Swine Effluent Irrigation Rate and Timing Effects on Bermudagrass Growth, Nitrogen and Phosphorus Utilization, and Residual Soil Nitrogen

• Published in: Journal of environmental quality 2003-03, Vol.32 (2), p.681-686
• Main Authors: Adeli, A, Varco, J.J, Rowe, D.E
• Format: Article
• Language: English
• Subjects: Agricultural and forest climatology and meteorology. Irrigation. Drainage; Agriculture; Agronomy. Soil science and plant productions; Animals; Biological and medical sciences; Climatic conditions; Cynodon - growth & development; Dry matter; Effluents; Fundamental and applied biological sciences. Psychology; General agronomy. Plant production; Impaired water use; Irrigation. Drainage; Lagoons; Manure; Nitrogen; Nitrogen - analysis; Nitrogen - metabolism; Nutrient availability; Other nutrients. Amendments. Solid and liquid wastes. Sludges and slurries; Phosphorus - analysis; Phosphorus - metabolism; Residual soils; Seasons; Soil Pollutants - analysis; Soil Pollutants - metabolism; Soil profiles; Soil-plant relationships. Soil fertility. Fertilization. Amendments; Summer; Swine; Waste Disposal, Fluid; Wastewater irrigation; Water Supply
• ISSN: 0047-2425; 1537-2537; 1537-2537
• DOI: 10.2134/jeq2003.0681

Maximizing utilization of effluent nutrients by forage grasses requires a better understanding of irrigation rate and timing effects. This study was conducted in 1998 and 1999 on a Vaiden silty clay (very-fine, smectitic, thermic Aquic Dystrudert) soil to determine the effects of swine lagoon effluent irrigation rate and timing on bermudagrass [Cynodon dactylon (L.) Pers.] growth, nitrogen (N) and phosphorus (P) recovery, and postseason soil profile NO3− –N. Treatments consisted of swine effluent irrigation at the rates of 0, 5, 10, 15, and 20 ha-cm. Two additional treatments included 2.5 ha-cm applied on 1 September and 1 October in addition to a base summer rate of 10 ha-cm. In both years for early to mid-season irrigation, bermudagrass dry matter yield quadratically increased with increasing swine effluent irrigation rates. Averaged across years, effluent irrigation in October resulted in 30% less dry matter than in September. For late-season irrigation, apparent N recovery averaged 59% less and P recovery averaged 46% less with a delay in irrigation from 1 September to 1 October. The greatest quantity of soil NO3− –N was associated with both the greatest effluent rate and October irrigation treatments. Minimal yield benefit was obtained when effluent was applied at rates greater than 10 ha-cm during the summer months. Late-season irrigation, especially after 1 October for areas with similar climatic conditions, should be avoided to maximize synchronization of nutrient availability with maximum growth rates to minimize potential offsite movement of residual soil N and P.