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161.
Abstract: In a time of increasing urbanization, the fundamental value of conserving urban biodiversity remains controversial. How much of a fixed budget should be spent on conservation in urban versus nonurban landscapes? The answer should depend on the goals that drive our conservation actions, yet proponents of urban conservation often fail to specify the motivation for protecting urban biodiversity. This is an important shortcoming on several fronts, including a missed opportunity to make a stronger appeal to those who believe conservation biology should focus exclusively on more natural, wilder landscapes. We argue that urban areas do offer an important venue for conservation biology, but that we must become better at choosing and articulating our goals. We explored seven possible motivations for urban biodiversity conservation: preserving local biodiversity, creating stepping stones to nonurban habitat, understanding and facilitating responses to environmental change, conducting environmental education, providing ecosystem services, fulfilling ethical responsibilities, and improving human well‐being. To attain all these goals, challenges must be faced that are common to the urban environment, such as localized pollution, disruption of ecosystem structure, and limited availability of land. There are, however, also challenges specific only to particular goals, meaning that different goals will require different approaches and actions. This highlights the importance of specifying the motivations behind urban biodiversity conservation. If the goals are unknown, progress cannot be assessed. 相似文献
162.
JULIEN MARTIN PAUL L. FACKLER JAMES D. NICHOLS MICHAEL C. RUNGE CAROL L. McINTYRE BRUCE L. LUBOW MAGGIE C. McCLUSKIE JOEL A. SCHMUTZ 《Conservation biology》2011,25(2):316-323
Abstract: Unintended effects of recreational activities in protected areas are of growing concern. We used an adaptive‐management framework to develop guidelines for optimally managing hiking activities to maintain desired levels of territory occupancy and reproductive success of Golden Eagles (Aquila chrysaetos) in Denali National Park (Alaska, U.S.A.). The management decision was to restrict human access (hikers) to particular nesting territories to reduce disturbance. The management objective was to minimize restrictions on hikers while maintaining reproductive performance of eagles above some specified level. We based our decision analysis on predictive models of site occupancy of eagles developed using a combination of expert opinion and data collected from 93 eagle territories over 20 years. The best predictive model showed that restricting human access to eagle territories had little effect on occupancy dynamics. However, when considering important sources of uncertainty in the models, including environmental stochasticity, imperfect detection of hares on which eagles prey, and model uncertainty, restricting access of territories to hikers improved eagle reproduction substantially. An adaptive management framework such as ours may help reduce uncertainty of the effects of hiking activities on Golden Eagles. 相似文献
163.
O. Milošević-Djordjević D. Grujićić S. Arsenijević D. Marinković 《Russian Journal of Ecology》2004,35(6):426-430
Kragujevac, as an important industrial and economic center of the region, is now placed on the top of the list of environmentally endangered cities in our country. The aim of this biomonitoring study was to evaluate cytogenetic damage in a sample of newborns from Kragujevac after contamination of the environment entailed by the intensive bombing of the industrial zone of this city in the spring of 1999. The frequency of micronuclei (MN) in peripheral blood lymphocytes in a total of 61 phenotypically healthy newborns was analyzed before and after the NATO bombing. Analysis of micronuclei has been performed using the cytokinesis-block technique (CB MN test). Average MN frequency in lymphocytes of newborns before the bombing (N = 25) was 5.77 ± 0.85/1000 analyzed cells. After the bombing (N = 36), the average frequency of MN increased by a factor of 1.4 (8.11 ± 0.85), compared to the control frequency before the bombing. Statistical difference (p < 0.05) was established by Student's t-test. Our data suggest that such changes in genetic material were a direct consequence of contamination of the living environment. 相似文献
164.
Partha Dasgupta 《Sustainability Science》2007,2(1):5-11
In this lecture, I demonstrate how very different macroeconomic history begins to look if Nature is included as a capital
asset in production activities. The tentative conclusions I draw from the evidence are: (1) high population growth in the
world’s poorest regions (South Asia and sub-Saharan Africa) has been an obstacle to the achievement of sustainable economic
development there; relatedly, (2) when population growth is taken into account, the accumulation of manufactured capital,
knowledge, and human capital (health and education) has not compensated for the degradation of natural capital in South Asia
and sub-Saharan Africa and, in all probability, even in the UK and the US; (3) China is possibly an exception to (1) and (2).
This article is based on the Keynote Lecture delivered at the international symposium on “Sustainability in an Unequal World”,
held in Tokyo on November 24, 2006. The exposition relies on my book, Economics: A Very Short Introduction, Oxford University Press, Oxford, 2007.
The author is the Frank Ramsey Professor of Economics at the University of Cambridge and a Fellow of St. John’s College,
Cambridge. 相似文献
165.
