Honors Theses and Capstones

Date of Award

Spring 2017

Project Type

Senior Honors Thesis

College or School

COLSA

Department

Natural Resources and the Environment

Program or Major

Environmental Science: Soil & Watershed Management

Degree Name

Bachelor of Science

First Advisor

Alexandra Contosta

Abstract

The expansion of local agriculture in the New England region is putting increased pressure on farmers to expand their arable land base. While clear-cutting is a traditional method of converting forested land to agriculture, it is known for having adverse ecological impacts. To minimize these impacts, farmers can create a silvopasture which incorporates a portion of the original forest canopy into pastures or crop fields. This study evaluates the impact of land-use changes for agriculture on soil nitrogen (N) retention. In particular, this study investigates the differences in soil N turnover, gaseous loss, and aqueous loss among an established forest, established pasture, clear-cut converted pasture, and converted silvopasture systems over a 30day incubation period. We found significant differences in N mineralization, immobilization, and denitrification among treatments, with evidence that a forest-to-silvopasture conversion can successfully support soil N retention within the first two years of implementation. This may have been due to the presence of coarse woody debris inputs from forest cutting and its effect on the soil carbon (C) to N ratio. Nitrogen retention in silvopastures may also result from partial preservation of the forest canopy. Our results suggest that farmers looking to expand their agricultural land base through forest clearing may be able to use silvopastures for as a way of retaining soil nutrients while at the same time putting land into production.