Evaluation of N environmental risks on Andosols from an intensive dairy farming watershed using DNDC

摘要: Abstract Manure nitrogen (N) in the livestock sector has become a key driver of environmental change. The denitrification–decomposition (DNDC) model was used to evaluate N pollution strengths on Andosols with intensive dairy manure application Upper Naka River Watershed, Japan. calibrated capable predicting Andosol flows because simulated soil mineral content, oxide (N 2 O) fluxes, denitrification rate, and crop uptake matched patterns magnitudes field observations from wide range textures, as well management cropping systems. simulations showed that current systems caused low use efficiency large amount NO 3 − -N leaching O emission. 27%–42% 37%–55% input for uplands paddy rice, respectively. much more serious risks 123–362 kg N ha − 1  yr emissions 6.53–11.8 kg N ha than lowland rice 17.4–103 kg N ha 0.59–2.77 kg N ha . Forage rice/barley have high cleaning capability due greater which reached 304 kg N ha High precipitation stimulated leaching. Sandy also higher unsuitable rice. Slurry emission compost manure. To mitigate pollution, critical rate recommended be approximately 380, 470, 640, 390 kg N ha loam sand planted maize/grass, forage rice/barley, rice/fallow winter application,