Land Use of the Three Gorges Reservoir Area and the Effect on Its Landscape Pattern in the Recent 50 Years

The paper makes detailed analysis on the changing processes of the main types of land use in Three Gorges Reservoir Area through the techniques of RS （Remote Sense） and GIS （Geography Information System）. Based on the theory of landscape ecology, many types of landscape pattern indexes are calculated and made correlation analysis. The results indicate that： in 1995 the ecological environment of Three Gorges Reservoir Area was the most vulnerable in the recent 50 years, but resumed in 2002; the landscape pattern diversity index, fractal dimension index and fragmentation index has close correlation with the area of land use/cover change （LUCC）. The research also releases that the increase of the cultivated land, grassland and construction land deteriorates the landscape ecological pattern, while the increase of forest land area will help restore the landscape ecological pattern to its original state. The rapid change of grassland is an important index of the change of landscape pattern, because it has the most effect on change of landscape pattern index.     

Study on Landscape Pattern in the Jinshajiang Xerothermic Valley Using RS and GIS——Taking Yuanmou of Yunnan as an Example

Based on the data of Landsat-TM in 1986 and 2000 and with the applied indices of landscape pattern, an analysis is carried out on the landscape pattern with its evolution in Yuanmou County of Yunnan Province inside the Jinshajiang Xerothermic valley area and a forecast is given on the changing tendency of the landscape pattern in the county with Markov Chain Model. The result shows that the production landscape like irrigated farmland and construction land in town and country as well as ecological building landscape in boondocks were enlarged during 1986-2000. Also the patch shape was regularized and the patch shape index and dimensionality were degraded. The landscape pattern was tattered and the heterogeneity index and Evenness degree were increased but the dominance degree was degraded. The key elements with lower stability cover grassland, water body and bush land. The future transformation of landscape pattern will centralize in construction land‘‘s occupation in irrigated farmland, non-irrigated farmland and grassland, the transformation of non-irrigated farmland to irrigated farmland, forest and sparse wodland or orchard, construction land‘‘s occupation in grassland and cultivation of it into sloping non-irrigated farmland and forest‘‘s degeneracy to bush land, sparse woodland and grassland. The main measures to improve virtuous development of landscape in the xerothermic valley are suggested.     

Discussion on Landscape Ecosystem Planning of Small Basins in the Qinghai.Tibet Plateau——Taking Nieruzangbu Basin as an Example

In this paper, taking Nieruzangbu as an example, it is discussed that how to plan landscapes of small basin in the Qinghai-Tibet Plateau. With analyzed the status and character of landscape structure through the use of landscape diversity indexes and landscape dominant indexes, some major problems in the landscape ecosystem are pointed out. On the basis of regional restrictive principle and compliance principle of resources, environment and economy, Nieruzangbu Basin is divided into three landscape function areas. According to the demands of each function area, landscape structure planning is carried out to improve ecological environment through optimization and adjustment of landscape structure in Nieruzangbu Basin.     

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

0IntroductionWhether the regional ecosystems are securityis determined from two aspects which arethe ecological healthandthe ecological risk.Ecologi-cal riskreferstothe sufferedinterferences and disas-ters of ecosystems,and the damaged possibilities ofecosystems structures andits function.The relation-ship betweenecological riskandecological securityisinverse function.Therefore,the analysis of regionalecological riskis ani mportant aspect of studying onecological health,which can provide plann…     

Two Village Ecosystems in the Upper Minjiang River, China： A Comparison of Emergy Flow

By using the concept of emergy and method of emergy analysis, this paper has studied two mountain settlement (village) ecosystems in two aspects: input and output of energy in the agro-systems and the use of fuel energy. The result reveals that the settlement agro-system in the valley of Minjiang River is better in both structure and function than that at the so-called half-high mountain. The former one is higher than the latter one regarding such indices as emergy yield ratio, labor productivity of emergy and emergy sustainable index, but lower than the latter one regarding environmental loading ratio. In terms of fuel emergy, the settlement in the valley enjoys more diversified sources and is less depending on bio-energy while the settlement at the half-high mountain has only one source (i. e. fuel wood), much depending on bio-energy, may exert a greater pressure on environment.     

