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791.
Thomas?WinklerEmail author Wilfried?Winiwarter 《Mitigation and Adaptation Strategies for Global Change》2016,21(8):1181-1196
In the present paper, national and externally organized projections of greenhouse gas emissions for Austria were compared to gain insight on the underlying scenario data assumptions. National greenhouse gas emission trends extend until 2030, an assessment of European Union (EU) countries to 2050. In addition, data for 2000–2100 was extracted from the global emission database described by the Representative Concentration Pathways (RCP). By identifying trends in these projections, it was possible to produce (a) a long-term assessment of national scenarios until 2100, (b) an assessment of the ambition level toward national climate strategies, and (c) a standardized method to compare trends across countries. By extracting RCP data, Austrian’s methane, nitrous oxide, and carbon dioxide emissions up to 2100 could be projected for all sources as well as specific sectors. With respect to the RCP scenario emission data, national projections did not seem to employ the mitigation potentials available for the most stringent RCP scenario, RCP2.6. Comparing projections that supported the EU Climate Strategy 2030 with national projections revealed similar trends. Because RCP2.6 is the only scenario consistent with a 2 °C global warming target, and it is much more ambitious than any of the national or European projections, further measures will be required if Austria is to adequately contribute to this widely accepted policy goal. 相似文献
792.
SUMMARY In many developing countries, the determination of a ranking of investments designed to improve and extend the road system is a commonplace prerequisite of planning for the transport sector as a whole and the road sub-sector within it. A major objective of determining investment priorities is to secure the greatest efficiency in the use of resources allocated to the sector and, for this reason, any system of assigning priorities must rely upon conventional investment appraisal techniques producing quantifiable measures of worth. Exercises of this kind, in which road investments are identified and ranked, are usually undertaken to produce a road sector investment plan. The implementation of such plans is, however, often compromised because of perceived deficiencies with a methodology which places undue reliance on investment appraisal and fails to properly address the issue of public interest and sustainability. This paper attempts to produce a pragmatic set of ground rules which, while mindful of the need to promote economic efficiency, allow for other factors to be embraced in a more holistic methodology. 相似文献
793.
794.
Frédéric Coulon William Cowie Simon Pollard Graeme Risdon Kirk T. Semple Graeme I. Paton 《Environmental pollution (Barking, Essex : 1987)》2010,158(10):3032-3040
A six month field scale study was carried out to compare windrow turning and biopile techniques for the remediation of soil contaminated with bunker C fuel oil. End-point clean-up targets were defined by human risk assessment and ecotoxicological hazard assessment approaches. Replicate windrows and biopiles were amended with either nutrients and inocula, nutrients alone or no amendment. In addition to fractionated hydrocarbon analysis, culturable microbial characterisation and soil ecotoxicological assays were performed. This particular soil, heavy in texture and historically contaminated with bunker fuel was more effectively remediated by windrowing, but coarser textures may be more amendable to biopiling. This trial reveals the benefit of developing risk and hazard based approaches in defining end-point bioremediation of heavy hydrocarbons when engineered biopile or windrow are proposed as treatment option. 相似文献
795.
796.
Queen conch, Strombus gigas, is a commercially important gastropod that has been exploited throughout the Caribbean islands for thousands of years. Shell
middens in the region are the physical record of a long-term fishery and their study can provide valuable information on selectivity
patterns followed by fishermen and on resulting morphological shifts reflected by shells. In this study, we surveyed 27 middens
located at Los Roques, Venezuela, to assess pre-Columbian and modern fisheries and measure their impact on local populations
of queen conch. Pre-Columbian middens, covering a period of approximately 350 years of exploitation (1160–1540 A.D.), were
mostly composed of adult shells (89%) and mean length of catch was estimated at 22.4 ± 0.2 cm (mean ± SE). A decrease in mean
length of catch was observed throughout the modern fishery regime, estimated at 22.2 ± 0.3 cm in 1950–1971 and 20.0 ± 0.3 cm
in 1990–1995. Higher proportions of immature individuals ranging from 48 to 67% were found in modern middens. Additionally,
a decrease in mean length of mature individuals was detected throughout the modern fishery regime. The appearance of younger
and smaller specimens is considered as a sign of heavy exploitation of local populations of queen conch during modern fisheries.
Pre-Columbian middens in contrast, permitted to establish a relative baseline from which to compare values registered throughout
modern times. 相似文献
797.
798.
Konstanze Sch?nthaler 《Umweltwissenschaften und Schadstoff-Forschung》2001,13(2):107-116
Am Beispiel des l?nderübergreifenden Biosph?renreservates Rh?n wurde das Konzept einer ?kosystemaren Umweltbeobachtung konkretisiert. Die Arbeiten dienten der Operationalisierung der hohen fachlichen Anforderungen des Rats von Sachverst?ndigen für Umweltfragen an eine ‘Allgemeine ?kologische Umweltbeobachtung’, die medienund sektorübergreifende sowie m?glichst weitgehend harmonisierte Datenerhebungen und eine integrierte Datenauswertung vorsieht. Es werden die Bausteine einer stufenweisen Harmonisierung der Datenerhebung und Auswertung vorgestellt. Vertiefend behandelt werden Fragen nach methodischen Ans?tzen für eine nachvollziehbare Auswahl von Beobachtungsr?umen und Messtandorten sowie für die r?umliche Verallgemeinerung von Beobachtungsergebnissen. Das Konzept der ?kosystemaren Umweltbeobachtung nutzt hierfür das Instrument der bundesweiten standort?kologischen Raumgliederung sowie geostatistische Verfahren zur r?umlichen Zusammenführung bestehender Beobachtungsprogramme und Messnetze. Ferner werden M?glichkeiten aufgezeigt, wie mit der Durchführung hydrologischer Gebietsanalysen und mit einem ?kosystemarem Wasserhaushaltsmodell auf der Grundlage verfügbarer Daten integrierende Aussagen zur Entwicklung von Wassereinzugsgebieten getroffen werden k?nnen. 相似文献
799.
800.