USGS-NWQL: B-3520-85:  Periphyton, Biomass, Dry Weight, total and Ash Weight

  • Summary
  • Analytes
  • Revision
  • Data and Sites
Official Method Name
Gravimetric Method for Biomass
Current Revision
1985
Media
WATER  (Waterbody type - Wadeable stream)
Instrumentation
Gravimetry
Method Subcategory
Biochemical
Method Source
  USGS-NWQL
Citation
  National Field Manual for the Collection of Water-Quality Data: USGS Techniques of Water-Resources Investigations Book 9, Ch. A4: Collection of Water Samples.
Brief Method Summary
Samples of the periphyton community are collected from known areas of natural or artificial substrates. The dry weight and ash weight are determined.
Scope and Application
The method quantifies all organic mass, autotrophic and heterotrophic, living and dead, associated with the periphyton community. Gravimetric determinations are suitable for all water.
Applicable Concentration Range
Interferences
Inorganic matter in the sample will cause erroneously large dry and ash weights. Dead periphyton and orgainc detritus that settles on the substrate will cause an overestimate of living biomass. Natural variability generally is large for biomass and may cause a problem when the method is used for comparison. When used as an index of production of the net periphyton community, grazing can result in an underestimate, and detrital settling will result in an overestimate of production.
Colonization rates vary depending on orientation of substrates (horizontal or vertical) because orientation affects the settling of organic and inorganic detritus. Vertical orientation is preferred because it decreases the settling problem.
Quality Control Requirements
No quality control requirements are available.
Sample Handling
No sample handling information is available.
Maximum Holding Time
Relative Cost
Sample Preparation Methods