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301.
Exxon Neftegas Limited, as operator of the Sakhalin-1 consortium, is developing oil and gas reserves on the continental shelf off northeast Sakhalin Island, Russia. DalMorNefteGeofizika (DMNG) on behalf of the Sakhalin-1 consortium conducted a 3-D seismic survey of the Odoptu license area during 17 August–9 September 2001. A portion of the primary feeding area of the endangered western gray whale (Eschrichtius robustus) is located in the vicinity of the seismic survey. This paper presents data to assess whether western gray whale bottom feeding activity, as indicated by visible mud plumes, was affected by seismic operations. The mitigation and monitoring program associated with the seismic survey included aerial surveys during 19 July–19 November 2001. These aerial surveys documented the local and regional distribution, abundance, and bottom feeding activity of western gray whales. Data on gray whale feeding activity before, during and after the seismic survey were collected, with the whales assumed to be feeding on the benthos if mud plumes were observed on the surface. The data were used to assess the influence of seismic survey and other factors (including environmental) on feeding activity of western gray whales. A stepwise multiple regression analysis failed to find a statistically significant effect (α = 0.05) of the seismic survey on frequency of occurrence of mud plumes of western gray whales used as a proxy to evaluate bottom feeding activity in Piltun feeding area. The regression indicated that transect number (a proxy for water depth, related to distance from shore) and swell height (a proxy for sea state) were the only variables that had a significant effect on frequency of whale mud plumes. It is concluded that the 2001 seismic survey had no measurable effect (α = 0.05) on bottom feeding activity of western gray whales off Sakhalin Island. M.W. Newcomer, deceased  相似文献   
302.
Exxon Neftegas Limited, operator of the Sakhalin-1 consortium, is developing oil and gas reserves on the continental shelf off northeast Sakhalin Island, Russia. DalMorNefteGeofizika (DMNG), on behalf of the Sakhalin-1 consortium, conducted a 3-D seismic survey of the Odoptu license area during 17 August–9 September 2001. A portion of the primary known feeding area of the endangered western gray whale (Eschrichtius robustus) is located adjacent to the seismic block. The data presented here were collected as part of daily monitoring to determine if there was any measurable effect of the seismic survey on the distribution and abundance of western gray whales. Mitigation and monitoring program included aerial surveys conducted between 19 July and 19 November using the methodology outlined by the Southern California High Energy Seismic Survey team (HESS). These surveys provided documentation of the distribution, abundance and bottom feeding activity of western gray whales in relation to seismic survey sounds. From an operations perspective, the aerial surveys provided near real-time data on the location of whales in and outside the feeding area, and documented whether whales were displaced out of an area normally used as feeding habitat. The objectives of this study were to assess (a) temporal changes in the distribution and abundance of gray whales in relation to seismic survey, and (b) the influence of seismic survey, environmental factors, and other variables on the distribution and abundance of gray whales within their preferred feeding area adjacent to Piltun Bay. Multiple regression analysis revealed a limited redistribution of gray whales southward within the Piltun feeding area when the seismic survey was fully operational. A total of five environmental and other variables unrelated to seismic survey (date and proxies of depth, sea state and visibility) and one seismic survey-related variable (seg3d, i.e., received sound energy accumulated over 3 days) had statistically significant effects on the distribution and abundance of gray whales. The distribution of two to four gray whales observed on the surface (i.e., about five to ten whales in total) has likely been affected by the seismic survey. However, the total number of gray whales observed within the Piltun feeding area remained stable during the seismic survey. M. W. Newcomer, Deceased.  相似文献   
303.
对黑潴河下游表层沉积物中16种多环芳烃(PAHs)的污染现状进行了调查研究。结果表明,表层沉积物中PAHs总量变化范围为41.2~129.3ng/g(平均值为83.7ng/g),PAHs的组成以5~6环PAHs组分为主。黑潴河下游沉积物中PAHs主要来源于周边地区化石燃料的高温燃烧。比较了基于不同方法建立的沉积物中PAHs环境基准值的差异,分析产生差异的原因,选择生态效应区间法对黑潴河沉积物中的PAHs进行了生态风险评价。黑潴河下游PAHs生态风险较小,属PAHs低生态风险河道。  相似文献   
304.
环境空气质量分析的实践与探讨   总被引:2,自引:1,他引:1  
以丹东市环境空气质量分析为例对当前采用的环境空气质量分析方法的优缺点进行了评述,指出采用全市多点位平均值分析环境空气质量具有一定缺欠,它们的均值会平滑掉重污染点的监测峰值,反映不出城市应有的污染来;应把对重污染点的监测值的分析作为重点,辅以全市多点位的平均值,分析环境空气污染特征、变化规律,进而查找其污染原因,提出可行的减少或消除环境空气污染的措施和办法。  相似文献   
305.
We compared three formalisms derived from (1) medical sciences, (2) environmental, and (3) agronomic models to simulate the effects of pH and temperature on the nitrification rate in arable soils. We evaluated these formalisms by implementing them in a simple growth model by comparing modelled and measured nitrate contents of soil samples with different initial soil pH after incubation at two temperatures. We found that the formalisms derived from medical sciences were more accurate and easily adapted to the data, suggesting that such formalisms may be profitably used in agronomic or environmental models.  相似文献   
306.
环境应急监测管理体系研究   总被引:6,自引:4,他引:2  
从环境应急监测制度建设和突发性环境事件应急预案两个方面就环境应急监测管理体系问题进行了论述。在制度建设方面主要介绍了环境应急事件应注意的几个问题及解决办法,从环境主管部门、企业、人员、装备及应对的方式方法等几个方面提出了自己的想法和观点。在突发性环境事件应急预案方面主要介绍了应包含的内容、制订要求及演练过程。  相似文献   
307.
采用先进的物联网、云计算和模型仿真等技术,陈述了基于自动监测监控技术的环境安全防控系统的设计和应用。该系统利用物联网、GIS等先进技术,将重点源企业、河流断面、放射源等纳入到统一的环境监控网络中,全方位构建区域内环境安全防控大格局。根据城市环境应急现状,建立三级环境安全防控体系,实现对环境安全事故的有效预防、控制和处置。  相似文献   
308.
北方沙尘暴对杭州大气环境的影响及应对措施   总被引:1,自引:0,他引:1  
简述了我国沙尘天气的形成与分级情况。分析了我国沙尘天气的发展趋势与原因及其对杭州大气环境的影响情况。指出我国沙尘天气的发展有越演越烈的趋势 ,对杭州大气环境的影响时间延长 ,频次增加 ,危害程度加重 ,范围扩大。对防治沙尘天气污染大气环境提出了应对措施。  相似文献   
309.
310.
A stochastic linear fractional programming (SLFP) approach is developed for supporting sustainable municipal solid waste management under uncertainty. The SLFP method can solve ratio optimization problems associated with random information, where chance-constrained programming is integrated into a linear fractional programming framework. It has advantages in: (1) comparing objectives of two aspects, (2) reflecting system efficiency, (3) dealing with uncertainty expressed as probability distributions, and (4) providing optimal-ratio solutions under different system-reliability conditions. The method is applied to a case study of waste flow allocation within a municipal solid waste (MSW) management system. The obtained solutions are useful for identifying sustainable MSW management schemes with maximized system efficiency under various constraint-violation risks. The results indicate that SLFP can support in-depth analysis of the interrelationships among system efficiency, system cost and system-failure risk.  相似文献   
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