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European phenological response to climate change matches the warming pattern   总被引:20,自引:0,他引:20  
《Global Change Biology》2006,12(10):1969-1976
Global climate change impacts can already be tracked in many physical and biological systems; in particular, terrestrial ecosystems provide a consistent picture of observed changes. One of the preferred indicators is phenology, the science of natural recurring events, as their recorded dates provide a high-temporal resolution of ongoing changes. Thus, numerous analyses have demonstrated an earlier onset of spring events for mid and higher latitudes and a lengthening of the growing season. However, published single-site or single-species studies are particularly open to suspicion of being biased towards predominantly reporting climate change-induced impacts. No comprehensive study or meta-analysis has so far examined the possible lack of evidence for changes or shifts at sites where no temperature change is observed. We used an enormous systematic phenological network data set of more than 125 000 observational series of 542 plant and 19 animal species in 21 European countries (1971–2000). Our results showed that 78% of all leafing, flowering and fruiting records advanced (30% significantly) and only 3% were significantly delayed, whereas the signal of leaf colouring/fall is ambiguous. We conclude that previously published results of phenological changes were not biased by reporting or publication predisposition: the average advance of spring/summer was 2.5 days decade−1 in Europe. Our analysis of 254 mean national time series undoubtedly demonstrates that species' phenology is responsive to temperature of the preceding months (mean advance of spring/summer by 2.5 days°C−1, delay of leaf colouring and fall by 1.0 day°C−1). The pattern of observed change in spring efficiently matches measured national warming across 19 European countries (correlation coefficient r =−0.69, P <0.001).  相似文献
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张学雷  陈杰  龚子铜 《生态学报》2004,24(5):1063-1072
介绍了土壤多样性理论的基本概念与研究方法以及在西班牙、美国等欧美国家的研究实践 ,包括在欧盟 CORINE数据库和美国 STATSGO数据库支持下进行的多样性主要指数 (多样性指数、均匀度指数和多度指数等 )的算法、主要模型 (多度分布模型、幂律模型等 )的分析、GIS和地统计学方法的应用等。通过这些研究实践 ,可以看出土壤多样性理论在研究土壤的空间可变性、土壤景观格局的相互关系 ,土地利用与城市化过程对土壤多样性的影响等方面确有独到之处 ,为解决当前我国土壤学面临的环境资源可持续发展、环境监控、基因保护、城市化过程等热点问题提供了一个崭新的研究思路 ,展现出良好的应用前景  相似文献
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Trends in phenological phases in Europe between 1951 and 1996   总被引:12,自引:0,他引:12  
Increases in air temperature due to the anthropogenic greenhouse effect can be detected easily in the phenological data of Europe within the last four decades because spring phenological events are particularly sensitive to temperature. Our new analysis of observational data from the International Phenological Gardens in Europe for the 1959–1996 period revealed that spring events, such as leaf unfolding, have advanced on average by 6.3 days (–0.21 day/year), whereas autumn events, such as leaf colouring, have been delayed on average by 4.5 days (+0.15 day/year). Thus, the average annual growing season has lengthened on average by 10.8 days since the early 1960s. For autumn events, differences between mean trends of species could not be detected, but for spring events there were differences between species, with the higher trends for leaf unfolding and flowering of shrubs indicating that changes in events occurring in the early spring are more distinct. These observed trends in plant phenological events in the International Phenological Gardens and results of other phenological studies in Europe, summarised in this study, are consistent with AVHRR satellite measurements of the normalized difference vegetation index from 1981 to 1991 and with an analysis of long-term measurements of the annual cycle of CO2 concentration in Hawaii and Alaska, also indicating a global lengthening of the growing season. Received: 21 October 1999 / Accepted: 2 March 2000  相似文献
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现代人头骨面部某些特征的投影栅相位法测量研究   总被引:9,自引:0,他引:9  
用投影栅相位法,定量测量现代人面颅骨的一些项目,分析比较了中国南方、北方面骨的特点及中国与欧洲现代人面骨的差异,并探讨该方法在人类学研究领域应用的可行性和实用性。发现:1.不论云南、欧洲头髓,性别差异主要集中在线距项目上,男性测量值大于女性。2.华北头骨的蝇面宽、上面高及其指数、或讪命高和内侧两眶宽指数大于云南头骨,中面部的扁平度小于云南头骨,颧骨额蝶突的前外侧而比云南头骨的要朝向前方;3.中国云南、华北现代人头骨上面部的宽度小于欧洲现代人头骨,上面部平程序大于欧洲的现代头骨;颧骨额蝶突的前外侧面比欧洲头骨更朝向前 方,。华北头髓上面部高度及其指数大于欧洲头骨。运动头上面高及性的上百高数与欧洲无头无差异,云南女性上面高指数大于欧洲头髓,我们为投影栅相位法可作为传统的有益补充。  相似文献
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