Calibrating SALT: a sampling scheme to improve estimates of suspended sediment yield
نویسنده
چکیده
SALT (Selection At List Time) is a variable probability sampling scheme that provides unbiased estimates of suspended sediment yield and its variance. SALT performs better than standard schemes which are estimate variance. Sampling probabilities are based on a sediment rating function which promotes greater sampling intensity during periods of high sediment yield. When preparing to monitor using SALT, the quality of the existing suspended sediment rating data is an important consideration. SALT variance, based on an intensive data set from a river in northwestern California, showed greater sensitivity to the SALT sample size than to the quality of the calibration set.
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