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191.
中国西部地区,因其独特的地理位置和地形、地貌特点而形成的生态地理单元,在中国乃至于整个亚洲地区的生态系统中具有极其重要的地位,然而,西部地区是中国生态环境最脆弱的地区.西部大开发战略实施以来,西部生态环境得到了明显的改善,但依然存在水资源失调,干旱灾害严重,植被破坏、水土流失严重,荒漠化加剧,风沙灾害蔓延等生态环境问题,生态环境恶化降低了整个西部地区对人类活动的承载能力,使自然灾害强度加剧并且频度增加,造成社会经济的突出损失、增加了社会发展成本、限制了社会经济的发展速度和方向.由此,西部地区的生态环境保护与建设显得尤为重要,刻不容缓.鉴于此,本文分析了西部地区生态环境现状以及实施生态保护建设的意义,阐析了生态保护建设目前的概况,在此基础上,深入分析了西部生态保护建设存在的问题,结合西部地区的现状给出了相关建议:西部地区生态保护、建设的管理体制进行改革和完善,建立中央宏观综合管理部门统一主管的、地方政府负总责和执行的政策框架;不断加大草地生态系统的保护和建设力度;协调好农业发展与生态保护的关系,积极发展西部地区农业的替代产业,改变当前不合理的农业生产方式和土地资源的利用模式,降低农村特别是生态脆弱地区的人地压力,迅速开展生态补偿试点,完善资源开发补偿机制,将替代产业发展纳入到生态建设工程之中;建立西部生态环境监测评估体系,全面评估西部生态环境建设,为未来的生态建设规划提供科学决策依据.  相似文献   
192.
We modeled net primary productivity (NPP) at high spatial resolution using an advanced spaceborne thermal emission and reflection radiometer (ASTER) image of a Qilian Mountain study area using the boreal ecosystem productivity simulator (BEPS). Two key driving variables of the model, leaf area index (LAI) and land cover type, were derived from ASTER and moderate resolution imaging spectroradiometer (MODIS) data. Other spatially explicit inputs included daily meteorological data (radiation, precipitation, temperature, humidity), available soil water holding capacity (AWC), and forest biomass. NPP was estimated for coniferous forests and other land cover types in the study area. The result showed that NPP of coniferous forests in the study area was about 4.4 tCha(-1)y(-1). The correlation coefficient between the modeled NPP and ground measurements was 0.84, with a mean relative error of about 13.9%.  相似文献   
193.
对新形势下新疆水资源开发有关问题的探讨   总被引:2,自引:0,他引:2  
探讨我区水资源开发中存在的有关问题,对新形势下可能的发展、应对的方案及措施进行分析论证。在西部大开发中,我区要做到水资源可持续开发与利用,必须牢固树立全流域平衡的观念,做好水资源开发规划,地下水、地下水、地表水统筹分配,联合开发,尤其要大力开发还未充分利用的地下水。发展节水农业,倡导生态农业,并重视对城市(工业)污水的资源化利用。  相似文献   
194.
In the present study, forest biomass (fuelwood, leaf fodder, leaf-litter and non-timber forest products) consumption patterns have been evaluated in the villages of Govind Wildlife Sanctuary, Uttarakhand, Western Himalaya, India. The average fuelwood consumption in the selected villages was estimated at 3.14 kg/capita/day and its energy equivalent was found 52.74 MJ/capita/day. The average leaf fodder and leaf-litter consumption was estimated at 2.70 and 2.40 kg/unit/day, respectively, and the same pattern was estimated for energy equivalent. People's perception on impacts of conservation measures and resources utilization rights were also analysed. Our results emphasized the need for regular assessment of forest resources, particularly in protected areas, where access to natural resources have been denied due to legal restrictions. The study could be a pilot to strengthen the conservation measures across the protected area network by understanding the dynamics of anthropocentric activities and their subsequent impacts on forest resources.  相似文献   
195.
The data on the ecology of bilberry and cowberry in the West Siberian Plain, Kuznetsk Ala Tau, and highland Altai are presented. Ecological ranges of these plants and amplitudes of their tolerance for some environmental factors are described.  相似文献   
196.
Atmospheric elemental, reactive and particulate mercury (Hg) concentrations were measured north of downtown Reno, Nevada, USA from November 2004 to November 2007. Three-year mean and median concentrations for gaseous elemental Hg (Hg0) were 1.6 and 1.5 ng m−3 (respectively), similar to global mean Hg0 concentrations. The three-year mean reactive gaseous Hg (RGM) concentration (26 pg m−3) was higher than values reported for rural sites across the western United States. Well defined seasonal and daily patterns in Hg0 and RGM concentrations were observed, with the highest Hg0 concentrations measured in winter and early morning, and RGM concentrations being greatest in the summer and mid-afternoon. Elevated Hg0 concentrations in winter were associated with periods of cold, stagnant air; while a regularly observed early morning increase in concentration was due to local source and surface emissions. The observed afternoon increase and high summer values of RGM can be explained by in situ oxidation of gaseous Hg0 or mixing of RGM derived from the free troposphere to the surface. Because both of these processes are correlated with the same environmental conditions it is difficult to assess their overall contribution to the observed trends.  相似文献   
197.
