毛乌素沙地不同林龄杨柴灌木林土壤呼吸及其影响因素  

Research on soil respiration and its influence factors on Hedysarum laeve shrubbery of different ages at Mu Us sandy land

作　　者：海龙 周梅[1] 张嘉開 洪光宇 李凤滋[2,3] 费菲 HAI Long;ZHOU Mei;ZHANG Jiakai;HONG Guangyu;LI Fengzi;FEI Fei(College of Grassland,Resources and Environment,Inner Mongolia Agricultural University,Hohhot 010018,Inner Mongolia,China;Inner Mongolia Academy of Forestry Sciences,Hohhot 010010,Inner Mongolia,China;Key Laboratory For Sandy Land and Desert Ecosystem and Ecological Engineering of Inner Mongolia Autonomous Region,Hohhot 010010,Inner Mongolia,China)

机构地区：[1]内蒙古农业大学草原与资源环境学院,内蒙古呼和浩特010018 [2]内蒙古自治区林业科学研究院,内蒙古呼和浩特010010 [3]内蒙古自治区沙地(沙漠)生态系统与生态工程重点实验室,内蒙古呼和浩特010010

出　　处：《干旱区研究》2023年第7期1107-1116,共10页Arid Zone Research

基　　金：国家自然科学基金项目(41867043);内蒙古自治区草原英才青年创新人才项目(内人社办发[2020]214号);鄂尔多斯市科技重大专项[2022EEDSKJZDZX010-3-(3)]。

摘　　要：为探究沙漠化逆转过程中林地土壤呼吸速率和通量变化趋势及其主要影响因子,本文选择毛乌素沙地林龄为9 a、18 a和30 a杨柴人工灌木林和未造林流动沙地(CK),用Li-8100A土壤碳通量监测系统对土壤呼吸速率进行定位观测,并对主要环境影响因子进行了测定。结果表明:(1)土壤呼吸速率和通量均在植物生长季5—10月呈现出先升高后降低的单峰曲线变化规律,最高值出现在7月。(2)土壤呼吸速率和通量随杨柴林龄增长呈持续增加趋势,而呼吸速率温度敏感性(Q10)则呈持续下降趋势。生长季5—10月杨柴林各样地土壤呼吸平均速率大小为:30 a(2.16μmol·m^(-2)·s^(-1))>18 a(1.98μmol·m^(-2)·s^(-1))>9 a(1.41μmol·m^(-2)·s^(-1))>CK(0.24μmol·m^(-2)·s^(-1));土壤呼吸碳通量值大小顺序为:30 a(365.74 g C·m^(-2))>18 a(313.63 g C·m^(-2))>9 a(218.66 g C·m^(-2))>CK(40.08 g C·m^(-2))。(3)CK、9 a和18 a样地土壤呼吸速率季节性变化主要受土壤温度和水分的耦合作用(P<0.01),而30 a样地的主控因子为土壤温度(P<0.01)。(4)土壤呼吸碳通量与植被生物量、土壤有机碳和全氮含量均呈显著正相关关系(P<0.05)。To explore the trend of the change of the soil respiration flux and main influencing factors in the process of desertification reversal,9 a,18 a and 30 a ages of Hedysarum laeve shrubbery and no afforestation quicksand land(CK)were selected at Mu Us sandy land in Northern China.Using the Li-8100 carbon flux observation system which produced in the United States,measured soil respiration from May to October.At the same time,the main influencing factors were determined and analyzed.The results showed that:(1)Both soil respiration rate and flux increased first and then decreased in the growth season from May to October,and the highest value appeared in July.(2)The soil respiration rate and flux showed a continuous increasing trend with the age of the Hedysarum laeve shrubbery,the Q10 value shows a continuous downward trend.From May to October in the growing season,the order of average soil respiration rate was:30 a(2.16μmol·m^(-2)·s^(-1))>18 a(1.98μmol·m^(-2)·s^(-1))>9 a(1.41μmol·m^(-2)·s^(-1))>CK(0.24μmol·m^(-2)·s^(-1));the soil respiration carbon flux was 30 a(365.74 g C·m^(-2))>18 a(313.63 g C·m^(-2))>9 a(218.66 g C·m^(-2))>CK(40.08 g C·m^(-2)).(3)The seasonal variation of soil respiration rate in CK,9 a and 18 a plots was mainly affected by the coupling effect of soil temperature and water(P<0.01),while the main control factor in 30 a plots was soil temperature(P<0.01).(4)Soil respiration flux was positively correlated with vegetation biomass,soil organic carbon and total nitrogen content(P<0.05).

关 键 词：土壤呼吸 影响因素 杨柴 毛乌素沙地 

分 类 号：S714[农业科学—林学]