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181.
于2014年5—9月逐月对青岛世园会园区内的天水水库进行了浮游植物群落结构研究,共发现浮游植物7门42属66种,密度变化范围为18.48×104~427.00×104个/L,优势种为克罗脆杆藻(Fragilaria crotonensis)、铜绿微囊藻(Microcystis aeruginosa)和尖尾蓝隐藻(Chroomonas acuta),监测期间浮游植物密度逐渐升高,均匀度和多样性指数呈下降趋势。聚类结果显示,监测区域大致可按月分为3个浮游植物群落,分别为绿藻型、硅藻-隐藻型、蓝藻型。冗余分析表明,氨氮、CODMn及总氮与水库浮游植物的群落结构关系最为密切。水质评价显示,天水水库水质处于中度污染,营养水平为中营养。  相似文献   
182.
We introduce consistent conjectures into Barrett (1994) canonical model of international environmental agreements. The existing literature assumes inconsistent Nash conjectures, despite the fact that policymakers recognize that abatement levels are strategic substitutes and increases in abatement generate carbon leakage. With consistent conjectures much of the conventional wisdom is reversed. The non-cooperative abatement level is below the Nash equilibrium. The difference between Nash and consistent conjectures is greatest when benefits are large and costs are small. We find that large coalitions cannot form. However, small coalitions can result in substantial increases in abatement relative to the non-cooperative outcome.  相似文献   
183.
The on-going introduction of non-native species to Antarctica due to expanding human activity presents an increasing threat to biodiversity. Under the Protocol on Environmental Protection to the Antarctic Treaty, all introduced non-native species should be removed from the Antarctic Treaty area. The non-native grass Poa pratensis was first introduced to Cierva Point (Danco Coast, Antarctic Peninsula), along with substantial quantities of non-Antarctic soil, in the mid-1950s. Consistent with the Protocol, in January 2015 an internationally coordinated team undertook the eradication of the grass. Immediately prior to removal of P. pratensis, factors affecting its establishment, persistence and impacts upon local indigenous species was examined within the international management framework of the Antarctic Treaty System. The underlying soil had a high organic content of 15.5%, which may have contributed to the successful establishment of P. pratensis and restricted, at least initially, its vegetative growth to the enriched area. Examination of P. pratensis expansion from the original introduction sites showed that the plant colony intricate root system facilitated little or no coexistence of other native plants within its extent. The non-native plant colony also constituted a novel habitat for soil fauna within Antarctic terrestrial environments. The P. pratensis plant colony provided an unfavorable habitat for two of the locally endemic soil invertebrates, Cryptopygus antarcticus and Belgica antarctica. These observations led to the selection of an appropriate eradication approach, where the plants were targeted for physical extraction along with all underlying soil. During the eradication, c. 500 kg of soil and plant material from the P. pratensis colony was removed from the site. Monitoring one year later showed no evidence of re-establishment. Consistent with the Committee for Environmental Protection ‘Non-native Species Manual’, we recommend development and implementation of rapid response protocols following the discovery of a non-native plant colony to limit future impacts on indigenous species and local habitats.  相似文献   
184.
为了探究呼和浩特白塔国际机场2006-2010年间鸟类组成、数量、多样性等方面的变化及其原因,于2010年11月至2011年10月期间,用样带法对机场飞行区内的鸟类进行了系统调查.将记录的数据与2004年11月至2005年10月间数据进行对比分析.结果表明,第1次调查共记录到鸟类12目25科78种;第2次调查记录到鸟类10目16科31种,其中有11种鸟在第1次调查中没有发现.第1次调查中各季节及全年鸟类的种类、数量、多样性指数均大于第2次;机场鸟类的生态类群、食性变化明显;机场环境的改变是造成2次调查结果差异的根本原因,管理部门改造后的机场环境更加不适合鸟类栖息.根据调查资料提出了鸟击防范对策及建议,以达到持久高效预防鸟击事件的目的.  相似文献   
185.
Trends in Ecosystem Service Research: Early Steps and Current Drivers   总被引:3,自引:0,他引:3  
Over the past 50 years, human beings have influenced ecosystems more rapidly than at any similar time in human history, drastically altering ecosystem functioning. Along with ecosystem transformation and degradation, a number of studies have addressed the functioning, assessment and management of ecosystems. The concept of ecosystem services has been developed in the scientific literature since the end of the 1970s. However, ecosystem service research has focused on certain service categories, ecosystem types, and geographical areas, while substantial knowledge gaps remain concerning several aspects. We assess the development and current status of ecosystem service research on the basis of publications collected from the Web of Science. The material consists of (1) articles (n = 353) from all the years included in the Web of Science down to the completion of the Millennium Ecosystem Assessment and (2) more recent articles (n = 687) published between 2006 and 2008. We also assess the importance of international processes, such as the Convention on Biological Diversity, the Kyoto Protocol and the Millennium Ecosystem Assessment, as drivers of ecosystem service research. Finally, we identify future prospects and research needs concerning the assessment and management of ecosystem services.  相似文献   
186.
