Assessment of environmental effects, animal welfare and milk quality among organic dairy farms.

摘要

Within the organic dairy farming sector in Germany, traditional mixed farms with relatively low yearly milk yields of around 6000 kg per cow exist beside highly specialised grassland based farms with more than 9000 kg milk yield per cow and year. Specialisation and intensification are discussed critically within the organic sector as negative environmental effects are expected. In this study the potential environmental impacts of four different types of organic dairy farms are compared, based on a survey of 27 organic dairy farms classified by a percentage of grassland on total farm area and feeding intensity. The analysed environmental impact categories were energy consumption, climate impact, land demand, ammonia emissions, nitrate leaching, conservation of soil fertility, biodiversity, animal welfare and milk quality. Farms with a high feeding intensity tended to show ecological advantages in the impact categories climate impact and land demand. In contrast, low-input farm types showed positive environmental effects in the impact categories animal welfare, milk quality and ammonia losses. In an overall environmental index, the farm type 'low-input mixed farming' showed the best results. The hypothesis that farms orientated on the traditional principles of organic farming tend to have less negative environmental effects even within the range of organic dairy farms is hereby confirmed. However, further research is needed to affirm the methodology used to quantify the environmental effects in the categories of animal welfare and milk quality. The results show that focussing only on the classical environmental impact categories, e.g. energy consumption and climate impact, may lead to different results than a more complex system approach that considers a broader range of relevant impacts and ecological benefits