This study evaluated the performance of the overall plant litter production and its components (leaves, branches and flowers / fruits), as well as the relationship between these variables both in natural conditions such as scarcity of rainfall in the order of 50%. The study was conducted in native forest land within the National Forest Caxiuanã, State of Pará. Productions were measured monthly average total accumulated plant litter and its components in two plots of 1 ha each, during the years of 2004-2010. We also measured the total monthly rainfall in the study area for the same period. The production of vegetable total accumulated litter was 5.52 and 4.43 t.ha-1.year-1, respectively for the control and treatment plots, a reduction of approximately 24,6% in the production of forest litter, when subjected to water stress induced. The accumulated production of leaves, twigs and flowers / fruits was 3.66, 0.77 and 0.65 t ha-1.year-1, 3.16, 0.62 and 0.37 t ha-1.year -1, respectively, for the control and treatment plots, a reduction of approximately 15.82%, 24.19% and 75%, among the productions of the components of accumulated litter the control plot in relation to treatment plot. The data of monthly precipitation totals showed great variability, standard deviation and coefficient of variation of 135.2 and 81.7%, respectively. The variable accumulated litter production and its components, showed annual seasonal pattern, with the highest and lowest values occurring between the months less (June to November) and wettest (December to May), respectively. The variable, total precipitation, presented annual seasonal behavior, with the highest and lowest values occurring between the months of December and May and between June and November, respectively. The trend line that best fit to the data of the variables studied was the model polynomial of 5th degree, however, with high grades and low grade adjustment, respectively, for the variable production of plant litter accumulated total (R ² ≥ 0, 86), and total monthly rainfall (R ² = 0.1702). The two variables were inversely with greater intensity for the component flowers / fruits. Apparently, the treatment reduced the degree of correlation between variables, precipitation and cumulative production of leaves and flowers / fruits and increased the degree of correlation for the component of the total accumulated litter, twigs.
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