Location: Plant Science Research
Project Number: 6070-21600-001-006-R
Project Type: Reimbursable Cooperative Agreement
Start Date: Oct 1, 2022
End Date: Mar 1, 2027
Objective:
1. Quantify actual stocks of soil organic carbon on private farms in the southeastern United States that have been or are in early transition towards more conservation-based agricultural production based on the principles of soil health management.
2. Develop statistical associations among soil organic carbon stock, soil health, crop production, use efficiency of fertilizer inputs, and outputs of sustainability predicted from the Fieldprint Calculator of the Field to Market, as affected by management choices.
3. Characterize the suite of management practices that have the most potential for conserving natural resources while optimizing agricultural productivity output. Benefits of these analyses are expected (a) on the farm with improvement in soil health condition and potential for ecosystem market development and (b) to the public through social and environmental co-benefits.
Approach:
Crop producers (primarily with cotton and peanut as part of the rotation) throughout the southeastern United States will be contacted for collaboration. The intent will be to identify those growers having adopted conservation management using well-established soil health principles. Identification will be through contact of principal investigators with other investigators, university extension specialists, and USDA-Natural Resource Conservation Service agents throughout the region. Once identified, one to several fields on that farm will be sampled and the associated management history will be recorded with an interview with the farmer. A paired approach to obtain at least one sample from a neighboring farm in the locality with similar soil type will be part of the process. Within a particular “ecoregion node” (i.e., cluster of one to several neighboring counties with similar characteristics), our intent will be to sample a number of farms having different lengths of time of conservation management adoption, different dominant crop rotation sequences with peanut and cotton as part of the rotation, and as part of the paired approach to have different land cover types (e.g., disk-till cropland, no-till cropland, managed pasture, and hardwood and pine woodlands). On a yearly basis, the intent will be to sample approximately 24 fields within each of at least six “ecoregion nodes” in the region. Over the course of four years of this project, at least 24 “ecoregion nodes” will be sampled. Sampling within an “ecoregion node” may continue over the course of several years as needed to obtain a large enough range of field characteristics to make strong inferences about the effect of management on soil organic carbon stock change.
Surface residue and soil will be sampled following a standardized approach according to the following. A representative location within a field of interest will be located and up to five sampling points around this location will be sampled and composited to obtain one sample per field. The intent will be to maximize the number of fields with unique management style, duration, and geographic location rather than subsample within a field. Surface residue within a 30-cm diameter ring will be collected at one location to characterize ground cover and to analyze for carbon and nitrogen contents. Soil will be collected at depth of 0-10 cm using a 4-cm diameter coring device from five individual locations separated by a distance of 10 m in cardinal directions from a central point. Soil at depths of 10-30 cm and 30-60 cm will be collected at the same locations using a 3-cm diameter drill auger. Surface residue will be dried, ground, and analyzed for total carbon and nitrogen concentrations. Soil will be dried, sieved, and analyzed for total, particulate, and mineralizable carbon and nitrogen fractions according to standard operating protocols of the Soil Ecology and Management Lab at NC State University, and routine soil chemical analyses according to the North Carolina Department of Agriculture Soil Testing Laboratory.
