Spatial and temporal distribution of dissolved oxygen in Crater Lake,Oregon

Abstract

Small temporal and spatial variations in the distribution of dissolved oxygen in Crater Lake, Oregon, are used to estimate the mean age of the lake’s deep water, the flux of labile organic carbon to the deep lake, and the influence of hydrothermal activity on the concentration of dissolved oxygen within the lake. An increase in the concentration of dissolved oxygen in the deep water during winter 1988–1989 indicates that 30–45% of deep water was replaced with well‐oxygenated surface water. This deep‐water renewal corresponds to a mean deep water residence time of 2–4 yr. The deep‐water oxygen consumption rate is 21–26 µmol m−3 d−1, which occurs primarily through the oxidation of organic matter and, to a lesser extent, the oxidation of reduced inorganic species that are introduced to the lake via subsurface hydrothermal springs.