Comparative effects of food processing liquid slurry and inorganic fertilizers on tanner grass (Brachiaria arrecta) pasture: grass yield, crude protein and P levels and residual soil N and P
Citation
St. Luce, M., Gouveia, G.G., Eudoxie, G.D. (2017). Comparative effects of food processing liquid slurry and inorganic fertilizers on tanner grass (Brachiaria arrecta) pasture: grass yield, crude protein and P levels and residual soil N and P. Grass and Forage Science, [online] 72(3), 401-413. http://dx.doi.org/10.1111/gfs.12240
Plain language summary
Development of sustainable waste disposal practices is critical for the health of the environment and can serve as a means to recycle nutrients. This study evaluated food processing wastewater slurry from a as a potential fertilizer for tanner grass production on an acidic loam soil in the Caribbean. The food processing wastewater slurry did not improve the dry matter yield and quality of the tanner grass in comparison to commercial nitrogen and phosphorus fertilizers. However, in comparison to unfertilized plots, the food processing wastewater slurry applied at 200 kg N/ha significantly increased dry matter yield, crude protein and phosphorus content of the tanner grass. In conclusion, this study suggests that application of evaluated food processing wastewater slurry to pastures is a viable and sustainable alternative to landfill disposal.
Abstract
This small-plot field study evaluated food processing liquid slurry (FPLS) as a potential fertilizer for tanner grass (Brachiaria arrecta) production on an acidic loam soil. The treatments, arranged in a randomized complete block design with three replicates, consisted of an unfertilized control, inorganic fertilizer applied at 50 and 200 kg nitrogen (N) ha−1 with and without phosphorus (P) at 50 kg P ha−1, and FPLS applied at 50 and 200 kg N ha−1. Compared to the unfertilized control, the FPLS applied at 200 kg N ha−1 significantly increased grass dry-matter yield (DMY), herbage crude protein (CP) and P content, and N and P uptake in the second of two trials and P uptake in both trials. However, DMY and contents, of CP and P were generally lower for the FPLS treatments compared to the inorganic fertilizers. Apparent N recovery was higher for the inorganic fertilizer treatments than FPLS treatments in trial 1, while apparent P recovery was similar among all treatments in both trials. The FPLS treatments did not significantly increase soil NO3-N and P concentrations, but increased NH4-N in the 0–15 cm layer. The results suggest that application of FPLS to tanner grass pastures is an alternative to its disposal in landfill.