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821.
Salpie Djoundourian 《Environment, Development and Sustainability》2009,11(2):427-438
The paper reviews and assesses the evolution of the environmental movement in both the public and the private sector in Lebanon.
It studies the public sector involvement in the environmental movement by reviewing the commitments made by the government
to the local, regional and international communities. The paper presents a summary of all the decisions, decrees, and laws
pertaining to environmental protection that the Lebanese government has instituted over time, as well as all the conventions
and agreements that the country has ratified and/or signed. Compared to the Arab world in the Middle East and North Africa,
Lebanon is relatively more active and integrated in the world community. Using the total number of established environmental
organizations and the level of reported activities aimed at spreading environmental awareness and educating people as indicators
of private sector involvement in the environmental movement, the paper concludes that the post war era is characterized by
a significant increase in the number of established organizations. It also concludes that there is a co-movement between economic
and environmental variables.
Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue. 相似文献
822.
The Influence of the Pacific Decadal Oscillation on Annual Floods in the Rivers of Western Canada
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Sunil Gurrapu Jeannine‐Marie St‐Jacques David J. Sauchyn Kyle R. Hodder 《Journal of the American Water Resources Association》2016,52(5):1031-1045
We analyzed annual peak flow series from 127 naturally flowing or naturalized streamflow gauges across western Canada to examine the impact of the Pacific Decadal Oscillation (PDO) on annual flood risk, which has been previously unexamined in detail. Using Spearman's rank correlation ρ and permutation tests on quantile‐quantile plots, we show that higher magnitude floods are more likely during the negative phase of the PDO than during the positive phase (shown at 38% of the stations by Spearman's rank correlations and at 51% of the stations according to the permutation tests). Flood frequency analysis (FFA) stratified according to PDO phase suggests that higher magnitude floods may also occur more frequently during the negative PDO phase than during the positive phase. Our results hold throughout much of this region, with the upper Fraser River Basin, the Columbia River Basin, and the North Saskatchewan River Basin particularly subject to this effect. Our results add to other researchers' work questioning the wholesale validity of the key assumption in FFA that the annual peak flow series at a site is independently and identically distributed. Hence, knowledge of large‐scale climate state should be considered prior to the design and construction of infrastructure. 相似文献
823.
高精度区域气候模式对淮河流域降水的模拟评估 总被引:1,自引:0,他引:1
利用CCLM(COSMO model in Climate Mode)高精度区域气候模式输出的淮河流域逐日降水数据,计算了年降水量、降水强度、大雨日数和强降水量4个降水指数,首先通过与1961~2010年流域内气象站点的降水观测数据进行对比,检验CCLM模式对淮河流域降水的模拟能力。结果表明,CCLM模式能够很好的模拟淮河流域降水的年际变化和空间分布特征,在4个降水指数中,对年降水量的模拟效果最佳。CCLM模式在SRES-A1B(中排放)情景下的降水预估数据显示,2011~2050年淮河流域降水整体将呈增加趋势,增幅在70 mm之内,降水量年际变率较大,波动范围达-40%~60%,很有可能造成未来旱涝灾害的频繁发生。空间分布上,流域南部和中部在未来40年内降水呈增加趋势,增幅不超过67%,其他区域则呈减少趋势,减幅不超过106% 相似文献
824.
长江流域重要生态环境敏感区分布现状 总被引:2,自引:0,他引:2
采用叠图法、数学统计等方法,对长江流域自然保护区、风景名胜区、地质公园、森林公园、世界文化和自然遗产地的数量、面积、分布等基本情况进行了识别、整理、统计分析与制图,从长江流域内分布的具有全球保护意义、国家保护意义、流域保护意义、区域保护意义的角度,辨识长江流域存在的不同类型的生态环境敏感区,同时分析了水能资源丰富的长江上游区重要生态环境敏感区分布状况。长江流域已形成了以自然保护区、风景名胜区、地质公园、森林公园、世界文化和自然遗产地等多类型、多层次的自然与文化资源保护体系,对中国自然与文化资源保护具有重要作用 相似文献
825.
