Prediction of the Response of Pond Biota to Animal Waste Fertilization

摘要

This study examined the production and water quality response of non-flowing ponds fertilized with anaerobically digested dairy manure at three fertilization rates: 5,500, 16,400, and 36,900 kg ha -1 yr -1 (wet weight). Primary productivity, the concentration of solids and fish yield (Micropterus salmoides and Notemigonus crysoleucas) were monitored in addition to N and P concentrations and fluxes. Primary productivity was increased by the manure inputs. Microbial biomass supported by the organic substrates in the manure inputs contributed 17% of the total fixed carbon in these experiments. Calculations of N and P flux revealed that P limits production in the unfertilized ponds and in the low-rate ponds but not in the moderate and high rate ponds. The upper limits on pond fertilization rates are determined by water quality degradation from high ammonia concentrations which can be predicted as a function of manure load; thus, the upper limits on permissible manure inputs can be calculated.