Physical, chemical and biological characterization of applied organic amendments in crop production in Dominican Republic

The benefits of the application of organic fertilization in agriculture are worldly know, however, there are few studies regarding nutritional content and biological activities of these organic fertilizers. In Dominican Republic, these amendments have been applied to crops over two decades; however, its physical and biological properties remain no investigated. The aim of this research was to study the physical, chemical and biological features of organic amendments more used in Dominican Republic, including the characterization of organic sources to compose the organic amendments. Forty three samples of organic amendments were obtained and analyzed from locations of Jarabacoa, Espaillat, La Vega and Montecristi during the period of January 2005 to July 2006. The results showed that bokashi plants Jarabacoa "BPJ" type presented higher organic matter (MO) content with 44%, P (6.1%), K (3.6%), Ca (21.7%) and micro nutrients (Mn, Zn) than other bokashi evaluated. The highest value of OM content (52%) was observed in Justino Peguero type "CJP" within compost materials, but with nutrients contents same to the other compost. The MO content values were superior in earthworm humus (76% in average) then bokashi (33%) and compost (34%). The results demonstrated that the physical, chemical and biological characteristics of the organic amendments evaluated vary with management conditions, type of material used in its preparation, environmental conditions and elaboration processes.