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81.
本文介绍了遥感技术在滑坡的现状调查和防治中的应用.提出了航天、航空遥感图像上滑坡现状、规模、易滑地点、稳定性评价等的直接和间接判读标志;并展望了遥感技术在滑坡动态监测中的应用前景. 相似文献
82.
ABSTRACTPublic participation in the form of public meetings and written submissions has been criticised as a democratic ritual that fails to give citizens a real voice in government decisions. Participatory mapping and community surveys are alternative public participation (PP) methods that can augment legally required processes for land use planning. To date, there has been little evaluation research comparing the information content generated by required PP processes and alternative PP sources with respect to local land use decisions. Using multiple development projects from a case study community, we analysed and compared information generated from three different sources of public participation: (1) formal public comment (written submissions), (2) responses to community survey questions, and (3) land use preferences generated from participatory mapping. We found public comment strongly supported development while results from survey questions and participatory mapping methods revealed community ambivalence. The differences in public opinion are attributed to two key factors: the representativeness of participants in the PP process and the specific methods used for measuring public opinion. Community surveys and participatory mapping generated more accurate and representative community information compared to the formal PP process which was characterised by lower participation and vulnerability to special interest manipulation. For local government decision makers, the political risk of broadening PP information appears high relative to the risk of inaccurately assessing public opinion thus limiting adoption of alternative PP methods such as participatory mapping. 相似文献
83.
A reproductive-health knowledge, attitudes and practices (KAP) survey was carried out among 468 Afghan women of reproductive age. A convenience sample of women was selected from attendees in the outpatient departments of four health facilities in Kabul. Seventy-nine per cent of respondents had attended at least one antenatal consultation during their last pregnancy. Two-thirds (67 per cent) delivered their first child between 13 and 19 years. The Caesarean-section rate was low (1.6 per cent). Two-thirds (67 per cent) of deliveries occurred in the home. The contraceptive prevalence rate was 23 per cent (16 per cent modern and 7 per cent natural methods). Twenty-four per cent had knowledge of any STIs, although most of these women did not know correctly how to prevent them. Most of the women (93 per cent) needed authorization from their husband or a male relative before seeking professional health-care. In multivariate analysis, women's schooling was significantly associated with antenatal-care attendance (AOR 4.78), institutional delivery (AOR 2.29), skilled attendance at birth (AOR 2.07) and use of family planning (AOR 4.59). Reproductive-health indicators were noted to be poor even among these women living in Kabul, a group often considered to be the most privileged. To meet the reproductive-health needs of Afghan women, the socio-cultural aspects of their situation--especially their decision-making abilities -- will need to be addressed. A long-standing commitment from agencies and donors is required, in which the education of women should be placed as a cornerstone of the reconstruction process of Afghanistan. 相似文献
84.
The Platte River Basin consists of tributaries largely in Wyoming, Colorado and Western Nebraska, with the main stem in Central Nebraska. Critical wildlife habitat on the main stem requires additional in-stream flows. The watershed is one hosting multiple resources, a variety of users, and managed by an array of state and federal agencies. This study proposes a basis for securing in-stream flows for the Platte River. Candidate water supply mechanisms are suggested based on the way in which Casper, Wyoming secured water for its municipal needs. Canal lining is compared to a dam project, increasing reservoir storage, and purchasing water rights, with consideration also made for water pricing to reduce municipal use. Comparisons are based on economic efficiency, potential water conservation, and property rights criteria. Canal lining, coupled with demand management, is shown to conserve water best, given the set of efficiency and cost criteria for in-stream flow enhancement. The approach offers an opportunity to organize the water supply choice context in a transboundary watershed when quantitative information is limited. 相似文献
85.
Forest Perception and Knowledge of Hikers and Mountain Bikers in Two Different Areas in Northwestern Switzerland 总被引:1,自引:1,他引:0
Recreational activities can have major impacts on vegetation and wildlife in frequently visited forests. We assessed forest perception and knowledge (state, functions, and species diversity) among hikers and mountain bikers in a frequently visited, seminatural suburban recreation forest (Muttenz) and in a more distantly situated, naturally grown excursion forest (Wasserfallen) in northwestern Switzerland. In all, 239 hikers and 126 mountain bikers were interviewed. Mountain bikers in both forests and hikers in the more intensely used recreation forest at Muttenz assessed the state of the forest less optimistically and showed a higher awareness of the negative impact of recreational activities on the flora and fauna than hikers at Wasserfallen. Furthermore, mountain bikers seemed aware of the social conflicts caused by their activity, since they appreciated neutral or positive encounters with other forest visitors. In contrast, 57% of hikers at Muttenz reported on negative experiences with other forest visitors, particularly with mountain bikers. In general, the interviewees ecological and biological forest knowledge (forest type and function, species diversity) was rather high. A large proportion was aware of the pros and cons of different forest conditions for plants and animals, and could name or recognize at least some plant and/or animal species typical for the visited forest. The forest knowledge was neither influenced by the type of recreational activity carried out nor by any aspect of forest visit behavior (frequency and duration of forest visits, means of transportation and travel distance to forest). However, the interviewees forest knowledge was influenced by their age and educational level. 相似文献
86.
