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1.
Ecological responses to recent climate change   总被引:128,自引:0,他引:128  
There is now ample evidence of the ecological impacts of recent climate change, from polar terrestrial to tropical marine environments. The responses of both flora and fauna span an array of ecosystems and organizational hierarchies, from the species to the community levels. Despite continued uncertainty as to community and ecosystem trajectories under global change, our review exposes a coherent pattern of ecological change across systems. Although we are only at an early stage in the projected trends of global warming, ecological responses to recent climate change are already clearly visible.  相似文献   

2.
由于具有特殊的形态和生理特征,苔藓植物对环境污染和气候变化的反应十分敏感。本文从生态、生理和生长特征等方面综述了苔藓植物对气候变化的响应特征,以期促进苔藓植物对气候变化的响应研究。  相似文献   

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Warming experiments are increasingly relied on to estimate plant responses to global climate change. For experiments to provide meaningful predictions of future responses, they should reflect the empirical record of responses to temperature variability and recent warming, including advances in the timing of flowering and leafing. We compared phenology (the timing of recurring life history events) in observational studies and warming experiments spanning four continents and 1,634 plant species using a common measure of temperature sensitivity (change in days per degree Celsius). We show that warming experiments underpredict advances in the timing of flowering and leafing by 8.5-fold and 4.0-fold, respectively, compared with long-term observations. For species that were common to both study types, the experimental results did not match the observational data in sign or magnitude. The observational data also showed that species that flower earliest in the spring have the highest temperature sensitivities, but this trend was not reflected in the experimental data. These significant mismatches seem to be unrelated to the study length or to the degree of manipulated warming in experiments. The discrepancy between experiments and observations, however, could arise from complex interactions among multiple drivers in the observational data, or it could arise from remediable artefacts in the experiments that result in lower irradiance and drier soils, thus dampening the phenological responses to manipulated warming. Our results introduce uncertainty into ecosystem models that are informed solely by experiments and suggest that responses to climate change that are predicted using such models should be re-evaluated.  相似文献   

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选取了温暖指数、寒冷指数、湿润指数、1月最低温度、7月最高温度和年降水量等气候变量为因子,使用地理信息系统和Logistic回归模型的结合,模拟中国北方森林的潜在分布区及其对气候变化的响应.用敏感性、指定度和总正确率评价预测的精度,4种北方森林的敏感性为81%~92%,指定度为82%~92%,总正确率82%~92%.结果表明:在未来气候条件(2071-2100)下,中国北方森林的分布区将发生大范围的转移;常绿针叶林的面积扩大15.2%,阔叶落叶林、落叶针叶林和针阔混交林的面积分别减小86.7%,71.7%,32.1%.  相似文献   

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Linking climate change to lemming cycles   总被引:2,自引:0,他引:2  
The population cycles of rodents at northern latitudes have puzzled people for centuries, and their impact is manifest throughout the alpine ecosystem. Climate change is known to be able to drive animal population dynamics between stable and cyclic phases, and has been suggested to cause the recent changes in cyclic dynamics of rodents and their predators. But although predator-rodent interactions are commonly argued to be the cause of the Fennoscandian rodent cycles, the role of the environment in the modulation of such dynamics is often poorly understood in natural systems. Hence, quantitative links between climate-driven processes and rodent dynamics have so far been lacking. Here we show that winter weather and snow conditions, together with density dependence in the net population growth rate, account for the observed population dynamics of the rodent community dominated by lemmings (Lemmus lemmus) in an alpine Norwegian core habitat between 1970 and 1997, and predict the observed absence of rodent peak years after 1994. These local rodent dynamics are coherent with alpine bird dynamics both locally and over all of southern Norway, consistent with the influence of large-scale fluctuations in winter conditions. The relationship between commonly available meteorological data and snow conditions indicates that changes in temperature and humidity, and thus conditions in the subnivean space, seem to markedly affect the dynamics of alpine rodents and their linked groups. The pattern of less regular rodent peaks, and corresponding changes in the overall dynamics of the alpine ecosystem, thus seems likely to prevail over a growing area under projected climate change.  相似文献   

9.
Thomas CD  Williamson M 《Nature》2012,482(7386):E4-5; author reply E5-6
Arising from F. He & S. P. Hubbell 473, 368-371 (2011). Statistical relationships between habitat area and the number of species observed (species-area relationships, SARs) are sometimes used to assess extinction risks following habitat destruction or loss of climatic suitability. He and Hubbell argue that the numbers of species confined to-rather than observed in-different areas (endemics-area relationships, EARs) should be used instead of SARs, and that SAR-based extinction estimates in the literature are too high. We suggest that He and Hubbell's SAR estimates are biased, that the empirical data they use are not appropriate to calculate extinction risks, and that their statements about extinction risks from climate change do not take into account non-SAR-based estimates or recent observations. Species have already responded to climate change in a manner consistent with high future extinction risks.  相似文献   

