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气候变化对长江黄河源区生态系统的影响及其水文效应 总被引：10，自引：0，他引：10
利用1967年航片数据、1986和2000年两期遥感TM数据，对长江黄河源区高寒生态系统分布格局变化进行了分析，并结合源区气候变化观测数据，分析了源区高寒生态系统变化与气候的关系和陆面生态系统变化对源区水文过程的影响。结果表明：过去40 a来，长江源区高覆盖草甸、高覆盖草原和湿地面积分别减少了13.5%、3.6%和28.9%，黄河源区高覆盖草甸、高覆盖草原和湿地面积分别减少了23.2%、7.0%和13.6%，江河源区低覆盖草甸、草原和沙漠草地面积均不同程度地增加；长江、黄河源区气温变化率分别为0.27和0.31℃/10a，降水的变化趋势在长江、黄河源区分别以0.36和0.07 mm/a的速率递增，气温持续升高和由此引起的冻土退化是导致高寒生态系统退化的主要因素之一；陆面生态系统退化对源区水文过程影响显著，在降水没有明显变化的情况下，长江、黄河源区径流系数分别由1960年代的0.16和0.28下降到21世纪的0.12和0.21，且降水－径流关系减弱，出源径流趋于减少，洪水发生频率显著增加，水源涵养指数持续减小。如何应对气候变化，维护源区高寒生态系统功能，已成为迫切需要关注和解决的关键问题。 相似文献
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根据１９８９年冬季，在我省西南部大凉山海拔高度２０００—２９００ｍ的高寒重冰区，进行的云雾及气象条件的梯度观测。对冰区云雾中云雾滴谱、滴的分布特征和滴的浓度、尺度、液态含水量及随距地高度的变化等进行了分析研究，揭示了高海拔高寒重冰区云雾的一些基本特征。 相似文献
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川西高原水稻种植面积集中于凉山州，海拔1800m及以上高寒稻区，水稻采用地膜覆盖移栽技术，在大田营养生产期地温增温效应十分显著，促使水稻农艺性状得到明显改善，提高了分蘖力，增加了穗粒数，达到了显著增产的目地。 相似文献
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川西高原水稻种植面积集中于凉山州，海拔1800m及以上高寒稻区，水稻采用地膜覆盖移裁技术，在大田营养生产期地温增温效应十分显著，促使水稻农艺性状得到明显改善，提高了分蘖力，增加了穗粒数，达到了显著增产的目的。 相似文献
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岷县防雹作业炮点布局和通讯网建设丁阜朝（兰州干旱气象研究所７３００２０）岷县地处黄土高原和青藏高原的过度地带，山大沟深，沟壑纵横，形成了特殊的地理位置和地形地貌。气候特点是由北向南从温凉半湿润气候向寒冷湿润气候过度。因此，形成了高寒阴湿、低温寡照、气... 相似文献
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基于高寒内流区26个国家气象站的日气温资料,利用线性趋势法、5年滑动平均等方法分析高寒内流区近49年升温特征,结果表明：（1）1969-2017年,高寒内流区整体暖化。平均气温、平均最高气温、平均最低气温均呈显著上升趋势,年平均最低气温的上升趋势是年平均最高气温的1.5倍。空间上平均最高和最低气温均呈由东南向西北增加的趋势。（2）极端气温指数暖化趋势明显,生长季长度、极端气温暖指数以及一些冷指数（日最高气温的极低值）在高寒内流区北部增暖幅度较大,冰冻日数、霜冻日数在高寒内流区西南部、南部增温明显。暖指数和生长季长度自20世纪60年代以来呈上升趋势,而一些冷指数（冷昼日数和冷夜日数）、冰冻日数、霜冻日数和气温日较差的斜率多年来呈下降趋势。（3）冷指数的减小幅度大于暖指数的增大幅度,夜指数的减小幅度大于昼指数的增大幅度。（4）高寒内流区极端高温指数（日最高气温的极高值和日最高气温的极低值）受海拔影响较大;极端高温事件主要发生在低海拔区;极端气温随着大西洋副高强度增加、面积增大、脊线指数偏大,北界指数偏大,西太平洋副高位置偏东、强度加大呈增暖趋势。 相似文献
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华亭县玉米产量与气象条件关系和预报模式 总被引：1，自引：0，他引：1
华亭县玉米产量与气象条件关系和预报模式缪翔汝淑玲（华亭县气象局７４４１００）玉米是华亭县主要秋粮作物之一，年种植面积为７３３３ｈｍ２，占粮田总面积的３１％。由于该县地处高寒阴湿山区，地理环境复杂，气候差异较大，农业生产水平较低，玉米产量的丰欠对全年粮... 相似文献
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在高寒阴湿、半干旱地带、徽成盆地推广地膜覆盖小麦、玉米、洋芋是一项增产效益显著 ,帮助农民脱贫的适用技术。它可有效地补偿热量 ,提高地温 ,调节水分 ,促进土壤熟化 ,充分利用光、热、水资源 ,促进作物生长和提早成熟 ,提高粮食产量。该地区山大沟深 ,高差悬殊 ,气候类型多样 ,为了因气候制宜覆盖地膜 ,充分发挥地膜增产优势 ,开展小麦、玉米、马铃薯地膜栽培界限及农田小气候效应的研究。1 试验研究方法1 .1 试验方法在高寒阴湿的宕昌木耳乡、武都金厂渭子坪 ,半干旱地带的礼县、西和、康县、武都、徽成盆地等适宜种植区域 ,海拔 1 … 相似文献
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The response of plant species to future climate conditions is probably dependent on their ecological characteristics, including climatic niche, demographic rates and functional traits. Using forest inventory data from 27 dominant woody species in Spanish forests, we explore the relationships between species characteristics and projected changes in their average climatic suitability (occurrence of suitable climatic conditions for a species in a given territory) obtained by empirical niche-based models, under a business-as-usual climate change scenario (A1, HadCM3, 2001–2100). We hypothesize that most species will suffer a decline in climatic suitability, with a less severe for species (i) currently living in more arid climates or exhibiting a broader current climatic niche; (ii) with higher current growth rates; (iii) with functional traits related to resistance to water deficits. The analysis confirm our