Correlating tree-ring parameters with daily resolved climate data is becoming increasingly common for understanding the complex relationships between tree growth and the surrounding environment.However,with an increas...Correlating tree-ring parameters with daily resolved climate data is becoming increasingly common for understanding the complex relationships between tree growth and the surrounding environment.However,with an increased number of calculated correlations,there is an inherent risk of spurious significance.In this study,we present an analysis using synthetic weather and tree-ring data mimicking the statistical properties of ten real-world sites across Europe to quantify the extent to which numerous comparisons may inflate maximum correlations.Comparisons of different tree-ring proxies,considering varying overlapping period lengths and seasons,revealed 95th percentile correlation differences reaching 0.25 by chance.Using synthetic tree-ring chronologies with an assigned non-signal(r=0.00),spurious correlations can reach statistical significance in over 60%of tests.Correlation inflation is greater when:(1)the climate-proxy relationship is weaker;(2)comparison periods are shorter;and(3)the length of seasonal windows is longer.Autocorrelation in the proxy records does not appear to have a major effect.These findings indicate that caution should be exercised when computing high numbers of correlations with limited observations.We provide tables listing correlation inflations for precipitation-and temperature-sensitive tree-ring chronologies that can inform interpretations of significance.展开更多
[目的]分析三峡库区消落带水桦在水淹胁迫下的差异表达基因(DEGs)及关键代谢通路,为阐明水桦抗水淹胁迫的分子机制及消落带苗木选育提供理论依据。[方法]以三峡库区消落带(万州段)栽培的水桦为试验材料,采集水淹约70和200 d的枝条(分别...[目的]分析三峡库区消落带水桦在水淹胁迫下的差异表达基因(DEGs)及关键代谢通路,为阐明水桦抗水淹胁迫的分子机制及消落带苗木选育提供理论依据。[方法]以三峡库区消落带(万州段)栽培的水桦为试验材料,采集水淹约70和200 d的枝条(分别标记为FB70d和FB200d)和根系(分别标记为FR70d和FR200d),并以同期未被水淹的枝条(分别标记为CB70d和CB200d)和根系(分别标记为CR70d和CR200d)为对照,进行转录组测序,筛选CR70d vs FR70d组、CR200d vs FR200d组、CB70d vs FB70d组和CB200d vs FB200d组4个比较组的DEGs,对DEGs进行功能注释及KEGG信号通路富集分析并构建蛋白互作网络。对6个DEGs进行实时荧光定量PCR检测,验证转录组测序数据的可靠性。通过不同浓度乙烯喷施水桦离体枝条研究乙烯对水桦枝条的抗逆影响。[结果]在24个样本中共获得155.99 Gb的有效序列,GC含量为46.00%~48.00%,Q30>92.44%;4个比较组中共筛选出10020个DEGs,其中4389个DEGs上调表达,5631个DEGs下调表达。CB200d vs FB200d组和CB70d vs FB70d组中共有956个DEGs,CR200d vs FR200d组和CR70d vs FR70d组中共有17个DEGs。共有7220个DEGs被注释到生物过程、分子功能和细胞组分三大功能类别上。KEGG信号通路富集分析结果显示,植物激素信号转导通路是DEGs富集最明显的通路。有4个DEGs编码蛋白参与的蛋白调控网络最多。4个比较组中,植物激素信号转导通路共有的基因为35个,其中CR200d vs FR200d组和CB200d vs FB200d组的表达发生改变的基因最多,分别有24和32个。乙烯激活因子基因(ERF1和ERF2)在CB70d vs FB70d组和CB200d vs FB200d组表达上调,而在CR70d vs FR70d组和CR200d vs FR200d组无变化。在ABA生物合成通路中,除CR70d vs FR70d组外,SnRK2基因在其他3个比较组均表达下调。大部分基因的转录组测序结果与实时荧光定量PCR检测结果的变化趋势一致。不同浓度乙烯处理10 d后,与对照相比,3个不同浓度乙烯处理下水桦枝条均能保持幼嫩的生长状态。[结论]水淹后水桦枝条基因对胁迫的响应敏感性高于根系。在植物激素信号转导关键信号通路上,筛选到2个响应水淹胁迫的乙烯激活因子基因(ERF1和ERF2)用于下一步功能验证研究。展开更多
In the context of ongoing climate change,rela-tionships between tree growth and climate present uncertain-ties,which limits the predictions of future forest dynamics.Northwest China is a region undergoing notable warm...In the context of ongoing climate change,rela-tionships between tree growth and climate present uncertain-ties,which limits the predictions of future forest dynamics.Northwest China is a region undergoing notable warming and increased precipitation;how forests in this region will respond to climate change has not been fully understood.We used dendrochronological methods to examine the rela-tionship between climate and the radial growth of four tree species in a riparian forest habitat in Altai region:European aspen(Populus tremula),bitter poplar(Populus laurifolia),Swedish birch(Betula pendula),and Siberian spruce(Picea obovata).The results reveal that European aspen was insen-sitive to climate changes.In contrast,bitter poplar showed a positive response to elevated temperatures and negative to increased moisture during the growing season.Swedish birch and Siberian spruce were adversely affected by higher temperatures but benefited from increased precipitation.A moving correlation analysis suggested that,against a back-drop of continuous warming,growth patterns of these spe-cies will diverge:European aspen will require close moni-toring,bitter poplar may likely to show accelerated growth,and the growth of Swedish birch and Siberian spruce may be inhibited,leading to a decline.These findings offer insight into the future dynamics of riparian forests under changing climate.展开更多
基金supported partly by the ERC Advanced Grant Monostar(AdG 882727)the co funded EU project AdAgriF(CZ.02.01.01/00/22_008/0004635).
