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101.
The present US Federal wetland management strategy under Section 404 of the Clean Water Act does not account for the differences in the natural values of wetlands and their different vulnerability to development pressure. The strategy, aimed at reducing the regulatory burden, provides for different levels of wetland protection, primarily by designating certain activities in or affecting wetlands as essentially harmless, having only minor impacts even when considered for their cumulative effects. Such activities are authorized under general permits precluding any evaluation of project impacts. A sounder, yet practical, rationale for wetland management and regulatory relief should be linked to the scarcity of certain wetland habitats, the habitat diversity or carrying capacity, the degree of degradation from past development, and the incremental losses already incurred within the same wetland ecosystem. The regulatory effort should be concentrated where these characteristics indicate high-value wetlands.Wetland impacts appear to fit into five basic orders of magnitude; these pertain to the relative cost and difficulty of impact mitigation. Up to 13 ecological and public-interest variables can modify the seriousness of the basic impact. Together, the basic orders of impact and modifying variables describe the theoretical framework for wetland management. However, a practical rationale for better wetland management must be constrained to factors not requiring a field investigation in advance of project planning for construction and development.This article was produced in part from work funded by the Office of Technology Assessment (OTA) of the United States Congress for use in its study, Wetlands: Their Use and Regulation. The views expressed do not necessarily represent those of OTA. 相似文献
102.
In those states that have not included CWM as hazardous materials in their RCRA programs, the RCRA requirements for management
of hazardous waste would not strictly apply to any of the CWM. The Army has historically implemented procedures requiring
that chemical warfare agents be managed as RCRA hazardous waste regardless of the concentration, physical form, or configuration
of the agent. Such application of strict hazardous waste requirements to management of potentially nonhazardous CWM can result
in remedial costs well out of proportion to potential human health and environmental benefits. Recent development of chronic
toxicity values for the CWM has opened the door for development of cleanup and waste management standards for waste streams
or media containing small residual amounts of CWM. Implementation of this health-based approach to management of CWM remediation
wastes may, in part, help to reduce potentially unnecessary hazardous waste management costs for the nonhazardous CWM. 相似文献
103.
李纪恩 《防灾科技学院学报》2011,13(3):92-96
随着经济社会和防震减灾事业的发展,特别是《突发事件应对法》的发布实施和《防震减灾法》的修订,曾经为加强和规范地震应急管理,推进防震减灾事业全面发展,发挥了重要的制度保障作用的《破坏性地震应急条例》,在实施过程中出现了一些明显不适应的地方,对条例进行修订已迫在眉睫。本文阐述了条例修订的基本原则和意义,并就应急机构、应急预... 相似文献
104.
Characterizing the Extent of Spatially Integrated Floodplain and Wetland Systems in the White River,Indiana, USA
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C. R. Lane A. Hall E. D'Amico N. Sangwan V. Merwade 《Journal of the American Water Resources Association》2017,53(4):774-790
Floodplain delineation may inform protection of wetland systems under local, state, or federal laws. Nationally available Federal Emergency Management Agency Flood Insurance Rate Maps (FIRMs, “100‐year floodplain” maps) focus on urban areas and higher‐order river systems, limiting utility at large scales. Few other national‐scale floodplain data are available. We acquired FIRMs for a large watershed and compared FIRMs to floodplain and integrated wetland area mapping methods based on (1) geospatial distance, (2) geomorphic setting, and (3) soil characteristics. We used observed flooding events (OFEs) with recurrence intervals of 25‐50 to >100 years to assess floodplain estimate accuracy. FIRMs accurately reflected floodplain areas based on OFEs and covered 32% of river length, whereas soil‐based mapping was not as accurate as FIRMs but characterized floodplain areas over approximately 65% of stream length. Geomorphic approaches included more areas than indicated by OFE, whereas geospatial approaches tended to cover less area. Overall, soil‐based methods have the highest utility in determining floodplains and their integrated wetland areas at large scales due to the use of nationally available data and flexibility for regional application. These findings will improve floodplain and integrated wetland system extent assessment for better management at local, state, and national scales. 相似文献
105.
MICHAEL R. BOSWELL ROBERT E. DEYLE RICHARD A. SMITH E. JAY BAKER 《Environmental management》1999,23(3):359-372
/ A method is presented for estimating probable public costs resulting from damage caused by hurricanes, measured as local government expenditures approved for reimbursement under the Stafford Act Section 406 Public Assistance Program. The method employs a multivariate model developed through multiple regression analysis of an array of independent variables that measure meteorological, socioeconomic, and physical conditions related to the landfall of hurricanes within a local government jurisdiction. From the regression analysis we chose a log-log (base 10) model that explains 74% of the variance in the expenditure data using population and wind speed as predictors. We illustrate application of the method for a local jurisdiction-Lee County, Florida, USA. The results show that potential public costs range from $4.7 million for a category 1 hurricane with winds of 137 kilometers per hour (85 miles per hour) to $130 million for a category 5 hurricane with winds of 265 kilometers per hour (165 miles per hour). Based on these figures, we estimate expected annual public costs of $2.3 million. These cost estimates: (1) provide useful guidance for anticipating the magnitude of the federal, state, and local expenditures that would be required for the array of possible hurricanes that could affect that jurisdiction; (2) allow policy makers to assess the implications of alternative federal and state policies for providing public assistance to jurisdictions that experience hurricane damage; and (3) provide information needed to develop a contingency fund or other financial mechanism for assuring that the community has sufficient funds available to meet its obligations. KEY WORDS: Hurricane; Public costs; Local government; Disaster recovery; Disaster response; Florida; Stafford Act 相似文献
106.
