Preprint volume - SIBM

Pre-print Volume – Opening keynote
M.D. BERTNESS
Department of Ecology and Evolutionary Biology, Brown University, Providence, RI, USA.
Mark_Bertness@Brown.edu
WHY EXPERIMENTAL ECOLOGY MATTERS
TO CONSERVATION BIOLOGY
PROBLEMATICHE DI ECOLOGIA SPERIMENTALE
PER LA CONSERVAZIONE BIOLOGICA
Abstract - While experimental community ecology is often portrayed as an interesting esoteric field of no
practical value, it can play a critical role informing and guiding conservation management decisions and
priorities. I argue that experimental community ecology can drive successful marine conservation using two
examples from my research: 1) How mechanistically understanding plant zonation in salt marshes provides
tools to predict and remediate human impacts on salt marshes. and 2) How challenging entrenched dogma
about the processes dictating the productivity of salt marshes reveals that we may be blind to some of the
most serious conservation threats to salt marshes and other near shore marine communities.
Key-words: eutrophication, overfishing, coastal conservation.
Introduction - Experimental community ecology and conservation biology have had
different beginnings, goals and conceptual development. Experimental community
ecology developed from an interest to conceptually and mechanistically understand the
generation of reoccurring patterns and the dynamics of natural communities (Paine,
1980). Conversely, conservation biology developed independently with the goal of
conserving and managing natural and human disturbed populations, communities and
ecosystems from further human degradation (Primack, 2008). While these fields
developed independently, they can be interdependent, but often are seen as antagonistic
rather than complimentary fields.
Here I summarize recent work in Western Atlantic salt marshes that highlights the
interdependency of experimental marine ecology and effective marine conservation
biology.
Understanding mechanisms of plant zonation - Recent research on mechanisms
generating the striking plant zonation of New England salt marshes has shown that the
zonation of pristine, nitrogen-limited marshes is dictated by competition for nitrogen
(Levine et al., 1998). This leads to the competitive dominance of plants with high
investment in belowground nutrient harvesting roots and rhizomes. Eutrophication,
driven by shoreline development and increased nutrient rich runoff, however, leads to
the competitive dominance of plants with high investment in aboveground light
harvesting leaves, a dramatic reversal of the competitive hierarchy and zonation of
these communities and the loss of most of the native community (Fig. 1; Bertness et
al., 2001). These findings lead to the simple conservation recommendation of
preserving natural woody vegetation buffers around marshes to preserve native marsh
communities.
41 st S.I.B.M. CONGRESS Rapallo (GE), 7-11 June 2010
13