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561.
将固相微萃取与气相色谱联用,对贵阳红枫湖水样中16种美国环境保护署优控的多环芳烃进行分析。结果表明:红枫湖水中16种多环芳烃总量为0167 1~0336 4 μg/L,与国内其它水系相比,湖中存在多环芳烃轻度污染。7种(萘、荧蒽、苯并(b)荧蒽、苯并(k)荧蒽、苯并(a)芘、茚并(1,2,3-cd)芘和苯并(ghi)苝)多环芳烃的总量未超出中国城市供水行业对多环芳烃规定的限值,但作为饮用水源,红枫湖水中的苯并(a)芘含量已超出我国标准GB3838-2002中生活饮用水地表水源地的苯并(a)芘限值,并且苯并(a)蒽、〖JX-*9〗〖SX(B-25x〗〖HT7,5”〗艹〖〗〖HT6”,5”〗屈〖HT5”〗〖SX)〗〖JX*9〗、苯并(b)荧蒽、苯并(k)荧蒽、苯并(a)芘、茚并(1,2,3-cd)芘的含量也超过了美国环境保护署地表水水质标准限值。通过多环芳烃特征参数的比值,分析了红枫湖水中多环芳烃的污染来源。污染源分析表明,湖中多环芳烃的主要来源为燃烧源,包括木材、煤以及化石燃料的燃烧,同时也有一部分多环芳烃是来源石油类物质的输入. 相似文献
562.
Pollinator welfare is a recognized research and policy target, and urban greenspaces have been identified as important habitats. Yet, landscape-scale habitat fragmentation and greenspace management practices may limit a city's conservation potential. We examined how landscape configuration, composition, and local patch quality influenced insect nesting success across inner-city Cleveland, Ohio (U.S.A.), a postindustrial legacy city containing a high abundance of vacant land (over 1600 ha). Here, 40 vacant lots were assigned 1 of 5 habitat treatments (T1, vacant lot; T2, grass lawn; T3, flowering lawn; T4, grass prairie; and T5, flowering prairie), and we evaluated how seeded vegetation, greenspace size, and landscape connectivity influenced cavity-nesting bee and wasp reproduction. Native bee and wasp larvae were more abundant in landscapes that contained a large patch (i.e., >6 ha) of contiguous greenspace, in habitats with low plant biomass, and in vacant lots seeded with a native wildflower seed mix or with fine-fescue grass, suggesting that fitness was influenced by urban landscape features and habitat management. Our results can guide urban planning by demonstrating that actions that maintain large contiguous greenspace in the landscape and establish native plants would support the conservation of bees and wasps. Moreover, our study highlights that the world's estimated 350 legacy cities are promising urban conservation targets due to their high abundance of vacant greenspace that could accommodate taxa's habitat needs in urban areas. 相似文献
563.
Liz Root Erwin van der Krabben Tejo Spit 《Journal of Environmental Planning and Management》2015,58(4):701-718
Based on a case study of the Stadshaven port redevelopment in Rotterdam, this paper explores whether existing spatial planning mechanisms and processes can be used to facilitate local-level investment in climate-resilient public infrastructure and/or whether new processes and mechanisms are required to encourage investment in climate adaptation. The study reveals several key findings. First, a lack of conventional funding sources or formalised regulatory framework allowed room for experimentation with existing mechanisms and flexible strategies. Second, project planners are currently ambivalent towards introducing new mechanisms as a means to overcome implementation challenges. The case provides evidence about the role of the governance process, not simply as a means of system coordination that exists in isolation from institutional norms and values, but rather as a space for innovation, which can contribute towards reducing the financial gap associated with climate adaptation. 相似文献
564.
为了解决城市区域消防安全评价的复杂性和不确定性,本文运用可拓优度评价法,根据相关文件并结合城市区域消防的实际情况,从火灾危险程度、城市区域特征、消防实力水平和社会管理状态4个方面选取17个指标,建立了城市区域消防安全评价指标体系并划分了消防安全等级,以洛阳市西工区为例对城市区域消防安全评价的可拓优度方法进行了验证。结果表明,可拓优度方法可以准确反映出该区域消防安全水平。 相似文献
565.
