CAREER: Disentangling the effect of land use intensification on soil weathering processes

Soils are at the center stage for most social challenges and solutions for food, energy, and climate crises. Soil performs many functions that are critical to healthy ecosystems and communities, one of which is the provision of nutrients. Out of the 18 essential element nutrients for plants, animal, and human diets, 16 come directly from the breaking down of soil minerals (i.e., weathering ).

Major nutrient elements like phosphorous, calcium, zinc, and iron are fundamental for productive ecosystems and prosperous communities. Yet mineral weathering processes that provide these nutrients are greatly understudied, especially in working agricultural lands. The latter poses a significant knowledge gap and scientific challenge, considering that about half of the USA's land is used for agriculture, 98% of the world’s food comes from farmed soils, and 50% of the worldwide population does not consume enough nutrients.

This project aims to provide insights into the processes controlling mineral weathering in agricultural soils across soil types and climatic gradients from Puerto Rico to Illinois. In addition, the project will create an education and outreach program to promote, engage, and help retain students to pursue careers in soil sciences by enhancing and leveraging existing resources and creating a soil-art-based educational program to attract K -12 students into STEM professions.

The proposed research aims to improve our fundamental understanding of land use intensification's effect on mineral weathering processes, weathering patterns, bicarbonate production, and secondary mineral formation. This project will 1) determine the dominant weathering patterns and quantify weathering and erosion rates due to agricultural intensification across soils and environmental gradients; 2) quantify the effect of management intensification on weathering rates using in-situ mineral weathering mineral incubations across environmental gradients in representative croplands of Texas; 3) determine early human-driven changes in weathering process dynamics in simulated agroecosystems mesocosms under controlled conditions.

This project will bridge the gap between temporal and spatial scales by quantifying weathering in agricultural soils using various laboratory, field, and experimental approaches across different environments. An improved understanding of agriculture's impact on mineral weathering has far-reaching implications across multiple socio-ecological domains.

By deepening our understanding of these impacts, land managers can redesign soil practices to safeguard nutrient resources, which will be crucial for maintaining and increasing crop yields to meet the demands of a growing global population and balancing environmental conservation and climate resiliency goals.

This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.