Diatoms of North AmericaUse of monitoring data to inform paleolimnological records, examples from two lakes in northern California
Description: Paleolimnological proxies serve as a valuable means of providing past
lake environmental records that span well beyond the period of historic
measurement and monitoring. In the case of diatoms, relative abundance
counts are standard practice, and down core changes are interpreted
through recognition of biozones, multivariate statistical methods and
inference models from known biological data, experimentation, and
training sets. Limitations on our interpretations are based on lake
sensitivity, and our understanding of the complex interplay of
forcings on that diatom community. Limitations are also based on the
quality and resolution of age models and the muting of seasonal and
annual signals through the lens of multi-annual averaging and
sedimentary processes. What part of the signal is lost, even in lakes
with “good” age models, and what aspects of monitoring and sampling can
best inform us in making paleolimnological interpretations? Examples are
explored from core records in both Fallen Leaf lake, Lake Tahoe Basin,
and Castle Lake, Siskiyou Mountains of northern California, where
multi-year limnological sampling and monitoring datasets exist.
Target audience: Water managers,
policymakers, researchers, and others interested in applying regional
diatom data to publicly available tools for assessing biotic integrity.
