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1.
The Mekong River’s natural resources offer large benefits to its populations, but it also attracts the interest of foreign investors. Recently, Chinese firms, banks and government bodies have increasingly invested in large hydropower projects in the Greater Mekong Sub-Region. Due to China’s rapid economic growth, its rapid industrialisation and its limited domestic natural resources, the Chinese government has issued the ‘Going Out Strategy’ which promotes investments in overseas natural resources like water and energy resources. In search for climate-friendly low-carbon energy, cheap electricity and access to a growing market, Chinese institutions turn to Southeast Asia where Chinese institutions are currently involved in more than 50 on-going large hydropower projects as contractors, investors, regulators and financiers. These Chinese institutions have influence on environmental and social practices as well as on diplomatic and trade relations in the host countries. Currently, there are major gaps in understanding who is engaged, why, how and with what impacts. This paper therefore aims to assess the motives, actors, beneficiaries and the direct and indirect impacts of China’s investment in large hydropower projects in the Greater Mekong Sub-Region. The authors use the ‘Rising Powers Framework’ to assess these issues, which is an adapted version of the Asian Drivers Framework.  相似文献   

2.
Natural protected areas (NPA) are portions of the Mexican territory where the original environment has not been modified and which are protected in order t  相似文献   

3.
The surface of the earth has been continuously sculptured by the exogenetic processes primarily by the climatic hydrological attributes. Over the sequential phases of evolution of earth, the climatic attributes have altered. The alternative processes such as glaciation and declaciation, fluctuations of sea level and variability in rainfall pattern have changed the surface configuration through maneuvering the operations of the geographical processes. The issue of climate change has become a matter of scientific concern all over the world as the human communities are facing severe problems manifested in the form of flood, drought and submergence of low-lying coastal regions, estuaries and deltas. The present study is an attempt to understand the nature and extent of climate change (1890–2012) and related sea level rise (1970s–2010) in the deltaic Sundarban region of India since the last century and how far they are impacting the erosion–depositional processes (1925, 1926–2014). The changing trend of mean annual temperature, rainfall pattern and frequencies of tropical cyclones has been studied in detail, and spatiotemporal changes of geomorphic environment in different reaches of the study area have also been monitored with available multi-temporal geospatial data. The observation reveals that the flat sandy coastal belt and low-lying island in the extreme southern part have been severely affected by wave dash and seasonal storm surges which are mostly responsible for vigorous erosion. On the other hand, high tidal velocity is observed along the exposed concave bank in the upper–middle reaches of the Muriganga estuary and exposed outer bank in lower–middle reaches of Saptamukhi estuary. The thalweg line, which is very close to the river bank in those reaches of estuary, intensifies the hydraulic pressure along marginal parts of river bank which leads to erosion. Depositional activities are mostly observed along the sheltered inner reaches and convex river banks of the estuaries due to less effective tidal rushes, shallow channel depth, marginal flow velocity and gentle channel slope. Therefore, erosional and depositional processes cannot be explain by the relative mean sea level rise, because increasing mean sea level will affect the erosional processes uniformly in the entire estuary. In this present study area, both the erosional and depositional processes are simultaneously active depending on geographical exposure, sinuous channel pattern, channel depth and lithological compositions.  相似文献   

