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181.
The literature guides environmental planning and, specifically, how to use ecological rehabilitation projects to achieve long-term
planning goals and landscape-scale environmental sustainability. There is, however, a perceived gap between principles in
the literature and the use of them by practitioners involved in smaller-scale ecological rehabilitation projects. Using interviews
with practitioners involved in 11 projects within the Regional Municipality of Waterloo, Ontario, Canada, we tested whether
practitioners used five principles for effective planning and implementation of ecological rehabilitation that we derived
from the literature. These five principles were: establishing political and ecological context, using ecologically appropriate
objectives and practices, using comparative multidisciplinary and cross-scale approaches, using adaptive planning and implementation,
and establishing good communication within and external to projects. Few projects followed all five principles, and practitioners
indicated that they used three more project-specific principles: obtaining political/social support, promoting projects and
changing attitudes about projects, and securing sufficient and persistent funding to maintain a project's life. While the
literature emphasizes that ecological rehabilitation is only effective if projects are coordinated on a watershed basis, most
practitioners focused solely on the goals of their specific project. The gap between literature and practice may arise because
most practitioners are new to the field of ecological rehabilitation and still are focused on the methods involved. Time pressures
force practitioners to obviate the literature and get projects started quickly, lest support evaporate. Complicating these
difficulties is decreased support from federal and provincial governments for large-scale environmental planning. It is unclear
whether ecological rehabilitation projects in Waterloo Region (at least) will ever become effective at promoting landscape-scale
ecological goals or remain smaller-scale stop-gaps. 相似文献
182.
Numerous analyses of the possible impacts of future climatic changes on tree species composition have been published for
both lowland and high-elevation forests. Most of these studies were based on the application of forest "gap" models, and the
vast majority of them considered only changes in the average of climatic parameters over time. In this study, we use a unique
data set on reconstructed past climatic variations to analyse forest dynamics simulated by the forest gap model ForClim. This
analysis forms the basis for a systematic exploration of the ecological effects of changing means vs. changing variability
of climate on central European forests. A reconstruction of historical climate covering the last 470 years in the Swiss lowlands
(ClimIndex) is extrapolated to a transect across the alpine (cold) treeline and used to simulate the influence of climate
variations on the time scale of decades on forest biomass and tree species composition at both sites. While the simulation
at the low-elevation site shows little sensitivity to climate variations, the results from upper subalpine forests suggest
that two major dieback events would have occurred at elevations above the current but below the climatic tree line, induced
by clusters of exceptionally cold summers. The results are in agreement with available dendrochronological data and with documentary
evidence on massive negative impacts on flora and fauna at high elevations during these periods. We conclude that ForClim
is capable of capturing the effects on tree population dynamics of climate variability at these sites as reconstructed from
the ClimIndex record. A factorial design is used to address the sensitivity of ForClim to changes of the long-term averages
vs. changes of the variability of monthly temperature and precipitation data. To this end, the simulated tree species composition
of near-natural forests is examined along a climate gradient in Europe. The results indicate that there are three types of
forest response: (1) little sensitivity to both kinds of change, (2) strong sensitivity to changes in the means, but little
sensitivity to changing variability, and (3) strong sensitivity to changing variability at least in parts of the examined
climate space. Half of the cases investigated fall under the third category, suggesting that emphasis should be placed on
also assessing the sensitivity of ecosystems to future changes in climate variability rather than on changes of average values
alone.
Electronic Publication 相似文献
183.
长江流域生态环境的保护与生态城市建设 总被引:7,自引:3,他引:4
从城市经济系统来看,生态城市既要保证经济的持续增长,更要保证增长率的质量。也就是说,生态城市要有合理的产业结构、能源结构和生产而局,使城市的经济系统和生态系统能协调发展,形成良性循环,实现城市经济社会与生态环境效益的统一。长江流域生态环境的恶化已经严重影响到整个长江流域经济的发展。长江流域生态城市建设就是把环境发展与生产力发展联系起来是以各大城市生态建设为主导把各个大城市建设成为全流域的生态城市中 相似文献
184.
航空安全风险管理模式探讨 总被引:5,自引:0,他引:5
航空安全需要动态管理,因此构建并实施基于问题管理的航空安全风险管理模式就非常有意义。本文探讨了航空公司、机场和空管的安全管理工作如何围绕航空安全问题为中心进行制度、组织、日常管理构建,注重问题的识别、分析和解决,切实有效的地解决安全问题。实施安全问题管理变专职安全管理为全员安全管理;变间接安全管理为直接安全管理;变滞后安全管理为超前安全管理;变僵化安全管理为创新安全管理;变被动安全管理为主动安全管理;变模糊安全管理为务实安全管理。无疑这种管理模式均适合民航三大主体的安全管理需求。 相似文献
185.
通过将分区疏散转化为分配问题(Allocation Problem),并采用启发式的A*优化算法,对人员位置固定的公共场所分区疏散进行研究。进一步利用基于元胞自动机模型的大型公共场所人员疏散行为模拟仿真系统,在充分考虑公共场所中每个人员的状态、人员之间以及人员与周围环境的相互作用的前提下,对疏散分区的效果进行模拟;通过与未分区的模拟结果相比较,可以认为,分区疏散有助于人员快速疏散,大大缩短整体避难时间,而且基于移动路径搜索的分区更加切合实际。 相似文献
186.
