Project Details:

Amount and timing of nitrogen release from poultry litter in soybean production system

Parent Project: This is the first year of this project.
Checkoff Organization:Alabama Soybean Producers
Categories:Soil fertility
Organization Project Code:
Project Year:2019
Lead Principal Investigator:Rishi Prasad (Auburn University)
Co-Principal Investigators:
Tim Reed (Auburn University)

Contributing Organizations

Funding Institutions

Information and Results

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Project Summary

Poultry litter is a rich source of plant nutrients. However much of the included nitrogen (N) is in an organic form that becomes available to crops via the microbial mediated process of mineralization. The mineralization process is strongly influenced by the composition of the litter, environmental factors such as soil temperature and water content, and the soil characteristics. Most growers typically use 60-60-40 (lb./ton) as the total nutrients (N-P2O5-K2O) and 40-40-30 (lb./ton) as the available nutrients during first season of litter application. However, growers are poorly informed as to when these nutrients, especially N, is available to plants. Growers who apply litter must understand that it is essential to supply adequate amounts of plant available N during periods of substantial plant N demand. Poor synchronization between plant N demand and soil N supply often leads to plant stress, yield loss, and increases the risk of N loss to the environment via denitrification, leaching or volatilization pathways. To obtain maximum N value from litter, minimize losses of nitrogen to the environment, and informed on application timing and amount of sidedress N, it is important to know how much and when N becomes available to crops from litter application each year.

Project Objectives

Most studies have evaluated the mineralization potential of litter under laboratory conditions, which do not reflect the actual field conditions. Here, we propose a field (in-situ) study to understand the mineralization behavior of litter applied at common rates typically found in dryland conditions. Thus, the objective of the study is to quantify and compare the amount and timing of nitrogen release from mineralization of litter applied at three rates (3, 2 and 1 tons/acre) over the soybean growing season in dryland condition. The data will be used to model N release under diverse soil and environmental conditions and obtain estimates of sidedress N and application timing.

Project Deliverables

Fields plots at E.V Smith Research center and Wiregrass Research and Extension center will be established in a field with a history of soybean production to which litter has not been applied. Litter bags will be prepared using screen mesh and filled with poultry litter according to the treatment rates. The treatments will be a control (no litter) and three rates of litter (5, 2.5 and 1.0 tons/acre) replicated four times in a field under dryland condition. The litter bags will be removed at 1, 3, 5 10, 20, 30, 40, 50, 60, 70, 80, 90, 120 days after litter application. The bags will be transported to the lab and analyzed for total nitrogen and total carbon using standard methods. The net N mineralized over time will be calculated for each treatment by subtracting the control from treatments.Soil temperature and soil moisture content at 15 cm depth from designated cylinders will also be monitored using Stevens Hydra Probes.

Progress of Work

Final Project Results

Benefit to Soybean Farmers

Performance Metrics

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