The devil is the detail: finding meaning indicators of nutrient management on organic and low-input farms

Summary

In low-input and organic systems, nutrient management is key to ensuring the short-term productivity and the longer-term sustainability of the farming system. Farm-gate nutrient budgets/balances calculate the inputs of nutrients to, and outputs from a system. Hence, they can be used to assess the nutrient use efficiency. Nutrient balances of 69 organic and low-input dairy farms in seven European countries were carried out using a sustainability assessment tool. The tool assesses each individual farm against a number of indicators. Part of the assessment of nutrient management is the calculation of an N,P,K budget, based on physical inputs and outputs for each enterprise. The results show considerable variation in the calculated N,P,K balances. The paper will explore the reasons for high nutrient surpluses and deficits and discuss the advantages and disadvantages of calculated farm-gate nutrient budgets.