Sierra Nevada Aquatic Research Laboratory

01 Apr, 05 AM - 31 Jul, 05 AM

As the field of ecogeomorphology has grown over the past several decades, more and more case studies have shown that biological organisms can modify the biogeochemical cycles and formation of habitats that structure ecosystems. However, most studies to date have only considered a single, dominant organism. In my research, I explicitly ask whether multiple, coexisting taxa have unique impacts on the abiotic processes that structure ecosystems because of niche differences. I use a model system with caddisfly larvae to address this question. Caddisflies are insects that spend the larval portion of their life-cycle in the benthic substrate of rivers where they spin silk nets in the pore spaces between rocks to filter feed. Caddisflies can be extremely dense in nature, and previous work has shown that nets from a single species can increase river bed stability during floods. In my preliminary experiments at SNARL, I have shown that multiple, coexisting species of caddisfly partition space in the benthic substrate, leading to non-additive increases in sediment stability compared to any single caddisfly species alone. This work to date has focused on one representative grain size, 22-mm diameter grains. However, we know sediments in natural rivers are patchily distributed and can often vary greatly in their average grain size. I have developed a preliminary model of sediment transport that suggests that the effects of caddisfly nets diminish once grains are approximately 40-mm diameter. I plan to test this model with an experimental manipulation that varies caddisfly species composition and grain size simultaneously.

Visit #28160 @Sierra Nevada Aquatic Research Laboratory

Approved

Under Project # 25044 | Research

What size sediments can caddisfly nets stabilize?

graduate_student - University of California, Santa Barbara

Reservation Members(s)

Lindsey Albertson Apr 1 - Jul 31, 2012 (122 days)
Lindsey Albertson Apr 1 - Jul 31, 2012 (122 days)

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