hypothesis since apart from a few Mediterranean species, most species decrease their climatic suitability in the region under future climate, characterized by increased aridity. Also, species living in warmer locations or under a wider range of climatic conditions tend to experience less decrease in climatic suitability. As hypothesized, a positive relationship was detected between current relative growth rates and increase in future climatic suitability. Nevertheless, current tree mortality did not correlate with changes in future climatic suitability. In contrast with our hypothesis, functional traits did not show a clear relationship with changes in climate suitability; instead species often presented idiosyncratic responses that, in some cases, could reflect past management. These results suggest that the extrapolation of species performance to future climatic scenarios based on current patterns of dominance is constrained by factors other than species autoecology, particularly human activity. 相似文献
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There is abundant historical evidence that climatic extremes in the past have led to significant and sometimes severe societal
impacts. The severity of these impacts depends on the intensity and duration of the climatic event, social organization, and
the prevailing socioeconomic conditions at the time of the climatic extreme. In this issue of Climatic Change we present the results from 12 studies, which document climatic extremes on different time scales and provide interesting
evidence for direct and indirect social impacts of climatic changes in the Americas during the pre-Hispanic, colonial, and
modern eras. 相似文献
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云南烤烟气候类型及其适宜性研究 总被引：12，自引：0，他引：12
根据云南烤烟气候特点，提出了判别云南烤烟气候类型及其适宜性的指标：热量为一级指标，降水和光照为二级指标。采用综合指标法评判热量条件，对其他多个气候条件应用系统聚类分析，并结合云南烤烟生产实践经验，对云南全部气象站点进行烤烟气候类型划分和适宜性评价。从而得出云南烤烟气候最适宜区和适宜区的地理分布、以及制约云南烤烟种植的主要气候原因，为云南烤烟合理布局和烤烟生产提供了科学依据。 相似文献
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Possible Effects of Global Warming on Agriculture and Water Resources in Saudi Arabia: Impacts and Responses 总被引：2，自引：0，他引：2
Fahad M. Alkolibi 《Climatic change》2002,54(1-2):225-245
This study assesses the possible impact of climatic change on Saudi Arabia's agriculture and water supplies using climatic change scenarios from GCMs (General Circulation Models) and related research. The resulting assessment indicates that an increase in temperature and decrease in precipitation could have a major negative impact on agriculture and water supplies in Saudi Arabia. To find signs of climatic change in Saudi Arabia a preliminaryassessment of systematic changes in temperature and precipitation was made, based on the records of four Saudi weather stations. The analysis of this data, which dates back to 1961, shows no discernable signs of climatic change during the study period. Such data is, however, limited both spatially and temporally and cannot provide conclusive evidence to confirm climatic changes projected by GCMs. Nevertheless, in the light of recent climatic conditions and rapid population growth, Saudi decision-makers are urged to adopt a `no regret' policy. Ideally, such a policy would include measures to avoid future environmental or socioeconomic problems that may occur in the event of significant climatic change. 相似文献
