Table 1 Summary of key definitions of plant–soil feedbacks (PSF) based on research objectives and nature of PSFs experimental system
From: Climate change-driven shifts in plant–soil feedbacks: a meta-analysis
Plant–soil feedbacks (PSFs) | |||
|---|---|---|---|
Context | Interpretation | Calculation | References |
One of the first experimental studies of PSFs and their role in population dynamics | Individual plants, or population of plants, affect the composition of the soil community in ways that affect the growth of the same plant or population Most studies follow this definition although experimental designs differ among studies and interpretations vary accordingly (see below) | PSF = Log (biomass of an individual or population of Species A when grown in soil conditioned by Species A/biomass of individual or population of Species A when grown in soil conditioned by another species) | Bever et al. (1997) |
More recent definition often used to assess impacts of global changes (e.g., climate change, nutrient deposition) | Plant–soil feedback is a two-phase ecological concept focused on how plants modify their growing environment by altering biotic (e.g., soil biota) and abiotic (e.g., soil physicochemical properties, stoichiometry) factors which in turn influence the growth and development of individuals of the same species or other species subsequently growing in the same soil Such PSFs can be measured at the species or community level, with resulting differences in interpretation | PSF = Log (biomass of Species A or Community A when grown in soil conditioned by the same species or community/biomass of Species A or Community A when grown in soil conditioned by another species or community) | van der Putten et al. (2016) |
PSF interpretation at the species level | Positive and negative PSFs occur when biomass production of a given species is higher or lower in soil conditioned by an individual of the same species, respectively. Positive PSFs will result in species becoming more dominant, whereas negative PSFs will result in species becoming less dominant | As above (1st calculation) | Hassan et al. (2021) |
PSF interpretation at the community level | Positive and negative PSFs occur when biomass production of a community is higher or lower in soil conditioned by the same community, respectively. Positive PSFs will result in more stable communities, whereas negative PSFs will result in communities becoming less stable | As above (2nd calculation) | Hassan et al. (2021) |
PSFs driven by the soil biotic community (also known as direct or absolute PSFs) | PSFs focussing on the effects of the soil biota can be quantified by comparing the performance of an individual plant species grown in soil conditioned by the same species with biomass produced when grown in a sterile soil | PSF = Log (biomass of Species A in soil conditioned by the same species/biomass of Species A in sterile soil) | |