Annual litterfall in an Atlantic Forest fragment in Northeast Brazil

Abstract

The ecological structure of forest fragments is closely related to the dynamics of biological flows directly dependent on the decomposition of the litterfall, which is the main mechanism of recycling nutrients to plants. In this sense, the objective of the present work was to quantify the annual litterfall productionduring the period from April 2013 to March 2014 in Mata do Bebo, an Atlantic Forest fragment located in Macaíba, Rio Grande do Norte. 10 conical collectors were used to obtain the data on the litter contribution, with an average opening area of 0.128 m², placed 1 m above the ground.. The material was collected monthly, dried at air temperature for 48 h, and separated into four fractions: leaves, bark and branches, reproductive material; and miscellaneous material. After separation, the fractions were weighed and stored. The total contribution of litter was uninterrupted and totaled 5,038.72 kg ha -1 year -1 , with the highest production in September, at the beginning of the dry season, and the lowest in July. The foliar fraction made the largest contribution, with 3,744.26 kg ha -1 year -1 , followed by the reproductive material, which reached 846.29 kg ha -1 year -1 , branches and bark, with 396.10 kg ha -1 year -1 , and miscellaneous material, with 52,069 kg ha -1 year -1 . The correlations of litterfall production with rainfall and temperature were negative. The litterfall production in the fragment was lower than that obtained in other remaining Atlantic Forest areas, possibly because it is located in a region considered an ecotone between the Caatinga and Atlantic Forest biomes, besides the anthropic effect to which it has been submitted for decades.