An Analysis of Eco-Efficiency Scenarios in Dairy Farming: Simulations of Milk Production

Abstract

Farming eco-efficiency requires the approach of economic efficiency, as well as the impact upon the environment. The analysis of eco-economic efficiency of a dairy farm was done by simulating different levels of milk production. The study starts from the real situation of a farm in which the crops and forage basis, productions, rations, the cost and income were quantified and the nutrient balances P, N and K, as well as the profit value were calculated. By simulating with ±25% the peak milk production, 4 scenarios were enacted with the use of the N-CyCLE software: the minimization of P, N and K balances, respectively the profit maximization. The increase of milk production correlates positively with the profit (r=+0.935 on p<0.001) and also with the nitrogen balance (r=+0.471 on p<0.05). The four scenarios significantly influence the value of profit – the scenario towards maximizing the gross margin generates the highest profit (896.5 euro/cow), and the scenario towards nitrogen minimum balance generates the lowest profit (503.08 euro/cow). The eco-economic character of the farm was obtained using barycentric coordinates of ½ weights from the values of N’s scenario at the gross margin rates with the computer algebra software Maple13. The optimization of milk production through gross margin maximization and the nitrogen minimization allows expressing the eco-economic character; in this case, at a peak production of 40 kg/day, the farm acquires an eco-economic character when the nitrogen balance is 91.5 kg N/ha/year and the profit is 769 euro/cow.