Effects of late Holocene climate variability and anthropogenic stressors on the vegetation of the Maya highlands
Por:
Franco-Gaviria, F., Correa-Metrio, A., Cordero-Oviedo, C., Lopez-Perez, M., Cardenes-Sandi, G. M., Romero, F. M.
Publicada:
1 jun 2018
Resumen:
Climate variability and human activities have shaped the vegetation communities of the Maya region of southern Mexico and Central America on centennial to millennial timescales. Most research efforts in the region have focused on the lowlands, with relatively little known about the environmental history of the regional highlands. Here we present data from two sediment sequences collected from lakes in the highlands of Chiapas, Mexico. Our aim was to disentangle the relative contributions of climate and human activities in the development of regional vegetation during the late Holocene. The records reveal a long-term trend towards drier conditions with superimposed centennial-scale droughts. A declining moisture trend from 3400 to 1500 cal yr BP is consistent with previously reported southward displacement of the Intertropical Convergence Zone, whereas periodic droughts were probably a consequence of drivers such as El Niño. These conditions, together with dense human occupation, converted the vegetation from forest to more open systems. According to the paleoecological records, cultural abandonment of the area occurred ca. 1500 cal yr BP, favoring forest recovery that was somewhat limited by low moisture availability. About 600 cal yr BP, wetter conditions promoted the establishment of modern montane cloud forests, which consist of a diverse mixture of temperate and tropical elements. The vegetation types that occupied the study area during the last few millennia have remained within the envelope defined by the modern vegetation mosaic. This finding highlights the importance of microhabitats in the maintenance biodiversity through time, even under scenarios of high climate variability and anthropogenic pressure. © 2018 Elsevier Ltd
Filiaciones:
Posgrado en Ciencias de la Tierra, Universidad Nacional Autónoma de México, Coyoacán, Ciudad de México, Mexico
Instituto de Geología, Universidad Nacional Autónoma de México, Coyoacán, Ciudad de México, Mexico
Escuela Centroamericana de Geología, Universidad de Costa Rica, San José, Costa Rica
Posgrado en Ciencias Biológicas, Universidad Nacional Autónoma de México, Coyoacán, Ciudad de México, Mexico
Univ Nacl Autonoma Mexico, Posgrad Ciencias Tierra, Mexico City 04510, DF, Mexico
Univ Nacl Autonoma Mexico, Inst Geol, Mexico City 04510, DF, Mexico
Univ Costa Rica, Escuela Ctr Amer Geol, San Jose, Costa Rica
Univ Nacl Autonoma Mexico, Posgrad Ciencias Biol, Mexico City 04510, DF, Mexico
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