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921.
天津滨海新区围海造地的生态环境影响分析   总被引:2,自引:0,他引:2  
选择具有重要典型意义的环渤海城市快速扩张地区渤海湾西岸天津滨海新区段为例,从宏观的景观格局变化与时空演变,微观尺度上的近海生态环境变化方面分析了天津滨海新区围海造地的生态环境影响。结果显示:(1)随着天津滨海新区2006年纳入国家发展战略以及总体规划的实施,围海造地面积从2004年的52.32 km2迅速增加2010年的312.78km2,规划到2020年将增加到425.94 km2,人工岸线从41.16 km增加到217.79 km,造成景观自然性急剧下降,人类对近海的干扰强度过大。(2)对纳潮量造成影响,经过围海造地,天津滨海新区段纳潮量减少了13.7%,纳潮量的减少进一步影响了污染物的稀释与扩散。(3)海洋生态功能受到影响2,010年渤海湾天津滨海新区段的近海生态服务价值将下降18%。  相似文献   
922.
美国环境健康损害赔偿立法及其对我国的启示   总被引:2,自引:0,他引:2  
美国尚未制定专门的环境健康损害赔偿立法。由环境保护法律中的相关规定、涉及环境侵权赔偿或者补偿的相关立法以及环境健康损害赔偿典型判例构成的法规体系,为环境健康保护提供了重要的法律依据。从《超级基金法》、《詹姆斯.扎德加9.11健康与赔偿法案》、《联邦侵权赔偿法》和《联邦雇员补偿法》等立法以及Sterling诉Velsicol化学公司案、普莱斯诉美国海军案等判例中总结的美国经验主要包括:适时制定专门立法;建立损害赔偿社会化机制;适用惩罚性赔偿机制;科学确定赔偿范围和数额;明确公职人员的法律责任。我国应当基于自身国情,充分借鉴美国的成熟经验,加快环境健康损害赔偿立法进程。  相似文献   
923.
Poff, Boris, Karen A. Koestner, Daniel G. Neary, and Victoria Henderson, 2011. Threats to Riparian Ecosystems in Western North America: An Analysis of Existing Literature. Journal of the American Water Resources Association (JAWRA) 47(6):1241–1254. DOI: 10.1111/j.1752‐1688.2011.00571.x Abstract: A total of 453 journal articles, reports, books, and book chapters addressing threats to riparian ecosystems in western North America were analyzed to identify, quantify, and qualify the major threats to these ecosystems as represented in the existing literature. Publications were identified either as research, policy, literature review, historical comparison, or management papers. All papers were evaluated based on year of publication, area of interest, and type(s) of threats addressed. Research papers, however, were assessed in more depth. The publications ranged from the 1930s to 2010 and addressed the following threats: dams, pollution (point and nonpoint), grazing, land use change, timber harvesting, water diversion, road construction, recreation, mining, groundwater pumping, invasive species, climate change, salinity, fire, insect and diseases, woody encroachment, watershed degradation, elimination of native vegetation, beavers, fire suppression, and fuel management. While the types of threats vary on spatial and temporal scales, some persist through decades in western North America. This analysis shows that grazing has been perceived as a dominant threat since the 1980s, but has been diminishing in the past decade, while invasive species, dams and, in recent years, climate change are increasingly represented in the literature as threats to riparian ecosystems in western North America.  相似文献   
924.
Informal (visitor-created) trails represent a threat to the natural resources of protected natural areas around the globe. These trails can remove vegetation, displace wildlife, alter hydrology, alter habitat, spread invasive species, and fragment landscapes. This study examines informal and formal trails within Great Falls Park, VA, a sub-unit of the George Washington Memorial Parkway, managed by the U.S. National Park Service. This study sought to answer three specific questions: 1) Are the physical characteristics and topographic alignments of informal trails significantly different from formal trails, 2) Can landscape fragmentation metrics be used to summarize the relative impacts of formal and informal trail networks on a protected natural area? and 3) What can we learn from examining the spatial distribution of the informal trails within protected natural areas?  相似文献   
925.
The invasion spread of the emerald ash borer (Agrilus planipennis Fairmaire) (Coleoptera: Buprestidae) is characterized by the formation of satellite populations that expand and coalesce with the continuously invading population front. As of January 2010, satellite infestations have been detected in 13 states and two Canadian provinces. Understanding how newly established satellite populations may affect economic costs can help program managers to justify and design prevention and control strategies. We estimate the economic costs caused by EAB for the 10-yr period from 2010 to 2020 for scenarios of fewer EAB satellite populations than those found from 2005 to 2010 and slower expansion of satellite populations found in 2009. We measure the projected discounted cost of treatment, removal, and replacement of ash trees (Fraxinus spp.) growing in managed landscapes in U.S. communities. Estimated costs for the base scenario with the full complement of satellites in 2005-2010 and no program to mitigate spread is $12.5 billion. Fewer EAB satellites from 2005 to 2010 delay economic costs of $1.0 to 7.4 billion. Slower expansion of 2009 satellite populations delays economic costs of $0.1 to 0.7 billion. Satellite populations that are both distant from the core EAB infestation and close to large urban areas caused more economic costs in our simulations than did other satellites. Our estimates of delayed economic costs suggest that spending on activities that prevent establishment of new satellite EAB populations or slow expansion of existing populations can be cost-effective and that continued research on the cost and effectiveness of prevention and control activities is warranted.  相似文献   
926.
