Seasonal variation in soil microbial biomass carbon and nitrogen in an artificial sand-binding vegetation area in Shapotou, northern China

Abstract

In this study,seasonal variation characteristics of surface soil microbial biomass carbon(MBC)and soil microbial biomass nitrogen(MBN)of an artificial vegetation area located in Shapotou for different time periods were studied using the chloroform fumigation method,and the results were compared with those of near-natural vegetation areas and mobile dunes.Results showed that the MBC and MBN levels in the 0–5 cm soil layer were higher in autumn than in summer and spring.As the prolongation of vegetation restoration raised the MBC and MBN levels in summer and autumn,no clear variation was found in spring.However,the MBC and MBN in 5–20 cm had no obvious seasonal variation.During summer and autumn,the variation trend of MBC and MBN in the vertical direction was shown to be0–5>5–10>10–20 cm in the vegetation area,while for mobile dunes,the MBC and MBN levels increased as the depth increased.The natural vegetation area was shown to possess the highest MBC and MBN levels,and yet mobile dunes have the lowest MBC and MBN levels.MBC and MBN levels in artificial sand-binding vegetation increased with the prolongation of vegetation restoration,indicating that the succession of sand-binding vegetation will result in the accumulation of soil carbon and nitrogen,as well as the restoration of soil fertility.