Highlights • Cropping system and soil fertility effects on N2-fixation were tested in northern Ghana.• More N2 is fixed in sole cropping than intercropping despite comparable %Ndfa.• Poorly fertile fields give limited grain legume benefits despite enhanced %Ndfa.• Partial N balances are unreliable indicators of cropping system sustainability.• Different grain legumes should be targeted to different sites in the Guinea savanna.

中文翻译：

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加纳北部几内亚稀树草原不同土壤肥力状况和种植制度下豆类对N 2 - 的固定和N贡献

亮点 • 在加纳北部测试了种植系统和土壤肥力对 N2 固定的影响。• 尽管 %Ndfa 具有可比性，但单作中固定的 N2 多于间作。• 尽管 %Ndfa 增加，但肥沃的田地对谷物豆类的益处有限。• 部分 N平衡是种植系统可持续性的不可靠指标。• 应针对几内亚稀树草原的不同地点种植不同的谷物豆类。