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51.
旅游产品的开发水平是西部旅游业发展的制约因素.在西部国内旅游营销中,要把东部客源市场作为远程旅游目标市场,远程旅游产品的开发要以市场为导向.在分析东部客源市场特点的基础上,提出了西部国内旅游远程市场旅游产品的开发策略:①体现西部特色,与东部旅游产品形成互补;②以资源保护为前提,开发生态型旅游产品;③整合西部旅游资源,开发跨区域旅游精品;④协调好各旅游要素的功能,形成不同等级的旅游服务系统;⑤针对东部地区客源市场特点设计旅游产品;⑥重视老年旅游和青少年学生旅游产品的开发.  相似文献   
52.
资源所有权制度改革与西部地区经济发展   总被引:5,自引:1,他引:5  
随着资源的开采,西部许多地区不是越来越富而是越来越穷,形成了资源富有与经济落后的强烈反差,出现了“富饶的贫困”现象。在资源所有权制度改革中应充分考虑资源利益的多主体性和不同利益主体之间的利益综合平衡,尤其需要考虑到资源所在地的利益问题,确立资源地区对属地资源的收益权,增强资源地自我约束、自我积累、自我发展的能力,才能保证西部资源的开发能有效地带动当地经济的发展。  相似文献   
53.
GIS与西部生态环境建设的有机结合将是一项长期的、复杂的系统工程。在严格论证了该项目实施的可行性之后,在可持续发展理论的指导下,运用空间分析方法,提出了项目的实施方案。在该方案中,对生态环境信息数据进行了分类,详述了空间数据文件存贮结构,查询管理子系统的开发,最后得出生态环境地理信息系统的总体结构,并简述了其功能。  相似文献   
54.
鄂西水系是国家级水源保护区,也是湖北省重要的生态旅游区。为了解鄂西水生态健康状况,于2014年10月~2017年1月不同时段在宜昌国家可持续发展实验示范区卷桥河(J)、清江利川段(Q)、宜昌市水源地黄柏河(H)和丹江口入库河流天河郧西段(T)开展了底栖动物群落特征研究。研究表明:4个河段共采集到大型底栖动物5门8纲18目61科。基于底栖动物指示种耐污性及其丰度占比分析,表明J、Q和T三河流污染程度沿水流方向呈加重趋势,而H水体健康状况整体较好。运用FBI和SIGNAL底栖生物评价指数,显示四条河流健康程度沿水流方向均呈下降趋势,但H变化趋势平缓,结果表明H水体上下游均处于较健康状态,其他3条河流上游或源头水体健康状况良好,下游受到较重污染。对主要环境因子(TP、NH3-N、CODMn和TN)做主成分分析表明,轴1的解释率达到65.1%,表明轴1可以有效表征主要环境压力梯度。FBI和SIGNAL指数与轴1线性拟合度均较高,表明二者在鄂西河流水生态健康评估中可作为快速生物评价指数。  相似文献   
55.
To estimate the response of tree vegetation to recent climate warming in the Western Caucasus, the population state of several tree species at the upper limit of their distribution has been estimated in three mountain massifs in the Belaya River basin. For this purpose, the average and maximum stem diameters, vitality, and age of trees have been determined in the transitional zone between middle-mountain and high-mountain beech-fir forests (1400–1700 m a.s.l.) and in crooked birch forests growing at the upper timberline (1810–2025 m). The upper limits of Acer platanoides, A. pseudoplatanus, Ulmus glabra, and Betula litwinowii have shown a tendency to rise. The upper limit of Abies nordmanniana has remained unchanged over the past few decades, which may be explained by a decrease in moisture supply during the warm season.  相似文献   
56.
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   
57.
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   
58.
The induction of stress-70 (Hsp70) in the blue mussels Mytilus edulis from southern Baltic after exposure to cadmium, lead and copper, administrated individually and/or as a mixture, was investigated by means of standard Western blotting using a clone 3A3 monoclonal antibody. The general course of the stress-70 induction was found to be similar for all tested metals. It could be characterised by three main features: (1) The induction of stress-70 proteins was only slightly increased at low metal concentration. (2) Strong induction of stress-70 occurred at high concentration of metals. Combination of metals (Cd+Cu) was found to increase the stress-70 level more intensely than related concentrations of singularly applied metals. (3) Five weeks of long depuration had no effect on stress-70 levels. Experiments revealed different induction of stress-70 as a response to cadmium, lead and copper exposure and confirm that the applied technique might serve as a versatile tool to assess invertebrate stress reaction to environmentally relevant heavy metals.  相似文献   
59.
西部大开发面临的环境挑战及其对策   总被引:7,自引:0,他引:7  
西部大开发面临的环境挑战主要是生态脆弱性的加重和环境污染西迁速度的加快。面对挑战,需要采取的对策及措施主要有:认真开 展对生态环境的科学研究;加强与拓展环境影响评价工作;切实加强环境管理能力建设;努力加大生态保护与建设的力度;坚决遏制环境污染 的西迁;制定与实施“西部蓝天计划”;大力加强水资源的保护与有效利用等。   相似文献   
60.
我国西部地区水资源问题与对策   总被引:1,自引:0,他引:1  
我国西部地区水资源短缺、水土流失等问题严重制约了该地区的经济发展。如何合理开发利用有限的水资源,促进西部地区的可持续发展已成为当务之急。本文分析了西部地区的水资源现状,并提出旨在促进西部地区水资源可持续利用的对策。  相似文献   
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