Comparative analysis of mangrove seedlings in natural, degraded, and restored ecosystems of Guyana

Abstract

ABSTRACT Mangrove seedlings are exposed to several environmental stress factors, which frequently affect the current state of their ecosystems. We examined the density, diversity, distribution, survival rates, and biophysical parameters of over 900 naturally existing seedlings in natural, degraded, and restored coastline ecosystems in Guyana. Systematic sampling was conducted for 1 year following the point-centred quarter method (PCQM) during the wet and dry seasons. The restored ecosystems had greater seedling densities (1546.44–5506.303 individuals/ha), diversity (0.65–0.65), and richness (0.46–0.51) when compared to the natural and degraded ecosystems. Seedling survival rates [41.9–53.4%] were greater in the natural ecosystems, but short-term seasonal variations were prevalent in the restored ecosystems. Significant disparities were observed in seeding biophysical parameters [df = 8, p < 2.2e-16] which also exhibited positive correlations [p < 0.05, rs < 0.75] with their respective locations. The restored ecosystems showed taller seedlings (137.54 ± 4.68 cm) with a greater number of leaves (30.87 ± 1.51–107.30 ± 5.54), while the natural ecosystems showed seedlings with greater stem diameters (3.05 ± 0.11–11.38 ± 0.37 mm). Our findings show that mangrove seedlings can exhibit site-specific differences which may be influenced by ecosystem type and seasonality to some extent.