Dendroclimatology method was used to study the relationship between ring index of Pinus massoniana and three climate factors in Dinghushan, South China. The ring indices were negatively correlated with the average tem...Dendroclimatology method was used to study the relationship between ring index of Pinus massoniana and three climate factors in Dinghushan, South China. The ring indices were negatively correlated with the average temperature in June, August and September, and positively correlated with the average temperature of March, whereas no statistically significant correlation was found with monthly precipitation, showing that high summer temperature could limit the radial growth of the species. Meanwhile, tree ring indices showed a strong positive correlation with the relative humidity of April, June, August, September, October and November, and also with the average humidity of the whole year, indicating that atmospheric moisture could not fully satisfy the growth of Pinus massoniana despite of abundant rainfall. The possible impact of climate change on the growth of Pinus massoniana was discussed accordingly.展开更多
Based on the experimental results from seven subtropical species,in contrast with other researchers′ results, the parameter Ci/Ca (ratio of substomatal CO 2 to atmospheric CO 2 concentration)is not stable,but varies ...Based on the experimental results from seven subtropical species,in contrast with other researchers′ results, the parameter Ci/Ca (ratio of substomatal CO 2 to atmospheric CO 2 concentration)is not stable,but varies with species and environmental factors,especially light intensity.Thus,we concluded that the use of tree ring isotope ratios in the reconstruction of atmospheric CO 2 isotope ratio δa variation,which is based on the assumption that Ci/Ca keeps stable during assimilation,is not reliable under current circumstances.展开更多
The concentrations of the elements in the annual rings of Pinus massoniana reflect the influence of both regional factors and species characteristics in absorbing,accumulating and distributing elements.The changes of ...The concentrations of the elements in the annual rings of Pinus massoniana reflect the influence of both regional factors and species characteristics in absorbing,accumulating and distributing elements.The changes of environmental factors may result in concentration changes of elements in tree rings.Therefore,variations of tree ring element concentration may provide some clue in studying environmental changes.Some of eight elements studied are strongly correlated with others,the reason of which might be their similar structural and enzymatic functions in the plant cell,similar chemical properties and similar or opposite reaction to variations in some environment factors.展开更多
文摘Dendroclimatology method was used to study the relationship between ring index of Pinus massoniana and three climate factors in Dinghushan, South China. The ring indices were negatively correlated with the average temperature in June, August and September, and positively correlated with the average temperature of March, whereas no statistically significant correlation was found with monthly precipitation, showing that high summer temperature could limit the radial growth of the species. Meanwhile, tree ring indices showed a strong positive correlation with the relative humidity of April, June, August, September, October and November, and also with the average humidity of the whole year, indicating that atmospheric moisture could not fully satisfy the growth of Pinus massoniana despite of abundant rainfall. The possible impact of climate change on the growth of Pinus massoniana was discussed accordingly.
文摘Based on the experimental results from seven subtropical species,in contrast with other researchers′ results, the parameter Ci/Ca (ratio of substomatal CO 2 to atmospheric CO 2 concentration)is not stable,but varies with species and environmental factors,especially light intensity.Thus,we concluded that the use of tree ring isotope ratios in the reconstruction of atmospheric CO 2 isotope ratio δa variation,which is based on the assumption that Ci/Ca keeps stable during assimilation,is not reliable under current circumstances.
文摘The concentrations of the elements in the annual rings of Pinus massoniana reflect the influence of both regional factors and species characteristics in absorbing,accumulating and distributing elements.The changes of environmental factors may result in concentration changes of elements in tree rings.Therefore,variations of tree ring element concentration may provide some clue in studying environmental changes.Some of eight elements studied are strongly correlated with others,the reason of which might be their similar structural and enzymatic functions in the plant cell,similar chemical properties and similar or opposite reaction to variations in some environment factors.
