Considering the importance of nutrient cycling as an indicator in the maintenance of
the productivity of the ecosystem, the present study aimed to assess the seasonal
dynamics of production and decomposition rate of litter in a fragment of Cerrado sensu
stricto. For evaluation of supply of burlap were used 50 circular collectors with 112.8
cm diameter, distributed systematically. Litter collections were performed monthly June
2016-may 2017 and the collected material was packed in plastic bags, then taken to
the laboratory where the separation was carried out in fractions leaves, twigs and
reproductive material. After that, the material was packed in paper bags and washed
the greenhouse at the 70 C, for the determination of the dry weight. The decomposition
of leaf litter was evaluated using the method of litter bags, with random distribution of
288 litter bags containing 20 grams of leaves and 24 litter bags containing 20 grams
of branches. The annual production of litterfall was quantified in 6.042,50 kg. ha-1. yr-
1, in which the leaf was prevalent fraction presented a production of 4.644,40 kg. ha-1.
yr-1, then the fractions branches (1.084,10 kg. ha-1. yr-1) and reproductive material
(329,90 kg. ha-1. yr-1). The litterfall obtained higher production in July with 1.464,00 kg.
ha-1 and lower production in the month of December (138,70 kg. ha-1). A significant
negative correlation was observed between litterfall and its fractions with the
precipitation and relative humidity. The decomposition of foliar mass reached 49% and
50% of twigs during the nine-month period, in which the decomposition constant (k) for
leaf mass and for branches was 0.0030 g g-1-1day.For this constant, the estimate for
the disappearance of total mass has been estimated to be 1.000 days (29 months). It
can be concluded that the litterfall presented seasonality well marked, with higher
output during the dry season and lower in the rainy season with strong influence of
precipitation and relative humidity in the deposition of the leaves. The breakdown
proved slow for both leaves as for branches to get the value of the constant of
decomposition 0.0030 g g-1-1 day for both.
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