Resumen

GUTIERREZ-AYALA, Luz Verónica; TORRESCANO-VALLE, Nuria  y  ISLEBE, Gerald Alexander. Late Holocene paleoecological reconstruction of the Los Petenes reserve, Yucatán Peninsula, México. Rev. mex. cienc. geol [online]. 2012, vol.29, n.3, pp.749-763. ISSN 2007-2902.

Changes in climate and ecological dynamics of the Biosphere Reserve of Los Petenes, located in northwestern Yucatan Peninsula, were identified through high-resolution pollen analysis of a core of 2.2 m depth. The reconstruction of the history of vegetation, hydrology and climate that occurred during the last 4000 years was based on fossil pollen analysis, total organic carbon (TOC) and calcium carbonate (CaCO₃). The results show changes in the stratigraphy and the percentage of mangrove elements, wich are interpreted as rapid increases in sea level during the middle to late Holocene transition (4095 - 3100 cal BP). From 3000 cal year BP, considerably decreases of mangroves and changes in COT, suggest a strong hydrological variability. Increase of the tropicalforest and disturbance elements shows changes in the distribution of vegetation. The landscape is dominate by tropical forest and secondary vegetation. The accumulation of gastropods and foraminifera, reveals marine transgressions, and periods of deacresed precipitation and sea level. High percentages in the carbonate signal (12, 20 and 40%), mangrove elements and fungal spores decrease, disturbance elements and Cyperaceae increase, indicating around 600 cal dC, the decrease in precipitation and climatic deterioration is significant. The changes, coincide with changes in other circumcaribbean signals, associated with the Medieval Warming and the minimum of solar activity, recorded during the Little Ice Age. The paleoenvironmental record provides information about the environmental history of RBLP, establishing bases for understanding ecological processes and the implications they may have for conservation.

Palabras llave : climate variability; Late Holocene; Los Petenes; Yucatan Peninsula; fossil pollen; sea level.