Evaluation of groundwater and soil pollution in a landfill area using electrical resistivity imaging survey 总被引:8,自引:0,他引:8
Landfills are sources of groundwater and soil pollution due to the production of leachate and its migration through refuse.
This study was conducted in order to determine the extent of groundwater and soil pollution within and around the landfill
of Seri Petaling located in the State of Selangor, Malaysia. The condition of nearby surface water was also determined. An
electrical resistivity imaging survey was used to investigate the leachate production within the landfill. Groundwater geochemistry
was carried out and chemical analysis of water samples was conducted upstream and downstream of the landfill. Surface water
was also analyzed in order to determine its quality.
Soil chemical analysis was performed on soil samples taken from different locations within and around the landfill in the
vadose zone (unsaturated zone) and below the water table (in the soil saturated zone). The resistivity image along line L–L1 indicated the presence of large zones of decomposed waste bodies saturated with highly conducting leachate. Analysis of trace
elements indicated their presence in very low concentrations and did not reflect any sign of heavy metal pollution of ground
and surface water or of soil.
Major ions represented by Na, K, and Cl were found in anomalous concentrations in the groundwater of the downstream bore hole,
where they are 99.1%, 99.2%, and 99.4%, respectively, higher compared to the upstream bore hole. Electrical conductivity (EC)
was also found in anomalous concentration downstream. Ca and Mg ions represent the water hardness (which is comparatively
high downstream). There is a general trend of pollution towards the downstream area. Sulfates (SO4) and nitrates (NO3) are found in the area in low concentrations, even below the WHO standards for drinking water, but are significantly higher
in the surface water compared to the groundwater. Phosphate (PO4) and nitrite (NO2), although present in low levels, are significantly higher at the downstream. There is no significant difference in the amount
of fluoride (F) in the different locations. In the soil vadose zone, heavy metals were found to be in their typical normal
ranges and within the background concentrations. Soil exchangeable bases were significantly higher in the soil saturated zone
compared to the vadose zone, and no significant difference was obtained in the levels of inorganic pollutants. With the exception
of Cd, the concentration ranges of all trace elements (Cu, Zn, Cr, Pb, and Ni) of Seri Petaling landfill soils were below
the upper limits of baseline concentrations published from different sources. 相似文献
87.
Yuichi Moriguchi 《Journal of Material Cycles and Waste Management》2007,9(2):112-120
This article reviews recent progress in material flow analysis and its use in providing resource productivity indicators and
is based on developments in Japanese policy toward a sound material-cycle society and in international forums such as within
the Organisation for Economic Development and Cooperation, covering both institutional and methodological issues. Indicators
derived from economy-wide material flow accounts such as direct material inputs are useful to demonstrate the absolute size
of a physical economy and to reinforce the need to both reduce consumption of natural resources and limit waste generation.
Interpretation of material flows as resources and potential environmental impacts is discussed, and linkages between the size
of material flows and specific environmental impacts and damage must be further elaborated for use in environmental policy.
Lessons learned from the practical use of resource productivity indicators are also discussed. Additional indicators are needed
that can be used to evaluate the performance of microeconomic contributors. The need for an integrated approach that links
upstream resource issues and downstream waste issues through the 3Rs concept or the circular economy/society concept is attracting
increasing attention. Consequently, the accumulation of reliable scientific knowledge and data in this field in a fully international
context is essential. 相似文献
88.
Gary L. Larson 《Environmental management》1980,4(2):105-110
Since the presentation of the Leopold Report (Leopold et al. 1963) to the United States Secretary of the Interior, recommendations in the document for managing natural park resources on the ecosystem level have been included in the management policies of the National Park Service. In many instances, however, management programs have continued to focus on individual resource problems, without apparent concern for the ecological consequences on ecosystems. Without knowledge of the interrelationships of ecosystem components, solving one problem may result in other resource problems. Graphic approaches are presented as potential tools to view these complex interrelationships relative to the needs of the resource manager. Interpreting the dynamics of aquatic systems is emphasized. 相似文献
89.
This paper contributes to on-going attempts at bringing together two influential ideas in water governance: Integrated Water Resource Management (IWRM) and adaptive governance. In particular, a tension remains between the call in IWRM for the use of formal institutions, such as river basin organisations, to secure public policy integration, and the assumptions in adaptive governance in favour of informal collaboration between essentially independent policy actors. To clarify this relationship, this article draws on theoretical research on public policy integration, and uses these insights in an empirical setting to identify mechanisms that can facilitate effective policy integration for adaptive water governance. The research is based on recent attempts in Scotland to implement IWRM ideas to improve flood management. Several governance mechanisms were adopted to facilitate the integration of flood, water and rural land use policies. Six Scottish policy regimes are analysed using documentary sources and interviews. Results challenge the idea that collaboration should primarily be built on either river basin organisations or informal mechanisms. We identify a mix of informal and statutory-based mechanisms which may secure political and technocratic commitment to policy integration. 相似文献
90.