Prenatal diagnosis of 5p deletion syndrome, or cri du chat, following an abnormally low measurement of a screening of serum human chorionic gonadotrophin (hCG), is reported. Karyotyping following amniocentesis revealed a terminal deletion in the short arm of one chromosome 5. The pregnancy was electively terminated. 5p deletion syndrome has been described with abnormally high hCG levels and normal hCG levels. This is the first report of its association with abnormally low levels. The association between chromosomal abnormalities and hCG is discussed. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
166.
在电子废弃物管理中生产者责任延伸制度探讨 总被引:3,自引:0,他引:3
随着2003年我国家电、通讯和电脑等电子产品的报废高峰期和宽带电讯业发展的黄金时代的到来,电子废弃物的污染问题日益引起人们的关注。我国传统废弃物的处理和管理制度的不完善。已使我国沿海地区的电子垃圾泛滥成灾,甚至威胁到内陆地区。而且电子废弃物中大量的有用资源没有得到有效回收。也不符合政府最近提倡的全民节约原则。因此,国家制定了有关电子废弃物的生产者责任延伸(EPR)制的具体法律法规。本文从环境经济学角度。结合其它国家和地区的生产者责任延伸制的颁布和运行情况。对我国电子废弃物的管理中施行生产责任延伸制进行初步探讨。 相似文献
167.
168.
通过对农户开展的问卷调查分析了锡林郭勒盟草原生态补偿绩效,结果表明生态补偿绩效不容乐观,农户感受到的生态环境状况仅有小幅度的改善,消除经济激励之后农户表现出较低的参与积极性.基于结构方程模型,以农户自我发展能力和生态保护能力为中介,构建社会资本对生态补偿绩效的影响机制模型.结果表明社会资本对经济效应表现出显著负影响;对生态效应表现出显著正影响.社会网络、普遍信任、机构信任、互助倾向和惩罚程度对于经济效应影响系数分别为-0.05、-0.05、-0.01、-0.06和-0.03;对于社会效应影响系数分别为0.11、0.10、0.03、0.12和0.06;对于生态效应影响系数分别为0.36、0.33、0.09、0.38和0.19.在社会资本5项维度中互助倾向反映度最高,机构信任最低,因子载荷分别为0.77和0.19.农户自我发展能力和生态保护能力在社会资本对生态补偿绩效影响中表现出显著中介作用. 相似文献
169.
基于人地耦合系统的国土空间重塑 总被引:3,自引:0,他引:3
地理系统主要研究地球表层人与环境相互作用的机理,强调人地关系、自然和人文要素的综合,即人地耦合系统。地理系统在国土空间中的应用主要由地理决策、地理模拟、地理工程所组成,并且相互作用构成了地理治理。国土空间是自然与人类所共同实践的物质载体,人类被自然所塑造的程度并不亚于自身塑造自然的程度,以人地耦合系统为核心的地理系统理论成为国土空间规划与整治修复的理论基础。基于人地耦合系统的国土空间重塑最终以地理治理的形式反映在人类作用于自然环境的各种活动中。经过改革开放40年的发展,中国国土空间已基本形成了较为稳定的格局,形成了经济区、贫困区、小城镇为主的三种形态空间。中国的城镇化发展与发达国家有所不同,是城市化、城镇化、乡村化“三化耦合”并存的状态。必须重视泛第三极、环中国南海、东北亚—北极等以“一带一路”全球空间为基础的战略区域研究。基于人地耦合系统理论与国土空间价值均衡理论,国土空间重塑的基础科学问题是人地耦合系统演化机理与驱动机制。国土空间规划可以划分为三种类型:发展型规划、控制型规划和修复型规划。国土空间的保护与治理包括以土地利用为核心的国土空间全域整治,以生态文明为核心的国土空间系统修复,以社会和谐为核心的国土空间综合治理。人地耦合系统最终的发展目标是形成人类与自然相互作用的命运共同体。 相似文献
170.
闽三角城市群自然资本损失评估 总被引:3,自引:1,他引:2
在快速城镇化进程中,城市群发展在促进区域经济竞争与合作的同时,也在一定程度上造成人地关系矛盾的加剧,生态系统服务水平下降。为了量化城镇化对自然资本产生的变动,揭示人类资源消耗过程对区域生态系统服务的影响机制,以快速城镇化的典型区域——闽三角城市群为例,运用能值分析方法与GIS技术,分析了2000-2015年闽三角城市群可更新资源时空演变特征,城镇化进程中生态环境价值演变规律以及土地转化过程中的自然资本损失。研究结果表明:(1)闽三角城市群可更新资源在时间上呈波动减小趋势,空间上自沿海区域向内陆区域逐渐升高;(2)高环境质量等级中城镇用地面积占比呈显著增加趋势,由0增加到10.63%,人类活动导致区域生态环境价值的损失逐渐上升;(3)城镇化过程中由于城市空间扩张,使部分自然用地与农业用地转化为城镇用地,转化过程造成的自然资本损失总量为1.27×1022 seJ,货币价值超过6.30×109元。研究有助于完善城镇化影响下的生态环境效应研究,为城市群或区域生态环境管理与修复提供决策参考。 相似文献