Project Number: 6206-12000-003-00-D
Project Type: In-House Appropriated
Start Date: Mar 11, 2012
End Date: Oct 31, 2015
Our goal in performing these research objectives is to develop a knowledge base and complementary technology to assist farmers and ranchers implement profitable, sustainable, environmentally friendly production systems. Achievement of the following research objectives during the next 2 years (24 months) will contribute to informed management of agricultural production systems based on ecosystem services, including C sequestration, increased fertilizer use efficiency, and improved water quality. Objective 1: Develop new strategies to improve crop fertilizer use efficiency for agronomic, economic and environmental benefits. Subobjective 1A: Make final determinations of runoff water quality impacts of fertilizer recommendations based on enhanced soil testing methods. Subobjective 1B: Conduct final evaluations of liquid fertilizer injection guided by GPS auto-steer technology in terms of yield and economics. Objective 2: Develop strategies to assess and manage the consequences for soil productivity, including carbon, of changing crop production strategies. Subobjective 2A: Conduct evaluations of short-term carbon mineralization and water extractable organic C and N as a predictor of potential nitrogen mineralization in soil under conventional (inorganic) and organic fertilization.
To determine runoff water quality impacts of fertilizer recommendations based on enhanced soil testing methods, water quality samples from 6 field-scale cultivated watersheds at the Riesel Watersheds will be collected and analyzed. To evaluate the impacts of liquid fertilizer injection guided by GPS auto-steer technology on crop yield and economics, four replicated treatments (0, 20, 30, and 40 gal rates of 24-8-0 liquid fertilizer) will be implemented on two 25-ac fields, and crop yield, cost, and revenue data will be collected and analyzed. To evaluate short-term carbon mineralization and water extractable organic C and N as a predictor of potential nitrogen mineralization, soil samples will be collected from across the country and include samples from the NAPT soil database. Each sample will be analyzed using the ARS-developed Solvita respiration method and other currently used mineralization tests.