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521.
Anne Gro Vea Salvanes Victoria A. Braithwaite 《Behavioral ecology and sociobiology》2005,59(2):250-257
Many re-introduction programs used for conservation of populations and species threatened with extinction advocate the use of enriched rearing environments to train animals how to behave appropriately in the wild. Curiously, most of the current fish re-stocking programs have paid little attention to lessons previously learned in bird and mammal re-introductions. Many rehabilitation programs that use releases of hatchery fish observe higher mortality in released fish compared to wild, with most mortality arising shortly after release. One explanation for this mortality is based purely on selection processes; many hatchery fish normally selected out of the population thrive in the predator free, food-rich hatcheries. Alternatively, mortalities may be high because hatchery nursery environments fail to shape fish behaviour appropriately. Here, we empirically address the effect of enrichment in the early rearing environment in coastal cod (Gadus morhua). We find asymmetries in aggressive behaviour when fish reared in plain or enriched environments are allowed to interact. Furthermore, cod reared in standard, impoverished, hatchery environments spend less time in shelter, are more active, and show weaker anti-predator responses than fish reared with access to heterogeneous spatial cues. These results suggest that the constant, plain environments of fish farms may generate behavioural deficits that could reasonably be expected to be associated with lower survival in fish released into the wild. 相似文献
522.
Hale SS Miglarese AH Bradley MP Belton TJ Cooper LD Frame MT Friel CA Harwell LM King RE Michener WK Nicolson DT Peterjohn BG 《Environmental monitoring and assessment》2003,81(1-3):133-148
Understanding the ecology, condition, and changes of coastal areas requires data from many sources. Broad-scale and long-term ecological questions, such as global climate change, biodiversity, and cumulative impacts of human activities, must be addressed with databases that integrate data from several different research and monitoring programs. Various barriers, including widely differing data formats, codes, directories, systems, and metadata used by individual programs, make such integration troublesome. Coastal data partnerships, by helping overcome technical, social, and organizational barriers, can lead to a better understanding of environmental issues, and may enable better management decisions. Characteristics of successful data partnerships include a common need for shared data, strong collaborative leadership, committed partners willing to invest in the partnership, and clear agreements on data standards and data policy. Emerging data and metadata standards that become widely accepted are crucial. New information technology is making it easier to exchange and integrate data. Data partnerships allow us to create broader databases than would be possible for any one organization to create by itself. 相似文献
523.
Anne Ingeborg Myhr Terje Traavik 《Journal of Agricultural and Environmental Ethics》2003,16(4):317-335
The main purpose of The NorwegianGene Technology Act (1993) is to enforcecontainment of genetically modified organisms(GMOs) and control of GMO releases.Furthermore, the Act intends to ensure that``production and use of GMOs should take placein an ethically and socially justifiable way,in accordance with the principle of sustainabledevelopment and without detrimental effects tohealth and the environment.' Hence it isobvious that, for the Norwegian authorities,sustainable development is a normativeguideline when evaluating acceptableconsequences of GMO use and production. Inaccordance with this, we have investigated theextent to which the sustainability criteriawere decisive for the destiny of one approvedand one declined application of geneticallymodified plant release. The presentunderstanding of the ecological,socio-economical, and cultural consequences ofGMO use and release is fragmentary anduncertain. We consider the PrecautionaryPrinciple and the notion of equitabledistribution as key issues within thesustainable development framework, henceconstituting important foundations for ouranalyses. The Act is legitimizingsustainability criteria, but does not seem tosecure their conversion into concrete action.We envisage a more conscious implementation ofthe Norwegian Gene Technology Act.Sustainability concerns ecological, economical,and social values, and these can only beensured through long-term thinking, initiationof independent risk-associated research, andbroad involvement of all stakeholders in theevaluation of GMO issues and concerns. 相似文献
524.
In this study, a substance chain approach as a tool contributing to a sustainable development has been tested by applying it to zinc. An analysis of the western world zinc substance chain has been made in order to identify the main routes of zinc losses from the chain. Technologically feasible options to improve the management of the chain have been selected and applied to a modelled chain. With the emphasis on resource management, the model has been designed to evaluate the impact of options on the input of primary zinc into the chain. The consequences of the options for the energy resources have been analyzed.Redesigning the global zinc chain using the chosen technologically feasible options has lead to a lower primary zinc input when compared to the present chain, but a 45% primary zinc input is still needed, while the improved chain requires 8% less energy. To obtain a further decrease of primary zinc input in the chain, research should focus on emission abatement during zinc usage, where especially corrosion of galvanized steel forms a problem, and on the prevention of mixed-product waste streams with a low average zinc concentration. The energy analysis shows that options to improve the zinc chain should be carried out carefully, avoiding extra demands on the energy resources.The study indicates that designing a substance chain, along with even simple modelling, results in a good tool to calculate the impact of different kinds of options on the total chain. 相似文献
525.
