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41.
Rangelands represent one of the most important natural resources in mountainous regions of northern Nepal. However, a poor understanding of the social dimensions of rangeland use has limited their proper management and sustainable development, which represent major challenges for Nepal's resource managers. Institutional development is thought to be a viable solution to this problem and may ultimately lead to improved rangeland management in Nepal. Based on this hypothesis, a study was conduced in the Rasuwa district of northern Nepal to examine the effectiveness of institutional development at the local and national levels in mitigating the problems facing sustainable rangeland management by using an institutional analysis and development (IAD) framework. The information and data were mainly collected from different stakeholders, farmers, professionals and practitioners using a toolkit of participatory rural appraisal (PRA), workshops and literature review. It can be concluded from this case study that a number of institutional development efforts are needed to promote sustainable rangeland management in this region. First, local herders represent a repository of rich indigenous knowledge essential to sustaining sound rangeland management practices; hence, indigenous practices need to be integrated into modern technologies. Second, public services and technical support are currently unavailable or inaccessible to local herders; hence, research, development and extension interventions need to be initiated for marginalized pastoral communities. Third, rangeland institutions are incomplete and ill-organized, so institutional development of various organizations is necessary for promoting sustainable rangeland management. Fourth, the policies and governance necessary for promoting rangeland management are not well-designed; hence, governance reform and policy development need to be formulated through internal and external agencies and organizations.  相似文献   
42.
A study was carried out to assess the spatial distribution of arsenic in the intertidal sediments of the River Scheldt in Belgium. Sediment samples were collected from different locations along the River Scheldt up to 100 cm depth and analysed for the major physicochemical properties. The study reveals that the arsenic contents in the sediment samples vary in a wide range, from 2.3 to 140.2 mg kg(-1) dry weight. Moreover, the arsenic concentrations are generally below the background concentrations and remediation thresholds of arsenic in Flanders, Belgium. The occurrence of arsenic is found closely related to some physicochemical properties of the sediments. Arsenic has a strong positive correlation with organic matter and clay contents. On the contrary, a negative correlation exists between arsenic, sand and pH. It is recommended to develop and use organic matter control practices for lowering further accumulation of arsenic within the sediments.  相似文献   
43.
To estimate the contribution of transboundary transported air pollutants from other Asian countries to Japan in ionic concentrations in fog water in March 2005, the Community Multiscale Air Quality (CMAQ) modeling system was utilized with meteorological fields produced by the 5th generation Mesoscale Model (MM5). For meteorological predictions, the model well reproduced the surface meteorological variables, particularly temperature and humidity, and generally captured fog occurrence. For chemical predictions, most of the model-predicted monthly mean concentrations were approximately within a factor of 2 of the observations, indicating that the model well simulated the long-range atmospheric transport from the Asian Continent to Japan. For SO42?, NO3? and NH4+, the contribution rates of the transboundary air pollution in the Kinki Region of Japan ranged from 69 to 82% for aerosols, from 47 to 87% for ionic concentrations in rain, and from 55 to 79% for ionic concentrations in fog. The study found that the transboundary air pollution also affected ionic concentrations in fog as well as aerosol concentrations and ionic concentrations in rain.  相似文献   
44.
Risk of flood-related mortality in Nepal   总被引:1,自引:0,他引:1  
In July 1993, severe flooding devastated Sarlahi district in Nepal. The next month, a follow-up study of a large population cohort was undertaken. The study is unique in that a prospective research database was used to verify residency prior to the flood and to confirm vital status afterwards. It evaluated 41,501 children aged between two and nine years and adults aged 15-70 in 7,252 households. Flood-related fatality rates were 13.3 per 1,000 for girls and 9.4 per 1,000 for boys, 6.1 per 1,000 for women and 4.1 per 1,000 for men. Flood-related fatality rates for children were six times higher than mortality rates in the same villages a year before the flood (relative risk (RR) = 5.9, 95 per cent confidence interval (CI) 5.0-6.8). Flood-related fatality was associated with low socio-economic status preflood (RR = 6.4, 95 per cent CI 2.7-20.0), and having a house constructed of thatch (RR = 5.1, 95 per cent CI 1.7-24.5).  相似文献   
45.
46.
GIS overlay techniques were used to provide a quantitative historic documentation of deforestation and land-use dynamics in the Middle Mountains of Nepal between 1947 and 1990. Deforestation was most critical in the 1960s, but active afforestation programs in the 1980s have reversed the process. In spite of these trends, the degradation problem is more complex. The GIS evaluation showed that 86% of the recently afforested land is now under pine plantations located primarily at lower elevations and moderately steep slopes. In contrast, rainfed agricultural expansion is most pronounced on acidic soils and steeper, upper elevation sites, suggesting marginalization of agriculture. Agricultural expansion coupled with major losses of grazing land to pine forests are the key processes pointing towards major animal feed deficits. An alternative animal feed source is suggested through GIS using a topographically based microclimatic classification to generate a tree-planting map where the optimum ecological conditions for selective native fodder tree species are identified.  相似文献   
47.
