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冬季最低温和温度季节变异对北美树木分布北界及多样性的调控研究

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Journal of Geographical Sciences 2022年第2期32卷 280-290页

作者：钱宏张扬建 Robert E.RICKLEFS 王宪礼 Research and Collections Center Illinois State Museum1011 East Ash StreetSpringfieldIL 62703USA Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources ResearchCASBeijing 100101China Department of Biology University of Missouri–St.LouisSt.LouisMO 63121USA Northern Forestry Centre Canadian Forest ServiceNatural Resources Canada5320-122nd StreetEdmontonAB T6H 3S5Canada Department of Renewable Resources University of Alberta751 General Service Building EdmontonAB T6G 2H1Canada

Biologists have considered both winter coldness and temperature seasonality as major determinants of the northern limits of plants and animals in the Northern Hemisphere,which in turn drive the well-known latitudinal diversity gradient.However,few studies have tested which of the two climate variables is the primary determinant.In this study,we assess whether winter coldness or temperature seasonality is more strongly associated with the northern latitudinal limits of tree species and with tree species richness in North America.Tree species were recorded in each of 1198 quadrats of 110 km×110 km in North America.We used correlation and regression analyses to assess the relationship of the latitude of the northern boundary of each species,and of species richness per quadrat,with winter coldness and temperature seasonality.Species richness was analyzed within 38 longitudinal,i.e.,north-south,bands(each being>1100 km long and 110 km wide).The latitudes of the northern range limits of tree species were three times better correlated with minimum temperatures at those latitudes than with temperature seasonality.On average,minimum temperature and temperature seasonality together explained 81.5%of the variation in the northern range limits of the tree species examined,and minimum temperature uniquely explained six-fold(33.7%versus 5.8%)more of this variation than did temperature seasonality.Correlations of tree species richness with minimum temperatures were stronger than correlations with temperature seasonality for most of the longitudinal bands analyzed.Compared to temperature seasonality,winter coldness is more strongly associated with species distributions at high latitudes,and is likely a more important driver of the latitudinal diversity gradient.

关键词： cold tolerance latitudinal diversity gradient minimum temperature temperature seasonality temperature variation trees tropical conservatism hypothesis

Effect of temperature on Frost-Free Days and Length of Crop Growing Season across Southern Ontario

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American Journal of Climate Change 2023年第4期12卷 700-718页

作者： Ramesh Pall Rudra Rituraj Shukla Trevor Dickinson Pradeep Kumar Goel Jaskaran Dhiman School of Engineering University of Guelph Guelph Canada The Faculty of Agricultural and Environmental Sciences McGill University Montreal Canada

Climate change has an impact on various climatic variables. In this study our focus is mainly on temperature characteristics of climate parameter. In temperate and humid regions like southern Ontario, the effect of climate change on Frost-free days in winter is distinctive. The average annual temperature is going upward but the extreme increase is in the winter temperature. Winter average temperature is going up by about 2˚C. However, extreme daily minimum temperature is going up by more than 3˚C. This climate effect has a great impact on the nature of precipitation and length of frost-free days. The snowfall over winter months is decreasing and the rainfall is increasing. However, the number of frost-free days during late fall months, early winter months, late winter months and early spring months are increasing. This result reveals an increase in length of the growing season. This research focuses on the effect of change in climatic variables on Frost-free days in Southern Ontario. Therefore, special attention should be given to the effect of change in climate Frost-free conditions on length of crop growing in winter season for potential investigation.

关键词： Climate Change minimum temperature Frost-Free Days Snowfall Crop Growing Season Southern Ontario

Analysis of Sampling Error Uncertainties and Trends in Maximum and minimum temperatures in China

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Advances in Atmospheric Sciences 2014年第2期31卷 263-272页

作者： HUA Wei Samuel S.P.SHEN WANG Huijun Nansen-Zhu International Research Centre Institute of Atmospheric Physics Chinese Academy of Sciences Department of Atmospheric Sciences Chengdu University of Information Technology University of the Chinese Academy of Sciences Department of Mathematics and Statistics San Diego State University