This study evaluated the impact of small boat traffic on reaction distances of Marbled Murrelets (Brachyramphus marmoratus), in the marine waters of Pacific Rim National Park Reserve, British Columbia, Canada. Observers on moving boats recorded the minimum distance the boat came to murrelets on the water, and any disturbance reaction (fly, dive, no reaction). Out of the 7500 interactions 11.7% flew, 30.8% dove and 58.1% exhibited no flushing reaction. Using a product-limit analysis, we developed curves for the proportion of Marbled Murrelets flushing (dive or flight) as a function of reaction distance. Overall, the majority of Marbled Murrelets waited until boats were within 40 m before reacting, with 25% of the population reacting at 29.2m. A stepwise Cox regression indicated that age, boat speed, and boat density (loaded in that order), significantly affected flushing response. More juveniles flushed than adults (70.1 versus 51.7%), but at closer distances. Faster boats caused a greater proportion of birds to flush, and at further distances (25% of birds flushed at 40 m at speeds > 29 kph versus 28m at speeds <12kph). A stepwise logistic regression on diving and flight responses indicated that birds tended to fly completely out of feeding areas at the approach of boats travelling >28.8 kph and later in the season (July and August). Other secondary variables included; boat density and time of day. Discussion focused on possible management actions such as the application of speed limits, set back distances, and exclusion of boat traffic to protect Marbled Murrelets. 相似文献
107.
Douglas J. Norton James D. Wickham Timothy G. Wade Kelly Kunert John V. Thomas Paul Zeph 《Environmental management》2009,44(2):356-368
Common decision support tools and a growing body of knowledge about ecological recovery can help inform and guide large state
and federal restoration programs affecting thousands of impaired waters. Under the federal Clean Water Act (CWA), waters not
meeting state Water Quality Standards due to impairment by pollutants are placed on the CWA Section 303(d) list, scheduled
for Total Maximum Daily Load (TMDL) development, and ultimately restored. Tens of thousands of 303(d)-listed waters, many
with completed TMDLs, represent a restoration workload of many years. State TMDL scheduling and implementation decisions influence
the choice of waters and the sequence of restoration. Strategies that compare these waters’ recovery potential could optimize
the gain of ecological resources by restoring promising sites earlier. We explored ways for states to use recovery potential
in restoration priority setting with landscape analysis methods, geographic data, and impaired waters monitoring data. From
the literature and practice we identified measurable, recovery-relevant ecological, stressor, and social context metrics and
developed a restorability screening approach adaptable to widely different environments and program goals. In this paper we
describe the indicators, the methodology, and three statewide, recovery-based targeting and prioritization projects. We also
call for refining the scientific basis for estimating recovery potential.
相似文献
Paul ZephEmail: |
108.
Michael E. Beyer 《Environmental Forensics》2015,16(2):186-202
Critical subset allocation (CSA) is a methodology for allocating remediation costs at sites where multiple contaminants contribute to the exceedance of multiple regulatory risk standards. The basic unit of allocation in CSA is the critical subset, which is a subset of potentially responsible parties (PRPs) that meets two criteria: 1) the risks associated with the subset exceed at least one regulatory risk standard; and 2) at least one of the PRPs in the subset is individually necessary for the first criterion to be true. Each PRP is assigned an allocation score equal to the number of critical subsets for which that PRP is an individually necessary member. The allocation share of a PRP is equal to its allocation score divided by the sum of all PRP allocation scores. 相似文献
109.
110.
A significant limitation in biodiversity conservation has been the effective implementation of laws and regulations that protect species’ habitats from degradation. Flexible, efficient, and effective monitoring and enforcement methods are needed to help conservation policies realize their full benefit. As remote sensing data become more numerous and accessible, they can be used to identify and quantify land-cover changes and habitat loss. However, these data remain underused for systematic conservation monitoring in part because of a lack of simple tools. We adapted 2 algorithms that automatically identify differences between pairs of images. We used free, publicly available satellite data to evaluate their ability to rapidly detect land-cover changes in a variety of land-cover types. We compared algorithm predictions with ground-truthed results at 100 sites of known change in the United States. We also compared algorithm predictions to manually created polygons delineating anthropogenic change in 4 case studies involving imperiled species’ habitat: oil and gas development in the range of the Greater Sage Grouse (Centrocercus urophasianus); sand mining operations in the range of the dunes sagebrush lizard (Sceloporus arenicolus); loss of Piping Plover (Charadrius melodus) coastal habitat after Hurricane Michael (2018); and residential development in St. Andrew beach mouse (Peromyscus polionotus peninsularis) habitat. Both algorithms effectively discriminated between pixels corresponding to land-cover change and unchanged pixels as indicated by area under a receiver operating characteristic curve >0.90. The algorithm that was most effective differed among the case-study habitat types, and both effectively delineated habitat loss as indicated by low omission (min. = 0.0) and commission (min. = 0.0) rates, and moderate polygon overlap (max. = 47%). Our results showed how these algorithms can be used to help close the implementation gap of monitoring and enforcement in biodiversity conservation. We provide a free online tool that can be used to run these analyses ( https://conservationist.io/habitatpatrol ). 相似文献