生态学杂志2017，Vol.36Issue(7)：1769-1776,8.DOI:10.13292/j.1000-4890.201707.037
CO2浓度升高对4种乔木幼树水力结构的影响
Influences of elevated CO2 concentration on hydraulic architecture of seedlings of 4 tree species
摘要
Abstract
Hydraulic architecture parameters with relative ramification rate and in different area stem segments under ambient and elevated CO2 concentrations were measured by improved flushing method.The aims were to study the change of hydraulic architecture,hydraulic safety and efficiency under elevated CO2 concentration.Saplings of four tree species (Pinus tabuliformis,Platycladus orientalis,Acer truncatum and Robinia pseudoacacia) had been exposed to ambient and elevated CO2 concentration for 13 months.The results showed that xylem specific conductivity (Ks) and leaf specific conductivity (LSC) increased in all the ramifications under elevated CO2 concentration.However,the percent loss of hydraulic conductivity (PLC) decreased in P.orientalis and R.pseudoacacia in all the ramifications,and PLC only decreased in branch 2 of P.tabuliformis and in branch 0 and 1 of A.truncatum.Ks increased and PLC decreased in branch 2 of P.tabuliformis and R.pseudoacacia.In P.orientalis,P.tabuliformis and R.pseudoacacia,Ks increased by 12.8％,19.6％ and 51.24％ in branch 2 whereas PLC decreased by 11.80％,9.6％ and 51.01％ under elevated CO2 concentration,respectively.The hydraulic conductivity (Kh) of P.tabuliformis and P.orientalis in the non-restricted area were respectively larger than that in the restricted area,whereas Kh of A.truncatum and R.pseudoacacia were respectively smaller than that in the restricted area.However,the PLC was not significantly affected by elevated CO2 concentration.Ks and LSC of P.orientalis and A.truncatum in the non-restricted area were respectively larger than those in the restricted area,whereas Ks and LSC of P.tabuliformis and R.pseudoacacia were respectively smaller than those in the restricted area.Under elevated CO2 concentration,four tree species with relative ramification showed different strategies to adapt to the changed environment.The strategies included:increasing hydraulic safety and hydraulic efficiency,and decreasing hydraulic security to tradeoff the hydraulic efficiency.However,four tree species in different area stem segments showed different strategies,keeping higher hydraulic efficiency to adapt to the elevated CO2 concentration.关键词
CO2浓度增加/导水率/比导率/叶比导率/安全性/有效性Key words
elevated CO2 concentration/hydraulic conductivity/specific conductivity/leaf specific conductivity/hydraulic safety/hydraulic efficiency引用本文复制引用
刘娟娟,张建国,李吉跃,查巍巍..CO2浓度升高对4种乔木幼树水力结构的影响[J].生态学杂志,2017,36(7):1769-1776,8.基金项目
国家自然科学基金项目(30471370)资助. （30471370）
