Sucessão ecológica em uma área de manguezal em processo de restauração no estuário do Rio Pacoti, Ceará

Abstract

Ecological succession in mangrove ecosystems involves structural and functional changes in vegetation over time, resulting from the interaction between initial conditions, environmental factors, and biological processes, and represents a key component in the assessment of ecological restoration areas. This study analyzed ecological succession in a restored mangrove area located in the Environmental Protection Area of the Pacoti River Estuary, Ceará, Brazil, based on population dynamics and growth patterns of Avicennia germinans over a temporal series. The study was conducted in three areas with different initial vegetation colonization conditions, associated with the previous presence of pioneer halophytic species (Batis maritima – Area 1 and Sesuvium portulacastrum – Area 2) and an adjacent control area (Area 3). Permanent plots were established to monitor the density and growth of A. germinans individuals, as well as to assess environmental variables, including sediment surface salinity and temperature. Throughout the monitoring period, population densities showed a similar pattern among the evaluated areas, with the highest mean values recorded in Area 2 (17.2 ± 12.9 ind/m2), followed by Area 1 (13.1 ± 11.7 ind/m2), while Area 3 exhibited the lowest densities (7.8 ± 7.7 ind/m2). Mean growth rates were higher in Area 1 (2.3 ± 6.7 cm/month), followed by Area 3 (2.1 ± 7.3 cm/month) and Area 2 (1.6 ± 5.0 cm/month). Surface salinity exhibited wide variation throughout the study period, ranging from 0‰ to 100‰, with similar mean values among the areas, while surface temperature values were also comparable, with slightly higher means in Area 1 (33.24 ± 2.65 °C). The results indicate that ecological succession in the restored areas tends toward structural convergence among sites with different initial colonization conditions. Over time, initial differences in density and growth of Avicennia germinans became progressively less pronounced, reflecting population reorganization associated with density-dependent processes and environmental variability, suggesting similar successional trajectories among the evaluated areas.