寒地稻田钾素状况与平衡

通过对黑龙江省1～3积温带240个农户的施肥情况调查,140户稻农土壤有效钾测试以及试验区水稻钾素收支状况分析,研究黑龙江省钾平衡规律。结果表明,寒地稻田化肥投入钾量平均为50.5kg·hm-2,占稻田钾输入总量的97%。65%以上的稻田钾素用量低,造成寒地稻田土壤钾素偏耗,寒地稻田钾有45.3%的亏缺,60%以上的稻田土壤钾中等或偏低。农民施肥存在较大的盲目性,尤其是钾肥用量过低,使寒地水稻生产中稻瘟病和倒伏发生严重。稻田钾素养分管理的潜力较大。

Potassium statas and balance of paddy field in cold area of Northeast China

A fertilizer investigation with 240 farmers, determination of available potassium in 140 farmers fields and potassium output and input were conducted to find out problems in nutrient management and regularity of potassium balance from 2004 to 2005 in Heilongjiang Province. Experiment results showed that average K application amount was 50.5 kg·hm-2 in rice production. K fertilizer accounted for above 97% of total K input, There was 45.3% deficit between K input and output in Heilongjiang Province. This already resulted in lower available K content of paddy field, so about 60% paddy soils have low available K. Lower K fertilizer application amount and blind fertilizer application may be the reasons for lodging and rice blast. So farmerˉs nutrient manage-ment potentialities should be fully brought out.