草业学报2025，Vol.34Issue(11)：31-39,9.DOI:10.11686/cyxb2024489
降水变化下荒漠草原优势植物功能性状对生物量分配的调节机制
Regulatory mechanisms of biomass allocation governed by functional traits of dominant plants in desert steppe under precipitation changes
摘要
Abstract
Plant functional traits are key characteristics determining plant growth and survival.The pattern of biomass allocation in plants is crucial for their ecological adaptability to varying environmental conditions.This study investigated the effects of precipitation changes on the functional traits and biomass allocation of Stipa caucasica and Allium polyrhizum,two dominant plant species in the Urat Desert steppe,through controlled simulation experiments.Root functional traits(specific root length,root tissue density,and specific root area),leaf functional traits(specific leaf area,leaf dry matter content,and leaf tissue density),aboveground biomass,belowground biomass,and root∶shoot ratio were systematically measured under three precipitation treatments(50%decrease in precipitation,natural precipitation,and 50%increase in precipitation).The results showed that:1)The specific leaf area of A.polyrhizum increased significantly under reduced precipitation,whereas the root and leaf functional traits of S.caucasica showed no significant response to precipitation changes.2)Under a 50%reduction in precipitation,the aboveground biomass of A.polyrhizum decreased significantly,while its belowground biomass showed no significant change.However,the root∶shoot ratio was significantly higher than that under natural precipitation.In contrast,under a 50%increase in precipitation,both the aboveground and belowground biomass of A.polyrhizum remained unchanged.For S.caucasica,no significant changes in aboveground biomass,belowground biomass,or root∶shoot ratio were observed under the three tested precipitation regimess.3)Precipitation changes indirectly affected the biomass allocation of S.caucasica by modifying soil electrical conductivity,while they influenced the biomass allocation of A.polyrhizum through the modulation of specific leaf area.The findings provide theoretical insights into the mechanisms of biomass allocation regulation in typical desert steppe plants under reduced,normal or increased precipitation conditions.关键词
荒漠草原/降水变化/生物量分配/功能性状/沙生针茅/碱韭Key words
desert steppe/precipitation change/biomass allocation/functional traits/Stipa caucasica/Allium polyrhizum引用本文复制引用
马蓉,李俊瑶,岳平,马旭君,白珍,庄玲,白敬,赵学勇,王少昆..降水变化下荒漠草原优势植物功能性状对生物量分配的调节机制[J].草业学报,2025,34(11):31-39,9.基金项目
内蒙古自治区科技重大专项"揭榜挂帅"项目(2024JBGS00130203)资助. （2024JBGS00130203）
