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991.
This article analyses the application of voluntary environmental agreements (VEAs) in watershed protection in Costa Rica. Next to an involvement of private energy firms, the Costa Rican state, and farmers, the participation of NGOs is a remarkable feature. From an analysis of these multi-stakeholder arrangements, it is concluded that these arrangements bring benefits to all actors involved. VEAs have been able to grow as powerful policy instruments, generating positive environmental effects. Essential is their embedded ness in a broader set of environmental policies, especially related to forest management Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue.  相似文献   
992.
Pinus roxburghii (chir-pine) and Quercus leucothchophora (banj-oak) are dominant forests of mountainous part of the Uttarakhand Himalaya. The continued anthropogenic disturbance is opening the canopy, forming canopy gaps and as a result forest fragments are developing. Thus, the present study aims to analyze variations in species richness and vegetational parameters in relation to canopy gaps in forests. Total species richness was greater in open canopied forest compared to moderate and close canopied forests. In comparison between oak and pine forest, it was greater in oak forest while the proportion of common species was low between oak—pine forests. Mean species richness did not significantly vary from one canopy gap to another as well as in oak and pine dominated forest. This indicated that dominant forest types played an important role to form the community structure. The shrubs richness were greater in closed canopy and between the forests it was greater in pine forest. Tree and shrub density was low in open canopy while herb density was high in moderate canopy. Thus, this study indicated that the dominant canopy species play an important role in deciding the community structures especially the distribution of under canopy species. These parameters should be considered for conservation and maintenance of plant biodiversity of a region.  相似文献   
993.
There is much discussion within the sustainable development community regarding climate stabilization and particularly, finding environmentally equitable ways to address emission reductions. Knowing the current level of emission is only one variable in this complex picture. While the rate of emissions is clearly a problem, the overall increase in GHG concentration in the atmosphere is ultimately the main driver of anthropogenic warming. Therefore, it is also important to understand the cumulative emissions, those which have taken us to the current condition. This research presents a case study of six countries to compare the emissions per capita and cumulative emissions during the past 200 years. It is known that carbon emissions are closely related to economic activities, but here we show that some countries have reached per capita emissions plateaus at different levels while others are still rising. Specifically, one approach toward socioeconomic development, in terms of energy–economy, reaches a plateau at 10 Mt carbon per person, which the United Kingdom and South Korea have attained. The US occupies another emission regime at 20 Mt carbon per person. Developing economies such as India and China are considerably below these levels, and unless they follow other integrated economic/environmental solutions, they will continue to increase their per capita emissions during development.  相似文献   
994.
This study focuses on analyses of greenhouse gas (GHG) emission reductions, from the perspective of interrelationships among time points and countries, in order to seek effective reductions. We assessed GHG emission reduction potentials and costs in 2020 and 2030 by country and sector, using a GHG emission reduction-assessment model of high resolution regarding region and technology, and of high consistency with intertemporal, interregional, and intersectoral relationships. Global GHG emission reduction potentials relative to baseline emissions in 2020 are 8.4, 14.7, and 18.9 GtCO2eq. at costs below 20, 50, and 100 $/tCO2eq., corresponding to +19, −2, and −7 %, respectively, relative to 2005. The emission reduction potential for 2030 is greater than that for 2020, mainly because many energy supply and energy-intensive technologies have long lifetimes and more of the current key facilities will be extant in 2020 than in 2030. The emission reduction potentials in 2030 are 12.6, 22.0, and 26.6 GtCO2eq. at costs below 20, 50, and 100 $/tCO2eq., corresponding to +19, −2, and −7 %, respectively, relative to 2005. The emission reduction potential for 2030 is greater than that for 2020, mainly because many energy supply and energy-intensive technologies have long lifetimes and more of the current key facilities will be extant in 2020 than in 2030. The emission reduction potentials in 2030 are 12.6, 22.0, and 26.6 GtCO2eq. at costs below 20, 50, and 100 /tCO2eq., corresponding to +33, +8, and −3 %, respectively, relative to 2005. Global emission reduction potentials at a cost below 50 $/tCO2eq. for nuclear power and carbon capture and storage are 2.3 and 2.2 GtCO2eq., respectively, relative to baseline emissions in 2030. Longer-term perspectives on GHG emission reductions toward 2030 will yield more cost-effective reduction scenarios for 2020 as well.  相似文献   
995.
In order to determine the potential for sustainable regional development of the Caspian coastal zone, a study was made for the Khachmaz–Absheron zone of Azerbaijan. An evaluation was performed to assess the anthropogenic load on landscapes. Using the 8-point scale offered by Isachenko [2001, Ecological Geography of Russia, Saint Petersburg University Press, Saint Petersburg] for the indicators of agricultural, industrial, urban and integral anthropogenic loads, we did a preliminary ranking of the provinces in the Khachmaz–Absheron zone of Azerbaijan for the each indicator taken separately. Vital statistics were used as a supplementary indicator of environmental conditions in the region. By comparing the data for provinces with each other and the data on Azerbaijan average, we have classified the provinces into 4 groups according to specific combinations of the indicators. Each group of provinces has distinctive environmental conditions and features for sustainable development. The classification makes it possible to develop certain recommendations for the regional sustainable development. Measures to be implemented within the Azerbaijan State Program on Social and Economic Development of Regions are also discussed. In the Khachmaz province, production of ecologically pure products is highly recommended. Special attention should be given to the development of tourism and recreational institutions in the Khachmaz, Khizi and Devechi provinces. Recommendations for these provinces include further development of industry on the basis of modern safe technologies. The irrigation and drainage networks should be reconstructed. The reconstruction will make it possible to reduce water loss and to increase the productivity of agriculture. In the Absheron province, Baku and Sumgait cities environmental systems are overloaded, and so the works at highly polluting enterprises must be stopped, the enterprises have to be re-equipped (old filters must be changed first of all) or relocated from the area (a decrease of environmental risk should be in the focus of attention). For improving of air quality, green areas should increase. There is a need to reduce urban traffic density and to reconstruct highways. Use of old vehicles must be forbidden or restricted, and transition to environmentally friendly fuel should be supported in every way possible. It is necessary to bring the waste management system and sanitary landfills up to international standards, and to improve the water supply and sewerage systems.  相似文献   
996.
