The structural heterogeneity of an urbanised mangrove forest area in southeastern Brazil: Influence of environmental factors and anthropogenic stressors

Abstract The objective of this study is to evaluate the characteristics of the forest in an urbanised mangrove using vegetation structure and abiotic conditions to distinguish habitat heterogeneity/quality. A total of 16 points in Vitória Bay were selected in the fringe and basin forests. The variables evaluated were height and diameter of the individual trees, basal area, density, dominance, interstitial water, litter mass, grain size, organic matter and anthropogenic influences. The results indicated that the mangrove area, due to suffering intensely from various anthropogenic effects, forests with varying degrees of maturity. Areas more distant from direct human effects had a higher degree of development and environmental quality relative to points closer to urban pressures. Intermediate development levels were also observed, which indicated pulses of environmental change. Human interventions caused alterations in the development of the forest which increased the mortality rate and reduced the diameter and height of the trees. The environmental variables of salinity, organic matter, litter mass, grain size and anthropogenic stressors contributed to the structural patterns. Our data suggest that an analysis of the vegetation structure and the abiotic factors are useful indicators to evaluate habitat quality, thus providing a basis for future management.