类城镇化模式下的水库移民社会分层变迁——基于LRC移民村的研究

国家政策决定移民安置模式,而水库移民类城镇化模式不同于人口自愿流动的城镇化、城中村就地城镇化及并村新建城镇化。原来的社会阶层被打破,在城镇化的3个主要方面:景观、生产、经济均呈现出阶层差异,在搬迁初期,主要表现为景观城镇化,安置稳定后,主要表现为经济城镇化和职业城镇化。新的利益关系格局逐步形成,从而重新形塑移民社会结构,而社会结构的现代化决定着城镇化水平和质量。

黄河小浪底水库风景区旅游环境容量研究

以黄河小浪底风景区为例,建立了水库类风景区旅游环境容量计算指标体系,给出了各指标含义和计算公式,在实用上对小浪底风景区环境容量的计算得出了最适值,并提出了对游客数量进行调控的价格方法.

Source and composition of sedimentary organic matter in the head of Three Gorges Reservoir: a multiproxy approach using δ^(13)C,lignin phenols, and lipid biomarker analyses

A multiproxy approach including bulk organic carbon, δ^(13) C, lignin phenols, and lipid biomarker analyses were applied to characterize the source and composition of sedimentary organic matter in the head part of Three Gorges Reservoir. OM consisted of both natural(autochthonous and allochthonous) and anthropogenic inputs.The natural OM included input from vascular plants,especially non-woody angiosperms. The allochthonous input included plankton and microbial production, likely due to localized eutrophication. Anthropogenic inputs likely derived from petroleum input and/or urban activities.Other anthropogenic inputs were untreated sewage waste.These influences were concluded to be regionally specific point sources of pollution based on relative distributions and on the fact that molecular characteristics of sedimentary OM were not distributed smoothly along a gradient.

Status of two Coreius species in the Three Gorges Reservoir,China

Dam construction alters natural flow regimes which,in turn,cause significant changes in fish communities during and after impoundment. The construction of the Three Gorges Reservoir,from impoundment of the Changjiang(Yangtze) River,China,may have affected native fish species. Thus,the status of two lotic freshwater fish species,Coreius heterodon and C.guichenoti,were monitored in the Three Gorges Reservoir,including fish abundance,individual composition,growth,condition,and mortality. Data on both species were gathered from upstream,midstream and downstream areas of the reservoir and,where available,from studies published before and after dam construction. Lower abundance,slower growth,a less diversified age structure,poorer fish condition(indicated by hepatosomatic index) and higher mortalities were recorded in sites nearest the dam compared with upstream areas. Furthermore,after final impoundment,individual Coreius species inhabiting the area changed,with young individuals becoming more abundant,while upstream of the reservoir the two Coreius species became smaller at a given age. The results show that the status of the two Coreius species was subject to dramatic changes after impoundment.

Structural Features of Zooplankton Cenosis of Southern Kazakhstan Surface Waters

The present condition of Southern Kazakhstan natural reservoirs is represented in the article. The research was held in summer time of 2010. Quantitative and qualitative features and dominating types of zooplankton of the individual reservoirs are shown. It is detected that the waters of the South Kazakhstan oblast （region） are inhabited by 70 types of zooplankton organisms of different taxonomic groups, whose association to certain reservoir depends on the hydrochemical indicators of the aquatic environment.

