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991.
C. Sch?fers T. Frische H.-C. Stolzenberg A. Weyers S. Zok und Th. Knacker 《Umweltwissenschaften und Schadstoff-Forschung》2008,20(3):229-233
Ohne Zusammenfassung
Hintergrundinformation Umweltbundesamt (2007). Abschlussbericht des Forschungsprojektes „Charakterisierung endokrin vermittelter Wirkungen in Fischen:
Relevante Parameter für die Entwicklung einer neuen OECD-Testmethode und in der Anwendung in der gesetzlichen Umweltrisikobewertung“
im Auftrag des Umweltbundesamtes (F?rderkennzeichen 206 67 470). Online erh?ltlich unter 相似文献
992.
Cultivated and settlement areas were studied in a small area (14 km2) in South Wollo, Ethiopia, by aerial photos, satellite images, field observations and interviews. Areas for cultivation/rural settlement decreased a few per cent between 1958 and 2013. Cultivated land per household slowly decreased in 1958–2003 but in 2003–2013 the annual decrease was 3–4 times higher. New farm buildings are often built on cultivated land, and abandoned buildings areas return to cultivation. Rainwater harvesting ponds have increased the areas with perennial crops that are important as a source of income. Tin roofed buildings are signs of improved livelihood. Very small farm size and rain-dependent agriculture combined with climate variability make food security vulnerable. Land-use inventories including remote sensing and local knowledge would be a valuable approach to assess livelihood needs. Further, it should involve decision makers at different levels, but local agricultural extension officers may play a central role. 相似文献
993.
994.
995.
Jes Vollertsen Asbj?rn Haaning Nielsen Henriette Stokbro Jensen Thorkild Hvitved-Jacobsen 《Water environment research》2008,80(2):118-126
A conceptual model that simulates the formation and fate of odorous substances in branched collection systems is presented. The model predicts the activity of the relevant biomass phenotypes under aerobic, anoxic, and anaerobic conditions in force mains and gravity sewers. The formation and fate of individual, malodorous substances in the bulk water, biofilms, and sediments are modeled. The release of odorous compounds from the bulk water to the sewer gas phase, their fate in the gas phase, and their subsequent release into the urban atmosphere is simulated. Examples of model application include the prediction of hydrogen sulfide and malodorous fermentation products from force mains and gravity sewers. 相似文献
996.
Maria da Gra?a Madeira Martinho Ana Isabel Silveira Elsa Maria Fernandes Duarte Branco 《Waste management & research》2008,26(5):484-490
This report proposes a new set of guidelines for the characterization of municipal solid waste. It is based on an analysis of reference methodologies, used internationally, and a case study of Valorsul (a company that handles recovery and treatment of solid waste in the North Lisbon Metropolitan Area). In particular, the suggested guidelines present a new definition of the waste to be analysed, change the sampling unit and establish statistical standards for the results obtained. In these new guidelines, the sampling level is the waste collection vehicle and contamination and moisture are taken into consideration. Finally, focus is on the quality of the resulting data, which is essential for comparability of data between countries. These new guidelines may also be applicable outside Portugal because the methodology includes, besides municipal mixed waste, separately collected fractions of municipal waste. They are a response to the need for information concerning Portugal (e.g. Eurostat or OECD inquiries) and follow European Union municipal solid waste management policies (e.g. packaging waste recovery and recycling targets and the reduction of biodegradable waste going to landfill). 相似文献
997.
Zusammenfassung
Hintergrund und Ziel Die Exposition gentechnisch ver?nderter Kulturpflanzen erfordert die Beobachtung ihrer Umweltwirkungen. Ziel der Beitragsserie
über die Beobachtung ?kologischer Wirkungen von GVO ist es, den hierzu erreichten Stand der Wissenschaft vorzustellen. Da
bei einem Bundesl?nder und ggf. europ?ische Staaten übergreifenden Monitoring besonders auf methodisch vergleichbare und r?umlich
aussagekr?ftige Daten zu achten ist, werden in diesem einführenden Beitrag wissenschaftstheoretische und statistische Grundlagen
des Monitoring sowie die Standardisierung der Beobachtungsverfahren behandelt.
Schwerpunkte Im Mittelpunkt stehen zun?chst ?kologische Anforderungen an das GVO-Monitoring. Um mit GVO ggf. zusammenh?ngende Umweltver?nderungen
ermitteln zu k?nnen, ist eine Eingliederung in bestehende Umweltbeobachtungsprogramme erforderlich. GVO-Exposition und-Wirkung
sind aufeinander bezogen über die Organisationsstufen ?kologischer Systeme hinweg zu erfassen. Ein effizientes und suffizientes
Monitoring bedarf eines wissenschaftstheoretisch und statistisch soliden Designs. Deshalb werden einem weiteren Schwerpunkt
dieses Beitrags wissenschaftstheoretische Grundlagen der Hypothesenbildung und-prüfung behandelt. Hierfür bedarf es Daten,
die mehreren, im Einzelnen behandelten Qualit?tskriterien entsprechen müssen. Eines dieser Kriterien ist die r?umliche und
zeitliche Verallgemeinerungsf?higkeit der Monitoring-Befunde, die in dem dritten Schwerpunkt des Beitrags dargestellt wird.
