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901.
Robin M. Reich Raymond L. Czaplewski William A. Bechtold 《Environmental and Ecological Statistics》1994,1(3):201-217
In this study a cross-correlation statistic is used to analyse the spatial relationship among stand characteristics of natural, undisturbed shortleaf pine stands sampled during 1961–72 and 1972–82 in northern Georgia. Stand characteristics included stand age, site index, tree density, hardwood competition, and mortality. In each time period, the spatial cross-correlation statistic was used to construct cross-correlograms and cumulative cross-correlograms for all significant pairwise combination of stand characteristics. Both the cross-correlograms and cumulative cross-correlograms identified small-scale clustering and weak directional gradients for different stand characteristics in each time period. The cumulative cross-correlograms, which are based on inverse distance weighting were more sensitive in detecting small-scale clustering than the cross-correlograms based on a 0–1 weighting. Further analysis suggested that the significant cross-correlation observed among basal area growth and other stand characteristics were due, in a large part, on a subset of sample plots located in the northern part of the state, rather than regional or broad-scale variation as first thought. The ability to analyse the spatial relationship between two or more response surfaces should provide valuable insight in the development of ecosystem level models and assist decision makers in formulating pertinent policy on intelligent multiresource management. 相似文献
902.
The paper maintains that, as a means toward achieving the ideal of a sustainable development, industrial waste should best be regarded in business-economic terms as having the same basic status as regular products. It is shown how an approach to proportioning industrial costs to waste that is described can be applied to the Polluter-Pays Principle in a way incorporating this principle into a company's internal estimation system. In two case studies presented, use of this approach is found to generate a waste-reducing incentive through showing waste to have a negative impact on estimates of profit. 相似文献
903.
Traditional environmental knowledge (usually imparted orally) is being lost from many regions of the world, requiring novel forms of transmission if this situation is to be redressed. Loss of this knowledge may be a significant contributory factor towards ecological decline. Undoubtedly, disruption to ecosystems and societies that depend on these has impacted on traditional land management practices, with negative ramifications for biodiversity. From an environmental perspective, scientists in northern Australia need to understand traditional Aboriginal methods of ‘caring for country’, such as burning regimes, so that these can be incorporated into strategies today for maintaining Australia’s rich biodiversity. However, information exchange should be two-way: as well as learning from local people, science can in turn benefit people who may have little experience of, for example, invasive species. The challenge is how can the complexity of biological knowledge from within different ontologies be represented and integrated in a way that it can be of use to scientists and local people, in order to ensure a sustainable future? The main aim of this study was to record existing local knowledge of biodiversity for the community of Aurukun (far north Queensland), integrating this knowledge with scientific data, while giving parity to both knowledge systems and protecting intellectual property rights. A cross-cultural collaboration between community members and ethnobiologists resulted in development of the Aurukun Ethnobiology Database. An interdisciplinary approach was taken to effectively model autochthonous biological knowledge and scientific data to create a database with a number of practical applications. 相似文献
904.
Puerto Rican Parrots and Potential Limitations of the Metapopulation Approach to Species Conservation 总被引:1,自引:0,他引:1
905.
Dr. William C. Metz 《Environmental geochemistry and health》1982,4(4):131-140
After a lapse of almost two decades, US energy and mining companies are once again involving themselves with worker housing. Reinvolvement began in the 1970s. It is in response to a recognition of the fiscal consequences of project delays and an industry responsibility to both workers and project area communities. It differs from the heavy reliance on company towns which were prevalent in the US during the 19th and early 20th Centuries. Industry involvement now relies not only on supply, but on stimulation. A greater variety of housing initiatives is being utilised and a company must carefully select the housing initiative best suited to its circumstances. These initiatives need to be guided by the following set of decision guidelines: (1) housing function; (2) housing user; (3) housing type and quantity needs; (4) monetary expectations; (5) role of the industry; (6) housing unit location; (7) responsibilities after housing is completed; and (8) amenities and community sharing. Then, housing involvement must be reviewed in light of past and present industry experiences. Innovative ideas need to be evaluated with respect to proven initiatives, as well as their presumed goal and potential for success.Study performed under Contract No. DE-AC02-76CH00016 with the U.S. Department of Energy 相似文献
906.
