Mangrove forests of Mexico have been threatened by the effects of anthropogenic activities during the last decades, mostly related to aquaculture, agriculture, livestock and urban development. Genetic diversity and fine-scale genetic structure of two generations of the black mangrove Avicennia germinans (L.) Stearn were investigated in perturbed and preserved sites from three lagoon systems in Sinaloa, Mexico. Genetic diversity and overall genetic structure were similar between perturbed and preserved sites. However, lower levels of fine-scale spatial genetic structure were observed in two of the younger (sapling) generations. We attribute this to differences in local dynamics of each lagoon system, their status of conservation and levels of fragmentation. Also, low connectivity and the effects of disturbance could restrict the movement of pollinators and seed dispersal capabilities, resulting in low levels of genetic diversity and signs of inbreeding. Perturbed populations of A. germinans may play an important role in in situ conservation of this complex ecosystem.

El acelerado crecimiento de la población humana en las últimas décadas ha llevado a un aumento en la tecnificación industrial, generando grandes cantidades de contaminantes, como aguas residuales, desechos sólidos y emisiones gaseosas. Estos contaminantes, al no recibir un tratamiento adecuado, pueden dañar el ambiente y la salud humana. Para mitigar estos efectos, se han desarrollado estrategias como la biorremediación, que emplea organismos como bacterias, hongos, algas y plantas para rehabilitar entornos contaminados por metales pesados, hidrocarburos, pesticidas y plásticos. Aunque no es una tecnología nueva, su continua actualización a través de la investigación y la incorporación de nuevos organismos específicos para cada ecosistema es crucial. Una estrategia prometedora es el uso de mangles, plantas altamente tolerantes a altas temperaturas y salinidad, que muestran un gran potencial en la biorremediación de ecosistemas costeros contaminados por metales pesados.

Changes in the structure and composition of mangroves may be influenced by anthropogenic and natural causes. Mangrove coverage in Marismas Nacionales Nayarit –a Biosphere Reserve in northwestern Mexico—has declined in the last decades, mostly related to human activities (e.g., opening of the Cuautla inlet) and climate variability (e.g., El Niño Southern Oscillation and hurricanes), leading to diverse ecological and socioeconomic consequences. This contribution reports the impact of Cissus verticillata—a climbing plant species—in the structure of mangroves distributed in this Natural Protected Area during 2019 and 2022. Forest structure analysis was compared in four plots of 20 m × 20 m each, all of them influenced by San Pedro Mezquital river. Two plots (Unión de Corrientes) showed the presence of Cissus verticillata, while two nearby plots (Boca de Camichín) recorded no presence of this species. A poor mangrove structure, no natural seedling recruitment and high mortality was observed in those sites with the presence of C. verticillata. These results highlight the vulnerability of mangroves to C. verticillata in Marismas Nacionales Nayarit Biosphere Reserve, which in addition to other human and climate stressors may compromise its ecological integrity in the future.

Mangrove wetlands in northwestern Mexico have been highlighted due to their ecological relevance and ecosystem services. This study evaluated the mortality and natural regeneration of mangroves located in six coastal lagoons in Sinaloa, considering five plots each (400 m²), during a warm–strong (2015–2016) and cold–weak (2017–2018) El Niño–Southern Oscillation. The highest mean mortality was recorded in Huizache–Caimanero—the southern coastal lagoon—during the second stage (390 stems ha⁻¹; 22% corresponding to logging). While an increasing latitudinal (north–south) mortality trend was observed, differences between sites and stages were not statistically significant. Natural recovery was also observed due to higher abundance of seedlings, e.g., the largest increase from one stage to another was recorded in Santa María–La Reforma. Mortality and seedling regeneration are discussed in this study, particularly in relation to anthropogenic stressors, logging, and climate variability.