Trophic structure and the role of predation in shaping hot desert communities

摘要: Low precipitation and high temperatures in deserts limit primary productivity, reduce rates of herbivory microbial decomposition. As a result, the small amount plant tissue produced dies unconsumed turns to litter that is consumed by macrodetritivorous arthropods, which are preyed upon ectothermic arthropods reptiles. This ectotherm-based food chain energetically efficient and, despite low productivity desert habitat, able support fourth trophic level endothermic predators, i.e. mammals birds, forage over large areas locate their prey visually from distance. four-link results interactions run predators through ones macrodetritivores. Thus, macrodetritivores released predation become food-limited. However, full expression these occurs only habitats with cover. In productive habitats, cover blocks vision provides refuge ones. becoming abundant controlling prey, increase decreases energy reaches top as it has mainly structural effect: mediate interactions.