URBAN STREAMS IN PUERTO RICO: EFFECT OF CHANNELIZATION ON HABITAT CONDITION AND DIVERSITY OF AQUATIC MACROINVERTEBRATES
Channelization is a common form of stream degradation in urban areas that negatively affects ecosystem function and diversity. In Puerto Rico, stream channelization is a common occurrence in urban areas, often in response to flooding. However, we know little about their impact. The objective of our study was to assess habitat condition in channelized sections and how that condition translates into impacts on the diversity of aquatic macroinvertebrates. We characterized three channel types in the Río Piedras Watershed, San Juan, Puerto Rico: 1) complete concrete channelization, 2) intermediate channelization, mostly channelized section that became degraded and have heterogeneous benthic substrate; and 3) reference channels without channelization. At each site we assessed stream condition using the Stream Visual Assessment Protocol (SVAP-PR), Family Biotic (FBI-PR) and BMWP-PR. The three channel types were significantly different among themselves and formed a gradient of degradation. Channelized sites were classified as impaired and had the lowest biodiversity. In contrast, natural channels were in good conditions and supported high diversity. Overall, channelization negatively affects stream ecosystems eliminating habitats, reducing riparian zones, and supporting reduced biodiversity. However, deterioration of channelized section recover their diversity.
Natalia Rodriguez-Ortiz (Primary Presenter/Author), University of Puerto Rico-Río Piedras Campus, firstname.lastname@example.org;
Alonso Ramirez (Co-Presenter/Co-Author), University of Puerto Rico, Rio Piedras, email@example.com;