Dinâmica de serapilheira em áreas submetidas a diferentes métodos de restauração florestal, Paragominas, Pará, Brasil.

Abstract

The forest restoration process previously degraded by mining has grown steadily over the last two decades and monitoring of these environments is necessary. Litter is considered a good environmental indicator and should be used in the evaluation of forest restoration. The study was conducted at the company Mineração Paragominas SA, located in the municipality of Paragominas, from where bauxite is extracted since 2007, using mainly two methods for forest restoration, as follows: planting native seedlings (PM) and induction of natural regeneration (RN). In this sense, the tested hypothesis is that: the RN method is most effective as production, decomposition, water retention capacity and nutritional quality of litter in restoration areas because the initial dominance of pioneer species of rapid growth contribute to the increasing and improving these characteristics, when compared to the PM method of different species, approaching this way a fragment of native forest (FF), used in this work as a reference. With that aimed to contrast the contribution (a), stock and water retention capacity in the dry season and rainy (b), in addition to evaluating the contribution of macro and micronutrients in the PM ecosystems, RN and FF (c). Litter aportada was collected monthly from September 2014 to October 2015, was also held static trimensalmente collected with the aid of a template, for the purpose of calculation of decay, renewal and estimate the water retention capacity (CRH) litter. All material after collected was sorted in 5 fractions (leaves, twigs, reproductive material, thick branches and miscellaneous) in supply and three (leaves, branches and miscellaneous) in stock. The deposition, ecomposition rate, and CRH of accumulated litter was higher in the areas of FF and RN, with the highest average dry matter aportadas in the months with less rainfall and higher temperatures. The deposition of the fraction was the most representative sheets with 91.67, 79.66 and 82.81% in the areas NB, FF and PM respectively. CRH was higher in the rainy season, with highest average fraction of the sheets stored in the areas of RN and FF, however, there was total dry mass difference between ecosystems or between periods of evaluation. RN method was more efficient compared to the PM and can be expanded to new areas, especially where the topsoil characteristics show a good aptitude for this purpose.