Rubens S. Gondim Marco A.H. de Castro Aline de H.N. Maia Sílvio R.M. Evangelista Sérgio C. de F. Fuck 《Journal of the American Water Resources Association》2012,48(2):355-365
Gondim, Rubens S., Marco A.H. de Castro, Aline de H.N. Maia, Sílvio R.M. Evangelista, and Sérgio C. de F. Fuck, Jr., 2012. Climate Change Impacts on Irrigation Water Needs in the Jaguaribe River Basin. Journal of the American Water Resources Association (JAWRA) 48(2): 355‐365. DOI: 10.1111/j.1752‐1688.2011.00620.x Abstract: Climate change is conceptually referred to as a modification to the average of climate variables and their natural variability, due to both natural and anthropogenic driving forces, such as greenhouse gas emissions. Climate change potentially impacts rainfall, temperature, and air humidity, which have relationship with plant evapotranspiration and consequently to irrigation water needs (IWN). The purpose of this research is to assess climate change impacts on irrigation water demand, based on climatic impacts stemming from future greenhouse gas emission scenarios. The study area includes eight municipalities in the Jaguaribe River Basin, located in the Ceará State of semiarid northeast Brazil. The FAO Penman‐Monteith method is used for the calculation of a reference evapotranspiration with limited climatic data. IWN projections are calculated using bias‐corrected climate projections for monthly rainfall and surface temperature derived from the United Kingdom’s Hadley Centre Regional Climate Model simulations. The increase in the average IWN is projected to be 7.9 and 9.1% over the period 2025‐2055 for the A2 and B2 scenarios, respectively with respect to 1961‐1990 baseline. 相似文献
826.
A three-dimensional/high-resolution transport model for persistent organic pollutants (POPs) has been developed for the East China Sea (ECS). The POPs model has four compartments (gaseous, dissolved, phytoplankton-bound, and detritus-bound phases) and includes processes for diffusive air-water exchange, phytoplankton uptake/depuration to POPs, decomposition of dissolved phase, vertical sinking of phytoplankton, detritus production by phytoplankton mortality, and vertical sinking and decomposition of detritus. The POPs model is coupled with an ocean circulation model that can reproduce the seasonal variation in physical variables to represent the advection and diffusion of POPs. We applied the POPs model to the polychlorinated biphenyl congener 153 (PCB 153) from the atmosphere and examined the behavior of PCB 153 in the ocean. The model showed a remarkable seasonal variability of PCB 153. Concentrations in the dissolved and particulate phases are high in winter (January-March) and low in summer (July-September). In coastal regions, where chlorophyll a concentration is high, horizontal and vertical distributions in the dissolved and particulate PCB 153 concentrations are strongly affected by phytoplankton uptake. The sensitivity experiments on the dynamics of PCB 153 suggested that a change of Henry’s law constant associated with water temperature is the major factor controlling the seasonal variability of PCB 153. The model-based yearly mass balance of PCB 153 in the ECS indicated that most of the atmospheric input (35.5 kg year−1) is removed by the horizontal advection outside the ECS (19.0 kg year−1) and accumulates to the sea bottom by vertical sinking (15.7 kg year−1). For comparison with PCB 153, we also conducted simulations for PCB 52, 101, and 180. The seasonal variations are similar to that of PCB 153. The mass balance of PCB 52 that has short half-life time and less hydrophobic property shows the different results compared with PCB 101, 153, and 180. 相似文献
827.
Heavy Metal Monitoring Using Bivalved Shellfish from Zhejiang Coastal Waters, East China Sea 总被引:2,自引:0,他引:2
The interest of culturing bivalved shellfish (including mussels, clams, oysters etc.), has increased in recent years, but
the consumption has been hampered both by high levels of heavy metals and toxic algae. The levels of heavy metals (Hg, Cd,
Pb, Zn, Cu and As) were determined in soft tissues of different shellfish from Zhejiang coastal waters, East China Sea. The
average concentrations of the heavy metals analyzed exhibited the following decreasing order: Zn > Cu > As > Cd > Pb > Hg.
