Polylepis(Queñua)is a dominant woody plant genus in Andean Puna forests that occurs in a wide range of montane habitats and is ecologically diverse in endemism,which may be particularly threatened by climate chan...Polylepis(Queñua)is a dominant woody plant genus in Andean Puna forests that occurs in a wide range of montane habitats and is ecologically diverse in endemism,which may be particularly threatened by climate change.Wood anatomical traits are essential for understanding how plants adjust their ecophysiological requirements and maximize their resilience,resistance,and recovery to extreme climates.Although the effects of extreme climatic conditions in high altitude ecosystems have been studied extensively,our knowledge is relatively limited to quantitative differences in the main xylem tissues.To address this gap,we assessed the acclimation of wood anatomical traits in six Peruvian Andean Polylepis species with different water availability(semi-dry with high moisture and semiarid with dry winters).We selected hydraulic diameter,vessel density,vessel grouping index,solitary vessel index,vulnerability index,mesomorphy index,vessel element length,fiber length,fiber wall thickness,fiber lumen diameter,and total fiber diameter that can provide relevant eco-wood anatomical acclimation to hydric stress.We performed multivariate analysis to determine the leading dimensions of covariation among Polylepis species and climatic factors.Specific wood anatomical traits(vessel grouping index,vulnerability index,and fiber wall thickness)were dissimilar between xeric-and mesic-Polyelpis species.This study demonstrates that wood anatomical traits in Peruvian Andean Polylepis species provides high-resolution and long-term eco-wood anatomical signals on how climate oscillations drive the acclimation processes of fiber and vessel traits.Our findings underscore the significance of xylem hydraulic adjustment to various hydrological environments in Andean puna forests.By evaluating the effects of drought on wood anatomical characteristics and ecological function,we demonstrate the capacity of tree species to adapt and endure climate-related changes,thereby emphasizing their resilience and adaptability.展开更多
We tested the hypothesis that the biometrical characters of wood elements in ash trees(Fraxinus excelsior L.) become modified in response to the progression of disease caused by Chalara fraxinea. Anatomical analyses w...We tested the hypothesis that the biometrical characters of wood elements in ash trees(Fraxinus excelsior L.) become modified in response to the progression of disease caused by Chalara fraxinea. Anatomical analyses were performed on wood samples collected at breast height from the trunks of groups of ash trees which contained healthy, weakened and dead trees. We measured(1) treering width,(2) earlywood vessel diameter,(3) earlywood vessel element length,(4) fibre length,(5) fibre diameter,(6) fibre lumen diameter, and(7) fibre wall thickness. We showed that tree-ring width diminished in all analysed groups during disease progression. However, the greatest suppression of growth was observed in dead trees. In both weakened and dead ash trees, the reduction in tree-ring width was accompanied by diminished vessel diameter in the earlywood of the outermost annual rings. The annual rings of dead trees had shorter fibres having greater lumen diameter and thinner cell walls. Consequently, water conduction in the sapwood of dead ash trees was less efficient owing to reduced vessel diameter, and this seems to be one of the greatest disease-induced morphological modifications. All the anatomical modifications might be due to leaf loss and crown dieback triggered by Chalara fraxinea.展开更多
基金The authors are very grateful to park ranger the RPNYC,Eber Melgar Guerra Almerco for his support in sample collection and Cassiana Alves-Ferreira for his support in the Laboratorio de Anatomía e Identificación de Maderas,Universidad Continentalpartial funding provided by EJ Requena-Rojas and M Morales(047-2015-Fondecyt-DE and CONICET PIP 11220130100584 project)。
文摘Polylepis(Queñua)is a dominant woody plant genus in Andean Puna forests that occurs in a wide range of montane habitats and is ecologically diverse in endemism,which may be particularly threatened by climate change.Wood anatomical traits are essential for understanding how plants adjust their ecophysiological requirements and maximize their resilience,resistance,and recovery to extreme climates.Although the effects of extreme climatic conditions in high altitude ecosystems have been studied extensively,our knowledge is relatively limited to quantitative differences in the main xylem tissues.To address this gap,we assessed the acclimation of wood anatomical traits in six Peruvian Andean Polylepis species with different water availability(semi-dry with high moisture and semiarid with dry winters).We selected hydraulic diameter,vessel density,vessel grouping index,solitary vessel index,vulnerability index,mesomorphy index,vessel element length,fiber length,fiber wall thickness,fiber lumen diameter,and total fiber diameter that can provide relevant eco-wood anatomical acclimation to hydric stress.We performed multivariate analysis to determine the leading dimensions of covariation among Polylepis species and climatic factors.Specific wood anatomical traits(vessel grouping index,vulnerability index,and fiber wall thickness)were dissimilar between xeric-and mesic-Polyelpis species.This study demonstrates that wood anatomical traits in Peruvian Andean Polylepis species provides high-resolution and long-term eco-wood anatomical signals on how climate oscillations drive the acclimation processes of fiber and vessel traits.Our findings underscore the significance of xylem hydraulic adjustment to various hydrological environments in Andean puna forests.By evaluating the effects of drought on wood anatomical characteristics and ecological function,we demonstrate the capacity of tree species to adapt and endure climate-related changes,thereby emphasizing their resilience and adaptability.
基金partly supported by Grant No.NN309 077438 from the Ministry of Science and Higher Education
文摘We tested the hypothesis that the biometrical characters of wood elements in ash trees(Fraxinus excelsior L.) become modified in response to the progression of disease caused by Chalara fraxinea. Anatomical analyses were performed on wood samples collected at breast height from the trunks of groups of ash trees which contained healthy, weakened and dead trees. We measured(1) treering width,(2) earlywood vessel diameter,(3) earlywood vessel element length,(4) fibre length,(5) fibre diameter,(6) fibre lumen diameter, and(7) fibre wall thickness. We showed that tree-ring width diminished in all analysed groups during disease progression. However, the greatest suppression of growth was observed in dead trees. In both weakened and dead ash trees, the reduction in tree-ring width was accompanied by diminished vessel diameter in the earlywood of the outermost annual rings. The annual rings of dead trees had shorter fibres having greater lumen diameter and thinner cell walls. Consequently, water conduction in the sapwood of dead ash trees was less efficient owing to reduced vessel diameter, and this seems to be one of the greatest disease-induced morphological modifications. All the anatomical modifications might be due to leaf loss and crown dieback triggered by Chalara fraxinea.