全文获取类型
收费全文 | 220篇 |
免费 | 9篇 |
国内免费 | 2篇 |
专业分类
安全科学 | 7篇 |
废物处理 | 8篇 |
环保管理 | 44篇 |
综合类 | 45篇 |
基础理论 | 65篇 |
环境理论 | 1篇 |
污染及防治 | 34篇 |
评价与监测 | 10篇 |
社会与环境 | 8篇 |
灾害及防治 | 9篇 |
出版年
2023年 | 5篇 |
2022年 | 8篇 |
2021年 | 6篇 |
2020年 | 7篇 |
2019年 | 15篇 |
2018年 | 8篇 |
2017年 | 12篇 |
2016年 | 10篇 |
2015年 | 17篇 |
2014年 | 12篇 |
2013年 | 17篇 |
2012年 | 8篇 |
2011年 | 21篇 |
2010年 | 8篇 |
2009年 | 9篇 |
2008年 | 11篇 |
2007年 | 4篇 |
2006年 | 6篇 |
2005年 | 2篇 |
2004年 | 7篇 |
2003年 | 5篇 |
2002年 | 8篇 |
2001年 | 5篇 |
2000年 | 7篇 |
1999年 | 3篇 |
1998年 | 1篇 |
1997年 | 1篇 |
1995年 | 1篇 |
1994年 | 1篇 |
1992年 | 2篇 |
1982年 | 1篇 |
1981年 | 3篇 |
排序方式: 共有231条查询结果,搜索用时 15 毫秒
181.
182.
The promising spread of sustainable agriculture in Asia 总被引:1,自引:0,他引:1
Despite great successes in increasing food production, Asia still faces enormous food security challenges. Most commentators agree that there will have to be increases in food production from existing agricultural land, but many are pessimistic about the future, judging likelihood of success on the basis of past performance of 'modern' agricultural development. Sustainable agriculture, though, offers entirely new opportunities, by emphasising the productive values of natural, social and human capital, all assets that Asian countries either have in abundance or that can be regenerated at relatively low financial cost.
This paper sets out an assets-based model of agricultural systems, together with a typology of eight approaches for sustainable agriculture improvements. In the 16 projects/initiatives spread across eight countries that are analysed, some 2.86 million households have substantially improved total food production on 4.93 million hectares, resulting in greatly improved household food security. Proportional yield increases are greatest in rainfed systems, but irrigated systems have seen small cereal yield increases combined with added production from additional productive system components (such as fish in rice, vegetables on dykes). The additional positive impacts on natural, social and human capital are also helping to build the assets base so as to sustain these improvements in the future.
This analysis indicates that sustainable agriculture can deliver large increases in food production in Asia. But spreading these to much larger numbers of farm households will not be easy. It will require fundamental policy reform. 相似文献
This paper sets out an assets-based model of agricultural systems, together with a typology of eight approaches for sustainable agriculture improvements. In the 16 projects/initiatives spread across eight countries that are analysed, some 2.86 million households have substantially improved total food production on 4.93 million hectares, resulting in greatly improved household food security. Proportional yield increases are greatest in rainfed systems, but irrigated systems have seen small cereal yield increases combined with added production from additional productive system components (such as fish in rice, vegetables on dykes). The additional positive impacts on natural, social and human capital are also helping to build the assets base so as to sustain these improvements in the future.
This analysis indicates that sustainable agriculture can deliver large increases in food production in Asia. But spreading these to much larger numbers of farm households will not be easy. It will require fundamental policy reform. 相似文献
183.
Back-pedaling or continuing quietly? Assessing the impact of ICLEI membership termination on cities’ sustainability actions 总被引:1,自引:0,他引:1
Over the past decade, cities have emerged as leaders in sustainability and climate protection in the United States. ICLEI, a voluntary network of local governments, played an important role driving this trend. After years of steady growth, ICLEI became a target of political opposition and its membership dropped significantly from 2010 to 2012. This begs the question of whether cities’ termination of their ICLEI affiliation diminishes their implementation of sustainability actions. Two surveys administered in 2010 and 2014 provide data on cities’ implementation of an array of sustainability actions. Using a difference-in-differences (DiD) method, the impact of ICLEI termination on local governments’ administrative and policy commitments to sustainability is assessed. The results suggest that ending ICLEI membership does not significantly impact local sustainability actions, and also indicate that the durability of policy actions may be only loosely linked to the policies that justify them. 相似文献
184.
Rachel Freeman Chris McMahon Patrick Godfrey 《International Journal of Sustainable Engineering》2017,10(4-5):260-271
AbstractRe-distributed manufacturing (RDM), broadly described as manufacturing done at a smaller-scale and locally, could be beneficial to business and urban society through creating jobs, reducing the environmental impacts of production, and improving resilience to future disturbances. Consideration of RDM within a city-region requires the consideration of a wide range of issues – societal, technical, economic and environmental. This paper presents the results of a study into the potential for RDM to contribute to a sustainable, resilient city in the face of a range of expected future disturbances on the city and on manufacturing sectors. The study took an integrated assessment approach which incorporated the development of a conceptual framework; a ‘strawman’ causal loop diagram which was reviewed by participants in a workshop; and a stock and flow system dynamics model that represents our understanding about the structure and behaviour of urban manufacturing. Several key themes emerged: similarities between RDM and traditional manufacturing, availability of physical space for RDM to be done, achieving urban resilience through RDM by enabling responsiveness to disturbances, changes in environmental impacts from production, additions or losses in jobs, the competitiveness of local manufacturing, and skills and innovation for RDM technologies. Further work is recommended. 相似文献
185.
