Location: Plant Science Research
Project Number: 6070-21600-001-014-R
Project Type: Reimbursable Cooperative Agreement
Start Date: Jan 1, 2025
End Date: Dec 31, 2025
Objective:
1. Quantify actual stocks of SOC on private farms in the southeastern US 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 SOC stock, soil health condition, historical cotton production estimates, 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:
Cotton growers throughout the southeastern US 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 NRCS 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. 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 crop rotation sequences with peanut and cotton as a key component 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). Over the course of four years of this project, at least 12 “ecoregion nodes” will be sampled.
Projected sampling of ecoregion nodes might follow the following schedule:
2025 High Plains of TX; Central Rolling Plains of TX; Blackland Prairie of TX; Gulf Coast Prairie of TX; Rio Grande Valley of TX
Surface residue and soil will be sampled following a standardized approach according to the following. Two representative locations within a field of interest will be located and up to five sampling points around each location will be sampled and composited to obtain two replicate samples per field. The intent will be to maximize the number of fields with unique management style, duration, and geographic location rather than obtain numerous subsamples within a field. Surface residue within a 30-cm diameter ring will be collected at each replicate to characterize ground cover and to analyze for C and N 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 C and N concentrations. Soil N levels, including NO3- and NH4+, will be analyzed at all soil depths collected. Soil will be dried, sieved, and analyzed for total, particulate, and mineralizable C and N 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, as described in Franzluebbers (2021).
