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631.
This paper develops a multi-country multi-sector general equilibrium model, integrating high-frequency electricity dispatch and trade decisions, to study the effects of electricity transmission infrastructure (TI) expansion and renewable energy (RE) penetration in Europe for gains from trade and carbon dioxide emissions in the power sector. TI can benefit or degrade environmental outcomes, depending on RE penetration: it complements emissions abatement by mitigating dispatch problems associated with volatile and spatially dispersed RE but also promotes higher average generation from low-cost coal if RE production is too low. Against the backdrop of European decarbonization and planned TI expansion, we find that emissions increase for current and targeted year-2020 levels of RE production and decrease for year-2030 targets. Enhanced TI yields sizeable gains from trade that depend positively on RE penetration, without creating large adverse impacts on regional equity.  相似文献   
632.
苏州市生活垃圾处理碳足迹核查   总被引:2,自引:1,他引:1  
根据《PAS2050规范》的指导,结合生命周期评价技术方法和LandGEM模型,对苏州市生活垃圾填埋和焚烧处理的生命周期过程进行了碳足迹核查. 详细列出了垃圾处理过程中可能的温室气体排放源,计算各排放源的电耗或能耗,并通过与温室气体排放系数相乘最终转化为苏州市生活垃圾处理温室气体排放量. 结果表明:苏州市填埋处理1 t生活垃圾整个生命周期过程中温室气体的排放量(以CO2当量计)为1 942.47 kg,焚烧处理为-180.87 kg. 按照目前苏州市生活垃圾处理权重进行分配,可得苏州市处理1 t生活垃圾整个生命周期过程中温室气体的排放量(以CO2当量计)为880.80 kg. 在整个核查过程中,考虑了在填埋和焚烧处理时发电对温室气体带来的减量效应.   相似文献   
633.
This paper provides a first analysis of a “policy bloc” of fossil fuel importers which implements an optimal climate policy, faces a (non-policy) fringe of other fuel importers, and an exporter bloc, and purchases offset from the fringe. We compare a carbon tax and a cap-and-trade scheme for the policy bloc, in either case accompanied by an efficient offset mechanism for reducing emissions in the fringe. The policy bloc is shown to prefer a tax over a cap, since only a tax reduces the fuel export price and by more when the policy bloc is larger. Offsets are also more favorable to the policy bloc under a tax than under a cap. The optimal offset price under a carbon tax is below the tax rate, while under a cap and free quota trading the offset price must equal the quota price. The domestic carbon and offset prices are both higher under a tax than under a cap when the policy bloc is small. When the policy bloc is larger, the offset price can be higher under a cap. Fringe countries gain by mitigation in the policy bloc, more under a carbon tax since the fuel import price is lower.  相似文献   
634.
The quantity and biochemical composition of organic matter (OM) in the sediments underlying and below oxygen minimum zone (OMZ) in the Arabian Sea were studied to provide information on the diagenetic processes of organic carbon under different environmental conditions. Concentrations of total organic carbon (TOC), total nitrogen (TN) and total hydrolysable amino acids (THAA) were significantly higher in sediments within rather than below OMZ, while those of total carbohydrates (TCHO) were slightly lower in the latter, suggesting the presence of a larger supply of labile compounds into the sea bottom at the shallower site (i.e. within OMZ). Hydrolysable amino acid and carbohydrate contribution to TOC were even lower (about 10% in surficial sediments) than the values obtained from the abyssal oligotrophic North Pacific, suggesting that OM food availability in the Oman Margin sediments within OMZ was lower than that observed at abyssal depths. The presence of the highest THAA and TCHO concentrations in the top 40?mm of the sediment core at both sites reflected the presence of bioturbation processes. In contrast with the general view of the deep sea as a stable and constant system, below OMZ in the Arabian Sea sediments, some differences were observed in the two investigated cores indicating the presence of a certain spatial variability in OM content and diagenesis.  相似文献   
635.
