Zhong Xiang-hao

Assessment and spatial distribution of sensitivity of soil erosion in Tibet

Based on Universal Soil Loss Equation and methods of mathematics model and GIS analysis, this study classified influence of precipitation, soil, topography and vegetation upon sensitivity of soil erosion into five different degrees which are extreme sensitivity, quite sensitivity, sensitivity, less sensitivity and no sensitivity. Assessment map of each factor was generated separately. Integrated assessment map of sensitivity of soil erosion has also been drawn by overlapping function with Arcinfo. Furthermore, the study analyzed distribution characteristics and spatial difference of sensitivity of soil erosion under special plateau environment of Tibet. According to sensitivity degree, some important controlling regions was confirmed so that departments of water conservancy, traffic management and agriculture could make scientific and reasonable decisions for their respective subject planning.Based on Universal Soil Loss Equation and methods of mathematics model and GIS analysis, this study classified influence of precipitation, soil, topography and vegetation upon sensitivity of soil erosion into five different degrees which are extreme sensitivity, quite sensitivity, sensitivity, less sensitivity and no sensitivity. Assessment map of each factor was generated separately. Integrated assessment map of sensitivity of soil erosion has also been drawn by overlapping function with Arcinfo. Furthermore, the study analyzed distribution characteristics and spatial difference of sensitivity of soil erosion under special plateau environment of Tibet. According to sensitivity degree, some important controlling regions was confirmed so that departments of water conservancy, traffic management and agriculture could make scientific and reasonable decisions for their respective subject planning.

Analysis on Landscape Ecological Risk of the Qinghai-Tibet Plateaus:A Case Study on Niyang River Basin

Taking Niyang River Basin as an example, applying with the indices of landscape pattern, the indices of ecological risk of ecosystems are calculated in this paper, which takes the value of ecological loss of main ecosystem as the evaluation standard and takes into account the impacts of probability or the velocity of main hazards and event of the ecosystem. And the grades of ecological risk are assessed. According to the results of assessment, the ecological risk grades of the basin are divided into five classes. From the first grade risk to the fifth grade risk, the values of regional risk indices gradually reduce. The first grade risk areas mainly distribute in Niyang river and its branches downstream and the surrounding areas of main towns. And the basin area of non-valley region and the headstream regions of the branches are the fifth grades risk areas. This evaluation results provide the basis to the regional sustainable development.

Analysis on the Status of Farmers, Agriculture and Countryside, and Development Strategies and Measures in Tibet Autonomous Region

Coordinated and sustainable development of farmers, agriculture and countryside (FAC) is key to realize the national objective of comprehensively developed well-off society. Since the peaceful liberation of Tibet, outstanding achievements have been made in FAC work. However, compared with East and Middle China, there still exists a big gap. The farmers’ net income per capita in 2001 was 1,404 yuan, 962 yuan lower than the nation’s average. In late 90’s the farmers’ income growth slowed down. Agricultural industrialization is at low level, technologies play a small role in agricultural development, rural infrastructure is weak, the rural grass root organization is much underdeveloped, and construction of towns is behind the other regions of China. Based on the problems of FAC development there, this paper proposes FAC development strategies and measures for accelerating rural development in Tibet.Coordinated and sustainable development of farmers, agriculture and countryside (FAC) is key to realize the national objective of comprehensively developed well-off society. Since the peaceful liberation of Tibet, outstanding achievements have been made in FAC work. However, compared with East and Middle China, there still exists a big gap. The farmers’ net income per capita in 2001 was 1,404 yuan, 962 yuan lower than the nation’s average. In late 90’s the farmers’ income growth slowed down. Agricultural industrialization is at low level, technologies play a small role in agricultural development, rural infrastructure is weak, the rural grass root organization is much underdeveloped, and construction of towns is behind the other regions of China. Based on the problems of FAC development there, this paper proposes FAC development strategies and measures for accelerating rural development in Tibet.

Diversity of plant species of alpine grassland in Nakchu of Tibet, China

Characteristics of plant species diversity of two types of grassland communities (alpine meadow and alpine grassland) was examined and the relationship between species diversity and community dynamics was determined using GPS positioning and in situscrutinization of community of alpine grassland in Nakchu prefecture of Tibet Autonomous Region. The result indicated that: ① there was an unobvious difference between grassland communities in terms of richness index of plant, evenness index, dominant index and diversity index. The species diversity index followed the orderKobresia humilis meadow>Stipa purpurea steppe>K. littledalei meadow; ② the original community created high diversity, while the degenerative community suffering from serious disturbance was of low diversity; ③ the diversity of community plants was closely related to changes of species biomass, and the growth and decline of species in the community; ④ grazing disturbance is a key factor of community dynamics, leading to coexistence of various secondary successions of communities, diversified suitable habitats and species diversity improvements.

