摘要
毛竹(Phyllostachys edulis)林是长江三角洲地区典型的森林类型,在缓解温室效应、维持碳平衡等方面具有重要作用。林地凋落物层可能是影响二氧化碳(CO_(2))和氧化亚氮(N_(2)O)在土壤与大气之间交换的重要因素。以浙江省安吉县毛竹林为对象,采用静态箱-气相色谱法,分析清除凋落物(S)和保留凋落物(SL)处理对土壤CO_(2)和N_(2)O通量的影响及调控因素。结果表明,观测期内毛竹林土壤为CO_(2)的源,夏季排放最强;S处理的毛竹林土壤由夏秋季的N_(2)O排放源转变为冬春季的N_(2)O吸收汇;而SL处理的土壤则始终表现为N_(2)O的排放源。凋落物显著影响毛竹林地土壤CO_(2)和N_(2)O通量。S处理下的CO_(2)年均排放通量(779.27 mg·m^(-2)·h^(-1))高于SL处理(520.07 mg·m^(-2)·h^(-1)),凋落物对土壤CO_(2)通量的平均抑制贡献率为33.26%;相反,S处理下的N_(2)O年均排放通量(2.95μg·m^(-2)·h^(-1))则低于SL处理(16.42μg·m^(-2)·h^(-1))。土壤温度是决定竹林土壤CO_(2)通量的重要因素,其次为土壤有机碳;清除凋落物处理下的土壤温度是影响N_(2)O通量变化的主要因素,而保留凋落物处理下全氮则是改变N_(2)O通量的关键因子。总体而言,毛竹林地以竹叶为主的凋落物层会抑制土壤CO_(2)的排放,促进N_(2)O的排放。该研究为深入理解竹林土壤地气交换的调控机制提供了重要依据,建议在评估林地温室气体收支时考虑凋落物层的影响。
Moso bamboo(Phyllostachys edulis)forest is a typical forest type in the Yangtze River Delta region and plays a crucial role in mitigating the greenhouse effect and maintaining the carbon balance.The forest litter layer may significantly influence the exchange of carbon dioxide(CO_(2))and nitrous oxide(N_(2)O)between the soil and atmosphere.This study was conducted in a Moso bamboo forest in Anji County,Zhejiang Province,China,where two treatments were implemented:soil without litter(S),and soil with litter(SL).The static chamber gas chromatography method was used to analyze the effects of these treatments on soil CO_(2)and N_(2)O fluxes and the regulating factors involved.The results indicated that the Moso bamboo forest soil was a net source of CO_(2)during the observation period,with the highest emissions occurring in summer.Soil without litter turned from a net N_(2)O source to slight N_(2)O sinks from summer and fall to winter and spring,whereas soil with litter was consistently a net N_(2)O source.The litter significantly affected soil CO_(2)and N_(2)O fluxes that the average annual CO_(2)flux under the S treatment(779.27 mg·m^(-2)·h^(-1))significantly higher than that the SL treatment(520.07 mg·m^(-2)·h^(-1)),indicating a 33.26%inhibitory contribution of litter to soil CO_(2)flux.Conversely,the average annual N_(2)O flux under the S treatment(2.95μg·m^(-2)·h^(-1))was lower than that under the SL treatment(16.42μg·m^(-2)·h^(-1)).Soil temperature is a key factor in the CO_(2)flux in bamboo forest soils,followed by soil organic carbon.Soil temperature was the primary factor influencing the variation in N_(2)O flux in the S plots,whereas total nitrogen content was the main factor influencingN_(2)O flux changes in the SL plots.Overall,the litter layer,which is mainly composed of bamboo leaves,inhibits soil CO_(2)emissions,but increases N_(2)O emissions.This study provides important insights into the regulatory mechanisms of soil-atmosphere exchanges in bamboo forests and suggests that the impact of litter must be considered when evaluating the greenhouse gas budget of forests.
作者
徐飞
贾沁琦
郭娜
胡嘉豪
方双喜
XU Fei;JIA Qinqi;GUO Na;HU Jiahao;FANG Shuangxi(Department of Environment,Zhejiang University of Technology,Hangzhou 310014,P.R.China;Zhejiang Carbon Neutral Innovation Institute,Zhejiang University of Technology,Hangzhou 310014,P.R.China)
出处
《生态环境学报》
北大核心
2025年第3期380-390,共11页
Ecology and Environmental Sciences
基金
国家重点研发计划项目(2023YFC2305205)
国家自然科学基金项目(42275113)。
