Fish Communities and Conservation of Aquatic Landscapes in Northeastern Mesoamerica.

摘要: Fish assemblages at the reach scale within a river network are structured relative to local abiotic factors that are, in turn, constrained larger scales of valley segment or catchment. While important fish well understood, studies constraints have yielded variable conclusions, spurring need for further new settings and biogeographic contexts. This study investigated importance catchmentand reach-scale variation assemblage composition rivers northeastern Mesoamerica. I assembled catchment environment, datasets 72 sampling sites on main stem 12 16 major watersheds draining coast Belize. Partial canonical correspondence analysis was used determine unique effects reach-level descriptors presence absence, abundance, community summary metrics. Results showed that, combined, variables explained large portion total data (57 73%), environment greater (24 26%) than (9 20%). Variables representing landscape position (local elevation, watershed area) its correlates (channel width, depth variation, substrate composition) related most strongly data. The results suggest landscape-scale stronger influence environmental conditions scale. These contrast with past findings, biodiversity conservation efforts must aim protect ecological integrity across positional gradient from mountains sea, is biologically meaningful planning coordination begin