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601.
准确评估种养一体化奶牛场的经济性能与环境绩效,是相关支持政策制定的基础,也是促进奶业低碳生产的关键.本文基于生命周期视角,对非种养一体化奶牛场(non-IPBS)和种养一体化奶牛场(IPBS)养殖过程中的温室气体排放、能源消耗、水消耗、土地占用等环境成本和经济效益进行评估.结果表明,non-IPBS生产1t标准牛奶(FPCM)的净收益为1427元,而IPBS的实际净收益提高7%,如果青贮玉米自给率从当前的32%提升到100%,则实际净收益将提高19%,同时,该净收益的提高率取决于耕地流转费用,临界点为14695元/hm2;相比non-IPBS,IPBS生产1tFPCM的温室气体排放、能源消耗、水消耗、土地占用分别减少6%、6%、5%、7%,如果青贮玉米自给率提升到100%,则相应减少16%、16%、11%、14%.IPBS在降低青贮玉米种植的化肥施用、解决养殖场粪便污染等方面优势明显,在提升养殖经济效益、降低温室气体排放等方面具有巨大潜力,值得推广.  相似文献   
602.
Abstract

This study explained the importance of environmental protection in tourism development and illustrated the relationship between recreational resource valuation and environmental consideration. We compare different models of travel cost method and reiterates long-time existing problems of multi-destination and treats of time opportunity cost (TOC). Taking Jiayuguan’s cultural sights as an example, we establish an updated method called multidestination zonal tourism cost method to evaluate the recreational values (RVs) of selected three cultural sights. We divide trip packages of Jiayuguan’s tourists into 11 portfolios. Each portfolio can be seen as a separate commodity, and each commodity has its own demand curve. According to demand curves we can calculate consumer surplus (CS) of different portfolios of tourist destinations and later we sum up the total travel costs (including travel expenditure and TOC) and CS to come to the RVs of each portfolio. We then apply suitable proportions to calculate the RVs between different destinations in the portfolio. In the end, we add up all the RVs calculated for the objective destination. Using this method, we draw conclusions that Jiayuguan’s RV in 2006 includes national and international values, summing up to 738.4762 million yuan. The tourist expenditure, CS and TOC of Jiayuguan is proportionating 62.96, 32.28 and 4.76%, respectively. This study is also an example of non-market valuation of cultural tourism resources.  相似文献   
603.
Abstract

In despite of fluctuation in recent years, the grain yield in China has been increasing, which relieves the conflict between supply and demand and turns the situation of food security good. However, because of the rapid increase in food consumption, the conflicts of food quality and structure in the supply and demand equilibrium has become more and more obvious and the long-effective mechanism of food security has not been established yet. It is found that the factors affecting food security in China include the scarcity and dissipation of resources, farmers’ low enthusiasm in planting grain crops and the inappropriateness of the emphasis and measures of macro-economic regulation and control. Therefore, the authors advance to optimize resources allocation, strengthen macro-economic regulation and control and policy stimulation and establish the mechanism of allocating grain production cost, to set up the long-effective mechanism of China food security and keep it stable in the long term.  相似文献   
604.
Under the pressure of sustained growth in energy consumption in China, the implementation of a carbon pricing mechanism is an effective economic policy measure for promoting emission reduction, as well as a hotspot of research among scholars and policy makers. In this paper, the effects of carbon prices on Beijing’s economy are analyzed using input–output tables. The carbon price costs are levied in accordance with the products’ embodied carbon emission. By calculation, given the carbon price rate of 10 RMB/t-CO2, the total carbon costs of Beijing account for approximately 0.22–0.40% of its gross revenue the same year. Among all industries, construction bears the largest carbon cost. Among export sectors, the coal mining and washing industry has much higher export carbon price intensity than other industries. Apart from traditional energy-intensive industries, tertiary industry, which accounts for more than 70% of Beijing’s economy, also bears a major carbon cost because of its large economic size. However, from 2007 to 2010, adjustment of the investment structure has reduced the emission intensity in investment sectors, contributing to the reduction of overall emissions and carbon price intensity.  相似文献   
605.
