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1.
用COHERENS模式和数值试验的方法,研究了当渤海气温平均上升1℃和2℃时,渤海海洋微型浮游植物数量和NO3-N浓度的变化,结果发现当气温增加时,渤海微型浮游植物的最大增加和NO3-N浓度的最大减少在3月份,而在6~9月份的夏季,则变化不明显.气温增加1℃时,微型浮游植物有机碳在1~2月份增加了30%,而在6~9月增...  相似文献   

2.
以弧菌为疾病模型代表,综述了气候变化对海洋弧菌疾病的影响,指出温度是其主要影响因素,在此基础上探讨了气候变化对海洋弧菌疾病的影响机制:海水温度升高,弧菌致病因子表达上调,致病性增强;海水温度升高,弧菌分布范围扩大,暴发高峰提前,感染时间延长;海水温度升高,弧菌载体的分布范围扩大,间接影响弧菌的分布范围;海平面升高,海水入侵,内陆水体盐度增加,与之相对应的是气候变化带来更加频繁的降雨,导致河口及滨海湿地的盐分减少,弧菌适宜生存的范围扩大;宿主为应对海水温度升高而进行一系列生理调节,改变宿主对弧菌的易感性。在综述国外相关研究的基础上,提出了该领域今后的几个研究方向,为我国海洋弧菌类疾病的预防与管理提供有价值的参考。  相似文献   

3.
全球气候变化下的中国粮食安全问题研究   总被引:2,自引:2,他引:2  
粮食是人类生存的基础,保障粮食安全是“2030年可持续发展议程”的重要目标之一。论文基于粮食系统视角,从全球气候变化对粮食系统的作用、保障粮食安全对全球气候变化的影响,以及应对全球气候变化的粮食安全适应性策略出发,揭示粮食安全与全球气候变化的相互作用,系统梳理全球气候变化下的中国粮食安全问题。研究结果表明:1)全球气候变化导致粮食系统不确定性增加,且对中国粮食生产的影响加剧;2)粮食需求是全球气候变化的主要驱动力,粮食生产要素的重新配置加剧了全球气候变化;3)多尺度有机结合应对全球气候变化保障粮食安全需在微观上“藏粮于技”实现提质增效,在中观上“藏粮于地”注重生态建设,在宏观上坚持市场为主导完善粮食政策体系。全球气候变化背景下,保障粮食安全研究呈现从单一学科、单一维度、单一手段向依靠多学科开展多尺度、多要素、系统综合集成研究保障粮食安全转变,从高碳粮食系统向低碳高效粮食系统转变的趋势。  相似文献   

4.
简要回顾了自1993年以来世界范围内海洋铁施肥试验的研究动态以及阶段性研究成果,注重探讨铁施肥后初级生产力的变化情况,海水中颗粒态有机碳变化与迁移情况以及铁施肥可能造成的环境影响及生态效应,初步分析了海洋铁施肥作为缓解气候变化策略面临的主要问题,以及进一步开展海洋铁施肥研究需要解决的关键问题,为我国开展海洋铁施肥相关的...  相似文献   

5.
短期海洋酸化对黄海近岸浮游植物群落结构的影响   总被引:1,自引:0,他引:1  
为探讨短期海洋酸化对黄海近岸水域浮游植物群落结构的影响,本文在荣成湾海域采用大体积培养实验的方法进行了研究。控制组通入过滤自然空气,CO2组通入含1000 ppm(Parts per million,百万分之一) CO2的过滤混合空气。结果表明,CO2浓度升高引起的海洋酸化显著促进了黄海近岸海域Chl a浓度和浮游植物总丰度的上升,同时浮游植物种类数在高CO2浓度条件下出现明显下降。不同种类的浮游植物对CO2浓度升高的响应有所不同,培养过程中CO2组菱形藻(Nitzschia spp.)和斯氏几内亚藻(Guinardia striata)丰度比控制组出现明显上升,海链藻(Thalassiosira spp.)和中肋骨条藻(Skeletonema costatum)丰度在CO2组和控制组并未呈现出明显差异。CO2浓度升高条件下较大粒径浮游植物相比较小粒径浮游植物生长更快。海洋酸化显著改变了黄海近岸水域的浮游植物群落结构,这可能对海洋生态系统产生影响。  相似文献   