Occurrence Conditions and Process Analysis on Fluidization of Valley Type Landslide： Example of the Fluidization of Landslide in Qiongshan Ravine, Danba

0IntroductionFluidization of landslideindicates the action andprocess of an alivelandslide motion of conver-ting fromsliding state to fluidal disposition due tovibration and watering function occurred in processof landslide’s mediumand high velocity movement.Research onfluidization of landslide is a major sub-ject inthe field of landslide and debris flowstudies,which has a significance of deepening people’s un-derstanding of landslide disaster and rules of debrisflow occurrence.For example,S…     

雅鲁藏布江中下游地区湿季降雨量的空间分布模型

对于水文气象站点稀少的青藏高原山区,获得较为精确的降雨空间分布信息是进行降雨径流模拟的前提。该文利用GIS手段和多元回归方法,建立了雅鲁藏布江中下游地区旱、偏旱、正常、偏涝、涝等5种类型年份的湿季(5—9月)降雨量的空间分布模型。结果显示:多种地理地形因子对湿季降雨空间分布均有重要影响。统计分析表明:(1)雅鲁藏布江中下游流域地形复杂、降雨站点稀少,回归分析中的地理、地形因子共线性问题突出,方差扩大因子法、Pear-son相关系数法和因子分析法的组合应用是识别和解决共线性问题的有效方法;(2)影响湿季降雨的局部地形因子表达存在着最优空间尺度,15—25km半径范围内的平均坡度、平均坡向、开放度值与降雨也有较高相关性,但考虑其他局部地形因子后,开放度对降雨空间分布的影响可以忽略。     

岷江上游景观变化研究--以汶川县为例

运用3S技术分析了岷江上游地区的景观变化,发现该区的景观是在逐年的破碎化,有林地是唯一一种减少的景观类型,草地、灌木林地、经济林、耕地和居民用地的面积在逐年的增加,而河流、湖泊和冰雪,裸岩的面积没有变化。在此基础上分析了景观变化的原因,认为人文因素是其变化的主要原因,人口的增长,加上片面追求地方经济的发展,森林资源的不合理、过度的开采,草地资源过度放牧和超载,导致了该区的生态环境受到巨大的破坏,森林面积减少,覆盖率降低,草场退化,水土流失严重。     

雅鲁藏布江河谷地区黄土的物理力学指标统计分析

在野外调查和室内试验的基础上,利用Origin7．0软件对西藏雅鲁藏布江中部流域河谷地区黄土的物理及力学指标进行统计分析,建立了土性指标的线性方程,并探讨了各个指标间的相互关系,结果可作为该地区地基基础可靠性设计相关参数合理选取的理论依据。     

基于HHT的雅鲁藏布江径流变化周期及趋势分析

 采用Hilbert Huang变换对雅鲁藏布江干支流上的10个水文站1956-2000年天然径流资料进行分析,探讨了雅鲁藏布江流域年径流变化的近似周期及其演变趋势。研究结果表明,雅鲁藏布江全流域范围内存在约3、6~8、9、11~13、16~17及22~24 a的近似周期。同时研究还发现,雅鲁藏布江干支流在20世纪60年代左右径流量较大,但在进入60年代中后期之后,年径流量呈逐渐减小的趋势,这种趋势在80年代附近达到极小值,此后径流量逐渐回升,并在90年代后逐渐进入相对丰水期。     

黑河中上游草原蝗虫生态分布与生境的关系

以黑河中上游天然草地为例,采用野外调查和定量分析方法,研究了不同草地蝗虫组成、生态种组分布及其与生境的相关关系.结果表明:黑河中上游天然草地的地形、气候条件和土壤、植被组成具有明显异质性;连续4年野外采集蝗虫38种,隶属于3科11属,32个多布种蝗虫在相关性系数0.50处,聚为8个生态种组.蝗虫具有极为广泛的生态适应性,同时草原区的生境决定着蝗虫的地理分布格局,研究区蝗虫主要分布在海拔2000～3000 m的祁连山地.温度因子是蜱虫种属组成的促进因子,其他因子为抑制因子;温度与降水量是蝗虫密度的促进因子;极端最低温与蝗虫种属组成存在极显著关系,与蝗虫密度存在显著关系.     

