A simulated ecological restoration of bare cut slope reveals the dosage and temporal effects of cement on ecosystem multifunctionality in a mountain ecosystem

J Environ Manage. 2023 Jan 1;325(Pt B):116672. doi: 10.1016/j.jenvman.2022.116672. Epub 2022 Nov 5.

Abstract

Cement is a critical building material used in the restorations of bare cut slopes. Yet, how cement affects ecosystem's functions and their undertakers remains elusive. Here, we revealed the dosage and temporal effects of cement on plant and soil traits, extracellular enzymes, greenhouse gas fluxes and microbiome using simulation experiments. The results showed that soil pH increased with the cement content at 1st day but relatively constant values around 7 to 7.5 were detected in the flowing days. The β-1,4-glucosidase, phenol oxidase, leucine aminopeptidase and acid phosphatase showed high activities under high cement content, and they generally increased with the cultivations except for acid phosphatase. CH4 fluxes at 16th day were less than zero, and they increased to peak around at 37th to 44th days followed by decreasing until reaching to relatively stable fluctuations around 0. Despite of decrease patterns, N2O fluxes stayed around zero across the temporal gradient except for the maximum around at 30th day in 2%, 5% and 8% cement treatment. Microbial diversity decreased with the cement content, in which there were a recovery trend for bacteria. By integrating above- and belowground ecosystem traits into a multifunctionality index, we identified a potential optimum cement content (11%). PLSPM showed that multifunctionality was affected by the shifts in soil bacterial community, enzyme activity and greenhouse gases while these components were effected by other environmental changes resulted from cement. Our results demonstrate that cement determines multifunctionality through mediating microbial community and activity, providing new insights for designing in situ experiments and ecological restoration strategies for bare cut slopes.

Keywords: Cement; Cut slope soils; Microbial community structure and activity; Multifunctionality.

MeSH terms

  • Acid Phosphatase
  • Bacteria
  • Ecosystem
  • Greenhouse Gases*
  • Microbiota*
  • Soil / chemistry
  • Soil Microbiology

Substances

  • Soil
  • Greenhouse Gases
  • Acid Phosphatase