In 1974 the U.S. Geological Survey entered into a cooperative agreement with the California Department of Water Resources to study the limnology of Fallen Leaf Lake and adjacent streams. The lake is in California, near the crest of the Sierra Nevada about 23 miles southwest of Reno, Nevada (fig. 1). The study was undertaken to help develop a better understanding of selected characteristics of a high-altitude dilute-solution lake-stream system and the effect of man on the system. Fallen Leaf Lake and the adjacent streams were chosen for the study because the lake represents an alpine system in a basin that has had limited development for a number of years. Recently, local and state groups have become extremely interested in the effects of man's activities on the condition of the lake.
The study was designed to:
1. Provide data on selected physical, chemical, and biological characteristics of Fallen Leaf Lake and adjacent streams,
2. Determine whether the magnitude and changes in magnitude of a number of physical, chemical, and biological variables are affected by natural or cultural processes,
3. Characterize a high-altitude, dilute-solution aquatic ecosystem,
4. Compare and contrast the physical, chemical, and biological characteristics of Fallen Leaf Lake and adjacent streams with other lakes in the area.