6.
7.
全球气候变化对森林生态系统的影响   总被引:52,自引:1,他引:52  
人类活动所引起的温室效应及由此造成的全球气候变化和对全球生态环境的影响正越来越引起人们的关注。作为全球陆地生态系统一个重要组分的森林对未来气候变化的响应更是人们关注的重点。文中系统地论述了未来气候变化对森林生态系统树种组成、林分结构、分布和生产力的潜在响应,提出了今后需要加强的一些研究领域。  相似文献   

8.
近几十年以来全球正在经历以全球变暖为突出标志的气候变化。《联合国气候变化框架公约》和《京都议定书》的签订是全球气候变化的里程碑。全球温室气体规制形成及其后续谈判的过程可以看出,全球气候变化问题的日益突出导致了全球温室气体国际规制的逐步趋严。随着温室气体国际规制的趋严,温室气体的排放权不再是一项免费的公共资源。这已经成为具有全球共识的大趋势,也是全球经济发展中的一个重大新变量,将对全球各国自身的温室气体规制和经济发展产生深远的影响。2015年是全球气候变化谈判的关键一年,各方为取得谈判成功正在加大协调和准备的努力。  相似文献   

9.
海洋浮游植物是全球初级生产力的重要贡献者,它们的生物量主要受到氮、磷、铁等营养元素的限制。磷元素作为浮游植物所必需的元素,在寡营养海域的真光层海水中十分缺乏,是浮游植物生长的限制因子。磷元素的缺乏不仅直接影响浮游植物的生长繁殖及物种演替,还对海洋碳、氮生物地球化学循环产生深远影响。全球变暖加剧海水层化,进而减少垂直混合带来的营养盐补充。面对不断变化的海洋环境,浮游植物通过减缓细胞生长、加强磷吸收和储存、分解有机磷、磷脂替代、降低细胞对磷酸盐的依赖等方式,应对海洋环境中的磷限制。本文总结了近年来海洋浮游植物应对磷限制响应机制的最新研究进展,主要从生理响应和生态效应方面综述了海洋磷限制对浮游植物的影响以及浮游植物响应海洋磷限制的策略,希望对海洋浮游植物和海洋环境科学相关研究具有借鉴意义。  相似文献   

10.
<正>据英国《卫报》近日报道,美国国家海洋和大气管理局最新公布的上层海洋(0~2000m)热含量曲线图显示,2014年全球海洋继续变暖.人类活动引发了气候变化,但是仍有许多人否认这一事实,且他们宣称2014年并不会是太热的一年.但是近期一系列地表气温报告却给了他们当头一棒——2014的平均气温已创历史记录.  相似文献   

11.
IntroductionGlobalclimatemodelspredicttemperatureincreasesduetoenhancedgreenhousewarminginthenot too distantfuture (Houghton ,1990 ) .Ithasbeenarguedthatoneoftheimportanteffectsofglobalwarmingwillbetoacceleratethedecompositionofsoilorganicmatter,therebyrele…  相似文献   

12.
Simulating global soil-CO2 flux and its response to climate change   总被引:14,自引:4,他引:14  
It has been argued that increased soil respiration would become a major atmospheric source of CO2 in the event of global warming. The simple statistical models were developed based on a georeferenced database with 0.5° × 0.5° longitude/latitude resolution to simulate global soil-CO2 fluxes, to investigate climatic effects on these fluxes using sensitivity experiments, and to assess possible responses of soil-CO2 fluxes to various climate change scenarios. The statistical models yield a value of 69 PgC/a of global soil CO2 fluxes for current condition. Sensitivity experiments confirm that the fluxes are responsive to changes in temperature,precipitation and actual evapotranspiration, but increases in temperature and actual evapotranspiration affect soil-CO2 fluxes more than increases in precipitation. Using climatic change projections from four global circulation models, each corresponding to an equilibrium doubling of CO2, it can be found that the largest increases in soil-CO2 fluxes were associated with the boreal and tundra regions. The globally averaged soil-CO2 fluxes were estimated to increase by about 35 % above current values, providing a positive feedback to the greenhouse effect.  相似文献   

