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Study region: The Qilian Mountain, northwestern China. Study focus: Land degradation is a global eco-environmental issue. To minimize soil erosion and land degradation, China has implemented several ecological engineering such as “Grain for Green” program (GFG) since 1999. Relationship between vegetation and water budgets in catchments has been widely studied, however very few studies addressed the effects of eco-environmental restoration on water balance in mountain areas, especially with a focus on soil moisture content. Therefore SWAT model was used to quantify the effects of ecological engineering actions (taken place in 2005) on water balance in Qilian Mountain. New hydrological insights for the region: After the ecological engineering, water yield and soil water content experienced an increment of 32%, and 46%. The opposite trend was monitored in runoff and evapotranspiration, which decreased by 48% and 4%, respectively. Therefore ecosystem restoration have increased soil water retention capacity, a greater proportion of precipitation reaching the catchment is absorbed by the soil rather than flowing out of the region as runoff. Therefore trade-offs between environmental sustainability and water resources security should be carefully addressed in arid region that experienced severe water shortages. Keyword: SWAT, Water balance, Ecosystem restoration, Qilian Mountain

The Three Gorges Project has been subject to intense debates regarding its benefits and costs. The environmental impacts of this huge project have been an important focus of these debates since the project planning stage. After the operation of the Three Gorges Dam at full capacity at the end of 2008, new environmental and ecological issues are emerging. This paper gives a brief description of the Three Gorges Project and its environmental impact assessment process, as well as major efforts to control environmental problems brought about by the project. From the long and complicated evaluation process, it is clear that there are large uncertainties and competing opinions regarding the benefits and costs, especially the ecological and environmental ones, of the project even after great research effort. Emphasis here is given to the environmental challenges including: (1) water quality control; (2) water and sediment regulation; (3) biodiversity conservation in the riparian and aquatic ecosystems; (4) environmentally friendly dam operation and regional sustainable development. Opportunities often grow out of the challenges. The Three Gorges Project provides opportunities for grand-scale experiments on the environmental, ecological, and socio-economic impacts of large dams. Local, national, and international concerted efforts and concrete actions should be directed to the mitigation and control of the negative impacts as well as securing the positive contributions of the project across scales. [ABSTRACT FROM AUTHOR]

Ecological regionalization is a base for rational management and sustainable utilization of ecosystems and natural resources. It can provide a scientific basis for constructing healthy ecological environments and making policies of environmental management. In this paper, based on synthetic analysis of the characteristics of the ecology and environments of China, the principles of ecological regionalization are discussed, and indices and nomenclature of ecological regionalization are proposed. The ecoregions on a national scale are divided. The results show that there are 3 domains, 13 ecoregions and 57 ecodistricts. The present scheme can be used as a framework for ecosystem assessment and management. Based on the ecoregions, measurements of management for forest, grassland, agriculture and wetland ecosystems are recommended. The experience and information can be used within and beyond the national scale for landuse planning, biodiversity conservation and ecosystem restoration. [ABSTRACT FROM AUTHOR]

Vegetation and land-use mosaics of shrub land, grassland, farmland and reforested land are characteristic for residential areas of the Wolong nature reserve in Sichuan province, southwest China. The patterns represent a stage in long-term human disturbance and natural secondary succession since deforestation. The aim of this paper was to elucidate the soil-land cover types, soil-slope position relationships on a typical disturbed slope in the humid mountainous region. Soils were taken from four typical land cover types (shrub land, grassland, farmland and reforested land) under four slope positions (upper slope, middle slope, lower slope, foot slope) to study the distribution of soil nutrients and moisture on the transect scales of the slope. To elucidate the influence of land-use and slope position on soil quality, two integrated quantitative indexes were developed to compare soil quality under different land-use types ( QI) and under different slope positions ( PI). The results showed shrub land had the highest QI value, while the QI of reforested land and farmland had lower values. Foot slopes and upper slopes had higher soil quality levels compared to middle slopes and lower slopes. The results indicated that on the slope scale shrub land had high soil quality levels. The results also suggested that in the area of China where the climate favors secondary succession, ‘leave nature as it is’ is a better choice than the policy ‘change farmland to forest land’. [ABSTRACT FROM AUTHOR]

Single nucleotide variations (SNVs) at 5 loci (17564, 21721, 22222, 23823, and 27827) were used to define the molecular epidemiologic characteristics of severe acute respiratory syndrome–associated coronavirus (SARS-CoV) from Beijing patients. Five fragments targeted at the SNV loci were amplified directly from clinical samples by using reverse transcription–polymerase chain reaction (RT-PCR), before sequencing the amplified products. Analyses of 45 sequences obtained from 29 patients showed that the GGCTC motif dominated among samples collected from March to early April 2003; the TGTTT motif predominanted afterwards. The switch from GGCTC to TGTTT was observed among patients belonging to the same cluster, which ruled out the possibility of the coincidental superposition of 2 epidemics running in parallel in Beijing. The Beijing isolates underwent the same change pattern reported from Guangdong Province. The same series of mutations occurring in separate geographic locations and at different times suggests a dominant process of viral adaptation to the host.