Abstract:The occurring, expanding and aggravating of soil erosion in the Changjiang river valley have taken a fairly long period of time. According to analysis of hisorical material, soil erosion in the valley was slight with dense vegetation before the 10th century. From 10 th century to 17 th century, the soil erosion area was expanded. Since mid 17th century, due to the sharp increase in population and excessive exploitation in the mountainous and hilly areas of the valley, soil erosion has been aggravated and become a serious environment problem. It was proved that the unreasonable exploitation of land resources by mankind is a leading factor causing soil erosion.

Abstract:Agriculture industrial structure of Wangdongguo watershed developed from unitary structure with planting food mostly in history to three parts structure including food, fruit and industry by exploring optimize pattern of agriculture structure and regulating agriculture industrial structure according to the characteristics of gully region of loess plateau. By increasing efficiency of water use and fertilizer resources, and gaining highly potential dryland output, average food per product in 15 years reached 4 100kg/km², thus food could be self support basically with one person only possessing 733m ² dryland field; Soil and water loss controlling and vegetation construction have been developed according to the characteristic of soil and water loss on the gully region of loess plateau. Now, soil and water conservation in Yuan physiognomy, slope and gully have been finished in high standard with plant covering rate reaching 43%, soil and water loss controlling rate reaching 92%, soil erosion modulus decreasing to 504t/(km²·a), the controlling effect is notable.

Abstract:The Yangze river basin has a vast expanse and ascendant natural conditions. Nowadays there is a growing concern about the issue of the ecological construction of soil and water conservation. Giving full play to the self restoration capability of ecology, speeding up vegetation rehabilitation and improving ecosystem in a large area are the most effective approach to quicken the management of soil and water loss in the Yangze river basin. It also meets the demand of era. A large amount of the Yangze river basin have a mild climate, abundant precipitation and many kinds of vegetation, plants in this area can grow in whole year, which is very advantageous to the plants growing and the self restoration of ecology. It is indicated by the practice for a long time, the main countermeasures of developing the self restoration capability of ecology are synthetically planning and scientifically returning sloped lands to trees and grasses, closing hillsides to facilitate afforestation, solving the problems of fuel, feed and timbering of the peasants in reason, in the meanwhile, creating environments and conditions for the self restoration of ecology actively.

Abstract:The relation between preventing or controlling flood and drought resistant is analyzed. In order to thoroughly overcome ravages of a constantly escalating drought, it is a important measure to augment groundwater by reverse dredge theory and reverse dredge engineering, traditional engineering join force with reverse dredge engineering, safely regulate water resource in land spatial field and let land have sufficient water resource in every season. It can not only free from drought of the Haihe basin and others basin, but also broke bottleneck restrict of water resource in agriculture and industry.

Abstract:Soil drilling method is applied for root distribution characters investigation of the main forestation tree species on the loess plateau. The results indicate that there is obvious difference in the root distribution characters on different sites, both root density and root biomass on southern slope are smaller than that on northern slope. There are no obvious differences in root distribution depth on stand of different age, but root biomass and root density increased with age. Root extinction coefficient β, is one of the most important parameters in determining the vertical distribution depth of tree species. In this study, results showe that the value of β on northern exposition was more than 0.982, while the value of β on southern exposition was less than 0.982, which indicates that the vertical root distribution depth of Robinia pseudoacaciaon southern exposition is deeper than that on southren exposition. And the distribution depth of fine roots (Φ<1mm) is deeper than that of thicker roots(Φ<3mm), which is in favor of the uptake of water and nutrients from deeper layers, helps the trees to adapt the arid environment, and promoted the growth of the upper parts of the tree.

Abstract:An experiment is conducted for testing the greatest strength of herb root system meanwhile measuring the root diameter under the condition of the greatest tensile strength. It provids where root was tore out and the potential root tensile strength is caculated. The result was revealed that the root average tensile strength vetiver grass of 85 mPa common cetipede grass of 27.3 mPa white clover of 24.6 mPa Juncelles serotinus of 24.5 mPa paspalum dilatatum poir of 19.7 mPa Bahio grass of 19.2 mPa manila grass of 17.5 mPa Bermuda grass of 13.4 mPa. The shear strength test shows that the soil plus vetiver grass root made the shear strength increased, compared to the CK in sandy or clay soil. The feature of holding up soil of herb root network is discussed and the potential capacity of holding up soil ie. the tensile strength of root network is put forword as one of the most important factor. It justifies the basic mechanics theories substituding soft bioengineering approach for the hard engineering approach in completely or partially to hold up soil and slope and resistant against soil erosion and control the landslide and mud rock flow etc.

Abstract:The vegetation in upper reaches of Lijiang river could be divided into five elementary types, such as coniferous forest, broadleaf forest, mao bamboo forest, shrub wood and herb. The hydrological characteristics and functions of different vegetation types are variable, and it differs mainly in reallocation of precipitation, equilibrium of water and hydrological comprehensive adjusting ability. The forest adjusting function on rivers runoff alters as the forest hydrological function changing. On the basis of estimating the hydrological function of different vegetation types, it could be concluded that broadleaf forest is the best vegetation type of sub tropical hydrological function. The ecological rehabilitation strategies are suggested according to the problem of Lijiang river faced and forest vegetation function condition of Lijiang river upper reaches.

Abstract:As a case study in Gansu province, the damp index, days on strong wind, soil texture and vegetation cover in winter and spring in Gansu province on sensitivity to land desertification and their spatial heterogeneity are assessed based on GIS. The result indicates that high sensitive region in Hexi area, middle and light sensitive region in Longzhong and Longdong loess plateau, Qilian mountainous region, Longnan mountainous region and Gannan plateau are light sensitive or non sensitive area.

