Aquatic Biota in the Sierra Nevada: Current Status and Potential Effects of AcidDeposition on Populations

摘要

The report presents the results of a field survey (Part I) and a dose-responseexperiment (Part II) conducted under Contract A-932-138. Part I describes the water chemistry, trout populations, and macroinvertebrate assemblages present in 30 representative lakes, and associated streams, in the High Sierra. Data on the water chemistry, trout populations, and macroinvertebrate assemblages of five additional lakes, including four which are included in a long-term CARB monitoring program, are also presented. Part II describes the results of a field experiment, conducted in streamside channels during snowmelt, which examined the effects of different acid levels on the survival of golden trout eggs. The experiment described in Part II concentrated on golden trout eggs because golden trout were the fish most commonly encountered during the authors' lake survey, because early life history stages of fish are the stages most susceptible to acid inputs, and because there are very few data on the vulnerability of golden trout to acid additions.