Decomposition of roots and leaves of Quercus acutissima and Pinus densiflora according to litterfall layer

Hyung Won Kim1*, Ye Jin Kong1, Sang Hyun Park1, Woo Bin Youn1, Jong Chan Yeo1,

Hyun Ju Lee1, Carayugan Anog Mark Bryan1, Byung Bae Park1

(1Department of Environment and Forest Resources, Chungnam National University)

Abstract: This study was conducted to investigate how artificial manipulation of the litterfall layer affects the decomposition of roots and leaves. It was carried out in a deciduous broadleaf forest in Daejeon, South Korea, using samples of roots and leaves from two representative tree species: Quercus acutissima (broadleaf) and Pinus densiflora (coniferous). Roots and leaves play a crucial role in nutrient cycling within forest ecosystems, contributing to carbon and nutrient storage in the soil and maintaining biodiversity. Climate change influences tree physiology, altering litterfall patterns and consequently modifying the forest's litterfall layer. In this study, three different litterfall layer treatments were applied: no layer (×0), control (×1), and double layer (×2). The decomposition rates of roots and leaves were measured using a litterbag method. For the roots, two diameter classes (0-2mm and 2-5mm) were distinguished. The decomposition rate of the roots was higher for the 0-2mm diameter roots compared to the 2-5mm diameter roots in both Q. acutissima (QA) and P. densiflora (PD). For QA, no significant difference was observed in the root decomposition rates across the treatments at any collection time. However, for PD, the 0-2mm roots exhibited the highest decomposition rate under the double-layer treatment (×2) and the lowest under the no-layer treatment (×0). No significant treatment effect was observed for the 2-5mm roots of PD. For the leaves, both species showed the highest decomposition rate under the double-layer (×2) treatment and the lowest decomposition rate under the no-layer (×0) treatment. These results suggest that the manipulation of the litterfall layer impacts the soil environment of forest ecosystems. This study provides valuable insights into how changes in the litterfall layer affect the decomposition of roots and leaves, which could help predict future changes in forest ecosystem processes due to climate change and contribute to research on carbon cycling.

Keyword: decomposition, environmental manipulation, litterbag, litterfall layer

Acknowledgement: This work was supported by the National Research Foundation of Korea(NRF) grant funded by the Korea government(MSIT). (No. 2021R1A2C201017812)