东北平原农田防护林网区土地资源系统结构及动态

本文在对东北平原农田防护林网区土地资源系统基本结构分析的基础上,利用典型区域的数据对该土地资源系统动态进行分析。本区的土地资源系统进入广泛的农业开发时间仅五、六十年,但经过强人工作用,已从垦殖期转入衰竭期。只有以人工再生(高投入)的方式才能保证土地资源的永续利用,维持系统的良性循环。否则,仅仅依赖自然再生(低投入)为主要的物质能量返回形式,必然导致粮畜生产带走物质能量,造成土地肥力得不到必要补充,形成土地资源日益衰竭的恶性循环系统。

STRUCTURE AND DYNAMICS OF THE LAND RESOURCES SYSTEM IN THE SHELTER FOREST REGION IN THE NORTH EAST PLAIN

The structure and dynamics of land resources system in the shelter forest region in the Northeast Plain is discussed according to the remote sensing and statistical information from the typical profiles and spots. For agricultural utilization, the land resouces system is made up of five components, i.e. man, land resources, water resources, climatic resources and barren land. The local economy depends heavily upon its land resources, especially farm land. Hav-ing been exploited for 50?0 years from 1930's to ]980's, it has already changed from the re-claiming period into the declining period. There is no waste land to be reclaimed. Facing the increase of population and requirements and the decrease of farmland fertility, proper manage-ment of land resources is indispensible if local economic and living level is maintained. It is imperative to make artificial regeneration (highest input) for the land resources and to Iceep fine circle of the system. If only natural regeneration is relied, the system will be changed to vicious circle.