Human society consumes resources that it is not able to reproduce. Human activities are still based on “open cycles,” starting from a condition of natural environmental balance and reaching an environmental imbalance. The challenging scope of scientific and technological research towards sustainability appears clear if it is based on this analysis: to find development systems based on “closed cycles” of resources. The challenging objective of realizing closed cycles leads to a definition of sustainability that indicates the path to sustainable development, as well as stating the general principle. It also provides a key to the qualitative measurement of sustainability. This means that the sustainability level of a system can be measured by measuring its capacity to avoid the consumption of resources. Zero consumption is a necessary condition for sustainability, and brings about as a side effect the highly desired “zero-waste” result. Materials entering the proposed endless scheme pass through the process of usefulness without losing their capacity to feed the system again after being used. Thus, the concept of “consumption” itself is replaced by one of “use” when resources are inserted into closed loops capable of feeding human development. The application of the closed cycle sustainability criterion particularly displays its feasibility, and a theoretical guiding role, in the energy sector. Energy vectors such as hydrogen and electricity enable the closure of the energy resources loop by effectively approaching the objective of “zero consumption” (and the side result of “zero waste”) through already demonstrated technological solutions.  相似文献   
997.
998.
This paper recommends a revision of watershed development policy in India in relation to the planning of development interventions involving agricultural intensification and rainwater harvesting following biophysical and societal impact studies carried out on two watershed development projects in Karnataka. A need for changes in policy has arisen in response to progressive catchments closure at the basin level and declining volumes of water flowing into village level reservoirs (known locally as tanks). Flow reductions have occurred largely as a result of increased agricultural intensification over the past 10–15 years. Field levelling, field bund construction, soil water conservation measures, farm ponds, the increase in areas under horticulture and forestry and the increased abstraction and use of groundwater for irrigation are all contributing factors to reduced flows. Planning methodologies and approaches, which may have been appropriate 20 years ago for planning water harvesting within watershed development projects, are no longer appropriate today. New planning approaches are required which (1) take account of these changed flow conditions and (2) are also able to take account of externalities, which occur when actions of some affect the livelihoods of others who have no control or influence over such activities and which (3) contribute to the maintenance of agreed minimum downstream flows for environmental and other purposes.
Ian CalderEmail:
  相似文献   
999.
Industrial society will move towards collapse if its total environmental impact (I), expressed either in terms of energy and materials use or in terms of pollution, increases with time, i.e., dI/dt > 0. The traditional interpretation of the I = PAT equation reflects the optimistic belief that technological innovation, particularly improvements in eco-efficiency, will significantly reduce the technology (T) factor, and thereby result in a corresponding decline in impact (I). Unfortunately, this interpretation of the I = PAT equation ignores the effects of technological change on the other two factors: population (P) and per capita affluence (A). A more heuristic formulation of this equation is I = P(T)·A(T)·T in which the dependence of P and A on T is apparent. From historical evidence, it is clear that technological revolutions (tool-making, agricultural, and industrial) have been the primary driving forces behind successive population explosions, and that modern communication and transportation technologies have been employed to transform a large proportion of the world’s inhabitants into consumers of material- and energy-intensive products and services. In addition, factor analysis from neoclassical growth theory and the rebound effect provide evidence that science and technology have played a key role in contributing to rising living standards. While technological change has thus contributed to significant increases in both P and A, it has at the same time brought about considerable eco-efficiency improvements. Unfortunately, reductions in the T-factor have generally not been sufficiently rapid to compensate for the simultaneous increases in both P and A. As a result, total impact, in terms of energy production, mineral extraction, land-use and CO2 emissions, has in most cases increased with time, indicating that industrial society is nevertheless moving towards collapse. The belief that continued and even accelerated scientific research and technological innovation will automatically result in sustainability and avert collapse is at best mistaken. Innovations in science and technology will be necessary but alone will be insufficient for sustainability. Consequently, what is most needed are specific policies designed to decrease total impact, such as (a) halting population growth via effective population stabilization plans and better access to birth control methods, (b) reducing total matter-energy throughput and pollution by removing perverse subsidies, imposing regulations that limit waste discharges and the depletion of non-renewable resources, and implementing ecological tax reform, and (c) moving towards a steady-state economy in which per-capita affluence is stabilized at lower levels by replacing wasteful conspicuous material consumption with social alternatives known to enhance subjective well-being. While science and technology must play an important role in the implementation of these policies, none will be enacted without a fundamental change in society’s dominant values of growth and exploitation. Thus, value change is the most important prerequisite for avoiding global collapse.
Michael H. HuesemannEmail:
  相似文献   
1000.
The Kyoto Protocol relies on incentive-based regulations layered underneath a global cap on net emissions of greenhouse gases. Within the Kyoto Protocol are opportunities and constraints for signatory nations. Of concern to developing nations are the constraints the Kyoto Protocol could place on future growth. We examine the constraints and the opportunities offered to developing countries within the Kyoto Protocol. By identifying the potential costs and benefits the Kyoto Protocol has to offer to developing countries and by examining the incentives each create, we hope to spark serious investigations into ways to minimize the potential costs of entering the Kyoto Protocol and take full advantage of the potential benefits.
Amin SarkarEmail:
  相似文献   
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