不同林龄新银合欢重吸收率及其C:N:P化学计量特征  

Nutrient resorption efficiency and C:N:P stoichiometry in different ages of Leucaena leucocephala

作　　者：邓浩俊 陈爱民[1] 严思维 林勇明[1] 张广帅[1] 杜锟 吴承祯[1,2] 洪伟[1] 

机构地区：[1]福建农林大学林学院,福州350002 [2]武夷学院生态与资源工程学院,南平354300

出　　处：《应用与环境生物学报》2015年第3期522-527,共6页Chinese Journal of Applied and Environmental Biology

基　　金：国家自然科学基金项目(41201564);福建农林大学林学院青年科研基金项目(6112C039Q)资助~~

摘　　要：以干热河谷区9、15、26年生新银合欢(Leucaena leucocephala)为研究对象,运用单因素方差分析和Pearson相关性分析,测定并计算其鲜叶、凋落叶的养分含量、重吸收率及其C:N:P化学计量比.结果显示:新银合欢鲜叶N、P含量均表现为15年生>26年生>9年生,凋落叶N、P含量随林龄增加而增大;N、P重吸收率随林龄增大而下降,N、P重吸收率分别在42.76%-55.90%和26.35%-40.60%之间,N重吸收率均大于P重吸收率;鲜叶C:N、C:P均小于凋落叶,但鲜叶N:P大于凋落叶,且N:P均大于20;N重吸收率除与凋落叶N:P无显著相关性外,与其他化学计量比均呈显著正相关(P<0.05);P重吸收率除与凋落叶C:N、C:P有极显著正相关外(P<0.01),与其他化学计量比无显著相关性.本研究表明,干热河谷区新银合欢养分重吸收率表现出随林龄的增大呈下降的趋势,说明新银合欢保存养分的能力随林龄增大而下降;而新银合欢在生长过程中主要受P限制.This research studied the leaf nutrient content before and after senescing, nutrient resorption efficiency （RE） and C：N：P stoichiometry of 9, 15 and 26 years Leueaena leueoeephala in hot and dry valley, using one way analysis of variance and Pearson correlation analysis. The results showed the leaf nitrogen （N） and phosphorus （P） content in an order of 15 a 〉 26 a 〉 9 a, and an increase of N and P content of litter along with the forest age. N and P resorption efficiency （42.76-55.90% and 26.35-40.60% respectively） decreased with the forest age, with the N resorption efficiency greater than P resorption efficiency. Leaf C：N and C：P were less than that of litter, but leaf N：P was greater than that of litter and both of them bigger than 20. Except the N：P of litter, N resorption efficiency was significantly and positively correlated to other stoichiometric ratio, while P resorption efficiency was significantly and positively correlated only to C：N and C：P of the litter. On the whole, the nutrient resorption efficiency of Leucaena leueocephala decreased along with forest age in the hot and dry valley, indicating that the ability of nutrient conservation decreases with the forest age. Besides, we also found that P is the main limiting factor ofLeucaena leueoeephala growing.

关 键 词：干热河谷 新银合欢 鲜叶 凋落叶 重吸收率 化学计量特征 

分 类 号：S792.99[农业科学—林木遗传育种]