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31.
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
32.
George Mulamoottil Robert Farvolden 《Journal of the American Water Resources Association》1975,11(3):599-604
ABSTRACT: By field investigations and planning, it is profitable to rehabilitate gravel pits as recreational lakes in urban areas. Some of the important aspects to be considered are topography, soil, surface water and groundwater. A case study is presented and some general guidelines in the rehabilitation process are given. This kind of a use for derelict land is important at the present time as there is a growing demand for recreational lakes in urban areas. 相似文献
33.
Geomorphologically appropriate rehabilitation measures were proposed to enhance the in-stream environment of the lowland River Idle, north Nottinghamshire, UK. However, the River Idle has multi-functional management requirements including those of flood defence so environmental enhancement must be pursued without significantly increasing the flood risk. Hydraulic testing of rehabilitation proposals is complicated because of the stringent assumptions about flow and morphology in ‘traditional’ hydraulic models. While new generation two- and three-dimension hydraulic models may overcome some of these problems, they are extremely data intensive, require advanced modelling capabilities and are, therefore, very expensive to apply. Also, they do not yet predict morphology-flow interactions adequately. As an alternative, several simple hydraulic models were applied to test the rehabilitation proposals, based on a fitness-for-purpose criterion.BENDFLOW was applied to fine tune the optimal siting of measures and to estimate the additional near-bank scour generated by proposed bend re-profiling. HMODEL2 and the FCFA method were used to test the impact on local channel conveyance capacities and HECRAS was applied to simulate the impact of the proposals on regional flood defence. Indicative results from the testing suggested a maximum increase in near-bank scour of 0·15 m in re-profiled bends, a loss of approximately 10% in flood conveyance locally due to deflector installation or reed and tree planting, and a 0·12 m increase in flood stage within the reach for a 15 year flood. The modelling results were acceptable to the management authority as an indication of an acceptable compromise between flood defence and conservation interests, and construction of the measures followed in 1996. It is clearly that it will require the results of post-project monitoring to indicate whether compromises made to the rehabilitation initiatives in order to satisfy flood defence requirements have unduly reduced their environmental enhancement potential but, for assessing the proposed methods, the models are recommended for use other lowland river environments. 相似文献
34.
在分析长江流域1998 年洪水灾害与生态环境破坏的关系的基础上,提出了生态重建规划应以可持续发展为指导思想,坚持经济建设、社会发展与生态环境保护相协调的基本原则;指出了生态保护、恢复、重建的要点与方略;提出了防灾、减灾的对策建议。 相似文献
35.
贵阳市土壤地球化学背景与生态环境分析 总被引:1,自引:0,他引:1
通过1∶250 000多目标区域地球化学调查,获得了贵阳市及邻区表、深层土壤中54项化学指标的地球化学背景值、基准值等参数。研究区总体土壤环境呈中偏酸性,对生态环境影响较大。土壤化学物质组成丰富,地球化学背景分布不均匀。除活动性强的化学组分对成土母质有分异外,多数化学组分对成土母质继承性显著。表层土壤有机碳、全碳、硫、氮、硒、氟和汞、镉、砷等的地球化学背景值显著高于深层土壤和我国其它城市地球化学基准值。前者适宜发展生态富硒特色农业,后者表明土壤环境安全形势严峻。土壤地球化学背景为生态环境评价和其它相关学科研究提供了科学基础,由此提出生态环境保护和利用建议。 相似文献
36.
This paper examines the temporal change and spatial variation of population pressure on the ecological environment in China. We have collected sufficient data from the statistical yearbooks of 31 provincial administrative areas in 1990, 1995, 2000, 2005, and 2010. Using a geographic information system (GIS) and relevant models, we analyzed the trend of the population pressure on ecological environment and the change of the gravity center of ecological environment quality. We conclude that: (1) generally, population pressure on the ecological environment in China was becoming higher during 1990–2010, especially in some areas where the population and environment were in serious imbalance and the ecological environment experienced severe pollution; (2) during a certain period, population pressure on the ecological environment was becoming lower in some areas, but the ecological environment was getting worse; (3) the areas with super-high population pressure on the ecological environment were Beijing, Tianjin, and Shanghai; (4) the gravity center of population pressure on the ecological environment and the center of ecological environment quality move differently during the study time period, but the general trend was similar – both of them were moving from west to east. Based on the analysis, this paper also provides some policy suggestions on the control of ecological environment quality. 相似文献
37.
垃圾填埋场建设项目的主要环境问题包括:渗沥液排放、地下水环境污染、大气环境污染、噪声污染、景观变化和环境安全。根据工作经验,建立了包括建设项目基本情况、生态环境影响、社会环境影响、生态环境保护措施四大类调查监测指标为核心的环保验收调查指标体系,提出了文件资料核实、现场勘查、遥感调查、公众意见调查、环境监测和摄影法为主的建设项目竣工环保验收调查技术方法。 相似文献
38.
39.
Since 1997whenChinesePresidentJiangZeminadvocatedthereconstructionofabeau tifulareaoftheNorthwest,aheateddriveofeco environmentalconstructionwiththethemesof“ecologicalagriculture”and“ecologicalrehabilitation”hasbeenlaunched .Howisthewesternagriculturetome… 相似文献
40.
ABSTRACT: Toxicity testing is a means of establishing the environmental risk of a uranium tailings release. It is valuable in designing tailings containment structures because it assists in setting acceptable levels of risk for the design. This paper presents details of toxicity tests of the tailings from Ranger Uranium Mine, Northern Territory, Australia. The results suggest that the non-radiological toxicity of the tailings is low. The environmental risk of a tailings release is more likely to be related to the physical impacts of the tailings, including infilling of billabongs and changes in the sedimentology of riparian ecosystems rather than their biogeochemical impact. Two major results were: (1) water from treatment with washed tailing fines were not toxic to Hydra viridissima, and (2) mixtures of washed tailings fines and natural floodplain sediment (overlying water or elutriates) were not toxic to Hydra viridissima or Moinodaphnia macleayi. 相似文献