Producción de hojarasca y su aporte de nutrientes en cacao bajo diferentes esquemas de fertilización, Rionegro-Santander

espanolEl sistema productivo cacaotero contribuye con la sustentabilidad del manejo de suelos a traves del reciclaje de nutrientes, junto con la produccion de hojarasca. Objetivo. Estimar el aporte de biomasa y nutrientes en plantaciones de cacao bajo efectos de fertilizacion quimica y organica. Materiales y metodos. En el SAF con cacao-CCN-51 (Theobroma cacao L.) asociado a matarraton (Gliricia sepium L.) en Rionegro (Santander), se evaluo el efecto de 4 fuentes de fertilizacion sobre la produccion de hojarasca (kg.ha-1 MS) y el aporte de nutrientes esenciales N, P, K, Ca, Mg (kg.ha-1). Se empleo un diseno de bloques completos al azar con 3 repeticiones, con los siguientes tratamientos: T1-Convencional, T2-Quimico, T3-Ecocacao y T4-Organico+quimico. La fertilizacion se realizo durante 3 anos. El aporte de hojarasca y nutrientes se evaluo durante el ultimo ano (2012), mediante trampas colectoras muestreadas mensualmente y analizadas en 2 epocas del ano: bajas precipitaciones (BP: enero-febrero) y altas precipitaciones (AP: julio-diciembre). El aporte de nutrientes se calculo mediante el contenido de N, P, K, Ca, Mg determinado en laboratorio a partir de la hojarasca recolectada. Resultados. Los mayores aportes de hojarasca se presentaron en epoca de altas precipitaciones para el T3-ecocacao y T2-quimico con 567,2 y 541,33 kg.ha-1 MS, respectivamente. La variacion estacional por epoca del ano tuvo efecto significativo sobre el aporte de P, K, Ca y Mg presente en hojarasca de cacao. Se observo que en el 80% de los casos el mayor aporte de nutrientes fue en epoca de BP. El T3-ecocacao se destaco por su aporte de los nutrientes N, Ca y Mg (8,11-7,74 y 1,02 kg.ha-1. ano-1, respectivamente). Conclusion. En Rionegro-Santander el mayor aporte de hojarasca lo realizo el T3-Ecocacao con 992,11 kg.ha-1.ano-1 MS que represento un valor monetario (como equivalente en fertilizante comercial) superior al 70% con respecto a T1-convencional. EnglishThe cocoa production system contributes to the sustainability of soil management, through the recycling of nutrients along with leaf litter production. Objective. To estimate the contribution of biomass and nutrients in cocoa plantations under the effects of chemical and organic fertilization. Materials and methods. In SAF with cocoa-CCN-51 (Theobroma cacao L.) associated to matarraton (Gliricia sepium L.) in Rionegro (Santander), it was evaluated the effect of 4 fertilization sources on the production of leaf litter (kg.ha-1 MS) and contribution of essential nutrients N, P, K, Ca, Mg (kg.ha-1). A complete randomized block design with 3 repetitions was used with these treatments: T1-Conventional, T2-Chemical, T3-Ecocacao and T4-Organic+Chemical. Fertilization was carried out during 3 years. The contribution of leaf litter and nutrients was evaluated the last year (2012), through collecting traps sampled monthly and analyzed in 2 times of the year: low rainfall (BP: January-February) and high rainfall (AP: July-December). The contribution of nutrients was calculated through the content of N, P, K, Ca, Mg determined in the laboratory with the leaf litter production per ha. Results. The highest contribution of leaf litter was occurred in the period of high rainfall for the treatments T3-Ecocacao and T2-Chemical with 567,2 and 541,33 kg.ha-1. MS, respectively. The seasonal variation by time of year had influenced signifivatively the contribution of N, P, K, Ca and Mg present in cocoa leaf litter. It was observed that in 80% of the cases a greater contribution of nutrients occurred in B.P season. The T3-ecocoa stood out for its contribution of N, Ca and Mg nutrients (8,11-7,74 and 1,02 kg.ha-1. year-1 respectively). Conclusion. In RionegroSantander, the greatest contribution of leaf litter was carried out by the T3-Ecocacao with 992.11 kg.ha-1.year-1 MS, that represented a 70% higher monetary value (in terms of commercial fertilizer cost) with respect to T1-conventional.