Amanda Xuereb Cassidy C. D'Aloia Marco Andrello Louis Bernatchez Marie-Josée Fortin 《Conservation biology》2021,35(3):909-920
The availability of genomic data for an increasing number of species makes it possible to incorporate evolutionary processes into conservation plans. Recent studies show how genetic data can inform spatial conservation prioritization (SCP), but they focus on metrics of diversity and distinctness derived primarily from neutral genetic data sets. Identifying adaptive genetic markers can provide important information regarding the capacity for populations to adapt to environmental change. Yet, the effect of including metrics based on adaptive genomic data into SCP in comparison to more widely used neutral genetic metrics has not been explored. We used existing genomic data on a commercially exploited species, the giant California sea cucumber (Parastichopus californicus), to perform SCP for the coastal region of British Columbia (BC), Canada. Using a RAD-seq data set for 717 P. californicus individuals across 24 sampling locations, we identified putatively adaptive (i.e., candidate) single nucleotide polymorphisms (SNPs) based on genotype–environment associations with seafloor temperature. We calculated various metrics for both neutral and candidate SNPs and compared SCP outcomes with independent metrics and combinations of metrics. Priority areas varied depending on whether neutral or candidate SNPs were used and on the specific metric used. For example, targeting sites with a high frequency of warm-temperature-associated alleles to support persistence under future warming prioritized areas in the southern coastal region. In contrast, targeting sites with high expected heterozygosity at candidate loci to support persistence under future environmental uncertainty prioritized areas in the north. When combining metrics, all scenarios generated intermediate solutions, protecting sites that span latitudinal and thermal gradients. Our results demonstrate that distinguishing between neutral and adaptive markers can affect conservation solutions and emphasize the importance of defining objectives when choosing among various genomic metrics for SCP. 相似文献
566.
南岳衡山风景名胜区景观资源的调查与评价 总被引:4,自引:0,他引:4
景观资源是旅游资源的重要组成因素,本文以自然综合体的南岳衡山为考察对象,对其景观资源进行较详尽的调查,并进行定性和定量的评价,为确定南岳衡山风景名胜区性质、规划提供基础资料. 相似文献
567.
王献溥 《生态与农村环境学报》1995,(4)
当前,任何地区的生物多样性都是自然和社会因素长期综合作用所造成。生物多样性最丰富的地区不一定全部由顶极植被所覆盖,而常常是一些包括所有演替类型的地方。本文通过讨论自然环境的变化和人类生产活动对不同区域景观的影响,探讨有关生物多样性的保护问题。 相似文献
568.
网围养殖对滆湖底栖动物群落组成及物种多样性的影响 总被引:4,自引:0,他引:4
2002年4月、7月、11月和2003年1月对滆湖底栖动物群落组成、分布及多样性现状进行了研究.结果表明,滆湖现有底栖动物31种,其中软体动物14种,淡水寡毛类6种,水生昆虫7种和水蛭4种.主要优势种为梨形环棱螺和羽摇蚊.相似性分析表明,滆湖网围养鱼区和网围养蟹区底栖动物群落组成相似程度较高,而都与非养殖区差异较大,说明网围养殖对底栖动物组成存在影响;而且网围养鱼对底栖动物的影响更甚于网围养蟹的影响.多样性分析表明,滆湖底栖动物多样性呈现自北向南递增以及夏秋低、冬春高的时空变化格局.图3表2参17 相似文献
569.
太行山是我国山地植被破坏历史最长、生态环境严重恶化的山地生态系统,“七五”期间国家将绿化太行山列入重点攻关项目。从1986年开始,作者根据生态工程原理提出:环境辨识工程、种群引进选择工程、种群匹配工程、水土富集工程、时间节律工程和食物链工程为主的立体林业工程新思想,并在湘山小流域建起实施模式。经四年的工作,已取得较大进展。 相似文献
570.