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591.
Resource-rich states throughout the developing world are prone to rent-seeking, excessive borrowing, wasteful spending, and unbalanced growth as well as states with weak institutions and authoritarian regimes. Are the five energy-rich Soviet successor states necessarily doomed to repeat this experience, often referred to as the “resource curse”? This paper advances and tests the hypothesis that Russia and Kazakhstan are more likely to avoid the “resource curse” than Uzbekistan, Turkmenistan, and Azerbaijan because they privatized their energy sectors. Specifically, we find that privatization offers a potential path out of the “resource curse” when it involves a transfer of ownership to domestic actors. Although Kazakhstan initially appeared to be developing a viable tax regime in response to foreign investors, over the long term Kazakhstan’s tax regime has become increasingly volatile and dependent upon these foreign investors. In contrast, domestic oil companies are helping to foster the development of an increasingly viable tax regime in Russia. 相似文献
592.
593.
Spatial pattern and persistence of historical fire boundaries in southern interior British Columbia 总被引:2,自引:0,他引:2
Geraldine J. Jordan Marie-Josée Fortin Kenneth P. Lertzman 《Environmental and Ecological Statistics》2008,15(4):523-535
Recent ecosystem and fire management research aims to quantify, model and understand historical fire disturbances focusing
on their frequency, size and distribution. Less attention, however, has been paid to fire boundaries and their location on
the landscape. Our study presents a spatial method to quantify the location, pattern and persistence of historical fire boundaries
using tree ring fire scar data in the lower Stein watershed (British Columbia). Data from Pinus ponderosa and Pseudotsuga menziesii collected in 35 one-hectare plots over a 412-hectare study area were analyzed for the period between 1879 and 1947 using
local spatial statistics and boundary detection techniques. Results of the analysis using local spatial statistic Moran’s
I showed significant clustering of boundaries near topographic breaks. To determine and test whether fire boundaries between
plots were persistent, we used boundary detection methods and developed a spatially restricted randomization test. The results
revealed that out of 86 possible boundary links, 8 were significantly persistent (P < 0.025) while another 8 were significantly rare (P < 0.025). These spatial methods can help determine the historical spatial configuration of persistent boundaries and can
be used to maintain natural forest dynamics.
相似文献
Geraldine J. JordanEmail: |
594.
分析了金华江流域地表水污染的原因,提出了以开展“碧水行动”为中心的包括产业调整和限制、环境容量总量控制、环境基础设施建设、强化环境管理等在内的综合治理措施。 相似文献
595.
This paper examines the effect that endangered species regulation has on natural resource development. Specifically, we use data from competitive auctions to estimate the effect that land-use regulation protecting endangered caribou in the Canadian province of Alberta has on the price producers pay for the right to extract oil. We exploit a regression discontinuity design to evaluate how prices differ along regulation boundaries that constrain resource development. The auction format and the regulation discontinuity allow us to measure the total cost of the regulation. We find that producers pay 24% less on average for oil leases that are regulated and that the total net present value cost of the regulation exceeds $1.15 billion for leases sold between 2003 and 2012, all of which is borne by the government. In spite of these costs, the populations of endangered caribou remain in widespread decline. 相似文献
596.
概述了我国工业企业搬迁污染场地在法律法规、标准体系、及目前政府相关部门对工业企业搬迁污染场地实施监督管理的现状,指出了目前我国在法律法规、土壤环境标准体系及污染场地管理体系中存在的主要问题,以及通过健全法律法规、完善标准体系、明晰管理体系以及提高环境管理者业务水平等措施,解决工业企业搬迁污染场地管理中的问题,保障工业企业搬迁污染场地的环境安全。 相似文献
597.
