SOUZA, B. V.; http://lattes.cnpq.br/4028993566761734; SOUZA, Bruna Vieira de.
Résumé:
Forests play a significant role in storing large amounts of Carbon in their biomass and other
forest compartments, as in the understory, litter and soil. Thus, this study aimed to determine
the amount of organic Carbon in an area of Caatinga different successional stages, in the
compartments: understory, litter and soil in the rainy season and drought. The study was
carried out at Cachoeira de São Porfírio, the city of Varzea – PB in 4 (four) areas de 3000
square meters each, with vegetation in different successional stages. Samples were collected
from plant material in understory and litter, and soil samples to determine the levels of
Carbon. The collect of understory and litter totaled 120 samples in each compartment. The
plant material was sent to the laboratory of EMBRAPA Semi-Arido Petrolina-PE, to
determine the organic carbon content. The soil was collected at 04 depths (0-5 cm, 5-10 cm,
10-15 cm and 15-20 cm), totaling 96 samples in the rainy season and dry season. Analyzes
soil were performed at the Laboratory of Soil and Water / UFCG in Patos (PB). For
comparison of the carbon content in each behavior was used, the significance level of 5%, and
statistical analyzes carried out using the ASSISTAT statistical program. Were recorded in the
rainy season, the highest values of carbon in the understory of Initial Secondary Caatinga,
with 0.74 kg ha-1. In the dry season the highest carbon content was found in the Secondary
Late Caatinga (0.68 kg ha-1). Litter in Caatinga Preserved had the highest average content of
carbon and 2.42 kg ha-1 in the rainy season, in dry season, the area of Caatinga Late
Secondary showed the highest carbon content (2.39 kg ha-1) and lowest value was obtained in
the area of Caatinga Initial Secondary with 2.08 kg ha-1 carbon. The carbon content in the soil
showed significant differences for time factors, the study area and depth. In the rainy season
in the area of Caatinga Secondary Late was recorded the highest content of carbon in the soil
with 9.00 Mg ha-1. In the dry season, the highest average content of carbon is in the area of
Caatinga Preserved with 14.99 Mg ha-1. The Caatinga Late Secondary in the rainy season had
the largest stock of carbon (33.01 Mg ha-1). In the dry season, the highest carbon stock was in
the area of Caatinga Preserved with 49.77 Mg ha-1 carbon. The results of this study
determined that the highest organic carbon contents were found in the area of Caatinga
Preserved, and higher carbon concentrations were recorded during the dry season. Among the
vegetable compartments, the highest concentration of carbon occurs in the litter. In soil, the
highest concentration of carbon occurred in the surface layer (0-5 cm).