Linking Soil Properties to Mangrove Structural Parameters Across a Disturbance Gradient in the Northern Veracruz,...

Mangrove composition and structure vary with soil properties and alterations in these conditions may result in forest degradation. This study examines how soil properties relate to mangrove structure across three disturbance states. The study was conducted within the Ramsar Site 1602 in Veracruz, Mexico. Soil properties (organic matter, organic carbon, total nitrogen, salinity, pH, and conductivity) and structural parameters (density, basal area, height, and diameter at breast height) were measured in 100 m² plots along four transects perpendicular to the coast. Plots represent apparently undisturbed (AU), semi-disturbed (SD), and disturbed (D) states. Differences in soil properties and structural parameters between forest states were first assessed using principal component analysis and PERMANOVA. Then, the relationship between forest structure and soil properties was investigated using redundancy analysis (RDA). Differences in soil and forest structural characteristics were significant between all disturbance states. AU plots had higher tree density, basal area, height, and richness and complexity index than SD plots, while no living trees were found in D. The RDA showed that silt content and soil pH were the main environmental factors significantly associated with variation in mangrove structure. Distance from the lagoon edge towards the coastline had a marginal effect and the overlap of SD and D plots indicated that the spread of forest decline was associated with changes in soil properties. Effective mangrove conservation requires soil restoration measures to prevent further degradation.