<div>Hello, </div><div><br></div><div>this week's Colloquium speaker is John Sabo from Arizona State University, currently on sabbatical at NCEAS. His research is mainly focused on freshwater ecology and ecological modelling. His recent papers have explored the effect of disturbance on community ecology. Please let me know if you are interested in meeting with him on Thursday, we still have some openings. If interested please send me your hours of availability.</div>
<div><br></div><div>Thanks!</div><div><br></div><div>Mauricio</div><div><br></div><div>PD. See below a summary of his Thursday's talk, his bio, and links to his research. </div><div><br></div><div><p style="margin: 0.0px 0.0px 0.0px 0.0px; font: 12.0px 'Lucida Grande'">
<span style="letter-spacing: 0.0px"><b><span class="Apple-style-span" style="font-size: small;">Title</span></b><span class="Apple-style-span" style="font-size: small;">: Floods, droughts and the scaling of food chain length with drainage area in rivers </span></span></p>
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<p style="margin: 0.0px 0.0px 0.0px 0.0px; font: 12.0px 'Lucida Grande'"><span style="letter-spacing: 0.0px"><b><span class="Apple-style-span" style="font-size: small;">Summary: </span></b></span></p>
<p style="margin: 0.0px 0.0px 0.0px 0.0px; font: 10.0px 'Lucida Grande'"><span style="letter-spacing: 0.0px"><span class="Apple-style-span" style="font-size: small;">Floods, droughts and other extreme hydrologic events play key roles in coupling human and natural systems. Floods can cause tremendous damage and mortality and cripple local economies. By contrast, floods are critical to freshwater fisheries, some of which supply the majority of the protein to people in developing nations. Prolonged droughts and human dewatering of rivers for municipal, industrial and agricultural uses pit farmers against fisherman for limiting water resources forcing us to ask tough questions like: "Which rivers (and their fisheries) are we willing to let run dry in order to put produce on the table?" Or, "How will fish, and the food webs that support them, respond to prolonged or intensified extreme events?" Food chain length (FCL) is a fundamental component of food web structure, and large fish--often at the top of aquatic food chains--are the pièce de résistance across the world. In this talk I will describe the results from my recent work documenting how floods and droughts impact FCL in river ecosystems of North America. Studies in a variety of ecosystems suggest that FCL is determined by energy supply, environmental stability, and/or ecosystem size. However, the nature of the relationship between environmental stability and FCL, and the mechanism linking ecosystem size to FCL, remain unclear. In rivers FCL increases with drainage area and decreases with hydrologic variability (floods) and intermittency (severe drought). Both floods and droughts appear to shorten river food chains but do so in different ways. Droughts eliminate top predators whereas floods take out the middle men in food webs forcing top predators to forage lower on the food chain. Hence, the effects of droughts are more severe and appear to be more long lasting. The dewatering of rivers nationwide and globally is having measureable effects on fisheries in freshwater and in coastal ecosystems. These effects will intensify in California until we adopt a 7-state, regional water conservation plan aimed at reducing surface and groundwater withdrawals by 16-34% before the next population doubling in the region.</span></span></p>
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<p style="margin: 0.0px 0.0px 0.0px 0.0px; font: 10.0px 'Lucida Grande'"><span style="letter-spacing: 0.0px"><b><span class="Apple-style-span" style="font-size: small;">Short Bio: </span></b></span></p>
<p style="margin: 0.0px 0.0px 0.0px 0.0px; font: 10.0px 'Lucida Grande'"><span style="letter-spacing: 0.0px"><span class="Apple-style-span" style="font-size: small;">Dr. Sabo is an aquatic ecologist interested in using insights from the fields of hydrology and geomorphology to understand the ecology of rivers. He has worked on rivers in coastal Washington, California and most recently the Colorado River and its tributaries. Dr. Sabo is broadly interested in articulating regional scale solutions to problems in freshwater sustainability. Dr. Sabo received a Masters degree in Fisheries from the University of Washington and a Ph.D. in Ecology from UC Berkeley. He spent 1 year as an NRC postdoc at the National Marine Fisheries Service developing and refining risk assessment methods for endangered species. He joined the faculty at Arizona State University in 2001, where he is an Associate Professor in the School of Life Sciences. Dr. Sabo’s research in Arizona focuses on the role of water (as a resource and source of disturbance) in determining community structure in stream and riparian ecosystems. This work is funded by the National Science Foundation, the US Geological Survey and the US Department of Defense. Currently, Dr. Sabo is a visiting professor in Ecology, Evolution and Marine Biology at UCSB. </span></span></p>
<p style="margin: 0.0px 0.0px 10.0px 0.0px; font: 10.0px 'Lucida Grande'; min-height: 12.0px"><span class="Apple-style-span" style="font-size: small;"><span style="letter-spacing: 0.0px"></span><br></span></p>
<p style="margin: 0.0px 0.0px 10.0px 0.0px; font: 10.0px 'Lucida Grande'"><span style="letter-spacing: 0.0px"><b><span class="Apple-style-span" style="font-size: small;">Links:</span></b></span></p>
<p style="margin: 0.0px 0.0px 10.0px 0.0px; font: 10.0px 'Lucida Grande'"><span class="Apple-style-span" style="font-size: small; "><a href="http://www.public.asu.edu/~jlsabo/">http://www.public.asu.edu/~jlsabo/</a></span></p>
<p style="margin: 0.0px 0.0px 10.0px 0.0px; font: 10.0px 'Lucida Grande'"><span style="letter-spacing: 0.0px"><span class="Apple-style-span" style="font-size: small;"><a href="http://www.sciencemag.org/content/330/6006/965.abstract">http://www.sciencemag.org/content/330/6006/965.abstract</a></span></span></p>
</div><div><span style="letter-spacing: 0.0px"><br></span></div><div><br></div><br clear="all">Mauricio<br><br>=================================<br>Mauricio Torres-Mejia<br>PhD Candidate<br>Department of Biology<br>University of California, Riverside, CA, 92521<br>
USA<br><a href="http://student.ucr.edu/~rtorr006/">http://student.ucr.edu/~rtorr006/</a><br><br>