Armazenamento de liteira e água em ecossistemas sucessionais do Baixo Rio Guamá, Amazônia Oriental.

Abstract

The litterfall is na importante indicator of the quality of ecosystems’ restoration, one in which the the physical properties of water storage and litter stock vary from oone ecosystem to another. In the Amazon, the Successional Forest Ecosystems of Interfluvial Highlands (SFEIHs) and the Successional Forest Ecosystems of Fluvial Plains (SFEFPs) are examples that represent differences for the litter factor. Therefore, the following question was proposed: Do the successional forest ecosystems of interfluvial highland possess a higher litter stock and water storage capacity when compared to the fluvial plain one? With the hypothesis that (h): if the highland interfluvial ecosystem presents a higher litter stock, so it will possess a higher water storage capacity, notwithstanding the time period in which it was collected. The experiment was carried out at the Federal Rural University of the Amazon (UFRA), at the campus located in Belém. Each ecosystem was considered as a form of treatment and had 12 tracts of 10x10m implanted; using a metallic collector, 36 samples were collected in each ecosystem, with a lapse of 6 months between each sample. For this study, we performed a floristic survey (CBH>15cm) of the ecosystems and collected litterfall samples to determine its storage on the ground surface (Mg.ha-1) and the water storage percentage (%). The outline we applied to the experiment was entirely randomized with a 2x2 distribution. The Euterpe oleraceae presented the most expressive values across both ecosystems and the Fabaceae family was the richest one as far as the number of species is concerned. After analyzing the average values collected regarding the physical properties of the litterfall, its litter stock and water storage capacity, we rejected the hypothesis (ANOVA, p < 0,05). The SFEIHs ecosystem presented the higher litter stock in the time period when there was less rain (10,5 ± Mg.ha1) and the SFEFPs ecosystem presented the higher water storage average during the rainy season 349%). Thus, we concluded that the ecosystem with the higher litter stock value does not present the higher water storage capacity, which leads us to believe that these characteristics derive from factors pertaining to the system itself.