摘要
凋落物分解在陆地生态系统碳循环和养分循环中起着重要作用,而气候条件是决定凋落物分解的主要因素。目前,对于高寒草原生态系统凋落物分解的研究不足,为探究气候变化背景下气象因子对紫花针茅(Stipa pur⁃purea)凋落物分解及养分释放过程的影响,本文以高寒草地紫花针茅内生真菌共生体植株为研究对象,采用凋落物分解袋法,分析带内生真菌(E+)与不带内生真菌(E-)紫花针茅凋落物分解特征以及凋落物组分的变化情况,并探讨气象因子对紫花针茅内生真菌共生体凋落物分解的影响。结果表明:E+紫花针茅凋落物分解速率高于E-,具有更短的分解周期;随着时间的延长,紫花针茅凋落物E+和E-凋落物全氮含量呈上升趋势,木质素含量由E+显著高于E-逐渐变为二者之间差异不显著,纤维素含量则逐渐变为E+显著低于E-(P<0.05)。无论E+和E-,紫花针茅凋落物重量以及质量损失速率与月平均气温和月平均地面温度呈显著相关关系(P<0.05),紫花针茅凋落物分解速率与降水量呈正相关,紫花针茅凋落物全氮含量与月平均气温、月平均地面温度和降水量呈显著正相关(P<0.05),木质素和纤维素含量与月平均气温、月平均地面温度和降水量呈负相关。日照时数对紫花针茅凋落物分解的影响较大,在分解过程中与日照时数相关性较强的是木质素、纤维素以及凋落物重量。总体来看,内生真菌能加速紫花针茅凋落物的分解进程,无论是E+还是E-,气象因子对紫花针茅凋落物分解的影响基本一致。
Litter decomposition has an important role in the carbon and nutrient cycling of terrestrial ecosystems.Climatic conditions are the main factors involved in litter decomposition.Currently,few studies have examined litter decomposition in alpine grassland ecosystems.To determine the effects of meteorological factors on the litter decomposition and nutrient release processes under a climate change background,the Stipa purpurea endophytic fungal symbiont was used along with the litter decomposition bag method to analyze the decomposition characteristics with endophytic fungi(E+)and without endophytic fungi(E-).The effect of meteorological factors on the decomposition rate of Stipa purpurea was analyzed.The results indicated that the decomposition rate of E+was higher compared with that of E-,whereas the decomposition cycle was shorter.With the extension of time,the total nitrogen content of Stipa purpurea showed an increasing trend,lignin content gradually changed from significantly higher in E+to no significant difference between the two,and the cellulose content gradually changed from significantly lower in E+compared with E-(P<0.05).Regardless of endophytic fungi,the litter weight and mass loss rate of Stipa purpurea were correlated with the mean monthly temperature and the mean ground temperature(P<0.05).Precipitation was positively correlated with the litter decomposition rate of Stipa purpurea,and the total nitrogen content of the litter was positively correlated with temperature and precipitation(P<0.05).The lignin and cellulose content were negatively correlated with temperature and precipitation.The duration of sunshine had a positive effect on the decomposition of litter,and the lignin,cellulose,and litter weight content were strongly correlated with sunshine duration.Overall,endophytic fungi accelerate the decomposition of Stipa purpurea litter.For E+and E-,the effect of meteorological factors on the decomposition of Stipa purpurea litter was consistent.
作者
郭强
王玉琴
宋梅玲
GUO Qiang;WANG Yuqin;SONG Meiling(Xinghai County Meteorological Bureau,Xinghai 813300,Qinghai,China;Academy of Animal and Veterinary Science of Qinghai University,Xining 810016,Qinghai,China)
出处
《干旱区研究》
北大核心
2025年第7期1269-1278,共10页
Arid Zone Research
基金
青海省“高端创新创业人才计划”拔尖人才培养计划项目。
关键词
紫花针茅
内生真菌
凋落物分解
气象因子
高寒草地
Stipa purpurea
endophytic fungi
litter decomposition
meteorological factors
alpine grassland
作者简介
郭强(1987-),男,工程师,主要从事综合气象服务方面的研究.E-mail:gq0971@hotmail.com;通讯作者:宋梅玲.E-mail:meilings@163.com。
