Intra-annual growth and its response to climatic factors in four ring-porous wood species
[Objective]The radial growth dynamics of xylem is considered one of the indicators of sensitivity to environmental change.Investigating the xylem formation is crucial to elucidate the relationship between trees growth and the climate.[Method]Microcore sampling and paraffin sections technology were used to monitor the intra-annual growth dynamics of xylem formation.We collected the microcores of Catalpa bungei,Cinnamomum camphora,Fraxinus chinensis and Koelreuteria paniculata every 7-10 d,and Gompertz model was used to fit the modeled value of cumulative radial growth.[Result](1)Cambial activity began in early March and ended in mid-October.The duration of cambial activity was shortest for C.bungei[(189.0±14.6)d],and longest for C.camphora[(216.0±17.4)d].(2)Four species finished the xylem differentiation in early November,and their maximum growth rate occurred in the middle of May.However,the widths of cumulative radial growth showed great variations among four ring-porous species which were from(5 807.0±2 192.9)μm for F.chinensis to(8 276.0±1 744.2)μm for C.bungei.(3)Additionally,temperature may be the main climatic factor influence the radial growth in study area.Both air temperature and surface ground temperature had a significantly positive correlation on the xylem growth increment for four ring-porous wood species(P＜0.01).The positive correlation between precipitation and xylem growth was only in C.camphora(P＜0.05).It may explained by the smallest diameter and area of vessel of C.camphora,which led to the trees were more sensitive to precipitation.[Conclusion]The radial growth of the four tree species in the local area is highly significantly positively correlated with air temperature.The response of the C.camphora plants to climatic factors is stronger than the other three ring-porous porous tree species.[Ch,5 fig.4 tab.52 ref.]
万方数据
维普
