Changes in Soil Microbial Community along a Chronosequence of Perennial Mugwort Cropping in Northern China Plain

Abstract

Perennial cropping plays a vital role in regulating soil carbon sequestration and thus mitigating climate change. However, how perennial cropping affects the soil microbial community remains elusive. Using a field investigation, this study was conducted to examine the effects of mugwort cropping along a chronosequence (that is, wheat–maize rotation, 3-year, 6-year, and 20-year mugwort cropping) on a soil microbial community in temperate regions of Northern China. The results showed that the highest total, actinomycete, and fungi phospholipid fatty acids (PLFAs) were found in the 3-year mugwort cropping soils. By contrast, all PLFAs of microbial groups were lowest in the 20-year mugwort cropping soils. Network complexity of the soil microbial community under each of the three durations of mugwort cropping was greater than that under the wheat–maize rotation. Changes in total nitrogen and phosphorus content as well as the ratio of ammonium nitrogen to nitrate nitrogen primarily explained the variations in soil microbial community along the mugwort cropping chronosequence. Our observations highlight the contrasting responses of soil microbial community to short-term and long-term mugwort cropping compared with conventional rotations and would have critical implications for sustainable agricultural management under perennial cropping in temperate regions.