对我国"十三五"时期环境保护国际合作形势进行了研判,分析了将面临的机遇和挑战,并提出了环境保护国际合作的对策和建议,以期为做好新时期的环境保护国际合作工作提供参考。  相似文献   
187.
Finland is a forested country with a large export oriented forest industry. In addition to domestic forest extraction, roundwood is imported, thus displacing the environmental impacts of harvests. In this paper, we analyse the international carbon flows of forest industries in Finland from a consumption-based perspective. Quantitative analyses are available on trade embedded emissions of CO2 from fossil fuel combustion, and here we address in a similar way the impact of trade on the carbon budget of the forest products sector in Finland. Carbon flows through the forest industry system increased substantially between 1991 and 2005. We show that the annual carbon balance related to forests and forest industry system in Finland functioned as a sink in 1991, whereas in 2005 the system was a sink on a national level, but not on a global level. Through calculating the carbon content in traded forest industry products and emissions embodied in forest industry activities, we further show that the direct impacts of the forest industry in Finland are only a minor fraction of the total CO2 emissions related to Finnish production. Nearly all of the emissions were caused due to production of exports. Yet, direct carbon dioxide emissions of the industrial production are reported to Finland in the production based inventories.  相似文献   
188.
与发达国家及世界平均水平相比,我国的能源利用效率一直不高。通过对目前发展较快的新兴经济体和发达经济体的能耗指标和温室气体排放指标的国际比较,判断了我国能源效率的水平与节能潜力,分析了我国能耗高污染重的原因,明确了改善方向。  相似文献   
189.
What are the processes that shape implementation of multilateral environmental agreements (MEAs) in multilevel governance? In an attempt to address this question, we move from a top-down view of implementation as compliance with international rules to viewing it as a dynamic process shaped by action at various levels. The Ramsar Convention on Wetlands offers an important context to understand the mechanisms that shape multilevel implementation outcomes. We examine Ramsar Convention implementation in Austria, Mexico, and the Republic of Korea in order to identify relevant processes that define multilevel implementation. These cases represent three different types of government, and shed light on the ways in which international law is implemented by respective governments. The Austrian case, a federal government, illustrates the ways in which subnational authorities (the provinces) are influenced by binding regional institutions (EU-rules) to create a more robust context for protection in terms of designation of Ramsar sites. The Mexican case, a semi-federal government, shows how spurred involvement by local NGOs, states, and scientists can result in significant expansion of efforts. The Korean case, a unitary government, demonstrates the ways in which aligning institutional interests (in this case local governments with national ministries) can lead to strong implementation. Analysis of these cases provides two robust findings and one deserving additional study. First, overlapping governance efforts where activity has ties with multiple regional and international biodiversity efforts tend to see cumulative implementation. Second, institutional and organizational complexity can provide opportunities for local actors to drive the implementation agenda through a mix of processes of coordination and contentious politics. A third, more tentative finding, is that multilevel funding sources can ease implementation.  相似文献   
190.
根据收集到的首都国际机场飞行区活动水平数据,采用适合估算各类移动源污染物排放量的方法和排放因子,建立了2013年首都国际机场移动源排放清单。结果表明,首都国际机场2013年移动源NO_x、CO、HC、SO2和PM_(2.5)排放总量为6 287.1 t、3 596.1 t、364.2t、373.4 t和185.0 t,分别占北京市各污染物总体排放的3.4%、0.3%、0.1%、0.4%和0.2%。其中非道路移动源是各污染物排放的最大贡献源,NO_x、CO、HC、SO2和PM_(2.5)排放量的90.7%、86.7%、79.4%、97.4%和81.3%来源于飞机,中型窄体客机及大型宽体客机贡献突出。相较而言,道路移动源排放比例较低,对HC、CO、PM_(2.5)和NO_x各污染物的贡献率为9.1%、8.6%、6.7%和4.4%。通过标准LTO循环方法估算飞机逐月排放,对LTO循环次数与各污染物排放量进行拟合,发现飞机排放的HC、CO、NO_x、SO2和LTO循环次数之间呈现较为明显的正相关关系,从而提出一种本地化的基于LTO循环次数估算飞机污染气体排放量的简单方法。此外,减少滑行时间可有效降低飞机在LTO循环过程中的污染物排放。  相似文献   
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