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1.
Climate change and population declines in a long-distance migratory bird   总被引:1,自引:0,他引:1  
Both C  Bouwhuis S  Lessells CM  Visser ME 《Nature》2006,441(7089):81-83
Phenological responses to climate change differ across trophic levels, which may lead to birds failing to breed at the time of maximal food abundance. Here we investigate the population consequences of such mistiming in the migratory pied flycatcher, Ficedula hypoleuca. In a comparison of nine Dutch populations, we find that populations have declined by about 90% over the past two decades in areas where the food for provisioning nestlings peaks early in the season and the birds are currently mistimed. In areas with a late food peak, early-breeding birds still breed at the right time, and there is, at most, a weak population decline. If food phenology advances further, we also predict population declines in areas with a late food peak, as in these areas adjustment to an advanced food peak is insufficient. Mistiming as a result of climate change is probably a widespread phenomenon, and here we provide evidence that it can lead to population declines.  相似文献   

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3.
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   

4.
Accompanying with the economic development and the process of industrialization and urbanization in China, the energy consumption and greenhouse gases emission of transport sector increased rapidly. From the viewpoint of how the urban traffic management department should cope with the global climate change, based on the economy, institutional reform, planning and policies in China, the paper analyzed the main important problems and obstacles in the development of urban transport, put forward the corresponding policy recommendations which could lead the urban transport system transform to low carbon emission and become more suitable to the climate change.  相似文献   

5.
华北地区1901~2002年气候变化强度的演变   总被引:3,自引:0,他引:3  
利用英国East Anglia大学研究部1901~2002年高分辨率的格点月平均气温和月降水量资料,以及华北地区104个气象观测站1957~2002年的实测月降水量和月平均气温资料,从100a,50a和20a共3个时间尺度详细分析了华北地区潜在蒸发量、降水和气温的趋势变化特征以及气候变化强度的演变规律.结果表明,华北地区的气候变化在百年尺度上经历了由弱到强的变化过程,最近20a(1981~2002年)的气候变化强度是近百年来最强的时期,气候变暖、干旱化趋势加重,潜在蒸发量上升,将会导致华北地区水资源供需矛盾更加突出.  相似文献   

6.
Comprehensive global climate models are the only tools that account for the complex set of processes which will determine future climate change at both a global and regional level. Planners are typically faced with a wide range of predicted changes from different models of unknown relative quality, owing to large but unquantified uncertainties in the modelling process. Here we report a systematic attempt to determine the range of climate changes consistent with these uncertainties, based on a 53-member ensemble of model versions constructed by varying model parameters. We estimate a probability density function for the sensitivity of climate to a doubling of atmospheric carbon dioxide levels, and obtain a 5-95 per cent probability range of 2.4-5.4 degrees C. Our probability density function is constrained by objective estimates of the relative reliability of different model versions, the choice of model parameters that are varied and their uncertainty ranges, specified on the basis of expert advice. Our ensemble produces a range of regional changes much wider than indicated by traditional methods based on scaling the response patterns of an individual simulation.  相似文献   

7.
Climate change in the 21st century over China is simulated using the Abdus Salam International Centre for Theoretical Physics (ICTP) Regional Climate Model version 3 (RegCM3). The model is one-way nested within the global model CCSR/NIES/FRCGC MIROC3.2_hires (Center for Climate System Research/National Institute for Environmental Studies/Frontier Research Center for Global Change/Model for Interdisciplinary Research on Climate). A 150-year (1951-2100) transient simulation is conducted at 25 km grid spacing, under the Intergovernmental Panel on Climate Change Special Report on Emissions Scenarios (IPCC SRES) A1B scenario. Simulations of present climate conditions in China by RegCM3 are compared against observations to assess model performance. Results show that RegCM3 reproduces the observed spatial structure of surface air temperature and precipitation well. Changes in mean temperature and precipitation in December-January-February (DJF) and June-July-August (JJA) during the middle and end of the 21st century are analyzed. Significant future warming is simulated by RegCM3. This warming becomes greater with time, and increased warming is simulated at high latitude and high altitude (Tibetan Plateau) areas. In the middle of the 21st century in DJF, a general increase of precipitation is found in most areas, except over the Tibetan Plateau. Precipitation changes in JJA show an increase over northwest China and a decrease over the Tibetan Plateau. There is a mixture of positive and negative changes in eastern China. The change pattern at the end of the century is generally consistent with that in mid century, except in some small areas, and the magnitude of change is usually larger. In addition, the simulation is compared with a previous simulation of the RegCM3 driven by a different global model, to address uncertainties of the projected climate change in China.  相似文献   

