Key Project of Knowledge Innovation Program, Chinese Academy of Sciences
With the analysis of status and evolvement trend of agricultural water and soil resources in the main grain production area of Northeast China, this study constructed the agricultural land resource database system of typical counties, presented the comprehensive assessment applicable model of agricultural resource potential and sustainable utilization index system of agricultural water resource, and suggested a preliminary scheme of commodity grain base construction layout and agricultural water and soil optimal arrangement in Northeast China.
I. The degradation process, mechanism and driving force of typical black soil were preliminarily illuminated. The assessment index of black soil fertility and reference database was established. The spatial variation characteristics of black soil nutrients were analyzed. The regulation technical system of black soil fertility was integrated through the composite model of tillage, fertilization, and straw returning, which was demonstrated in typical area. The sodic soil water and salt regulation direction and utilization model were proposed. The key techniques of ecological restoration and reconstruction of saline-alkaline land were established in western Songnen Plain.
II. The concentration of Cd, Pd, As and their spatial heterogeneity of main farmland ecosystems were analyzed in Northeast China, and the inter-species difference of heavy metal bioaccumulation for main crops were contrasted, which provided the key scientific basis for the grain safety in Northeast China.
III. The ecological restoration technical system of deplaced farmland ecosystem was integrated from conservation tillage, straw returning, and rotation. The biological amendment technical system, non-pollution grain-soybean production technical system, and agricultural water-saving technical system were established in sodic soil, which were demonstrated and extended in Northeast China, and obatained significant economic, social and ecological benefits.