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【目的】随气候变化加剧,未来西南地区针叶林分布存在诸多不确定性,进行未来气候下西南地区常见针叶树种适宜分布区研究,为该地区森林生态安全评估提供参考。【方法】基于最大熵模型(MaxEnt)模拟未来气候情景下西南地区常见的12种针叶树的气候适宜分布区。【结果】MaxEnt模型能够很好地模拟西南地区12个树种的潜在分布,AUC值均达0.9以上; 2070年MPI-ESM-LR模式RCP4.5情景下西南地区12种常见针叶树种气候适宜区面积分布变化显著,包括冷杉、三尖杉、杉木、干香柏、柏木、水杉、云南松、红豆杉和福建柏在内的9个树种气候适宜区与气候最适区面积增加11.1%~412.8%;银杉和油麦吊云杉的气候适宜区面积分别增加6.0%和32.8%,但气候最适区面积减少了0.8%和3.5%;云南油杉未来气候适宜区和气候最适区的面积则减少24.0%和29.1%。【结论】西南地区针叶林中广布树种的气候适宜区面积会得益于气候变化而扩大,但云南油杉和油麦吊云杉等一些西南特有乡土树种的气候适宜区面积则会因为气候变化而缩小,因此对特有乡土树种的保护应给予重视。  相似文献   

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回顾了2022年全球气候变化与治理领域取得的系列令人瞩目的成果。介绍了2022年全球温度持续升高、温室气体浓度创新高、海冰范围缩小及海平面上升等气候变化科学共识;“三重”拉尼娜重现、南亚高温洪水、欧洲及中国高温干旱等极端天气气候事件;全球碳减排承诺、多灾种预警系统、IPCC第六次评估报告(AR6)、第27届联合国气候变化大会(COP27)、生物多样性大会(COP15)等全球气候变化治理与认知方面的最新进展。  相似文献   

13.
Attributing physical and biological impacts to anthropogenic climate change   总被引:4,自引:0,他引:4  
Significant changes in physical and biological systems are occurring on all continents and in most oceans, with a concentration of available data in Europe and North America. Most of these changes are in the direction expected with warming temperature. Here we show that these changes in natural systems since at least 1970 are occurring in regions of observed temperature increases, and that these temperature increases at continental scales cannot be explained by natural climate variations alone. Given the conclusions from the Intergovernmental Panel on Climate Change (IPCC) Fourth Assessment Report that most of the observed increase in global average temperatures since the mid-twentieth century is very likely to be due to the observed increase in anthropogenic greenhouse gas concentrations, and furthermore that it is likely that there has been significant anthropogenic warming over the past 50 years averaged over each continent except Antarctica, we conclude that anthropogenic climate change is having a significant impact on physical and biological systems globally and in some continents.  相似文献   

14.
Respondence and feedback of modern sand deserts to climate change   总被引:1,自引:0,他引:1  
The research on the respondence and feedback of modern sand deserts to the climate change is an important component part in the studies on the global climate change. Deserts respond to the climate change, meanwhile, they affect the climate with their feedback of peculiar environment during the respondence. Many researches on desert climate have been carried out at home and abroad. However, there is little research on the respondence and feedback of modern fixed, semi-fixed and mobile deserts in arid areas to the climate change, in which the factor analysis as well as the parameter changing effects is especially the difficult problem all along. In this note, the parameters of the respondence and feedback of Gurbantunggut Desert to the climate change are measured and analyzed, some variable parameters of water-heat exchange are obtained, and a numerical model of desertification is developed according to a series of climate change of about 40 years and the variable relations of meteorological and physical features of the sand surface in Gurbantunggut Desert.  相似文献   

15.
Emperor penguins and climate change   总被引:15,自引:0,他引:15  
Barbraud C  Weimerskirch H 《Nature》2001,411(6834):183-186
Variations in ocean-atmosphere coupling over time in the Southern Ocean have dominant effects on sea-ice extent and ecosystem structure, but the ultimate consequences of such environmental changes for large marine predators cannot be accurately predicted because of the absence of long-term data series on key demographic parameters. Here, we use the longest time series available on demographic parameters of an Antarctic large predator breeding on fast ice and relying on food resources from the Southern Ocean. We show that over the past 50 years, the population of emperor penguins (Aptenodytes forsteri) in Terre Adélie has declined by 50% because of a decrease in adult survival during the late 1970s. At this time there was a prolonged abnormally warm period with reduced sea-ice extent. Mortality rates increased when warm sea-surface temperatures occurred in the foraging area and when annual sea-ice extent was reduced, and were higher for males than for females. In contrast with survival, emperor penguins hatched fewer eggs when winter sea-ice was extended. These results indicate strong and contrasting effects of large-scale oceanographic processes and sea-ice extent on the demography of emperor penguins, and their potential high susceptibility to climate change.  相似文献   