The power sector in Thailand is the largest contributor to CO2 emissions. There is high potential to mitigate CO2 emission via alternative power generating plants. Alternative plants considered in this study include nuclear plants, integrated gasification combined cycle plants, biomass-based plants and supercritical thermal power plants. The biomass-based plants considered here are fueled with four types of biomass; paddy husk, municipal solid waste (MSW), fuel wood and corncob. The methodology for the optimal expansion plan of the power generating system over the planning horizon is based on the least-cost approach. The results from the least-cost planning analyses show that the nuclear alternative has the highest potential to mitigate not only CO2 but also other airborne emissions. Moreover, the nuclear option is the most effective abatement strategy for CO2 reduction due to its negative incremental cost of CO2 reduction.  相似文献   
606.
中国煤电行业的发展伴随着各种环境风险,本文以典型煤电企业为例,在产能过剩、能效标准提高、环境保护税、全国碳市场、水资源税和非水可再生能源规划目标的风险约束下,建立环境成本内部化和环境风险分析工具,考虑不同压力情境下对煤电企业价值的影响,构建环境风险影响财务成本的压力测试框架。结果表明,对单个风险而言,产能过剩和碳市场风险对企业价值的影响是大多数地区在不同情景中面临的主要风险驱动因素。对于综合风险压力测试而言,各地区1 000MW超超临界机组乐观情景及悲观情景的企业价值距合理回报预期企业价值相差小,而300MW和600MW亚临界机组因能效水平低、经营成本高等原因在环境风险压力下企业价值偏离合理回报较多。随着环境风险严重程度的不断增加,环境压力测试有助于煤电企业和金融机构了解环境风险对企业财务状况的影响,从而对投资决策产生影响。  相似文献   
607.
四川省珙县孝儿镇是国内在农村乡镇率先开展垃圾分类尝试的地区之一。论文采用成本分析法分析2011年四川孝儿镇垃圾管理年度成本的结构和特点,并根据成本分析结果计算垃圾管理的吨成本。分析显示在农村地区开展垃圾管理分类涉及到显性成本和隐性成本,在孝儿镇垃圾分类管理572058元的年度总开支中,显性成本占79%,隐性成本为21%。显性成本包括清运成本、终端处置和管理成本。隐性成本对长期开展垃圾分类有着重要的支持作用,包括监督和支持人力成本、社区能力建设和宣传教育成本。提高分类回收率和就近利用率以及吸引私人资本参与垃圾管理可优化成本,增强垃圾管理的经济可持续性。  相似文献   
608.
The purpose of this study is to estimate the environmentally attributable costs associated with diseases and disabilities in Oregon. We utilised actual Oregon data on disease rates and costs whenever available. If state-specific data were not available, we extrapolated from national estimates. We then used environmentally attributable fractions to estimate the environmentally attributable costs. The estimated environmentally attributable costs are the following: adult and childhood asthma: $29.6M; adult cardiovascular disease: $342.4M; adult and childhood cancer: $130.5M; childhood lead poisoning: $866.2M; birth defects: $3.0M; and childhood neurobehavioural disorders: $185M. Policymakers and researchers in other states are encouraged to apply the methods we have presented here to calculate the environmentally attributable costs associated with diseases and disabilities in their state. Knowing that many of the environmental contributors to disease are often preventable, policymakers are encouraged to make environmental public health a top priority.  相似文献   
609.
610.
The real burden of occupational diseases, specifically work-related musculoskeletal disorders (MSDs), and its impact on workers’ productivity is not known. The situation is critical in developing countries where only cases that cause workers’ disability are recorded. In this study, the incidence of MSDs in Colombia was estimated by using the age and gender specific double incidence rate of repetitive strain injuries diseases in Finland for 2002. The results showed that the estimated number of MSDs recorded in Colombia during 2005 was 23,477 cases at the rate of 11.6 cases per 10,000 workers. The estimated total cost of these MSD cases relative to workers’ productivity was US $171.7 million, representing around 0.2% of Colombia’s Gross Domestic Product for 2005. The systematic appraisal of the incidence of MSDs and their associated cost on workers’ productivity are necessary in developing countries to reduce the costly impact on productivity and to increase workers’ well-being.  相似文献   
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