8.
根据相对论中的质能关系E=mc^2,如果一个物体以辐射形式放出能量,那么它的质量就要减少,由于在化学变化中将伴随着能量的释放和吸收,经典化学中的质量守恒定律和相对论中的质能关系是相矛盾的;质能关系的存在表明在化学变化中质量不是守恒的,实际上是质能的守恒.  相似文献   

9.
Wang  Xin  Wang  DongXiao  Gao  RongZhen  Sun  DongHuai 《科学通报(英文版)》2010,55(13):1304-1310
The authors analyze the coral growth band from a colony in the northwestern South China Sea. The coral growth band can provide comprehensive environmental information on climate. The trend from the two-century-long annual density of the coral is in a good agreement with that of the global CO2 concentration. Both trends were small prior to the end of the 19th century; after that, trends became clear, more so from the 1960s to the 1990s (the end of the coral record). The overall coral density shows a steady d...  相似文献   

10.
 随着气候变化及其所带来的影响日益显著,目前适应气候变化越来越成为全球关注的热点问题。东北地区是中国重要的粮食生产基地,气候变化影响下东北农业生产变化将直接引起中国粮食安全问题。从气候变化角度着手,梳理了气候变化对东北农业影响的关键问题,分析指出近年来气候变化对东北地区农业4个最突出的影响:热量资源呈现增加趋势,旱涝灾害频次与强度增大,极端低温冷害事件下降,农业病虫害损失显著加重。针对这4个关键问题,从作物抗逆品种选育、作物应变耕作栽培、农田基本建设、种植结构调整、病虫害防治、农业保险等不同方面形成东北农业适应技术体系框架。  相似文献   

11.
利用1990-2010年神农架林区国家气象站点的气象数据资料,对林区近21年的平均气温、最高气温、最低气温、雨日数、大雨日数、降水量、干旱指数进行分析.结果表明,近21年神农架林区的平均气温呈上升趋势,以春季最为显著;最高气温趋势与平均气温趋势基本一致,全年、春季、夏季及冬季均呈上升趋势,而秋季最高气温有所下降;最低气温亦呈上升趋势,其中冬季最低气温倾向率低于全年水平,春季、夏季和秋季最低气温倾向率高于全年水平;雨日数及大雨日数均呈增加趋势;降水量全年倾向率为正,春夏2季亦为正,秋冬2季则为负;干旱指数各年均〉1,且有变大的趋势.  相似文献   

12.
Using the definition of vulnerability provided by the Intergovernmental Panel on Climate Change,this paper assesses the vulnerability of areas affected by Chinese cryospheric changes from 2001 to 2020 and from 2001 to 2050 in A1 and B1scenarios.Seven indices are used in the vulnerability assessment:glacial area fraction,interannual variability of permafrost depth,interannual variability of surface snow area fraction,interannual variability of surface runoff,interannual variability of surface temperature,interannual variability of vegetation growth,and interannual variability of the human development index.Assessment results show that the overall vulnerability of the studied areas in China increases from east to west.The areas in the middle and eastern parts of China are less vulnerable compared with western parts and parts of the Tibetan Plateau.The highest vulnerability values are found from 1981 to 2000,and the least ones are found from 2001 to 2050.The vulnerable areas increase from the period of 1981 to 2000 to the period of 2001 to 2050,and the less vulnerable areas decrease.The highly vulnerable areas increase from the period of 1981 to 2000 to the period of 2001 to 2020 and then decrease from the period of 2001 to 2020 to the period of 2001 to 2050.This decrease in vulnerability is attributed to the decrease in exposure and sensitivity to Chinese cryospheric changes along with a concomitant increase in adaptation.  相似文献   

13.
黑河流域NPP对气候变化及人类活动的响应?   总被引:1,自引:0,他引:1  
基于改进的CASA光能利用率模型,利用Spot VEGETATION逐旬NDVI数据,对黑河流域1998—2007年植被NPP进行了估算,在掌握10年黑河流域植被NPP变化趋势基础上,探讨不同类型植被NPP对气候变化的响应机制,定量评估2000年后黑河调水与生态保护建设工程的实施效果.结果表明:从1998—2001年间植被覆盖区域年NPP处于显著下降趋势;而2001—2007年间植被类型NPP处于显著上升趋势,2001年成为这10年间NPP趋势变化的转折点.在大规模黑河调水与生态保护建设之后(2002—2007年)的5年期间,黑河上、中、下游所有土地覆盖类型的NPP残差均大于0,表明调水与生态建设工程已经取得成效.人类活动对中游NPP平均贡献率11.5%,对上游NPP平均贡献率5.29%,对下游NPP平均贡献率3.23%.  相似文献   