Integrating science into resource management activities is a goal of the CALFED Bay-Delta Program, a multi-agency effort to address water supply reliability, ecological condition, drinking water quality, and levees in the Sacramento–San Joaquin Delta of northern California. Under CALFED, many different strategies were used to integrate science, including interaction between the research and management communities, public dialogues about scientific work, and peer review. This paper explores ways science was (and was not) integrated into CALFED's management actions and decision systems through three narratives describing different patterns of scientific integration and application in CALFED. Though a collaborative process and certain organizational conditions may be necessary for developing new understandings of the system of interest, we find that those factors are not sufficient for translating that knowledge into management actions and decision systems. We suggest that the application of knowledge may be facilitated or hindered by (1) differences in the objectives, approaches, and cultures of scientists operating in the research community and those operating in the management community and (2) other factors external to the collaborative process and organization. 相似文献
526.
John McKenna J. Andrew G. Cooper Anne Marie O’Hagan 《Journal of Coastal Conservation》2009,13(2-3):165-173
The European Recommendation on Integrated Coastal Zone Management has six core principles. These form two groups, one concerned with strategic goals and one that has a local focus. The principles are presented as a menu of free-standing options, with no prioritization either within or between groups. In the case of coastal erosion management these characteristics result in irreconcilable conflicts, and actively hinder sustainable management of eroding coasts. The principles require clarification, and recognition that they are an indivisible integrated set which should not be used to select principles to advance a particular agenda. It is essential that the strategic principles are given priority, because only they can underpin a sustainable approach to the issue of coastal erosion. 相似文献
527.
Anne A. Shirinian-Orlando Christopher G. Uchrin 《Journal of the American Water Resources Association》2000,36(4):749-757
ABSTRACT: This paper presents a method for determining the causes of salinization of surface waters, in this case the upper Colorado River and its tributaries in Texas. The analysis, which includes a combination of statistical analysis and graphical methods, indicates that among the sources of salt (e.g., saline ground water discharge into surface waters and storm runoff, both surface and shallow subsurface, and washing minerals into surface waters) the major contributor is saline ground water, which discharges into the river and streams. Data also points to salt plume intrusion into the river and streams from sources of salt in the aquifers. 相似文献
528.
Maud Leriche Didier Voisin Nadine Chaumerliac Anne Monod Bernard Aumont 《Atmospheric environment (Oxford, England : 1994)》2000,34(29-30)
A multiphase box model for a remote environment of the troposphere has been developed with an explicit chemistry for both gas and aqueous phase. The model applied to a set of measurements performed by Voisin et al. (2000) during the European CIME experiment for a cloud event on 13th December 1997 at the top of the Puy de Dôme (France). The results of the simulation are compared to the measurements in order to follow the evolution of the ambient chemical composition as a function of the pH and of the varying water content. After verifying that the model retrieves the main features observed in the behavior of species in the cloud droplets, a detailed analysis of the simulated chemical regime is performed. It essentially discusses the sources and sinks of radical in aqueous phase, the relative importance of the oxidation pathways of volatile organic compounds by the main radicals and the conversion of S(IV) into S(VI) which seems to be influenced by the presence of peroxonitric acid, HNO4, in aqueous phase in the environmental conditions that are considered with low H2O2. These numerical results are then compared with the theoretical study from Herrmann et al. (2000), who proposed a slightly different mechanism, including C2 chemistry and transition metal chemistry whereas they neglect some reaction pathways, such as the one involving OHCH2O2 radical. This double confrontation between model results and both real experimental data and numerical results from Herrmann et al. (1999c) underlines limitations of such modeling approach that does not include any dynamical or microphysical coupling but also demonstrates its capability to identify the main oxidants or reactants in aqueous phase in real environmental conditions more realistic than a purely theoretical approach. The originality of this study resides in the explicit and exhaustive ways the chemical reactions are treated in aqueous phase and in a first attempt to compare such a detailed chemical scheme to real environmental conditions. 相似文献
529.
Support for the use of treated gray water as an alternative water resource in the Middle East and North Africa is high, especially given the lack of religious restrictions against its use, but several obstacles have kept application of treated gray water near 1 % in some areas. The largest of obstacles include the cost of treatment and the ambiguity surrounding the health safety of gray water and treated gray water. This paper aims to provide an overview of current gray water practices globally, with specific focus on household-level gray water practices in the Middle East and North Africa region, and highlight the need for cost reduction strategies and epidemiological evidence on the use of household-level gray water and treated gray water. Such actions are likely to increase the application of treated gray water in water-deprived areas of the Middle East and North Africa. 相似文献
530.
Winter-flooding of ricefields provides foraging habitat to waterfowl, which in return may bring agronomic benefits to farmers. Our study experimentally tested the effect of mallards (Anas platyrhynchos) on the standing stalks and weed seed bank in the Camargue (France), both of which present major challenges for farmers. Three duck densities were tested: (D1) 5 ducks ha−1 (historical nocturnal density), (D2) 23 ducks ha−1 (present nocturnal density), and (D3) 300 ducks ha−1 (Asian rice-duck farming density). The ducks reduced the stalks significantly: −27 % (D1), −52 % (D2), and −91 % (D3). Conversely, they decreased the number of seeds by only 3 % (D3) and the seed mass by about 21 % (D1 and D3), which was not significant. Besides they had no effect on seed species richness. This study clearly demonstrates that the winter-flooding effect on straw decomposition can be enhanced by waterfowl foraging, hence showing an agronomic benefit from ducks to farmers. However, there was no clear effect in terms of seed bank reduction. 相似文献