[Objectives]This study aimed to select evergreen broad-leaved woody plants with higher ornamental value and stronger cold tolerance for introduction from the south to the north,and to apply them to urban greening,so a...[Objectives]This study aimed to select evergreen broad-leaved woody plants with higher ornamental value and stronger cold tolerance for introduction from the south to the north,and to apply them to urban greening,so as to enrich the plant community structure of the landscape in the northern region.[Methods]Three species of evergreen broad-leaved woody plants,i.e.,Ligustrum lucidum,Ilex cornuta and Eriobotrya japonica,were selected as the experimental materials.The morphological performances and the changes of the physiological indexes were observed and measured during the overwintering period in the open field in Beijing.The relationship between the indexes and the low temperature was also analyzed.The strength of cold tolerance of the three species was compared.[Results]The electrical conductivity,the contents of MDA and proline were negatively correlated with the corresponding low temperature.The contents of soluble sugar and soluble protein increased with the dropping temperature,but they had little response to the short-term temperature rise.[Conclusions]Combined with morphological and physiological indexes,it was found that the changes of the contents of proline and soluble sugar among the physiological indexes were closely related to the cold tolerances of the three tree species of broad-leaved woody plants.The cold tolerance of I.cornuta was the strongest,E.japonica was the second,and that of L.lucidum was the worst.展开更多
In Yingzuijie National Nature Reserve, Pinus massoniana forest, mixed broadleaf-coniferous forest and evergreen broad-leaf forest were investigated to study the changing characteristics of woody debris (WD) during v...In Yingzuijie National Nature Reserve, Pinus massoniana forest, mixed broadleaf-coniferous forest and evergreen broad-leaf forest were investigated to study the changing characteristics of woody debris (WD) during various succession stages o1 evergreen broad-leaf forest. The results showed that during various succession stages of evergreen broad-leaf forest in Yingzuijie National Nature Reserve, WD storage of each forest ranged from 1.26 to 8.82 t/hm^2, with the order of P. massoniana forest 〈 mixed broadleaf-coniferous forest 〈 evergreen broad-leaf forest, that is, it increased from early to late stages of the succession. At different succession stages, coarse woody debris (CWD) storage was 2 -9 times more than fine woody debris (FWD) storage, revealing that CWD was dominant in WD of each forest. CWD biomass accounted for 0.66% -2.21% of arbor biomass, so the forests were at the developmental stage.展开更多
为了解雅鲁藏布大峡谷区域植物的生态适应性及N、P养分利用特征,该研究在墨脱不同森林植被区选取6个采样点,对每个采样点优势植物进行了植物叶片C、N、P化学计量特征分析。结果表明,研究区植物叶片碳含量均值为452 g kg^(-1),在不同采...为了解雅鲁藏布大峡谷区域植物的生态适应性及N、P养分利用特征,该研究在墨脱不同森林植被区选取6个采样点,对每个采样点优势植物进行了植物叶片C、N、P化学计量特征分析。结果表明,研究区植物叶片碳含量均值为452 g kg^(-1),在不同采样点之间差异未达到显著水平,其余指标在部分采样点之间则存在一定的差异;从生活型看,研究区木本植物叶片碳含量要高于草本植物,氮含量差异不显著,磷含量则低于草本植物;在不同采样点之间木本植物叶片碳氮磷含量差异不显著,木本植物碳氮差异也不显著,但草本植物部分采样点之间磷差异达到显著水平;相关性分析显示,植物叶片C与N、C与P相关性均不显著,但N、P相关性达到极显著水平;墨脱常绿阔叶林区植物叶片C含量略低于我国南方其它常绿阔叶林区植物叶片碳含量,氮含量略高于其他区域,但P含量显著高于其他区域的植物叶片P含量,因此C/N,C/P及N/P均较低,N/P的均值为11.4。本研究结果支持植物叶片氮磷在不同生境中均存在明显正相关关系,结合生长速率假说,墨脱常绿阔叶林区的植物生长速率可能远高于我国其他常绿阔叶林区,因此研究区森林生态系统的碳汇以及面对全球N沉降背景下的响应值得进一步研究。展开更多