927.
陈菁  彭金龙  徐彦森 《环境科学》2021,42(9):4071-4082
细颗粒物(PM2.5)和臭氧(O3)是我国的主要大气污染物,严重危害人群健康.北京市自2013年以来大力开展大气污染治理工作,现已取得显著成效.通过分析2014~2020年北京市34个大气环境监测站的PM2.5和O3浓度变化特征并评估大气污染防治的健康效应,对推进大气污染防治具有重要意义.结果表明,2014年北京市PM2.5年均值和4~9月平均O3日最大小时(O3_max)值分别为92.0 μg·m-3和81.9 nmol·mol-1.2014~2020年PM2.5平均每年降低7.5 μg·m-3,但是O3_max持续偏高.在季节尺度,冬季的12月和1月PM2.5浓度最高,夏季的8月浓度最低.相反地,O3_max在每年6月浓度最高.PM2.5浓度日变化规律为,夜间22:00至次日00:00最高,14:00~16:00最低.而O3浓度在07:00最低,随后逐步升高并在午后达到最高.在空间分布上,PM2.5在2014和2019年都呈现南高北低的趋势,O3_max在全市范围内均较高,仅在道路区域偏低.大气污染对人群健康影响的评估结果表明,2014年北京市与PM2.5相关的心血管和呼吸道疾病超额死亡人数分别为1580人和821人,与O3相关的呼吸道疾病超额死亡人数为2180人.2019年与PM2.5相关的超额死亡人数仅为2014年的50%,而与O3相关的超额死亡人数与2014年持平.北京市细颗粒物治理成效显著,但是O3污染问题凸显,O3已经成为危害北京市居民健康的首要大气污染物.未来需要加强PM2.5和O3协同治理.  相似文献   
928.
The COVID-19 pandemic has brought profound social, political, economic, and environmental challenges to the world. The virus may have emerged from wildlife reservoirs linked to environmental disruption, was transmitted to humans via the wildlife trade, and its spread was facilitated by economic globalization. The pandemic arrived at a time when wildfires, high temperatures, floods, and storms amplified human suffering. These challenges call for a powerful response to COVID-19 that addresses social and economic development, climate change, and biodiversity together, offering an opportunity to bring transformational change to the structure and functioning of the global economy. This biodefense can include a “One Health” approach in all relevant sectors; a greener approach to agriculture that minimizes greenhouse gas emissions and leads to healthier diets; sustainable forms of energy; more effective international environmental agreements; post-COVID development that is equitable and sustainable; and nature-compatible international trade. Restoring and enhancing protected areas as part of devoting 50% of the planet’s land to environmentally sound management that conserves biodiversity would also support adaptation to climate change and limit human contact with zoonotic pathogens. The essential links between human health and well-being, biodiversity, and climate change could inspire a new generation of innovators to provide green solutions to enable humans to live in a healthy balance with nature leading to a long-term resilient future.  相似文献   
929.
本文通过分析“淮河流域环境与健康监测网”获取的环境监测科学数据特征,并结合我国环境监测科学数据共享的现状和存在的问题,根据环境监测科学数据的5个基本要素,对构建面向社会公众、面向科学研究的多部门环境监测科学数据共享体系进行了探索研究.  相似文献   
930.
It is commonly recognized that there are constraints to successful regional-scale assessment and monitoring of cumulative impacts because of challenges in the selection of coherent and measurable indicators of the effects. It has also been sensibly declared that the connections between components in a region are as important as the state of the elements themselves. These have previously been termed “linked” cumulative impacts/effects. These connections can be difficult to discern because of a complicated set of interactions and unexpected linkages. In this paper we diagnose that a significant cause of these constraints is the selection of indicators without due regard for their inter-relationships in the formulation of the indicator set. The paper examines whether the common “forms of capital”, i.e., natural (renewable and non-renewable), manufactured, social, human and financial capitals, framework is a potential organizing structure. We examine a large region in western NSW Australia where the predominant production systems are mining and grazing for production of wool, beef and lamb. Production in both is driven by consumption of a non-renewable resource, i.e., ore for mining and topsoil for grazing, the latter on the basis that loss rate estimates far exceed soil formation rates. We propose that the challenge of identifying connections of components within and between capital stores can be approached by explicitly separating stores of capital and the flows of capital between stores and between elements within stores, so-called capital fluxes. We attempt to acquire data from public sources for both capital stores and fluxes. The question of whether these data are a sufficient base for regional assessment, with particular reference to connections, is discussed. The well-described challenge of a comparative common currency for stores and fluxes is also discussed. We conclude that the data acquisition is relatively successful for stores and fluxes. A number of linked impacts are identified and discussed. The potential use of money as the common currency for stores and fluxes of capital is considered. The basic proposition is that replacement or preservation costs be used for this. We conclude that the study is sufficiently positive to consider further research in fully-coupled models of capital stores and fluxes.  相似文献   
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