i am conducting a belowground biomass estimation using minirhizotrons (in which a camera will be fixed to take the images of the roots) and a software for estimating the biomass. However, I am unsure to calculate the root turnover (biomass of dead roots). The sampling interval will be 2-3 weeks and within this interval, it is possible that some fine roots (<2mm in diameter) will die and the biomass will be underestimated. Can anyone suggest me to overcome this problem?