13.
亚洲季风变迁与全球气候的联系   总被引:1,自引:0,他引:1       下载免费PDF全文
通过研究冰期-间冰期至百年尺度亚洲季风的演变特征,阐明了季风变化同南北半球冰量、太阳辐射、大洋环流、热带辐合带等气候系统内外部因子的动力联系。在海-陆-气相互作用的框架下提出了"冰期-间冰期印度季风变化动力学"新理论,揭示大西洋经向环流对东亚季风突变事件的影响和动力过程,探讨了全新世亚洲季风变化的时空特征和控制因素。该项成果以亚洲季风变迁历史和机理为主线,从地球系统科学的视角,将亚洲古季风研究拓展为多尺度与多动力因子、区域与全球相结合的集成研究,推动了与季风相关的过去全球变化科学的发展。  相似文献   

14.
气候变化和土壤侵蚀是当前全球变化研究重点关注的两个自然过程,二者之间的相互作用是地表过程的重要研究内容之一。本文从土壤侵蚀对气候变化的响应、碳循环过程对土壤侵蚀的反馈两个方面综述了气候变化与土壤侵蚀相互作用研究进展。分析认为:理想的地质载体是深刻理解地质历史时期土壤侵蚀对气候变化响应特征的关键;土壤侵蚀预测模型的适用条件和范围以及降雨侵蚀力估算方法缺乏标准化是造成土壤侵蚀量估算结果存在差异的主要因素;侵蚀作用下土壤有机碳矿化的生物学过程与机制是科学评估土壤侵蚀是碳源或碳汇的关键环节。建议未来在以下三个方向开展工作:(1)以湖泊沉积物为地质载体研究历史时期气候变化与土壤侵蚀有着巨大发展和应用潜力,建议利用AMS 14C、137Cs和210Pb等多种定年手段,使用环境指示意义明确的代用指标,建立近千年高分辨率流域气候与侵蚀序列,研究十年至百年尺度气候变化与土壤侵蚀之间的关系;(2)流域版水蚀预报模型(WEPP)可能更适合小流域预测研究,在其实践应用过程中除规范标准小区的坡度和坡长之外,还应通过长期观测和试验确定不同气候区侵蚀性降雨阙值以计算降雨侵蚀力;(3)可以尝试采用定量稳定同位素探针技...  相似文献   

15.
Challenge of global climate change: Prospects for a new energy paradigm   总被引:1,自引:0,他引:1  
Perspectives on the challenge posed by potential future climate change are presented including a discussion of prospects for carbon capture followed either by sequestration or reuse including opportunities for alternatives to the use of oil in the transportation sector. The potential for wind energy as an alternative to fossil fuel energy as a source of electricity is outlined including the related opportunities for cost effective curtailment of future growth in emissions of CO2.  相似文献   

16.
This paper identifies the literature that deals with adaptation to climate change in the transport sector. It presents a systematic review of the adaptations suggested in the literature. Although it is frequently claimed that this socially and economically important sector is particularly vulnerable to climate change, there is comparatively little research into its adaptation. The 63 sources we found are analysed following an action framework of adaptation. This distinguishes different adaptational functions and means of adaptation. By an open coding procedure, a total of 245 adaptations are found and classified. The paper shows a broad diversity of interdependent actors to be relevant—ranging from transportation providers to public and private actors and households. Crucial actors are hybrid in terms of being public or private. A substantial share of the identified adaptations follows a top-down adaptation policy pattern where a public or hybrid operator initiates action that affects private actors. Most of the exceptions from this pattern are technical or engineering measures. Identified adaptations mostly require institutional means, followed by technical means, and knowledge. Generally, knowledge on adapting transport to climate change is still in a stage of infancy. The existing literature either focuses on overly general adaptations, or on detailed technical measures. Further research is needed on the actual implementation of adaptation, and on more precise institutional instruments that fill the gap between too vague and too site-specific adaptations.  相似文献   

