The woody vegetation in 317 plots totaling 3.17 hectares was sampled in the forest of the Calakmul Biosphere Reserve, Campeche, Mexico. All stems greater than 2.5 cm diameter at breast height were measured; diameter and vernacular name (Maya or Spanish), along with scientific name, if known in the field, estimated height, slope, presence of ruins, and soil type were recorded. A total of 16,113 stems were measured, representing 138 taxa in 44 families; 105 taxa were identified to species level, 24 to genus, and 5 to family. Vines were only counted as a life form, due to the difficulty of securing specimens for determination. Three uncommon taxa were not identified, described only by Maya common name. Using Maya soil classification terminology, data were used to describe major plant communities on the most important soil types, and to develop an Indicator Species Analysis. Six possible Indicator Species were analyzed by an autobinomial regression, using a Gibbs sampler based on the Markov Chain Monte Carlo method, to test the statistical significance of the Indicator Values. The coefficients for three species were positive and statistically significant; the coefficients for two species were negative and statistically significant; and the coefficient for one species was not statistically significant Brosimum alicastrum (Moraceae) (n.v. ramon) was the dominant tree (measured in square decimeters per hectare) overall (all plots on all soils considered together), and was also the dominant tree on yaxhom (upland) soil, near ruins, on ruins, and on kakab, an anthropogenic soil created by many centuries of human activity on the site. Indicator species analysis showed B. alicastrum to be a strong indicator for the presence of ruins and anthropogenic soil, taking into account neighbor effects. Talisia olivaeformis and Manilkara zapota also show a significant positive association with ruins and the areas around ruins. T. olivaeformis is an important fruit tree in the Yucatan Peninsula today, and was undoubtedly so in antiquity. M. zapota yields fruit, latex, and a very hard, durable wood. The autobinomial regression technique confirmed the statistical significance of the indicator values. Haematozylum campechianum (Leguminosae) was the dominant tree on akalche soil, which is found in lowland seasonal swamps (bajos) The findings, including plant community demographics, statistical and graphic techniques, and historical and archaeological evidence, provide confirmation for the thesis that Brosimum alicastrum is a strong and reliable indicator of sites of former human habitation. These findings also support the hypothesis that B. alicastrum was managed and selected by the Lowland Maya as a staple food. The importance of B. alicastrum as a reliable food source in ancient times, especially before the introduction of Zea mays into the Maya lowlands, probably led to the intensive cultivation, management, and artificial selection of the species. The ramon on the site in modern times likely represents a population which has co-evolved in response to large-scale changes in the landscape and ecology of the forest of southern Campeche and nearby areas. Therefore, the abundance of B. alicastrum on ruin sites can be most parsimoniously explained as a kabab effect, rather than a ruin effect / acase@tulane.edu
| Identifer | oai:union.ndltd.org:TULANE/oai:http://digitallibrary.tulane.edu/:tulane_24901 |
| Date | January 2005 |
| Contributors | Brown, Jon Christopher (Author), Darwin, Steven P (Thesis advisor) |
| Publisher | Tulane University |
| Source Sets | Tulane University |
| Language | English |
| Detected Language | English |
| Rights | Access requires a license to the Dissertations and Theses (ProQuest) database., Copyright is in accordance with U.S. Copyright law |
Page generated in 0.0132 seconds