摘要
在河西走廊中部,采用挖掘法挖取红砂和白刺根系,应用拓扑学与分形理论分析了根系构型的特征.结果表明:2种荒漠植物根系的拓扑指数均较小,根系分支模式均近似为叉状分支结构.红砂和白刺根系具有较好的分形特征,其分形维数分别为(1.18±0.04)和(1.36±0.06);分形维数、分形丰度与根系平均连接长度均呈显著正相关.2种荒漠植物根系的平均连接长度均较大,以扩大植物的有效营养空间,从而适应干旱贫瘠的土壤环境.2种荒漠植物根系分支前的横截面积等于根系分支后的横截面积之和,验证了Leonardo da Vinci法则.对17个根系构型参数进行主成分分析,根系拓扑指数、根系连接数量、逐步分支率和根系直径4个根系构型参数能很好地表示2种荒漠植物根系构型特征.
In this study, the root systems of desert plant species Reaumuria soongorica and Nitraria tangutorum in the central Hexi Corridor of Northwest China were excavated by shovel, and the characteristics of the plant root architecture were analyzed by using topology and fractal theory. The root topological indices of the two desert plants were small, and the root branching patterns were herring- bone-like. The roots of the two desert plants had obvious fractal characteristics, with the fractal dimension of R. soongorica and N. tangutorum being （1.18±0.04） and （ 1.36±0.06）, respectively. The root fractal dimension and fractal abundance were significantly positively correlated with the root average link length. The root average link lengths of the two plants were long, which enlarged the plants＇ effective nutrition space, and thus, made the plants adapt to the dry and infertile soil environment. The sums of the root cross-sectional areas before and after the root bifurcation of the two desert plants were equal, which verified the principle of Leonardo da Vinci. A total of 17 parameters of root architecture were analyzed by the principal component analysis. The parameters of root topological structure, numbers of root links, stepwise branching ratio, and root diameter could well present the root architecture characteristics of the two desert plants.
出处
《应用生态学报》
CAS
CSCD
北大核心
2013年第1期25-31,共7页
Chinese Journal of Applied Ecology
基金
国家国际科技合作专项(2012DFR30830)
甘肃省科技支撑计划项目(1204NKCA084)
甘肃农业大学校创新基金项目(GAV-CX1112资助
关键词
荒漠植物
根系构型
拓扑指数
分形维数
分支率
连接长度
desert plant
root architecture
topological index
fractal dimension
branching ratio
link length.
