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Interactions between arbuscular mycorrhizal fungi (AMF) and plants are sensitive to a myriad of underlying factors, including soil chemistry and land-use disturbances. Here we address how two grassland ecosystems (Ozark glades vs. tallgrass prairies) in south-central USA have been impacted by legacy effects from land-use disturbances (e.g., fire suppression in glades and tillage, fertilizer, row cropping, and grazing in prairies) and geological substrate (acidic versus calcareous bedrock). We surveyed AMF on the roots of two native generalist host species [Ruellia humilis Nutt. and Schizachyrium scoparium (Michx.) Nash] as well as plants randomly selected from the plant community. Glades on calcareous bedrock had a higher pH than those on acidic bedrock, and AMF communities on all three root sample types varied between acidic and calcareous bedrock locations. In prairies, both bedrock types had a similar soil pH, and AMF communities on all three root sample types varied across remnant and disturbed prairies. Shifts in AMF composition across land-use history included shifts in dominant AMF genera, and some unique rare AMF taxa were restricted to only calcareous glades or remnant prairies. Our findings suggest that reseeding prairie plant communities on cultivated lands does not restore AMF communities. Restoration projects need to address the soil environment and community. [ABSTRACT FROM AUTHOR]

The methods employed in a restoration can impact the resulting plant community. This study investigated the effect of restoration method on several indices of plant community structure by comparing two restoration methods conducted over an 8-year period to a naturally colonized postagricultural field and a remnant grassland. The restoration methods included (1) distributing seed over fallow fields and (2) planting established seedlings in combination with seeding a fallow field. We found greater plant community resemblance (i.e., floristic quality, native species richness, and native diversity) to remnant grasslands with the introduction of seedlings during the first 4 years of restoration. There was also a negative correlation between the native plant diversity and the density of exotic plants in the restoration. This relationship suggests that introducing native plants in postagricultural fields may represent an effective management strategy to reduce exotic plant density. [ABSTRACT FROM AUTHOR]