DEVELOPMENT OF THE SYSTEM FOR DIAGNOSING CROP ROOT GROWTH USING FRACTAL ANALYSIS.

本研究的目的如下：1. 通过分形分析量化和评价作物根系的形态。2. 建立一种适用于根系生长和功能诊断的简单方法。3. 从有限的样本数据中模拟和估计整个根系在土壤中的分布。该研究的最终目标是开发计算机辅助系统，以评估和模拟土壤中生长的根系的生长和功能，同时减少采集样本的劳动和时间。1. 影响豆科植物幼苗根系分形维数的主要参数是根长、根尖数量和拓扑结构。利用根长和根尖数的测量数据，可以用分形维数来量化系统的拓扑结构。2. 各主要参数对根系分形维数的影响程度随根系生长速率的变化而变化。3. 不同土壤深度根系样品的分形维数差异较大，分形维数在不同水稻品种间的分布曲线也有显著差异。根长和根重密度与分形维数密切相关。这些结果表明，分形维数是评价和诊断田间土壤根系构型和生长状况以及估计和模拟土壤根系分布的一个简单而有用的指标。

The objectives of this research are as follows ; 1. Quantify and evaluate the morphology of crop roots through fractal analysis. 2. Develop a simple method applicable to the diagnosis of root growth and functions. 3. Simulate and estimate the distribution of whole root system in soil from the limited sample data. The final goal of the research is to develop the computer aided system for evaluating and simulating growth and function of root systems grown in soil with minimum labor and time spend for sample acquisition. 1. The major parameters affecting to fractal dimension of root systems of legume seedlings were root length, number of root tip and topology. Topology of the system can be quantified by fractal dimension with the measured data of root length and root tip number. 2. The influence magnitude of each major parameter to fractal dimension of root systems was altered by growth rate of the root. 3. The fractal dimension of root samples taken from different soil depth was varied considerably, and the distributiion profile of fractal dimension was characteristically different among rice varieties. The length and weight density of roots collected from soil cores were closely correlated with fractal dimension. These results suggest that fractal dimension is a simple and useful index for evaluating and diagnosing the root architecture and growth as well as for estimating and simulating root distribution in the field soil.