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991.
Extensive research has been conducted globally into conceptual frameworks for ecosystem services, the most notable being the
Millennium Ecosystem Assessment (Millennium ecosystem assessment: ecosystems and human well-being; a framework for assessment.
World Resources Institute, Washington, DC, pp 51, 53–55, 2005). The South East Queensland (SEQ) Ecosystem Services Framework (Australia) aims to provide the tools to enable government,
industry, business, researchers, non-government organizations and land managers to apply the concept of ecosystem services
in their planning and management practices. This article describes the Framework and the process that has produced matrices
and maps that identify and illustrate the linkages between ecosystems, ecosystem functions, ecosystem services and the community’s
well-being. The matrices and maps derived can identify areas in the region where the most ecosystem services are generated.
This allows areas to be considered as valuable natural assets of the region, deserving appropriate protection measures or
significant offsets if they are diminished or degraded in any way. Although the Framework requires further refinement and
ongoing development, the process applied and the products produced has enabled decision makers to turn the concept of ecosystem
services into practical application in SEQ. 相似文献
992.
Lizhu Wang Kevin Wehrly James E. Breck Lidia Szabo Kraft 《Environmental management》2010,46(3):471-483
Assessment of lake impairment status and identification of threats’ type and source is essential for protection of intact,
enhancement of modified, and restoration of impaired lakes. For regions in which large numbers of lakes occur, such assessment
has usually been done for only small fractions of lakes due to resource and time limitation. This study describes a process
for assessing lake impairment status and identifying which human disturbances have the greatest impact on each lake for all
lakes that are 2 ha or larger in the state of Michigan using readily available, georeferenced natural and human disturbance
databases. In-lake indicators of impairment are available for only a small subset of lakes in Michigan. Using statistical
relationships between the in-lake indicators and landscape natural and human-induced measures from the subset lakes, we assessed
the likely human impairment condition of lakes for which in-lake indicator data were unavailable using landscape natural and
human disturbance measures. Approximately 92% of lakes in Michigan were identified as being least to marginally impacted and
about 8% were moderately to heavily impacted by landscape human disturbances. Among lakes that were heavily impacted, more
inline lakes (92%) were impacted by human disturbances than disconnected (6%) or headwater lakes (2%). More small lakes were
impacted than medium to large lakes. For inline lakes, 90% of the heavily impacted lakes were less than 40 ha, 10% were between
40 and 405 ha, and 1% was greater than 405 ha. For disconnected and headwater lakes, all of the heavily impacted lakes were
less than 40 ha. Among the anthropogenic disturbances that contributed the most to lake disturbance index scores, nutrient
yields and farm animal density affected the highest number of lakes, agricultural land use affected a moderate number of lakes,
and point-source pollution and road measures affected least number of lakes. Our process for assessing lake condition represents
a significant advantage over other routinely used methods. It permits the evaluation of lake condition across large regions
and yields an overall disturbance index that is a physicochemical and biological indicator weighted sum of multiple disturbance
factors. The robustness of our approach can be improved with increased availability of high-resolution disturbance datasets. 相似文献
993.
James S. Gruber 《Environmental management》2010,45(1):52-66
This article examines recent research on approaches to community-based environmental and natural resource management and reviews
the commonalities and differences between these interdisciplinary and multistakeholder initiatives. To identify the most effective
characteristics of Community-based natural resource management (CBNRM), I collected a multiplicity of perspectives from research
teams and then grouped findings into a matrix of organizational principles and key characteristics. The matrix was initially
vetted (or “field tested”) by applying numerous case studies that were previously submitted to the World Bank International
Workshop on CBNRM. These practitioner case studies were then compared and contrasted with the findings of the research teams.
It is hoped that the developed matrix may be useful to researchers in further focusing research, understanding core characteristics
of effective and sustainable CBNRM, providing practitioners with a framework for developing new CBNRM initiatives for managing
the commons, and providing a potential resource for academic institutions during their evaluation of their practitioner-focused
environmental management and leadership curriculum. 相似文献
994.
