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281.
As cities increasingly engage in climate adaptation planning, many are seeking to promote public participation and facilitate the engagement of different civil society actors. Still, the variations that exist among participatory approaches and the merits and tradeoffs associated with each are not well understood. This article examines the experiences of Quito (Ecuador) and Surat (India) to assess how civil society actors contribute to adaptation planning and implementation. The results showcase two distinct approaches to public engagement. The first emphasizes participation of experts, affected communities, and a wide array of citizens to sustain broadly inclusive programmes that incorporate local needs and concerns into adaptation processes and outcomes. The second approach focuses on building targeted partnerships between key government, private, and civil society actors to institutionalize robust decision-making structures, enhance abilities to raise funds, and increase means to directly engage with local community and international actors. A critical analysis of these approaches suggests more inclusive planning processes correspond to higher climate equity and justice outcomes in the short term, but the results also indicate that an emphasis on building dedicated multi-sector governance institutions may enhance long-term programme stability, while ensuring that diverse civil society actors have an ongoing voice in climate adaptation planning and implementation.

Policy relevance

Many local governments in the Global South experience severe capacity and resource constraints. Cities are often required to devolve large-scale planning and decision-making responsibilities, such as those critical to climate adaptation, to different civil society actors. As a result, there needs to be more rigorous assessments of how civil society participation contributes to the adaptation policy and planning process and what local social, political, and economic factors dictate the way cities select different approaches to public engagement. Also, since social equity and justice are key indicators for determining the effectiveness and sustainability of adaptation interventions, urban adaptation plans and policies must also be designed according to local institutional strengths and civic capacities in order to account for the needs of the poor and most vulnerable. Inclusivity, therefore, is critical for ensuring equitable planning processes and just adaptation outcomes.  相似文献   

282.
Developing countries face a difficult challenge in meeting the growing demands for food, water, and energy, which is further compounded by climate change. Effective adaptation to change requires the efficient use of land, water, energy, and other vital resources, and coordinated efforts to minimize trade-offs and maximize synergies. However, as in many developing countries, the policy process in South Asia generally follows a sectoral approach that does not take into account the interconnections and interdependence among the three sectors. Although the concept of a water–energy–food nexus is gaining currency, and adaptation to climate change has become an urgent need, little effort has been made so far to understand the linkages between the nexus perspective and adaptation to climate change. Using the Hindu Kush Himalayan region as an example, this article seeks to increase understanding of the interlinkages in the water, energy, and food nexus, explains why it is important to consider this nexus in the context of adaptation responses, and argues that focusing on trade-offs and synergies using a nexus approach could facilitate greater climate change adaptation and help ensure food, water, and energy security by enhancing resource use efficiency and encouraging greater policy coherence. It concludes that a nexus-based adaption approach – which integrates a nexus perspective into climate change adaptation plans and an adaptation perspective into development plans – is crucial for effective adaptation. The article provides a conceptual framework for considering the nexus approach in relation to climate change adaptation, discusses the potential synergies, trade-offs, and offers a broader framework for making adaptation responses more effective.

Policy relevance

This article draws attention to the importance of the interlinkages in the water, energy, and food nexus, and the implications for sustainable development and adaptation. The potential synergies and complementarities among the sectors should be used to guide formulation of effective adaptation options. The issues highlight the need for a shift in policy approaches from a sectoral focus, which can result in competing and counterproductive actions, to an integrated approach with policy coherence among the sectors that uses knowledge of the interlinkages to maximize gain, optimize trade-offs, and avoid negative impacts.  相似文献   

