Greetings,
As many of you know, there has been a recent flurry of papers (and associated letters and responses) in high profile journals discussing, among other things, eutrophication and how best to mitigate the detrimental effects of nutrient over-enrichment in aquatic systems. -Should nutrient management strategies focus only on N or P? -Should both N and P loads be reduced? -Do the current nutrient paradigms regarding freshwater and marine systems need to be re-evaluated? -Can N fixation over the long-term correct for N limitation? There is likely no simple answer to these controversial questions, but it seems timely to convene a special session to discuss these issues. On behalf of the session co-chairs (myself, Dr. Wally Fulweiler, and Dr. Roxane Maranger), we would like to invite general abstract submissions regarding these and related questions to a special session titled BO28: Can nitrogen fixation in aquatic systems reverse nitrogen limitation? to be held at the ASLO meeting in Portland, OR, on 22-26 February 2010 (www.agu.org/meetings/os10/). The full session description is attached below. Despite the session title (ASLO has strict limits on the length of the titles, so we couldnt fit everything in!), we encourage submissions related to any of the above questions and involving any aquatic system, regardless of size, salinity, or trophic status. Invited abstracts (ASLO allows only 4 with invited status, and these usually end up being oral presentations, subject to ASLO approval) will be submitted by: -Dr. Allan Devol (U. of Washington) -Dr. John Downing (Iowa State U.) -Dr. Hans Paerl (UNC Chapel Hill) -Dr. David Schindler (U. of Alberta) We anticipate a lively session and expect to receive numerous abstracts. Abstract submission is now open, and the deadline is 15 October 2009. Please feel free to contact any of the session chairs if you would like additional information on the session. We especially encourage submissions from students working on relevant topics, and please pass this announcement on to any possibly interested persons we may have missed in this mailing. We hope you will consider submitting an abstract and attending this session. Its going to be a good one! Cheers Mark, Wally, and Roxane Session chairs: Mark J. McCarthy, UQÀM & UTMSI ([email protected]) R. Wally Fulweiler, Boston University ([email protected]) Roxane Maranger, Université de Montréal ([email protected]) Session title: BO28: Can nitrogen fixation in aquatic systems reverse nitrogen limitation? The importance of nitrogen fixation in aquatic systems varies considerably, and environmental controls differ for autotrophic and heterotrophic nitrogen fixers. Traditionally, nitrogen fixation has been considered to be negligible in oligotrophic and mesotrophic lakes and most marine systems. However, new techniques for measuring nitrogen fixation are suggesting that we have underestimated the importance of N fixation in many systems. Improved methods are enabling us to construct models and scale-up ecosystem estimates. On a smaller scale, molecular techniques also are leading to new discoveries of the important players in N fixation and the environmental conditions favoring them. Coupled to these analytical breakthroughs are the recent findings that implicate climate change as an important factor contributing to reduced system productivity and a reversal of estuarine sediment function from a nitrogen sink to a source. Together, these observations have been used to question the long-standing paradigm that marine systems generally are nitrogen limited, based on the idea that, over the long-term, small amounts of nitrogen fixation will correct system nitrogen deficiencies. This session aims to review recent advances in the modeling, measurement techniques, rates, molecular attributes, environmental controls, and ecosystem-scale impacts of nitrogen fixation with a focus on the effects of climate change and the ability of nitrogen fixation to reverse nitrogen limitation in aquatic systems. Submissions are encouraged from all aquatic systems, from small streams to the open ocean. "Beyond all things is the ocean." -Seneca Robinson W. Fulweiler, Ph.D. Assistant Professor Department of Earth Sciences Boston University 675 Commonwealth Ave. Boston, MA 02215 Office Phone: 1-617-358-5466 Lab Phone: 1-617-358-5690 Cell Phone: 1-401-932-2464 Fax: 1-617-353-3290 email: [email protected] http://www.bu.edu/dbin/es/index.php/people/faculty/robinson-w-fulweiler/
