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411.
Joint implementation (JI) can provide flexibility in meetingKyoto Protocol commitments, and 44 nations have already participated inthe U.N. Framework Convention on Climate Change – Activities Implemented Jointly (AIJ) pilot. Thispaper surveys JI policy and projects in three countries – Russia, Ukraine,and Poland – over the past five years and examines the effects of domesticinstitutions, foreign policy, and investment trends on JI in each country.The institutional and economic situation in the three nations differs greatly,and these distinctions have resulted in very different circumstances for AIJprojects, affecting both their number and scope. Poland has a well-definedset of rules and procedures for JI and its economy is quite strong. Ukrainehas not yet established criteria or clear procedures for AIJ project reviewsalthough it does have an Interagency Commission on Climate Change.Ukraine's economy declined by over 40% in the 1990s. Russia'seconomy has also declined, to a lesser extent. Russia does have aprocedure for reviewing AIJ projects, though it has temporarily halted thesereviews. Countries seeking JI investment can take several steps to improve thenumber and quality of AIJ projects that they receive. In the long term,governments can create macroeconomic stability and a solid legalinvestment basis to attract investment for JI and other areas. In the shortterm, however, governments can undertake several simple and inexpensivesteps to promote JI. Establishing clear rules and procedures for AIJprojects is an important step. So too are clearly delegating responsibilityfor AIJ project review and providing a single JI point of contact in thegovernment to which investors and project developers can turn. Gainingmore experience in implementing AIJ projects now is important preparationfor fully implementing the Kyoto Protocol beginning in 2008.  相似文献   
412.
介绍了我国植被恢复中存在的问题,由此引出天然植被的重要价值:保持水土和营养;防止水灾、旱灾、火灾、暴风雨、虫害;防止污染;防止水土流失和沙漠化;调节地区与全球气候;保护生物多样性以及可再生能源等.在此基础上分析了我国植被恢复的误区:大量使用外来物种;忽略了健康生态系统要求的异质性;忽略了物种之间的相互作用;忽略了农业区的植被恢复;覆盖率常被用作唯一的评估标准;对当地濒危物种的需要缺乏考虑;城市绿化忽略了植被的生态功能.针对这些误区提出了笔者认为符合生态学原理的植被恢复措施.  相似文献   
413.
中国水足迹强度空间关联格局及影响因素分析   总被引:3,自引:3,他引:3  
水资源短缺已成为制约经济社会发展的重要因素,科学审视水资源利用现状、探索水资源可持续发展的有效动力具有重要的理论和现实意义。基于水足迹视角分别测算2006-2015年中国31个省域的水足迹强度,利用探索性空间数据分析(ESDA)对其时空格局演变特征进行解析,考虑到该方法空间描述的粗略性,通过引入时空跃迁测度法进行细化,并借助空间杜宾模型探讨其影响因素。结果表明:中国水足迹强度空间集聚效应显著且具有跃迁性,但主要以类型Ⅵ为主,其空间结构具有一定的路径依赖特征;人口数量仍然是当前中国水足迹强度的一个主要驱动因子,而城镇化率和对外开放程度则对降低水足迹强度起积极作用;中国水足迹强度存在“倒N型”的Kuznets曲线,且大部分省份水足迹强度处于第一个拐点与第二个拐点之间,北京、天津、上海等区域已越过第二个拐点,处于水足迹强度下降阶段,而部分西部欠发达地区仍未跨越第一个拐点。  相似文献   
414.
Analysis on the long term discharge of a catchment   总被引:1,自引:0,他引:1  
IntroductionItiswellknownthatthecharacteristicsofthecatchmentdischargewillchangewithlanduse.Inthispaper,thefocusistodiscussthemodeloflongtermdischargeofcatchmentwhichincludestwokindsoflanduse :oneisforestattheupperpartofthecatchment,anotherispaddyfield…  相似文献   
415.
Matthew Bach 《环境政策》2019,28(1):87-103
ABSTRACT

The oil and gas industry has traditionally been reticent to engage with the issues surrounding climate change, typically being cast as a laggard. Yet, over recent years, the sector has begun taking on a more active role in climate governance, doing so in a variety of capacities – as initiators, catalysts and participants in industry-led or multi-stakeholder efforts. The Oil and Gas Climate Initiative is reviewed, as a case study to illustrate emerging climate leadership within the global oil and gas industry. In 2015, its members committed to a two-degree pathway. The paucity of research on the nascent role of oil and gas firms in climate governance is addressed.  相似文献   
416.
