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71.
Monitoring of the ocean environment in southern California, USA, has been conducted by a diverse array of public and private organizations with different motivations, working on a variety of spatial and temporal scales. To create a basis from which to integrate information from these diverse programs, we conducted an inventory of ocean monitoring activities in the Southern California Bight to address the following questions: (1) How much money is being expended annually on marine monitoring programs? (2) Which organizations are conducting the most monitoring? (3) How are resources allocated among the different types of monitoring programs? This inventory focused on programs existing, or those expected to be in existence, for at least 10 years and that were active at any time between 1994 and 1997. For each program identified for inclusion in this study, information was collected on the number of sites, sampling intensity, parameters measured, and methods used. Levels of effort were translated into cost estimates based upon a market survey of local consulting firms. One hundred fourteen marine monitoring programs, conducted by 65 organizations and costing US $31 million annually, were identified. Most of the effort (81 programs, 65% of samples, 70% of costs) was expended by ocean dischargers as part of their compliance with National Pollutant Discharge Elimination System (NPDES) permit requirements. Federal programs (11 programs, 25% of samples, 10% of total expenditures) expended more than state or local government programs. More than one quarter of monitoring expenditures were conducted to measure concentrations and mass of effluent inputs to the ocean. The largest effort expended on receiving water monitoring was for measuring bacteria, followed by sediments, fish/shellfish, water quality, and intertidal habitats. The large level of expenditures by individual agencies has presented opportunities for integrating small, site-specific ocean monitoring programs into regional- and national-scale monitoring and assessment programs. 相似文献
72.
73.
模糊信息优化处理方法在陕西泾阳南塬塬边斜坡稳定性区划中的应用 总被引:1,自引:0,他引:1
结合野外调查,应用模糊信息优化处理方法对泾阳南塬塬边斜坡各评价单元进行了评价,最后根据评价结果将塬边斜坡进行了稳定性区划. 相似文献
74.
以马尾松为指示植物,对韶关的土壤进行了长期淋溶模拟并记录其化学状态。结果发现,土壤溶液的pH值下降到4.0,Bs值下降到几乎为零,有较大量的A1离子溶出。最后选取土壤溶液pn〉4.0、KS〉10%和[Al^3+]〈0.1mmol/L为临界化学指标,参考国内外应用广泛的MAGIC模型和SMART模型,确定韶关酸沉降临界负荷(S的临界负荷)为14.1keq/hm^2.a。 相似文献
75.
Analysis of Damaging Hydrogeological Events: The Case of the Calabria Region (Southern Italy) 总被引:3,自引:0,他引:3
A period of bad weather conditions due to prolonged intense rainfall and strong winds can trigger landslides, floods, secondary
floods (accumulation of rain on surfaces with low permeability), and sea storms, causing damage to humans and infrastructure.
As a whole, these periods of bad weather and triggered phenomena can be defined as damaging hydrogeological events (DHEs).
We define a methodological approach based on seven simple indexes to analyze such events. The indexes describe the return
period (T) and trend of rainfall, the extent of hit areas, and the level of damages; they can be considered attributes of
georeferenced features and analyzed with GIS techniques. We tested our method in an Italian region frequently hit by DHEs.
In a period of 10 years, 747 damaging phenomena (landslides, 43%; floods, 38%) and 94 DHEs have been classified. The road
network and housing areas are the most frequently damaged elements, threatened by all types of damaging phenomena. T classes
are almost in accordance with the level of damage. These results can be used to outline warning levels for civil protection
purposes, to forecast the areas most likely to be hit and the potential ensuing damage, to disseminate information concerning
vulnerable areas, and to increase people’s awareness of risk. 相似文献
76.
Climate Change and Climate Variability: Adaptations to Reduce Adverse Health Impacts 总被引:2,自引:0,他引:2
Global climate change is likely to have a range of consequences for human health as a result of disturbance or weakening of the biosphere's natural or human-managed life support systems. The full range of potential human health impacts of global climate change is diverse and would be distributed differentially spatially and over time. Changes in the mortality toll of heatwaves and changes in the distribution of vector-borne infectious diseases may occur early. The public health consequences of sea level rise and of regional changes in agricultural productivity may not occur (or become apparent) for several decades. Vulnerability is a measure of both sensitivity to climate change and the ability to adapt in anticipation of, or in response to, its impacts. The basic modes of adaptation to climate-induced health hazards are biological, behavioural and social. Adaptation can be undertaken at the individual, community and whole-population levels. Adaptive strategies should not introduce new health hazards. Enhancement of the acknowledged public health infrastructure and intervention programmes is essential to reduce vulnerability to the health impacts of climate change. In the longer-term, fundamental improvements in the social and material conditions of life and in the reduction of inequalities within and between populations are required for sustained reduction in vulnerability to environmental health hazards. 相似文献
77.