Understanding biogeographic patterns and the mechanisms underlying them has been a main issue in macroecology and biogeography, and has implications for biodiversity conservation and ecosystem sustainability. Evergree...Understanding biogeographic patterns and the mechanisms underlying them has been a main issue in macroecology and biogeography, and has implications for biodiversity conservation and ecosystem sustainability. Evergreen broad-leaved woody plants(EBWPs) are important components of numerous biomes and are the main contributors to the flora south of 35°N in China. We calculated the grid cell values of species richness(SR) for a total of 6265 EBWP species in China, including its four growth-forms(i.e., tree, shrub, vine, and bamboo), and estimated their phylogenetic structure using the standardized phylogenetic diversity(SPD) and net relatedness index(NRI). Then we linked the three biogeographical patterns that were observed with each single environmental variable representing the current climate, the last glacial maximum(LGM)–present climate variability, and habitat heterogeneity, using ordinary least squares regression with a modified t-test to account for spatial autocorrelation. The partial regression method based on a general linear model was used to decompose the contributions of current and historical environmental factors to the biogeographical patterns observed. The results showed that most regions with high numbers of EBWP species and phylogenetic diversity were distributed in tropical and subtropical mountains with evergreen shrubs extending to Northeast China. Current mean annual precipitation was the best single predictor. Topographic variation and its effect on temperature variation was the best single predictor for SPD and NRI. Partial regression indicated that the current climate dominated the SR patterns of Chinese EBWPs. The effect of paleo-climate variation on SR patterns mostly overlapped with that of the current climate. In contrast, the phylogenetic structure represented by SPD and NRI was constrained by paleo-climate to much larger extents than diversity, which was reflected by the LGM–present climate variation and topog-raphy-derived habitat heterogeneity in China. Our study highlights the importance of embedding multiple dimensions of biodiversity into a temporally hierarchical framework for understanding the biogeographical patterns, and provides important baseline information for predicting shifts in plant diversity under climate change.展开更多
基金Key Project of Beijing Municipal Education CommissionProject of Construction of Advanced Horticulture Under Beijing Municipality(2020)+2 种基金National Natural Science Foundation of China(31201645,31640070)Beijing Municipal Natural Science Foundation(3172006)Project of Construction of Innovative Teams and Teacher Career Development for Universities and Colleges Under Beijing Municipality(IDHT 20150503).
文摘[Objectives]This study aimed to select evergreen broad-leaved woody plants with higher ornamental value and stronger cold tolerance for introduction from the south to the north,and to apply them to urban greening,so as to enrich the plant community structure of the landscape in the northern region.[Methods]Three species of evergreen broad-leaved woody plants,i.e.,Ligustrum lucidum,Ilex cornuta and Eriobotrya japonica,were selected as the experimental materials.The morphological performances and the changes of the physiological indexes were observed and measured during the overwintering period in the open field in Beijing.The relationship between the indexes and the low temperature was also analyzed.The strength of cold tolerance of the three species was compared.[Results]The electrical conductivity,the contents of MDA and proline were negatively correlated with the corresponding low temperature.The contents of soluble sugar and soluble protein increased with the dropping temperature,but they had little response to the short-term temperature rise.[Conclusions]Combined with morphological and physiological indexes,it was found that the changes of the contents of proline and soluble sugar among the physiological indexes were closely related to the cold tolerances of the three tree species of broad-leaved woody plants.The cold tolerance of I.cornuta was the strongest,E.japonica was the second,and that of L.lucidum was the worst.
