Successional dynamics of soil fungal diversity along a restoration chronosequence post‐coal mining

Abstract

Soil disruption from open-cut mining practices can adversely impact microbial communities and the ecosystem services that they mediate. Despite this, assessment of impacts of soil disruption, and the subsequent recovery of microbial communities is rarely studied. Monitoring of ecological restoration success on mine sites has traditionally focused on vegetation; however, most plants rely, at least in part, on associations with soil fungi for enhanced nutrient and water acquisition. Here, we used highthroughput phylogenetic marker gene sequencing to characterize the diversity of soil fungal communities along a restoration chronosequence ranging from 3 to 23 years at a rehabilitated mine site. We used nonmined analogue sites as a baseline for comparative purposes and examined the associations of soil fungal communities with soil physicochemical and aboveground vegetation variables. Fungal richness on rehabilitated sites was significantly larger than on nonmined sites, suggesting that mixing of topsoil during stockpiling resulted in a composite microbial community. Fungal community composition was significantly influenced by edaphic variables and the length of rehabilitation, with mined sites becoming more similar to nonmined sites over time. Fungal populations associated with ectomycorrhizae were relatively more abundant than those associated with arbuscular mycorrhizae and declined in response to disturbance, but recovered over time on the woody dominated sites indicating a strong coupling of these fungi with aboveground vegetation. Our data indicate that soil fungal diversity is a useful bioindicator of soil restoration in mined sites and may complement more traditional vegetation-based surveys.

Temporal dynamics in biotic and functional recovery following mining

“…Increased soil pH under rehabilitation would favour fungal over bacterial decomposition (Angel et al, 2013; Tedersoo et al, 2014), which accords with both the greater fungal biomass with time since rehabilitation (Figure S8.2) and the increase in AMF biomass with increasing pH (Figure S8.5). We also found that fungal diversity was greater in soils at reference (1,088 ± 134, M ± SD ) than rehabilitated (974 ± 210) sites, unlike studies from other mine site restoration studies (Ngugi et al, 2019). Fungi are critically important in the restoration process because they recycle organic matter, improve soil structure, ameliorate metal tolerance in plants, and enhance water holding capacity (Delgado‐Baquerizo et al, 2019; Ngugi et al, 2019).…”

“…We also found that fungal diversity was greater in soils at reference (1,088 ± 134, M ± SD) than rehabilitated (974 ± 210) sites, unlike studies from other mine site restoration studies (Ngugi et al, 2019). Fungi are critically important in the restoration process because they recycle organic matter, improve soil structure, ameliorate metal tolerance in plants, and enhance water holding capacity (Delgado-Baquerizo et al, 2019;Ngugi et al, 2019). Future work needs to further investigate how to trigger the restoration of soil microbial diversity, a major driver of ecosystem functioning, to help in achieving maximum levels of ecosystem recovery after disturbance.…”

Living Fungi in an Opencast Limestone Mine: Who Are They and What Can They Do?

“…On the other hand, several studies have been conducted on fungal community response to restoration chronosequence. Whlist Ngugi et al [ 62 ] demonstrated that fungal communities eventually became more similar to the reference condition over time, Kane et al [ 63 ] found no obvious trend in fungal diversity toward the reference forest. However, both investigations found that the fungal community was mostly shaped by edapic variables [ 62 , 63 ].…”

Insight into the Characteristics of Soil Microbial Diversity during the Ecological Restoration of Mines: A Case Study in Dabaoshan Mining Area, China

“…The ecological restoration process of mines is relatively long, and it is very necessary to monitor and evaluate the ecological characteristics of the restoration process. In the early stage, the evaluation and monitoring of the restoration effect of mining area mostly depend on the physicochemical properties of aboveground vegetation and soil [25,26]. Although soil microorganisms were affected by mining activities and had a regulatory role in ecosystem function, they were rarely monitored in prior research studies [27,28].…”