| Summary: |
The stocks and flows of nitrogen (N) and phosphorus (P) were quantified for five case studies, representing contrasting agricultural systems in China and the UK. The input of nutrients exceeded the output of nutrients in agricultural products for all five systems, although to varying degrees between individual case studies.Excessive input of nutrients for each system increases the risk of negative environmental impacts on soil, air and water quality. Soils accumulate nutrient stocks due to excessive nutrient inputs, representing an under-exploited nutrient reserve that could contribute to future agriculture production. Livestock and crop production are increasingly disconnected in China. Manure application was limited to high-value fruit and vegetable crops in the systems analysed, but often without adequate accounting for the nutrient content of the applied manure.Pathways to improve the efficiency of nutrient use are identified. |