4.
Policy-making in social-ecological systems increasingly looks to iterative, evolutionary approaches that can address the inherent complexity of interactions between human wellbeing, provision of goods, and the maintenance of ecosystem services. Here, we show how the analysis of available time-series in tropical delta regions over past decades can provide important insight into the social-ecological system dynamics in deltaic regions. The paper provides an exploratory analysis of the recent changes that have occurred in the major elements of three tropical deltaic social-ecological systems, such as demography, economy, health, climate, food, and water. Time-series data from official statistics, monitoring programmes, and Earth observation data are analysed to explore possible trends, slow and fast variables, and observed drivers of change in the Amazon, Ganges–Brahmaputra–Meghna and Mekong deltas. In the Ganges–Brahmaputra–Meghna delta zone, increasing gross domestic product and per capita income levels since the 1980s mirror rising levels of food and inland fish production. In contrast, non-food ecosystem services, such as water availability, water quality, and land stability appear to be deteriorating. In the Amazon delta, natural and anthropogenic perturbations are continuously degrading key ecosystem services, such as carbon storage in biomass and soils, the regulation of water balance, and the modulation of regional climate patterns. In the Mekong delta, rapid economic development, changing land-use practices, and salinity intrusion are progressively putting more pressure on the delivery of important provisioning services, such as rice and inland aquaculture production, which are key sources of staple food, farm incomes, and export revenue. Observed changes in many key indicators of ecosystem services point to a changing dynamic state and increased probability of systemic threshold transformations in the near future.  相似文献   

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7.
The paper examines the role of environmental norms in Chinese overseas investment in hydropower dams, exemplified by Sinohydro’s involvement in the Bui Dam in Ghana. While the investment of Western companies in hydropower dams in the global South is decreasing owing to changing notions of sustainability in the West, the investment of Chinese companies in hydro dams in Africa, Southeast Asia and Latin America is accelerating at great speed. The emergence of Chinese companies in international markets in the context of China’s Going Abroad strategy has sparked a debate on whether China can be considered a norm-changer in international development. The paper considers this question in the context of the status of environmental norms in Sinohydro’s investment in Ghana’s Bui Dam. The paper argues that the role of international norms in Chinese investment is dependent on two factors: the contractual arrangements under which Chinese companies operate abroad and the political institutions of host countries.  相似文献   

8.
The indoor concentration of suspended particulate matter (SPM) was measured in forty-four retrofitted and tight dwellings, which had electric cooking and were central heated and where the basic ventilation rate in median amounted 0.23 air changes per hour as measured with a tracer dilution method. The indoor concentration of SPM was in median 230 μg/m3 with a strong correlation to the tobacco consumption (rs=0.716), but with no correlation to the frequency of airing or the basic ventilation rate. Tobacco smoking seems to be the main indoor source of SPM in contemporary dwellings. The importance of these findings is underlined by epidemiologic studies on passive smoking and health. Air quality standards for the ambient air are based on certain risk groups such as infants, children, persons with chronic obstructive lung disorders, and indoor air standards should be based on the same concepts of health protection.  相似文献   

9.
Some twenty nuclear sites are located along the Rhône. A radioecological study of the river has been in progress since 1974 and a brief outline is given here of its hydrological, chemical, sedimentological and biological features. The techniques used for sampling, processing and radioactivity measurement in fish are also described. A summary of the results demonstrates the influence of the nuclear power stations and fuel cycle plants on the evolution of radioactivity levels in fish as a function of time or distance from liquid waste discharge points.Comparison with data for the Meuse shows that at the present time activities in fish downstream of the nuclear power stations are comparable in both rivers. Levels are, however, higher in the Rhône downstream from the Marcoule reprocessing plant. The data collected in situ together with the results of laboratory experiments demonstrate the mechanisms of transfer of radionuclides into the aquatic environment and supply information for the protection of environmental health.  相似文献   

10.
The Jordan River is among the world’s most famous and culturally and historically significant waterways. The lower stretch of the river, however, has been a victim of development in a water scarce region, with current flows less than 5 % of historical levels. Furthermore, as it functions as an international border in a region of conflict, access to the river and its potential as a tourist attraction has been limited. Recently, there have been numerous calls for rehabilitation of the river. This study presents a first estimate of the economic benefits of such rehabilitation and compares them to the estimated costs. Identical contingent valuation method surveys were administered in Israel, Jordan, and the Palestinian Authority. Evidence from this study shows that, despite the large opportunity costs of increasing environmental flows, rehabilitation of the lower Jordan would produce positive net economic benefits. This is true even though the study estimated only the benefits to local populations, and not to international tourists or those outside the region. Net benefits are maximized when taking a regional, as opposed to strictly national, approach.  相似文献   

