陕北毛乌素沙漠黑沙蒿根系分布特征研究  

Study on Root Distribution of Artemisa Ordosica in Mu Us Sandy Land

作　　者：康博文[1] 刘建军[1] 孙建华[1] 李岩峰[2] 

机构地区：[1]西北农林科技大学林学院,陕西杨陵712100 [2]内蒙古巴彦淖尔市水土保持站,内蒙古巴彦淖尔015000

出　　处：《水土保持研究》2010年第4期119-123,共5页Research of Soil and Water Conservation

基　　金：国家林业局948项目(2006-04-16)

摘　　要：研究沙生植物根系空间分布特征对制定沙质困难立地植被恢复与重建技术路线,选定适宜树种,提高造林成活率、保存率和效益,都会起到非常重要的作用。采用埋置网状沙袋土芯、分层挖掘、根系分析系统等方法对毛乌素沙地主要优势植物黑沙蒿的根系生长和分布特征进行了测定,结果表明:(1)不同年龄的黑沙蒿根系生物量变化范围及其在各土层中的分布规律各不相同。黑沙蒿根系生物量随着树龄的增加而增加,在一定时期达到最大值,然后逐渐下降并趋于稳定;其根系分布也随年龄的增加向深层土壤延伸,在垂直方向上,根生物量随深度增加呈指数递减。1～5年生黑沙蒿根系生物量主要分布在0-60cm土层,占总根系生物量百分比分别为99.06%、97.71%、94.31%、93.82%、84.35%。0-20cm土层根系生物量占根总生物量百分比随着树龄的增加逐渐减小,20-60cm土层的根系生物量百分比则随着树龄的增大先增大后减少。(2)黑沙蒿根长的变化特征与其根生物量的分布规律较为相似,随着年龄的增加不同土层间根长的变幅增大,但随着土壤深度的增加沙蒿根长呈指数函数模式递减。(3)1～5年生黑沙蒿比根长在0-200cm土层平均比根长随着树龄的增加而减小,1年生黑沙蒿的比根长最大,5年生黑沙蒿用以构建根系的碳投入最多,比根长最小。黑沙蒿用以构建根长的生物量投入效率也随着年龄的增加而减小。同龄黑沙蒿在不同土层的比根长也各不相同,不仅说明了植物对其生存环境具有较高的可塑性,也反映了土壤环境条件存在差异。Study on root distribution plays an important role in the vegetation recovery and regeneration,the choice of suitable species,improving afforestation survival,preserving rate,and benefit to master sandy plant root growth and its vertical distribution.This paper studied the spatial-temporal root distribution of the Arternisia ordosica in moving dune,semi-fixed dune,and fixed dune of Mu Us sandy land by embedding reticular bag soil core,layered excavating,and analysis system of root.The range of Arternisia root biomass was varied by the ages and the distributions in the soil layers were different.The root biomass was increased with the ages,and come to the maximum in a certain period of growth,then gradually decreased and kept stable.The roots extended to the deeper soil layers along with the increase of age,and the root biomass exponentially declined with the depth of soil.The root biomasses of Arternisia at the age of one to five years were mainly in 0-60cm soil layer,whose percentage were 99.06%,97.71%,94.31%,93.82%,84.35%.In 0-20cm,the percentage of the root biomass of total root（PBT）reduced with the ages.In 20-60cm,the PBT increased at first and then decreased.The variation and the distribution of the root length were similar as the pattern of the biomass,and the root length difference in different soil layers increased with the ages,but the root length exponentially declined with the depth of soil.Specific root length（SRL）can reflect the characteristics of habitat flexibility of plants.The variation of SRL of Arternisia showed that the means of SRL decreased with the ages in 0-200cm soil layer and the one year was the largest in five age stages.The five-year plant input the most carbon but has the least SRL.The efficiency of inputting carbon for root length construction decreased with the increase of age.The SRL was different in different soil layers at the same age.It was indicated that the plants had a high plasticity to their living environment and reflected the difference among the soil conditions

关 键 词：毛乌素沙漠 黑沙蒿 根系 分布特征 

分 类 号：Q945.3[生物学—植物学]