Comparison of heavy metals concentrations among species indicated that Bivalves clearly have significant potential as useful
bioindicators; however, the results indicated that no one species is universally suitable, as is true of any organism used
in these studies. The distribution of the metals was also investigated along the Zhejiang coast, which the results showed
the mean concentration of Hg and Cd detected did not vary greatly and presented a similar spatial pattern at different sampling
stations, the concentrations of Zn and Pb were highly variable at different sampling sites. The amounts of heavy metals in
soft tissue of shellfish were also compared with those from the related species from other seas in China and world marine
waters. The results suggested that the coastal area might be considered relatively unpolluted with heavy metals and the concentrations
of metals in shellfish also below the seafood safety limits for human consumption. 相似文献
828.
Bytnerowicz A Arbaugh M Schilling S Fraczek W Alexander D 《Environmental pollution (Barking, Essex : 1987)》2008,155(3):398-408
In the San Bernardino Mountains of southern California, ozone (O(3)) concentrations have been elevated since the 1950s with peaks reaching 600ppb and summer seasonal averages >100ppb in the 1970s. During that period increased mortality of ponderosa and Jeffrey pines occurred. Between the late 1970s and late1990s, O(3) concentrations decreased with peaks approximately 180ppb and approximately 60ppb seasonal averages. However, since the late 1990s concentrations have not changed. Monitoring during summers of 2002-2006 showed that O(3) concentrations (2-week averages) for individual years were much higher in western sites (58-69ppb) than eastern sites (44-50ppb). Potential O(3) phytotoxicity measured as various exposure indices was very high, reaching SUM00 - 173.5ppmh, SUM60 - 112.7ppmh, W126 - 98.3ppmh, and AOT40 - 75ppmh, representing the highest values reported for mountain areas in North America and Europe. 相似文献
829.
Meiyun Lin Taikan Oki Magnus Bengtsson Shinjiro Kanae Tracey Holloway David G. Streets 《Atmospheric environment (Oxford, England : 1994)》2008,42(24):5956-5967
Region-to-grid source–receptor (S/R) relationships are established for sulfur and reactive nitrogen deposition in East Asia, using the Eulerian-type Community Multiscale Air Quality (CMAQ) model with emission and meteorology data for 2001. We proposed a source region attribution methodology by analyzing the non-linear responses of the CMAQ model to emission changes. Sensitivity simulations were conducted where emissions of SO2, NOx, and primary particles from a source region were reduced by 25%. The difference between the base and sensitivity simulations was multiplied by a factor of four, and then defined as the contribution from that source region. The transboundary influence exhibits strong seasonal variation and generally peaks during the dry seasons. Long-range transport from eastern China contributes a significant percentage (>20%) of anthropogenic reactive nitrogen as well as sulfur deposition in East Asia. At the same time, northwestern China receives approximately 35% of its sulfur load and 45% of its nitrogen load from foreign emissions. Sulfur emissions from Miyakejima and other volcanoes contribute approximately 50% of the sulfur load in Japan in 2001. Sulfur inflows from regions outside the study domain, which is attributed by using boundary conditions derived from the MOZART global atmospheric chemistry model, are pronounced (10–40%) over most parts of Asia. Compared with previous studies using simple Lagrangian models, our results indicate higher influence from long-range transport. The estimated S/R relationships are believed to be more realistic since they include global influence as well as internal interactions among different parts of China. 相似文献
830.
浅谈三江源区隆务河流域水资源现状 总被引:2,自引:1,他引:1
本文对三江源自然保护区的重要河流——隆务河流域的水环境污染源、污染物及其排放状况进行了现场全方位调查,选取pH、Cr6+、DO、COD等为监测项目,调查结果表明该地区水资源已经达不到国家地表水环境质量标准(GB 3838—2002)要求。本文还分析其污染源沿河流呈零星分布的特点,阐述了污染物对环境造成的危害,为三江源的水环境可持续发展提供保障。 相似文献