The Role of Arbuscular Mycorrhizal Fungi in Urban Brownfield Soils

AMF are symbionts to a majority of terrestrial plants and can improve plant nutrient uptake, water relations, and stress tolerance. This study evaluated the effects of AMF in heavy metal contaminated soils via a growth chamber experiment to determine the interactions between soil and arbuscular mycorrhizal fungi (AMF) affecting plant growth. Rye grass was grown in two contaminated soils from Liberty State Park, an urban brownfield, and one non-contaminated commercial soil, to which half of the treatments received AMF inoculum. Dried plant biomass, root:shoot ratio, and soil phosphatase activity were measured at the completion of the experiment. Soil contamination was seen to decrease plant biomass. Across all soil types, AMF facilitated plant growth. Furthermore, a significant interaction between AMF and soil type was seen in average shoot mass. Contaminated soil led to an increase in root AMF colonization compared to non-contaminated soil. Root:shoot ratio and soil phosphatase activity were affected by soil type but not AMF. These results emphasize the degree to which soil type affects plant primary production and soil functioning, as well as the role of AMF in facilitating plant growth in urban brownfield soils