生态学报2018，Vol.38Issue(11)：4027-4036,10.DOI:10.5846/stxb201707141278
亚热带不同林龄杉木林叶-根-土氮磷化学计量特征
Variation in the N and P stoichiometry of leaf-root-soil during stand development in a Cunninghamia lanceolata plantation in subtropical China
摘要
Abstract
We measured total N and P concentrations of leaf,fine root,and soil (0-15,15-30,30-45 cm) in 5-,10-,15-,20-,and 25-year-old Cunninghamia lanceolata plantations in Huitong,Hunan Province.The objective of this study was to determine the variation in the N and P stoichiometry of leaf-root-soil during the whole life process of Cunninghamia lanceolata plantations,and provide basic data to guide the management of Cunninghamia lanceolata plantations.The following results were obtained.(1) Stand age had a significant influence on soil N and P concentrations and the N ∶P ratio (P ＜ 0.01).Soil layer only had significant influence on soil N concentrations (P ＜ 0.01).Soil N concentrations decreased with increasing soil depth,whereas soil P concentrations and the N ∶P ratio showed no significant difference with increasing soil depth.In each soil layer,N and P concentrations initially decreased and then increased significantly with increasing stand age (P ＜ 0.05).Soil N and P concentrations were the highest in 25-year and 5-year Cunninghamia lanceolata plantations,respectively,and were the lowest in 10-year and 15-year Cunninghamia lanceolata plantations.The soil N ∶P ratio increased with increasing stand age,although not significantly.(2) Stand age and organ type had a significant influence on plant N and P concentrations and the N ∶P ratio (P ＜ 0.01).Leaf and fine root N and P concentrations showed a significant " V-shaped" pattern with increasing stand age (P ＜ 0.05),whereas fine root P decreased slightly in 20-year Cunninghamia lanceolata plantations.Leaf and fine root N and P concentrations were the lowest in 15-year Cunninghamia lanceolata plantations,and were the highest in 5-year and 25-year Cunninghamia lanceolata plantations,respectively.The leaf N ∶P ratio did not change significantly with increasing stand age.The range of leaf N∶P ratios was 11.79 to 14.86.For all stand ages,leaf N∶P ratios were lower than 14,except for 20-year Cunninghamia tanceotata plantations,indicating that N was the main factor limiting the growth of Cunninghamia lanceolata.The fine root N ∶ P ratio increased significantly with increasing stand age (P ＜ 0.05),and the range of fine root N ∶ P ratios was 9.00 to 22.89.(3) During the whole life process of Cunninghamia lanceolata plantations,N and P concentrations were significantly different between leaf,fine root,and soil in the order leaf ＞ fine root ＞ soil (P ＜ 0.05).There were significant correlations between leaf and fine root N and P stoichiometry (P ＜ 0.05),except for the leaf and fine root N of 25-year Cunninghamia lanceolata plantations.However,no significant correlations between 0-15 cm soil and leaf and fine root N concentrations were found.There were significant correlations between 15-30 and 30-45 cm soil and leaf and fine root N and P concentrations in 5-year and 10-year Cunninghamia lanceolata plantations (P ＜ 0.05),whereas there were no significant correlations between soil and leaf and fine root N and P concentrations in 15-,20-,and 25-year-old Cunninghamia lanceolata plantations.During the whole life process of Cunninghamia lanceolata plantations,there were significant correlations between leaf and fine root and soil P concentrations and the N ∶P ratio.It was concluded that with forest development,there have been changes in the nutrients of leaf,fine root,and soil,which reflect the strong links between leaf,fine root,and soil N and P stoichiometry.关键词
叶-根-土/不同林龄/生态化学计量特征/氮/磷/杉木林Key words
leaf-root-soil/different stand age/ecological stoichiometry/nitrogen/phosphorus/Cunninghamia lanceolata plantation引用本文复制引用
陈安娜,王光军,陈婵,李淑英,李维佳..亚热带不同林龄杉木林叶-根-土氮磷化学计量特征[J].生态学报,2018,38(11):4027-4036,10.基金项目
国家自然科学基金项目(31600355) （31600355）
国家林业局软科学研究项目(2016-R33) （2016-R33）
湖南省科技计划项目(2015SK20022) （2015SK20022）
