Community organization and ecosystem response to anthropogenic impacts: Are subtropical, coastal rivers different?

Background/Question/Methods

Streams in human-developed landscapes typically have altered ecosystem structure and function including high nutrient and toxicant concentrations, low oxygen, significantly altered food webs and overall diminished ecosystem function. Our ability to manage these urban and urbanizing streams to minimize ecosystem alteration is inhibited by a lack of understanding of the mechanisms of degradation, and by the global variability in urban and ecosystem characteristics.

Results/Conclusions

We summarize the important characteristics of coastal, urban river systems from S. Florida and Puerto Rico in light of sustainability and resilience theory as a mechanism for managing and restoring these important ecosystems so heavily relied upon by human populations.  Significant changes in the fresh-salt water interface, sagging oxygen levels and continual invasion of novel species represent significant challenges to coastal stream restoration in urban systems.  New endocrine disruptors are now present in alarming levels.  We also present information on how the isotopic signatures have been altered as well as the overall food webs.