Estimate of coffee huck mineralization, by the method of litterbag, as function of N fertilizer levels

Abstract

There is evidence that coffee husk mineralization, when used as organic fertilizer, is slower than would be expected because of the high C: N ratio. So, the N application may improves this process. The present study proposes to estimate the coffee husk mineralization by the litter-bag method and N and S release in field conditions, as affected by nitrogen levels. The experiment will be conducted over a period of five months, in São Manuel (SP), where litter bags will be arranged on the soil surface under the coffee plants canopy. Will be performed five litter bags assays with coffee husk. It will be applied the equivalent of 0, 80, 160, 240, and 320 kg ha-1 N in urea form, in the presence and absence of 10 ton ha-1 of coffee husk from coffee dry coconut processing. The litter bags will be placed on the ground where the treatments will be applied. There will be five sample times, at 30, 60, 90, 120, and 150th days after the beginning of the experiment. Each sampling time it will be collected one litter bag of each treatment. There will be a characterization of the coffee husk used in the experiment before application and after the end of it. It will be assayed N, P, K, S, Ca, Mg, and total C in dry matter. In addition, it will be determined the husk mass in litter bags in each sample.(AU)