【摘 要】
：
成县位于甘肃省东南部的陇南山区,海拔750—2377米,年日照时数1795小时,年总辐射量106千卡/平方厘米,年平均气温11.9℃,无霜期211天,年平均降水量637毫米。全县现有耕地面积
【机 构】
：
甘肃农业大学农学系,甘肃农业大学农学系,甘肃农业大学农学系,甘肃农业大学农学系,
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成县位于甘肃省东南部的陇南山区,海拔750—2377米,年日照时数1795小时,年总辐射量106千卡/平方厘米,年平均气温11.9℃,无霜期211天,年平均降水量637毫米。全县现有耕地面积80.81万亩(区划调查数),95％以上的耕地分布在丘陵山地上,坡陡土薄、土壤养分低,据土壤普查分析,在耕作土壤中有机质含量仅0.7％—1.8％,全氮含量0.05％—0.11％,速效磷10ppm,速效钾110ppm,属于四、五级土壤肥力。冬小麦是该县的主要粮食作物,常年播种面积27万亩左右,占粮食作物播种面积的一半。但长期以来,由于广大农民群众认识上的偏见,在小麦施肥上普遍单施氮肥,不施磷肥,造成小麦贪青晚熟,落黄不好,籽粒
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