Maryland Synoptic Stream Chemistry Survey: Estimating the Number and Distribution of Streams Affected by or at Risk from Acidification

摘要

The survey was designed to provide statewide estimates of the number and extent of stream resources presently affected by or at risk from acidification. Streams surveyed were selected as a stratified random sample from a statewide list of non-tidal stream reaches. The sample represented water quality conditions in a population of interest comprising the state's headwater stream resources sampled during relatively constant phenological conditions during the spring of 1987. Of the 6875 non-tidal stream reaches in the state, an estimated 5411 stream reaches belong to the population of interest. Volunteers collected water samples from 559 randomly selected and 71 special interest reaches statewide. Samples were analyzed for acid neutralizing capacity (ANC), pH, conductivity, dissolved organic carbon (DOC), color, and dissolved inorganic carbon (DIC), using analytical methods developed for the EPA National Surface Water Survey.