Nutrient cycling on dairy farms in the Netherlands: The role of farm structure, management and trade-offs

Abstract

Food production is a major driver for crossing planetary boundaries. Improving nutrient cycling may enable maintaining production while reducing environmental losses. This study assesses the current state of Dutch dairy on-farm nutrient (nitrogen- N, phosphorus - P) cycling through re-use of manure, scope for improvement and potential trade-offs. Data of 27 farms between 2006–2022 were used.Nutrient use efficiency (Output/Input) varied widely, with an average of 0.39 (0.29–0.47) for N and 0.88 (0.69–1.01) for P. Combining circularity and efficiency indicators showed that most gain in efficiency could be made by increasing cycled flow. Management related with improved cycling had lower external nutrient inputs, both from fertiliser and feed. Farm structure mattered for farm performance, as extensive farms with lower external N inputs from fertiliser or feed had higher N cycling and lower greenhouse gas emissions, but at the costs of agricultural land use and productivity.