林窗大小对马尾松人工林更新植物生态化学计量特征的影响  

Effects of forest gap size on ecological stoichiometric characteristics of update plants in Pinus massoniana plantation

作　　者：宋思梦 谭波[1,2] 周扬[1] 张健[1,2] 李艳[1] 姚小兰[1] 李相君[1] 李亚洲[1] 陈凯[1] 李柏翰 

机构地区：[1]四川农业大学生态林业研究所、华西雨屏区生态环境监测站,成都611130 [2]四川省长江上游生态安全协同创新中心,成都611130

出　　处：《应用与环境生物学报》2016年第6期1040-1047,共8页Chinese Journal of Applied and Environmental Biology

基　　金：国家科技支撑计划项目(2011BAC09B05);国家自然科学基金项目(31370628);四川省科技支撑计划项目(12ZC0017);四川省科技厅应用基础项目(2012JY0047);四川省教育厅科技创新团队计划项(11TD006);四川省大学生创新训练计划项目(201410626032)资助~~

摘　　要：为了解林窗大小对马尾松人工林林窗下更新过程中优势植物生态化学计量特征的影响,在长江上游低山丘陵区选取7种面积不等(100 m^2、225 m^2、400 m^2、625 m^2、900 m^2、1 225 m^2、1 600 m^2)的人为采伐形成的林窗,以林下为对照,分析更新优势植物油樟、芒萁、芒和皱叶狗尾草叶片化学计量特征.结果表明:4种植物化学计量特征对林窗大小响应不同,在各自林窗梯度中均有显著差异.4种植物C:N为17.0-37.7,C:P为152.5-748.0,N:P为6.4-21.5.随林窗面积增大,油樟、芒和皱叶狗尾草C:N均先升后降,C:P和N:P先降后升,芒萁变化不明显.油樟C、N、P元素分配最佳的林窗为625 m^2,芒萁为1 225 m^2,芒和皱叶狗尾草为1 600 m^2.4种植物在多数林窗中不受N、P限制,但900 m^2林窗中油樟和芒萁均处于缺P状态,400 m^2林窗中芒和皱叶狗尾草均受N限制.综上,更新油樟树种采用625 m^2林窗表现出较理想的效果,芒萁、芒和皱叶狗尾草的自然更新则在大面积林窗(1 225-1 600 m^2)中效果更好.Plant ecological stoichiometry is an important way to investigate the material cycling and energy flow between plants and the environment, which can be modulated during forest regeneration by artificial factors such as forest gap. This study aimed to understand the effects of artificial forest gap of different sizes on the ecological stoichiometry of update dominant plants in Pinus Massoniana plantation. The ecological stoichiometric characteristics of four dominant update species （Cinnamomum longepaniculatum, Dicranopteris dichotoma, Miscanthus sinensis and Setaria plicata） were observed in seven gaps （GI： 100 m2; G2：225 m2; G3：400 m2; G4：625 m2; G5：900 m2; G6：1 225 m2; G7：1 600 m2; closed canopy as the control） in a 39-year-old masson pine （P. Massoniana） plantation in the upper reaches of the Yangtze River. The results showed significant effects of the forest gap size on the ecological stoichiometry in all four species but with different patterns. The ratios ofC ： N, C ： P and N ： P for the tested species ranged from 17.0 to 37.7, 152.5 to 748.0, 6.4 to 21.5, respectively. With the increase of the area of forest gap, the C ： N ratio in C. longepaniculatum, M. sinensis and S. plicata first increased and then decreased, but the C ： P and N ： P ratios first declined and then rose. The ecological stoichiometry of D. dichotoma did not vary significantly with the forest gap. The best forest gap allocation of carbon, nitrogen and phosphorus was 625 m2 for C. longepaniculatum, 1 225 m2 for D. dichotoma, and 1 600 m2 for M. sinensis and S. plicata. The growth of the four dominant update plants was not limited by nitrogen or phosphorus in most of the forest gaps, whereas C. longepanieulatum and D. dichotoma were limited by nitrogen in the 900 m2 forest gap, and M. sinensis and S. plicata restricted by phosphorus in the 400 m2 forest gap. The results indicated that forest gap of 625 m2 is suitable for C. Iongepaniculatum, whereas D. dichotoma, M.sinensis and S. plicata need larger fo

关 键 词：林窗大小 马尾松人工林 生态化学计量特征 更新植物 养分利用率 

分 类 号：S718.5[农业科学—林学]