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Summary After discussing methods for and the difficulties of determining optimal land use, particularly in relation to conservation and sustainability issues, prospects for establishing conservation networks so as to preserve the wildemess characteristics of the Cape York Peninsula area are considered. According to a number of international studies, nature conservation in this region should be given a high priority. While Cape York is sparsely settled, it is not, however, a complete wilderness. Mining, cattle ranching, forestry, fishing, tourism and land use by Aborigines, frequently conflict with nature conservation in this region. But most of the land currently belongs to the Crown (State), even though Crown title is now subject to counter-claims by Aborigines following the Mabo case which is outlined, and most is held as leasehold by its users. In theory, leasehold from the Crown should give considerable scope for altering land use in the region, and instituting a system of conservation networks in the area based on core protected areas, such as those suggested by the Wildlife Preservation Society of Queensland. Nevertheless, strategic land use planning for Cape York Peninsula is difficult because knowledge about the stock of natural resources and current land uses in the region is very imperfect, and conflicts between interest groups at the regional, State and national level are unlikely to allow for easy harmonious resolutions of land use disputes.But an encouraging sign in favour of nature conservation as a land use in Cape York Peninsula is its low economic opportunity cost, except where it comes into conflict with mining. Net returns from extensive pastoralism appear to be negative and economic returns from forestry are low. Tourism could be compatible with conservation. Potential conflicts with mining could be taken into account in the early planning stages of conservation networks by gazetting very large nature reserves and at a later time allowing some portions to be assigned for mining. The royalties from such mining might be used as transfer payments to benefit further conservation efforts in the region.Dr Andreas E. Hohl is a staff member and Professor Clem A. Tisdell is a Department Head of the Department of Economics at the University of Queensland. 相似文献
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We have determined feasibility and levels of agreement for visualizing the nuchal translucency within a time limit with three-dimensional (3D) and two-dimensional (2D) transvaginal ultrasound. A total of 213 women of median gestational age 13 weeks (range 11–14 weeks) undergoing first-trimester nuchal translucency (NT) thickness measurements with 2D transabdominal ultrasound were included in the study. Additionally all women underwent 2D and 3D transvaginal NT examination within a time limit of 90 s. These two methods were compared with each other and with our standard method (2D transabdominal ultrasound) with respect to visualization of fetal nuchal fold and to the levels of agreement. The nuchal fold was visualized by 3D and 2D transvaginal ultrasound in 85.9% (95% CI: 80.5%, 90.3%) and 25.8% (95% CI: 20.1%, 32.2%), respectively (p<0.001). There was a statistically significant underestimation of the NT by 2D transabdominal as compared with 3D transvaginal ultrasound of 0.1 mm (p<0.001), and by 3D transvaginal as compared with 2D transvaginal ultrasound of even 0.1 mm (p<0.001). 3D transvaginal ultrasound of the nuchal fold has increased feasibility to 2D transvaginal ultrasound within a short examination time and with minimal, but significant, measurement differences. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
217.
Sílvia Bofill-Mas Byron Calgua Pilar Clemente-Casares Giuseppina La Rosa Marcello Iaconelli Michele Muscillo Saskia Rutjes Ana Maria de Roda Husman Andreas Grunert Ingeburg Gräber Marco Verani Annalaura Carducci Miquel Calvo Peter Wyn-Jones Rosina Girones 《Food and environmental virology》2010,2(2):101-109
The presence of human adenoviruses (HAdV) in recreational water might cause disease in the population upon exposure. HAdV detected by PCR could also serve as indicators of the virological water quality. In order to assess the applicability of HAdV to the evaluation of the faecal contamination in European bathing waters, a real-time quantitative PCR assay was used for the quantification of HAdV in 132 samples collected from 24 different recreational marine and freshwater sites in nine European countries. Selected samples presenting positive nested PCR results for HAdV were analyzed using quantitative PCR and 80 samples from a total of 132 produced quantitative results with mean values of 3.2 × 102 per 100 ml of water, being human adenovirus 41 the most prevalent serotype between the samples where adenovirus was typified. HAdV were quantified in samples from all 15 surveillance laboratories. Statistical analysis showed no homogeneous linear relation between HAdV and E. coli, intestinal enterococci or somatic coliphages concentrations in the tested samples when considering all the data together. Significant correlations between HAdV and at least one of the other indicators were observed only when data from individual laboratories were considered. The quantification of HAdV may provide complementary information in relation to the use of bacterial standards in the control of water quality in bathing water. 相似文献
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The new WIOD database allows for improved empirical analysis on a wide range of important environmental research questions.In this paper we demonstrate the scientific power of the WIOD database and analyze very urgent policy questions on the impacts of international trade and structural change on the environment.We apply recent econometric approaches to show the impact of international trade on the environment via its different channels as for instance to increase welfare and potentially affect environmental regulation as well as countries’sector.This approach has become known as the econometric structural decomposition method.In addition to these guidelines by the literature,an econometric panel data approach is offered to shed some light on the impact of structural change and international trade on environmental pressure,where we especially address and solve several endogeneity issues that add further complexity to the analysis. 相似文献
219.
Who is importing forest products from Africa to China? An analysis of implications for initiatives to enhance legality and sustainability 总被引:1,自引:0,他引:1
Wenbin Huang Andreas Wilkes Xiufang Sun Anne Terheggen 《Environment, Development and Sustainability》2013,15(2):339-354
Global forest product value chains are increasingly subject to regulatory requirements, such as legality and sustainability certification. For African forest products, a shift in the export destinations of forest products towards China, the leading timber product manufacturer, has raised concerns that social and environmental product and process standards are declining. Aggregate drivers of this shift have been documented, yet there has been little enterprise-level analysis of Chinese actors in African timber imports based in China. This paper provides an initial analysis, highlighting implications for existing and emerging regulatory initiatives. Data show that although an increasing number of Chinese private enterprises is engaged in African timber imports, import volumes remain concentrated among a small number of geographically clustered private and state-owned firms. Government-led schemes are beginning to address timber legality concerns. But given China’s growing domestic market for finished wood products, sustainability certification requirements driven by the US and EU will not be sufficient to ensure improved sourcing by Chinese firms. 相似文献
220.
Andreas Schierling Karlheinz Seifert Sebastian R. Sinterhauf Julian B. Rieß Johanna C. Rupprecht Konrad Dettner 《Chemoecology》2013,23(1):45-57
The pygidial gland secretion of the rove beetle genera Stenus Latreille and Dianous Leach is composed of pyridine and piperidine-derived alkaloids and several terpene compounds. Two-choice bioassays with ants and fish, as well as agar diffusion assays, revealed that the secretion compounds are capable of deterring predators and protecting the beetles from infestation with microorganisms. In addition, the beetles use the secretion for rapid movements on the water surface, a process called skimming. Thus, originally developed to chemically defend the sensitive unprotected abdomen from predator attacks, the secretion of recent Steninae can be designated as multifunctional. Four of the alkaloid compounds occur as different configurational isomers in the secretion. Two-choice tests showed that ants discriminate between stereoisomers of stenusine, while there was no effect visible on bacteria in agar diffusion assays. Furthermore, there are evolutionary trends within the Steninae concerning the secretion composition, as some of the alkaloids primarily occur in phylogenetically basal species, while others are mainly restricted to derived species. 相似文献