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391.
    
This paper focuses on efforts to produce an operational definition of the concept of ‘sustainable development’ as articulated by the 1992 United Nations Conference on Environment and Development (UNCED). ‘Sustainability’ has become an increasingly significant environmental issue; the problems in articulating a workable concept will differ among nations and international organizations attempting to define the term. Additionally, the term encompasses the varied fields of ecology, philosophy, and economics; every discipline imparts its own bias. Various definitions are provided and the significance and difficulty of developing an operational definition of Sustainable development is discussed. For example, sustainable development has become a ‘needs'-oriented term, an entitlement that priority should be given to the needs of the world's poor. Some argue that living standards which go beyond the basic minimum are sustainable only if consumption standards everywhere have regard for long-term sustainability. Scientifically, sustainability involves replicability and regeneration through an unforeseeable future. When prices reflect social cost and there are no externalities, optimal choices will be made between present and future consumption. Much of the debate involving sustainability involves deep-rooted fears or phobias, e.g. resource depletion, ‘energy crises’ and ‘timber crises’.  相似文献   
392.
    
Investments in energy efficiency entail uncertainty, and when faced with uncertainty consumers have been shown to behave according to prospect theory: preferences are reference-dependent and exhibit loss aversion, and probabilities are subjectively weighted. Using data from a choice experiment eliciting prospect theory parameters, I provide evidence that loss-averse people are less likely to invest in energy efficiency. Then, I consider policy design under prospect theory when there are also externalities from energy use. A higher degree of loss aversion implies a higher subsidy to energy efficiency. Numerical simulations suggest that the impact of prospect theory on policy may be substantial.  相似文献   
393.
A model describing parents’ preferences to relieve their own and their children's acute illnesses is estimated using stated-preference data. Estimated marginal rates of substitution (MRS) between child and parent illness are about two, indicating that parents value children's illness attributes twice as highly as their own. The MRS is larger for younger children, falls toward unity as the child approaches adulthood, and appears to reflect parental altruism rather than parent–child differences in initial health or illness costs. Intra-family allocations may compensate for chronic health impairments. Parents’ willingness to pay to avoid own or child illness increases with income, declines with fertility, increases at a decreasing rate with duration and number of symptoms, and depends on perceived discomfort and activity restrictions. Current methods of assessing morbidity benefits of environmental regulations may understate substantially the value of children's health, particularly in African-American families.  相似文献   
394.
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Ecological systems often operate on time scales significantly longer or shorter than the time scales typical of human decision making, which causes substantial difficulty for conservation and management in socioecological systems. For example, invasive species may move faster than humans can diagnose problems and initiate solutions, and climate systems may exhibit long‐term inertia and short‐term fluctuations that obscure learning about the efficacy of management efforts in many ecological systems. We adopted a management‐decision framework that distinguishes decision makers within public institutions from individual actors within the social system, calls attention to the ways socioecological systems respond to decision makers’ actions, and notes institutional learning that accrues from observing these responses. We used this framework, along with insights from bedeviling conservation problems, to create a typology that identifies problematic time‐scale mismatches occurring between individual decision makers in public institutions and between individual actors in the social or ecological system. We also considered solutions that involve modifying human perception and behavior at the individual level as a means of resolving these problematic mismatches. The potential solutions are derived from the behavioral economics and psychology literature on temporal challenges in decision making, such as the human tendency to discount future outcomes at irrationally high rates. These solutions range from framing environmental decisions to enhance the salience of long‐term consequences, to using structured decision processes that make time scales of actions and consequences more explicit, to structural solutions aimed at altering the consequences of short‐sighted behavior to make it less appealing. Additional application of these tools and long‐term evaluation measures that assess not just behavioral changes but also associated changes in ecological systems are needed.  相似文献   
395.