Andrew Warren 《环境科学学报(英文版)》2007,19(4):470-474
This article explores the assessment of sustainability in fields subject to wind erosion. In the first part, simple sustainability audits are examined, as of soil depth and nutrients. Direct measurement of these characteristics has many problems, largely because of huge variability in space and time at all scales. Modelling still has its problems, but it may be possible to overcome many of them soon. It is true that wind erosion preferentially removes soil nutrients, but there are imponderables even here. The nutrient balance in many of these soils includes considerable input from dust. In West Africa, it has been shown that the amounts of calcium and potassium that are added in dust are sufficient to fertilize dispersed crops. In mildly acidic sandy soils, such as those found on the widespread palaeo- aeolian deposits, much of the phosphorus is fixed and unavailable to plants by the time it is removed by wind erosion, so that erosion has no added downside. Most of the nutrients carried by dust have been shown to travel close to the ground (even when they are attached to dust-sized particles), and so are trapped in nearby fallow strips, and are thus not lost to the farming system. Second, the sustalnabillty of a whole semi-arid farming system is explored. Wind erosion in semi-arid areas (like China, the Sahel and Norflawestern Europe) generally takes place on aeolian deposits of the recent geological past. Most of these soils are deep enough to withstand centuries of wind erosion before they are totally lost to production, and some of these soils have greater fertility at greater depth (so that wind erosion may even improve the soil). Finally some remarks are made about environmental change in relation to sustainability. 相似文献
78.
Quevauviller P 《Environmental science and pollution research international》2007,14(5):297-307
Science-policy integration is one of the many complex challenges that scientific and policy-making communities are facing.
It involves knowledge sharing and exchanges among a wide range of disciplines and actors. In many instances, the lack of proper
communication and of a coordination mechanism leads to research outputs not being used or simply known by policy-makers, and
to policy research needs not being communicated to the scientific communities in a timely fashion. This paper discusses the
integration of scientific and technological progress into the policy-making and implementation process, with emphasis on water
policies. It highlights the need and complexity of developing a knowledge-based approach which would enable to lead to an
operational science-policy interface linked to WISE (Water Information System for Europe), including the newly developed WISERTD
webportal ().
The views expressed in this paper are purely those of the author and do not in any circumstances reflect an official position
of the European Commission. 相似文献
79.
Jason Matus 《Disasters》2007,31(S1):S91-S103
Currently, the pace of recovery in the 'Three Areas' is moving faster than the implementation of the Comprehensive Peace Agreement (CPA). This gap is leading to greater imbalances in income, unsustainable urbanization, overexploitation of the environment and resource based conflict. Unless regulated, the likely result will be chronic poverty and an undermining of the success of the CPA. Agencies must be mindful of how they provide assistance so that they support the CPA. The analysis of food security should take place in the context of a larger political, social and economic analysis of the emerging situation. The least developed areas should be prioritised and interventions should provide benefits to the full range of socioeconomic groups. WFP must identify its role in the wider and integrated response. It should support the emerging peace process and the key reforms. If WFP chooses to consolidate its activities, it will require capable strategic partners. If it chooses to invest more in building the capacity of government and community structures, it must improve its skill base and field presence 相似文献
80.
David M. Coley Peter R. Waylen 《Journal of the American Water Resources Association》2006,42(4):851-862
ABSTRACT: The Peace River at Arcadia, Florida, is a municipal water supply supplement for southwestern Florida. Consequently, probabilities of encountering low flows during the dry season are of critical importance. Since the association between Pacific Ocean sea surface temperatures (SSTs) and seasonal streamflow variability in the southeastern United States is well documented, it is reasonable to generate forecasts based on this information. Here, employing historic records of minimum, mean, and maximum flows during winter (JFM) and spring (AMJ), upper and lower terciles define “above normal,”“normal,” and “below normal” levels of each variable. A probability distribution model describes the likelihood of these seasonal variables conditioned upon Pacific SSTs from the previous summer (JAS). Model calibration is based upon 40 (of 50) years of record employing stratified random sampling to ensure equal representation from each decade. The model is validated against the remaining 10 samples and the process repeated 100 times. Each conditional probability distribution yields varying probabilities of observing flow variables within defined categories. Generally, a warm (cold) Pacific is associated with higher (lower) flows. To test model skill, the forecast is constrained to be the most probable category in each calibration year, with significance tested by chi‐square frequency tables. For all variables, the tables indicate high levels of association between forecast and observed terciles and forecast skill, particularly during winter. During spring the pattern is less clear, possibly due to the variable starting date of the summer rainy season. This simple technique suggests that Pacific SSTs provide a good forecast of low flows. 相似文献