Topographic wetness guided dairy manure applications to reduce stream nutrient loads in Central New York, USA

We observed that application of manure to drier pastures results in less TDP and NOX surface losses, but an undesirable increase soil TDP accumulation. Further, pastures receiving dairy manure are typically N limited during summer months, limiting plant P uptake. Manure N amendment reduced TDP accumulation and increases crop yield, but slightly increased NOX surface losses. Spreading dairy manure based on the TI concept represents a feasible path towards reduction of agricultural non-point nutrient runoff, although management strategies need to consider ways to also reduce the long-term accumulation of soil P, which could have consequences in the future that are difficult to mitigate.