A preliminary study on the potential for cycling solids from geotube treatment of dairy lagoon wastewater.

摘要

GeotubeReg. residual solids (GRS) are a potential bioresource that could be used to improve soil physical and chemical properties on agricultural land. Yet, chemical properties of GRS could affect plant growth and repeated land application of GRS could elevate soil nutrient content and contribute transport and loss of nutrients in drainage water. The first objective was to evaluate the effects of increasing rates of GRS on physical, chemical and biological properties of contrasting soil types during turfgrass establishment. The second objective was to evaluate leaching losses of nutrients from contrasting soil types with and without incorporation of GRS during turfgrass establishment. Incorporation of GRS enhanced turfgrass growth and physical and chemical properties of contrasting soil types. However, following application of GRS, soil concentration of NO₃-N exceeded turfgrass uptake and excessive leaching loss of NO₃-N occurred. At high soil pH, residual Alum and associated hydrolysis products in GRS did not increase extractable soil Al, but did minimize leachate concentrations of dissolved reactive P forms. Composition, timing and application rate of GRS should be managed to optimize turfgrass establishment and prevent leaching loss of dissolved nutrients.