Studying eco-sustainability of tourism areas is part of sustainable development research. In tourism areas, the ecosystem comprises both the environment and the human system. The environmental system is basically physical, whereas the human system, consisting of both tourists and residents, is the dominant factor driving ecosystem change. If the combined influence of tourists and residents exceeds the carrying capacity of the environment, which is the ecological threshold of eco-sustainability in the tourism area, then the structure, function and stability of the environment will degenerate. Hence, eco-sustainability assessment of tourism areas should be based on analyses of the relationship between the influence of tourists and residents on the environment and the environmental carrying capacity. Using ecological footprint and tourism ecological footprint models, we developed and applied a synthetic assessment index system for eco-sustainability of tourism areas in Lijiang County, Yunnan Province, China, to conduct a quantitative spatial assessment for 2001. The eco-sustainability of Lijiang was high, with a harmonious relationship between regional socioeconomic development and the ecological environment. There were significant spatial differences in eco-sustainability among 24 towns in the region because of spatial heterogeneity in socioeconomic status, tourism development and environmental elements.  相似文献   
636.
Summary

The Ecological Footprint (EF) is a method for estimating the biologically productive area necessary to support current consumption patterns, given prevailing technical and economic processes. By comparing human impact with the planet's limited bioproductive area. this method tests a basic ecological condition for sustainability. The ecological footprint has gained popularity for its pedagogical strength as it expresses the results of its analysis in spatial units that can easily be communicated. Many EF estimates have been performed on a global, national and sulrnationallevel. In this paper. we review the method and critically assess it from a sustainability perspective based on first order principles. We examine: ? Which aspects of sustainability are already covered by existing EF assessments;

? Which further aspects ofsustainability could be made accountable through the EF (such as areas needed to assimilate waste streams that are not yet accounted for in present assessments); and

? Those aspects ofsustainability that cannot be accountable through the EF. Thereby needing complimentary auditing tools.

Since the EF is a measure of renewable biocapacity, we argue that some dimensions of ecological sustainability should not be included in the EF. These include human activities that should be phased out to obtain sustainability, such as emissions of persistent compounds foreign to nature and qualitative aspects that represent secondary uses of ecological areas and do not, therefore, occupy a clearly identifiable additional ecological space. We also conclude that the EF is useful for documenting the overall human use or abuse of the potentially renewable functions and services of nature. Particularly, by aggregating in a consistentway a varity of human impacts, it can effectively identify the scale of the human economy by companson with the size of the biosphere.  相似文献   
637.
基于基尼系数的中国灰水足迹区域与结构均衡性分析   总被引:4,自引:1,他引:3  
孙才志  白天骄  韩琴 《自然资源学报》2016,31(12):2047-2059
论文在对中国大陆31个省市1998-2013年各类来源的灰水足迹进行测算的基础上,选取人口、GDP两个指标,应用基尼系数对中国1998-2013年灰水足迹的空间、结构均衡性情况进行了研究。结果显示:1)在区域均衡性方面,经济灰水足迹均衡性较差,东部与西部地区分别在经济灰水足迹和人口灰水足迹中的均衡性较低;2)在结构均衡性方面,经济灰水足迹均衡性已达到“差距偏大”范围,其中农业和工业的均衡性较差,生活经济灰水足迹均衡性近年来降幅明显;3)从边际效应来看,可以通过减少中、西部重污染地区灰水足迹及各省市农业灰水足迹的方式提升整体均衡性,有效促进中国水环境公平性的提升。最后,针对中国灰水足迹均衡性的具体问题,提出了减少中国灰水足迹、提升水环境公平性的相关建议。  相似文献   
638.
