| Yangtze river is the golden channel in our country, with the watershed area about 1800 000 km2, and occupy about 1/5 area of the whole country; with the population about 0.4 billion, which occupy 1/3 of the general population; its GDP is about 1/3 of that in the whole country, including 9 provinces, cities and municipality, so the Yangtze river watershed is holding the balance in he whole country. Especially the watershed includes the economy developed east area and poor region in middle-west, and with the typical and representative entironment structure and economy development. However, because of the absurd utilization overindulge management, the entironment of the Yangtze River watershed is in havoc. The soil and water loss is the main problem, which influence the harmonious development of nature and the human beings. The most concentrated area of the soil and water loss in this area is the middle and upper reaches. According to investigation, the sloping plow land, barren hills and slopes, sparse young woodland are the main erosion land use type in the middle and upper reaches of the Yangtze River. Under taking some measure, these kinds of lands can play self-restoration ability to achieve renewing plants, soil and water conservation, constructing good ecosystem. It's because that most of the Yangtze River watershed area locates in the east-Asia tropic monsoon region, with superior nature condition, and annual rainfall about 1100mm, flush precipitation, moderate climate, and various kinds of plants, the plants in most of this area grow nearly during the whole year, so it's in favor of multiply and restoration. Lately, the development of the restoration ecology stress no matter in the terrain or in the theory, it should span the border, effective restoration ask for more cooperation in more regions even nations, in year 2004, the theme of the 15th international ecology restoration is restoration landscape and design. Guiding by the trend of lately ecological restoration, this paper selects 10 spots in the middle and upper reaches of the Yangtze River, e.g. bishan in Chongqing, wuxi, taibai in Shanxi, liangdang in Gansu, chishui in Guizhou, yaoan in Yunnan,huilong country in Jiangxi, anyi country inJiangxi, pingchang country in Sichuan and yilin in Hubei, which are in the Yangtze River "Soil and Water conservation ecological restoration Project" experimental unit, span the terrain boundary, by the investigation of the plants, soil, climate etc natural information and population, economy etc social information of the project spots, base on the climate region, plant trip, physiognomy unit, soil geology and human influence, cluster these 10 spots into 4 different typical area, then choose 4 representative areas form the 10 spots to studying. Firstly, research on the change of the soil fertility between before restoration and after restoration; secondly, the plant change between before restoration and after restoration, and the factors influence the plant change. Therefore take different measures in these 4 representative areas, and so did the restoration plant inspect, analyze separately every representativearea, and then compare the main process and influence factors during the restoration of soil and water conservation vertically and horizontally; carry on comprehensive benefit analyses and study restoration of water and soil conservation to the improvement of ecological environmental and development of society and economy. The study results are:(1) Yunan, yaoan belongs to plateau-basin north subtropical zone evergreen broad leaf forest belt in the mid-yunnan; Guizhou, chishui,Chongqing, bishan,Sichuan, pingchang belong to Sichuan basin evergreen broad leaf forest belt of middle subtropical zone; the climate belt of Jiangxi, anyi,Hunan, longhui belong to xiang-gan hills middle subtropical zone evergreen broad leaf forest belt; Chongqing Wuxi, Hubei yiling, Shanxi taibai, Gansu liangdang locate in Qinling Mountains and Daba mountain area, type of climate is north subtropical zone, vegetation in this area is mix and evergreen broadleaf forest of the needle-broadleaf tree belt, comprehensive climate, physiognomy and vegetation characteristic, divide these areas into one kind, belong to north subtropical zone, Qinling-bashan mountain region of mix and evergreen broadleaf forest of the needle-broadleaf tree belt.(2) Choose one of the four typical districts as representative spot to go on research the soil fertelizer,the pH value of the soil is acid and after repairing, the acid in the four investigation is to strengthen, this is because under the cover of the natural vegetation, the accumulation and resolving of the organic matter influence the saline constitution of the soil, thus influence the acid and alkalescence of soil. Because fallen leaf can produce organic sour, this is one of the influence factors among them that pH increases after repairing too. Organic matter is one of the most important component of soil, , it influence soil water, hot, air etc various kinds of fertility factors in soil physical property and have an important influence on the soil structure, ploughing too, the organic content of soil has been improved after the restoration; respectively: yangpai small watershed in yaoan country, yunan 127.2%, longjin town small watershed in anyi, jianxi 20.57%jianshan No.1 small watershed in pingchang, sichuan 12.2%, hongchiba small watershedin wuxi ,chongqing 40.6%. Among them the organic content increased most is Yaoan of Yunnan, the main reason is the introduction of the Australian Acacia with better nitrogen fixation, and improves the soil fertility at the initial stages of ecological restoration.(3) Though the ways to investigate the vegetation in four trial zone are different, according to the result of the analysis, the covering degree of vegetation has been improved after restoration; the improvement of vegetation cover degree is useful to water and soil conservation and stability of forestry ecosystem. The vegetation cover relates with the location of the ecological restoration area, take pingchang, Sichuan as an example, one region with different flow area, its effect of ecological restoration is different, the main constructive plant type is not the same , the bear effect degree is...
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