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The differing biogeochemical and microbial signatures of glaciers and rock glaciers

Timothy S. Fegel·Jill Baron·Andrew G. Fountain·Gunnar F. Johnson·Edward K. Hall
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Abstract

Glaciers and rock glaciers supply water and bioavailable nutrients to headwater mountain lakes and streams across all regions of the American West. Here we present a comparative study of the metal, nutrient, and microbial characteristics of glacial and rock glacial influence on headwater ecosystems in three mountain ranges of the contiguous U.S.: The Cascade Mountains, Rocky Mountains, and Sierra Nevada. Several meltwater characteristics (water temperature, conductivity, pH, heavy metals, nutrients, complexity of dissolved organic matter (DOM), and bacterial richness and diversity) differed significantly between glacier and rock glacier meltwaters, while other characteristics (Ca 2+ , Fe 3+ , SiO 2 concentrations, reactive nitrogen, and microbial processing of DOM) showed distinct trends between mountain ranges regardless of meltwater source. Some characteristics were affected both by glacier type and mountain range (e.g. temperature, ammonium (NH 4 + ) and nitrate (NO 3 - ) concentrations, bacterial diversity). Due to the ubiquity of rock glaciers and the accelerating loss of the low latitude glaciers our results point to the important and changing influence that these frozen features place on headwater ecosystems.

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Journal of Geophysical Research G: BiogeosciencesArticle
90° N90° S · 180° W ← longitude → 180° E
Source-reported bounding extent: 34.08906131584996° to 49.03786794532644° latitude; -124.8046875° to -105.46875° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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BibTeXRIS

Timothy S. Fegel, Jill Baron, Andrew G. Fountain, Gunnar F. Johnson, Edward K. Hall. 2016-03-29. The differing biogeochemical and microbial signatures of glaciers and rock glaciers. https://doi.org/10.1002/2015jg003236

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