Functionalized Granular Activated Carbons (FACs) are used as adsorbents for treating pharmaceutical wastewaters containing Chlorhexidine Gluconate. Chemical modifications of Granular Activated Carbons (GACs) using functionalizing agents like HCl and HF produce FACs. The adsorption capacity of each of FAC-HCl and FAC-HF is found to be higher than GAC. The modelled maximum adsorption capacity for FAC-HCl is 1.02 g/g of adsorbent, 3.49 g/g of adsorbent for FAC-HF and 0.0682 g/g of adsorbent for GAC. This is mainly due to the additional chemisorptions by surface complexation at the functionalized surface sites of the modified GACs. This is also supported by the well-known pseudo-second-order kinetic model. Formation of surface complexes with the functional groups and weakly polar Chlorhexidine Gluconate is well supported by the physical characterization using Energy dispersive X-ray spectroscopy (EDAX), Brunner–Emmett–Teller (BET) test and Fourier Transform Infrared spectroscopy (FTIR) analysis after adsorption. The adsorption capacity of GAC and the FACs increases in the order of FAC-HF > FAC-HCl > GAC conforming to the proportion of the total acidity of the carbon surfaces. Intra-particle diffusion is not the sole rate-controlling factor. An agreement to pseudo-second-order kinetic model, Elovich kinetic model and Boyd's film diffusion model proves that chemisorption is the rate-controlling parameter in this adsorption study.  相似文献   
639.
This paper develops an integrated model of the fuel and agricultural sectors to analyze the welfare and greenhouse gas emission (GHG) effects of the existing Renewable Fuel Standard (RFS), a Low Carbon Fuel Standard (LCFS) and a carbon price policy. The conceptual framework shows that these policies differ in the incentives they create for the consumption and mix of different types of biofuels and in their effects on food and fuel prices and GHG emissions. We also simulate the welfare and GHG effects of these three policies which are normalized to achieve the same level of US GHG emissions. By promoting greater production of food-crop based biofuels, the RFS is found to lead to a larger reduction in fossil fuel use but also a larger increase in food prices and a smaller reduction in global GHG emissions compared to the LCFS and carbon tax. All three policies increase US social welfare compared to a no-biofuel baseline scenario due to improved terms-of-trade, even when environmental benefits are excluded; global social welfare increases with a carbon tax but decreases with the RFS and LCFS due to the efficiency costs imposed by these policies, even after including the benefits of mitigating GHG emissions.  相似文献   
640.
方恺 《生态环境》2014,(11):1868-1875
足迹家族和行星边界都是国际可持续发展研究领域新近出现的热点概念。系统回顾了足迹家族和行星边界的概念缘起,首次提出了基于足迹家族和行星边界的环境可持续性概念及其评价框架。其中,足迹家族定义为:人类在自然资源消费和废弃物排放过程中占用的地球生态系统的再生和消纳能力;行星边界定义为:可供人类安全占用的地球生态系统的最大再生和消纳能力。由此,将环境可持续性定量描述为人类环境足迹小于或等于对应行星边界的情形,反之则为环境不可持续性。分析了该环境可持续性概念的6项基本特征:系统性、选择性、交互性、不确定性、尺度依赖性、赤字可权衡性。在此基础上,以全球30个主要国家为例,对提出的足迹家族-行星边界整合框架进行了实证应用。从与人类社会关系重大的环境问题入手,对各国在气候变化(碳排放)、水资源利用和土地利用3方面的环境可持续性进行了多维测度。结果显示:22国的碳排放呈现不可持续性,人均碳赤字最高为美国的26.1 t·a-1(以CO2当量计);17国的水资源利用呈现不可持续性,人均水赤字最高为西班牙的1497.8 m3·a-1;15国的土地利用呈现不可持续性,人均土地赤字最高为荷兰的2.3 hm2·a-1。研究表明,碳排放的可持续性与社会经济发展水平关系密切,发达国家对气候变化的贡献明显大于发展中国家;水资源利用和土地利用的可持续性则更多地受各国人均资源禀赋制约。本研究对科学量化和比较不同国家的环境可持续性具有参考价值,该评价方法也适用于其他环境问题或国家以下尺度的核算分析。  相似文献   
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