基金Supported by the International Science and Technology Cooperation Program of China(2011DFA90740)Science and Technology Cooperation Program between Ministry of Science and Technology of China and European Union(0906)+1 种基金Research and Innovation Foundation for Young Scholars of Hunan Academy of Forestry(2013LQJ08)Forestry Science and Technology Program of Hunan Province,China(XLK201417)
文摘In Yingzuijie National Nature Reserve, Pinus massoniana forest, mixed broadleaf-coniferous forest and evergreen broad-leaf forest were investigated to study the changing characteristics of woody debris (WD) during various succession stages o1 evergreen broad-leaf forest. The results showed that during various succession stages of evergreen broad-leaf forest in Yingzuijie National Nature Reserve, WD storage of each forest ranged from 1.26 to 8.82 t/hm^2, with the order of P. massoniana forest 〈 mixed broadleaf-coniferous forest 〈 evergreen broad-leaf forest, that is, it increased from early to late stages of the succession. At different succession stages, coarse woody debris (CWD) storage was 2 -9 times more than fine woody debris (FWD) storage, revealing that CWD was dominant in WD of each forest. CWD biomass accounted for 0.66% -2.21% of arbor biomass, so the forests were at the developmental stage.
文摘为了解雅鲁藏布大峡谷区域植物的生态适应性及N、P养分利用特征,该研究在墨脱不同森林植被区选取6个采样点,对每个采样点优势植物进行了植物叶片C、N、P化学计量特征分析。结果表明,研究区植物叶片碳含量均值为452 g kg^(-1),在不同采样点之间差异未达到显著水平,其余指标在部分采样点之间则存在一定的差异;从生活型看,研究区木本植物叶片碳含量要高于草本植物,氮含量差异不显著,磷含量则低于草本植物;在不同采样点之间木本植物叶片碳氮磷含量差异不显著,木本植物碳氮差异也不显著,但草本植物部分采样点之间磷差异达到显著水平;相关性分析显示,植物叶片C与N、C与P相关性均不显著,但N、P相关性达到极显著水平;墨脱常绿阔叶林区植物叶片C含量略低于我国南方其它常绿阔叶林区植物叶片碳含量,氮含量略高于其他区域,但P含量显著高于其他区域的植物叶片P含量,因此C/N,C/P及N/P均较低,N/P的均值为11.4。本研究结果支持植物叶片氮磷在不同生境中均存在明显正相关关系,结合生长速率假说,墨脱常绿阔叶林区的植物生长速率可能远高于我国其他常绿阔叶林区,因此研究区森林生态系统的碳汇以及面对全球N沉降背景下的响应值得进一步研究。
基金National Natural Science Foundation of China,No.41790425,No.41701055National Key R&D Program of China,No.2017YFC0505200Major Project of the Yunnan Science and Technology Department,No.2018 FY001(-002)
文摘Understanding biogeographic patterns and the mechanisms underlying them has been a main issue in macroecology and biogeography, and has implications for biodiversity conservation and ecosystem sustainability. Evergreen broad-leaved woody plants(EBWPs) are important components of numerous biomes and are the main contributors to the flora south of 35°N in China. We calculated the grid cell values of species richness(SR) for a total of 6265 EBWP species in China, including its four growth-forms(i.e., tree, shrub, vine, and bamboo), and estimated their phylogenetic structure using the standardized phylogenetic diversity(SPD) and net relatedness index(NRI). Then we linked the three biogeographical patterns that were observed with each single environmental variable representing the current climate, the last glacial maximum(LGM)–present climate variability, and habitat heterogeneity, using ordinary least squares regression with a modified t-test to account for spatial autocorrelation. The partial regression method based on a general linear model was used to decompose the contributions of current and historical environmental factors to the biogeographical patterns observed. The results showed that most regions with high numbers of EBWP species and phylogenetic diversity were distributed in tropical and subtropical mountains with evergreen shrubs extending to Northeast China. Current mean annual precipitation was the best single predictor. Topographic variation and its effect on temperature variation was the best single predictor for SPD and NRI. Partial regression indicated that the current climate dominated the SR patterns of Chinese EBWPs. The effect of paleo-climate variation on SR patterns mostly overlapped with that of the current climate. In contrast, the phylogenetic structure represented by SPD and NRI was constrained by paleo-climate to much larger extents than diversity, which was reflected by the LGM–present climate variation and topog-raphy-derived habitat heterogeneity in China. Our study highlights the importance of embedding multiple dimensions of biodiversity into a temporally hierarchical framework for understanding the biogeographical patterns, and provides important baseline information for predicting shifts in plant diversity under climate change.