摘要
通过把全面的农田试验和矿质风化释放养分以及微量元素循环具体研究结合起来,用一个系统分析方法来评价农场尺度上的养分和微量元素可持续性。为了比较有机和常规农业管理方式,在瑞典北部的jebyn奶牛场进行了一个包括磷、钾和锌在内的农场尺度上的实例研究。通过结合不同的元素平衡法(农场总体尺度、畜舍尺度和农田尺度)以及进一步把这些方法应用到FARMFLOW模型,我们能够把子系统内质量流和库结合起来并建立子系统之间联系,来进行农场尺度上的预测。研究发现农场内部的元素流动大,而且农场有内部源(锌)和损失项(钾)。在(O|¨)jebyn奶牛场形成并得到验证的方法是很有前途的,认为可以应用到任何农场。
A systems analysis approach was used to assess farm-scale nutrient and trace element sustainability by combining full-scale field experiments with specific studies of nutrient release from mineral weathering and trace-element cycling.At the jebyn dairy farm in northern Sweden,a farm-scale case study including phosphorus (P),potassium (K),and zinc (Zn) was run to compare organic and conventional agricultural management practices.By combining different element-balance approaches (at farm-gate,barn,and field scales) and further adapting these to the FARMFLOW model,we were able to combine mass flows and pools within the subsystems and establish links between subsystems in order to make farm-scale predictions. It was found that internal element flows on the farm are large and that there are farm internal sources (Zn) and loss terms (K).The approaches developed and tested at the jebyn farm are promising and considered generally adaptable to any farm.
