Date of Award
Winter 2025
Project Type
Thesis
Program or Major
Earth Sciences
Degree Name
Master of Science
First Advisor
Julie G. Bryce
Second Advisor
Robert Letscher
Third Advisor
Louis S. Tisa
Abstract
Enhanced rock weathering (ERW) is a carbon dioxide removal strategy aimed at taking advantage of the natural silicate weathering process and combining it with agricultural practices. ERW has thus far largely been studied in crops like corn and soy. Few studies have pursued longer-lived agricultural products like sugar maple trees, which, given their frequent association with mycorrhizal fungi, also serve to contribute to the knowledge gap about the potential opportunity for mycorrhizae, essential members of the soil microbiological community, to contribute to ERW practices. This study focuses on quantifying the element mobilization occurring in seedling systems from silicate rock weathering and determining how lithologic amendment, lithologic composition, silicate amendment location within the soil column, presence of mycorrhizal fungi, and plants factor into mobilizing elements, ERW potential, and ERW practices. Sugar maple seedlings were grown in greenhouse conditions and monitored over a 100-day growth period. Monthly soil solution samples, together with bioavailable soil nutrients for determining bioavailable elements, were collected to assess element mobilization. Chemical abundances, together with biomass data and plant health assessments, were also undertaken. Mycorrhizal fungi enhanced nutrient transfer in the soil solution samples for Mg, P, and Ca, demonstrating their role in rock weathering. Felsic amendments generally resulted in greater elemental enrichment than mafic amendments, although mafic amendments released more Fe and Mn. Shifts in pH demonstrated carbonate dissolution early in the experiment and shifted later to silicate rock weathering. These findings demonstrated the complexity of plant, fungi, and rock interactions in nutrient cycling and their potential for ERW. Future work will integrate plant tissue chemistry to quantify plant uptake.
Recommended Citation
Gianturco, Sarah Ruth, "Enhanced Silicate Weathering by Sugar Maples Across Varied Lithologies" (2025). Master's Theses and Capstones. 2047.
https://scholars.unh.edu/thesis/2047