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2014年7月,采集长江嘉陵江重庆段9个断面的地表水和沉积物样品,检测15种多环芳烃(PAHs)含量.结果表明,地表水的∑PAHs浓度范围为65.6-1249 ng·L-1,沉积物中∑PAHs浓度范围为68.6-4226 ng·g-1,与其历史浓度水平相当;聚类分析表明,化工园区对其下游PAHs分布有一定影响,园区下游地表水和沉积物∑PAHs浓度最高.两江汇流前,地表水4环PAHs占总量的43.63%-61.68%;两江汇流后,2环比例增加,占总量的29.01%-68.72%;沉积物4环PAHs占总量的26.62%-48.74%.在顺流方向,地表水中河左∑PAHs浓度高于河中和河右,沉积物中∑PAHs浓度横向无明显差别,其中化工园区下游可能是受左岸工业影响,地表水中河左∑PAHs浓度是河中、河右的12倍和7倍,沉积物中河左∑PAHs浓度是河右的7倍.环数组成、分子比值和主成分分析表明研究区域地表水PAHs来源主要为木材、煤燃烧源,同时还包括石油燃烧和石油泄漏,沉积物则主要为木材、煤高温燃烧源. 相似文献
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Daşdemir I 《Environmental management》2005,35(3):247-257
The purpose this study was to improve operational planning and management of national parks in Turkey to balance conservation use and sustainable management. Souksu National Park (SNP) was chosen as the study area. The data were obtained from interviews of 182 visitor groups (in total, 819 people) and analyzed using correlation, factor, discriminant, and regression analyses. It was found that the most important factors affecting operational planning and management of SNP are (1) travel cost, (2) visitor welfare level, (3) intensity of use, (4) size of visitor group, (5) type of recreational demand. The main source of visitors to SNP is from a zone within a 0–90-km radius. This region comprised 53.85% of total visitors to the park. The capital of Turkey (Ankara) is the most important source of visitors from within this zone. The optimum activity mix in SNP is also determined. Picnicking, viewing the scenery, and nature walks or trekking comprised the main uses of the park. It is anticipated that these findings will help to improve operational planning and sustainable management of the national park and the environment. 相似文献
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《Journal of Environmental Planning and Management》2012,55(12):2151-2165
The study examines the relationship between nature management and land use planning in order to balance nature protection and tourism development within and outside national park borders. Applying theory about local networks and social learning, we highlight how responsible actors coordinate in order to strike a balance between protection and tourism. Based on this study of a Norwegian coastal national park, we state that competent key individuals are crucial preconditions for fulfilling the management and planning objectives in a wider regional context. In our case study, such personnel within the national park management and municipal land use planning system serve as bridge builders between nature protection and tourism. However, we argue that the existing management system is very vulnerable, and an important implication of our study is that the present local network should be more firmly institutionalized in order to become sufficiently robust and resistant to changes. 相似文献
35.
Whether and how environmental management can create enterprise value is intensively debated. There are a number of concepts that aim to link environmental management and enterprise value. These concepts are usually based on net present value approaches such as Rappaport's (1986) shareholder value model. What is usually overlooked is that environmental management based on net present value concepts risks making companies (eco‐)efficient but vulnerable to environmental and social shocks. This article introduces the environmental option value concept as a compliment to concepts such as environmental shareholder value. As this article shows, creating environmental option value creates flexibility that allows companies to be shielded from the detrimental effects of possible future environmental and social shocks. In combination the two approaches can help environmental management to contribute to creating long‐term enterprise value. Copyright © 2005 John Wiley & Sons, Ltd and ERP Environment. 相似文献
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城市公园是城市生态环境的重要组成部分,其环境质量与人类健康息息相关.选择北京市121个城区公园,采集公园土壤样品并分析其中7种多环芳烃(PAHs)含量,评价城区公园土壤中PAHs的含量水平,并基于BP神经网络预测了2020年和2023年土壤PAHs含量.结果表明:北京城区公园土壤中w(PAHs)(7种PAHs总含量)范围为0.033~4.182 mg/kg,低于GB 36600—2018《土壤环境质量建设用地土壤污染风险管控标准(试行)》土壤污染风险筛选值,且7种PAHs的毒性当量浓度(TEQ)均低于世界卫生组织标准值(1 mg/kg),对人体健康的毒性风险较小.将14个影响指标(8个社会经济因子与6个公园特征因子)作为输入层、土壤w(PAHs)作为输出层,建立BP神经网络的拟合优度达0.845.预测结果显示,2020年和2023年北京城区公园土壤中w(PAHs)范围分别为0.008~0.969 mg/kg和0.022~1.988 mg/kg,整体均低于GB 36600—2018土壤污染风险筛选值,但随时间推移呈上升趋势,尤其朝阳区和海淀区将有大幅增长.研究显示:城市化发展因素对土壤w(PAHs)的增加有明显影响,城市发展进程影响不容忽视;至2023年,北京城区公园土壤若不加管理,其w(PAHs)将持续增长. 相似文献
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长江宜宾段工业园区中分布着众多化工企业,对周边流域生态环境具有潜在风险。选择环境风险源、管控机制、风险受体3个准则层,包括行业类型、园区企业生产工艺、环境管理体系、环境风险管理体系、受纳水体环境等13个指标层建立评估模型体系;采用层次分析法(AHP)评估了宜宾市6家工业园区(A~F)的环境风险评。结果表明,6家工业园区准则层权重总占比表现为环境风险源(69.939)>环境风险受体(38.076)>风险管控机制(33.420),各园区环境风险综合值表现为B园区(19.147)相似文献
40.
介绍了花山煤化工园区基本情况,从花山特殊的生态功能区,防护林建设产生的生态效益、社会效益、经济效益,防护林建设改变当地小气候,发挥多功能防护作用等方面阐述了建设沾益县花山煤化工园区防护林的必要性,并对其防护林的建设提出建议。 相似文献