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近50年平凉地区气候变化及其对农业生产的影响 总被引：14，自引：3，他引：14
利用统计学方法对80年代前后平凉地区的气候变化特点进行了研究，并分析了气候变化对农业生产所产生的影响，为合理利用本地气候资源提供依据。 相似文献
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Christopher R. Bryant Barry Smit Michael Brklacich Thomas R. Johnston John Smithers Quentin Chjotti Bhawan Singh 《Climatic change》2000,45(1):181-201
The effects of climatic variability and change on Canadian agriculture have become an important research field since the early 1980s. In this paper, we seek to synthesize this research, focusing on agricultural adaptation, a purposeful proactive or reactive response to changes associated with climate, and influenced by many factors. A distinctive feature of methods used in research on adaptation in Canadian agriculture is the focus on the important role of human agency. Many individual farmers perceive they are well adapted to climate, because of their extensive 'technological' tool-kit, giving them confidence in dealing with climatic change. In many regions, little concern is expressed over climatic change, except where there are particular types of climatic vulnerability. Farmers respond to biophysical factors, including climate, as they interact with a complex of human factors. Several of these, notably institutional and political ones, have tended to diminish the farm-level risks stemming from climatic variability and change, but may well increase the long term vulnerability of Canadian agriculture. Notwithstanding the technological and management adaptation measures available to producers, Canadian agriculture remains vulnerable to climatic variability and to climate change. 相似文献
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分析了黄河三角洲地区主要栽培草种的气候生态适应性以及牧草生长季气候条件的优劣势。计算得出该区天然草场和人工草场的气候生产力、气候增产潜力，研究其时空分布规律，提出草场改良措施。结果表明：天然草场年气候生产力为９２１０—１１８２０ｋｇ／ｈａ。增产潜力为４５００—１０５００ｋｇ／ｈａ；种植紫花苜蓿的人工草场年气候生产力为２３７７５—２８０８０ｋｇ／ｈａ，增产潜力为６０００—１９５００ｋｇ／ｈａ。 相似文献
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B. G. Hunt 《Climate Dynamics》2011,36(3-4):509-521
Controversy continues to prevail concerning the reality of anthropogenically-induced climatic warming. One of the principal issues is the cause of the hiatus in the current global warming trend. There appears to be a widely held view that climatic change warming should exhibit an inexorable upwards trend, a view that implies there is no longer any input by climatic variability in the existing climatic system. The relative roles of climatic change and climatic variability are examined here using the same coupled global climatic model. For the former, the model is run using a specified CO2 growth scenario, while the latter consisted of a multi-millennial simulation where any climatic variability was attributable solely to internal processes within the climatic system. It is shown that internal climatic variability can produce global mean surface temperature anomalies of ±0.25?K and sustained positive and negative anomalies sufficient to account for the anomalous warming of the 1940s as well as the present hiatus in the observed global warming. The characteristics of the internally-induced negative temperature anomalies are such that if this internal natural variability is the cause of the observed hiatus, then a resumption of the observed global warming trend is to be expected within the next few years. 相似文献