东北黑土区土壤肥力变化特征的分析

黑土区土壤肥力一直是人们关心的问题。通过选择在黑土区典型县份-德惠市的调查表明,耕地土壤有机质、全氮、有效磷与1980年相比较,分别增加了3.2g kg-11,0.11 g kg-1和5.70 mg kg-1,但有效钾下降了33.3 mg kg-1。土壤中有机质2003年盈余量48.7kg hm-2,氮15.07 kg hm-2,磷25.35 kg hm-2;钾亏损量170.62 kg hm-2。笔者认为,单纯从土壤营养管理角度看,目前黑土区耕地土壤肥力状况似乎没有想象的那么坏。但已有的研究也表明,黑土区耕地肥力的变化与现行的耕作制度有很大的关系。

Analysis of the Changing Characteristics of the Soil Fertilities in the Black Soil Area of Northeast China

Black soils distribute in the cultivated region in the Northeast Plain as well as its surrounding areas.People always pay much attention to the soil fertilities in the black soil area.The investigation in the typical county in the black soil area-Dehui City showed: As compared with those in 1980,the contents of soil 0rganic matter,total N,and available P in cultivated land were increased by 3.2,0.11 and 5.70mg kg~(-1),respectively,but the content of available K was decreased by 33.3 mg kg~(-1).The profits of soil organic matter,N,and P_2O_5 in 2003 were 48.7,15.07,25.35 kg hm~(-2),respectively,but the loss of K_2O was 170.62 kg hm~(-2).It seemed at present that the soil fertility conditions of the cultivated land in black soil area were not as bad as we thought.