Effects of AMF inoculation on plant-soil ecological stoichiometry and nutrient recovery in Shendong mine

Abstract

Vegetation restoration and microbial reclamation of mining subsidence area is the key spot to construct green mine.The effects of Arbuscular Mycorrhizal Fungi (AMF) and re-vegetation types on the ecological chemometric characteristics of the plant-litter-soil continuum and leaf nutrient resorption are still unclear, but are important for illuminating nutrient cycling and sustainable development after ecological restoration in arid coal mining subsidence areas in Northwest China. Five types of restored vegetation and the 0～10 cm soil of the corresponding vegetation were selected for study in the reclamation of 10 years of inoculation with AMF and the control area—Amorpha fruticosa, Hippophae rhamnoides, Xan-thoceras sorbifolium, Cerasus humilis and Cerasus szechuanica.The intention was to explore the influences of inoculum and re-vegetation type on C, N and P contents and ecological stoichiometric ratios, nutrient recovery rates, and nutrient limitation within the plant-litter-soil continuum. Compared with the national level, the average nutrient content of the five restored vegetation organs showed the characteristics of higher C, lower P and lower N. The decomposition of the litter and plant growth were limited by the deficiency of soil N.Redundancy analysis indicates that the main soil factors affecting plant ecological stoichiometry were soil organic carbon, P, easily extracta-ble-glomalin-related soil protein and positive correlation between soil nutrients and leaf nutrient resorption mediated by mycorrhizae.AMF inoculation enhanced plant and soil nutrient content, N and P recovery rates and C:N, reduced vegetation N:P, which in turn alleviated plant N limitation, increased plant growth rate supporting the restoration of revegetation and promoting nutrient cycling along the continuum.On the other hand, the nutrient content, stability and growth rate of the inoculated nitrogen-fixing vegeta-tion in different artificially reconstructed vegetation of Amorpha fruticose and Hippophae rhamnoides were high. Ecological stoichiometry and nutrient recovery characteristics of the plant-litter-soil continuum pre-dicted soil nitrogen-limited sustainable ecological restoration in subsidence areas, while inoculation with AMF promoted the potential of sustainable ecological restoration in subsidence areas.

Keywords

• coal mining subsidence sites
• arbuscular mycorrhizal fungi (amf)
• ecological restoration
• ecological stoichiometry