Estimating Total Suspended Sediment Yield With Probability Sampling
نویسنده
چکیده
The "Selection At List Time" (SALT) scheme controls sampling of concentration for estimating total suspended sediment yield. The probability of taking a sample is proportional to its estimated contribution to total suspended sediment discharge. This procedure gives unbiased estimates of total suspended sediment yield and the variance of the estimate while automatically emphasizing sampling at higher flows. When applied to real data with known yield, the SALT method underestimated total suspended sediment yield by less than 1%, whereas estimates by the flow duration sediment rating curve method averaged about 51 % underestimation. Implementing the SALT scheme requires obtaining samples with a pumping sampler, stage sensing device, and small battery-powered computer.
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