Models of parasite-mediated sexual selection have thus far overlooked the potential effects of parasites of females on their
hosts’ ability to choose mates. A set of models addressing this issue is developed, each building on the previous one to add
complexity and realism to the framework. The selection coefficient for parasite immunity and brightness is estimated using
the ratio of the fitness of susceptible males to the fitness of immune males. Parasite-induced reduction in female choosiness
can substantially relax the selection for bright, immune males, especially when: (1) immunity to parasites is rare in the
population, (2) parasites are not highly aggregated within the host population, (3) parasites are abundant, and (4) the effects
of parasites on male brightness or female choosiness are severe. Parasite-induced variability in male brightness is most likely
to occur in populations in which parasites are abundant and not aggregated; if females in those populations show a reduced
preference for bright males, sexual selection for brightness (and parasite immunity) will still operate but exert a weaker
selective pressure.
Received: 4 November 1994/Accepted after revision: 9 September 1995 相似文献
907.
Summary Female mating frequency was studied in the laboratory in field crickets, Gryllus integer. Females mated 9.8 times on average (N = 46, SD = 6.6, range = 1–30) in 10-day observations of 5 h each. Offspring from each female were raised and the mating frequency determined for 10 female offspring from from each family. Female offspring mated from 0 to 26 times. The average number of matings across all families was 7.3 (SD = 3.4, range 1.9–16.2). Regression of daughter mating frequency on mother mating frequency resulted in a statistically significant slope of 0.345 and a narrow sense heritability estimate of 0.69 (SE = 0.29). Additive genetic variation is available for selection on female mating frequency in G. integer. Results are discussed in terms of selection on female mating frequency.
Offprint requests to: W.H. Cade 相似文献
908.
Since the early 1990s the U.S. government has been developing and implementing public policies that advance the redevelopment of brownfields, and the recent passage of the Small Business Liability Relief and Brownfields Revitalization Act (SBLRBRA) will significantly advance efforts to integrate environmental contamination mitigation and redevelopment. Experience has demonstrated that successful redevelopment requires the collection, analysis, and interpretation of environmental data in a timely and cost‐effective manner in order to allow developers and lenders to efficiently use cleanup resources, develop response strategies that integrate cleanup with redevelopment, and support meaningful outreach to involved stakeholders. Recent advances in the science and technology of site characterization hold the promise of improved site characterization outcomes while saving time and money. One such advancement, the Triad Approach, combines systematic up‐front planning with the use of a dynamic field investigation process and the generation of real time data to allow in‐field decision making on sample location selection. This article describes an application of the Triad Approach to redevelopment of an urban greenway in Trenton, New Jersey. The Triad Approach, initiated through a partnership between the City of Trenton, New Jersey Department of Environmental Protection, New Jersey Institute of Technology, and the U.S. Environmental Protection Agency, demonstrated that this approach could accelerate the characterization of the 60‐acre, 11‐parcel project area. Environmental issues that were solved using the Triad Approach included the delineation of the extent of historic fill, determination of no further action for several areas of concern, detailed investigation of specific impacted areas and the acquisition of sufficient data to allow the city to make important decisions regarding remediation costs and property acquisition. © 2003 Wiley Periodicals, Inc. 相似文献
909.
Rodney L. Clouser William L. Miller 《Journal of the American Water Resources Association》1980,16(3):453-458
ABSTRACT: A study was undertaken to determine the effect of water intensive appliances or activities on household water consumption. Activities included in the study were use of the washing machine, dishwasher, swimming pool, and lawn watering. In the majority of cases these activities increased per capita consumption and were statistically significant. Households included in the study were not familiar with water saving devices available in the retail market. Even if tehse appliances were purchased, private economic benefits to the household would be low due to the inexpensive water charges levied. However, aggregate community benefits could be large if new well drilling cost or increase in storage facilities could be avoided. In order to avoid these increased costs, regulation or subsidy programs may be the most efficient policy alternatives available to the communities. Subsidies and regulation could potentially decrease water use and offer alternatives to increasing the water supply. 相似文献
910.