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. Foundation item: Supported by the National Natural Science Foundation of China (50099620) Biography: ZHONG Xiang-hao (1942-), male, researcher, research direction: mountain environment and ecology.     

Mercury speciation and spatial distribution in surface waters of the Yarlung Zangbo River,Tibet

The Yarlung Zangbo River is the highest river in the world. It flows from west to east through the southern part of Tibet. The mercury (Hg) speciation and distribution in surface waters and soils near the bank of the Yarlung Zangbo River and its two tribu-taries, the Lhasa and Niyang Rivers, were investigated in June 2007. Simultaneously, major water quality parameters were also measured at the same stations. Total Hg (THg) and total methylmercury (TMeHg) concentrations in surface waters of the Yarlung Zangbo River ranged from 1.46 to 4.99 ng/L and from 0.06 to 0.29 ng/L, respectively, representing the background levels in river systems of the Tibetan Plateau. Particulate Hg (PHg) accounted for 69% of the THg, and the two Hg species had a significant relationship (r=0.990, P<0.01). Approximately 61% of the spatial distribution of THg was controlled by the concentrations of total suspended particles (TSP). Reactive Hg (RHg) concentrations ranged from 0.10 to 0.36 ng/L, and this fraction may play a weak role in terms of the transport and fate of Hg in surface waters. Dissolved methylmercury (DMeHg) constituted 71% of the TMeHg and was significantly correlated with TMeHg (r=0.746, P<0.01). The spatial distribution of TMeHg is not strongly affected by environmental factors such as THg, RHg, temperature, pH, dissolved organic carbon (DOC), and TSP. In addition, the inflow of both the Lhasa and Niyang Rivers probably influences the concentrations of THg in surface waters of the mainstream, but such an effect is not obvious for TMeHg.     

雅江流域多源遥感驱动的SRM模型精度影响因子研究

利用多源遥感数据驱动SRM模型模拟雅鲁藏布江4个不同水文站控制流域的融雪过程,分析流域特征(面积、地形地貌因子、植被类型)、模型输入变量(气温、降水、积雪覆盖率)对遥感驱动SRM模型模拟精度的影响.研究表明:遥感驱动的SRM模型在雅鲁藏布江研究区域模拟精度较高,NSE系数达到0.83以上;但其精度受流域面积大小的影响,具有尺度阈,在一定面积尺度上模拟精度最大,流域地形越复杂,其模拟效果越差;植被覆盖类型影响融雪径流过程的模拟,进而影响模拟结果;模型3个主要输入变量气温、降水、积雪覆盖率对遥感驱动的SRM模型的模拟精度同样有很大程度的影响.研究结果对资料匮乏的高海拔地区水资源利用具有重要意义,同时可为遥感驱动的SRM模型的推广应用提供有效支撑.     

黑河中上游流域水文区划分析比较

选取黑河中上游流域11个水文站点反映流域降水径流特性的7个区划指标,分别应用模糊聚类法和集对分析进行水文区划研究.2种方法比较分析结果表明,应用模糊聚类法将该流域划分为5个子区更为合理.所得分区结果有助于进一步认识该流域水文现象的形成、分布和变化规律,也为黑河流域水文站网合理规划、布设提供了基础,同时也为解决水文资料移用和水资源合理开发提供了依据.     

长江中下游河流沉积物磁性特征初探

通过多参数磁性测量分析,探讨长江中下游干、支流河流沉积物的磁性特征,为研究长江水沙环境积累基础资料.研究结果表明,长江中下游干、支流河流沉积物中,磁性矿物类别均以磁铁矿为主,晶粒均以假单畴-多畴为主.与干流相比,支流沉积物中不完整反铁磁性物质含量较多,晶粒较细,Χ值仅是干流的1/10.随着支流泥沙的汇入,入江口以下江段沉积物的磁性特征相应发生变化.支流泥沙物源贡献的研究是探讨长江中下游干流沉积物环境特征的主要因子.