【摘要】 土壤质量是土壤特性的综合反映，是揭示人类活动影响下的土壤动态变化的最敏感的指标。建立土壤质量变化评价模式，计算三江平原地区主要耕作土壤表层土（ 耕作层） 的土壤质量矩阵，利用主要耕作土壤表层土的土壤质量指数的变化来定量地分析三江平原地区大面积开荒后土壤质量的变化趋势。结果表明，大面积开荒后主要耕作土壤的表层土的土壤质量指数均呈下降趋势，土壤发生了明显的退化。最后还探讨了这一变化趋势的形成原因。更多还原

【Abstract】 Soil quality comprehensively reflects soil properties and is the most sensitive indicator mirroring dynamic changes of soil condition under the influences of human activities. It is very important for the prevention of soil degradation and the sustainable utilization of soil resources to research the changes of soil quality under the influences of the human activities. The Sanjiang Plain has been built into an important foodstuff base since large area reclamation in 1949. But due to lacking of environmental protection awareness and blindly pursuing economic benefit in the earlier reclamation processes, the soil environment of this area degrades, which will influence the sustainable development of agriculture. This paper establishes soil quality change evaluation model to calculate the soil quality matrixes of the top soils (cultivated layer soil) of the main cultivated soils in the Sanjiang Plain. The Changjing trend of soil quality after large area redamation in the Sanjiang Plain are quantitatively evaluated through analyzing the changes of soil quality indexes of the top soils of the main cultivated soils. Results show the quality indexes of the top soils of the main cultivated soils decrease after large area reclamation. Moreover, with the increment of the cultivation years the indexes decrease more. In the end, the forming reasons of this changing trends is simply discussed.更多还原