Dynamic changes of the farmers and herdsmen's income sources in the Tibet Autonomous Region

Based on the Tibet Autonomous Regions statistic yearbooks and the data from the two household surveys in 2002 and 2004, this paper has comprehensively analyzed the pattern of changes on the farmers and herdsmens income sources in the Tibet Autonomous Region since 1990 with the main findings as follows: ① The change of income from the labor payment is the fastest; ② There is no regular pattern of income variation for the household economic activities, the farmers and herdsmens household income generation projects are impacted by the elements like prices and returns, and there is a lack appropriate direction: ③ The income structure of labor payment shows that the income from the farmers and herdsmen working outside grows fastest: ④ The income from the farmers and herdsmens labor payment correlate positively to their net income per capita; ⑤ From the perspective of the variation by region, labor payment income has changed fastest in the counties of Rutok, Nyerong and Khangmar compared the data from the household survey in 2002 with that of 2004.

Quantitative assessment on endangerment degree of rare animal and plant species in Tibet, China

It is of profound theoretical and practical significance to study endangerment status of rare species in Tibet. Index system is firstly set down for quantitative assessment of rare animal and plant species, then endangerment degree of wildlife under special state protection are calculated, which is expressed by value E. The results reveal that Yunnan snub-nosed monkey (Rhinopithecus bieti), Himalayan tahr (Hemitragus jemlahicus) and Gigantic Cypress (Cupressus gigantea) have the highest E respectively in animals and plants. According to value E, all species are categorized into 4 ranks: critically endangered (0.6–0.8), endangered (0.4–0.6), vulnerable (0.2–0.4) and lower risk (E ⩽ 0.2). By comparison of the first five animals and plants of the highest E, each sub-ecozone bears a distinct identity.

A Study of Forest Hydrologic Effect in the Sichuan Basin Region of the Upper Reaches of the Yangtze River

The Sichuan Basin Region is important composition part of the upper reaches of the Yangtze River. Eco-environment change in this region exerts important effect to the middle and lower reaches of the Yangtze River. The forest cover had hugely been reduced from the 1950s to the mid-1970s, and it has obviously been increased since the end of the 1970s, because that the reforestation project has been implemented. The water source conservation capacity in the studied watersheds has been getting better through study and analysis of the methods for assessment of the forest hydrologic effect. It is found that the method of index of the water source conservation capacity can be used to assessment of the forest water source conservation in the big scale watershed in the studied region. In addition, the retention water capacity of the different vegetation vertical zones in the typical mountain in the north-western Sichuan Basin was studied, its result provides the base for protection and building of the forest ecosystem in the mountain area in the studied region.

Effect of Socio-economic Factors on Soil Erosion: A Literature Review

Based on the summarization of the research on man-made accelerated erosion,this paper introduced the four social-economic factors which affect soil erosion including population growth,policy,economic development and land use changes,and reviewed the research methods for the social-economic factors affecting soil erosion both at home and abroad.After that,it is proposed that three aspects of the research need further study: interdisciplinary studies,social-economic models and regional differences.

Analysis on river sediment changes of the upper reaches of Yantze River

The sediment load and river sedimentation of the upper reaches of Yangtze River has been undergoing constant changes as complex landform, large mountain area and plentiful precipitation make the drainage area of Yangtze River very vulnerable to water erosion and gravity erosion. Through analyzing the hydrological and sediment load statistics recorded by major hydrological stations along Yangtze River since 1950s, and editing the accumulation graph of annual runoff volume and annual sediment load, we find out that the suspended-sediment of Yangtze river has been decreasing year by year in Wulong Hydrological Station on Wujiang River. Beibei Hydrological Station on Jialingjiang River, Lijiawan Hydrological Station on Tuojiang River and Gaochang Hydrological Station on Minjiang River, Yichang Hydrological Station, Cuntan Hydrological Station along Yangtze River mainstream share the same experience too. But the statistics obtained at Pingshan Hydrological Station on Jinshajiang River shows the sediment load there has increased. Taking ecological construction, hydraulic engineering construction and precipitation changes into consideration, the thesis analyses the causes for the sediment load decrease of Jialingjiang River, Tuojiang River, Minjiang River and Wujiang River and provides us both scientific foundation for further study of river sediment changes of the upper reaches of Yangtze River, and measures to control river sedimentation.

Evaluation on the essentiality grades of water conserving in Tibet, China

Taking Tibet as an example, the functional essentiality degrees of water resources conserving of regions were discussed in this paper. At first, based on the status of regional vegetation, whether the region has the function of water conserving was made certain. And then, according to the impacted objects of water resources conserving, taking into account the demands for water and regional supply capacities of water and the requirement of environmental protection, the functional grades of regional water resources conserving of Tibet were evaluated in this paper.