In this paper we report an analysis of sampling error uncertainties in mean maximum and minimum temperatures （Tmax and Tmin） carried out on monthly,seasonal and annual scales,including an examination of homogenized and original data collected at 731 meteorological stations across China for the period 1951-2004.Uncertainties of the gridded data and national average,linear trends and their uncertainties,as well as the homogenization effect on uncertainties are assessed.It is shown that the sampling error variances of homogenized Tmax and Tmin,which are larger in winter than in summer,have a marked northwest-southeast gradient distribution,while the sampling error variances of the original data are found to be larger and irregular.Tmax and Tmin increase in all months of the year in the study period 1951-2004,with the largest warming and uncertainties being 0.400℃ （10 yr）-1 ＋ 0.269℃ （10 yr）-1 and 0.578℃ （10 yr）-1 ＋ 0.211℃ （10 yr）-1 in February,and the least being 0.022℃ （10 yr）-1 ＋ 0.085℃ （10 yr）-1 and 0.104℃ （10 yr）-1 ＋0.070℃ （10 yr）-1 in August.Homogenization can remove large uncertainties in the original records resulting from various non-natural changes in China.

关键词： sampling error uncertainty maximum temperature minimum temperature temperature trend

The effect of low-temperature event on the survival and growth of Juglans mandshurica seedlings within forest gaps

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Journal of Forestry Research 2018年第4期29卷 939-947页

作者： Xiufen Li Yongjing Wen Jinxin Zhang Limin Liu Lei Jin Tao Yan Yi Wang Agronomy college Shenyang Agricultural University Qingyuan Forest CERN Chinese Academy of Sciences Institute of Applied Ecology Chinese Academy of Sciences

In forest ecosystems, gap formation changes the allocation of abiotic resources and thus affects the survival and growth of understory plants. However, how tree seedling survival and growth respond to low-temperature events and the influencing mechanisms remain unclear. To clarify how low-temperature event limits the survival and growth of tree seedlings in the montane regions of eastern Liaoning Province, northeast China, we investigated temperature and light intensity within secondary forest gaps, and the survival and growth of Juglans mandshurica seedlings after a low-temperature event in the spring of 2014. Damage to seedlings due to low temperature sig- nificantly varied in different aspects. Seedlings in gaps on southeast-facing slopes were the most seriously damaged, followed by those in gaps on northeast-facing slopes. In contrast, seedlings in west-facing gaps and in control plots without slope aspect were not damaged. The freezing injury index for seedlings was negatively correlated with minimum temperature （r = - 0.608, P 〈 0.01）, but it was positively correlated with light intensity （r= 0.818, P 〈 0.01）. In addition, height and root collar diameter of damaged seedlings were significantly lower than those of the undamaged seedlings （P 〈 0.01） during the early growing season （April-July）, but no significant difference were observed during the late growing season （July-Oc- tober）（P 〉 0.05）. The extent of seedling damage was directly related to slope aspect. Low temperature and high light intensity were found to be the dominant factors affecting extent of damage to seedlings on southeast- and northeast-facing slopes.

关键词： Secondary forest gap Freezing injury index minimum temperature Light intensity Slope aspect

Study on Temporal-spatial Change Characteristics of the Extremely Low temperature Climate Event in Winter of China

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Meteorological and Environmental Research 2013年第4期4卷 10-13,16页

作者： Zhonghong Luo Hangdong Jiang Jiangyong Pan Jiayou Huang Xiamen Air Traffic Management Station of CAAC Qingdao Air Traffic Management Station of CAAC Department of Atmospheric and Oceanic Sciences School of Physics Peking University