Josephine Molin James Mueller Donald Hanson Troy Fowler Tim Skrotzki 《补救:环境净化治理成本、技术与工艺杂志》2010,20(3):51-62
Groundwater at the former Serry's Dry Cleaning site in Corvallis, Oregon, was impacted by chlorinated volatile organic compounds (CVOCs). The primary CVOCs impacting the site include tetrachloroethene, trichloroethene, dichloroethene, and vinyl chloride, which were detected at concentrations up to 22,000, 1,700, 3,100, and 7 μg/L, respectively, prior to treatment. Large seasonal fluctuations in groundwater CVOC concentrations indicated that a significant fraction of the CVOC mass was present in the smear zone. Field‐scale pilot tests were performed for the Oregon Department of Environmental Quality's Dry Cleaner Program to evaluate the performance of EHC® in situ chemical reduction (ISCR) technology. The pilot study involved evaluating field performance and physical distribution into low‐permeability soil using basic Geoprobe® injection tooling. The testing results confirmed that bioremediation enhanced by ISCR supported long‐term treatment at the site. This article describes the implementation and results of the tests. Performance data are available from a three‐year period following the injections, allowing for a discussion about sustained performance and reagent longevity. © 2010 Wiley Periodicals, Inc. 相似文献
995.
Remediation of chlorinated solvent DNAPL sites often meets with mixed results. This can be attributed to the diametrically opposed nature of the impacts, where the disparate dissolved‐phase plume is more manageable than the localized, high‐concentration source area. A wide range of technologies are available for downgradient plume management, but the relative mass of contaminants in a DNAPL source area generally requires treatment for such technologies to be effective over the long term. In many cases, the characteristics of DNAPL source zones (e.g., depth, soil heterogeneity, structural limitations) limit the available options. The following describes the successful full‐scale implementation of in situ chemical reduction (ISCR) enhanced bioremediation of a TCE DNAPL source zone. In this demonstration, concentrations of TCE were rapidly reduced to below the maximum contaminant level (MCL) in less than six months following implementation. The results described herein suggest that ISCR‐enhanced bioremediation is a viable remedial alternative for chlorinated solvent source zones. © 2010 Wiley Periodicals, Inc. 相似文献
996.
James F. Fox Charles M. Davis Darren K. Martin 《Journal of the American Water Resources Association》2010,46(6):1192-1204
Fox, James F., Charles M. Davis, and Darren K. Martin, 2010. Sediment Source Assessment in a Lowland Watershed Using Nitrogen Stable Isotopes. Journal of the American Water Resources Association (JAWRA) 46(6):1192–1204. DOI: 10.1111/j.1752-1688.2010.00485.x Abstract: Sediment sources and transported sediments were sampled in a lowland watershed with pronounced fine sediment storage in the streambed. Sediments were analyzed for carbon and nitrogen content and stable nitrogen isotopic composition. Analysis of the data shows that temporarily stored streambed sediments dominate the sediment load during moderate- and low-flow hydrologic events. Modeling of sediment transport and nitrogen elemental and isotopic mass balance was performed for the watershed for a 12-month time period using a continuous, conceptual-based model. The model results show that during moderate- and low-flow hydrologic events, the streambed is slowly downcutting. During very high-flow hydrologic events, deposition is pronounced in the streambed and sediment is replenished to the bed. Nitrogen model results show that elemental and isotopic nitrogen of streambed sediments vary substantially over the simulation period. In this manner, the streambed in a lowland watershed functions as a temporary storage zone that, in turn, can impact the nitrogen elemental and isotopic signature of sediments. The variation could significantly impact estimates of sediment provenance using nitrogen tracer-based methods. Future work should consider both hydrologic and biogeochemical control on the nitrogen isotopic signature of sediments in small lowland watersheds and streams where a significant portion of deposited fines are temporarily stored. 相似文献
997.
Jochen Stutz Kam Weng Wong Laura Lawrence Luke Ziemba James H. Flynn Bernhard Rappenglück Barry Lefer 《Atmospheric environment (Oxford, England : 1994)》2010,44(33):4099-4106
Radical chemistry in the nocturnal urban boundary layer is dominated by the nitrate radical, NO3, which oxidizes hydrocarbons and, through the aerosol uptake of N2O5, indirectly influences the nitrogen budget. The impact of NO3 chemistry on polluted atmospheres and urban air quality is, however, not well understood, due to a lack of observations and the strong impact of vertical stability of the boundary layer, which makes nocturnal chemistry highly altitude dependent.Here we present long-path DOAS observations of the vertical distribution of the key nocturnal species O3, NO2, and NO3 during the TRAMP experiment in Summer 2006 in Houston, TX. Our observations confirm the altitude dependence of nocturnal chemistry, which is reflected in the concentration profiles of all trace gases at night. In contrast to other study locations, NO3 chemistry in Houston is dominated by industrial emissions of alkenes, in particular of isoprene, isobutene, and sporadically 1,3-butadiene, which are responsible for more than 70% of the nocturnal NO3 loss. The nocturnally averaged loss of NOx in the lowest 300 m of the Houston atmosphere is ~0.9 ppb h?1, with little day-to-day variability. A comparison with the daytime NOx loss shows that NO3 chemistry is responsible for 16–50% of the NOx loss in a 24-h period in the lowest 300 m of the atmosphere. The importance of the NO3 + isoprene/1,3-butadiene reactions implies the efficient formation of organic nitrates and secondary organic aerosol at night in Houston. 相似文献
998.
