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401.
402.
David M Lodge Susan Williams Hugh J MacIsaac Keith R Hayes Brian Leung Sarah Reichard Richard N Mack Peter B Moyle Maggie Smith David A Andow James T Carlton Anthony McMichael 《Ecological applications》2006,16(6):2035-2054
The Ecological Society of America has evaluated current U.S. national policies and practices on biological invasions in light of current scientific knowledge. Invasions by harmful nonnative species are increasing in number and area affected; the damages to ecosystems, economic activity, and human welfare are accumulating. Without improved strategies based on recent scientific advances and increased investments to counter invasions, harm from invasive species is likely to accelerate. Federal leadership, with the cooperation of state and local governments, is required to increase the effectiveness of prevention of invasions, detect and respond quickly to new potentially harmful invasions, control and slow the spread of existing invasions, and provide a national center to ensure that these efforts are coordinated and cost effective. Specifically, the Ecological Society of America recommends that the federal government take the following six actions: (1) Use new information and practices to better manage commercial and other pathways to reduce the transport and release of potentially harmful species; (2) Adopt more quantitative procedures for risk analysis and apply them to every species proposed for importation into the country; (3) Use new cost-effective diagnostic technologies to increase active surveillance and sharing of information about invasive species so that responses to new invasions can be more rapid and effective; (4) Create new legal authority and provide emergency funding to support rapid responses to emerging invasions; (5) Provide funding and incentives for cost-effective programs to slow the spread of existing invasive species in order to protect still uninvaded ecosystems, social and industrial infrastructure, and human welfare; and (6) Establish a National Center for Invasive Species Management (under the existing National Invasive Species Council) to coordinate and lead improvements in federal, state, and international policies on invasive species. Recent scientific and technical advances provide a sound basis for more cost-effective national responses to invasive species. Greater investments in improved technology and management practices would be more than repaid by reduced damages from current and future invasive species. The Ecological Society of America is committed to assist all levels of government and provide scientific advice to improve all aspects of invasive-species management. 相似文献
403.
Irena Rot-Nikcevic Christopher N. Taylor Richard J. Wassersug 《Behavioral ecology and sociobiology》2006,60(1):116-25
Tadpoles can alter their behavior, morphology, and life history in response to habitat change. Although chemical signals from
conspecifics or predators play an important role in tadpole habitat assessment, little is known about the role of visual cues
and the extent to which tadpoles rely on their vision for intraspecific social assessment. The aim of our experiments was
to determine whether larval anurans use visual images of other tadpoles as indicators of density and to analyze how, and to
what extent, images of conspecifics alone affect tadpole development, growth, and behavior. To assess this, we raised both
Rana sylvatica and Bufo americanus tadpoles in aquaria with either quarter- or half-mirrored walls. Both physically increased density and increased density
simulated with mirrors decreased tadpole growth and developmental rates, and increased activity in Rana tadpoles. Bufo tadpoles did not significantly alter their growth and development in response to visually increased density. Only true, i.e.,
physically, increased density had an effect on growth and activity in Bufo tadpoles. Our data show that images of conspecifics are used as visual cues by Rana tadpoles and can induce phenotypically plastic changes in several traits. This response to visual cues is taxon-specific.
An erratum to this article can be found at 相似文献
404.
Joyeeta Gupta Richard Howarth Peter Sand Oran Young 《Environmental geochemistry and health》2004,26(4):435
Announcement
International Environmental Agreements:Politics, Law and Economics (INEA) 相似文献405.
406.
Richard Ogutu-Ohwayo 《Conservation biology》1993,7(3):701-711
As in Lake Victoria and Lake Kyoga, most of the native fish species of Lake Nabugabo have either been depleted or have disappeared since Lates niloticus , Nile perch, and Oreochromis niloticus , a tilapiine, were introduced. L. niloticus, O. niloticus, Schilbe intermedius, Brycinus jacksonii , and Rastrineobola argentea are the only species still abundant and widespread in the lake. Of the five haplochromine species endemic to Lake Nabugabo, at least one has vanished and the remaining ones are very rare. The prey of the Nile perch in Lake Nabugabo, with the exception of the prawn Caridina nilotica , which is absent from the lake, are similar to those the predator switched to in Lakes Victoria and Kyoga after haplochromines had been depleted. These consist of ephemeropterans—especially Povilla , the anisopteran nymphs R. argentea , tilapiines, and juvenile Nile perch. Three small lakes adjacent to Lake Nabugabo—Lake Kayanja, Lake Kayugi, and Lake Manywa—contain large numbers of Oreochromis esculentus and two haplochromine species previously known only in Lake Nabugabo. These three lakes should be designated conservation areas for the cichlids and other native species that were previously abundant in Lakes Victoria, Kyoga, and Nabugabo. The swamps around these lakes should be protected so that the Nile perch does not spread into them. Further research should be carried out to ensure the preservation of the endemic species. 相似文献
407.
Richard H. Yahner 《Conservation biology》1996,10(2):672-673
408.
The duration of cirral withdrawal in Balanus glandula (Darwin) varies by a factor of three depending on the type of stimulus applied. Contact with potential predators including thaidid gastropods (Thais emarginata, T. lamellosa), and forcipulate asteroids (Leptasterias hexactis, Pycnopodia helianthoides) elicits significantly longer withdrawal durations than contact with an herbivorous gastropod (Tegula pulligo), a grazing, spinulosid asteroid (Henricia leviuscula) or a neutral, brown algal stimulus (Fucus distichus). By substantially attenuating the release of metabolites, prolonged withdrawal probably increases the likelihood of being bypassed by nonvisual predators relying on chemical cues to verify that barnacles are alive. The reduced response to the non-predatory species indicates that this is not a generalized response to gastropods or asteroids, but rather that it appears to be specific to potential predatory species. 相似文献
409.
Biodiversity across a Rural Land-Use Gradient 总被引:6,自引:0,他引:6
Jeremy D. Maestas § Richard L. Knight † Wendell C. Gilgert‡ 《Conservation biology》2003,17(5):1425-1434
410.