Effects of Animal Husbandry on Secondary Production and Trophic Efficiency at a Regional Scale

摘要: Agricultural systems are expected to have higher net secondary production (NSP) than natural as a result of trophic efficiency and lower interannual variability. These differences, however, not been quantified across regional gradients. We compiled dataset herbivore biomass, consumption, NSP, annual precipitation, aboveground primary (ANPP) for extensive livestock farms wide precipitation gradient in Argentina. compared these data with worldwide published studies systems. In double-logarithmic scale, NSP agricultural increased ANPP from semiarid subhumid decreased humid systems, response that contrasted the linear positive increase Compared dominated by homeotherms, E troph (NSP:ANPP) areas was 8 times higher, due 2 consump (Consumption:ANPP) 4 prod (NSP:Consumption). areas, 46 13.7 3.3 prod. 5 2.5 The variation major determinant 60 % decoupled variability precipitation. reach (1) diverting proportion detritus grazing chain, (2) converting more efficiently consumption into (3) stabilizing biomass years.