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331.
为实现水资源的循环利用与国民经济的可持续发展,必须对工业废水进行处理。在过去的几十年中,工业废水的任意排放给水资源环境和人民的身体健康带来了巨大的危害,为了杜绝这种现象的再次出现,本文对工业废水的处理方法做了如下的探讨。  相似文献   
332.
京津冀地区面向人居环境之水安全格局初探   总被引:1,自引:0,他引:1  
采用文献法对近年京津冀水资源、水环境、水污染、水灾害、水管理等水安全情势进行相关数据分析,从总体上显示出水危机问题和京津冀地区快速城市化发展的关联性.结果表明:1)京津冀城市群必须向节水型社会模式转型;2)建立区域及城市间的协调机制,才能有效克服流域与区域等级的水问题;3)实现京津冀地区水安全格局的治理行动计划网络,提出保护恢复体系、净化循环体系、限制节约体系、调度再造体系、蓄滞防洪减灾体系五大体系.  相似文献   
333.
为提升紧急情况下复杂建筑空间中应急疏散引导的疏散效率,采用仿真模拟方法,提出1套可适用于复杂建筑空间人员应急疏散的无人机引导模型,该模型通过改进传统算法和构建新方法,实现无人机空间遍历移动规则寻优、无人机引导路径寻优以及基于“障碍物空间场域”建筑空间区域划分。研究结果表明:相较于没有无人机引导,采用单无人机和多无人机协同引导疏散,可大幅缩短整体疏散时间,有效减少疏散路径当量长度,提高疏散效率并保证路径安全,为无人机在应急救援和疏散的应用提供新思路。  相似文献   
334.
Abstract:  Selecting reserve areas based on percentages, such as 10% or 12% of a bioregion, is common in conservation planning despite widespread admission that such percentages are arbitrary and likely to be inadequate for the conservation of all biodiversity. Reserve systems based on these relatively low percentage targets are likely to require expansion in the future, resulting in the assembly of reserve systems over many years (incremental reserve design). How then will incremental reserve design, such as increasing percentage targets over time, affect the long-term efficiency of marine reserve systems? We used South Australia as a case study to investigate how changing percentage targets affects the contribution of individual planning units to efficient reserve design. Selection frequency counts provided a measure of a planning unit's conservation value. For the majority of planning units, changing targets led to a change in their conservation value indicating, for example, that planning units identified as high-value sites at a low-percentage conservation target may be of lesser importance when targets are increased. Despite the variability in the value of individual planning units at different targets, there was no loss in efficiency from incremental design of reserve systems based on systematic methods compared with purpose-built reserve systems (i.e., the system is assembled in a single iteration). The exception was when incrementally designed systems were based on South Australia's existing marine reserve system—a system developed in an ad hoc method. The result was reserve systems that were less efficient, less compact, and larger in size. This suggests that systematic approaches have an important role for efficient reserve design when there is uncertainty about the target level of reservation .  相似文献   
335.
Abstract:  The Iberian Peninsula harbors about 50% of European plant and terrestrial vertebrate species and more than 30% of European endemic species. Despite the global recognition of its importance, the selection of protected areas has been ad hoc and the effectiveness of such choices has rarely been assessed. We compiled the most comprehensive distributional data set of Iberian terrestrial plant and vertebrate species available to date and used it to assess the degree of species representation within existing protected areas. Existing protected areas in Spain and Portugal reasonably represented the plant and animal species we considered (73–98%). Nevertheless, species of some groups (amphibians, reptiles, birds, and gymnosperms) did not accumulate in protected areas at a rate higher than expected by chance ( p > 0.05). We determined that to conserve all vertebrate and plant species in the Iberian Peninsula, at least 36 additional areas are needed. Selection of additional areas for conservation would be facilitated if such areas coincided with sites of community importance (SCI) designated under the European Commission Habitats Directive. Additional areas required for full representation of the selected plant and animal species all coincide with SCI in Spain. Nevertheless, the degree of coincidence varies between 0.3% and 74.6%, and there is a possibility that important areas for conservation occur outside the SCI. Our results support the view that current SCI can be used for prioritization of areas for conservation, but a systematic reevaluation of conservation priorities in Spain and Portugal would be necessary to ensure that effective conservation of one of European's most important biodiversity regions is achieved.  相似文献   
336.
