Soil microbial legacies influence plant survival and growth in mine reclamation

Abstract

Plants alter soil biological communities, generating ecosystem legacies that affect the performance of successive plants, influencing plant community assembly and successional trajectories. Yet, our understanding of how microbe‐mediated soil legacies influence plant establishment is limited for primary successional systems and forest ecosystems, particularly for ectomycorrhizal plants. In a two‐phase greenhouse experiment using primary successional mine reclamation materials with or without forest soil additions, we conditioned soil with an early successional shrub with low mycorrhizal dependence (willow, Salix scouleriana) and a later‐successional ectomycorrhizal conifer (spruce, Picea engelmannii × glauca). The same plant species and later‐successional plants (spruce and/or redcedar, Thuja plicata, a mid‐ to late‐successional arbuscular mycorrhizal conifer) were grown as legacy‐phase seedlings in conditioned soils and unconditioned control soils. Legacy effects were evaluated based on seedling survival and biomass, and the abundance and diversity of root fungal symbionts and pathogens. We found negative intraspecific (same‐species) soil legacies for willow associated with pathogen accumulation, but neutral to positive intraspecific legacies in spruce associated with increased mycorrhizal fungal colonization and diversity. Our findings support research showing that soil legacy effects vary with plant nutrient acquisition strategy, with plants with low mycorrhizal dependence experiencing negative feedbacks and ectomycorrhizal plants experiencing positive feedbacks. Soil legacy effects of willow on next‐stage successional species (spruce and redcedar) were negative, potentially due to allelopathy, while ectomycorrhizal spruce had neutral to negative legacy effects on arbuscular mycorrhizal redcedar, likely due to the trees not associating with compatible mycorrhizae. Thus, positive biological legacies may be limited to scenarios where mycorrhizal‐dependent plants grow in soil containing legacies of compatible mycorrhizae. We found that soil legacies influenced plant performance in mine reclamation materials with and without forest soil additions, indicating that initial restoration actions may potentially exert long‐term effects on plant community composition, even in primary successional soils with low microbial activity.

Positive and negative feedbacks drive aboveground traits in rare plant species

“…For example, Hannula et al (2021) found that while bacterial communities quickly respond to alterations in plant community composition, microbially mediated soil legacy effects remain after five months of succession. Similarly, McMahen et al (2022) found that plant succession is highly influenced by mycorrhizal dependence, with ECM plant hosts demonstrating higher seedling survival and biomass in early succession. Additionally, other belowground root-colonizing fungi such as dark septate endophytes (DSE) can enhance aboveground plant growth through increased nitrogen (N) and phosphorus (P) root absorption as well as increased root surface area (He et al 2019;Xie et al 2021).…”

“…Therefore, patterns of plant growth, reproduction, and competitive ability in current plant communities may be driven by soil-microbial changes induced by previous species no longer present or prevalent (Bever 2003, van der Putten et al 2013. Specifically, mutualistic ectomycorrhizal (ECM) fungi play an integral role in mediating the productivity and diversity of aboveground plant communities through facilitating shifts in nutrient availability as well as soil structure and stability across early, mid-, and late successional stages (Ka lucka & Jagodziński 2017;McMahen et al 2022;Zhao et al 2023Wang et al 2023. For example, Hannula et al (2021) found that while bacterial communities quickly respond to alterations in plant community composition, microbially mediated soil legacy effects remain after five months of succession.…”

Evaluasi Reklamasi di Area Pertambangan Batubara PT. PQ, Kecamatan Tanjung Kidul, Kabupaten Muara Enim, Provinsi Sumatera Selatan

“…Berkaitan dengan pentingnya peranan tanah pucuk dalam kegiatan reklamasi sesuai dengan penelitian yang dilakukan McMahen et al pada tahun 2022 yang menjelaskan bahwa penambahan volume kecil tanah pucuk yang ditargetkan dari ekosistem asli dapat meningkatkan kelangsungan hidup dan pertumbuhan bibit awal, mendorong pemulihan komunitas mikroba tanah yang terbatas, dan menjadi solusi yang menjanjikan untuk reklamasi tambang ketika ketersediaan tanah pucuk terbatas (McMahen et al, 2022).…”

The Compound Forest–Medicinal Plant System Enhances Soil Carbon Utilization

“…Soil is an important carrier of plants and is the basis of productive forestry [14]. Soil microorganisms play a critical role in regulating carbon (C) and nitrogen (N) pools and nutrient cycles by promoting the activities of terrestrial ecosystems [15][16][17]. The plant rhizosphere is a soil micro-area where plant roots and microorganisms communicate more actively [18].…”