17.
Defining response capacity to enhance climate change policy   总被引:1,自引:0,他引:1  
Climate change adaptation and mitigation decisions made by governments are usually taken in different policy domains. At the individual level however, adaptation and mitigation activities are undertaken together as part of the management of risk and resources. We propose that a useful starting point to develop a national climate policy is to understand what societal response might mean in practice. First we frame the set of responses at the national policy level as a trade off between investment in the development and diffusion of new technology, and investment in encouraging and enabling society to change its behaviour and or adopt the new technology. We argue that these are the pertinent trade-offs, rather than those usually posited between climate change mitigation and adaptation. The preference for a policy response that focuses more on technological innovation rather than one that focuses on changing social behaviour will be influenced by the capacity of different societies to change their greenhouse gas emissions; by perceived vulnerability to climate impacts; and by capacity to modify social behaviour and physical environment. Starting with this complete vision of response options should enable policy makers to re-evaluate the risk environment and the set of response options available to them. From here, policy makers should consider who is responsible for making climate response decisions and when actions should be taken. Institutional arrangements dictate social and political acceptability of different policies, they structure worldviews, and they determine the provision of resources for investment in technological innovation and social change. The importance of focussing on the timing of the response is emphasised to maximise the potential for adjustments through social learning and institutional change at different policy scales. We argue that the ability to respond to climate change is both enabled and constrained by social and technological conditions. The ability of society to respond to climate change and the need for technological change for both decarbonisation and for dealing with surprise in general, are central to concepts of sustainable development.  相似文献   

18.
In this study we utilize content analysis techniques to examine how the issue of global warming and climate change has been characterized during the period of 1992 through 2005 by the Houston Chronicle—the largest regional newspaper in the Texas coastal region. A total of 795 global warming and climate change news articles from the Houston Chronicle are collected, coded and analyzed. Data analyses are organized and presented with regard to issue salience, various issue attributes (issue image, scope, linkage, participant, proposed solution and responsible party), use of science, and scientific information sources cited in the news stories. We find that regional media attention to the global climate change issue generally increases over time and an overwhelming majority of the news articles view the issue as a harmful problem. However, given the scientific consensus that global warming will result in significant devastating climate change consequences to the coastal regions, there are still a fair number of news articles delivering mixed, undetermined or even non-harmful messages. We also find that climate change is often discussed as a national or international-global issue, and frequently linked to a number of other public issues rather than just being viewed as an environmental–ecological problem. Moreover, we find that emphasis on issue solutions is placed more on mitigation strategies than on adaptation behaviors, and that both governmental and non-governmental actions and responsibilities are suggested for dealing with climate change. In addition, our findings indicate that the regional newspaper in Texas obtains scientific information on climate change primarily from academic institutions. Implications of our findings and recommendations for future research are discussed in the concluding section.  相似文献   

19.
On integration of policies for climate and global change   总被引:2,自引:0,他引:2  
Currently envisaged mitigation of greenhouse gases (GHG) emissions will be insufficient to appreciably limit climate change and its impacts. Adaptation holds the promise of ameliorating the impacts on a small subset of systems being affected. There is no question that both will be needed. However, climate change is only part of a broader multi-stress setting of global through to local changes. Privileging climate related policies over other concerns leads to tragic outcomes. Climate policies need to be designed for and integrated into this broader and challenging context. This paper focuses on placing climate change within the broader context of global change and the importance of aligning climate policy objectives with the myriad other policies that still need to be implemented if our primary goal is improving human welfare rather than limiting our focus to climate change and its impacts.  相似文献   

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