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111.
塔里木河中游段治理中的牧区水利建设   总被引:1,自引:0,他引:1  
塔里木河中下游地区生态环境急剧恶化,最主要的原因是中游段河水近一半21×108m3被人为的散失,造成下游河水所剩无几,致使尾闾台特玛湖干涸。解决的根本办法是将中下游段两岸的农牧民迁出,实现人为耗水为零。近期切实可行的办法是积极开展牧区水利建设,改变牧业生产方式,集中高效利用塔河水资源,发展人工草地,改良天然草场,实现牧业生产生态环境的协调发展,人与自然和谐相处。  相似文献   
112.
长庆油房庄油田水经过处理后仍具有较高的矿化度、较多的悬浮物及残留油,同时其SRB严重超标。现场处理水质不稳定,在进行回注时与地层的配伍性较差。针对这些情况,研究了一种新型的水处理工艺技术。对成垢离子调整剂、水质净化剂和成垢离子钝化剂进行了筛选,并对含油污水的成垢离子含量及比例进行了调整。运用这种技术,使油房庄油田水经处理后达到回注水的标准,且提高了与地层的配伍性。同时提出了新型水处理技术的工艺流程。  相似文献   
113.
按枣庄矿区十年发展规划,未来十年矿区煤炭产量将达到1800万t,矿区自营铁路煤炭外运将突破1000万t.为实现枣矿集团大集团战略目标,本文从矿区自营铁路运营现状及影响安全运输能力提高的瓶颈进行调研分析,并以此为依据提出提高矿区铁路安全运输能力的对策.  相似文献   
114.
城市公共安全规划与灾害应急管理的集成研究   总被引:13,自引:0,他引:13  
随着城市公共安全理论研究与应用的不断深入,对于安全规划与灾害应急管理的孤立研究已渐露弊端.探讨了研究城市公共安全规划与灾害应急管理的融合模式,剖析了城市公共安全规划的空间范围与应变管理空间需求之间的关系,提出了以整合观和可持续发展观构建城市公共安全规划,以空间观构建城市应急管理机制的设想.在此基础上,根据有效服务范围和资源量,提出了城市各类防救灾设施的规划标准与建构模式,以建立城市救灾单元区域.  相似文献   
115.
阐述了旅游区域联动发展战略的内涵、类型、原则及意义,分析了安徽省"两山一湖"地区实施旅游区域联动战略的必要性、可能性和发展现状,提出了若干对策.  相似文献   
116.
芜湖市2003年生态足迹研究   总被引:4,自引:0,他引:4  
生态足迹是近年来较为流行的定量测定人类对自然利用程度的新方法.利用生态足迹计算方法对芜湖市2003年的生态足迹进行了实证计算与分析,计算结果显示芜湖市2003年人均生态赤字为1.65hm2,表明其发展处于不可持续状态.针对目前的状况提出了芜湖市可持续发展的对策和建议.  相似文献   
117.
采用生态系统健康理论分析开发区生态环境问题具有较强的理论意义和现实意义。着重构建了开发区生态系统健康评价的指标体系和模糊评价模型,提出评价标准。并对苏州高新区生态系统健康进行评价。进而指出制约因子并提出相应的诊断方案,为其优化生态系统结构和完善系统功能提供科学依据。  相似文献   
118.
The causes of species rarity are of critical concern because of the high extinction risk associated with rarity. Studies examining individual rare species have limited generality, whereas trait‐based approaches offer a means to identify functional causes of rarity that can be applied to communities with disparate species pools. Differences in functional traits between rare and common species may be indicative of the functional causes of species rarity and may therefore be useful in crafting species conservation strategies. However, there is a conspicuous lack of studies comparing the functional traits of rare species and co‐occurring common species. We measured 18 important functional traits for 19 rare and 134 common understory plant species from North Carolina's Sandhills region and compared their trait distributions to determine whether there are significant functional differences that may explain species rarity. Flowering, fire, and tissue‐chemistry traits differed significantly between rare and common, co‐occurring species. Differences in specific traits suggest that fire suppression has driven rarity in this system and that changes to the timing and severity of prescribed fire may improve conservation success. Our method provides a useful tool to prioritize conservation efforts in other systems based on the likelihood that rare species are functionally capable of persisting.  相似文献   
119.
The designation of no‐take marine reserves involves social and economic concerns due to the resulting displacement of fishing effort, when fishing rights are removed from those who traditionally fished within an area. Displacement can influence the functioning of the fishery and success of the reserve, yet levels of displacement are seldom quantified after reserve implementation and very rarely before that. We devised a simple analytical framework based on set theory to facilitate reserve placement. Implementation of the framework requires maps of fishing grounds, fishing effort, or catch per unit effort for at least 2 years. The framework quantifies the level of conflict that a reserve designation might cause in the fishing sector due to displacement and the opportunities to offset the conflict through fisher spatial mobility (i.e., ability of fishers to fish elsewhere). We also considered how the outputs of the framework can be used to identify targeted management interventions for each fishery. We applied the method in Honduras, where the largest marine protected area in Central America is being placed, for which spatial data on fishing effort were available for 6 fisheries over 3 years. The proposed closure had a greater negative impact on the shrimp and lobster scuba fisheries, which concentrated respectively 28% and 18% of their effort inside the reserve. These fisheries could not accommodate the displacement within existing fishing grounds. Both would be forced to stretch into new fishing grounds, which are available but are of unknown quality. These stakeholders will likely require compensation to offset costly exploratory fishing or to travel to fishing grounds farther away from port.  相似文献   
120.
Mitigation and offset programs designed to compensate for ecosystem function losses due to development must balance losses from affected ecosystems with gains in restored ecosystems. Aggregation rules applied to ecosystem functions to assess site equivalence are based on implicit assumptions about the substitutability of functions among sites and can profoundly influence the distribution of restored ecosystem functions on the landscape. We investigated the consequences of rules applied to the aggregation of ecosystem functions for wetland offsets in the Beaverhill watershed in Alberta, Canada. We considered the fate of 3 ecosystem functions: hydrology, water purification, and biodiversity. We set up an affect‐and‐offset algorithm to simulate the effect of aggregation rules on ecosystem function for wetland offsets. Cobenefits and trade‐offs among functions and the constraints posed by the quantity and quality of restorable sites resulted in a redistribution of functions between affected and offset wetlands. Hydrology and water purification functions were positively correlated with one another and negatively correlated with biodiversity function. Weighted‐average rules did not replace functions in proportion to their weights. Rules prioritizing biodiversity function led to more monofunctional wetlands and landscapes. The minimum rule, for which the wetland score was equal to the worst performing function, promoted multifunctional wetlands and landscapes. The maximum rule, for which the wetland score was equal to the best performing function, promoted monofunctional wetlands and multifunctional landscapes. Because of implicit trade‐offs among ecosystem functions, no‐net‐loss objectives for multiple functions should be constructed within a landscape context. Based on our results, we suggest criteria for the design of aggregation rules for no net loss of ecosystem functions within a landscape context include the concepts of substitutability, cobenefits and trade‐offs, landscape constraints, heterogeneity, and the precautionary principle.  相似文献   
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