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491.
以武汉中心城区的东沙湖流域为研究对象,以7项下垫面及3项降雨因子为影响因子,以18项河湖水环境因子为响应变量,基于冗余分析研究多尺度下两者之间的关系.结果表明:在所研究的10项影响因子中,硬质铺装面积率和河网水面率是东沙湖流域城市河湖水环境的主要影响因子,贡献率达0.703和0.652,城市道路面积率则是3000m及以外缓冲区尺度下的主要影响因子,贡献率达0.796,降雨的空间分布不是主要影响因子,贡献率低于0.371;影响因子对水环境影响的尺度效应与排水管网的有无和水文汇水单元尺度的大小密切相关;东沙湖流域的河湖水污染可归因于以硬质铺装为代表的不透水面上的面源污染和经由排水管网运移排放的点源污染,河网水面率则是改善水环境的关键因素.  相似文献   
492.
Morgan R 《Disasters》1985,9(1):44-50
This article describes the indicators and data sources used by the Botswana Drought Early Warning System formally established in early 1984, the main uses of the indicators in the assessment of drought conditions and the design of relief programmes are outlined. Limitations of the sources of data available are discussed, as is the feasibility of adding some possible further indicators. In conclusion, the importance of a functioning Early Warning System in a country highly susceptible to repeated droughts is stressed, in the context of die current effort to elaborate a comprehensive National Food Strategy and to establish a Regional Early Warning System for Southern Africa.  相似文献   
493.
Decision-makers require useful tools, such as indicators, to help them make environmentally sound decisions leading to effective management of hazardous wastes. Four hazardous waste indicators are being tested for such a purpose by several countries within the Sustainable Development Indicator Programme of the United Nations Commission for Sustainable Development. However, these indicators only address the 'down-stream' end-of-pipe industrial situation. More creative thinking is clearly needed to develop a wider range of indicators that not only reflects all aspects of industrial production that generates hazardous waste but considers socio-economic implications of the waste as well. Sets of useful and innovative indicators are proposed that could be applied to the emerging paradigm shift away from conventional end-of-pipe management actions and towards preventive strategies that are being increasingly adopted by industry often in association with local and national governments. A methodological and conceptual framework for the development of a core-set of hazardous waste indicators has been developed. Some of the indicator sets outlined quantify preventive waste management strategies (including indicators for cleaner production, hazardous waste reduction/minimization and life cycle analysis), whilst other sets address proactive strategies (including changes in production and consumption patterns, eco-efficiency, eco-intensity and resource productivity). Indicators for quantifying transport of hazardous wastes are also described. It was concluded that a number of the indicators proposed could now be usefully implemented as management tools using existing industrial and economic data. As cleaner production technologies and waste minimization approaches are more widely deployed, and industry integrates environmental concerns at all levels of decision-making, it is expected that the necessary data for construction of the remaining indicators will soon become available.  相似文献   
494.
对15家氨氮自动监测设备比对试验考核不合格的污水厂及印染厂的考核情况进行了分析,发现目前水污染源氨氮自动监测设备比对试验考核指标存在一些问题。结合水污染源在线监测系统运行与考核技术规范以及地表水自动监测技术规范,提出了水污染源氨氮自动监测系统按照不同排放浓度实施不同比对试验考核指标的建议。  相似文献   
495.
Changes in marine ecosystems can be manifested in many different ways, on different temporal and spatial scales. Seabirds are top consumers in marine foodwebs and offer opportunities to detect and assess the biological effects of changes in physical parameters (sea-surface temperature [SST], salinity, depth of thermocline etc.) of the marine ecosystem. We compare six-eight years' of data on the biology (diet, and breeding success) of four species of seabird (arctic tern Sterna paradisaeaand common tern S. hirundo, which feed at the sea surface; and Atlantic puffin Fratercula arctica and razorbill Alca torda, which dive 30–60 m for their prey) breeding on Machias Seal Island (MSI) in the Bay of Fundy with both our own meteorological and oceanographic measurements, and with standard measurements from conventional sources. These are compared with fisheries data on changes in the main prey of all the seabirds concerned (juvenile or 0-group herring Clupea harengus) which are the most direct link between the seabirds and the physical properties of the marine system. We explore relationships between seabird productivity and diet, and other aspects of both herring biology (larval surveys, and fat content) and oceanography (SST data from the island, and remotely sensed data from the entrance to the Bay of Fundy). Timing of laying by puffins followed SST variation at neither the local (MSI) nor regional scales, but at the scale of the North Atlantic, following the trend of populations breeding off northern Norway. The proportion of herring in the diet of terns over 6 years varied inversely with herring larval abundance the previous fall; this relationship was not statistically significant in the puffin and razorbill. A major new finding is the considerable (50%) inter-annual variation in the energy density (fat content) of juvenile herring that are the main seabird prey; breeding success of both species of tern varied in parallel with the energy density of juvenile herring in the diet until the last two years of the study, when sandlance (Ammodytes sp.) and euphausid shrimp predominated in the diet. Our long-term research approach combines traditional population monitoring (of numbers of breeding birds) with demographic, behavioural and environmental monitoring, to provide new understanding of the marine ecosystem as well as of seabirds.  相似文献   
496.