A geophysical seismic survey was conducted in the summer of 2001 off the northeastern coast of Sakhalin Island, Russia. The area of seismic exploration was immediately adjacent to the Piltun feeding grounds of the endangered western gray whale (Eschrichtius robustus). This study investigates relative abundance, behavior, and movement patterns of gray whales in relation to occurrence and proximity to the seismic survey by employing scan sampling, focal follow, and theodolite tracking methodologies. These data were analyzed in relation to temporal, environmental, and seismic related variables to evaluate potential disturbance reactions of gray whales to the seismic survey. The relative numbers of whales and pods recorded from five shore-based stations were not significantly different during periods when seismic surveys were occurring compared to periods when no seismic surveys were occurring and to the post-seismic period. Univariate analyses indicated no significant statistical correlation between seismic survey variables and any of the eleven movement and behavior variables. Multiple regression analyses indicated that, after accounting for temporal and environmental variables, 6 of 11 movement and behavior variables (linearity, acceleration, mean direction, blows per surfacing, and surface-dive blow rate) were not significantly associated with seismic survey variables, and 5 of 11 variables (leg speed, reorientation rate, distance-from-shore, blow interval, and dive time) were significantly associated with seismic survey variables. In summary, after accounting for environmental variables, no correlation was found between seismic survey variables and the linearity of whale movements, changes in whale swimming speed between theodolite fixes, mean direction of whale movement, mean number of whale exhalations per minute at the surface, mean time at the surface, and mean number of exhalations per minute during a whales surface-to-dive cycle. In contrast, at higher received sound energy exposure levels, whales traveled faster, changed directions of movement less, were recorded further from shore, and stayed under water longer between respirations.  相似文献   
198.
In 2001–2003, >60,000 km of aerial surveys and 7,700 km of vessel surveys were conducted during June to November when critically endangered Korean–Okhotsk or western gray whales (Eschrichtius robustus) were present off the northeast coast of Sakhalin Island, Russia. Results of surveys in all years indicated gray whales occurred in predominantly two areas, (1) adjacent to Piltun Bay, and (2) offshore from Chayvo Bay, hereafter referred to as the Piltun and offshore feeding areas. In the Piltun feeding area, the majority of whales were observed in waters shallower than 20 m and were distributed from several hundred meters to ∼ 5 km from the shoreline. In the offshore feeding area during all years, the distribution of gray whales extended from southwest to northeast in waters 30–65 m in depth. During all years, the distribution and abundance of whales changed in both the Piltun and offshore feeding areas, and both north–south and inshore–offshore movements were documented within and between feeding seasons. The discovery of a significant number of whales feeding in the offshore area each year was a substantial finding of this study and raises questions regarding western gray whale abundance and population levels, feeding behavior and ecology, and individual site-fidelity. Fluctuations in the number of whales observed within the Piltun and offshore feeding areas and few sightings outside of these two areas indicate that gray whales move between the Piltun and offshore feeding areas during their summer–fall feeding season. Seasonal shifts in the distribution and abundance of gray whales between and within both the Piltun and offshore feeding areas are thought, in part, to be a response to seasonal changes in the distribution and abundance of prey. However, the mechanism driving the movements of whales along the northeast coast of Sakhalin Island is likely very complex and influenced by a multitude of factors. *Deceased  相似文献   
199.
Qiang Ye   《Resources Policy》2008,33(2):83
Western Australia is a resource-rich province. Since the 1890s, resources booms have played a key role in the development of the state's economy. In the last few years, Western Australia's resources industry has continued to enjoy exceptional conditions created by strong international demand for commodities. This paper aims to examine the likely impact of this commodity boom in the iron ore sector on the Western Australian economy, using a general equilibrium approach. The modeling results indicate that the Western Australian economy will benefit from the expansion in iron ore exports and investment in terms of rising consumption and employment, although at the industry level there will be losers as well as winners.  相似文献   
200.
中国西部地区水-能源-粮食系统耦合协调度的时空特征   总被引:1,自引:0,他引:1  
张宁  杨肖  陈彤 《中国环境科学》2022,42(9):4444-4456
在2005~2018年中国西部地区水-能源-粮食系统综合发展评价的基础上,运用耦合协调度模型和地理加权回归模型对水-能源-粮食系统耦合协调度的时空特征及其影响因素进行实证研究.结果表明:(1)中国西部水-能源-粮食系统及其各子系统的综合发展指数总体呈波动上升趋势,其中,水资源和能源子系统在2011年后长期滞后于粮食子系统,成为西部地区水-能源-粮食系统耦合协调发展的短板.(2)2005~2018年,中国西部水-能源-粮食系统耦合协调度从勉强耦合协调进入初级耦合协调阶段,且耦合协调度呈现“南高北低”的时空特征.(3)居民消费水平和人口规模对甘肃、内蒙古等西北地区的系统耦合协调度具有正向影响,对重庆、云南等西南地区具有负向影响,影响程度在地理空间上均呈现出“北正南负”的空间特征;地方财政环保投入的影响程度从北到南逐渐增大,广西、贵州、四川、陕西的系统耦合协调度受该因素的影响最大;R&D投入强度对系统耦合协调的推动作用相对较小,影响程度呈现“北高南低”的空间特征.基于上述分析结果,提出了多资源系统联合发展视角下的区域资源管理方式,减少对有限资源间的依赖性,改善人口规模及环保科技投入等因素,构建具有西部区域特色、体现资源优势、富有竞争力的水-能源-粮食系统耦合协调发展策略.  相似文献   
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