论文部分内容阅读
近地层臭氧(O3)浓度升高会降低树木的光合速率,抑制Rubisco酶的活性,势必会间接影响树木N素的吸收与分配.本研究利用开顶式气室研究过滤大气(CF,<20 nL·L-1)与O3浓度升高(E-O3,约150 nL·L-1)对10种南方城市常用绿化树种幼苗N素吸收和分配的影响.结果表明,与CF相比,E-O3使枫香叶生物量和马褂木茎生物量分别显著降低了20.9%和21.4%,使枫香和马褂木的根生物量显著降低了24.2%和32.5%.O3对被测树种茎中N素含量影响显著,而对叶和根中N素含量无显著影响.O3对被测树种整株树N素吸收总量(Ntu)、叶片N素吸收量及根的N素吸收量存在显著影响,而对茎N素吸收量无显著影响.与CF相比,E-O3使马褂木与木荷的Ntu分别显著降低了28.4%与22.7%,而使舟山新木姜子Ntu显著增加了15.5%.O3浓度升高对各树种N素吸收量在各器官中的分配无显著影响.
The increase of O3 concentration in the near-field will decrease the photosynthetic rate of trees and inhibit the activity of Rubisco, which will indirectly affect the absorption and distribution of N in the tree.In this study, (E-O3, about 150 nL·L-1) on N uptake and distribution of seedlings in common greening tree species in 10 southern Chinese cities were studied.The results showed that compared with CF, E -O3 significantly decreased the biomass of Maple Leaves and Pinus massoniana by 20.9% and 21.4%, respectively, and significantly reduced the root biomass of Liquidambar formosana and Liriodendron by 24.2% and 32.5%, respectively. N content was significantly affected, while there was no significant effect on N content in leaves and roots.O3 had significant effects on Ntu, N absorption and N uptake of roots of the tested tree species , But had no significant effect on the uptake of stem N. Compared with CF, E-O3 significantly decreased the Ntu of P. xylophilus and M. jacker by 28.4% and 22.7%, respectively, and significantly increased Ntu 15.5% .O3 concentration had no significant effect on the N-uptake of each species in each organ.