Work

Kinetic and Thermodynamic Characteristics of Soil Enzymes in Pure and Mixed Forest Samples on the Loess Plateau of China

Year: 2024

Type: article

Abstract: ABSTRACT Background Soil enzymes are key to predicting nutrient availability and forest fertility. Aims We aimed to evaluate the influence of forest type on the kinetic and thermodynamic characteristics of soil enzymes. Methods Soils were sampled at 0–10 and 10–20 cm depth from two pure forests (Pinus tabulaeformis [PTF] and Quercus acutissima [QAF]) and a mixed forest of PTF and QAF (MF) on the Chinese Loess Plateau. Kinetic parameters (maximum enzyme activity [Vmax], half‐saturation constant [Km], and enzyme efficiency [Kcat]) and thermodynamic parameters (temperature coefficient [Q10] and activation energy [Ea]) of β‐1,4‐glucosidase (BG), β‐1,4‐N‐acetylglucosaminidase (NAG), l‐leucine aminopeptidase (LAP), and alkaline phosphatase (AP) were determined. Results Forest type exerted significant influence on soil enzyme kinetic parameters. The Vmax and Kcat values of BG, NAG, and AP in PTF of 0–10 cm soil depth were 42.54% and 59.22%, 77.18% and 23.08%, and 62.82% and 58.21% higher than that in MF, respectively. The Vmax of AP and Kcat of NAG in PTF of 10–20 cm depth were 34.61% and 39.90% higher than that in MF. The soil enzyme thermodynamic parameters were significantly influenced by forest type and soil depth. At 0–10 cm depth, low values of Q10–Vmax and Q10–Km of BG, Q10–Vmax and Q10–Kcat of NAG, and Ea of BG and NAG were found in PTF. At 10–20 cm depth, low values of Q10–Vmax, Q10–Kcat, and Ea of BG and NAG were found in MF. Conclusions PTF was more effective in promoting soil enzymatic reactions, especially in surface soil. MF improved subsoil enzyme thermal stability and reduced temperature sensitivity. The study showed that pure and mixed forests affect soil enzyme characteristics differently, with soil depth as a key factor.

Source: Journal of Plant Nutrition and Soil Science

DOI: 10.1002/jpln.202400242

Authors: Lie Xiao, Xuxu Min, Zhanbin Li, Peng Li

Institution: Xi'an University of Technology

Language: English

Topic: Soil Carbon and Nitrogen Dynamics

Subfield: Soil Science

Field: Agricultural and Biological Sciences

Domain: Life Sciences

SDGs: Life on land, Zero hunger

Open Access status: bronze

Funders: National Natural Science Foundation of China, Education Department of Shaanxi Province, National Key Research and Development Program of China