Arid Zone Research ›› 2023, Vol. 40 ›› Issue (11): 1776-1784.doi: 10.13866/j.azr.2023.11.07

• Land and Water Resources • Previous Articles     Next Articles

Characteristics of nutrient and enzyme activity in salt-affected soils of the Qaidam Basin

HUI Rong(),TAN Huijuan,HUANG Lei,LI Xinrong()   

  1. Shapotou Desert Research and Experiment Station, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, Gansu, China
  • Received:2023-02-22 Revised:2023-06-25 Online:2023-11-15 Published:2023-12-01

Abstract:

To explore the characteristics of nutrient and enzyme activity in salt-affected soils of different degrees in the Qaidam Basin, five sampling points along the direction from Chahan Salt Lake to Kunlun Mountains were selected. The soil nutrient and enzyme activity characteristics and their correlations were analyzed. The results showed that soil salinization degree, soil depth, and their interactions significantly affected soil nutrient content and enzyme activity (P<0.05), except for soil total potassium. In soils with lower salinity, nutrient availability (except for available potassium) and enzyme activity were higher and decreased with increasing soil depth. Taking organic carbon and invertase as examples, the contents in the S5 sampling site with the lowest salinity degree were 13.83 g·kg-1 and 21.01 mg·g-1·d-1(0-5 cm), 12.85 g·kg-1 and 19.29 mg·g-1·d-1(5-10 cm), and 9.83 g·kg-1 and 12.19 mg·g-1·d-1(10-20 cm), significantly higher than those in the S1 site with the highest salinity degree, which had 8.56 g·kg-1 and 1.41 mg·g-1·d-1(0-5 cm), 8.40 g·kg-1 and 1.30 mg·g-1·d-1(5-10 cm), and 8.33 g·kg-1 and 1.26 mg·g-1·d-1(10-20 cm). The correlation analysis showed that in lower salinity areas, soil enzyme activity had a significant or extremely significant positive correlation with most soil nutrients (P<0.05). Therefore, differences were observed in the characteristics of soil nutrients and enzyme activity in salt-affected soils of different degrees in the Qaidam Basin. Soil salinization reduces the effectiveness of soil nutrients, inhibits soil enzyme activity, and reduces the decomposition rate of soil organic matter.

Key words: salinization, soil enzymes activity, soil nutrient, correlation analysis, Qaidam Basin