Urban streams in Puerto Rico: what can we learn from the tropics?

Abstract

AbstractUrbanization is increasing rapidly in tropical regions. Information on the response of tropical streams to urbanization is critically needed, but this information is limited. Here we summarize our current understanding of urban stream ecosystems in Puerto Rico, a tropical island with a high level of industrialization and large urban areas. We focused on 16 tributaries of the Rio Piedras watershed, which drains the San Juan metropolitan area, and 16 tributaries of the Turabo watershed, a rapidly developing suburban area. Urban effects on nutrients and aquatic macroinvertebrates were similar to those described for other geographic regions. PO4, K, and Mg concentrations increased considerably with urbanization, PO4-P ranged from 500 µg/L in heavily urbanized streams. Macroinvertebrate assemblage composition changed to dominance by tolerant taxa (e.g., snails, Chironomidae) as the proportion of urban land increased in the subwatershed. In contrast, o...