Litter addition and understory removal influenced soil organic carbon quality and mineral nitrogen supply in a subtropical plantation forest

• Published in: Plant and soil Vol. 460; no. 1-2; pp. 527 - 540
• Main Authors: Fang, Xiang-Min, Wang, G. Geoff, Xu, Zhi-Jun, Zong, Ying-Ying, Zhang, Xiu-Lan, Li, Jian-Jun, Wang, Huimin, Chen, Fu-Sheng
• Format: Journal Article
• Language: English
• Published: Cham Springer International Publishing 01.03.2021; Springer; Springer Nature B.V
• Subjects: Biomedical and Life Sciences; Carbon content; Cellobiase; China; Ecology; Environmental aspects; Forest management; Forests and forestry; Glucosidase; Hydrolase; Life Sciences; Litter; Litter (Trash); Mineralization; N-Acetylglucosaminidase; Nitrification; Nitrogen; Nitrogen in the body; Organic carbon; Organic soils; Plant Physiology; Plant Sciences; Plantations; Regular Article; Soil dynamics; Soil fertility; Soil improvement; Soil Science & Conservation; Soils; Topsoil; Understory; β-Glucosidase; China; Litterfall and understory manipulation; SOC quality; C; N mineralization; δ; Particle-size fractions
• ISSN: 0032-079X; 1573-5036
• DOI: 10.1007/s11104-020-04787-8

Aims Aboveground litter inputs have been modified by global changes in plantation forests, where understory management is also prevalent, which may alter soil fertility and stand productivity. This study aimed to quantify the specific roles of litter and understory in affecting soil carbon (C) and nitrogen (N) dynamics. Methods A field experiment was established with four treatments, namely, litter addition (LA), understory removal (UR), litter addition and understory removal (LA + UR), and a control, in a subtropical Cunninghamia lanceolata plantation. Topsoil δ 13 C, organic C concentration, storage and decomposition, mineral N, N mineralization, and C and N hydrolase activities were analyzed. Results Litter addition significantly increased soil organic C, macro-particulate organic C (macro-POC) and mineral N at a 0–5 cm depth, but decreased δ 13 C macro-POC at 0–5 cm and 5–10 cm depths. Understory removal significantly increased soil NH 4 + -N, the rates of nitrification and net N mineralization as well as the soil organic C respiration rate at the two depths, while it decreased the C storage in bulk soil, especially in mineral protected pools. The activities of β-glucosidase and β-N-acetylglucosaminidase increased with litter addition and understory removal, respectively. Conclusions Litter addition tends to improve soil C quantity and quality due to fresh organic C inputs, while understory removal helps increase the N supply via the acceleration of N mineralization and the absence of understory plant uptake.