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881.
Global Earth Observation (GEO) is one of the most important sources of information for environmental resource management and disaster prevention. With budgets for GEO increasingly under pressure, it is becoming important to be able to quantify the returns to informational investments. For this, a clear analytical framework is lacking. By combining Bayesian decision theory with an empirical, stakeholder-oriented approach, this paper attempts to develop such a framework. The analysis focuses on the use of satellite observations for Dutch water quality management in the North Sea. Dutch water quality management currently relies on information from 'in situ' measurements but is considering extending and deepening its information base with satellite observations. To estimate returns to additional investments in satellite observation, we analyze the added value of an extended monitoring system for the management of eutrophication, potentially harmful algal blooms and suspended sediment and turbidity in the North Sea. First, we develop a model to make the potential contribution of information to welfare explicit. Second, we use this model to develop a questionnaire and interpret the results. The results indicate that the expected welfare impact of investing in satellite observation is positive, but that outcomes strongly depend on the accuracy of the information system and the range of informational benefits perceived. 相似文献
882.
Towards Participatory Geographic Information Systems for community-based environmental decision making 总被引:3,自引:0,他引:3
Jankowski P 《Journal of environmental management》2009,90(6):1966-1971
This article discusses the potential of Geographic Information Systems (GIS) to become an information technology enabling groups of people to participate in decisions shaping their communities and promoting sustainable use of natural resources. It explains the concept of participation in the context of planning and decision making. In this context Participatory GIS (PGIS) offers tools that can be used to help the public become meaningfully involved in decision making processes affecting their communities. Following an overview of research on PGIS and its current status the article presents two recent studies of PGIS in water resource planning; one involving the use of computer generated maps representing simple information structures and the other involving the use of more sophisticated information tools. The synthesis of both studies provides the bases for discussing the prospects of PGIS to empower citizens in making decisions about their communities and resources. 相似文献
883.
Rinaldo Brau Antonello E. Scorcu Laura Vici 《Journal of Environmental Planning and Management》2009,52(1):25-42
This paper assesses the appeal of potential interventions on the tourism offer of Rimini, a popular Italian seaside holiday destination, by means of a choice modelling analysis. Tourism can be viewed as a composite good, its overall utility depending on the arrangement of the component characteristics. The discrete choice experiments here incorporate as attributes a number of possible changes to current tourist activities (the subject of public debate), including them in hypothetical alternative holiday packages. The conditional logit analysis indicates that tourists show lesser preference for interventions aimed at protecting the environmental integrity of the beach and greater preference for those, such as the creation of a pedestrianised seafront with late-night opening of amenities and facilities, that are likely to diminish the role of the traditional sea, sun and sand component of the overall holiday experience. 相似文献
884.
Kirstin Dow Richard L. Murphy Gregory J. Carbone 《Journal of the American Water Resources Association》2009,45(1):187-197
Abstract: The increasing availability of web mapping tools creates new opportunities to bridge decision‐makers’ climate information needs with technical capabilities. These new tools, however, raise familiar, unresolved issues related to cartographic representation. Using an on‐line drought mapping tool, this study seeks to understand which spatial unit best meets the desire drought managers have for “local” information, their comprehension of uncertainties introduced in mapping information at local scales, and their willingness to trade off accuracy for information at a desired unit. We found that the most useful local map information includes regional context and boundaries which present their local area of interest. Even among this experienced, well‐educated, professional group, those who had not taken a GIS or cartography class did not fully recognize the role of interpolation in creating and introducing uncertainty to some drought maps. Those who did recognize the uncertainty introduced by interpolation still strongly favored maps that provided estimated values for all areas vs. station point accuracy. Mapping poses a unique set of challenges to communicating risk and uncertainty. As more decision‐support efforts incorporate web mapping, greater attention is needed to assure that users understand the tradeoffs between accuracy and precision in creating local information, the imprecision of boundaries, as well as the limits of forecasts. Clearly conveying spatial accuracy and uncertainty is a challenge that merits greater attention in using maps to communicate drought and other environmental risk information. 相似文献
885.
我国造纸工业对环境的污染及解决方法 总被引:6,自引:0,他引:6
本文论述造纸工业的主要污染源及解决造纸工业对环境污染问题的关键技术和方法, 提出我国造纸工业环境保护的基本对策,认为我国的造纸工业也能成为洁净工业。 相似文献
886.
本文对区域水环境规划决策支持系统的总体结构进行介绍,论述了系统数据库,知识库,模型库的设计思路,结果表明系统可作为水环境规划的有效辅助工具,同时对该系统进一步开发完善了进行了探讨。 相似文献
887.
888.
889.
基于决策树的统计预报模型在臭氧浓度时空分布预测中的应用研究 总被引:2,自引:0,他引:2
近地面层臭氧是光化学污染的主要污染物之一.臭氧污染不仅严重影响着空气质量并且危害人类健康与动、植物生长.本研究以徐州市为研究区,基于环境监测站连续监测数据分别采用分类回归树(CART)、随机森林(RF)和M5模型树方法建立臭氧浓度统计预报模型,选取1、4、7、10等4个月作为季度代表进行区域臭氧浓度预测的研究.以2015整年逐小时徐州市国控大气监测站实时监测的臭氧浓度(因变量)和气象因子数据(自变量)为训练样本建立臭氧浓度统计预报模型.模型验证结果表明,总体上3种决策树模型能够较好的预测臭氧浓度动态变化特征,月尺度上预测值与观测值相关系数均值为0.68,平均绝对误差和均方根误差均值分别为21.63μg·m~(-3)和27.42μg·m~(-3).在此基础上,基于站点观测所建立臭氧统计预报模型,以WRF模型模拟的气象场作为输入,预报区域网格化臭氧预报值,并发现臭氧浓度空间分布与站点观测特征总体一致性较好.经与观测值进行对比,结果表明两者相关系数均值为0.58,平均绝对误差及均方根误差分别为29.38μg·m~(-3)和37.15μg·m~(-3),预报准确率均高于75%.同时利用周步长观测值与预测值建立的多元线性集合预报回归方程对3种决策树模型的预报值进行修正,在一定程度上提高了预报值的精度. 相似文献
890.
In this article, coke plant wastewater was treated by a simultaneous nitrifying and denitrifying (SND) fixed biofilm hybrid system. The results showed that suitable parameters of the system were important for the performance of the bio-degradation system. The chemical oxygen demand (COD) removal efficiency in this system was satisfactory, higher than 94%, and ammonia nitrogen was higher than 95%. The effluent COD concentration could meet the discharge standard, except for very few situations. The results showed that a sufficient carbon source was important for making ammonia nitrogen concentration meet the discharge standard. Then the TiN removal efficiency in this system can be brought higher than 94%. Dissolved oxygen (DO) is very important to the performance of the SND bio-degradation system, and the suitable DO is about 3.5-4.0 mg/L at the forepart of reactor. In addition, the performance of the system was almost not affected by pH value. The results show that the system is feasible to treat coke plant wastewater. 相似文献