Abstract:  Uncertainty in the implementation and outcomes of conservation actions that is not accounted for leaves conservation plans vulnerable to potential changes in future conditions. We used a decision-theoretic approach to investigate the effects of two types of investment uncertainty on the optimal allocation of global conservation resources for land acquisition in the Mediterranean Basin. We considered uncertainty about (1) whether investment will continue and (2) whether the acquired biodiversity assets are secure, which we termed transaction uncertainty and performance uncertainty, respectively. We also developed and tested the robustness of different rules of thumb for guiding the allocation of conservation resources when these sources of uncertainty exist. In the presence of uncertainty in future investment ability (transaction uncertainty), the optimal strategy was opportunistic, meaning the investment priority should be to act where uncertainty is highest while investment remains possible. When there was a probability that investments would fail (performance uncertainty), the optimal solution became a complex trade-off between the immediate biodiversity benefits of acting in a region and the perceived longevity of the investment. In general, regions were prioritized for investment when they had the greatest performance certainty, even if an alternative region was highly threatened or had higher biodiversity value. The improved performance of rules of thumb when accounting for uncertainty highlights the importance of explicitly incorporating sources of investment uncertainty and evaluating potential conservation investments in the context of their likely long-term success.  相似文献   
337.
循环经济产业园规划与相关规划的协调性分析是论证循环经济产业园规划合理性的关键环节之一。以武汉市千子山循环经济产业园为例,通过对该产业园规划与产业政策和相关规划的协调性分析,论证了千子山循环经济产业园规划的合理性,为国内同类产业园规划提供参考。  相似文献   
338.
生态住宅已成为住宅建设的发展趋势和潮流,水环境是生态住宅小区的重要组成部分。文章以中信保利达美景度假区为实例,根据度假区建筑总体规划方案,结合当地自然条件和水环境现状,探讨生态住宅小区的水环境规划,全面统一规划住宅小区内各种水系统,提出小区水环境总体规划方案,充分发挥各系统的功能,使其相互衔接、协调与补充。重点对项目所在区域开发前后的水量平衡,水库的水位变化及其安全性,极端气候条件下的库区水量变化及其因应对策,高尔夫球道的用水方案以及项目开发后的水循环模型做了深入探讨,旨在为生态住宅的水环境建设提供范例。  相似文献   
339.
2008年8月,选择具有代表性的样地(受冰雪灾害较轻、受到冰雪灾害影响、受到冰雪灾害后皆伐清理样地),用野外调查和室内分析相结合的方法,对广东省天井山林场杉木人工林土壤理化性质进行分析。结果表明:(1)粤北地区杉木人工林在受到冰雪灾害后,0-60 cm的土壤容重比未受到损害的上升8.1%-16.4%,孔隙度下降8.9%-11.9%,自然含水量减少17.1%-28.6%,皆伐清理后,土壤容重比未受到损害的下降1.5%~9.5%;孔隙度上升1.2%~5.9%,自然含水量增加44.2%~68.1%。(2)受损后,土壤pH值未发生变化,浅层(0-40 cm)有机质质量分数比未损样地下降(1.3%-9.4%),深层(〉40 cm)有机质质量分数提高30.5%;各层土壤全氮、全磷、有效氮、有效磷和有效钾质量分数分别下降13.4%、30.3%、16.7%、37.6%和37.2%,全钾质量分数上升21.0%,且与未损样地的差异显著;土壤交换性钙和交换性镁大幅减少,分别为28.1%和43.4%。进行皆伐清理后,有机质质量分数比未损样地提高207.9%,土壤全氮、全钾、有效氮和有效磷质量分数升高138.7%、10.2%、161.3%和540.0%,全磷、有效钾、交换性钙和交换性镁的质量分数下降2.6%、9.0%、28.7%和24.3%,各土层变化不一致。(3)冰雪灾害的发生使杉木人工林林下土壤紧实度增加,不利于土壤呼吸、空气传导和土壤养分的累积;而经过清理后,土壤变得较为疏松,通透性增强,含水量增加,有利于土壤团粒结构的增强、土壤微生物活动和土壤养分的累积及转化。因此,冰雪灾害后对受损林地进行及时的清理对植被恢复重建尤为重要。  相似文献   
340.
王晓俊 《生态环境》2011,20(3):589-594
分析了路段与景观两个尺度上的道路生态环境影响,结合当今景观生态学、道路生态学的研究成果,系统论述了与道路交通规划建设相关的生态策略:(1)在区域尺度上,依据生态敏感度规划路网密度、保持大型自然空间的生态完整性、提倡非生态敏感地段的交通集中、增加路网的区域水平渗透性;(2)在路段规模上,自然空间的生境避让、保持重要地段的自然连续性、打破交通生态瓶颈、减少道路交通的环境影响、补偿道路建设的生态影响等。这些策略旨在为可持续道路交通提供基于生态合理性的规划原则与方法。  相似文献   
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