11.
A global change assessment required detailed simulation of water availability in the Elbe River basin in Central Europe (148,268?km2). Using the spatially semi-distributed, eco-hydrological model SWIM, spatial calibration was applied. For 225 sub-areas covering the model domain (134,890?km2), evapotranspiration and groundwater dynamics were individually adjusted. The calibration aimed at good correspondences with long-term run-off contributions and the hydrographs for two extreme years. Measured run-off was revised from water management effects to produce quasi-natural discharges for calibration. At some gauges, there were large volume differences between these reference data and the simulations of the spatially uncalibrated model. Most affected were some sub-basins in the Czech part of the basin where the density of available climate stations was much lower than the German part. Thus, both erroneous precipitation data and systematic flaws in the evapotranspiration module of SWIM could have caused the differences. In order to identify the major error source and to validate the choice of spatial calibration parameters (evapotranspiration and groundwater dynamic corrections), MCMC analyses were made for three Czech areas. Optional precipitation correction had been considered by a third calibration parameter in the MCMC assessment. In two of the three cases, it can be shown that evapotranspiration corrections are preferable as precipitation errors are negligible. In the third case, where the analyses indicate a substantial error in precipitation data, an interpolation problem of the climate data at the edge of the model domain could be found. Hence, the applied method shows its potential to identify specific sources of uncertainty in hydrological modelling.  相似文献   

12.
Given the strategic situation of the José León de Carranza bridge, which spans the Bay of Cádiz (in the SW of Spain) and carries very heavy motor traffic, together with knowledge of the currents and tidal flows in the zone, we have used a technique of radioactive dating of sediments to study the temporal evolution presented by contamination from lead in the sediment column. This has allowed us to observe the environmental impact, in terms of the concentration of Pb in the sea bed sediments, that has been produced in the zone by the introduction of unleaded gasolines as substitutes for traditional automobile fuels that employ organic forms of tetra methyl lead as an antidetonant agent in the fuel.  相似文献   

13.
An attempt at population analysis of sables in the Ural–Ob region of the species range was made with the use of vast biological material (craniometry, 1909 specimens; ecological structure, 2157 specimens; and coat color, 439169 pelts). Population groups in the region were mainly described on the basis of morphological, geographic, historical, and ecological criteria. Seven spatially separated population groups were found, which were named after the main rivers of their habitats: the Tavda–Konda–Sos'va, Dem'yanka, Salym–Yugan, Agan–Vakh, Kazym–Nazym, Nadym–Kunovat, and Pur–Taz groups. They distinctly differed from one another with respect to cranial measurements, coat color, and some structural demographic parameters. In some cases, morphological differences reached the subspecies level. The data obtained make it possible to revise the pattern of geographic variation within the species range.  相似文献   

14.
The paper explores the concept of ‘sustainable place-making’ and its necessary relationships and opportunities with the emerging, broader and interdisciplinary field of sustainability science. This implies a reconsideration of the new and emerging interrelationships between economy, community and ecology as a basis for active place-making. The paper then examines the new dynamics of place-making with regard to the contested emergence of the bio-economy and the eco-economy, and the principles and place framings that lie behind these competing paradigms of spatial development. The reference point here is agri-food and urban–rural relations; and it is argued that research in these fields is in need of being contextualised critically and normatively within this dynamic, highly contested and place-making context. The analysis also holds important implications for a more critical and engaging sustainability science.  相似文献   

15.
Projections for 20 years of economic growth and change in the structure of the Thai economy were made for 180 sectors using a computable general equilibrium (CGE) model to compare the following four scenarios: (1) standard growth with infinite supply of factors, (2) finite land supply, (3) fixed use of agricultural chemicals, and (4) combined finite land supply with fixed use of agricultural chemicals. The computable projections suggest that the economic cost of hypothetical environmental control in agriculture is small and further weakened by urbanization. The computed structural development points to efficiency improvements specific to sectors to return the economy to balanced growth.  相似文献   