The Great Lakes Water Quality Agreement stipulates that the Governments of Canada and the United States are responsible for restoring and maintaining the chemical, physical and biological integrity of the waters of the Great Lakes Basin Ecosystem. Due to varying mandates and areas of expertise, monitoring to assess progress towards this objective is conducted by a multitude of Canadian and U.S. federal and provincial/state agencies, in cooperation with academia and regional authorities. This paper highlights selected long-term monitoring programs and discusses a number of documented ecological changes that indicate the present state of the open and nearshore waters of the Great Lakes.  相似文献   
497.
This paper considers the use of meiofauna (benthic metazoa 45 to 500 m in size) as biological indicators for monitoring marine environmental health. To date, this abundant and ubiquitous group of invertebrates has been largely neglected in applied sampling programmes; instead, emphasis has been placed upon more conspicuous biological components such as seagrass, macrofauna and epiphytes. In an attempt to redress this balance, this paper sets out three objectives: (1) to explain the reasons for selecting biological response indicators from across the whole spectrum of phylogenetic organisation, (2) to summarise those aspects of meiofaunal life-history and demography that render this group suitable for monitoring anthropogenic pollution and disturbance, (3) to suggest how to optimise the inclusion of meiofauna in monitoring programmes so that they provide maximum information for management purposes. To achieve these objectives the environmental impact assessment framework of Ward and Jacoby (1992) is adopted as a matrix into which the relevant components of meiofaunal ecology are fitted. Using this matrix, meiofauna are shown to have advantages that include their sessile habit, high species diversity, short generation time, direct benthic development and ubiquitous distribution. Disadvantages include their small size, high level of spatial and temporal variability, the potential cost of sample processing and the limited taxonomic literature accessible to non-specialist workers. The paper concludes with a discussion of sampling strategies and methods of analysis that may be used to efficiently incorporate meiofauna as biological response indices into environmental monitoring. Emphasis is placed on cost-effective techniques such as taxonomic minimalism.  相似文献   
498.
With its total drainage basin of 37 107 km2 and mean annual discharge of 307 m3 s-1, the River Kymi is one of the largest in Finland. Presently it receives treated domestic wastewaters of about 160 000 inhabitants through eight treatment plants and treated industrial effluents from four paper mills, two cardboard mills and one pulp mill. In the 1960s all the wastewaters were discharged untreated to the river. However, the construction of domestic wastewater treatment plants began in the 1970s and mechanical wastewater treatment became common in industry. By the end of the 1980s practically all the wastewaters discharged to the river were treated in activated sludge processes. The aim of this paper was to investigate the influence of wastewater purification on the bacteriological quality of the river during these three decades. The bacteriological quality of the river was evaluated on the basis of annual medians of fecal streptococci (FS) calculated for 15 sites on the basis of 4804 FS enumerations from the years 1964-1992. The results show that the bacteriological quality improved steadily as the number of treatment plants increased and wastewater treatment became more effective. In the beginning of the 1960s the annual FS medians in the central part of the river were typically 1000-1500 CFU/100 ml, whereas in the 1990s they had decreased to 30-40 CFU/100 ml (CFU = colony forming units). The results indicate that FS input to the river was mainly of domestic origin.  相似文献   
499.
Organic farming is expected to contribute to conserving national biodiversity on farms, especially remnant, old, and undisturbed small biotopes, forests, and permanent grassland. This objective cannot rely on the legislation of organic farming solely, and to succeed, farmers need to understand the goals behind it. A set of indicators with the purpose of facilitating dialogues between expert and farmer on wildlife quality has been developed and tested on eight organic farms. “Weed cover in cereal fields,” was used as an indicator of floral and faunal biodiversity in the cultivated land, and “uncultivated biotope area” on the farm was used as a general measure of wildlife habitats. Functional grouping of herbaceous plants (discriminating between “high conservation value” plant species and “competitive”/“ruderal” species) and low mobility butterflies were used as indicators of conservation value, especially focusing on the few sites left with considerable remnant conservation value. The dialog processes revealed that the organic farmers’ ideas and goals of conservation of wildlife quality were not necessarily the same as for biologists; the farmers expressed very different opinions on the biological rooted idea, that wildlife quality is related to the absence of agricultural impact. However, farmers also stated that the information given by the indicators and especially the dialogue with the biologist had influenced their perception and awareness of wildlife. We conclude that, combined with a dialogue process, using these indicators when mapping wildlife quality could be an important key component of a farm wildlife management advisory tool at farm level.  相似文献   
500.
A Disturbance Index for Karst Environments   总被引:13,自引:0,他引:13  
Karst environments, unique from other environments, require their own disturbance index. Karst resources are increasingly disturbed by a variety of processes related to social, physical, and economic factors. Recent studies have begun to qualify and quantify these disturbances, yet their focus has been limited to one or two factors such as biotic, geomorphic, or economic impacts. A more holistic approach, addressing economic, scientific, and cultural factors, is needed, to effectively assess the threats to karst areas. Currently, there is no efficient method to measure, compare, and contrast the disturbance of karst environments. We propose a hierarchal and standardized environmental disturbance index as a tool to measure regional impacts and highlight the areas of the karst system that require more protection or study. Addressed categories of disturbance include cultural, biotic, atmospheric, hydrological, and geomorphologic impacts.  相似文献   
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