186.
Restoration of foundation species promises to reverse environmental degradation and return lost ecosystem services, but a lack of standardized evaluation across projects limits understanding of recovery, especially in marine systems. Oyster reefs are restored to reverse massive global declines and reclaim valuable ecosystem services, but the success of these projects has not been systematically and comprehensively quantified. We synthesized data on ecosystem services associated with oyster restoration from 245 pairs of restored and degraded reefs and 136 pairs of restored and reference reefs across 3500 km of U.S. Gulf of Mexico and Atlantic coastlines. On average, restoration was associated with a 21-fold increase in oyster production (mean log response ratio = 3.08 [95% confidence interval: 2.58–3.58]), 34–97% enhancement of habitat provisioning (mean community abundance = 0.51 [0.41–0.61], mean richness = 0.29 [0.19–0.39], and mean biomass = 0.69 [0.39–0.99]), 54% more nitrogen removal (mean = 0.43 [0.13–0.73]), and 89–95% greater sediment nutrients (mean = 0.67 [0.27–1.07]) and organic matter (mean = 0.64 [0.44–0.84]) relative to degraded habitats. Moreover, restored reefs matched reference reefs for these ecosystem services. Our results support the continued and expanded use of oyster restoration to enhance ecosystem services of degraded coastal systems and match many functions provided by reference reefs. 相似文献
187.
Richard Schuster Rachel Buxton Jeffrey O. Hanson Allison D. Binley Jeremy Pittman Vivitskaia Tulloch Frank A. La Sorte Patrick R. Roehrdanz Peter H. Verburg Amanda D. Rodewald Scott Wilson Hugh P. Possingham Joseph R. Bennett 《Conservation biology》2023,37(3):e14048
Protected areas are a key instrument for conservation. Despite this, they are vulnerable to risks associated with weak governance, land-use intensification, and climate change. We used a novel hierarchical optimization approach to identify priority areas for expanding the global protected area system that explicitly accounted for such risks while maximizing protection of all known terrestrial vertebrate species. To incorporate risk categories, we built on the minimum set problem, where the objective is to reach species distribution protection targets while accounting for 1 constraint, such as land cost or area. We expanded this approach to include multiple objectives accounting for risk in the problem formulation by treating each risk layer as a separate objective in the problem formulation. Reducing exposure to these risks required expanding the area of the global protected area system by 1.6% while still meeting conservation targets. Incorporating risks from weak governance drove the greatest changes in spatial priorities for protection, and incorporating risks from climate change required the largest increase (2.52%) in global protected area. Conserving wide-ranging species required countries with relatively strong governance to protect more land when they bordered nations with comparatively weak governance. Our results underscore the need for cross-jurisdictional coordination and demonstrate how risk can be efficiently incorporated into conservation planning. Planeación de las áreas protegidas para conservar la biodiversidad en un futuro incierto 相似文献
188.
Rachel T. Noble John H. Dorsey Molly Leecaster Victoria Orozco-Borbón Daniel Reid Kenneth Schiff Stephen B. Weisberg 《Environmental monitoring and assessment》2000,64(1):435-447
A regional survey of the microbiological water quality along the shoreline of the Southern California Bight (SCB), from Point Conception south to Ensenada, Mexico, was conducted during August, 1998, by 36 agencies under the coordination of the Southern California Coastal Water Research Project (SCCWRP). Microbiological water quality was assessed by calculating the percentage of shoreline-mile-days that exceeded bacterial indicator thresholds for total and fecal coliforms, total/fecal ratios, and enterococci. Sample sites were selected using a stratified random sampling approach, with the SCB recreational shoreline divided into six strata: high- and low-use sandy beaches, high- and low-use rocky shoreline, and perennial and ephemeral freshwater outlets. Samples were collected on a weekly basis at a total of 253 sites, beginning on August 2nd, 1998 and continuing for five weeks. Samples were analyzed by 22 participating labs using their normal methods (multiple tube fermentation, membrane filtration, Colilert® and/or Enterolert®). All labs met testing criteria established through intercalibration exercises and quality control check samples distributed during the sampling period. Nearly 95% of the shoreline-mile days did not exceed daily and monthly bacterial indicator thresholds, demonstrating good bacteriological water quality along the SCB shoreline. Freshwater outlets, comprised mainly of storm drains, had the poorest water quality with 60% and 40% of the shoreline-miles exceeding monthly and daily thresholds, respectively. Freshwater outlets were also more likely to demonstrate exceedances by multiple indicators at a single site, and repeat exceedances at sites over the five-week period. Compared with the southern California beaches, Mexican beaches had nearly 5 times the number of exceedances for total and fecal coliforms, and nearly 8 times the number of exceedances for total/fecal ratios. 相似文献
189.
Otto Ilona M. Reckien Diana Reyer Christopher P. O. Marcus Rachel Le Masson Virginie Jones Lindsey Norton Andrew Serdeczny Olivia 《Regional Environmental Change》2017,17(6):1651-1662
Regional Environmental Change - This article provides a review of recent scientific literature on social vulnerability to climate change, aiming to determine which social and demographic groups,... 相似文献
190.