16.
Original data on 14 urban floras in the Ural–Volga region have been analyzed to estimate the effect of the geographic location, topography, climate, size, and age of a city on the species richness of its flora. This parameter in different cities varied from 288 to 973 species, with the proportion of alien species varying from 21 to 41%. Factors of flora richness were estimated by multiple linear regression using principal component estimates obtained by factor analysis of 13 city characteristics as predictors. It has been confirmed that the richness of urban floras depends primarily on the city size, which accounts for greater proportions of variation in the number of native species (56%), the number of alien species (91%), and the total number of species (71%). In addition, variation in the number of native species is determined by terrain elevation (22%), increasing at higher elevations. The proportion of alien species in the urban flora does not depend on the size of the city and is negatively correlated with terrain elevation.  相似文献   

17.
Dendrogeomorphology is a powerful tool to determine past avalanche activity, but whether or not the obtained annually resolved chronologies are sufficiently detailed to infer avalanche–climate relationships (in terms of temporal resolution) remains an open question. In this work, avalanche activity is reconstructed in five paths of the French Alps and crossed with a set of snow and weather variables covering the period 1959–2009 on a monthly and annual (winter) basis. The variables which best explain avalanche activity are highlighted with an original variable selection procedure implemented within a logistic regression framework. The same approach is used for historical chronologies available for the same paths, as well as for the composite tree-ring/historical chronologies. Results suggest that dendrogeomorphic time series allow capturing the relations between snow or climate and avalanche occurrences to a certain extent. Weak links exist with annually resolved snow and weather variables and the different avalanche chronologies. On the contrary, clear statistical relations exist between these and monthly resolved snow and weather variables. In detail, tree rings seem to preferentially record avalanches triggered during cold winter storms with heavy precipitation. Conversely, historical avalanche data seem to contain a majority of events that were released later in the season and during episodes of strong positive temperature anomalies.  相似文献   

18.
Tropical delta regions are at risk of multiple threats including relative sea level rise and human alterations, making them more and more vulnerable to extreme floods, storms, surges, salinity intrusion, and other hazards which could also increase in magnitude and frequency with a changing climate. Given the environmental vulnerability of tropical deltas, understanding the interlinkages between population dynamics and environmental change in these regions is crucial for ensuring efficient policy planning and progress toward social and ecological sustainability. Here, we provide an overview of population trends and dynamics in the Ganges–Brahmaputra, Mekong and Amazon deltas. Using multiple data sources, including census data and Demographic and Health Surveys, a discussion regarding the components of population change is undertaken in the context of environmental factors affecting the demographic landscape of the three delta regions. We find that the demographic trends in all cases are broadly reflective of national trends, although important differences exist within and across the study areas. Moreover, all three delta regions have been experiencing shifts in population structures resulting in aging populations, the latter being most rapid in the Mekong delta. The environmental impacts on the different components of population change are important, and more extensive research is required to effectively quantify the underlying relationships. The paper concludes by discussing selected policy implications in the context of sustainable development of delta regions and beyond.  相似文献   

19.
Regional Environmental Change - Agroecosystems are facing a global challenge amidst a socioecological transition that places them in a dilemma between increasing land-use intensity to meet the...  相似文献   

20.
By using the value–belief–norm theory of environmentalism, this study investigates American and Korean college students’ support for pro-environmental tax policy as a way to address global climate change. The results indicate that environmental concern and the perceived severity of climate change were significant predictors of one's tax policy support. Perceived individual responsibility for addressing climate change mediated the relationship between environmental beliefs (i.e. environmental concern and perceived severity) and tax policy support for Koreans. Such relationship was not observed among Americans. This study also examines whether political ideology functions as a predictor of tax policy support. For Americans, political ideology was a significant factor in predicting one's tax policy support and that it remained significant even after the inclusion of more proximal predictors—environmental concern and perceived severity. For Koreans, however, political ideology was not a significant factor. Theoretical and practical implications are discussed.  相似文献   

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