Shrestha, Rajesh R., Yonas B. Dibike, and Terry D. Prowse, 2011. Modeling Climate Change Impacts on Hydrology and Nutrient Loading in the Upper Assiniboine Catchment. Journal of the American Water Resources Association (JAWRA) 48(1): 74‐89. DOI: 10.1111/j.1752‐1688.2011.00592.x Abstract: This paper presents a modeling study on climate‐induced changes in hydrologic and nutrient fluxes in the Upper Assiniboine catchment, located in the Lake Winnipeg watershed. The hydrologic and agricultural chemical yield model, Soil and Water Assessment Tool (SWAT) was employed to model a 21‐year baseline (1980‐2000) and future (2042‐2062) periods with model forcings for future climates derived from three regional climate models (RCMs) and their ensemble means. The modeled future scenarios reveal that potential future changes in the climatic regime are likely to modify considerably hydrologic and nutrient fluxes. The effects of future changes in climatic variables, especially precipitation and temperature, are clearly evident in the resulting snowmelt and runoff regimes. The future hydrologic scenarios consistently show earlier onsets of spring snowmelt and discharge peaks, and higher total runoff volumes. The simulated nutrient loads closely match the dynamics of the future runoff for both nitrogen and phosphorus, in terms of earlier timing of peak loads and higher total loads. However, nutrient concentrations could decrease due to the higher rate of runoff increase. Overall, the effects of these changes on the nutrient transport regime need to be considered together with possible future changes in land use, crop type, fertilizer application, and transformation processes in the receiving water bodies.  相似文献   
48.
Aliphatic–aromatic polyols were synthesized by thiol–ene reactions (photochemical or thermal) using mercaptanized starting materials from bio-based compounds: limonene dimercaptan, thioglycerol, mercaptanized castor oil and isosorbide (3-mercaptopropyl) ether. Aromatic starting materials were phenols containing double bonds; ortho-allyl phenol (OAP, petrochemical-based) and eugenol (EUG, bio-based). The phenolic hydroxyl groups were blocked by alkoxylation with propylene oxide (PO) or glycidol (GLY) prior to use in thiol–ene reaction. The aromatic rings were attached to the mercaptans by reacting thiol groups with the double bonds of alkoxylated OAP (OAP–PO and OAP–GLY) and alkoxylated EUG (EUG–PO and EUG–GLY). These synthesized aliphatic–aromatic polyols were utilized for preparation of rigid polyurethane foams whose physical–mechanical properties were superior to those made only from bio-based aliphatic polyols. These rigid PU foams can be used in a wide range of applications; such as thermal insulation of freezers, buildings, pipes and storage tanks for food and chemical industries, as wood substitute, packaging materials and flotation materials.  相似文献   
49.
Mercury is a heavy metal which has garnered attention recently in India. Minamata Convention on mercury was established on October 2013 and was joined by India on September 30, 2014. India is seen as a major mercury pollution source after China according to many studies in the past. Various mercury pollution sites that are currently recognized in India are Kodai Lake, Kodaikanal, Tamil Nadu, and Thane Creek, Mumbai. Since 1992, chlor-alkali plants have been regulated to eliminate mercury cell process of manufacturing. Also, medical and health care facilities are discarding mercury-containing equipment and processes. Various anthropogenic sources of mercury to the atmosphere include combustion of fossil fuels, processing and mining of primary metal ores, cement manufacturing units, chlor-alkali plants, and use of mercury in various products like paints, electric switches, and relays. The hazard associated with mercury pollution becomes extremely serious when we consider its ability to be transported over long-range distances. Various atmospheric transport models suggest India and other Asian countries to be a major source of long-range transport of mercury to North America. Considering the hazards of mercury and its widespread presence in our life, a study on mercury pollution in an urban water body is conducted. This study deals with Mithi River located in Mumbai Metropolitan Region (19.0760° N, 72.8777° E) to study the total mercury in water and derive its relationship with other pollution parameters.  相似文献   
50.
The Clean Development Mechanism (CDM) under the Kyoto Protocol to the United Nations Framework Convention on Climate Change is considered a key instrument to encourage developing countries' participation in the mitigation of global climate change. Reduction of greenhouse gas (GHG) emissions through the energy supply and demand side activities are the main options to be implemented under the CDM. This paper analyses the general equilibrium effects of a supply side GHG mitigation option-the substitution of thermal power with hydropower--in Thailand under the CDM. A static multi-sector general equilibrium model has been developed for the purpose of this study. The key finding of the study is that the substitution of electricity generation from thermal power plants with that from hydropower plants would increase economic welfare in Thailand. The supply side option would, however, adversely affect the gross domestic product (GDP) and the trade balance. The percentage changes in economic welfare, GDP and trade balance increase with the level of substitution and the price of certified emission reduction (CER) units.  相似文献   
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