283.
三种北极微藻对不同温度的适应性研究   总被引:2,自引:0,他引:2       下载免费PDF全文
为了研究北极微藻对不同环境温度的适应性,对分离自北极王湾地区的三种微藻-玛氏骨条藻(Skeletonema marinoi)、小球藻(Chlorella sp.)和衣藻(Chlamydomonas sp.)在不同温度条件下(0℃、4℃和8℃)的生长曲线和抗氧化酶系统进行了测定.结果表明微藻对温度的适应性因种而异:玛氏骨条藻在4℃具有最快生长速率,最高的超氧化物歧化酶(SOD)和过氧化氢酶(CAT)酶活性,及最低的丙二醛(MDA)含量;小球藻的最快生长速率及酶活均在8℃时,MDA含量最低值出现在0℃;衣藻生长情况相差不大,MDA含量的最低值出现在8℃.抗氧化酶系统变化规律也因藻种及温度而异--在0℃与4℃变化时,玛氏骨条藻抗氧化酶系统的三个指标的差异极显著(P<0.01);在0℃与8℃变化时,玛氏骨条藻与小球藻的SOD活性的差异显著(P<0.05),其余两个指标差异不显著;衣藻在三个温度下的三个指标差异均不显著.总体而言,三种藻对三个温度的适应性均较好:其MDA的含量均较低,三种藻各自具有独特的生理代谢机制来适应不同的温度环境.  相似文献   
284.
基于余弦函数的自适应单频干扰消除   总被引:3,自引:1,他引:2       下载免费PDF全文
在野外地震数据采集过程中,如果地震测线上空有高压输电线通过时,在地震记录中就存在一个50HZ左右强单频干扰.这种干扰在地震记录的整个时间段上具有很强的能量,并且从浅层到深层频率、相位和振幅可能不相同,但是它们的变化不太大,可以认为基本保持不变.采用频率域压制方法很难完全消除这种干扰,仅仅是噪声和信号同时压制一定的倍数,因此并没有改善单频分量频率附近的信噪比.我们提出了基于余弦函数的自适应单频干扰消除方法,以有效消除地震数据单频干扰.在时间域内采用频率、时延和振幅的余弦函数来逼近这种单频干扰并从地震记录中减去,以实现消除这种单频干扰的目的.单频干扰余弦函数的振幅使用公式直接计算,单频干扰频率和时延采用自适应方法估算.本方法的最大优点就是能够有效消除干扰,而并不伤害干扰附近有效信号,因此在单频干扰频率分量附近数据信噪比提高了.通过实际数据的试算,说明了本方法的有效性和可行性.  相似文献   
285.
气候变化对中国水资源影响的适应性评估与管理框架   总被引:1,自引:0,他引:1  
通过论述气候变化对中国水资源影响的适应性评估与管理框架,提出一个气候变化影响决策评估工具,它包括:未来气候变化对中国水资源潜在影响的定性描述分析、半定量与定量分析以及适应性对策评估。由于不同气候区域所面临的水资源问题不同,选择中国4个典型案例区域,并确定不同的目标进行气候变化适应性管理综合研究,提出了甄别气候变化影响和适应性管理的新的思路、框架与方法论。该项研究为应对未来气候变化影响的水资源规划与风险管理提供了途径与方法。  相似文献   
286.
气候变化影响与适应研究中的若干问题   总被引:9,自引:1,他引:8  
{{@ convertAbstractHtml(article.abstractinfoCn, "cn")}}   {{if article.graphicalAbstractinfoCn && article.graphicalAbstractinfoCn != ""}}{{@ article.graphicalAbstractinfoCn}}{{/if}}  相似文献   
287.
噪声的分布层次分析及其自适应滤波算法   总被引:5,自引:0,他引:5  
冯桂  张继贤 《测绘科学》2000,25(3):34-36,59
基于对噪声模型的分析 ,提出了两种自适应中值滤波器算法 :(1)对于消除噪声密度较大的脉冲干扰 ,提出了基于剩余脉冲检测的自适应中值滤波器算法 (AMF1) ,通过对滤波器输出是否存在剩余噪声的检测来决定采用的滤波器窗口尺寸 ,从而有效滤除脉冲干扰 ;(2 )对于消除的一定宽度的脉冲干扰 ,则提出了基于脉冲宽度检测的自适应中值滤波器算法 (AMF2 ) ,通过决定干扰脉冲的宽度来确定滤波器窗口的大小 ,从而有效去除较宽的干扰脉冲。通过对实际图像的测试 ,表明提出的算法运算结果优于标准中值滤波器的输出结果  相似文献   
288.
利用热力适应理论讨论了印度洋海温异常影响中国天气和西太平洋副热带高压异常的物理机制。结果表明 :通过第一级热力适应 ,印度洋上的海温异常形成低层气旋式环流 ,并在其东侧的偏南气流中产生对流性降水 ;然后通过第二级热力适应 ,在 50 0 h Pa上导致西太平洋副热带高压加强西伸、2 0 0 h Pa上南亚高压异常增强。从而证明两级热力适应是导致印度洋海温异常影响中国天气气候异常的重要物理机制。  相似文献   
289.
In order to assess the adaptation to metals previously observed in the bioindicator organism, Macoma balthica, subjected to chronic contamination by silver and mercury in the French Loire estuary, the bioaccumulation potential of individual organisms originating from the contaminated Loire estuary and a relatively uncontaminated control estuary (Somme) was evaluated using both radiotracers and stable isotopes of Ag (80 μg Ag litre−1) and Hg (100 μg Hg litre−1). Clams from the contaminated estuary were more sensitive to Ag (LT50 = 9d) than those originating from the Somme estuary (LT50 > 15d), even though the former bioaccumulated Ag to a significantly lower degree. This is attributed to a consequence of the chronic stress induced by Ag while clams were living in their natural environment. Therefore, past history of trace metal contamination should be considered when evaluating the susceptibility of M. balthica to heavy metal exposure. Lower uptake rates obtained for Hg (during the initial uptake phase only) and for Ag in clams from the polluted estuary suggest the presence of an adaptive trait for survival in contaminated areas. However, the lower degree of bioconcentration observed for Ag was not sufficiently low to reduce the sensitivity of the organisms to Ag and allow them to resist the toxic stress. Clams that survived Ag or Hg exposure at LT50 did not protect themselves against metal toxicity by accumulating a significantly lesser amount of these metals than clams which did not survive metal stress. The results suggest that the bioaccumulation potential of each individual was not a factor which can explain the survival ability of M. balthica exposed to chronic Ag and Hg contamination in estuaries. In this case, cellular, biochemical and genetic levels of adaptation are presumed to be of greater importance.  相似文献   
290.
淡水蓝藻的高温适应   总被引:14,自引:0,他引:14  
郑维发  曾昭琪 《湖泊科学》1994,6(4):356-363
本文在有关文献的基础上综合分析了淡水蓝藻对高温的适应,并对淡水蓝藻高温适应机制提出了几种看法。生长在高温中的淡水蓝藻有这样一些特点:(1)不同种类对高温的适应机制稍有不同;(2)类囊体膜具有较高的稳定性;(3)藻体在受热时产生热休克蛋白以保护细胞内的酶免于热变性;(4)光合作用系统具有热稳定性;(5)DNA具有热稳定性;(6)蛋白质的合成系统具有热稳定性。其中DNA和光合作用系统的热稳定性起着关键的作用,热休克蛋白的产生和类囊体膜中脂肪酸的饱和程度是在基因水平上调控的。  相似文献   
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