Ma, C., Li, Y., You, H., Long, H., Yu, W., Gao, Y. and Wang, Y. 2021. Nonstructural carbohydrates, carbon and nitrogen concentrations in fine roots of Quercus variabilis secondary forests after two different periods of regeneration. Forest Systems. 30, 1 (Apr. 2021), e001. DOI:https://doi.org/10.5424/fs/2021301-16550.