Algal community composition and abundance near the confluence of the Jialing and Yangtze Rivers and in Shuanglong Lake in Chongqing,P.R.China

To understand the potential impact of the Three Gorges Reservoir on the aquatic ecosystem after the damming of the Yangtze River,we studied the community composition and temporal abundance distribution of algae in two types of water bodies:a segment of the Jialing River near its confluence with the Yangtze River as an example of the river-lake type,and Shuanglong Lake in Chongqing as an example of the lake type.In total,107 species belonging to 58 genera of 7 phyla were identified in the study area of the Jialing River,dominated by three groups with 49.5% diatoms,29.0% chlorophytes,and 11.4% cyanobacteria in the community composition.There were 122 species belonging to 66 genera of 8 phyla in Shuanglong Lake,dominated by the same three groups with 19.7% diatoms,48.4% chlorophytes,and 22.2% cyanobacteria.The densities of total algae and individual dominant groups were all much higher in the lake.More species of diatoms were found in the river-lake segment;whereas more chlorophyte species and cyanobacteriaum species were in the lake.There were 17 dominant species including 8 diatoms,4 chlorophytes,3 cyanobacteria and 2 cryptophytes in the river-lake segment,and 21 species in the lake,including 2 diatoms,9 chlorophytes,6 cyanobacteria,3 cryptophytes and a dinoflagellate.In eutrophic conditions,chlorophytes and cyanobacteria may proliferate in a lake-type area and diatoms may cause algal bloom in a relatively faster-flow lake-river type area.

Google Earth-based dynamic visualization system for storm surge flood routing

To describe the dynamic process of flood routing intuitively and realistically when storm surge disaster occurs,a method for ArcGIS data and Google Earth(GE) data integration is proposed,which realizes the importing and integrating of basic geographic information into GE. Based on SketchUp and AutoCAD software,threedimension(3D) visualization of seawall and other tidal defense structures is achieved. By employing Microsoft Foundation Class Library(MFC),the related system modules and storm surge flood routing dynamic visualization system are developed. Therefore,dynamic visualization of flood routing process and interactive query of submerged area and inundated depth are implemented. A practical application case study of Tianjin Binhai New Area provides decision-making support for coastal seawall planning and storm surge disaster prevention and reduction.

Impacts of water release operations on algal blooms in a tributary bay of Three Gorges Reservoir

Water release operation is crucial for water quality in large reservoirs such as Three Gorges Reservoir(TGR),because it determines the hydrodynamics and hence the self-purification capability.As algal blooms were often observed in some tributary bays of TGR during the release periods,high frequency field observations were carried out in a typical eutrophic tributary bay(Xiangxi River) from February 9 to May 10,2009.In this paper we assess the hydrodynamic behaviour,density stratification,and trophic status in this bay,respectively using a series of observations for flow,physical,chemical and biological parameters.Then,we analyze the effects of reservoir release operations on algal blooms using correlation analysis method.An empirical prognosis is concluded for the likelihood of algal bloom occurrence as a function of daily fluctuation of water level(DFWL) and water temperature.Our results indicate that during the release period,the algal bloom occurrences are closely tied to the DFWL in that if the ratio of DFWL to total water depth ranges from -10×10-4 to 0,the possibility of algal blooms may reach up to 70%,and if the ratio is less than -10×10-4,then that risk can be significantly reduced to less than 10%.This paper finally suggests that a wave-type water release operation should be beneficial in reducing bloom frequencies in the tributary water bodies,which is helpful for TGR water quality management,especially for the water release operation optimization.

Induced earthquakes in the development of unconventional energy resources

It has long been known that human activities such as waste fluid disposal and reservoir impoundment may cause earthquakes. Recently, anthropogenic activities to tackle the increasing energy demand and to address climate change issues are also reported to induce earthquakes. These activities have a common attribute in that fluids are injected and extracted underground and induce spatiotemporal changes of pore pressure and stress, which may cause slip on faults. Induced earthquakes not only pose significant impacts on seismic hazard assessment and preparation, but also raise the question to the society as how to balance the economic needs of resources development and the public's concerns about potential environmental impacts. Here we review the observations of fluid-injection/extraction induced earthquakes, ground deformation associated with these activities, and their physical mechanisms. Furthermore, we discuss the influences of induced earthquakes on seismic hazard models, regulatory policies on these anthropogenic activities, and current development of academic, industrial and government initiatives and collaborations in order to understand this intriguing phenomenon and address associated challenges.