摘要
本文基于树干液流的技术方法,在自然状态下对不同优势等级杨树吸收臭氧特征进行了研究。结果表明：臭氧浓度日变化呈单峰型,其变化范围在25.5~175.0μg/m3之间,臭氧浓度变化趋势与温度变化趋势一致;不同优势等级杨树臭氧吸收速率和臭氧冠层导度日变化均为单峰型;臭氧吸收速率表现为劣势木（43.24 nmol/（m2·s））〉中等木（29.77 nmol/（m2·s））〉优势木（24.56 nmol/（m2·s））,臭氧冠层导度为优势木（101.59 mmol/（m2·s））〉劣势木（92.92 mmol/（m2·s））〉中等木（81.60 mmol/（m2·s））。不同优势等级臭氧吸收速率均值为（32.52±7.87）nmol/（m2·s）,臭氧冠层导度均值为（92.04±8.18）mmol/（m2·s）。不同优势等级太阳辐射、水汽压亏缺和温度对臭氧冠层导度和臭氧吸收速率的影响均表现为优势木〉劣势木〉中等木。臭氧浓度的峰值滞后于液流密度的峰值,过高的臭氧浓度会抑制树木蒸腾,大气臭氧浓度变化和树干液流密度具有较好的一致性,树干液流技术适用于计算植物的臭氧吸收量。
The ozone uptake characteristics of poplar under natural conditions in different dominance hierarchies were studied based on sap flow methods. The results showed that： the diurnal variation of ozone concentration was of single peak type,with the value ranging between 25. 5 and 175. 0 μg / m3; the tendency of its variation was consistent with that of temperature; the diurnal variations of the ozone uptake rate（ F O3） and canopy ozone conductance（ G O3） in different tree shape levels were of unimodal type; the change of F O3 followed an order of depressed tree（ 43. 24 nmol /（ m2·s））〉middle tree（ 29. 77 nmol/（ m2·s））〉dominant tree（ 24. 56 nmol/（ m2·s））,while the value of G O3 ranked as the dominant tree（ 101. 59 mmol/（ m2·s）） depressed tree（ 92. 92 mmol/（ m2·s））〉middle tree（ 81. 60 mmol/（ m2·s））. The mean value of F O3was（ 32. 52 ± 7. 87） nmol /（ m2·s）,while that of G O3was（ 92. 04 ± 8. 18）mmol /（ m2·s） in different tree shape levels. The effects of R s,VPD and t on G O3 and F O3 were in an order of dominant tree depressed tree middle tree. Peak concentrations of ozone lagged behind the peak value of sap flow density,and over-high ozone concentration would inhibit transpiration. There was a good consistency between the changes of atmospheric ozone concentration and sap flow density,and sap flow technique is suitable for the calculation of ozone uptake of plants.
出处
《北京林业大学学报》
CAS
CSCD
北大核心
2015年第7期29-36,共8页
Journal of Beijing Forestry University
基金
北京市优秀人才个人项目(2012D002020000003)
关键词
优势等级
杨树
臭氧吸收
冠层导度
dominance hierarchy
poplar
ozone uptake
canopy conductance