Abstract:The Daliushu Dam on the upstream of Yellow river will play an important role in rational utilization of water and land resources and improving the survival conditions for local people. But the environmental problems caused by the dam must be pay more attention. Using a Person Land model, the population stress of engineering immigrants on land are calculated. The results show that the population pressure on land increases by 3.9 times after the immigrants enter. The building activities of settlement and traffic facility and land exploitation and utilization may induce land desertification and hence, the area of deserted land rises. So it is necessary to take measures for reducing land pressure and preventing land desertification early.

Abstract:The tasks of the design calculation of rainwater catchment system for life purposes are determining the optimum rate area of rainwater catching field and the first rate volume of water cellar, which are the minimum area of rainwater catching field and the minimum volume of water cellar which can meet the needs of supplying life with water. Taking the characteristic hydrologic year that its frequency is 75% and 95% as the basic calculating years, and taking the precipitations of rainfall periods, the days of non rainfall periods, the days of the maximum non rainfall period and the index of per capita water need as the parameters, according to the precipitation data day by day, the first rate volumes of water cellars and the first rate areas of rainwater catching fields in the mountain areas of west He'nan province are calculated.

Abstract:In the sand area of coastal plain, the soil quality is loose, and it's cohesion is small, so soil erosion on river bank is very serious. A series of soil and water conservation engineering measures developed, which produced a marked effect on protecting the river bank.

Abstract:The necessary of establishment, design and implementation solutions of Web land information system based on Intranet is discussed detailly and developed preliminarily, which has some reference and conductive significance on Chinese networklization land information system establishment.

Abstract:One basic method for the soil and water conservation and ecologic environment constructions in the loess plateau, especially the loess hill and gully area is to return the hillside cultivated land for forestry and grassland. The key issue to execute the project is how to rapidly learn about the current land use situation of the area. The traditional statistical method and on map measurement method are unable to meet the requirements of scientific high efficiency. Combined with the topographic features of the loess hill and gully area, the working process and key technologies of using GIS technology are studied and explored to realize the rapid inspection and checking on the land use situation so as to provide valid methods and basis to realize the automatization and standardization of scientific investigation, planning and management for the land resources in the whole area.

Abstract:The research of soil classification and soil grade evaluation is often based on fuzzy theory. So the traditional method has an inevitable problem about weight matrix which given by some experts. The finally result can be influenced by artificial factor. A new technique of falling dimension named projection pursuit is applied to soil study through using the improved real coding based accelerating genetic algorithm to optimize the projection direction. Thus, it can transfer multi dimension data into one dimension data, through searching for the optimum projection direction to realize the soil classification and its grade evaluation. The method can avoid the artificial disturb, and acquire preferably effect. Thus, it provides a new method to the research of soil classification and grade evaluation.

Abstract:In the production of engineering plan and monitoring control, there are some of problems be pointed, such as the form of rebuild measure, important of the resume ecosystem in the unified plan of the bare gap of mountain reconstruction.

Abstract:Xiangjiang, Zishui, Yuanjiang and Lishui, flowing in mountainous region, are heavy rain rivers with frequently occurring flood water logging disasters. Based on analyzing the data of flood disasters in about ten years, some conclusions about integrate features of the flood water logging disasters are got as follows: high frequency, simultaneously occurrence and regional difference. In temporal distribution, the flood represents seasonal, annual and periodical aspects. In spatial distribution, mountain torrents repeat in upper and middle reaches in mountainous and hilly area. Flooding and water logging interweave repeat in middle and lower reaches over valley plain, coexist in the lower reaches. Furthermore, the severity and frequency of the disasters being enlarged day by day. So redution strategies are put forward in order to reduce the loss.

Abstract:Base on investigations of drought mechanism in Jianghuai watershed of west Anhui province. The authers think that complex natural environment causes frequent drought disaster, imperfect irrigation works, reduces the ability to withstand drought disaster, and current patterning of land use accelerates the damage to crops by drought. In the end, some effective drought countermeasures, which are to enhance the ability to fight drought through tapping new sources of supply and reducing consumption are put forward, to improve ecological environment through building papermaking forestry base, to promote the development of rural economy through readjusting agricultural structure, to speed up industrialization of water resources through reforming managerial system of irrigation works.

Abstract:The cause and harm of water and soil erosion of the area of Danjiang reservoir, for Xichan county lies in the head of the canal of the middle line project of the south water transferred to the north. It is found out that the main problems in the work of water and soil erosion and the countermeasures for water and soil conservation, and for the construction and development of eco environment in the future are put forward.

Abstract:Yongchun county is used as a typical example for south Fujian region. Based on the principles of ecology and sustainable development strategy of the region, the area is divided into smaller eco agriculture construction zones. The resource characteristics of each zone are systematically analyzed. Four development models are established including sustainable and high quality three dimensional production of crop and animal products, high quality fruit and forest production as a key, animal husbandry of reducing grain consumption and establishment of production base for organic vegetables.

Abstract:The principles and guiding ideas of total planning of ecological demonstration county construction are expounded. Based on the analysis of the basic conditions and the constrain factors for sustainable development of Yijun county, the rational targets for ecological demonstration county construction is determined. Ecological agriculture, eco tourism, ecological industry, ecological cities and towns, and protection of water source are determined as the key development domains. The planning of ecological agriculture, one of the five key development domains is detailed.