Grain legumes have declined to a low base in many regions of intensified agriculture yet have the potential both to safeguard food security and satisfy rising ethical demands from food consumers. Here, the scope for legume expansion is examined in a long‐established agricultural region in eastern Scotland where grain legumes declined to <0.3% of cropped area in the 1930s and now vary around 1%. Data from the EU's Integrated Administrative and Control System (IACS) were combined with national agricultural survey to resolve uncertainties over possible restrictions to expansion following 20th‐century intensification. The grain legumes, peas and beans for animal and human consumption, were found to occupy six crop‐grass systems covering a wide range of agronomic input and geographical location. The phase of agricultural intensification between 1950 and 1990 had widened rather than restricted the systems in which they occur and could expand. Moreover, the diversity of the crop‐grass systems provides scope for complementary expansion of several products such as beans for aquaculture, pulses for human consumption, and peas for stockfeed without diminishing the areas of the most profitable crops. Among crop systems, N inputs following 20% legume inclusion would fall from the current 178 to 140 kg/ha (78.6%) at the high‐input end of the range and from 92 to 71 kg/ha (77.0%) at the low‐input end. Further reductions to 50%–60% of the existing N input to intensive crop sequences were estimated assuming a residual fixed nitrogen of 50–75 kg/ha and legume inclusion of 33%. Legume expansion would also bring a range of environmental benefits across all crop‐grass systems. While analysis using IACS brought many insights, major limitations to estimating national N‐balances were identified in lack of data on residual N following legumes, in imported animal feed and in the contribution of forage legumes to grassland.

中文翻译：

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向农田中更多的豆科植物包容过渡：确定氮肥经济的机会并估算其效益

在许多集约化农业地区，豆类作物基数较低，但既有可能维护粮食安全，又有可能满足粮食消费者日益增长的道德要求。在这里，对苏格兰东部一个历史悠久的农业地区的豆科植物扩张范围进行了研究，那里的豆类谷物在1930年代下降到种植面积的<0.3％，现在变化约1％。欧盟综合行政与控制系统（IACS）的数据与全国农业调查相结合，以解决20世纪集约化之后可能限制扩张的不确定性。发现用于动物和人类消费的豆类，豌豆和豆类谷物占据了六个作物草系统，涵盖了广泛的农业投入和地理位置。1950年至1990年间的农业集约化阶段扩大了而不是限制了其发生并可能扩展的系统。此外，农作物-草种系统的多样性为扩大一些产品（例如用于水产养殖的豆类，用于人类消费的豆类和用于饲料的豌豆）的互补性扩展提供了空间，而同时又不会减少最有利可图的农作物的面积。在农作物系统中，豆科植物含量为20％后的氮输入将从该范围的高输入端的当前178降至140千克/公顷（78.6％），而低端则从92降至71千克/公顷（77.0％）。输入端。假设剩余固定氮为50-75 kg / ha，豆类含量为33％，则估计精耕细作序列中现有氮素输入量将进一步减少至50％–60％。豆科植物的扩大还将为所有农作物草种系统带来一系列环境效益。尽管使用IACS进行分析带来了许多见识，但由于缺乏有关豆类残留的N数据，进口动物饲料和饲用豆类对草地的贡献等方面的数据，在估算国家N平衡方面存在主要局限性。