Changes in the soil microenvironment during ecological restoration of forest parks in megacities

Abstract

Forest parks in megacities are pivotal in boosting biodiversity, purifying air, and offering essential green areas for community leisure and mental health amidst the hustle and bustle of cities. Yet, these vital oases encounter severe difficulties, including habitat degradation, contamination, and urbanization pressures, jeopardizing their preservation and the crucial ecological advantages they offer. The soil’s characteristics and its microbial inhabitants are fundamental in the cycling of nutrients and the well-being of plants, positioning them as central elements in restoration efforts. Nonetheless, the complex interplay among plant, soil, and microbial relationships during the restoration of forest ecosystems in megacities is still not well comprehended. This study aimed to investigate the interactions between plant-soil-microbial dynamics in different ecological restoration modes and construct assessment systems to evaluate the quality of restoration modes in the forest parks. The study identified a total of 25 distinct types of forests damaged by three main factors (farmland, highway, and quarrying) in Chongqing Taisiya Forest Park, and found that long-term natural restoration significantly increased soil properties in these forests. Additionally, an in-depth microbial sequencing analysis showed that Proteobacteria and Ascomycota were the major bacterial and fungal phyla dominant in the restoration process in the urban forests. Further correlation analysis showed that soil microbial diversity positively correlated with plant diversity, with a stronger correlation observed for bacterial communities compared to fungi. The comprehensive evaluation index results for the different forest types revealed varying degrees of restoration success. Collectively, our findings underscore the importance of forest attributes and soil microbial diversity in forest ecosystem restoration and provide valuable insights for designing effective restoration strategies in similar ecosystems.

Keywords

• Forest biodiversity
• Soil microbiome
• Ecological restoration
• Assessment systems
• Megacity forests