Impact of introduced carp (Cyprinus carpio)in subtropical shallow ponds in Central Mexico

摘要: In Mexico, as in many other subtropical and tropical countries, there has been a recent trend towards stocking non-native carp (Cyprinus carpio) lakes ponds source of food rural areas. However, the results study series small(1–8 ha.), shallow (<2 m), semi-natural Acambay, high altitude valley basin Lerma river volcanic belt central west illustrate that over threshold value may have detrimental ecological impact at several trophic levels. Ponds with tended to be turbid levels suspended solids, few rooted macrophytes epibenthic invertebrates. contrast, without had clear water abundant associated invertebrates, particularly gastropod molluscs. The direct uprooting by benthic foraging appeared most important mechanism switching from macrophyte-dominated state. thus appear confirm alternative stable-state hypothesis developed intemperate lakes, although importance rather than pelagic interactions was emphasised. implications for native fauna intrinsic conservation supply local people are outlined.