The conservation of the olive ridley turtle (Lepidochelys olivacea) is increasingly critical due to declining global populations. This study investigates the influence of hydrometeorological conditions on the nesting season and annual hatchling sex ratios conducted at the Playón de Mismaloya Federal Reserve in Tomatlán, Jalisco, Mexico. The research specifically examines variations in sand temperature at both the beach surface and nesting depths, with extended measurements taken at multiple depths (20, 40, 60, 80, and 100 cm) to analyze the vertical temperature gradient along the beach. Atmospheric parameters were modeled using Newton’s Cooling Law and solved with the finite difference method to estimate heat loss rates from beach sand to its surroundings, shedding light on microclimatic effects on incubation and embryonic development. Meteorological data were gathered from an automatic weather station, while sand temperatures were monitored with thermographs. During the warm period (approximately 32 °C), sand temperature showed a negative correlation with depth (20–100 cm), indicating cooler temperatures at greater depths. These conditions were associated with female-biased hatchling production. Conversely, the cold period (approximately 28 °C) led to male-biased hatchling production, with a positive correlation between sand and air temperatures. This study emphasizes the importance of monitoring in situ environmental conditions and extending the protection season until February to avoid the loss of male hatchlings.
High-mountain lakes are unique ecosystems with very few examples at tropical latitudes for experimentation. A two-year, high-frequency meteorological and water-column dataset from the crater of the Nevado de Toluca volcano, in Mexico, at an altitude of about 4200 m above sea level, allowed for the study of temporal changes in the thermal structure, water level, and water balance in the Lakes El Sol and La Luna, separated by about 500 m by a lava dome. Annual fluctuations in the water level of the lakes and calculations of the annual variability of the water balance showed that the lakes accumulated almost four times less water from rainfall than expected. Furthermore, the temperature measured at a depth of 15 cm in the bottom sediments of Lake El Sol revealed an unexpected warming during the cold season. Estimated heat fluxes through the lake bottom were less than 0.3 W m−2 during the winter and less than 0.1 W m−2 during the rest of the year. Although the variability of the hydrometeorological regime of high-mountain lakes remains relatively poorly understood, our results significantly improve the understanding of these complex processes of stratification and mixing in these unique lake ecosystems.
This paper addresses the intricate intersection of ecological-political challenges faced by the Mekong River and Tonle Sap Lake, located in Cambodia. To tackle this issue, an exhaustive literature review was conducted, and specific case studies in th...