Author: Nelson Ray Benson

Publisher:

Published: 2023

Total Pages: 0

ISBN-13:

Temporal and spatial variations in crop performance are common in agricultural production fields in northeastern Arkansas. With the alluvial soils of the Mississippi Delta region, within-field soil texture can range from coarse sand to heavy clay. Such variability influences chemical and physical soil properties that affect yield potential of the region's commercial cropping systems. With advances in precision management, delineating large commercial fields into zones of homogenous production potential could increase profitability and improve efficiency. Standardized criteria for defining homogeneity within potential delineation zones have not been developed or field-tested in the region, which includes Mississippi County, Arkansas, the largest cotton (Gossypium hirsutum L.) production area in the US Midsouth. In this study, methods for creating management zones in spatially variable commercial fields were examined using multi-year yield monitor data from five commercial fields. Results showed that global and local Moran's I spatial analysis could identify areas of similarity of georeferenced yield monitor and apparent soil electrical conductivity (ECa) measurements. Zone delineation using cluster analysis of multi-year yield monitor data provided a more consistent delineation method than using soil ECa alone. The spatial analysis procedures outlined in this study provide guidelines for developing best management practices for delineating northeast Arkansas fields into zones representing homogeneous production potential. The study also included small plot and strip trials evaluating cotton response to crop inputs across spatially variable production fields. Results showed that cotton seeding density and irrigation timing could be adjusted to offset production inputs in low-yield potential delineation zones, thereby increasing net revenue. These data also were analyzed for sustainability scores using the Fieldprint® Calculator. With uniform application of inputs, cotton yield potential inherent to soil texture zones within the field was the most important factor contributing to improved natural resource sustainability. Weather patterns were such that irrigation did not improve cotton yield during the three years, and as a result, irrigation decreased the water use efficiency benchmark, thereby reducing the overall sustainability score. Future studies should be directed at measuring the sustainability impact of site-specific input applications based on sub-field production potential.