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151.
北方湖泊水化学特征与发展态势   总被引:1,自引:0,他引:1  
通过对国家级自然保护区的核心区达里诺尔湖水环境4年的研究,得出:有着典型代表的达里诺尔北方湖泊水环境以含盐量高、碱度大为主要化学特征,而且随着生态环境的破坏、湖水蒸发量的逐年增加,湖泊水质有着明显的恶化趋势。  相似文献   
152.
立足太白山旅游发展现状,提出当前阻碍太白山旅游发展的四大问题.为了提升太白山整体旅游水平,提供可持续发展的合理途径,将太白山南、北坡相关保护单位与景区联系起来,以"南北统筹,差异开发"为指导思想,探讨在"大太白山"框架之下的旅游整体开发模式.在此基础上将大太白山旅游区划分为"两片四区",提出了相应的产品对策.  相似文献   
153.
A large copper–nickel smelter complex is located at the Kole Penninsula, Russia, close to the Norwegian border. Trace-element concentrations in surface sediments (0–0.5 cm) and pre-industrial sediments from 45 lakes in the region were used to uncover spatial deposition patterns and contamination factor of sediments. Elevated concentrations were found, especially for Ni and Cu, but also for Pb, Co, Hg, As, and Cd. Highest concentrations were found up to 20 km from the smelter, but the concentrations decreased exponentially with distance from the smelter. Increasing Ni, Cu, As, and Hg concentrations from sub-surface to surface sediments were found for lakes at intermediate distances (20–60 km). This may reflect recent changes in atmospheric depositions, as shown in nearby Norwegian areas. However, we cannot rule out that this also may have been caused by diagenetic processes, especially for the most redox-sensitive elements such as As.  相似文献   
154.
Development of plans to restore degraded areas in the Great Lakes   总被引:3,自引:0,他引:3  
The International Joint Commission's Water Quality Board has identified 42 Areas of Concern in the Great Lakes ecosystem where Great Lakes Water Quality Agreement objectives or jurisdictional standards, criteria or guidelines, established to protect uses, have been exceeded and remedial actions are necessary to restore beneficial uses. As a result of the 1985 report of the Water Quality Board, the eight Great Lakes states and the Province of Ontario committed themselves to developing a remedial action plan (RAP) to restore all uses in each Area of Concern within their political boundaries. Each RAP must identify the specific measures necessary to control existing sources of pollution, abate existing contamination (e.g., contaminated sediments), and restore all beneficial uses. Points which must be explicitly addressed in each RAP include: geographic extent of problem, beneficial uses impaired, causes of problems, remedial measures and a schedule for implementation, responsible agencies, and surveillance and monitoring activities that will be used to track effectiveness of remedial actions. The jurisdictions are responsible for developing RAPs, and the International Joint Commission is responsible for evaluating the adequacy of each RAP and tracking progress in restoring beneficial uses.  相似文献   
155.
温度和水分是影响土壤有机碳矿化的重要因素,而北方高纬度地区对气候变化响应敏感.本文选取大兴安岭多年冻土区落叶松和樟子松两种森林土壤(0~15 cm)为研究对象,通过测定不同温度(5、10和15℃)及水分(设置土壤含水率分别为30%、45%和60%)处理下的土壤有机碳矿化速率,以明确多年冻土区土壤有机碳矿化对不同梯度环境变化及其交互作用的响应.结果表明:研究区土壤累积碳矿化量为0.39~2.29 mg·g~(-1),落叶松林土壤高于樟子松林土壤,且矿化率随着培养时间延长呈先降低后稳定的趋势;土壤有机碳矿化程度随温度升高而显著增加(p0.001),但其对水分的响应因林型而异,落叶松土壤有机碳矿化程度随水分增加而降低,樟子松土壤有机碳矿化程度随水分增加而增加;温度和水分的交互作用对土壤有机碳矿化程度的影响未达到显著水平;土壤有机碳矿化的温度敏感性以土壤含水量为30%的落叶松土壤培养时最低(2.11),以土壤含水量为60%的落叶松土壤培养时最高(2.50),水分和林型对其影响不显著.  相似文献   
156.
