文献类型：期刊文献

中文题名：CO_2浓度升高对4种乔木幼树水力结构的影响

英文题名：Influences of elevated CO_2 concentration on hydraulic architecture of seedlings of 4 tree species

作者：刘娟娟[1] 张建国[1] 李吉跃[2] 查巍巍[1]

第一作者：刘娟娟

机构：[1]中国林业科学研究院林业研究所国家林业局林木培育重点实验室;[2]华南农业大学林学院

年份：2017

卷号：36

期号：7

起止页码：1769-1776

中文期刊名：生态学杂志

外文期刊名：Chinese Journal of Ecology

收录：CSTPCD;;Scopus;北大核心:【北大核心2014】；CSCD:【CSCD2017_2018】；

基金：国家自然科学基金项目(30471370)资助

语种：中文

中文关键词：CO2浓度增加;导水率;比导率;叶比导率;安全性;有效性

外文关键词：elevated CO2 concentration ; hydraulic conductivity ; specific conductivity ; leaf spe-cific conductivity; hydraulic safety; hydraulic efficiency.

分类号：S512.12

摘要：以油松(Pinus tabuliformis)、侧柏(Platycladus orientalis)、元宝枫(Acer truncatum)和刺槐(Robinia pseudoacacia)幼树为研究对象,采用改良冲洗法测定不同分枝级和茎段所在区域的水力结构参数,研究CO_2浓度升高对4个树种水力结构及水分运输安全性和有效性的影响。结果表明:CO_2浓度升高,4个树种在3个分枝级(0、1和2级分枝)的比导率(Ks)和叶比导率(LSC)增加,而侧柏和刺槐在3个分枝的导水率损失(PLC)均下降,油松2级和元宝枫0和1级分枝的PLC下降,其中2级分枝的参数变化最为显著,侧柏、油松和刺槐2级分枝的Ks升高了12.8%、19.6%和51.24%,PLC下降了11.80%、9.6%和51.01%,而元宝枫2级分枝的Ks和PLC均升高。CO_2浓度升高对油松和侧柏非限速区的导水率(Kh)的提高大于限速区,元宝枫和刺槐则相反,而PLC不受CO_2浓度升高的影响。高CO_2浓度对侧柏和元宝枫提高非限速区Ks和LSC大于限速区,油松和刺槐则相反。4个树种在不同分枝级采取不同的方式来适应CO_2浓度的升高,采取的生态策略包括:保持较高的水分运输有效性,同时提高有效性和安全性,和减轻安全性而对有效性的折衷;而在不同茎段所在区域采取保持较高的水分运输效率来适应大气CO_2浓度的升高。
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.