Agenda 2000, rebalancing, oilseed rape, mixed-integer programming model, crop rotation
评估当前市场条件和2000年议程共同农业政策改革（特别是谷物与油籽支持再平衡）对英格兰东部三种代表性农场油菜籽种植面积的影响，发现常规轮作下面积大幅减少，但双休耕作物轮作下面积保持改革前水平。
This paper assesses the impact of current market conditions and Agenda 2000 CAP reforms, particularly the 'rebalancing' of support between cereals and oilseed crops, on crop gross margins and hence on the incentive to produce oilseed rape on three representative farm types in eastern England. Results indicate that under a conventional rotation, oilseed rape area falls substantially on two of the farm types considered. However, the incentive to plant break crops more frequently increases after the reform; under a two-break crop rotation, oilseed rape area remains at pre-reform levels. Oilseed rape prices of c. £100 per tonne, particularly when combined with unrestricted set-aside rates, conventional rotations and low cereal prices, would give farmers in eastern England substantial incentives to reduce the area of the crop grown.