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Approaches to Ecological Assessment Models R Us Handout # 5
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2 Class Objective 1.Provide student with a understanding of the relationship of models to their job and to Corps projects. 2.Provide student with an overview of general approaches. 3.Review homework assignment. 4.Describe key procedures: HEP, IFIM, IBI, HGM.
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3 What is your job? The Corps objective: to contribute to (NER) increases in net quantity and/or quality of desired ecosystem resources. –Measurement of NER is based on changes in ecological resource quality as a function of improvement in habitat quality and/or quantity and expressed quantitatively in physical units or indexes (but not monetary units).
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Discuss Homework Best professional judgment WRAP HEP HGM IBI Which can be used as input to Incremental Cost Analysis?
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5 General approaches How to assess function? 1. Best professional judgment (Descriptive narratives) 2. Measure specific criteria (e.g., water quality input/output, biomass, fish and wildlife populations) 3. Assessment procedure (structured bpj models) (Handout # 5)
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6 1. Best Professional Judgment Simple statements or icons –Function present or absent –Screening tool Narrative (usually cite literature) Rating (e.g., index, score 1-5, low, moderate, high ) Discuss example of bpj developed in the class exercise (i.e. WRAP Handout # 3 pg 1)
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7 Comments: Best Professional Judgment Advantages: Usually more rapid and cost effective. May reveal things overlooked by other approaches. Disadvantages: Generally lacks documentation to support rating. Lack of set criteria leads to different scoring of same site by different observers. Less defensible.
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8 2. Specific Criteria Identify and measure specific structural or functional criteria based on areas of concern. Examples: Surveys for rare and endangered species Water quality (nutrient levels, oxygen levels, turbidity, temperature) Sediment sampling for contaminants
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9 3. Ecological Assessment Procedure No models - best professional judgment. with a Descriptive Approach; i.e. some structure. (e.g.) WRAP. Models - that describe function based on ecological structure (minimal sampling of organisms if any). (e.g., HEP, HGM). Models - that describe habitat based on population data (extensive sampling of organisms). (e.g., IBI). Scale/context differ: landscape, ecosystem (site level), community models, or species specific. (Handout #6)
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Review of key procedures Habitat Evaluation Procedure (HEP) Instream Flow Incremental Methodology (IFIM) Index of Biological Integrity (IBI) “Wetland assessment”: Many including the Hydrogeomorphic Approach(HGM) Handout # 5
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11 All of These Procedures Require Field Sampling For small project visual recon is okay. Large projects need randomized sampling. The sample represents the quantification of a subset of the whole multiplied by the spatial extent. A sampling exercise will be conducted with the cultural resources module.
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12 HEP Provides a numerical index incorporating food, cover and breeding relationships indicative of a habitat’s carrying capacity for a given species.
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13 HEP Habitats: Upland, wetland,and aquatic habitats Measures: habitat suitability Units: HSI and HUs Handout #4 page 5
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16 HEP Strengths: Objective Quantitative Standardized nationwide Models tested and available Can compare different habitats Limitations: Habitat only Can manipulate result by changing species Time consuming Does not address functions.
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17 Instream Flow Incremental Methodology (IFIM) Instream flow methodology deals with the amounts of streamflow necessary to sustain instream values at acceptable levels.
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18 PURPOSE: To assesses stream flow and stream habitat utility utilizing macro- habitats variables including temperature, water quality, channel structure, and measures of micro- habitat variables such as velocity, depth, and cover. IFIM ( Instream Flow Incremental Methodology)
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20 Stream Transects = Hydraulic Controls * Hydraulic controls form upstream an downstream boundaries of each cell. *
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21 Use computer programs, e.g., PHABSIM* and HABITAT 1 2 3 * * Habitat Cells Hydraulic Cell
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22 IFIM
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23 IFIM Strengths Looks holistically at the species year-round life requirements Quantifies habitat values at differing flows Limitations Expensive Limited number of models Cold Water Origins
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24 PURPOSE: To assess the biological integrity (level of disturbance) of a habitat through samples of living organisms to evaluate the consequences of human actions on biological systems. IBI ( Index of Biological Integrity)
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25 IBI ( Index of Biological Integrity) Habitats: streams, mud flats, wetlands, and deepwater habitats Measures: biological integrity Units: IBI IBI = sum of metric* scores * A parameter with predictable and empirical patterns when plotted against a gradient of human disturbance.
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26 Disturbed –Damaged Healthy Same Habitats Type Same Habitat Type
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27 Collecting organisms from selected assemblage (e.g., macroinvertebrates) Activity Trap Fixed Area Sample Dip Net
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28 Example of a Metric
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29 Scoring a Metric
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30 Example of Multiple Metrics AB Wisconsin IBI
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31 Different assemblagesAmphibians Fish Macroinvertebrates Birds Algae Vascular Plants
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32 IBI Strengths: Direct measurement of biological integrity Accounts for multiple stressors Chemical, physical, & biological Helps to diagnose stressor(s) impacting biota Limitations: Shortage of most models Non-biological functions not assessed e.g., flood storage, erosion control Time consuming Cannot compare different habitat types
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33 HGM (Hydrogeomorphic Approach) Purpose: The HGM Approach utilizes reference wetlands as the means for establishing a scale, or index, against which other wetlands of the same type in a particular geographic area (reference domain) can be compared to determine their functional capacity.
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34 HGM (Hydrogeomorphic Approach) Habitats: Wetland Measures: Functional capacity Units Units: FCI and FCU 1 FCI x 1 acre = 1 FCU Functional Capacity Index: A comparison of how well other wetlands in the region perform a particular function.
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35 HGM Approach Strengths: Objective Quantitative Several functions Standardized nationwide Rapid once models ready Limitations: Model development time consuming Cannot compare different wetland classes Need to develop most models
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36 Different purposes establish the basis for different approaches...... thus leading to separate procedures.
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37 Some of the Many Wetland Assessment Procedures AREM Coastal Method CT Method Descriptive App. EPW HAT HEP HGM Approach Hollands-Magee IBI Interm HGM IVA Larson Method MDE Method ME Tidal Method MN RAM MT Form NBM NC-CREWS NC Guidance NEFWIBP NH Method NJ Watershed Method OFWAM PAM HEP PFC RA Rapid Assess Meth. Synoptic Approach VIMS Method WAFAM WCHE WET WEThings WHAMS WHAP WIRAM WQI WVA WRAP
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38 Approaches used by other Districts Elizabeth River, Norfolk: - One HEP species (clapper rail) and best professional judgment for 7 functional values DesPlains River, Chicago - floristic quality index, HEP, HGM, …… South River, New York – HEP and EPW St. Louis District – WHAG and AHAG. East St. Louis project - HEP, tried HGM New River, Huntington –IFIM Whitney Point, Baltimore District – IFIM
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39 Sage Advice Many ways to assess (bpj and beyond…). Carefully define your objectives. See what is used in your division. Always explore other possibilities. Finally note that environmental windows also apply to field data collection.
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