应用实测含水率剖面估算冬小麦相对根长密度分布

Estimating normalized root length density distribution of winter wheat using measured soil water content profiles

根长密度是根系研究中不可缺少的一个参数,但其适时准确的测定却存在相当的困难。该文应用平均根系吸水速率反求方法,提出了在已知两个实测含水率剖面的条件下,估算相对根长密度分布的方法,并通过田间实验和土柱实验对该方法进行了检验,结果表明:该方法可以较好地估算相对根长密度的分布,为土壤水分运移的连续模拟提供较为可靠的参数。

It is very difficult, even not impossible, to measure root density timely and accurately, especially in the field. However, it is an essential parameter for root study. In this study, an approach to estimating the normalized root length density distribution was proposed, which was based on two measured soil water content profiles and the inverse method to estimate the average root-water-uptake rate. The approach was also used to estimate the normalized root length density distributions of winter wheat grown in soil columns and in the field. The results showed that the approach was reliable to estimate the normalized distributions of relative root length density, compared with the measured values. Therefore, the estimated effective root density parameter can be provided for root-water-uptake models and soil water flow can be simulated continuously even without any measured root density information.