[ Objective] The research aimed to study temporal-spatial change characteristics of the extremely low temperature climate event in winter of China. [MethodI By using actual probability distribution threshold value method, EOF analysis method and the daily minimum temperature data in winter of 1961 -2008 at 195 observatories of China, temporal-spatial change characteristics of the extremely low temperature climate event in win- ter of China in 48 years were analyzed. [ Result] Threshold value calculated by actual probability distribution was higher than that by traditional method, and increase magnitude in east was bigger than that in west, which could describe climatic change situation in China in 48 years better than traditional method. Cold night number in winter of China did not decrease as latitude declined, and it was more in south and north and was less in Yellow River basin and northwest China. Cold night number was the most in northeast Inner Mongolia. Interannual change of the cold night number presented decline tendency. From the 1960s to the eady 1970s, cold night number consistently increased, and change in middle and late periods of the 1960s was severe. From the early 1970s to the middle 1980s, fluctuation of the cold night number was bigger, and increase of the cold night number was the most in 1976. Cold night number from 1986 to the 21= century continuously declined. Change of the cold night number was the most obvious in east region, Guizhou and north Guangxi. Cold night number in northeast China and north Inner Mongolia presented inverting change relationship with that in Yunnan - Kweichow Plateau and Hexi Corridor. [ Conclusion] The research provided reference for eady warning of the extremely low temoerature event in China.

关键词： minimum temperature Extremely low temperature event Cold night Temporal-spatial change characteristics China

The Highest and Lowest temperature Changes in Dongling in Shenyang from 1951 to 2008

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Meteorological and Environmental Research 2011年第3期2卷 33-35,38页

作者： DONG Xiao-ming,DIAO Jun,LIU Feng-zhi,HE Ming-hui Dongling District Meteorological Bureau in Liaoning Province,Shenyang 110168,China

[Objective] The aim was to study the characteristics of climate changes of highest and lowest temperature in Dongling District in Shenyang Province in recent 58 years.[Method] By dint of the highest temperature and lowest temperature in the meteorological observation station in Dongling District in Shenyang from 1951 to 2008,and through statistical method such as climate tendency rate and sequence relevance,the interannual trend changes of annual and seasonal average highest and lowest temperature were expounded.[Result] In recent 58 years,the annual and seasonal average highest and lowest temperature in Dongling District in Shenyang were increasing and the changes rate of average lowest temperatures (0.262 ℃/10 a) were larger than the rate of average highest temperature (0.187 ℃/10 a).The abrupt changes period was one era earlier than average highest temperature.The annual average highest temperature increased from 1980s and it reached historical new record in late 1990s;while annual lowest temperature stared from 1970s and reached historical new high in 1980s.The average highest temperature and lowest temperature increased most distinctly in winter,followed by spring and was weakest in summer.The differences of annual and seasonal average temperatures were declining and the significance level was low.[Conclusion] The study provided theoretical basis for the development and utilization of climate resources in Shenyang.

关键词： Shenyang Highest temperature minimum temperature Trends Inclination rate China

Variation Characteristics of Winter temperature in Jinan in Recent 60 Years

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Meteorological and Environmental Research 2011年第7期2卷 9-11页

作者： ZHANG Li Department of Policies and Statutes,Shandong Meteorological Bureau,Jinan 250013,China

[Objective] The research aimed to study the variation characteristics of winter temperature in Jinan in recent 60 years.[Method] Based on winter monthly average,maximum and minimum temperatures in the ground observation station of Jinan during 1951-2010,by using linear trend,5-year moving average and anomaly,the variation characteristics of winter average,maximum and minimum temperatures in Jinan in recent 60 years were analyzed.The historical evolution trend and decadal variation characteristics were discussed.[Result] Winter average,maximum and minimum temperatures in Jinan in recent 60 years all presented slow fluctuation rise trend.The rise trend was obvious.Especially the increase amplitude of minimum temperature was the maximum.It illustrated that the variation of minimum temperature was more sensitive than that of maximum temperature,and the climatic warming in winter was mainly from the contribution of minimum temperature rise.Seen from the decadal variation,cold winter mainly appeared before the 1970s.Then,it presented obvious decrease trend.Conversely,warm winter presented increase trend after the 1970s.Warm winter phenomenon slowed after 2000.Winter temperature presented stepped warming trend during 1950s-1990s.Winter average temperature presented jumped warming trend when entered into the 1990s.The temperature presented downward trend when entered into the 21st century.But winter temperature still presented rise trend as a whole.The population growth in Jinan made that urbanization process accelerated,and urban heat island effect aggravated.It was one of important factors for climate warming in Jinan.[Conclusion] The research provided theoretical basis for understanding the long-term variation trend of climate in Jinan area,and if it was consistent with the background of global climatic warming.

关键词： Winter temperature Maximum temperature minimum temperature Variation characteristic China