The effect of ‘Double High Agriculture’ on nitrogen losses from crop production to coastal water in China

‘Double High Agricultural’ (DHA) is a nutrient management strategy focusing on increasing nitrogen (N) and phosphorus (P) use efficiencies, while also increasing crop yields. DHA may thus reduce losses of nutrients to the environment. We quantified the impact of DHA on N inputs to rivers and coastal seas in the year 2050. To this end, we applied the Global NEWS (Nutrient Export from WaterSheds) model. Two scenarios were developed based on two different agricultural practice of DHA: 1) The Integrated Soil-crop Systems Management (ISSM) scenario which assumes a 30% lower synthetic fertilizer application and 30% higher crop yields; 2) The ISSM-MR scenario, which is as ISSM, but assumes increased Manure Recycling in crop production, leading to lower synthetic fertilizer use. The results indicate that river export of dissolved inorganic N (DIN) and dissolved organic N (DON) in the ISSM scenario are about 10% lower than in the reference scenario. In ISSM-MR river export of DIN is about 30% lower than in the reference scenario.