全文获取类型
收费全文 | 237篇 |
免费 | 35篇 |
国内免费 | 17篇 |
专业分类
安全科学 | 14篇 |
废物处理 | 13篇 |
环保管理 | 174篇 |
综合类 | 32篇 |
基础理论 | 19篇 |
环境理论 | 1篇 |
污染及防治 | 9篇 |
评价与监测 | 7篇 |
社会与环境 | 18篇 |
灾害及防治 | 2篇 |
出版年
2023年 | 5篇 |
2022年 | 2篇 |
2021年 | 6篇 |
2020年 | 1篇 |
2019年 | 7篇 |
2018年 | 9篇 |
2017年 | 17篇 |
2016年 | 10篇 |
2015年 | 19篇 |
2014年 | 17篇 |
2013年 | 25篇 |
2012年 | 10篇 |
2011年 | 16篇 |
2010年 | 7篇 |
2009年 | 22篇 |
2008年 | 15篇 |
2007年 | 12篇 |
2006年 | 13篇 |
2005年 | 11篇 |
2004年 | 20篇 |
2003年 | 3篇 |
2002年 | 1篇 |
2001年 | 4篇 |
2000年 | 6篇 |
1999年 | 3篇 |
1998年 | 4篇 |
1997年 | 3篇 |
1996年 | 5篇 |
1995年 | 1篇 |
1994年 | 1篇 |
1993年 | 1篇 |
1990年 | 2篇 |
1988年 | 1篇 |
1987年 | 3篇 |
1986年 | 1篇 |
1984年 | 1篇 |
1980年 | 1篇 |
1979年 | 1篇 |
1975年 | 1篇 |
1973年 | 1篇 |
1972年 | 1篇 |
排序方式: 共有289条查询结果,搜索用时 62 毫秒
281.
Caitlin A. Grady Adam P. Reimer Jane Frankenberger Linda Stalker Prokopy 《Journal of the American Water Resources Association》2013,49(4):883-895
There is an increasing need to document the impacts of conservation‐related best management practices (BMPs) on water quality within a watershed. However, this impact analysis depends upon accurate geospatial locations of existing practices, which are difficult to obtain. This study demonstrates and evaluates three different methods for obtaining geospatial information for BMPs. This study was focused on the Eagle Creek Watershed, a mixed use watershed in central Indiana. We obtained geospatial information for BMPs through government records, producer interviews, and remote‐sensing aerial photo interpretation. Aerial photos were also used to validate the government records and producer interviews. This study shows the variation in results obtained from the three sources of information as well as the benefits and drawbacks of each method. Using only one method for obtaining BMP information can be incomplete, and this study demonstrates how multiple methods can be used for the most accurate picture. 相似文献
282.
Elyzabeth W. Engle 《Local Environment》2013,18(8):746-761
ABSTRACTCentral Appalachia's historical dependence on natural resource extraction industries has contributed to a long history of under- and uneven development, including trends of persistent poverty, cycles of unemployment, weakened local governance, environmental degradation, and severe social inequalities relative to the rest of the nation. Though these trends have been well documented at structural and community-levels, scholarship is more limited in assessing how the conditions of natural resource dependency may shape the everyday experiences of those who live in such regions and how those everyday experiences may illuminate challenges for future development. Employing an embedded case study design, this study examines how everyday environmental injustices may be experienced via community gardening activities, a sustainable development-oriented activity celebrated in urban locations but largely unexplored in rural environments. Drawing upon in-depth interviews with 43 gardening programme coordinators and participants, the findings demonstrate that everyday environmental injustices are experienced across four distinct, yet overlapping and mutually reinforcing, dimensions: natural, built, human health, and socioeconomic environments. These factors in turn constrain programme participation and beneficial programme outcomes, particularly for more disadvantaged households that are affected by chronic illness, geographic isolation, and environmental hazards. Although the interviewees viewed many of these challenges as further justification for pursuing grassroots initiatives like community gardening programmes, these constraints also interacted in a way that limited the success of these locally-oriented sustainable development efforts, particularly for individuals who are the most socially, economically, and environmentally marginalised. 相似文献
283.
284.
《Environmental Communication: A Journal of Nature and Culture》2013,7(4):508-528
Natural resource managers frequently make decisions in the public interest, yet research suggests managers often hold values and attitudes that differ from those of their stakeholders. Applying the co-orientation theory of communication, we contrasted beliefs of Virginia Department of Game and Inland Fisheries managers (n = 77) with those of recreational users (n = 726) of Virginia's wildlife management areas (WMAs). Although managers and users both expressed support for many of the same land management practices, managers generally expressed stronger support. Managers also more accurately predicted WMA users' beliefs on land management, compared to users' predictions of managers' beliefs. Managers and WMA users held different views about timber harvesting, which suggests it is an area with high potential for controversy and needs improved communication efforts. Frequency-based and statistical co-orientation analysis yielded different, and potentially misleading, results; thus, policy-makers should use caution when interpreting communicative situations and designing subsequent public relations efforts. 相似文献
285.