Jung KH Patel MM Moors K Kinney PL Chillrud SN Whyatt R Hoepner L Garfinkel R Yan B Ross J Camann D Perera FP Miller RL 《Atmospheric environment (Oxford, England : 1994)》2010,44(36):4545-4552
Exposure to air pollutants has been associated with adverse health effects. However, analyses of the effects of season and ambient parameters such as ozone have not been fully conducted. Residential indoor and outdoor air levels of polycyclic aromatic hydrocarbons (PAH), black carbon (measured as absorption coefficient [Abs]), and fine particulate matter <2.5 μm (PM)(2.5) were measured over two-weeks in a cohort of 5-6 year old children (n=334) living in New York City's Northern Manhattan and the Bronx between October 2005 and April 2010. The objectives were to: 1) characterize seasonal changes in indoor and outdoor levels and indoor/outdoor (I/O) ratios of PAH (gas + particulate phase; dichotomized into Σ(8)PAH(semivolatile) (MW 178-206), and Σ(8)PAH(nonvolatile) (MW 228-278)), Abs, and PM(2.5); and 2) assess the relationship between PAH and ozone. Results showed that heating compared to nonheating season was associated with greater Σ(8)PAH(nonvolatile) (p<0.001) and Abs (p<0.05), and lower levels of Σ(8)PAH(semivolatile) (p<0.001). In addition, the heating season was associated with lower I/O ratios of Σ(8)PAH(nonvolatile) and higher I/O ratios of Σ(8)PAH(semivolatile) (p<0.001) compared to the nonheating season. In outdoor air, Σ(8)PAH(nonvolatile) was correlated negatively with community-wide ozone concentration (p<0.001). Seasonal changes in emission sources, air exchanges, meteorological conditions and photochemical/chemical degradation reactions are discussed in relationship to the observed seasonal trends. 相似文献
999.
Elizabeth A. Stone Curtis J. Hedman Jiabin Zhou Mark Mieritz James J. Schauer 《Atmospheric environment (Oxford, England : 1994)》2010,44(3):312-319
This study targets understanding the secondary sources of organic aerosol in Mexico City during the Megacities Impact on Regional and Global Environment (MIRAGE) 2006 field campaign. Ambient PM2.5 was collected daily at urban and peripheral locations. Particle-phase secondary organic aerosol (SOA) products of anthropogenic and biogenic precursor gases were measured by gas chromatography mass spectrometry. Ambient concentrations of SOA tracers were used to estimate organic carbon (OC) from secondary origins (SOC). Anthropogenic SOC was estimated as 20–25% of ambient OC at both sites, while biogenic SOC was less abundant, but was relatively twice as important at the peripheral site. The OC that was not attributed secondary sources or to primary sources in a previous study showed temporal consistency with biomass-burning events, suggesting the importance of secondary processing of biomass-burning emissions in the region. The best estimate of biomass-burning-related SOC was in the range of 20–30% of ambient OC during peak biomass burning events. Low-molecular weight (MW) alkanoic and alkenoic dicarboxylic acids (C2–C5) were also measured, of which oxalic acid was the most abundant. The spatial and temporal trends of oxalic acid differed from tracers for primary and secondary sources, suggesting that it had different and/or multiple sources in the atmosphere. 相似文献
1000.
The ever-increasing complexity of disasters demands utilisation of knowledge that exists outside domains traditionally drawn upon in disaster management. To be operationally useful, such knowledge must he extracted, combined with information generated by the disaster itself, and transformed into actionable knowledge. The process, though, is hampered by existing, business-oriented approaches to knowledge management, by technical issues related to access to relevant, multi-domain information/knowledge, and by executive decision-making processes based predominantly on historical knowledge. Consequently, as shown by many recent incidents, the management of large-scale (mega) disasters is often inefficient and exceedingly costly. This paper demonstrates that the integration of modified information and knowledge management into the concepts of network-centric operations and network-enabled capabilities, and the employment of Boyd's OODA (Observe, Orient, Decide, and Act) Loop-based decision-making in unpredictable and dynamically changing environments, may address some of these problems. 相似文献