Plant genotypic variation and intraspecific diversity trump soil nutrient availability to shape old‐field structure and function

Abstract

Summary Individual plant genotypes as well as genotypic diversity can shape the structure and function of ecosystems; however, the abiotic environment may modify these genotypic influences on ecosystem‐level responses. To explore how the interactions between plant genotype, genotypic diversity and soil nutrient availability affect the structure and function of a temperate grassland ecosystem, we manipulated the genotypic diversity of a common perennial herbaceous plant, Solidago altissima (single genotype monoculture and diversity plots) and soil nutrient availability (+nitrogen, +phosphorus, +nitrogen and +phosphorus, unmanipulated control) in a common garden setting. We tracked temporal changes in ecosystem structure (e.g. leaf area index and net primary productivity) as well as a variety of ecosystem functions (e.g. net ecosystem carbon and water exchange and soil carbon efflux) over a growing season. We found that variation in plant genotype identity consistently shaped ecosystem structure (above‐ground net primary productivity) while it inconsistently altered several ecosystem functions across time. For instance, variation in plant genotype identity influenced net ecosystem carbon dynamics early in the growing season while it influenced water dynamics later in the growing season. The strength of the relationship between genotypic diversity and ecosystem function declined over the season and the relationship between ecosystem structure (above‐ground net primary productivity) and function (net ecosystem carbon and water exchange) varied across treatments. Overall, there was a strong correlation between ecosystem structure and function across monoculture genotype plots but a weak relationship between ecosystem structure and function across mixed genotype plots. Surprisingly, soil nutrients did not influence ecosystem structure and had minimal impacts on carbon and water flux. Our data suggest that plant genetic variation, and to some extent plant genotypic diversity, strongly influence ecosystem structure and function in an old‐field ecosystem, but nutrient availability did not directly or interactively influence ecosystem structure or function. A http://onlinelibrary.wiley.com/doi/10.1111/1365-2435.12792/suppinfo is available for this article.

Mixing source populations increases genetic diversity of restored rare plant populations

“…Research supports the use of genetically diverse plant material for restoration efforts because genetically diverse populations are generally more resilient to disease, stress, and climatic extremes (Burdon ; Reusch et al ; Guarino et al ), more likely to persist and spread (Hughes & Stachowicz ; Crawford & Whitney ), and support more ecosystem services (Crutsinger et al ; Souza et al ). Yet in practice many reintroduced plant populations have lower genetic diversity than remnant populations (Fant et al ; Neale ).…”

Intraspecific functional trait structure of restoration‐relevant species: Implications for restoration seed sourcing

“…and key ecosystem functions like productivity (Abbott, Grosberg, Williams, & Stachowicz, 2017) and nutrient cycling (Souza, Stuble, Genung, & Classen, 2017) are increasingly well documented.…”

“…Positive relationships between intraspecific genetic diversity and key ecosystem functions like productivity (Abbott, Grosberg, Williams, & Stachowicz, 2017) and nutrient cycling (Souza, Stuble, Genung, & Classen, 2017) are increasingly well documented. Intraspecific genetic diversity can impact ecosystem functioning via niche partitioning driven by complementarity among genotypes (Raffard, Santoul, Cucherousset, & Blanchet, 2019).…”

A direct comparison of the effects and mechanisms between species richness and genotype richness in a dominant species on multiple ecosystem functions

“…Over years, most studies have confirmed that species richness has significant positive direct effects on a single ecosystem function such as biomass production (van der Plas, 2019). Meanwhile, there is increasing evidence that genotype richness plays an important role in affecting a single ecosystem function (Schweitzer et al, 2011;Souza et al, 2016).…”