Year-Round Soil Nutrient Dynamics from Broiler Litter Application to Three Bermudagrass Cultivars

Abstract

Understanding manure nutrient dynamics in soil with any crop is an important management practice for farmers and producers to document accountability and to use manure resources optimally. A field experiment was conducted to quantify input, output, and the year-round major plant nutrient dynamics in a fine sandy loam soil supplied with 15.75 Mg ha−1 yr−1 broiler litter. Soil samples were collected from pre-established plots of common bermudagrass [Cynodon dactylon (L.) Pers.] and hybrid bermudagrass cultivars Coastal and Tifton 85 for nutrient analysis. Coastal and Tifton 85 produced significantly greater annual dry matter yield (16948 and 18772 kg ha−1) than common bermudagrass (11238 kg ha−1). Tifton 85 was most efficient and removed 344, 58, and 472 kg ha−1 N, P, and K, respectively. The removal efficiency of these nutrients for Tifton 85 was 73, 18, and 114%, respectively. Soil pH varied from 6.0 to 6.6 until it decreased unexpectedly to 5.6 by the end of 2001. Total soil C increased from 11.4 g kg−1 to 17.9 g kg−1 by the end of the second year. At all sampling dates, the NO3–N concentration was greater than NH4–N while total N decreased during the maximum uptake in late spring and summer. Both total P and Mehlich-3 extractable P concentrations increased mainly in the 5- to 10-cm depth, indicating slight leaching of P. Results indicated that top yield from hybrid bermudagrass cultivars is possible with broiler litter as a sole fertilizer source. However, considerable nutrient imbalances in soil may occur in the long term if improper litter rates are used.