14.
长江流域森林NPP模拟及其对气候变化的响应   总被引:2,自引:0,他引:2  
【目的】利用LPJ模型(Lund-Potsdam-Jena model)估算长江流域森林净初级生产力(net primary productivity, NPP),研究长江流域森林NPP时空动态变化及其与气候因素的关系,为长江流域及其他地区的植被监测与生态建设提供依据。【方法】基于LPJ模型模拟的NPP数据及气象资料,对长江流域1982—2013年森林NPP的空间分布和时空动态变化趋势进行分析,采用线性回归分析法分别以时间为自变量和NPP为因变量进行趋势检验,利用相关性分析法分析长江流域森林NPP与气象因子之间的关系。【结果】①长江流域1982—2013年森林年均NPP值为530.41 g/(m2·a),最高值出现在2002年,森林NPP值为578.55 g/(m2·a);最低值出现在1989年,森林NPP值为491.24 g/(m2·a)。②长江流域森林NPP的空间分布由东南沿海向西北逐渐减小,长江中下游森林NPP高于长江上游,森林NPP空间分布格局与水热条件分布格局相一致,长江流域东南部水热条件良好,能够满足植被生长和发展的需要,植被生产力比较高;西北部由于水热条件比较差,不利于植被生长,生产力低下。③长江流域大部分地区森林NPP与气温和降水为正相关关系,森林NPP与气温呈显著正相关,气温与森林NPP之间的相关性强于降水与森林NPP之间的相关性。【结论】长江流域森林NPP呈自东南向西北减少的趋势,且随时间呈波动上升趋势;气候对森林NPP具有显著影响,气温是影响森林NPP的主导因素。  相似文献   

15.
选取PMIP2计划中ECBilt-CLIO-VECODE模式的结果,对比中全新世(6 kaBP)气候对于现代气候的变化,探讨了植被在中全新世气候变化中的意义.中东亚干旱区受西风环流影响,而东亚地区6 kaBP季风深入,不同大气环流的影响导致两区域大尺度气候特征差异大,同时该时期植被的变化增强了气候系统对轨道参数变化的响应:一系列气候要素对植被的动态响应导致气温、降水都因植被反馈而发生较大变化,但是该模式的结果存在低估6 kaBP升温幅度的缺陷,尤其是对冬季温度的模拟;即使耦合植被后有所改善,但对6 kaBP气候变化的驱动因子及其相互关系的研究仍需深入,同时对局地气候变化的物理机制还需改进.  相似文献   

16.
目的定量分析西北地区地表植被覆盖的时间变化与空间分布,为其合理开展农业生产,进行环境保护和生态建设提供科学的决策依据。方法利用西北地区1982—2006年GIMMS-NDVI数据,以绿度变化率和偏相关分析法为基础,分析了西北地区不同生态地理分区NDVI的年际变化以及植被覆盖变化对气候要素在空间上的响应。结果近25年来,高原植被覆盖整体呈波动增加的趋势。各生态分区的NDVI均呈增长趋势,并且随着湿润程度和温度的降低,年均NDVI随之减小;1982—2000年降水量在减小,但减小幅度不显著;气温呈显著上升趋势,年均NDVI与气温的相关性较好。结论西北地区的东南部和西北部地区水热组合条件相对于中部地区较好;植被覆盖较好的区域,其改善的趋势明显,相反则不明显;西北地区东部水热组合条件向不利于植被生长方向转变,而西部向利于植被生长的方向发展。  相似文献   