合成了一种用来吸附和去除水溶液中酚类化合物的 2 羧基苯甲酰基修饰的超高交联吸附树脂 (ZH 0 1) ,并从动力学和吸附容量角度比较了XAD 4、AM 1和ZH 0 1分别吸附浓度为 80 0mg/L苯酚的情况。实验结果表明 ,ZH 0 1吸附剂有利于吸附苯酚、对甲苯酚和对硝基苯酚之类的酚类化合物。动力学和热力学研究都得到了相同的结果 :ZH 0 1对苯酚和对甲苯酚吸附是化学吸附的过渡状态 ,而对对硝基苯酚的吸附是一种物理吸附过程 ,并且显示了ZH 0 1表面均孔特性。苯酚在ZH 0 1上的小柱吸附研究表明了吸附穿透容量和总吸附量分别为 2 .38mmol/g和 3.0 5mmol/g ,溶剂甲醇对吸附在ZH 0 1上苯酚的脱附效果较好。  相似文献   
417.
酸性条件下,借助过渡金属的催化氧化性,可以将烟气中的SO_2转化为S(Ⅳ),以Fe~(2 )为能源,在繁殖过程中不断将Fe~(2 )转化为Fe~(3 )的T.f菌(氧化亚铁硫杆菌)引入脱硫吸收液以维持Fe~(3 )浓度,从而获得较高的脱硫效率.对T.f菌的驯化以及微量营养物质的加入,是T.f菌发挥其功效的关键.  相似文献   
418.
ABSTRACT: The Pacific Northwest (PNW) regional assessment is an integrated examination of the consequences of natural climate variability and projected future climate change for the natural and human systems of the region. The assessment currently focuses on four sectors: hydrology/water resources, forests and forestry, aquatic ecosystems, and coastal activities. The assessment begins by identifying and elucidating the natural patterns of climate vanability in the PNW on interannual to decadal timescales. The pathways through which these climate variations are manifested and the resultant impacts on the natural and human systems of the region are investigated. Knowledge of these pathways allows an analysis of the potential impacts of future climate change, as defined by IPCC climate change scenarios. In this paper, we examine the sensitivity, adaptability and vulnerability of hydrology and water resources to climate variability and change. We focus on the Columbia River Basin, which covers approximately 75 percent of the PNW and is the basis for the dominant water resources system of the PNW. The water resources system of the Columbia River is sensitive to climate variability, especially with respect to drought. Management inertia and the lack of a centralized authority coordinating all uses of the resource impede adaptability to drought and optimization of water distribution. Climate change projections suggest exacerbated conditions of conflict between users as a result of low summertime streamfiow conditions. An understanding of the patterns and consequences of regional climate variability is crucial to developing an adequate response to future changes in climate.  相似文献   
419.
湿地被喻为“地球之肾”,因其蕴藏着极其丰富的生物资源,同时又具有汇聚、平衡水分、分配二氧化碳的功能.为充分发挥龙湖湿地的资源优势和旅游潜力,实现区域经济和生态环境保护的双赢,通过实地抽样调查、数据归类分析等方法,初步探讨了龙湖湿地的资源优势和面临的生态环境问题.建议从调控城市湿地生态系统与周边陆域生态系统的耦合关系入手,运用强化湿地管理、加大科技投入、提高群众保护意识等手段,构建一个和谐的生态环境.  相似文献   
420.
Wind is one of the fastest growing renewable energy resources in the electric power system. Availability of wind energy is volatile in nature due to the stochastic behavior of wind speed and non-linear variation of the wind power curve of wind turbine generator. Because of this impression and uncertainty, the availability estimation of wind power has become a challenging issue. In this paper, Markov Fuzzy Reward technique has been proposed for finding out the reliability of wind farm by assessing the availability of wind power. According to this technique, availability of the wind power has been estimated considering wind farm and demand both as a multi-state system. In addition to the availability, different reliability indices such as the number of absolute failures, mean time to deficiency, and probability of failures of a wind farm have been assessed in a time horizon, which can provide useful information for the power system planner at wind farm installing stage. A comparison of this study reveals the efficacy of the proposed Markov Fuzzy Reward approach over the conventional Markov Reward approach.  相似文献   
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