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7.4 Algal Biomass Indicators (8/2007) [1MB PDF]
By Julie A. Hambrook Berkman and Michael G. Canova
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Indicators of algal biomass are used to assess water quality in both moving (lotic) and stillwater (lentic) ecosystems. Algal biomass in a water body can be estimated in three ways: (1) by quantifying chlorophyll a (CHL a), (2) by measuring carbon biomass as ash-free dry mass (AFDM), or (3) by measuring the particulate organic carbon (POC) in a sample. The CHL a procedure measures photosynthetic pigment common to all types of algae, while AFDM and POC procedures measure the carbon in a filtered water sample.
7.4 Algal biomass indicators
7.4.1 - Pre-sampling considerations and plans
7.4.2 - In vivo measurement of chlorophyll and phycocyanin
7.4.3 - Phytoplankton sampling procedures for chlorophyll a and particulate organic carbon
7.4.4 - Periphyton sampling procedures for chlorophyll and ash-free dry mass in streams, lakes, reservoirs, and large rivers
7.4.5 - Sample processing and preservation
7.4.6 - Field-data documentation, labeling, and sample packaging and shipping
7.4.7 - Selected references for algal biomass indicators
7.4.8 - Acknowledgments
Appendix A7-A - Examples of field forms
Citation for Section 7.4
Hambrook Berkman, J.A., and Canova, M.G., 2007, Algal biomass indicators (ver. 1.0): U.S. Geological Survey Techniques of Water-Resources Investigations, book 9, chap. A7, section 7.4, August, accessed__date__ from http://pubs.water.usgs.gov/twri9A/.