Fine root is indispensable for the growth of trees and its dynamics is sensitive to environmental change. Therefore, understanding fine root phenology is important for evaluating the impact of climate change on forests. However, little is known about the spatial and temporal variation of root phenology in order to obtain representative phenology pattern in a forest. In this study, we aimed to understand the variation of fine root dynamics between the investigating points, using scanner method that can obtain a wide observation window nondestructively.
We collected root images of 0-20 cm soil depth once a month for one year at four locations in a temperate mixed forest in Hyogo Prefecture. We analyzed annual growth and death pattern from the acquired image. Furthermore, in order to determine the spatial variation of fine root phenology, we quartered the images and compared the growth and death patterns among them.
In general, fine root growth and death occurred from spring to autumn. However, fine root biomass differed between the four observations site, and the phenology patterns differed between them. Our results suggest that it is necessary to consider about spatial variation of fine root dynamics, if fine root phenology is evaluated in stand scale.