The spatially heterogeneous distribution of soil nutrients is ubiquitous in terrestrial ecosystems and has been shown to promote the performance of plant communities, influence species coexistence, and alter ecosystem nutrient dynamics. Plants interact with diverse soil microbial communities that lead to an interdependent relationship (e.g., symbioses), driving plant community productivity, belowground biodiversity, and soil functioning. However, the potential role of the soil microbial communities in regulating the effect of soil nutrient heterogeneity on plant growth has been little studied. Here, we highlight the ecological importance of soil nutrient heterogeneity and microorganisms and discuss plant nutrient acquisition mechanisms in heterogeneous soil. We also examine the evolutionary advantages of nutrient acquisition via the soil microorganisms in a heterogeneous environment. Lastly, we highlight a three-way interaction among the plants, soil nutrient heterogeneity, and soil microorganisms and propose areas for future research priorities. By clarifying the role of soil microorganisms in shaping the effect of soil nutrient heterogeneity on plant performance, the present study enhances the current understanding of ecosystem nutrient dynamics in the context of patchily distributed soil nutrients.

Aims: Many wetlands are polluted with both nutrients and toxic metals and vegetated largely by clonal plants. We hypothesized that eutrophication and clonal integration can increase phytoremediation of toxic metal pollution by increasing plant growth, even under the stress imposed by toxicity.Methods: To test this hypothesis, single ramets of the common, widespread, floating, stoloniferous plant Pistia stratiotes L., were grown for 42 days at two levels of nutrient availability with and without 0.6 mg L−1 cadmium. Ramets were either severed from their vegetative offspring to prevent clonal integration or left connected, and severed offspring were either removed to eliminate intraclonal competition or left in place.Important Findings: Plants subjected to cadmium addition accumulated almost twice as much dry mass if given the higher nutrient level, due mainly to a doubling of the number of clonal offspring. Severance had little effect on the final mass of the parent plus offspring ramets. Removing offspring following severance had no effect on the final mass of the parental ramet in the presence of added cadmium, but it did increase the final mass of the parent in the absence of cadmium. These results support the hypothesis that eutrophication can increase remediation of toxic metal pollution by aquatic macrophytes but provided no evidence that clonal integration can affect remediation. Species such as P. stratiotes may help remediate co-pollution of wetlands with toxic metals and nutrients, and fragmentation of clones may not affect their remediation capacity.