Abstract:This paper comprises three articles: "Synopses of Three Gorges Project", "One Must not Be Vague on Matters of Principle" and "More on the Suggestions on Three Gorges Project". All of these describe comprehensively and systematically the disputes on Three Gorges Project, and the instructions from the Central Party and the State Council. Then six questions presented are economic benefits, shipping and silt, emigrants from reservoir area, flood prevention, lessons from Three Gates Gorge Dam and Gezhouba Dam, and substitution of new plan for the original plan. It follows that to solve the requirement of electricity supply in the areas concerned from 1990s on, the best plan should be chosen by comparing some different plans including the Three Gorges Project.

Abstract:Through site investigation and in view of historical experience on rivers harnessing at home and abroad, we believe that the idea of building Three Gorges Project is wrong. The original cost estimate is deliberately set too low, and the actual investiment will be six times over the original estimate, resulting in hidden troubles to induce inflation. It may also bring hidden troubles in utilizing a huge amount of foreign capital. We suggest that the regulation and dredging of river channel should be made so as to keep the whole river in a good condition for navigation. We also suggest to develop tributaries in cascades, a chinese river harnessing experience utilized and enhanced by the America and West Germany. In hydroelectric power development, the easier project should be built first, in line with the capability and requirement of national economy.

Abstract:In thi spaper, three problems are discussed: First, as regards flood control, the idea of waiting for the building of Three Gorges Dam should be abandoned. It is impractical to rely every wishful thinking on the building of Three Gorges Dam; Second, development of the tributaries should be given first priority, and then the main river. The development of hydroelecrtic stations should be incorporated with the development of thermal stations, as local condition may suit; Third, in developing the Yangtze River in the stretch around Sichuan Province, navigation, and not flood control, should have the first priority. River channel regulation work should be carried out before the sedimentation problem is solved. The Three Gorges Dam, with its mammoth magnitude, huge monetary expenditure and very long leading time, will be a main engineering undertaking on the Yangtze River. It must be fully demonstrated whether the dam should be built at all. Such a major issue with far-reaching overall impacts should not bedecided by a few people, in order to avoid the waste of manpower and financial resources and leave harms to our descendants.

Abstract:The Three Gorges Dam is the largest water conservancy project in Yangtze Vally. After constructing Three Gorges Dam, the eco-system of whole Yangtze Vally is going to be changed. The eco-environment, bio-community, and fishery resources around the Yangtze Mouth and its nearby sea area are going to be affected because of the adjustment of Yangtze runoff. Thus, the changing of the Condifion of hydrology, hydro-chemistry and sedimentary environment will change, the composition and distributed pattern of bio-community which will cause the decreasing fo the biobait and the fishery resources to a certain extent.

Abstract:There are superior natural conditions of developing production in the Three Gorges and nearby rigions with a large population, less and low quality of land for cultural agriculture, bad basis of industrial and sideline development and the forest resources being destroyed seriously. Unreasonable land use results in the serious erosion and great damages on the productions. To resolve this issue, it is important to establish a correct guideline of exploiting the region with recovering vegetation in the steep slope, stablizing farm land and building of natural protected district. In addition, some biological and engineering practices must be carried out and every walks of life should attach great importance to the conservation, especially to collapse and slide erosion. If doing so, the losses and damage could be decreased. Finally, it is proposed that the big Dam oft he Three Gorges could not be built until basically being controlled of the water and soil losses.

Abstract:In the construction of the Four Modernizations, there are nine types of soil erosion and water loss by human. It is mainly caused by road buil ding and construction of factories houses in mountain and plain or table areas in the loess plateau, by mining and exploiting and by massed spoils in the development for conservancy and hydroelectric construction. For the more, a great quantity of industry dust and waste from town-run enterprises pollutes water resourse and increases Sediment concentration of rivers and channels. Deforestation for farming and cultivating on grass land and steeper slopes leads to erosion. And it is accelerated by the old traditional faming system which is extensive seeding and worse harvesting, planting along a slope recultivating on economic forest land and so on. People in mountain and table region sin the loess plateau develop the sideline production such as Fungus, the tuber of elevated gastrodia (gastrodia elate), which destroys vegetation and results in more severe erosion. And rubbish and coal ash piled and placed any where in a city increases sediment concentratiou of rivers and channels. Such nine mentioned above would become more worse as the construction develops rapidly.

Abstract:The Cement Plant of Yaoxian County, a large state model interprise, has caused sedimentition downhill movement because it has not taken efficient measures to hold a large amount of stripped loess soil and mountsin cover while as in mining. The released sedimentation has deposited in a reservior, covered fields, blocked traffic, increased the sediment concentratiou to the river channel and threatened the production and living of the local inhabitanbs. The plant has been fined 200,000 Yuan RMB under the Rules for Conservation Work and Critical Regulations on Controlling Cultivation in Wasteland for Good Conservation Work in Capital Construction——Mining, Roadbuildiug, etc. promulgated by the government of Shaanxi Province. Some of the fine was paid for the loss to the local, the others given to the local department of conservation, being used in the comprehensive controlling for soil and water conservation. The plant is also required to take good practice to prevent the new erosion in the continually mining production.

Abstract:The benefits of soil and water conservation mainly include the economic, social and ecological benefits and the benefits of reducing flood and sediment. Reducing of flood and sediment is the basis of other benefits and economical benefit is the aim of other benefits. The important economical benefits include the increasement of agriculture production by holding of water and soil, and social and ecological benefits by reducing of flout and sediment in protection of people's lives and properties and economical construction of water conservancy transportation, industry, mining, cities, countryside and so on.Appropriate analysing and calculating methods for all kinds of benefits are introducd. The benefit of reducing flood and sediment is mainly calculated by conservation and hydrological method in comparision paying attention to the affection of new loss of soil and water and other facts. The benefits related to agriculture, forestry, animal-husbandry and some else should be differentiated in analysing and calculation, the related data of all kinds of benefits in order to determine their proper nature and exact quantity.