Sujay S. Kaushal Paul M. Mayer Philippe G. Vidon Rose M. Smith Michael J. Pennino Tamara A. Newcomer Shuiwang Duan Claire Welty Kenneth T. Belt 《Journal of the American Water Resources Association》2014,50(3):585-614
Nonpoint source pollution from agriculture and urbanization is increasing globally at the same time climate extremes have increased in frequency and intensity. We review >200 studies of hydrologic and gaseous fluxes and show how the interaction between land use and climate variability alters magnitude and frequency of carbon, nutrient, and greenhouse gas pulses in watersheds. Agricultural and urban watersheds respond similarly to climate variability due to headwater alteration and loss of ecosystem services to buffer runoff and temperature changes. Organic carbon concentrations/exports increase and organic carbon quality changes with runoff. Nitrogen and phosphorus exports increase during floods (sometimes by an order of magnitude) and decrease during droughts. Relationships between annual runoff and nitrogen and phosphorus exports differ across land use. CH4 and N2O pulses in riparian zones/floodplains predominantly increase with: flooding, warming, low oxygen, nutrient enrichment, and organic carbon. CH4, N2O, and CO2 pulses in streams/rivers increase due to similar factors but effects of floods are less known compared to base flow/droughts. Emerging questions include: (1) What factors influence lag times of contaminant pulses in response to extreme events? (2) What drives resistance/resilience to hydrologic and gaseous pulses? We conclude with eight recommendations for managing watershed pulses in response to interactive effects of land use and climate change. 相似文献
286.
Daniel L. Long Randel L. Dymond 《Journal of the American Water Resources Association》2014,50(4):977-987
This study examines the use of bioretention as a strategy to reduce the thermal impact associated with urban stormwater runoff in developing cold water stream watersheds. Temperature and flow data were collected during 10 controlled runs at a bioretention facility located in Blacksburg, Virginia. It was determined that bioretention has the ability to reduce the temperature of thermally charged stormwater runoff received from an asphalt surface. Significant reductions in peak and average temperatures (p < 0.001) were observed. However, this facility was unable to consistently reduce the temperature below the threshold for natural trout waters in Virginia. The ability of bioretention to reduce runoff volume and peak flow rate also serves to reduce the hydrothermal impact. An average thermal pollution reduction of nearly 37 MJ/m3 was calculated using an adopted threshold temperature of 20°C. Based on the results of this study, it was concluded that properly designed bioretention systems have the capability to reduce the thermal impact of urban stormwater runoff on cold water stream ecosystems. 相似文献
287.
On the choice of farm management practices after the reform of the Common Agricultural Policy in 2003 总被引:1,自引:0,他引:1
The Common Agricultural Policy (CAP) was fundamentally reformed in 2003. From 2005, farmers will receive decoupled income support payments instead of production premiums if basic standards for environment, food safety, animal health and welfare are met. Farmers are likely to adjust production and management practices to the new policy framework. We describe how this reform fits into the EU strategy of making agricultural production more environmentally friendly by concentrating on the financial aspects of the reforms. Using an agricultural sector model for Austria, we show that the reform will further decrease agricultural outputs, reduce farm inputs, lessen nitrogen surpluses and make environmentally friendly management practices more attractive for farmers. 相似文献
288.
California’s population increased 25% between 1980 and 1990, resulting in rapid and extensive urbanization. Of a total 123,000
ha urbanized in 42 of the state’s 58 counties between 1984 and 1990, an estimated 13% occurred on irrigated prime farmland,
and 48% on wildlands or fallow marginal farmlands. Sixty-six percent of all new irrigated farmland put into production between
1984 and 1990 was of lesser quality than the prime farmland taken out of production by urbanization. Factors dictating the
agricultural development of marginal farmlands include the availability and price of water and land, agricultural commodity
prices, and technical innovations such as drip irrigation systems that impact the feasibility and costs of production. The
increasing amount of marginal farmland being put into production could have significant water quality consequences because
marginal lands are generally steeper, have more erodible soils, poorer drainage, and require more fertilizer than prime farmlands.
Although no data exist to test our hypothesis, and numerous variables preclude definitive predictions, the evidence suggests
that new irrigated marginal lands can increase nonpoint source (NPS) pollution for a given size area by an order of magnitude
in some cases. 相似文献
289.
One of the most challenging issues in the field of sustainable design is that of limiting the environmental impact of structural systems, as they contribute significantly to raw material consumption, global carbon emissions and solid waste production. This paper addresses the approach of the reuse of steel structure without melting which allows for savings in steel mass and the reduction of waste amounts offering moreover an opportunity to avoid environmental burdens related to the recycling process. Recent studies have stressed the technical feasibility of this strategy, which appears particularly effective in those countries in which a building's life is rather short, such as in Japan and US, though its application encounters more difficulties in most European countries, owing to longer building use. Besides stressing the architectural and structural feasibility of the above-mentioned strategy, this research work aims to quantify the mass savings that are achievable in this manner by presenting a real case study set in Italy. It consists in a railway station, which has been designed keeping in mind the partial employment of structural elements recovered from an old industrial building that is no longer in use. To estimate the amount of steel saved, two different structural models for the designed building have been carried out and compared. In the first one, the structure has been designed on the assumption of the reusing of recovered structural elements; in the second one, the same structure has been designed considering the use of new elements only. The final result of the analysis shows that steel reuse allowed for savings of up to 30% of steel. 相似文献