我国北方农牧交错带沙漠化的成因、过程和防治对策

在多年研究工作的基础上,总结提出了诸如农牧交错带北移错位、生态位扩张重叠、人口压力危险阈值等一些关于农牧交错带土地沙漠化成因的新理论观点。并论述了农田风蚀、草场沙化、固定沙丘活化及流沙前移等主要类型土地沙漠化的发育过程。提出了适于农牧交错带贫困沙区的"以发展生产、提高生产水平、增加农民收入带动生态环境建设"的沙漠化治理方针和适于乡、村、户三级的"生态网"、"多元系统"、"小生物圈"沙地综合治理开发模式。

Causes,Processes and Countermeasures of Desertification in the Interlocked Agro-pasturing Area of North China

Several new concepts and understandings of desertification and its control in the interlocked agro pasturing area of North China,such as northward protrusion of the interlocked agro pasturing area,expansion of niches and threshold of population pressure,were summarized and presented in this article based on researches for decades.Research on the processes of wind erosion of cropland,desertification of grassland,reactivation of fixed dunes and shifting sand movement reveals that desertification control could be greatly improved if the principle of promoting production development,improving land productivity and increasing net income of local residents were properly carried out in this area.A general model for comprehensive desertification control was introduced.This model includes three sub models,namely 'eco net','multi systems' and 'micro-eco circle' corresponding to the three different spatial scales of township,village and farmer's household,respectively.