Abstract Detail

Paleobotanical Section

Domínguez De La Torre, Aldo [1], Calvillo-Canadell, Laura [2], López-Gómez, Victor [1], Cevallos-Ferriz, Sergio [3].

Climate reconstruction based on leaf diversity from the Miocene of San Esteban Tizatlán,Tlaxcala, México.

The climate is determinant for plant distribution and foliar physiognomic characteristics that selects plants capacity to live under specific environmental conditions. Based on this relationship, the reconstruction of the paleoclimate that existed during the Miocene in San Esteban Tizatlán, Tlaxcala, in central México, using CLAMP (Climate-Leaf Multivariate Analysis Program) and taxonomic affinities is discussed. The material used in this study includes 70 morphotypes among which Lonchocarpus, Abarema(Leguminaseae), Cyrtopegia (Anacardiaceae), and Rhamnus/Karwinskia (Rhamnaceae) with tropical distribution have been identified. Comparison of CLAMP results and extant data from a meteorological station suggest a marked change in climatic parameters for the zone. During the Miocene a humid warm climate with at least 20°C of mean annual temperature and mean annual precipitation of 3000 mm prevailed, supporting a tropical rain forest. Conditions change through time, establishing a cold, dry climate, that supports since the Plio/Pleistocene pine forests and grasslands. Such a change may be caused by the increase in altitude of the Mexican Volcanic Belt; an event that restricted the distribution of many groups considered of tropical distribution today, from those restricted to the mountains and highlands of Mexico. This hypothesis is supported by other taxonomic studies of wood and leaves, which propose the presence of evergreen elements being, replace by deciduous forests in central Mexico some 12 to 8 mya. Understanding climate is important because it allows us to explain the distribution and diversity of Mexican vegetation.

Broader Impacts:

1 - Facultad de Ciencias, UNAM, Biología, Ciudad Universitaria, Coyoacan, México D.F., 04510
2 - Instituto De Geología, UNAM, Circuito De La Investigación, Ciudad Universitaria, Coyoacan, N/A, 04510, Mexico
3 - Instituto De Geología, UNAM, Department Of Palentology, Ciudad Univwersitaria, Coyoacan, MEXICO D.F., N/A, 01900, Mexico

Keywords:
Miocene
Tlaxcala, Mexico
paleoclimate
CLAMP.

Presentation Type: Oral Paper:Papers for Sections
Session: 31
Location: Union A/Hyatt
Date: Tuesday, July 10th, 2012
Time: 10:45 AM
Number: 31002
Abstract ID:122