中亚热带森林转换对地表凋落物现存量及其组分的影响  

Effects of Forest Conversion on the Standing Storage of Litter and Its Components in Mid-Subtropical Region

作　　者：吴捷录 张雪 王宏宇 吴福忠 WU Jielu;ZHANG Xue;WANG Hongyu;WU Fuzhong(Key Laboratory for Humid Subtropical Ecogeographical Processes of the Ministry of Education,School of Geographical Sciences,Fujian Normal University,Fuzhou 350117,China)

机构地区：[1]福建师范大学地理科学学院,湿润亚热带生态—地理过程教育部重点实验室,福建福州350117

出　　处：《福建师范大学学报（自然科学版）》2024年第2期116-124,共9页Journal of Fujian Normal University：Natural Science Edition

基　　金：国家自然科学基金资助项目(32101509,32171641,32271633)。

摘　　要：依托福建三明森林生态系统国家野外观测研究站森林转换研究平台,在凋落物高峰期选择立地条件相对一致的以米槠为建群种的常绿阔叶林、次生林以及米槠人工林为研究对象,调查森林地表凋落物量及其组分(叶、枝、果、其他)与分解程度(未分解层与半分解层),并分析米槠凋落叶的物理性状差异。结果表明:天然林转换为次生林和人工林后凋落物现存量分别显著降低了33.03%和63.19%,凋落叶占总现存量的相对比例分别下降了5.72%和4.85%,但凋落枝和其他部分的相对比例略有上升,改变了地表凋落物的组成格局。天然林转换为次生林后未分解层和半分解层凋落物量分别降低了37.49%和37.08%,相对比例基本不变;但转换为人工林后未分解层和半分解层凋落物量分别降低了51.75%和70.12%,半分解层相对比例下降了11.07%,表明人工林可能具有相对快速的凋落物分解过程。此外,森林转换显著改变了建群种米槠凋落叶的面积、周长等物理性状,其中比叶面积和叶组织密度的变异系数最大。可见,天然林转换后凋落量明显减少,半分解层凋落物量相对于未分解层下降更为明显,不利于森林凋落物归还到土壤,形成土壤有机质。Leveraging the forest conversion research platform at the Fujian Sanming Forest Ecosystem National Observation and Research Station,we selected relatively uniform sites during the peak litterfall period,including natural evergreen broad-leaved forest,secondary forest and Castanopsis carlesii plantation,with Castanopsis carlesii as the constructive species.We investigated the amount and components(leaves,branches,fruits,and others)of forest litter,as well as the decomposition degree(undecomposed layer and semi-decomposed layer),and analyzed the physical traits of Castanopsis carlesii leaf litter.The results showed that the conversion of natural forest to secondary forest led to a significant decrease of 33.03%in litter standing storage,while the conversion to a plantation resulted in a significant decrease of 63.19%.The relative proportion of leaf litter to the total standing storage decreased by 5.72%and 4.85%for secondary forest and plantation,respectively,whereas the relative proportions of twig litter and other parts increased slightly.Moreover,the conversion of natural forest to secondary forest respectively induced a significant decrease of 37.49%and 37.08%in the amount of litter in the undecomposed and semi-decomposed layers,with few significant changes in their relative proportions.However,a significant decrease of 51.75%and 70.12%in the amount of litter in the undecomposed and semi-decomposed layers occurred during the conversion of natural forest to a plantation,respectively.The relative proportion of litter components in the semi-decomposed layer decreased by 11.07%,indicating that a plantation may have a relatively rapid litter decomposition process.In addition,forest conversion significantly altered the physical traits of Castanopsis carlesii leaf litter,such as leaf area,circumference and so on.Among them,the specific leaf area and leaf tissue density showed the highest coefficients of variation.In summary,it can be observed that litter standing storage decreased significantly after the conversion of

关 键 词：森林转换 凋落物现存量 分解程度 凋落叶性状 人工林 

分 类 号：S714[农业科学—林学]