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农业的发展与生态关系很大,因此从生态系统观点研究农业的发展是十分必要的。从生态观点来看河北省的农业生产,这方面则存在着许多不可忽视的问题:(一)盲目垦荒,草原招致破坏,引起气候恶化。如坝上地区就是十分典型的。张北县总土面积4251平方公里,折合为637万亩。解放初1949年草滩面积有287万亩,草场复盖率达45%,到1978年底草滩面积只剩下75万亩,复
The development of agriculture has a great relationship with ecology, so it is very necessary to study the development of agriculture from the viewpoint of ecosystem. From the ecological point of view of agricultural production in Hebei Province, there are many problems that can not be ignored in this regard: (a) blind reclamation and reclamation of land, grasslands lead to destruction, causing climate deterioration. Such as dam area is very typical. Zhangbei County total earth area of 4251 square kilometers, equivalent to 6370000 acres. In 1949, there were 2.87 million mu of grassy beach area in 1949 and 45% coverage of grassland. By the end of 1978, there was only 75 million mu