Document Type

Thesis - Open Access

Award Date

2017

Degree Name

Master of Science (MS)

Department

Natural Resource Management

First Advisor

Jonathan Lundgren

Second Advisor

W. Carter Johnson

Keywords

agroecosystems, biodiversity, corn production, invertebrate functioning, pest management, soil health

Abstract

The adoption of regenerative farming practices is gaining traction, but the costs and benefits are not often considered on a systems level. Encouraging biodiversity and soil health is the goal of many agricultural practices used in regenerative farming; regenerative systems employ practices which abide by the two main principles of increasing biodiversity and decreasing disturbance, with the goal of encouraging ecosystem functioning to minimize inputs and maximize the productivity of a farm. I examined the management of corn (Zea mays) fields across four states in the Upper Midwest region of the United States. Regenerative systems in this study used practices such as using cover crops, not tilling, and abandoning the use of insecticide. The comparative system, a conventional management system, consisted of practices such as no cover crop or a period of bare soil, use of tillage, and use of insecticidal techniques. In this study, invertebrate community characteristics, soil health metrics, relative litter degradation rates in the presence and absence of invertebrates, yield, and profitability were assessed. Relationships among these metrics were examined, and trends between systems were also analyzed. Regenerative systems had reduced pest pressure relative to insecticide-treated conventional systems. Regenerative systems also hosted more robust epigeal and soil invertebrate communities, which were correlated with fewer pests. Regenerative systems had generally healthier soil and soil community characteristics; soil health in cornfields was positively correlated with invertebrate abundance and species richness, and there was more litter breakdown in regenerative systems. I conclude that systems which employ several farming practices focused on conserving biodiversity have healthier soil characteristics and higher biological activity in their soils. Regenerative systems had lower yields but were more profitable than conventional corn systems. The main drivers for this profit were return on grain, cost of seed (including pest management technology fees), and cost of fertilizer. Systems which employ several farming practices focused on conserving biodiversity have healthier invertebrate communities which resist pests and have healthier soil, forming the basis for more profitable crop production which is less reliant on agricultural inputs.

Library of Congress Subject Headings

Corn -- Organic farming.
Invertebrate communities.
Soil ecology.
Biodiversity.
Cover crops.

Description

Includes bibliographical references

Format

application/pdf

Number of Pages

174

Publisher

South Dakota State University

Rights

Copyright © 2017 Claire LaCanne

Available for download on Friday, May 10, 2019

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