荒漠草地4种灌木生物量分配特征  

Biomass Allocation Patterns of Four Shrubs in Desert Grassland

作　　者：杨昊天[1] 李新荣[1] 刘立超[1] 贾荣亮[1] 王增如[1] 李小军[1] 李刚[1] 

机构地区：[1]中国科学院寒区旱区环境与工程研究所沙坡头沙漠试验研究站,甘肃兰州730000

出　　处：《中国沙漠》2013年第5期1340-1348,共9页Journal of Desert Research

基　　金：中国科学院战略性先导科技专项(XDA05050406-1);国家自然科学基金项目(40930636;41240003;41271061);中国科学院"西部之光"人才培养计划西部博士项目资助

摘　　要：生物量是植物积累能量的主要体现,其在各器官中的分配是植物对环境适应的结果,反映了植物的生长策略。生物量分配会影响不同碳库之间的碳周转,进而影响陆地生态系统碳循环。选取腾格里沙漠东南缘荒漠草地的4种优势灌木种,采用全挖法在个体水平上研究了各器官的生物量以及地下-地上生物量关系（根冠比R/S）,试图揭示生物量在各器官中以及地下-地上的分配格局。结果表明：不同物种生物量在地上部分各器官中的分配策略不同;R/S也不相同,其中红砂（Reaumuria soongarica）最大（中值为0.972）,珍珠（Salsola passerina）（中值为0.744）和驼绒藜（Ceratoides latens）（中值为0.670）次之,盐爪爪（Kalidium foliatum）最小（中值为0.179）,这表明4种灌木具有各自独特的生长策略。随着灌木的生长,冠幅和生物量不断增大,R/S呈下降趋势,说明植物在开始生长阶段对限制性的水分和养分可能有更高的竞争需求。4种灌木的根系分布在不同种间也存在差异,盐爪爪根系较浅（主要分布在0~30cm土层）,其次是珍珠（主要分布在0~50cm土层）,驼绒藜和红砂的根系分布较深（主要分布在0~70cm土层）。驼绒藜、红砂和珍珠的地下-地上生物量分配模式支持等速生长假说,而盐爪爪的地下-地上生物量分配模式则不支持该假说。4种灌木的地上生物量与地下生物量（经对数转换）均呈极显著的线性相关关系（p〈0.001）,决定系数介于0.81~0.93之间,这一相关关系可以应用于对荒漠草地地下生物量的估算。本结果有助于进一步研究荒漠生态系统的生物量分配格局和碳循环。Biomass mainly reflected the accumulated energy by plant. Plant species have evolved specialized strategies to regulate biomass allocation among various organs or between above- and belowground biomass （R/S）. Biomass allocation can affect carbon turnover among different pools and the terrestrial ecosystem carbon cycling. We investigated biomass allocation patterns and characters of root distribution of four com- mon shrubs on individual levels in desert area, southeast of the Tengger Desert, China. Our results indica- ted that the biomass allocation strategy in above ground organs were different among four shrubs, the R/S were also different. These results reflect every shrub have evolved their unique growth strategy. The cano- py and biomass increased and R/S decreased with the growth of shrubs. Shrubs may have higher competition needs for limited resources at the young than older stage. Root biomass distribution are different among Ka- lidium foliatum （in the uppermost 0-30 cm of the soil）, Salsola passerina （in the uppermost 0-50 cm of the soil）, Ceratoides tatens and Reaumuria soongorica （in the uppermost 0-70 cm of the soil）. Re- duced major axis analysis showed that the slopes of the relationship between above- and belowground biomass of Ceratoides lateens, Salsola passerine and Reaumuria soongorica close to 1, which support isometric scaling＇ hypothesis. However, the slope of the relationship between above- and belowground biomass of Ka- lidium foliatum was significantly different from 1.0, which don＇t support this hypothesis. There is a sig- nificant linear relationship between relationship can be used to estimate above- and belowground biomass after belowground biomass effectively. logarithmic transformation. The

关 键 词：地下-地上生物量比 生物量分配 荒漠草地 等速生长 腾格里沙漠 

分 类 号：Q948.122[生物学—植物学]