TITLE:
Population Dynamics of Croton blanchetianus Baill. in a Caatinga Area in the Brazilian Semi-Arid
AUTHORS:
Alecksandra Vieira de Lacerda, João Paulo Pereira de Lima, Tarcízio Jacinto de Oliveira Nunes, Azenate Campos Gomes, Carina Seixas Maia Dornelas, Hugo Morais de Alcântara, Francisca Maria Barbosa
KEYWORDS:
Marmeleiro, Populational Structure, Ecosystemic Dynamic, Seasonality, Dry Forests
JOURNAL NAME:
American Journal of Plant Sciences,
Vol.9 No.4,
March
30,
2018
ABSTRACT: The vegetation of the Caatinga, present in the dry
areas of the Brazilian Semi-arid region has been little studied, when it
relates to population dynamics of their species. The objective of this study
was to evaluate the mortality and recruitment rates of a Croton blanchetianus Baill. population in a two-year interval (January/2013
to January/2015), in area of caatinga in the semi-arid Paraiba. Monitoring of
structural changes in the vegetation was carried out in 96 10 × 10 m contiguous plots. The phytosociological
survey conducted in January 2013 sampled 1078 individuals of C. blanchetianus, occurring in the 96
plots studied. The years of 2012 and 2013 had rainfall below the annual
average. Take into consideration the evaluation period; there was a high
mortality rate (M = 47.33% year-1) and a low recruitment rate (R = 0.18% year-1) for the population of C. blanchetianus. The real gain (RG) of the population was
significantly negative (-93.91% year-1) since the number of dead individuals was much
higher than the recruited ones in the population. The highest height class,
composed of individuals of 4.1 to 5.0 m height, was the most tolerant to water
scarcity, resulting in 53.85% of surviving individuals. Therefore, the results
demonstrated that periodic droughts compromise the recruitment, development,
survival, and establishment of individuals in natural systems in the Brazilian
semi-arid region.