Chin J Plant Ecol ›› 2021, Vol. 45 ›› Issue (青藏高原高寒草地:格局与过程): 0-0.DOI: 10.17521/cjpe.2020.0169

   

The effect of soil organic matter chemical compositions on soil protease and urease activity of alpine grassland soils in Northern Tibet, China

Shuqin Ma1,Ziwei Wang2,Youchao Chen3,Xuyang Lu2   

  1. 1. College of Tourism, Henan Normal University
    2. Institute of Mountain Hazards and Environment (IMHE), Chinese Academy of Sciences
    3. Wuhan Botanical Garden, Chinese Academy of Sciences
  • Received:2020-05-25 Revised:2020-07-30 Online:2021-04-20 Published:2020-08-07
  • Contact: Xuyang Lu

Abstract: Aims Soil enzymes play an important role in the process of soil nutrient transformation. The main purpose of this study is to explore the soil organic matter chemical compositions and its effect on soil protease and urease activity in alpine grasslands in Northern Xizang, China. Methods The pyrolysis Gas Chromatograph/Mass Spectrometer (Py-GC/MS) was used to obtain the chemical compositions of soil organic matter, and to analyze the relationships between soil chemical compositions and soil enzyme activity from five alpine grasslands, including alpine meadow, alpine grassland, alpine meadow grassland, alpine desert grassland and alpine desert in Northern Xizang, China. Important findings The results showed that the enzyme activities among five alpine grassland soils (0-15 cm) were different. The urease activity in the soil of alpine desert steppe was significantly higher than protease, while the difference between the urease and protease activities of other types of alpine grassland did not reach statistical significance. The difference of soil protease activity was significant difference among five alpine grassland types, while the difference of soil urease activity was not significant. The correlation analysis showed that the protease activity was closely related to the relative abundance of alkanes, alkenes and aromatics in soil organic matter and the ratio of furfural to pyrrole. Nevertheless, the correlation relationships between urease activity and soil organic matter chemical compositions were not significant. The results indicated that alpine grassland type and soil organic matter chemistry were the key factors affecting soil protease activity rather than soil urease activity, hence the urease activity of alpine grassland soils and its influencing factors needed further study.

Key words: Alpine meadow, Alpine steppe, Soil organic matter chemistry, Enzyme activity, Pyrolysis Gas Chromatograph/Mass Spectrometer (Py-GC/MS)