Schlussfolgerungen Für die Prüfung von Hypothesen über Umweltfolgen von GVO sind konsequent ?kosystemforschung und Monitoring eng miteinander
zu vernetzen. Denn sie erfüllen komplement?re Funktionen, die für das Monitoring der Umweltwirkungen von GVO von gro?er praktischer
und wissenschaftlicher Bedeutung sind.
Empfehlungen Das GVO-Monitoring sollte in bestehende Programme der ?kosystemforschung und der Umweltbeobachtung eingebettet werden und
die ?kologischen Organisationsstufen sowie GVO-Exposition und-Wirkung einschlie?en. Die Lokalisierung der Messorte sollte
die erwartete Exposition oder Wirkung berücksichtigen.
Perspektiven Weitere Beitr?ge dieser Serie werden die Messplanung, das Pollenmonitoring und die r?umliche Verallgemeinerung von Ergebnissen
standortspezifischer Messungen oder Modellierungen behandeln.
Environmental monitoring of ecological impacts of GMOs
Goal, Scope and Background The release of genetically modified organisms (GMOs) may result in ecological impacts to be monitored. This series presents the state-of-art concerning the environmental monitoring of ecological impacts of GMOs. Since this monitoring is conducted by several authorities, the methodical comparability and spatial validity of the monitoring data is crucial. Thus, the respective fundamentals of philosophy of science and of statistics as well as the methodical standardisation form the focus of this article. Main Features At first, the monitoring requirements will be described from the viewpoint of ecology. Consequently, the GMO monitoring needs to be integrated into existing programmes. Exposure and effects of GMOs have to be monitored across the hierarchy of ecological organisation. For monitoring to be efficient and sufficient, the design must be founded in terms of philosophy of science and statistics. Hence the fundamentals concerning the verification of hypotheses represent another feature of this article. The data used for the verification of hypotheses must comply with quality criteria. One of these criteria is the spatial and temporal extrapolation of the monitoring results, which is the third feature in this introductory article. Conclusions The evaluation of hypotheses on GMO impacts requires the linkage to ecosystems research and environmental monitoring. These both are, in terms of methodology, complementary and of significant technical and scientific value for GMO monitoring. Recommendations GMO-monitoring should closely be connected with ecosystems research and environmental monitoring. The levels of ecological organisation should be covered as well as the exposure and the effects of GMOs. The expected GMO exposure and effects should be considered by localising the monitoring sites. Perspectives Further articles of this series will deal with network designing, GMO pollen monitoring and extrapolation of site-specific measurements and modelling results.相似文献
998.
Hydroxylated polybrominated diphenyl ethers (OH-PBDEs) and methoxylated polybrominated diphenyl ethers (MeO-PBDEs) are present in the ecosystem of the Baltic Sea. OH-PBDEs are known to be both natural products from marine environments and metabolites of the anthropogenic polybrominated diphenyl ethers (PBDEs), whereas, MeO-PBDEs appear to be solely natural in origin. Polybrominated dibenzo-p-dioxins (PBDDs) are by-products formed in connection with the combustion of brominated flame retardants (BFRs), but are also indicated as natural products in a red alga (Ceramium tenuicorne) and blue mussels living in the Baltic Sea. The aims of the present investigation were to quantify the OH-PBDEs and MeO-PBDEs present in C. tenuicorne; to verify the identities of PBDDs detected previously in this species of red alga and to investigate whether cyanobacteria living in this same region of the Baltic Sea contain OH-PBDEs, MeO-PBDEs and/or PBDDs. The red alga was confirmed to contain tribromodibenzo-p-dioxins (triBDDs), by accurate mass determination and additional PBDD congeners were also detected in this sample. This is the first time that PBDDs have been identified in a red alga. The SigmaOH-PBDEs and SigmaMeO-PBDEs concentrations, present in C. tenuicorne were 150 and 4.6 ng g(-1) dry weight, respectively. In the cyanobacteria 6 OH-PBDEs, 6 MeO-PBDEs and 4 PBDDs were detected by mass spectrometry (electron capture negative ionization (ECNI)). The PBDDs and OH-PBDEs and MeO-PBDEs detected in the red alga and cyanobacteria are most likely of natural origin. 相似文献
999.
1000.
The Clean Development Mechanism (CDM) was introduced by the Kyoto Protocol to provide a financial incentive to establish project activities in developing countries for reducing greenhouse gas emissions while also fostering sustainable development. This article shows that waste management project activities play an important role in achieving the aims of the CDM. It describes how these activities have to prove additionality, how the emission reductions must be calculated and monitored in order to be eligible and in order to lead to Certified Emission Reductions (CERs). The article further provides an analysis about the various challenges that are involved in applying the CDM scheme to waste management project activities, which require a new specific set of technical skills and regulatory standards. 相似文献