Evaluating a Nonionic Surfactant as a Tool to Improve Water Availability in Irrigated Cotton

Authors: Sullivan, Dana; Nuti, Russell; Truman, Clinton

Submitted to: Hydrological Processes
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/24/2009
Publication Date: 7/1/2009
Citation: Sullivan, D.G., Nuti, R.C., Truman, C.C. 2009. Evaluating a Nonionic Surfactant as a Tool to Improve Water Availability in Irrigated Cotton. Hydrological Processes. 23:2326-2334.

Interpretive Summary: Nonionic surfactants have been well-researched in turf grass environments as a tool to ameliorate water repellant conditions. However, few studies have evaluated the risks and benefits of nonionic surfactant applications in row-crop agricultural systems. The objective of the current study was to determine if a nonionic surfactant could be used to conserve water in a southeastern Coastal Plain cotton (Gossypium hirsutum L.) production system. The study was comprised of two components: 1) on site rainfall simulation and 2) agronomic cotton field trials. Treatments were designed to test the impact of rate and frequency of surfactant applications using six combinations of application rates and timings. For the rainfall simulation component, only the control (0.0 L ha-1) and high rate (0.51 L ha-1) of surfactant applications were evaluated. Results from the rainfall simulation experiment showed that surfactant additions led to increased runoff, decreased infiltration and reduced sediment losses. However, under natural rainfall, agronomic field trials showed no differences in crop yields between surfactant treated and untreated plots. Data demonstrate the need for clarification of soil physical/chemical properties and surfactant interactions that may lend themselves to the creation of surface seals and how these seals impact soil/water conservation and crop yield.

Technical Abstract: Nonionic surfactants have been well-researched in turf grass environments as a tool to ameliorate water repellant conditions. However, few studies have evaluated the risks and benefits of nonionic surfactant applications in row-crop agricultural systems. The objective of this study was to evaluate the impact of a nonionic surfactant on cotton (Gossypium hirsutum L.) production on a Faceville series (fine, kaolinitic thermic Typic Kandiudult) in the Coastal Plain region of Georgia. The experiment was made up of two components: 1) on site rainfall simulation and 2) agronomic cotton field trials. Treatments were designed to test the impact of rate and frequency of surfactant applications using six combinations of application rates and timings. For the rainfall simulation component, only the control (0.0 L ha-1) and high rate (0.51 L ha-1) of surfactant applications were evaluated. During the field trial, soil water content, cotton stand counts and yield were measured. Rainfall simulations showed that the addition of surfactant increased runoff, decreased infiltration and reduced sediment losses. The surfactant likely caused soil particles to disperse during application (which was applied with 12.7 mm water), creating a surface seal. Despite the demonstrated potential for water loss, agronomic field trials showed that crop yields were not significantly different between surfactant treated and untreated plots. Data demonstrate the need for clarification of soil physical/chemical properties and surfactant interactions that may lend themselves to the creation of surface seals and how these seals impact soil/water conservation and crop yield.