Ecological And Economic Evaluation On The Development Of Vegetative Agriculture Based On GIS

As one of the agriculture structures,vegetative agriculture,which mainly harvest roots, stems and leaves,was defined in the late 1990s. As to this thesis,the concept of vegetative agriculture, ecological and economical benefits and the trend of its development is described firstly. Then the geographical landscape, karst geological, hydrogeological conditions and land utilization type of Houzhai Underground River Basin in Puding county, Guizhou province is analyzed systematically, as well as its urgency and feasibility to develop vegetative agriculture. On above basis, GIS technology ArcViewGIS3.3 software was used to evaluate its agricultural structure. In this paper, some locality characteristic-based suggestion is also discussed for land utilization and agriculture structure adjustment in Houzhai Underground River Basin. The advantage of GIS spatial analysis techniques such as intuition, convenience and speediness was fully embodied during the evaluation process.In this paper, some measures and methods about developing vegetative agriculture in Houzhai Underground River Basin is proposed through analyzing the agriculture structure's status and its problem. Some environmental economics'evaluation methods are applied to estimate its ecological and economic benefits.Firstly, basic farmland with the 0°-5°slope may be used for cultivating cereals to guarantee the fundamental grain and developing contour hedgerow for 5°-15°, the direct economic benefit is 910278.6 yuan. If local peasants make full use of the winter leisure field to develop vegetative agriculture and its profit can reach 2.135136 million yuan. Economic Crop-Pasture Cycle Model to develop vegetative agriculture can produce 6.888 million yuan. And it has great significance to limit soil erosion and improve soil fertility. Thus these agricultural modes can not only ensure the grain that farmers need but also improve ecological environment and increase the income of peasants.Secondly, the farmland with steep slope of 15°to 35°may be classified as forest recovery area. We can plant some suitable legume forage under the trees. Grass'roots can accumulate nitrogen in humus soil. This will not only promote the planting of trees, but also play a positive role in preventing soil erosion and improving the ecological environment. Planting forage below the woods can yield a direct economic value of 1.9071 million yuan in Houzhai Underground River Basin.Thirdly, because the selective forage are excellent grasses, so it have superiority in soil and water conservation, soil fertility improvement and high economic value. Therefore, the author in this paper suggested that natural grassland should be turned into vegetative agriculture. It would produce a direct economic value of 15.92118 million yuan.Finally, in order to develop vegetative agriculture in stony desertification area, some measures, such as planting trees and grasses, should be taken. It can not only increase the ground coverage, reduce soil erosion, but also enhance farmers'income. Stony desertification area with slope below 35°that planting vegetative agriculture has direct economic value of 4.6825086 million yuan.Summing up the above, vegetative agriculture is a new form of agricultural structure, it plays an important role in solving the environmental problems such as soil erosion, stony desertification in Karst area. And it is also very useful for improving soil fertility. It may yield direct economic value of 51.6604272 million yuan in total, and 1,601 yuan per capita. Consequently, it can solve the problem of poverty in this area. It is of great significance to raise the income of farmers.