Sewage sludge-based organomineral fertilizer improves phosphorus efficiency in Urochloa brizantha
Year: 2025
Type: article
Abstract: ABSTRACT Sewage sludge (SS) from wastewater treatment has reasonable phosphorus (P) levels, which could be used as fertilizer in agriculture. However, SS-P content is lower than mineral fertilizers, which limits its operational application. The blend of organic and mineral material can increase the P content, formulating organomineral fertilizers (OMF) with higher P levels, enabling agricultural use. This study aimed to assess the agronomic efficiency and residual effect of organomineral fertilizers derived from SS as phosphorus sources for Urochloa brizantha. A greenhouse pot experiment was conducted to evaluate the successive cultivation of U. brizantha over eight cycles, with the following treatments: SS organic compost (SSC) powder; SSC pelletized (SSP), SSC+MAP pelletized (S+MAP) and SSC+AshDec ® pelletized (S+ASD); AshDec ® powder (ASD), monoammonium phosphate (MAP) and a control (no P). In each Urochloa cycle, height, tillering, shoot dry mass (SDM), and leaf P were evaluated. After eight cycles, the soil was subjected to P fractional analysis. Our results showed that tillering was higher in all treatments with P compared to control (No P). Shoot dry mass production in the first cycle was higher with S+MAP (21.8 g pot -1 ) than MAP (17.5 g pot -1 ), and after eight cycles, the accumulated SDM of all treatments (>140 g pot -1 ) was superior to MAP (132 g pot -1 ), except for S+ASD (118 g pot -1 ). No significant difference in plant height was observed. Total P uptake was higher in the treatments with recycled sources, however, plants fertilized with S+MAP accumulated more P during establishment, while SSC, SSP, and ASD promoted higher accumulation during 4 to 6 cycles. After eight cycles, soil labile P content was higher in treatments with OMFs compared to mineral sources, indicating a residual effect of organomineral fertilization. These results showed that SSC-derived OMFs are more efficient than conventional fertilizers if mixed with soluble mineral sources (MAP), but the same is not true with insoluble sources (ASD). Organomineral S+MAP can replace MAP, providing greater efficiency in forage establishment and a greater residual effect.
Language: English
Subfield: Soil Science
Domain: Life Sciences
Open Access status: gold
Estimated APC paid: $100
OpenAlex ID: W4411333110