16.
Despite decades of research, the roles of climate and humans in driving the dramatic extinctions of large-bodied mammals during the Late Quaternary period remain contentious. Here we use ancient DNA, species distribution models and the human fossil record to elucidate how climate and humans shaped the demographic history of woolly rhinoceros, woolly mammoth, wild horse, reindeer, bison and musk ox. We show that climate has been a major driver of population change over the past 50,000 years. However, each species responds differently to the effects of climatic shifts, habitat redistribution and human encroachment. Although climate change alone can explain the extinction of some species, such as Eurasian musk ox and woolly rhinoceros, a combination of climatic and anthropogenic effects appears to be responsible for the extinction of others, including Eurasian steppe bison and wild horse. We find no genetic signature or any distinctive range dynamics distinguishing extinct from surviving species, emphasizing the challenges associated with predicting future responses of extant mammals to climate and human-mediated habitat change.  相似文献   

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本文围绕气候变化背景下的中国植被物候研究,梳理了植被物候对气候变化的响应机制,分析了中国植被物候变化对陆地生态系统碳、水和能量循环的影响,植被物候变化对局地气候的反馈机制以及通过大气环流对气候系统的影响.主要结论:1)中国植被生长季开始日期提前1~6 d?(10 a)–1,结束日期推迟2~5 d?(10 a)–1,生长季显著延长;2)中国中高纬度地区植被对温度的响应明显高于亚热带和热带地区,温度在控制植被物候的过程中起到多重作用,降水主要影响干旱和半干旱地区的植被物候;3)植被生长季延长增加陆地生态系统生产力,增加中国碳汇;4)植被物候变化改变植被的蒸散发量,从而改变我国的流域尺度河流径流;5)在中国大部分地区,植被物候变化对气候系统产生负反馈作用,甚至影响大气环流过程.中国植被物候的研究越来越多,但仍存在亟待解决的科学问题,比如未来中国植被物候研究需要更加关注遥感数据反演精度,明确物候响应气候变化机制的尺度效应,结合机器学习等智能算法改进物候模型提高物候模拟精度,并重视农作物物候,加强物候与森林管理结合研究以提高我国生态系统碳汇能力,积极面对碳中和带来的机遇与挑战.   相似文献   

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Lisiecki LE  Raymo ME  Curry WB 《Nature》2008,456(7218):85-88
The factors driving glacial changes in ocean overturning circulation are not well understood. On the basis of a comparison of 20 climate variables over the past four glacial cycles, the SPECMAP project proposed that summer insolation at high northern latitudes (that is, Milankovitch forcing) drives the same sequence of ocean circulation and other climate responses over 100-kyr eccentricity cycles, 41-kyr obliquity cycles and 23-kyr precession cycles. SPECMAP analysed the circulation response at only a few sites in the Atlantic Ocean, however, and the phase of circulation response has been shown to vary by site and orbital band. Here we test the SPECMAP hypothesis by measuring the phase of orbital responses in benthic delta(13)C (a proxy indicator of ocean nutrient content) at 24 sites throughout the Atlantic over the past 425 kyr. On the basis of delta(13)C responses at 3,000-4,010 m water depth, we find that maxima in Milankovitch forcing are associated with greater mid-depth overturning in the obliquity band but less overturning in the precession band. This suggests that Atlantic overturning is strongly sensitive to factors beyond ice volume and summer insolation at high northern latitudes. A better understanding of these processes could lead to improvements in model estimates of overturning rates, which range from a 40 per cent increase to a 40 per cent decrease at the Last Glacial Maximum and a 10-50 per cent decrease over the next 140 yr in response to projected increases in atmospheric CO(2) (ref. 4).  相似文献   

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 适应气候变化是现阶段应对气候变化行动的重要举措。适应气候变化技术的识别标准是编制适应气候变化清单的基础, 是适应气候变化方法学的重要组成部分。本研究通过对气候变化及其影响进行分析, 明确人类所面对的气候变化问题的内涵;结合适应技术定义, 确立适应气候变化技术核心识别标准是气候变化问题的针对性, 其关键在于将技术的适应方面与常规方面区分开来。另一方面, 对比分析适应技术与减缓技术, 明确有效区分技术的减缓效果与适应效果是适应气候变化技术识别的重要标准。依托识别标准, 不但可以对不同领域、不同地域已有的适应技术进行识别筛选, 也可为未来适应气候变化技术研发提供指导, 为适应气候变化技术体系构建奠定基础。  相似文献   

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