EPA-OW: NRSA Invert 2009 (Wade): Benthic invertebrate sample collection in small wadeable streams
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Official Method Name
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Section 6.4: Wadeable streams-Benthic Macroinvertebrates (of National Rivers and Streams Assessment: Field Operations Manual (2009)) |
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Current Revision
| 2009 |
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Media
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WATER (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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EPA-841-B-07-009 - National Rivers and Streams Assessment: Field Operations Manual (2009) |
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Brief Method Summary
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This method is in USGS BioData as BERW for reach-wide benthos and as ILGB-W for low-gradient benthos. Collect benthic macroinvertebrate composite samples using a D-frame net with 500 um mesh openings. Take the samples from the sampling stations at the 11 transects equally distributed along the targeted reach. Composite all sample material and field-preserve with about 95% ethanol. This method also includes procedures for high and low gradient streams. |
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Scope and Application
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Methods described in this document are to be used specifically in work relating to the National Rivers and Streams Assessment. This document contains proceedures for how to collect benthic macroinvertebrate samples. |
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Applicable Concentration Range
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Interferences
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Completely fill the jar with 95% ethanol (no headspace). It is very important that sufficient ethanol be used, or the organisms will not be properly preserved. Existing water in the jar should not dilute the concentration of ethanol below 70%. |
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Quality Control Requirements
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Collect a sample from 1-m downstream of each of the 11 crosssection transects at the assigned sampling station. |
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Sample Handling
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Replace the cap on each jar. Slowly tip the jar to a horizontal position, then gently rotate the jar to mix the preservative. Do not invert or shake the jar. After mixing, seal each jar with plastic tape. |
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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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An additional separate sample will be taken at low gradient streams to include edge habitat (leaf litter, organic deposits, undercut banks, root wads, macrophyte beds, etc.) |
