There are no special field sampling concerns associated with these parameters other than those described in the section on basic sample collection techniques. It is especially important for these parameters that the sample is collected from undisturbed water. Once you step into a stream, you stir up the stream bottom thats why you step upstream, lean, and reach into the current for the sample. In lakes, boat propeller action also may disrupt sediments in shallow areas. Again, do not sample from disrupted water.
TSS (mg/L) = ([A-B]*1000)/C
Where A = End weight of the filter
B = Initial weight of the filter
C = Volume of water filtered
Turbidity is a measurement of the optical property of water a measure of the amount of light that is scattered and absorbed by particles in the sample. It is a simple measurement that requires the use of either a nephelometer or Jackson turbidimeter to compare a reference solution to the sample. Turbidity measurement does not require any sample preparation, other than shaking the sample bottle well before analysis. The sample is simply poured into a glass tube, placed inside the instrument with a reference solution and the result is read directly from the instrument. (The nephelometer has recently become recognized as the more accurate and recommended piece of equipment for this analysis. However, if a Jackson turbidimeter is what you have available, it will work fine.)
TSS and turbidity samples should be held in the dark on ice or at 4o C. In this condition, TSS Samples can be held for up to 7 days and turbidity samples for up to 2 days.
Randomly select 5 to 10 percent of the samples and collect lab replicates for them. Lab QA/QC will involve selecting duplicate analysis, and calibration of all equipment used.
The next section discusses chlorophyll a measurement in lakes.
Measuring Temperature | Measuring Dissolved Oxygen | Measuring pH | Measuring Secchi Disk Depth | Measuring Nutrient Concentrations | Measuring TSS | Measuring Chlorophyll a | Measuring Fecal Bacteria
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