ABSTRACT
Nitrogen and phosphorus availability from a salmon hydrolyzed fertilizer: A study in controlled conditions

Juan Hirzel1* and Luis Inostroza1
 
The global tendency of higher production of fish has naturally led to more available derivatives of this industry such as hydrolysates, whose elevated percentage of proteins and mineral nutrients allows them to be used as a fertilization complement in agriculture. One of these products is salmon hydrolysate fertilizer, with unknown fertilizing value. This study determined the dynamics and delivery rate of N and P from a salmon hydrolysate fertilizer produced in Chile. Under controlled laboratory conditions using volcanic soil, a conventional fertilization treatment (urea and triple superphosphate) and control without fertilization were applied. The soil was incubated at 25 °C and 80% of usable humidity at times of 0, 7, 14, 21, 56 and 112 d. The results indicated that the salmon hydrolyzed fertilizer presented a rapid and high N delivery rate (104.2% availability), and its net N delivery value was higher than that obtained with urea. The P applied with salmon hydrolysate presented a high net delivery rate (68.4% availability) compared to triple superphosphate (6.6% availability) but showed erratic delivery dynamics. Soil pH and electrical conductivity were not affected. These results allow us to promote the idea that the use of salmon hydrolyzed fertilizer constitutes a good alternative to the use of conventional fertilizers.
Keywords: Salmon hydrolysates, soil fertility, nitrogen, phosphorus, soil incubation.
1Instituto de Investigaciones Agropecuarias, INIA Quilamapu, Chill?n, Chile.
*Corresponding author (jhirzel@inia.cl).