亚热带21个树种人工林功能性状与凋落物养分归还特征的关系  

Relationships between functional traits and litterfall nutrient return characteristics across 21 tree species in subtropical plantations

作　　者：林晓瑜 万晓华[1,2] 贾辉 黄志群[1,2] 邹秉章 王思荣 LIN Xiaoyu;WAN Xiaohua;JIA Hui;HUANG Zhiqun;ZOU Bingzhang;WANG Sirong(School of Geographical Sciences,Fujian Normal University,Fuzhou 350117,China;Key Laboratory for Humid Subtropical Eco-Geographical Processes of Ministry of Education,Fujian Normal University,Fuzhou 350117,China;Fujian Shanghang Baisha Forestry Farm,Shanghang 364205,Fujian,China)

机构地区：[1]福建师范大学地理科学学院,福州350117 [2]福建师范大学湿润亚热带生态-地理过程教育部重点实验室,福州350117 [3]福建省上杭白砂国有林场,福建上杭364205

出　　处：《应用生态学报》2024年第6期1455-1462,共8页Chinese Journal of Applied Ecology

基　　金：国家自然科学基金重点项目(31930077,32271842)资助。

摘　　要：森林凋落物的养分归还对于维持土壤碳库和养分循环起至关重要的作用。本研究以亚热带人工幼林的21个树种为对象,分析各树种的叶片和根系功能性状与凋落物养分归还特征的关系。结果表明:不同树种的凋落物量、现存量与养分归还量差异显著,其中米老排的年凋落物量(689.2 g·m^(-2)·a^(-1))和现存量(605.1 g·m^(-2))最高,柳杉的年凋落物量(36.0 g·m^(-2)·a^(-1))和现存量(10.0 g·m^(-2))最低。21个树种的氮归还量为3.0~48.3 kg·hm^(-2),其中最高为闽粤栲;21个树种的磷归还量为0.1~2.0 kg·hm^(-2),最高为枫香。氮、磷归还量最低的树种均为柳杉。逐步回归分析显示,叶片氮含量和叶片干物质含量对凋落物量有显著的负影响,细根组织密度对凋落物量有显著的正影响;叶片氮含量、叶片干物质含量和比根长对现存量有显著的负影响。结构方程模型显示,具有较高叶片干物质含量的树种直接或间接地通过降低凋落物产量来减少氮归还量,而具有较高细根组织密度的树种通过显著增加凋落叶氮含量从而增加氮归还量;具有较高叶片氮含量和叶片干物质含量的树种直接或间接地通过降低凋落物产量从而减少磷归还量。在亚热带营造人工林时,要考虑叶干物质含量低、细根组织密度大的树种,以提高林地凋落物产量和氮、磷养分归还量,进而提高土壤肥力和林地生产力。The contribution of litterfall nutrient return to the maintenance of soil carbon pool and nutrient cycling is a crucial aspect of forest ecosystem functioning.Taking 21 tree species in subtropical young plantations as subjects,we investigated the correlation between litterfall nutrient return characteristics and functional traits of leaf and root and.The results showed notable variations in litterfall production,standing crop,and nutrient return across all the examined tree species.Mytilaria laosensis exhibited the highest litterfall production(689.2 g·m^(-2)·a^(-1))and standing crop(605.1 g·m^(-2)),while Cryptomeria fortunei demonstrated the lowest litterfall production(36.0 g·m^(-2)·a^(-1))and standing crop(10.0 g·m^(-2)).The nitrogen and phosphorus return amounts of 21 species ranged from 3.0 to 48.3 kg·hm^(-2)and from 0.1 to 2.0 kg·hm^(-2),respectively.Castanopsis fissa demonstrated the highest nitrogen return,while Liquidambar formosana exhibited the highest phosphorus return.C.fortunei had the lowest nitrogen and phosphorus return.Results of the stepwise regression analysis indicated that litterfall production exhibited a significant negative correlation with leaf nitrogen content and leaf dry matter content,and a significant positive correlation with fine root tissue density.Additionally,leaf nitrogen content,leaf dry matter content,and specific root length had a significant negative impact on standing crop.The structural equation modelling results indicated that leaf dry matter content had a direct or indirect negative effect on nitrogen return amount through the reduction of litterfall production.Conversely,fine root tissue density had a significant positive impact on nitrogen return amount by increasing litter leaf nitrogen content.Both leaf nitrogen content and leaf dry matter content had direct or indirect negative effects on phosphorus return amount through the reduction of litterfall production.In conclusion,the tree species with low leaf nitrogen content and dry matter content,as well as hi

关 键 词：人工林 养分归还 功能性状 凋落物 土壤肥力 

分 类 号：S714[农业科学—林学]