Beginning the 2010-2011 season, we have installed a telemetry network that utilizes the Iridium satellite network and radios to connect 14 meteorological stations, 8 stream gages, and five lake monitoring stations to transfer data year round. Four hubs, often co-located at a monitoring site when topography allows, receive satellite phone calls originating in the US to open a connection, then sequence through as many as seventeen different data loggers via radio communications to harvest the latest data.
Microbial mats in Dry Valley streams persist through winter and are revived with summer streamflow (Fig. 1A). Tyler Kohler, PhD student, evaluated controls on mat biomass of 3 mat types (orange, black, and green) to changing hydrology over 20 years by creating smoothed trends from generalized additive mixed models (Fig. 1B) and comparing trends with Pearson Correlation Coefficients. Mat biomass collectively decreased during the middle of the record coinciding with a period of low flows and a “flood” summer (Fig. 1C).
Over the past decade, we have developed a conceptual model that documents the connectivity of glaciers (primary source of water) to lakes on the valley floor via stream channels. The stream channels provide two important functions beyond conveyance of water and associated solutes and energy to lakes – (1) they provide habitat for algal mats that include diatom and microbial communities, and (2) they accommodate active exchange of water between the channel and the hyporheic zone underneath and adjacent to the channel.
Wormherder creek is an ephemeral stream that occurs only during high flow. Located near Lake Bonney in Taylor Valley, in most years this hillside is bone-dry, making it an ideal site to investigate the long-term effects of extreme pulse/press events. The insert (left) shows an experiment that was flooded during the high flow of 2001-02 and 2008-09. We hypothesized that climate driven increases in the frequency and magnitude of high-flow events will lead to increased connectivity and subsequent redistribution of nutrients and biota across the landscape.