Decomposition of leaf litter in three forest ecosystems in Southwest Bahia State, Brazil

Abstract

The decomposition process influences the functioning of forest ecosystems, because it regulates the accumulation of soil organic matter and nutrient cycling. The objective of this study was to evaluate the decomposition of leaf litter in a native forest fragment (semideciduous forest) and two forest plantations (native species planting: Tabebuia impetiginosa, Tabebuia serratifolia, Tabebuia roseo-alba, Alchornea triplinervia and Astronium urundeuva and jackfruit planting. The decomposition was evaluated from the use of nylon bags containing about 10 grams of leaf material. The bags were collected at 30, 60, 90, 120, 150 and 180 days after installation. Were estimated the percentage of the remaining mass, the rate of decomposition (k) and half-life time of the litter (t1/2). At the end of the experiment, in the jackfruit planting, over 50% of the leaf material was decomposed, while in the native forest and in the native planting native the decomposition occurred of 34 and 35%, respectively. The coefficient k was higher for jackfruit planting (0,0033 g g-1 day), followed by native forest (0,0023 g g-1 day) and the native planting (0,0019 g g-1 day). The half-life time was 210,04 days (jackfruit planting), 364,81 days (native planting) and 301,37 days (native forest). The leaf litter of jackfruit planting has more rapid decomposition in relation to native forest and native planting. The decomposition process is influenced not only by the quality of the litter, but also by quality of the microenvironment of a given forest stand.