摘要
枯落物是草地生态系统的重要组分,影响着植物对水分和养分的吸收和循环。通过对内蒙古短花针茅荒漠草原围封10年的样地进行不同程度的枯落物去除(中度、重度去除和对照)试验,揭示了2014~2017年枯落物去除对荒漠草原功能群和生物量的影响。结果表明:枯落物去除降低了土壤水分含量,重度去除较中度去除的土壤水分下降幅度更大。枯落物重度去除后荒漠草原地上生物量平均增加43%(2015~2017年)。枯落物去除后各功能群在降水充沛的年份表现出显著差异,多年生杂类草、灌木和小半灌木的生物量随着枯落物去除量的增加而增加,而禾草总量则是在中度枯落物去除后达到最大生物量;RDA分析表明,枯落物质量与土壤水分呈正相关关系,枯落物在土壤水分较高时对地上生物量以及各功能群生物量的影响增强;多年生丛生型禾草与一、二年生草本、灌木和小半灌木存在资源竞争。枯落物在水分充足的情况下,调节着荒漠草原植物功能群结构和地上生物量。由此可见,适量的枯落物留存有利于内蒙古荒漠草原生产力的可持续发展。
Litter is a pivotal constituent of grassland ecosystems,with profound impacts on plant water and nutrient acquisition,as well as recycling.This study,conducted between 2014 to 2017,aimed to assess the effects of litter removal on the functional groups and biomass of Stipa breviflora desert steppe in Inner Mongolia.Experimental plots,enclosed for 10 years,were employed to execute experiments involving various degrees of litter removal,including moderate,heavy and control treatments.The results showed that the litter removal led to a reduction in soil moisture,with a more pronounced decrease observed in the heavy removal treatment compared to the moderate treatment.Intriguingly,heavy litter removal substantially increased the average aboveground biomass by 43%from 2015 to 2017.Across the years characterized by abundant precipitation,plant functional groups demonstrated significant variations.The biomass of perennial forbs,shrubs,and small subshrubs exhibited increments as litter removal intensified,while the total biomass of Gramineae grass peaked following moderate litter removal.The redundancy analysis(RDA)revealed a positive correlation between litter mass and soil moisture.Moreover,the influence of litter on both aboveground biomass and the biomass of individual functional groups was more pronounced under conditions of higher soil moisture.Notably,perennial bunch grasses were observed to compete for resources with annual and biennial herbs,shrubs,and small subshrubs.In essence,litter played a pivotal role in regulating the structure of plant functional groups and aboveground biomass within desert steppe,particular under conditions of sufficient water.Therefore,the retention of an appropriate quantity of litter is deemed advantageous for the sustainable enhancement of productivity in the desert steppe of Inner Mongolia.
作者
王静
杨建庆
高新磊
吕世杰
屈志强
WANG Jing;YANG Jianqing;GAO Xinlei;LYU Shijie;QU Zhiqiang(College of Grassland,Resources and Environment,Inner Mongolia Agricultural University/KeyLaboratory of Grassland Resources/Key Laboratory of Forage Cultivation Processing and High EfficientUtilization/Inner Mongolia Key Laboratory of Grassland Management and Utilization,Hohhot 010011,China;College of Agriculture,Chifeng University/Key Laboratory of Agro-Ecological Protection&Exploitation and Utilization of Animal and Plant Resources in Eastern Inner Mongolia,Chifeng 024000,China;College of Science,Inner Mongolia Agricultural University,Hohhot 010018,China)
出处
《中国草地学报》
CSCD
北大核心
2023年第11期24-32,共9页
Chinese Journal of Grassland
基金
内蒙古自治区自然科学基金项目(2022MS03067,2020BS03013)
内蒙古农业大学草学学科青年基金项目(IMAUCXQJ2023001)。
关键词
枯落物
去除
荒漠草原
功能群
生物量
Litter
Removal
Desert steppe
Functional groups
Biomass
