebrate sampling site
Hydrologic data needed for a minimum of 3 or more years
Quantitative invertebrate riffle samples
Gaging station co-located at or near aquatic invertebrate sampling site
Hydrologic data needed for a minimum of 3 or more years

9. Data Compilation
Hydrologic descriptors (Hydrological Integrity Assessment Process –171 Variables)
Quantitative invertebrate (density –numbers/m2)
Assemblage metrics and indices
GIS Data –“Roads Corrected” Land use / cover, etc.

10. General Analytical Approach
Environmental Variables
PCA/Corr. [=data reduction]
Final Set of Variables
(Standardize, Transform, Assess Colliniarity)
(>527 vars.)
(76 vars.)
Invertebrate Data
Ordination (NMDS)
Extract Axis Scores
Multiple Linear Regression (MLR)
(Axis Score = disturbance gradient)
(+/- 37 vars.)

11. Why use Ordination?
Reduces complexity of community data while retaining structure
Derives environmental gradients based on biota
Places sites with similar communities close together, those with dissimilar communities far apart

12. Disturbance Gradient Concept
Excellent
High Ecosystem
Integrity
Very Good
Good
Assemblage Condition
Fair
Poor
Low Ecosystem
Integrity
Very Poor
Natural
Minimal
Moderate
High
Serious
Radical
Anthropogenic Disturbance

13. Distribution of Sites Coded by Relative Position Along the Disturbance Gradient
Level of Disturbance
High
Moderate
Minimum
Very High
NE Ecoregions

14. Ordination Color Coded (high to low) by Percent Riparian Forest
% Rip. Forest
Low
Medium
High
Disturbance Gradient

15. Relations with assemblage structure and function
Richness of Sensitive EPT Taxa
Dist. Grad.
Dist. Grad.
Richness of Tolerant Taxa
Strong relations with metrics further support interpretation as a disturbance gradient.

16. Relations with Land Use & Configuration
Decline in Core Forest
Dist. Grad.
Relations show the extent of anthropogenic effects and help target attributes that may be useful from a LU planning perspective.
Decline in % Riparian Forest
Dist. Grad.

17. Relations with assemblage structure
Tolerant species increase
Sensitive species decrease

18. Regression Model using Disturbance Gradient as Response Variable
Results of significant (p<0.05) MLR model –disturbance gradient is response variable

19. Example –Percent Riparian Forest
EPT Richness
Significant linear relations observed –no defined inflection point.
% of Omnivores
Variability of January Flow

20. Summary of Findings
Patterns in biota are highly related to stream degradation.
Environmental alterations are related to changes in the biotic integrity across a disturbance gradient.
Riparian forest areas lessen the effects of human-induced landscape and hydrologic alterations.
Intolerant taxa become less prevalent as streams become more degraded.

21. Management Implications
Relations between invertebrate assemblage metrics and environmental and flow attributes can be used to:
target levels of riparian coverage that are protective of structural complexity and/or meet designated aquatic life use
or. . target portions of the flow regime that are protective of biological integrity

22. Management Implications