全文获取类型
收费全文 | 83篇 |
免费 | 0篇 |
国内免费 | 3篇 |
专业分类
废物处理 | 3篇 |
环保管理 | 2篇 |
综合类 | 53篇 |
基础理论 | 14篇 |
污染及防治 | 9篇 |
评价与监测 | 3篇 |
社会与环境 | 2篇 |
出版年
2021年 | 3篇 |
2019年 | 1篇 |
2018年 | 5篇 |
2017年 | 3篇 |
2016年 | 2篇 |
2015年 | 5篇 |
2014年 | 8篇 |
2013年 | 5篇 |
2012年 | 5篇 |
2011年 | 4篇 |
2010年 | 8篇 |
2009年 | 1篇 |
2008年 | 5篇 |
2007年 | 2篇 |
2006年 | 1篇 |
2005年 | 3篇 |
2004年 | 2篇 |
2002年 | 2篇 |
1999年 | 3篇 |
1998年 | 1篇 |
1988年 | 1篇 |
1965年 | 4篇 |
1963年 | 1篇 |
1962年 | 1篇 |
1961年 | 1篇 |
1954年 | 2篇 |
1950年 | 2篇 |
1946年 | 1篇 |
1934年 | 1篇 |
1916年 | 1篇 |
1913年 | 2篇 |
排序方式: 共有86条查询结果,搜索用时 500 毫秒
51.
Eduard Ariza Jose A. Jimenez Rafael Sarda Miriam Villares Josep Pinto Rosa Fraguell Elisabet Roca Carolina Marti Herminia Valdemoro Ramon Ballester Modest Fluvia 《Environmental management》2010,45(5):998-1013
A composite index, based on function analysis and including thirteen sub-indices, was developed to assess the overall quality of urban and urbanized beaches in the Mediterranean area. The aggregation of components and sub-indices was based on two questionnaires completed by beach users and experts. Applying the new Beach Quality Index (BQI) demonstrated that the quality of beaches could be improved. In general, the strongest aspects of the beaches assessed were those related to short-term user demand, and the weakest were those related to the consequences of human pressure on the area, in particular, erosion problems. The composite index is intended to be used together with Environmental Management Beach Systems (EMBs) as a hierarchical management scorecard and in monitoring programs. This new tool could also make planning more proactive by synthesizing the state of the most important beach processes. 相似文献
52.
Zhiqiang Zhang Shengping Wang Ge Sun Steven G. McNulty Huayong Zhang Jianlao Li Manliang Zhang Eduard Klaghofer Peter Strauss 《Journal of the American Water Resources Association》2008,44(5):1108-1120
Abstract: Quantifying the hydrologic responses to land use/land cover change and climate variability is essential for integrated sustainable watershed management in water limited regions such as the Loess Plateau in Northwestern China where an adaptive watershed management approach is being implemented. Traditional empirical modeling approach to quantifying the accumulated hydrologic effects of watershed management is limited due to its complex nature of soil and water conservation practices (e.g., biological, structural, and agricultural measures) in the region. Therefore, the objective of this study was to evaluate the ability of the distributed hydrologic model, MIKE SHE to simulate basin runoff. Streamflow data measured from an overland flow‐dominant watershed (12 km2) in northwestern China were used for model evaluation. Model calibration and validation suggested that the model could capture the dominant runoff process of the small watershed. We found that the physically based model required calibration at appropriate scales and estimated model parameters were influenced by both temporal and spatial scales of input data. We concluded that the model was useful for understanding the rainfall‐runoff mechanisms. However, more measured data with higher temporal resolution are needed to further test the model for regional applications. 相似文献
53.
The Ganqinfen system – a process of manually cleaning animal feces by means of a shovel – is a widely used manure separating method in Chinese pig farms. Ganqinfen pig feces and chopped corn stalks were mixed at the ratio of 7:1, and composted in 1.5 m3 rotting boxes for 70 d. Evolution of CH4, N2O and NH3 during composting, and the effects of turning and covering, were studied in this research. Results showed that 20–39% and 0.5–4% of total nitrogen were lost in the form of NH3 and N2O respectively, and 0.1–0.9% of initial organic carbon was emitted as CH4. Turning enhanced air exchange in the piles, thus decreasing CH4 emission by 83–93% and shortening the maturing period. When trials were finished, all non-turned piles were separated to three layers by moisture content. This structure caused the N2O losses of non-turning treatments to be 6–12.7 times higher than that of turning treatments. Covering materials reduced air exchange at the surface of the pile, thus decreasing the O2 supply and consequently increasing CH4 production by 33–45%. Covering also reduced NH3 emission by 4–34%. For the composting of Ganqinfen pig feces, we suggest that a program of turning twice weekly without covering will result in compost that is sufficiently matured after 6 wk with the lowest resultant greenhouse gas emission. 相似文献
54.
Eduard Ariza 《Journal of Coastal Conservation》2011,15(4):445-455
In the present paper, the current beach management framework in the North-Western Mediterranean coast (Catalonia, Spain) was
revised. Beach management was analyzed using the concepts of Integrated Coastal Zone Management (ICZM). The history of beach
management in the second half of the 20 century and the new developments in the academic field and in the practical beach
management sector during the last decade were studied. The revision of legal texts and strategies in the Catalan coast allowed
synthesizing all scattered information affecting beach management. A SWOT analysis was performed. The main strengths of the
beach management framework in Catalonia are the public ownership of beaches, which allows the government to carry out a comprehensive
management and the recent data and analysis provided by the adopted National and Autonomous ICZM strategies. The weaknesses
found were related to the functioning of traditional existing institutions. New opportunities are related to the possibility
of establishing new institutions that conduct a more inclusive and proactive management. The main threat is that although
the possibility for a fundamental change in beach management organization exists, resources available are not fully exploited. 相似文献
55.
J A Libra C Sahlmann A Schuchardt J Handschag U Wiesmann R Gnirss 《Water environment research》2005,77(5):447-454
The aeration systems of two full-scale, activated-sludge basins were compared during a period of three years, under the same operating conditions, using dynamic offgas testing. Only the material of the diffuser was different (membrane versus ceramic-tube diffusers). The investigation has shown that, although the membrane diffusers have higher initial standard-oxygen-transfer efficiency (alphaSOTE) and standard-aeration efficiency (alphaSAE), these decreased over time, while the alphaSAE of the ceramic diffusers started lower, but increased slightly over the whole period. A cost comparison makes clear how important it is to evaluate the aeration system under process conditions. The operating costs were the dominant factor (approximately 10x higher than capital costs), and operating costs were approximately 20% higher for membrane versus ceramic diffusers. The poor performance of the membrane-tube diffusers under process conditions could be explained on the basis of the actual alphaAE values in the basin, not the standardized values. 相似文献
56.
57.
58.
59.
60.
Fetal evaluation of the modified-myocardial performance index in pregnancies complicated by diabetes