中国农业大学学报2024，Vol.29Issue(4)：264-273,10.DOI:10.11841/j.issn.1007-4333.2024.04.23
海拔和坡向对色季拉山高山杜鹃凋落物分解的影响
Effects of elevation and slope orientation on litter decomposition of Rhododendron simsii in Mount Segrila
摘要
Abstract
Litter is an important source of organic matter in forest ecosystems,and its decomposition process is driven by many abiotic factors.In order to investigate the decomposition dynamics of litter at different elevations and slope directions in alpine forest,a two-year litter burial experiment was conducted with Rhododendron simsii litter at 4 gradient elevations(3 500,3 700,3 900 and 4 100 m)and 2 slope directions of northwestern and southeastern slopes in in Mount Segrila.The Olson model was used to clarify the degradation pattern of litter,and the factors affecting the litter decomposition were investigated in the mass loss of lignocellulose and the physicochemical properties of the soil.The results showed that:The mass residual rate of litter at different elevations and slope directions decreased with the increase ofdecomposition time,ranging from 36.65％ to 75.99％.The decomposition speed of litter and lignocellulose were generally greater on negative slopes than that on positive slopes.The degree of lignin decomposition was the highest,contributing more than 50％ to the litter mass loss;decomposition rate was the fastest and the half-life and turnover period was the shortest on the positive slope at 3 700 m.The nutrient content of carbon,nitrogen,phosphorus,and potassium in soil was mainly affected by slope direction and litter decomposition time,with relatively small differences among different elevations.Elevation,slope direction,decomposition time,and their interactions all had a significant effect on litter decomposition(P＜0.01),and the soil moisture and the carbon to nitrogen ratio were also important factors affecting litter decomposition.This study provides a theoretical basis for the decomposition pattern and influencing factors of litter in alpine forests.关键词
海拔/坡向/凋落物/分解/高寒森林Key words
elevation/aspect of slope/litter/decomposition/apline forest分类
生物科学引用本文复制引用
侯卓男,李欣彤,张新军,马恬恬,李傲,赵金月,王瑞红,魏雨泉..海拔和坡向对色季拉山高山杜鹃凋落物分解的影响[J].中国农业大学学报,2024,29(4):264-273,10.基金项目
国家自然科学基金项目(31960013) （31960013）
西藏高原森林生态教育部重点实验室开放课题(XZA-JYBSYS-2020-02) （XZA-JYBSYS-2020-02）
西藏自治区科技创新基地自主研究项目(XZ2022JR0007G) （XZ2022JR0007G）
