Hana Consterdine Receives Recognition for Her Work On the Soil Carbon Accrual Project

by CRARS staff member Sheryl Karas. M.A.

Congratulations to Hana Consterdine who won first place for her Poster Session presentation in the 39th Annual Student Research Symposium on March 6, 2025. This event, hosted by the Office of Graduate Studies, was designed to recognize academic excellence in student scholarly research. This year’s event was sponsored by Instructionally Related Activities and the Office of the Provost and saw record participation: 110 submissions, 117 student presenters, and nearly 200 audience members!

That is impressive enough but Hana is an undergraduate in Environmental Science (BSc) and won in a category that combined graduates (MSc) and undergraduates (BSc). She is conducting her Honors Research in Environmental Science with faculty mentor Sandrine Matiasek comparing water quality in soils managed according to conventional or regenerative agricultural practices as part of the CRARS Soil Carbon Accrual Project(opens in new window). Hana’s poster presentation, “Exploring Nitrate Transport in Surface and Soil Water Across Agricultural Practices,” discussed preliminary findings related to nitrate concentrations in surface and soil waters.

Nitrogen is commonly used in agricultural fertilizers, but excess nitrogen, particularly in the form of nitrate, causes contamination in surface runoff and groundwater. This is associated with damage to rivers, lakes and coasts,higher carbon emissions for drinking water treatment, and serious impacts on human health.  Regenerative agricultural practices could reduce nitrogen runoff and its associated environmental and health impacts.

In this research project, nitrate concentrations in surface and soil water were monitored and compared in a regenerative agriculture field and a conventional one at the Chico State University Farm. The conventional field was farmed using full tillage, fertilizer and pesticide use, and no ground cover. It was seeded with corn and then left bare during winter. The regenerative field employed cover crops, reduced tillage, and crop rotations. It was not left bare over the winter and was instead seeded with multispecies cover crops. Soil water was collected from 18 lysimeters across the two fields and grab samples of surface water were collected from flowing water found in each field during irrigation or storm events. Nitrate concentration was determined using colorimetric testing of filtered samples.

Preliminary results were decisive in terms of soil water: the conventional field contained higher nitrate concentrations (median: 42 mg/L) than from the regeneratively farmed field (median: 6.5 mg/L). However, there was no difference in nitrate concentrations in surface water from conventional and regenerative fields. Following fertilization events, nitrate concentrations in soil water decreased over time in the conventional field, but spiked during storms when the field was left bare after the fall harvest.

Comparing nitrate concentrations between regenerative agriculture and conventional agriculture is helpful for understanding the impact regenerative practices could have on reducing nitrate contamination in surrounding water bodies and groundwater. A better understanding of how soil water nitrate varies over time and following fertilization events could also help farmers minimize fertilizer expenses and nitrate leaching.