文摘Correlating tree-ring parameters with daily resolved climate data is becoming increasingly common for understanding the complex relationships between tree growth and the surrounding environment.However,with an increased number of calculated correlations,there is an inherent risk of spurious significance.In this study,we present an analysis using synthetic weather and tree-ring data mimicking the statistical properties of ten real-world sites across Europe to quantify the extent to which numerous comparisons may inflate maximum correlations.Comparisons of different tree-ring proxies,considering varying overlapping period lengths and seasons,revealed 95th percentile correlation differences reaching 0.25 by chance.Using synthetic tree-ring chronologies with an assigned non-signal(r=0.00),spurious correlations can reach statistical significance in over 60%of tests.Correlation inflation is greater when:(1)the climate-proxy relationship is weaker;(2)comparison periods are shorter;and(3)the length of seasonal windows is longer.Autocorrelation in the proxy records does not appear to have a major effect.These findings indicate that caution should be exercised when computing high numbers of correlations with limited observations.We provide tables listing correlation inflations for precipitation-and temperature-sensitive tree-ring chronologies that can inform interpretations of significance.
文摘[目的]分析三峡库区消落带水桦在水淹胁迫下的差异表达基因(DEGs)及关键代谢通路,为阐明水桦抗水淹胁迫的分子机制及消落带苗木选育提供理论依据。[方法]以三峡库区消落带(万州段)栽培的水桦为试验材料,采集水淹约70和200 d的枝条(分别标记为FB70d和FB200d)和根系(分别标记为FR70d和FR200d),并以同期未被水淹的枝条(分别标记为CB70d和CB200d)和根系(分别标记为CR70d和CR200d)为对照,进行转录组测序,筛选CR70d vs FR70d组、CR200d vs FR200d组、CB70d vs FB70d组和CB200d vs FB200d组4个比较组的DEGs,对DEGs进行功能注释及KEGG信号通路富集分析并构建蛋白互作网络。对6个DEGs进行实时荧光定量PCR检测,验证转录组测序数据的可靠性。通过不同浓度乙烯喷施水桦离体枝条研究乙烯对水桦枝条的抗逆影响。[结果]在24个样本中共获得155.99 Gb的有效序列,GC含量为46.00%~48.00%,Q30>92.44%;4个比较组中共筛选出10020个DEGs,其中4389个DEGs上调表达,5631个DEGs下调表达。CB200d vs FB200d组和CB70d vs FB70d组中共有956个DEGs,CR200d vs FR200d组和CR70d vs FR70d组中共有17个DEGs。共有7220个DEGs被注释到生物过程、分子功能和细胞组分三大功能类别上。KEGG信号通路富集分析结果显示,植物激素信号转导通路是DEGs富集最明显的通路。有4个DEGs编码蛋白参与的蛋白调控网络最多。4个比较组中,植物激素信号转导通路共有的基因为35个,其中CR200d vs FR200d组和CB200d vs FB200d组的表达发生改变的基因最多,分别有24和32个。乙烯激活因子基因(ERF1和ERF2)在CB70d vs FB70d组和CB200d vs FB200d组表达上调,而在CR70d vs FR70d组和CR200d vs FR200d组无变化。在ABA生物合成通路中,除CR70d vs FR70d组外,SnRK2基因在其他3个比较组均表达下调。大部分基因的转录组测序结果与实时荧光定量PCR检测结果的变化趋势一致。不同浓度乙烯处理10 d后,与对照相比,3个不同浓度乙烯处理下水桦枝条均能保持幼嫩的生长状态。[结论]水淹后水桦枝条基因对胁迫的响应敏感性高于根系。在植物激素信号转导关键信号通路上,筛选到2个响应水淹胁迫的乙烯激活因子基因(ERF1和ERF2)用于下一步功能验证研究。
基金supported by the Natural Science Foundation of Shanxi Province(202203021221008)the Special Funding for Shanxi Provincial Science and Technology Innovation Talent Team(202204051001010)the National Natural Science Foundation of China(41701047).
文摘In the context of ongoing climate change,rela-tionships between tree growth and climate present uncertain-ties,which limits the predictions of future forest dynamics.Northwest China is a region undergoing notable warming and increased precipitation;how forests in this region will respond to climate change has not been fully understood.We used dendrochronological methods to examine the rela-tionship between climate and the radial growth of four tree species in a riparian forest habitat in Altai region:European aspen(Populus tremula),bitter poplar(Populus laurifolia),Swedish birch(Betula pendula),and Siberian spruce(Picea obovata).The results reveal that European aspen was insen-sitive to climate changes.In contrast,bitter poplar showed a positive response to elevated temperatures and negative to increased moisture during the growing season.Swedish birch and Siberian spruce were adversely affected by higher temperatures but benefited from increased precipitation.A moving correlation analysis suggested that,against a back-drop of continuous warming,growth patterns of these spe-cies will diverge:European aspen will require close moni-toring,bitter poplar may likely to show accelerated growth,and the growth of Swedish birch and Siberian spruce may be inhibited,leading to a decline.These findings offer insight into the future dynamics of riparian forests under changing climate.
