Study On Benefits Of "Fruit-grass-pig" Water Models Of And Soil Conservation In Three Gerges Reservior Area Of Chongqing

People start to pay attention to the problems of the natural resources protection and agricultural constantly developing when the status to be serious sucn as population blooming,food lacking, energy limited and environment breaking,etc.It is a very important issue to enable farmers become prosperous as soon as possible by comprehensive proventing water and soil erosion,rational developing and useing land and water resources,developing ecological economy in the destruction of natural resources,serious water and soil erosion areas."Fruit-grass-pig" Water and Soil Conservation models can full use of water,heat,light,soil fertility and other natural resources, enable agriculture,forestry and grass distribute rational in the space industry to increase output and income,intend to coordinate resources and the conflict between the environment.It is one of the important ways to broad the sustainable development of agriculture.In this paper,three "Fruit-grass-pig" Water and Soil Conservation models of Chongqing City of Wanzhou section in Three gorges reservior Area are studied by field observation,indoor analysis and local investigation, economic biological and social benefits of "Fruit-grass-pig" Water and Soil Conservation models are analyzed,and comprehensive benefits is evaluated.Try to chose a high-performanced and "Fruit-grass-pig" Water and Soil Conservation model which can improve soil fertility,increase biomass output and advance rational economy and agricultural constantly development.The study results show:(1)The "Fruit-grass-pig" Water and Soil Conservation models can control soil and water loss, the quantity of surface runoff and soil loss is less than pure forestry model of Florida orange.The index of runoff was the Florida orange—Hokkaido pasture model(0.11m~3/100m~2)＜the Florida orange—Medicago sativa L model(0.26m~3/100m~2)＜the Florida orange—White clover model(0.48m~3/100m~2)＜the pure forestry model of Florida orange(0.89m~3/100m~2).,the index of soil loss was the Florida orange—Hokkaido pasture model(0.14kg/100m~2)＜the Florida orange—Medicago sativa L model(0.43kg/100m~2)＜the Florida orange—White clover model(1.92kg/100m~2)＜the pure forestry model of Florida orange(6.09kg/100m~2)The effect is different as the dissimilar models,the Florida orange—Hokkaido pasture model's effect is prominent,then is the Florida orange—Medicago sativa L model,while the Florida orange—White clover model is not perfect ay all,but all of the "Fruit-grass-pig" Water and Soil Conservation models' effect are all better than the pure forestry model of Florida orange.(2)The effect of soil improving is different in diverse "Fruit-grass-pig" Water and Soil Conservation models.Compared with the pure forestry model of Florida orange,three ruit-grass-pig Water and Soil Conservation models all can effectivelly improve soil nutrient,increase soil fertility;increase the content of big soil pore to promote the infiltration rate;increase the content of the bigger soil paticle to make for the soil nutrient's enrichment.The status of soil physical and chemical properties in the Florida orange—Hokkaido pasture model and the Florida orange—Medicago sativa L model are obviously higher than the Florida orange—White clover model.There is no clear difference in the effect of improveing the soil physical and chemical properties by Hokkaido pasture and Medicago sativa L,and they all are the fine varieties of interplanting grass in the orchards.(3)Compared with the pure forestry model of Florida orange,the Fruit—grass Water and Soil Conservation models can secondry—intercept the rainfall effectively by increaseing the vegetation cover,and prevent water and soil availably,the index of the vegetation cover was the Florida orange—Hokkaido pasture model(85.9%)＞the Florida orange—Medicago sativa L model(81.9%)＞the Florida orange—White clover model(79.0%);can attend to increse the biomass upground and biomass underground by inreasing the vegetation cover and the content of the fibre underground, improveing the soil structure and intercept the rainfall availably in this way.The index of Fresh/Lay was Medicago sativa L(22.10%)＞Hokkaido pasture(21.63%)＞White clover(13.77%),the index of total fibrous root in the 0-30cm layer was the Florida orange—Hokkaido pasture model(158)＞the Florida orange—Medicago sativa L model(146)＞the Florida orange—White clover model(115)＞the pure forestry model of Florida orange(95).The biomass upground and biomass underground of the Florida orange—Hokkaido pasture model and the Florida orange—Medicago sativa L model are obviously higher than the Florida orange—White clover model,it can prove the Hokkaido pasture and Medicago sativa L are the fine varieties of interplanting grass in the orchards secondly.(4)The economic benefit is different in diverse "Fruit-grass-pig" Water and Soil Conservation models.The index of the net benefits was the Florida orange—Hokkaido pasture model(1040yuan/667m~2)＞the Florida orange—Medicago sativa L model(865yuan/667m~2)＞the Florida orange—White clover model(690元/667m~2)＞the pure forestry model of Florida orange(275元/667m~2),the index of the outout-input ratio was the Florida orange—Hokkaido pasture model(1.99)＞the Florida orange—Medicago sativa L model(1.82)＞the Florida orange—White clover model(1.66)＞the pure forestry model of Florida orange(1.29),so the rule of the net benefit and the outout-input ratio are same.(5)The comprehensive benefit of "Fruit-grass-pig" Water and Soil Conservation models is more higher than the pure forestry model of Florida orange,compared with the pure forestry model of Florida orange,the comprehensive benefit of the Florida orange—Hokkaido pasture model is 1.33 times of the pure forestry model of Florida orange,the Florida orange—Medicago sativa L modle is 1.27 times of even the lowest one of the Florida orange—White clover model also is 1.13 times of the pure forestry model of Florida orange.The index of the comprehensive benefit was the Florida orange—Hokkaido pasture model(1.25)＞the Florida orange—Medicago sativa L modle(1.19)＞the Florida orange—White clover model(1.06)＞the pure forestry model of Florida orange(0.94).Compared by the ecological benefits,economic and social benefits,the pure forestry model of Florida orange is the lowest,and by contraries,the Florida orange—Hokkaido pasture model is the highest.