Influência da precipitação pluviométrica e umidade do solo no fluxo de liteira e estimativa de biomassa aérea na Floresta Nacional de Caxiuanã - PA.

Abstract

This study aimed to analyze the thin litter production and estimate the biomass gain in four distinct areas of forests as well as its correlation with rainfall and soil moisture in Caxiuanã National Forest, in the municipality of Melgaço - PA from January 2009 to December 2010. The fine collection of litter were collected biweekly by collectors. The fine litterfall showed a moderate level of correlation, negative correlation with rainfall and soil moisture, with the highest values of production in areas with more clayey soils, followed by the sandier areas. The leaves were the main component of litter fine for all areas of study, with approximately 77% of total production, followed by branches with 13%, with 5% fruit, flowers and 4% to 1% for miscellaneous. The estimated gain of biomass was performed by indirect methods, using two allometric equations, one for primary forest and secondary forest to another, analyzing their correlation with rainfall and soil moisture in Caxiuanã National Forest. The collections gain ground biomass occurred on a quarterly basis during the period studied. We also examined the basal area increment from December 2008 to October 2010 for each area. It was noted that there was a loss in the basal area significantly well in all areas, except the area excluding water. Noticed a very significant influence, especially in the area of exclusion of water, the effects of the global phenomenon of El Niño, the production of biomass and litter production. The biomass gain showed positive correlations with rainfall in all areas, but only one of the areas showed significant positive correlation with soil moisture.