David M. Greer 《Environmental management》1982,6(3):217-229
An urban population of ducks in Puyallup, Washington, USA was studied for 14 consecutive months beginning in November 1978. Observations were made weekly from four study sites where ducks would congregate at early morning hours. Factors contributing to the presence of waterfowl in Puyallyup included abundant food supplies and a creek corridor that connected fragmented habitats in the urban area to the larger rural populations of waterfowl. Mallards (Anas platyrhynchos) were the most abundant of the 13 species observed and were the only ducks remaining during the nesting season. Habitat size and complexity were important factors influencing the species diversity of a particular site. Nesting success of mallards was poor due to limited distribution of nesting habitat, intraspecific aggression, and human disturbance. Both site-specific and more broad-based strategies are suggested for managing and planning for duck populations in urban areas. 相似文献
187.
Early research showed that citizens’ environmental concern in the United States was linked to three individual-level factors: socio-demographic variables, political orientations, and personal beliefs or worldviews about human-nature relations. Given many changes in the American society over the last several decades, one important, yet unanswered question is whether these factors still drive public environmental concern in the United States today, and if so, to what extent. This study, drawing from extant theoretical and empirical studies, aims to reinvestigate the determinants of citizens’ environmental concern by employing three national public surveys conducted in 2004, 2007, and 2013. Our data analyses confirm and expand the findings of previous research on the significance and importance of political ideology, fundamental beliefs about human-nature relations, and certain socioeconomic factors such as gender and race in explaining citizens’ environmental concern. More specifically, political liberals, people with higher New Ecological Paradigm values, females, and Non-Whites tend to be more concerned about environmental problems than their counterparts are. Our data analyses also reveal some interesting findings when compared to many previous studies: first, our data indicate a positive relationship between age and environmental concern, suggesting that older people in the United States are more concerned about the environment than younger adults; second, unlike most past research showing a positive Education-Environmental Concern relationship, our study suggests that education level seems to have little effect in explaining citizens’ environmental concern measured in this study. Key implications for environmental policymaking and recommendations for future research are discussed in the conclusion. 相似文献
188.
基于参与式社区评估法的泾河流域景观管理问题分析 总被引:3,自引:0,他引:3
参与式社区评估法既兼顾了景观管理中的地理变量,同时还将社会经济因素纳入了考虑范畴,是深入进行问题分析客观有效的方法之一。本文采用参与式社区评估法,运用问题矩阵和问题树分析,对泾河流域景观管理中存在的问题和利益相关者的认知进行了分析。研究发现,绝大多数利益相关者认为土壤侵蚀已成为第一严重的问题,其次是土地生产力低下、自然灾害、植被破坏等。尽管当地公众已经认识到了土壤侵蚀的严重危害,但在安排土地利用方式时,却很少考虑土壤侵蚀带来的危害,仍然从事着自给自足的粮食生产活动。 相似文献
189.
Jukka Lehto Jussi Paatero Reijo Pehrman Seija Kulmala Juhani Suksi Teija Koivula Timo Jaakkola 《Journal of environmental radioactivity》2008,99(10):1656
Lichen–soil column samples were taken from several locations in the Southern Finland between 1986 and 2006. Columns were divided into three parts, upper lichen, lower lichen and underlying soil, and their gamma emitting radionuclides, 134Cs, 137Cs, 103Ru, 95Zr, 106Ru, 110mAg, 125Sb and 144Ce, were measured with gamma spectrometry. Deposition values were calculated as Bq/m2 for each sampling site. Distribution of various radionuclides in the three compartments as a function of time was determined. Both effective and ecological half-lives of all radionuclides were calculated for upper lichen, whole lichen and whole lichen–soil column. A linear relation was derived between the physical half-lives and effective half-lives for whole lichen and for whole lichen–soil column. Reindeer meat activity concentrations of various radionuclides and ensuing radiation doses to reindeer-herding people were also estimated for a hypothetical case where a similar high radioactive pollution, as was taken place in the Southern Finland, would have occurred in the reindeer-herding areas in the Finnish Lapland. 相似文献
190.
Qinhua Fang Luoping Zhang Huasheng Hong Liyu Zhang Frances Bristow 《Environment, Development and Sustainability》2008,10(1):41-49
Environmental planning at different levels has been called for by environmental departments in China during last years to
integrate environment consideration to economic development. Based on the accomplished environmental planning practice in
Xiamen China, the paper suggests a general environmental planning process with ecological function zoning as its key steps,
at the same time an effective method for ecological function zoning was formulated. The case studies of Dongfu suburban town
environmental planning and Xiamen eco-city conceptual planning indicate that scientifically sound results of ecological function
zoning can contribute to improving not only the adaptability and acceptability of environmental planning, also the environmental
management and the decision-making. The experience shows that the ecological function zoning methods should be applied according
to the principles of adaptive management, resource-based and community-based, so that it can integrate science into decision-making
process, avoiding both narrow-minded viewpoints of planners and natural resource use conflicts among variety of stakeholders.
Problems to be resolved in the future are also pointed out in the ending part. 相似文献