GA-DNR: GADNR Invert 2007: Macroinvertebrate Collection Method for Wadeable Streams in Georgia
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Official Method Name
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Macroinvertebrate Biological Assessment of Wadeable Streams in Georgia |
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Current Revision
| Version 1.0, March, 2007 |
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Media
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Biological (Waterbody type - Wadeable stream) |
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Instrumentation
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Invertebrate Net (w/ handle) |
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Method Subcategory
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Population/Community |
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Method Source
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Citation
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Protocol
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GADNR Invert 2007 - Macroinvertebrate Biological Assessment of Wadeable Streams in Georgia |
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Brief Method Summary
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The Standard Operating Procedures (SOP) Manual is designed to describe and document the Georgia Department of Natural Resources, Environmental Protection Division’s (EPD) operations associated with aquatic macroinvertebrate biological monitoring in wadeable streams.
After the water chemistry data has been collected, the next step is to collect the benthic macroinvertebrates using a D-frame net. Samples are collected throughout the 100-meter reach. Make sure the sampled habitats are distributed throughout the reach. Macroinvertebrate collection should be conducted with two team members. One individual will collect the samples using a D-frame net. The other member will keep up with the number of jabs, compiling the material in the sieve bucket, checking large debris for organisms, and elutriating the sieve bucket to reduce the amount of silt in the sample. After sampling is complete, the debris will be placed into plastic sample containers and the Benthic Macroinvertebrate Field Data sheet (see p.2A-20) and the internal and external sample labels must be filled out completely. |
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Scope and Application
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The primary purpose of this document is to establish and maintain uniform methodology and quality control guidance for biological data collected within the state. Compliance with these procedures is essential to produce reliable biological data. This document is intended for use as a training resource for all Ambient Monitoring Unit sampling employees as well as a technical manual to be used as a reference for study plans and reports. Deviations from this SOP manual should receive prior approval from EPD staff and be explained and documented.
The biologically optimal sampling season would occur when the habitat is utilized most heavily by later instars and the food resource has stabilized to support a balanced indigenous community (Plafkin et al., 1989). Biologically optimal periods start in the fall and continue through winter. Georgia’s Index Period for sampling is mid-September through February. If the study objective is to document stream conditions due to improvement of wastewater treatment, removal of a treatment system, etc., then the biological evaluation could be limited to one sampling event during periods of greatest environmental stress such as low flow, high temperature periods for point source discharges or high flow, runoff periods for nonpoint source discharges. Assessment of worst-case conditions may be needed under certain permitting regulations, or as a follow-up to sampling during biologically optimal periods, where impairment is detected (Plafkin et al., 1989). In evaluating the success of a Best Management Practice (BMP), it is necessary to compare pre-improvement biological conditions to post-improvement biological conditions. Thus, sampling strategies should be designed to allow such comparison. |
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Applicable Concentration Range
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Interferences
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Quality Control Requirements
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Sample Handling
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Maximum Holding Time
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Relative Cost
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Unknown |
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Sample Preparation Methods
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