17.
Pienitz R  Vincent WF 《Nature》2000,404(6777):484-487
The effect of stratospheric ozone depletion on increases in ambient levels of solar ultraviolet (UV) radiation in high-latitude regions' has raised concerns about the response of northern ecosystems to environmental change. The concentration of coloured dissolved organic material, which is derived from terrestrial vegetation and acts as a screen for ultraviolet radiation, is low in high-latitude lakes. The underwater light environment in these lakes is therefore likely to be sensitive to small variations in the supply of this material, in addition to the effects of ozone depletion. Here we use fossil diatom assemblages in combination with bio-optical models to estimate the magnitude of past variations in the underwater light regime of a lake at the boreal tree line. We find large shifts in underwater UV-B, UV-A and photosynthetically available radiation associated with changes in the input of coloured dissolved organic material into subarctic lakes during the Holocene. The inferred changes in biological exposure to UV radiation were at least two orders of magnitude greater than those associated with moderate (30%) ozone depletion. Our findings indicate that freshwater ecosystems at present located across vegetation gradients will experience significant shifts in underwater spectral irradiance through the effects of climate change on catchment vegetation and the export of coloured dissolved organic material.  相似文献   

18.
选取西北地区1961~2014年124个气象站点逐日气象资料,分析该区域降水量及可能蒸散量变化特征,采用相对湿润度指数探讨分析该区域四季及喜温、喜凉作物生长季干旱趋势变化特征及其对气候变化的响应。结果表明:(1)西北地区降水量短缺呈增加趋势,可能蒸散量呈减少趋势,二者区域间差异均较大,其上升、下降趋势信度达99%及无明显变化站点分别占西北地区总站点的23.4%、0.8%、75.8%和18.5%、31.5%、50%。(2)西北地区相对湿润度表现为春季多特旱,夏秋两季多轻旱,冬季及喜温、喜凉作物生长季多中旱,且秋季呈变干趋势,其余各时段呈变湿趋势,春、夏、冬三季极为显著,空间上总体呈东南向西北逐渐递增后趋缓的趋势。(3)西北地区不同干旱发生频率总体呈现出春季冬季秋季夏季,喜温作物生长季喜凉作物生长季,而干旱频率区域分布特征与相对湿润度基本一致。(4)西北地区各时段日平均气温均呈显著增加趋势,降水量在秋季表现为减少趋势,其余各时段均呈增加趋势;日照时数在春季、喜温和喜凉作物生长季表现为增加趋势,而在夏、秋、冬三季表现为下降趋势;相对湿度、风速在各时段均表现为减少趋势。(5)相对湿润度指数M与各时段降水量、日照时数及相对湿度的相关性最大,与各时段风速及日平均气温也存在一定的相关性。  相似文献   

19.
基于MODIS-NDVI遥感数据反演新疆乌苏地区2001~2013年植被覆盖的空间格局和变化规律;并结合研究区同期降水量和气温数据,分析了乌苏天山森林生态区、东南部草原生态区和西北部荒漠生态区植被的年际变化和季节变化对气候变化的响应.结果表明:①从年际变化上看,乌苏13 a间NDVI呈现缓慢降低趋势,平均NDVI达到了0.163;乌苏东北部及天山北坡部分NDVI较高,西北荒漠地带和中部精河、车排字、克拉玛依一线较低,空间分布呈现南北两极分化;(②年内变化,乌苏NDVI变化曲线呈现单峰型,7~8月达到最高,10月至翌年2月植物枯黄NDVI逐渐降低;③在年际水平上,乌苏植被覆盖与气温降水的相关性不高.但在年内水平上,气候因子对植被生长的影响作用明显,气温与月均NDVI通过0.01的显著性检验,达到0.964.说明年内植被生长更依赖于水热组合的作用,而且温度是影响植物生长最直接的因素之一.  相似文献   

20.
统计降尺度对西北地区未来气候变化预估   总被引:6,自引:1,他引:6  
利用IPCC数据分发中心提供的模式集成结果和多年的观测资料,建立大尺度气候状况(主要是降水与气温)与区域地理位置和海拔的统计降尺度关系,并用独立的观测资料检验这种关系,实现西北地区高分辨率气候空间分布;然后把这种关系应用于AOGCMs输出的大尺度气候信息,预估西北地区未来的气候变化情景.结果表明:与20世纪后半期相比,未来30年中国西北地区将普遍增温,增温幅度显著的地区在甘肃中东部、内蒙古、宁夏、陕西中北部、青海东北部和新疆的天山及阿尔泰山,增温幅度为0.5-1.0℃;降幅较大的地区在塔里木盆地,降幅为0.5-1.32℃;降水普遍增加,增加比较显著的地区有新疆的塔里木盆地南部、阿尔泰山和天山,陕西省南部,增加幅度为25-78 mm/年,降水减少的地区在高原区,青海省最为显著,减少幅度为81-108 mm/年.  相似文献   

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