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Resumen (Introducción): La heterogeneidad ambiental de los manglares está consistentemente relacionada con factores biofísicos y antrópicos locales. Debido a que estos ecosistemas están sometidos a distintas presiones naturales o antrópicas, es necesario comprender el efecto de estas prácticas de manejo sobre sus componentes, para guiar acciones conducentes a incrementar su grado de resiliencia ante fenómenos meteorológicos extremos. (Objetivo): La propuesta de esta investigación consistió en evaluar la condición ambiental de 4 comunidades de manglar a partir del estudio de los componentes suelo y vegetación, mediante un conjunto de propiedades edáficas y dasométricas, en la zona norte de la laguna de Coyuca, México. (Metodología): La selección de los sitios de estudio y muestreo consideró su representatividad espacial, grado de alteración y proximidad a la línea de costa. Se caracterizó la estructura y biomasa arbórea y se tomaron muestras de suelo a una profundidad de 30 cm para su análisis en laboratorio. (Resultados): El inventario forestal mostró la presencia de las especies Rhizophora mangle, Laguncularia racemosa y Conocarpus erectus, cuya distribución está relacionada, principalmente, con el régimen hídrico del suelo, pH y salinidad. El almacén de carbono aéreo y edáfico fluctuó entre 41.5 y 165 Mg ha-1, siendo consistente con su grado de perturbación. (Conclusiones): Los principales efectos de las actividades antrópicas fueron la pérdida parcial de la estructura del bosque por tala y quema, compactación de la capa superficial del suelo, lo que deriva en el incremento de la densidad aparente y reducción del carbono almacenado en biomasa y suelo. Abstract (Introduction) The environmental heterogeneity of mangroves is consistently related to local biophysical and anthropic factors. Because these ecosystems are subject to different natural or anthropic pressures, understanding the effect of these management practices on their components is necessary to take action to increase their degree of resilience to extreme weather events. (Objective) This research was aimed at evaluating the environmental condition of 4 mangrove communities based on the study of soil and vegetation components, through a set of edaphic and dasometric properties, in the Northern area of the Coyuca Lagoon, Mexico. (Methodology) The selection of study and sampling sites considered their spatial representativeness, degree of alteration, and proximity to the coastline. Tree structure and biomass were characterized, and 30 cm-deep soil samples were taken for lab analysis. (Results) Forest inventory showed the presence of the Rhizophora mangle, Laguncularia racemosa, and Conocarpus erectus species, whose distribution is mainly related to the soil hydric regimen, pH, and salinity. Air and soil carbon storage fluctuated between 41.5 and 165 Mg ha-1, being consistent with their degree of disturbance. (Conclusions) The main effects of the anthropic activities were partial loss of forest structure due to slash-and-burn, compaction of the soil’s surface layers, resulting in increased apparent density and reduced carbon stored in biomass and soil.

In montane cloud forests (MCF), the main soil organic carbon (SOC) pool is believed to be constituted by organic debris accumulated on soil surface and, to a lesser extent, by the organic fraction associated with the mineral matrix. The vertical distribution of SOC within soil has strong implications on the composition, stabilization and turnover of the soil organic matter (SOM). In ecosystems like MCF, where the climatic and edaphic conditions varied with altitude, the SOM accumulation and stabilization mechanisms possibly respond to these changes. For that reason, we studied the vertical distribution, accumulation and chemical composition of SOM in five montane cloud forest communities located between 1,500 and 2,500 m a.s.l. Two main SOC accumulation patterns were found: one at 1,500, 1,950 and 2,400 m a.s.l., with SOC content gradually decreasing with depth (cumulative); and another at 2,050 and 2,500 m a.s.l. where SOC had a strong maximum in the surface horizon and a less pronounced increase the spodic horizon (eluviation–illuviation pattern). The total SOC pool in soil decreased in inverse relation to altitude from 227 C ha−1 at 1,500 m a.s.l. down to 143 mg C ha−1 at 2,500 m a.s.l. About 40–60 % of total SOC content corresponded to the surficial organic horizon. The chemical fractionation of the SOM denoted in general predominance of the fulvic acid fraction, and high content of humin and humic acid fractions. We considered that the main SOC vertical distribution processes were related to the raw humus accumulation, decomposition in situ, podzolization in the eluviation–illuviation pattern soils mainly.