滨海沙地3种防护林树种不同季节叶绿素荧光参数日动态及季相变化

Diurnal and Seasonal Changes of Chlorophyll Fluorescence Parameters of Three Shelterbelts in Sandy Coastal Plain Areas

为评估滨海沙地木麻黄、湿地松和尾巨桉对滨海沙地气候环境的适应性,对这3种防护林树种不同季节叶绿素荧光参数日动态及季相变化进行研究。结果表明,一天中,木麻黄的初始荧光(F_o)最低,湿地松的PSⅡ最大光能转换效率(F_v/F_m)和潜在活性(F_v/F_o)均最低,且都不受季节影响。一年四季中,3种防护林树种的最大荧光(F_m)均表现为尾巨桉>湿地松>木麻黄,且季相变化均呈单峰变化规律,木麻黄的F_o、F_m均最小,尾巨桉的F_m、F_v均最大,湿地松的F_v/F_m、F_v/F_o均最小,表明湿地松开放的PSⅡ反应中心的光量捕捉效率低于木麻黄和尾巨桉。结合林分生长情况可知湿地松受环境胁迫,对滨海沙地环境的适应能力较木麻黄和尾巨桉差。

In order to evaluate the adaptability of Casuarina equisetifolia,Pinus elliottii and Eucalyptus urophylla×E.grandis to the climate of coastal sand environment,we investigated the diurnal and seasonal changes of chlorophyll fluorescence parameters of three shelterbelt construction species.The results showed that,in one day,the initial fluorescence(F o)of C.equisetifolia was the lowest,the maximum energy conversion efficiency(F v/F m)and potential activity(F v/F o)of PSⅡof P.elliottii were the lowest,and they were not affected by the season.In the four seasons of a year,the values of the maximum fluorescence(F m)of the three species were all characterized by E.urophylla×E.grandis>P.elliottii>C.equisetifolia,and the seasonal changes showed a unimodal variation.The F o and F m of C.equisetifolia were the lowest,and the F m and F v of E.urophylla×E.grandis were the highest,and the F v/F m and F v/F o of P.elliottii were the lowest.It was indicated that P.elliottii s energy capture efficiency of opening PSⅡreaction center was lower than that in C.equisetifolia and E.urophylla×E.grandis.It was known that P.elliottii was subjected to environmental stress according to the growth of stand,and its adaptability to the coastal sandy environment was less than those of C.equisetifolia and E.urophylla×E.grandis.