Abstract: The last century has seen the ascendance of a core economic model, which we will refer to as Walrasian economics. This model is driven by the psychological assumptions that humans act only in a self‐referential and narrowly rational way and that production can be described as a self‐contained circular flow between firms and households. These assumptions have critical implications for the way economics is used to inform conservation biology. Yet the Walrasian model is inconsistent with a large body of empirical evidence about actual human behavior, and it violates a number of basic physical laws. Research in behavioral science and neuroscience shows that humans are uniquely social animals and not self‐centered rational economic beings. Economic production is subject to physical laws including the laws of thermodynamics and mass balance. In addition, some contemporary economic theory, spurred by exciting new research in human behavior and a wealth of data about the negative global impact of the human economy on natural systems, is moving toward a world view that places consumption and production squarely in its behavioral and biophysical context. We argue that abandoning the straightjacket of the Walrasian core is essential to further progress in understanding the complex, coupled interactions between the human economy and the natural world. We call for a new framework for economic theory and policy that is consistent with observed human behavior, recognizes the complex and frequently irreversible interaction between human and natural systems, and directly confronts the cumulative negative effects of the human economy on the Earth's life support systems. Biophysical economics and ecological economics are two emerging economic frameworks in this movement.  相似文献   
396.
Herein we develop a means to differentiate between the energy required to expand and the energy required to maintain the economies of cities. A nonlinear model is tested against historical data for two cities, Hong Kong and Singapore. A robust fit is obtained for Hong Kong, with energy for maintenance close to that for growth, while Singapore, with a weaker fit, is growth dominated. The findings suggest that decreases in either of the per unit maintenance or growth demands can simultaneously cause gross domestic product (GDP) and total energy use to increase. Furthermore, increasing maintenance demands can significantly limit growth in energy demand and GDP. Thus, the low maintenance demands for Hong Kong, and especially Singapore, imply that, all other things being equal, GDP and energy use of these cities will continue to grow, though Singapore’s higher energy use for growth means it will require more energy than Hong Kong.  相似文献   
397.
Firms would like to capitalize on consumers' willingness to pay more for goods that use environmentally friendly production techniques, but have difficulty credibly conveying their environmental friendliness. One possible remedy is “ecolabeling,” where a third party certifies firms' products. To model this phenomenon, I analyzed a market characterized by asymmetric information in which firms decide whether to seek an ecolabel. Market equilibrium is discussed in three settings: where both technologies and outputs are fixed (so the only choice is whether to seek certification), where technologies are fixed but outputs are not, and where firms can choose both technology and output.  相似文献   
398.
应用\"污染贡献率\"这一指标,分析了\"三河三湖\"流域COD和氨氮排放的重污染行业以及地区分布,指出了各流域COD和氨氮排放的控制重点.同时分析了各流域重污染行业的\"经济贡献率\",最后结合行业的污染贡献率和经济贡献率以及行业在地区所占的比例,提出了几点重要的结论.  相似文献   
399.
In the arid regions of Tunisia, considerable investments are being made to maintain the old water harvesting techniques and introduce new ones to capture the scarce amount of rainwater (100 mm to 230 mm annually) for agricultural and domestic purposes. However, no detailed assessment of the multiple effects and the costs and benefits of these techniques have been made so far. This paper summarizes the results of an in depth investigation of the multiple impacts (runoff mobilization, ground water recharge, agro-socio-economic impacts) of the water harvesting works undertaken in the watershed of oued Oum Zessar (southeastern Tunisia). The importance of interdisciplinary and integrated approaches was revealed through this detailed impact assessment and economic evaluation. In fact, the profitability of the water harvesting works depends largely on the criteria chosen. However, further refinements are needed to better include all possible impacts (positive and negative) that occur as a result of the installation of the water harvesting structures.  相似文献   
400.
Based on the theory of ecological footprint this paper analyzed the ecological economic system in Funing County in the view of demands of economic system to natural resource and supply of ecosystem for natural resources. It was proposed that the concept of ecological deficit (ecological remainder) per ten thousands yuan GDP be used to evaluate development of ecological economic system. With a synthesis appraisement to the ecological economic system using entire-array-polygon method combined with Ulanowicz development ability and with ecological deficit (ecological remainder) per ten thousands yuan GDP, it provids a theoretical base for reconstructing and managing of demonstration eco-region.  相似文献   
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