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61.
Jordan Wood Jonathan D. Ballou Taylor Callicrate Jeremie B. Fant M. Patrick Griffith Andrea T. Kramer Robert C. Lacy Abby Meyer Sara Sullivan Kathy Traylor-Holzer Seana K. Walsh Kayri Havens 《Conservation biology》2020,34(6):1416-1425
Maintaining a living plant collection is the most common method of ex situ conservation for plant species that cannot be seed banked (i.e., exceptional species). Viability of living collections, and their value for future conservation efforts, can be limited without coordinated efforts to track and manage individuals across institutions. Using a pedigree-focused approach, the zoological community has established an inter-institutional infrastructure to support long-term viability of captive animal populations. We assessed the ability of this coordinated metacollection infrastructure to support the conservation of 4 plant species curated in living collections at multiple botanic gardens around the world. Limitations in current practices include the inability to compile, share, and analyze plant collections data at the individual level, as well as difficulty in tracking original provenance of ex situ material. The coordinated metacollection framework used by zoos can be adopted by the botanical community to improve conservation outcomes by minimizing the loss of genetic diversity in collections. We suggest actions to improve ex situ conservation of exceptional plant species, including developing a central database to aggregate data and track unique individuals of priority threatened species among institutions and adapting a pedigree-based population management tool that incorporates life-history aspects unique to plants. If approached collaboratively across regional, national, and global scales, these actions could transform ex situ conservation of threatened plant species. 相似文献
62.
选择典型造纸厂,采用化学激活报告基因法(CALUX)测定造纸过程中废水和纸浆中的二噁英类物质,并将部分样品测定结果与高分辨气相色谱-高分辨质谱(HRGC-HRMS)法测定结果作线性回归,换算系数为0.21,表明CALUX可用于造纸行业废水中二噁英类物质的快速筛查。将CALUX用于测定造纸厂废水中二噁英类物质,结果表明用含元素氯的漂白工艺会产生大量二噁英类物质,其中漂白废水中的目标物毒性当量浓度最高,经处理后可达到国家排放标准;而用无元素氯的漂白工艺,二噁英类物质的产生量会大幅降低。 相似文献
63.
张家港河凤凰段位于张家港市凤凰镇,受上游、支流水质以及区域生活污染源等影响,河道出入境断面水质达标率较低,主要超标因子为氨氮和总磷。本文通过水质现状分析和现场调研,总结了水质难达标的主要原因,提出了针对性较强的水质提升整治方案,对改善张家港河水环境具有非常重要的意义。 相似文献
64.
在我国经济发展势头如此迅猛的背景下,城市污染问题日益严重。城市黑臭水体对城市生态环境造成严重影响,如果不能及时进行治理,则会对原有水生态循环系统造成破坏,影响城市居民正常生活。本文首先对城市黑臭水体产生原因进行分析,然后提出有效的治理对策。 相似文献
65.
工业水的处理一直以来都是环境工程当中十分重要的一个环节,而要做好这一环节就需要针对其中存在的问题进行科学合理的优化控制过程,本文从这一点出发,提出工业水处理过程中相关的工作内容。 相似文献
66.
本文首先介绍了我国当前的河湖水环境现状,分析了我国水资源存在的一系列问题,主要问题包括水体污染和富营养化;河湖面积严重萎缩,河湖水的功能逐渐退化;难以降解的有机污染物污染量加大。有针对性地提出了改善我国河湖水环境的管理以及治理模式,进一步落实了保护河湖水环境工作,加强水资源周围生态环境的文明建设,实现河湖水环境的可持续发展。 相似文献
67.
In this work we present a method for risk-informed decision-making in the physical asset management context whereby risk evaluation and cost-benefit analysis are considered in a common framework. The methodology uses quantitative risk measures to prioritize projects based on a combination of risk tolerance criteria, cost-benefit analysis and uncertainty reduction metrics. There is a need in the risk and asset management literature for a unified framework through which quantitative risk can be evaluated against tolerability criteria and trade-off decisions can be made between risk treatment options. The methodology uses quantitative risk measures for loss of life, loss of production and loss of property. A risk matrix is used to classify risk as intolerable, As Low As Reasonably Practicable (ALARP) or broadly tolerable. Risks in the intolerable and ALARP region require risk treatment, and risk treatment options are generated. Risk reduction benefit of the treatment options is quantified, and cost-benefit analysis is performed using discounted cashflow analysis. The Analytic Hierarchy Process is used to derive weights for prioritization criteria based on decision-maker preferences. The weights, along with prioritization criteria for risk reduction, tolerance criteria and project cost, are used to prioritize projects using the Technique for Order Preference by Similarity to Ideal Solution. The usefulness of the methodology for improved decision-making is illustrated using a numerical example. 相似文献
68.
69.
With the development of the city, the number of establishments that are proposed or under construction is increasing year by year, and if they are industries that handle flammable, explosive, toxic, harmful, and dangerous substances, the public safety will face great threats, which will bring great challenges to emergency rescue work. Therefore, providing reasonable solutions to the problem of location selection of emergency supplies repositories are necessary for improving the emergency response efficiency in chemical industrial parks. A mathematical model for location selection of emergency supplies repositories in emergency logistics management are presented considering more actual factors. The optimization objectives of the model are to minimize total transport length and cost. And then a Variable Weighted Algorithm is designed to solve the model, where an auxiliary function was constructed with different methods of building weighting factors based on the theory and method of solving multi-objective optimization problems in operational research. Simulation results show the effectiveness and feasibility of the models and algorithms presented in this paper. 相似文献
70.
Effects of land use,cover, and protection on stream and riparian ecosystem services and biodiversity
Protected areas are an important part of broader landscapes that are often used to preserve biodiversity or natural features. Some argue that protected areas may also help ensure provision of ecosystem services. However, the effect of protection on ecosystem services and whether protection affects the provision of ecosystem services is known only for a few services in a few types of landscapes. We sought to fill this gap by investigating the effect of watershed protection status and land use and land cover on biodiversity and the provision of ecosystem services. We compared the ecosystem services provided in and around streams in 4 watershed types: International Union for Conservation of Nature category II protected forests, unprotected forests, unprotected forests with recent timber harvesting, and unprotected areas with agriculture. We surveyed 28 streams distributed across these watershed types in Quebec, Canada, to quantify provisioning of clean water, carbon storage, recreation, wild foods, habitat quality, and terrestrial and aquatic biodiversity richness and abundance. The quantity and quality of ecosystem services and biodiversity were generally higher in sites with intact forest—whether protected or not—relative to those embedded in production landscapes with forestry or agriculture. Clean-water provision, carbon storage, habitat quality, and tree diversity were significantly higher in and around streams surrounded by forest. Recreation, wild foods, and aquatic biodiversity did not vary among watershed types. Although some services can be provided by both protected and unprotected areas, protection status may help secure the continued supply of services sensitive to changes in land use or land cover. Our findings provide needed information about the ecosystem service and biodiversity trade-offs and synergies that result from developing a watershed or from protecting it. 相似文献