A flow-proportional sampler for plot and lysimeter studies

Holdsworth, P.M.; Roberts, G.

doi:10.1016/0022-1694(82)90157-3

Cited by 4 publications

(1 citation statement)

References 2 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…An ISCO automatic sampler collected 500 ml sample volume for each time that the reservoir filled. Flow proportional sampling schemes have been applied under various situations (Fredrikson, 1969;Keffer, 1975;Holdsworth and Roberts, 1982;Cuttle and Mason, 1988;Tremwell et al, 1991;Braskerud et al, 2000). Oanh and Bengtsson (1997) presented cost effective sampling studies for industrial effluent, indicating that a grab sample is sufficient (systematic error less than or equal to 13) when flow variation is less than or equal to 120 percent and concentration variations are less than or equal to 10 percent of the mean.…”

Section: Jawra 1198mentioning

confidence: 99%

WATER QUALITY SAMPLING SCHEMES FOR VARIABLE FLOW CANALS AT REMOTE SITES¹

Abtew¹,

Powell

2004

J American Water Resour Assoc

View full text Add to dashboard Cite

Growing interest in water quality has resulted in the development of monitoring networks and intensive sampling for various constituents. Common purposes are regulatory, source and sink understanding, and trend observations. Water quality monitoring involves monitoring system design; sampling site instrumentation; and sampling, analysis, quality control, and assurance. Sampling is a process to gather information with the least cost and least error. Various water quality sampling schemes have been applied for different sampling objectives and time frames. In this study, a flow proportional composite sampling scheme is applied to variable flow remote canals where the flow rate is not known a priori. In this scheme, historical weekly flow data are analyzed to develop high flow and low flow sampling trigger volumes for auto‐samplers. The median flow is used to estimate low flow sampling trigger volume and the five percent exceedence probability flow is used for high flow sampling trigger volume. A computer simulation of high resolution sampling is used to demonstrate the comparative bias in load estimation and operational cost among four sampling schemes. Weekly flow proportional composite auto‐sampling resulted in the least bias in load estimation with competitive operational cost compared to daily grab, weekly grab sampling and time proportional auto‐sampling.

show abstract