长期定位施肥对砂姜黑土肥力及生产力的影响研究

长期定位试验研究化肥与有机肥配施对砂姜黑土土壤肥力和作物产量的影响结果表明 ,长期施肥可提高土壤碱解氮、速效磷及有机质含量 ,不同肥料组合间差异较大 ,以有机肥与化肥配施处理效果最佳 (但同时必须重视K素的投入 ) ,土壤速效钾仅全部施用有机肥处理有所增加 ,单施N、P化肥处理下降最多 ,至 15年后下降2 5 .8%。长期未施肥处理 (对照 )碱解氮变化最大 ,较试验前下降 2 6 .5 % ,其他养分指标变化较小。有机肥与化肥配施处理产量前期不及单施化肥处理 ,中后期则反之。砂姜黑土基本生产力随种植时间延长而渐降 ,土壤对秋粮大豆或玉米的供肥能力高于小麦。

Effects of a long-term located fertilization on the fertility and productivity of Shajiang Black Soil

A systematic study concerning the effects of a long term application of chemical fertilizers,organic manure separately or both of them on the soil nutrient content,basic productivity and crop yield in Shajiang Black Soil was conducted. The results show that the long-term fertilization can increase the contents of soil organic matter,available N and P.But there is a greater difference among the fertilizer combinations,the effect of the treatment applying organic manure combined with chemical fertilizers is most remarkable in several treatments,but the application of potassium must be attached importance at the same time. Only the treatment applying single organic manure can increase the soil available K content,the descending rate of the treatment applying chemical N and P is the fastest in all treatments,and it decreases by 25.8%during 15 years. The change of available N without fertilizers (CK) treatment is greater than that of other nutrients,being 26.5?wer than that of 15 years before,but other nutrients change little. The crop yield with the treatment applying organic manure combined with chemical fertilizers is lower than that with the treatment applying single chemical fertilizer in prophase,but it is higher in other phases. With the time prolonging,the basic productivity of Shajiang Black Soil is declining,and the soil supplies more nutrient for maize or soybean than wheat.