腾格里沙漠南缘唐古特白刺克隆分株生长格局及枝系构型分析  

Analysis of clonal growth patterns and branching architecture of Nitraria tangutorum clonal ramet in the Southern margin area of the Tengger Desert

作　　者：周资行[1] 李真[2] 焦健[1] 李毅[1] 令凡 

机构地区：[1]甘肃农业大学林学院,甘肃兰州730070 [2]中国药科大学生命科学与技术学院,江苏南京210009

出　　处：《草业学报》2014年第1期12-21,共10页Acta Prataculturae Sinica

基　　金：国家国际科技合作专项(2012DFR30830);国家科技部(农转资金)项目(2009GB2G100375);农业科技成果转化资金计划甘肃省科技厅项目(0805XCNA063)资助

摘　　要：选取腾格里沙漠南缘景泰点(JBDZ)、古浪点(GMLT)和民勤点(MQQF)及对照点兰州(LZNS)天然分布的唐古特白刺克隆种群,结合统计检验和分形理论分析研究唐古特白刺克隆分株生长格局及枝系构型的环境异质性。结果表明,唐古特白刺表现出较为明显的形态可塑性,克隆分株存在显著差异,随着水分梯度递减,分株间距逐渐增大,对照点LZNS分株各指标普遍高于沙漠南缘三地,分株克隆生长格局呈现密集型,MQQF分株克隆生长格局有一定的游击趋势。克隆整合使得唐古特白刺克隆种群枝系构型表现复杂,LZNS的各级分枝角最小,MQQF最大;枝径比波动大,LZNS各级枝径比普遍最大,MQQF最小;LZNS唐古特白刺克隆植株总体分枝率和逐步分枝率均显著高于MQQF,但与JBDZ和GMLT差异不大;枝系分枝强度和各分维数表现较为一致,均以LZNS较大,沙漠南缘三地则表现出随水分梯度递减,白刺克隆植株分维数逐渐下降,枝系的空间格局趋于简单。研究表明在水分条件差的生境,唐古特白刺克隆种群获取资源的主要对策是,分株间距增加,分枝角度加大,而分枝强度变小,克隆生长格局趋于游击型,利于基株跨越和逃离逆境以获取水分。Based on the declining rainfall gradient in Gansu province,China,Jingtai Baidunzi （JBDZ）,Gulang Malutan （GMLT）,Minqin Qinfeng （MQQF） and Lanzhou Nanshan （LZNS） were used to compare ramet population characteristics and clonal branching architecture of Nitraria tangutorum.N.tangutorum had obvious morphological plasticity and considerable differences existed in ramet population characteristics in different regions.The ramet spacing gradually increased with a decline in moisture.Most indexes of ramet population in Lanzhou were higher than those in the three desert plots.Clonal growth patterns presented a phalanx in Lanzhou,but were irregular in Minqin.Clone integration made the clone branching architecture of N.tangutorum complex.All branch angles were smallest in LZNS,and biggest in MQQF.The ratios of branch diameter fluctuated; most of the branch diameter ratios were largest in Lanzhou,but the expression was the opposite in Minqin.The general bifurcation ratios and the gradual bifurcation ratios in Lanzhou were higher than in Minqin,but there were no substantial differences between Lanzhou and Jingtai,Gulang.Branching intensity and fractal dimensions were similar,and all were highest in Lanzhou.The fractal dimensions declined and branching space structure tended to be simple as the moisture declined in the three desert plots.In habitats with poor water conditions,the main strategies to increase resources of N.tangutorumt were：increased ramet spacing and branch angle,weakened branching intensity,and the irregular type clonal growth pattern which are conducive to ramets to escape adversity in order to obtain moisture.

关 键 词：唐古特白刺克隆种群 分株 生长格局 枝系构型 形态可塑性 分维数 腾格里沙漠南缘 

分 类 号：Q948[生物学—植物学]