陕北黄土地区土地合理利用的途径与措施

The measures of rational land use in the Loess Plateau of Northern Shaanxi Province

本文在土地评价研究的基础上,针对土地利用存在的问题,提出了陕北黄土高原土地合理利用的方向和措施:一是按照土地的适宜性,调整农林牧用地结构,分区建立优化土地利用结构模式;二是造林种草,增加植被,改善生态环境;三是建设基本农田,培肥地力,实现粮食自给;四是小流域综合治理,控制水土流失;五是加强土地管理。

This paper discusses the measures of rational land use in the Loess Plateau of Northern Shaanxi Province. The following measures and recommendations are suggested. Adjusting land use. The key issue is that current land use is not based on land suitability in the study area.Emphasis.must be given to changing land use according to land suitability and local social and economic conditions. Because of the erosion hazard, land should be used for farmland when slopes exceed 15°. The steep cultivated slopes must be abandoned in favour of sown grass and planted trees. Engineering techniques in arable lands. In order to reduce soil erosion and water loss, farmland should include irrigated lands, flood-water sited lands,level terrace fields, check-dam lands, and strip lands in accordance with the regimes of water resources and physical conditions. Check dam need to be constructed along gully beds to retain flood runoff and sediment. Building terraced fields is also a popular way to conserve soil and water. Terraces provide protection from erosion heavy rainfall of up to 40-50mm/24 hours. At the same time, in the terraced fields the output of farm crops for each hectare is usually able that of unterraced sloping lands. Afforestation and sowing grass. Afforestation and sowing grass are major measures to conserve water and soil on the Loess Plateau. Forest should be planted in the mountains and gullies, and grasses and bushes on the slopes. The main kinds of tree and herb are: Caragana sp,locust, poplar, Chinese pine, jujube, pear, apple, alfalfa, sweet clover and Astragalus sp. Grasses and shrubs should be planted first follwoed by an increase in the forest cover. The combination of grass, bushes and trees is the most effective measure to conserve soil and water. Comprehensive management in the small catchment. The problems concerning erosion of hills, rivers, farmland, forests,grassland and roads should be tackled in a comprehensive way. Therefore, The above measures should be implemented in small catchments. Measures taken on the slopes and in the gullies should be coordinated; engineering and vegetative means should be resorted to at the same time; work should be done both to draw benefits and to eliminate hazards. Strengthening land management. We must treasure every inch of land and use it rationally. There is need strictly to implement the land management laws and forestry laws, to ban any excessive timber logging and fuelwood cutting, and to close hillsides and mountains to facilitate afforestation. There are now strict edicts forbidding conversion of forests and grasslands into cropfields; all planned reclamations of land should be carefully appraised and take the environment consequences into account. To encourage afforestation and sowing grass, the state should provide funds for farmers. Thus, the steeply sloping farmlands could be converted into grasslands or forests, decreasing the loss of water and soil erorsion and improving the ecological environment.