日本阪神大震灾在应急救灾上的几点教训   总被引:4,自引:1,他引:4  
本文从防灾体制、心理准备和防灾规划等方面分析日本阪神大震灾在应急救灾行动中的教训,并结合我国的情况作了简单的讨论。  相似文献   
157.
Public participation in planning is frequently linked to ideas of environmental justice and sustainability; yet, despite the voluminous literature on the topic, the reaction of frontline planning professionals to the broadly pro-participation agendas of central and devolved government in Great Britain has not been sufficiently examined. This is important because of their role in implementing such agendas, and the space for frontline professionals to shape the contours of reform. Drawing on extensive empirical material, I explore the reaction of local authority planners to participation policies, finding divided opinion as to whether more participation is needed to improve planning, but a strong framing of participation as something requiring careful management. I conclude that planners are broadly supportive of participation so long as they are in control, which can be understood through an institutionalist perspective that suggests there will be a similar reaction to further, ongoing, efforts to make planning more participatory.  相似文献   
158.
ABSTRACT: On June 15, 1977, an unusual brightness anomaly was detected in the north arm of Great Salt Lake, Utah, on NOAA-5 Very High Resolution Radiometer (VHRR) visible band imagery and on Landsat-2 multispectral visual band imagery. Retrospective inspection of NOAA-3, 4, and 5 satellite imagery from 1974–77 revealed 12 previous cases of the anomaly, whereas post monitoring documented nine other cases through May 1978. Comparison of lake levels in the north arm with meteorological parameters leads to the conclusion that the anomalous brightness is associated with wind induced seiches in the north arm. Apparently the wind induces a lower water depth, turbulence, and mixing throughout the water column in the western third of the north arm, thus increasing the brightness of the surface waters chiefly from sediment resuspension.  相似文献   
159.
Abstract: The purpose of this article was to show how the value of recreational boating can be assessed and how that value can be linked to water levels. Data were gathered via a survey of recreational boaters to determine days boated and willingness‐to‐pay (net economic value) for boating on Lake Ontario and on the St. Lawrence River in 2002. Depth measurements were taken at marinas and yacht clubs, boat launch ramps, and private docks. Stage‐damage curves were used to pinpoint at what water levels and to what extent boaters would be impacted. Boaters recreated an estimated 1.3 million days in 2002 and spent an estimated US$178 million in New York counties bordering Lake Ontario and the St. Lawrence River. The mean net economic value per day per boat (above current expenditures) was $69.36, with an estimated total net economic value of US$90 million. Using Lake Ontario as an example, the stage‐damage curves show that the overall negative impact would be small, between 245 and 248 ft. Maintaining water levels within that range for the entire boating season would be ideal for Lake Ontario boaters and associated businesses.  相似文献   
160.
Is recycled water use risky? An Urban Australian community’s perspective   总被引:1,自引:0,他引:1  
The emergence of a global water crisis has seen the necessity for a sustainable approach to water management. Policies directed towards water recycling have been implemented in many regions of the world. In Australia, prolonged drought conditions in most major cities during the past decade have led to serious national calls for less drinking water to be used (Prime Minister’s Science Engineering and Innovation Council, 2003), and a strategic policy response from many State Governments, including bold targets for water recycling. A key consideration to the realisation of these policies is greater understanding of community attitudes to recycled water use, without which, a number of recycled water projects have failed (Hurlimann and McKay, 2004). Despite the critical nature of community attitudes, little research has been conducted, especially in relation to perception of risk, which has been found to be critical in the adoption of new technologies (Cvetkovich and Lofstedt, 1999). This paper investigates an urban Australian community’s perception of risk involved with using recycled water. Key findings include: perception of risk increased as the use of recycled water became increasingly personal. Perception of risk was significantly negatively related to trust, perception of fairness and information. Trust in the Water Authority to manage risk was significantly related to perception of trust, communication and integrity of the Authority.  相似文献   
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