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机构地区:[1]中国科学院沈阳应用生态研究所陆地生态过程重点实验室,辽宁沈阳110016 [2]中国科学院东北地理与农业生态研究所,黑龙江哈尔滨150081
出 处:《农业系统科学与综合研究》2006年第4期273-275,共3页System Sciemces and Comprehensive Studies In Agriculture
基 金:中国科学院知识创新工程重要方向项目(KZCX2-SW-416)
摘 要:以黑龙江省及其典型市县为代表,分析了黑龙江省典型黑土区近50年农田粮食产量的动态变化及化肥施用对粮食生产的贡献率。研究结果表明:近50年,无论是粮食总产还是单位面积粮食产量,其总的变化趋势是不断增加的,单位面积粮食产量从南到北(即由双城—海伦—克东)逐渐递减,据粗略统计,自20世纪七八十年代施用化肥和有机肥后,其单位面积粮食产量比以前平均增加为:黑龙江省104%,双城市242%,海伦市126%,克东县105%。近30年,黑龙江省和海伦市化肥施用量的变化趋势也是递增的,化肥的施用能促进粮食产量的增加,但化肥对粮食生产的贡献率是逐渐下降的,黑龙江省每千克化肥生产的粮食数量平均由20世纪70年代的15.7 kg下降到目前的9.3 kg,海伦市由70年代的34.7kg下降到目前的8.4k。图3,参5。Choosing the typical black soil regioas in Heilongjiang Province as a representative, we studied the dynamic change of crop yield in farmland and the contribution rate of chemical fertilizer to crop yield in the last 50 years. The results indicated that both of the total and per unit area yield of grain showed increasing trend, the per unit area yield of grain decreased gradually from south to north (e.g. from Shuangcheng city to Hailun city to Kedong county). According to approximate estimate, the per unit area yield of crop increased by 104% in Heilongjiang province, 242% in Shuangcheng city, 126% in Hailun city and 105 % in Kedong county since the application of chemical fertilizer and manure in the 1970s and in the 1980s,. In the last thirty years, the application of fertilizer increased gradually, the use of chemical fertilizer promoted the increase of crop yield, but the contribution of chemical fertilizers to crop production decreased gradually. Grain produced per unit kilogram chemical fertilizer in Heilongjiang province decreased from 15.7 kg in the 1970s to the current 9.3 kg, that of Hailun city decreased from 34.7kg to 8.4kg.
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