Aude Zingraff-Hamed Frank Hüesker Christian Albert Mario Brillinger Joshua Huang Gerd Lupp Sebastian Scheuer Mareen Schltel Barbara Schrter 《Ambio》2021,50(8):1610
Nature-based solutions (NBS) for mitigating climate change are gaining popularity. The number of NBS is increasing, but research gaps still exist at the governance level. The objectives of this paper are (i) to give an overview of the implemented NBS for flood risk management and mitigation in Germany, (ii) to identify governance models that are applied, and (iii) to explore the differences between these models. The results of a hierarchical clustering procedure and a qualitative analysis show that while no one-size-fits-all governance model exists, polycentricism is an important commonality between the projects. The study concludes by highlighting the need for further research on traditional governance model reconversion and paradigm changes. We expect the findings to identify what has worked in the past, as well as what is important for the implementation of NBS for flood risk management in future projects.Electronic supplementary materialThe online version of this article (10.1007/s13280-020-01412-x) contains supplementary material, which is available to authorized users. 相似文献
598.
The natural range of variation of ecosystems provides reference conditions for sustainable management and biodiversity conservation. We review how the understanding of natural reference conditions of boreal forests in northern Europe has changed from earlier perceptions of even-aged dynamics driven by stand-replacing disturbances towards current understanding highlighting the role of non-stand-replacing disturbances and the resultant complex forest dynamics and structures. We show how earlier views and conceptual models of forest disturbance dynamics, including the influential ASIO model, provide estimates of reference conditions that are outside the natural range of variation. Based on a research synthesis, we present a revised forest reference model incorporating the observed complexity of ecosystem dynamics and the prevalence of old forests. Finally, we outline a management model and demonstrate its use in forest ecosystem management and show how regional conservation area needs can be estimated. We conclude that attaining favourable conservation status in northern Europe’s boreal forests requires increasing emphasis on ecosystem management and conservation for old forest characteristics.Electronic supplementary materialThe online version of this article (10.1007/s13280-020-01444-3) contains supplementary material, which is available to authorized users. 相似文献
599.
Algal blooms and wastewater effluents can introduce algal organic matter (AOM) and effluent organic matter (EfOM) into surface waters, respectively. In this study, the impact of bromide and iodide on the formation of halogenated disinfection byproducts (DBPs) during chlorination and chloramination from various types of dissolved organic matter (DOM, e.g., natural organic matter (NOM), AOM, and EfOM) were investigated based on the data collected from literature. In general, higher formation of trihalomethanes (THMs) and haloacetic acids (HAAs) was observed in NOM than AOM and EfOM, indicating high reactivities of phenolic moieties with both chlorine and monochloramine. The formation of haloacetaldehydes (HALs), haloacetonitriles (HANs) and haloacetamides (HAMs) was much lower than THMs and HAAs. Increasing initial bromide concentrations increased the formation of THMs, HAAs, HANs, and HAMs, but not HALs. Bromine substitution factor (BSF) values of DBPs formed in chlorination decreased as specific ultraviolet absorbance (SUVA) increased. AOM favored the formation of iodinated THMs (I-THMs) during chloramination using preformed chloramines and chlorination-chloramination processes. Increasing prechlorination time can reduce the I-THM concentrations because of the conversion of iodide to iodate, but this increased the formation of chlorinated and brominated DBPs. In an analogous way, iodine substitution factor (ISF) values of I-THMs formed in chloramination decreased as SUVA values of DOM increased. Compared to chlorination, the formation of noniodinated DBPs is low in chloramination. 相似文献
600.
Yanpeng Gao Teng Guo Xiaolin Niu Na Luo Jia Chen Junlang Qiu Yuemeng Ji Guiying Li Taicheng An 《环境科学学报(英文版)》2022,34(3):72-80
As a typical class of emerging organic contaminants(EOCs), the environmental transformation and abatement of preservative parabens have raised certain environmental concerns. However, the remediation of parabens-contaminated water using natural matrixes(such as, naturally abundant minerals) is not reported extensively in literature. In this study, the transformation kinetics and the mechanism of ethylparaben using natural sphalerite(NS) were investigated. The results show that around 63% of ethy... 相似文献