Title

The impact of ancient Maya forest gardens on modern tree species composition in NW Belize

Date of Completion

January 2008

Keywords

Biology, Botany|Anthropology, Cultural|Biology, Ecology

Degree

Ph.D.

Abstract

The objective of this dissertation is to assess the impact of ancient Maya "forest gardens"—tree-dominated home gardens containing a diversity of tree species used for daily household needs—on the tree species composition of the extant forests of Northwestern Belize. The central hypothesis is that due to centuries of intensive management, forest gardens built by the ancient Maya altered the tree species composition and that alteration can still be detected today. I hypothesized species composition will be significantly different between areas of dense ancient residential structures (High density) and areas of little or no ancient settlement (Low density). Sixty three 400 m2 plots (31 High density and 32 Low density) were censused around the El Pilar Archaeological reserve in northwestern Belize. All trees greater than 2.5 cm DBH were marked, measured, and identified and their x-y coordinates within each plot mapped. The species composition of High and Low density forest areas was significantly different. There was a greater abundance of forest garden species (species identified from previous studies of useful plants in the region) found in the High density forest. Subsequent edaphic analyses revealed that while there were significant edaphic differences between High density and Low density, this only explained 5% of the species composition differences. ^ The persistence of ancient forest garden tree communities suggests that ancient Maya forest gardeners may have recognized and exploited ecological characters that enhanced the stability of the garden community—synergisms. Using the mapping data, a randomization method for spatial analysis was developed to investigate potential synergistic relationships between forest garden species. The analysis revealed that 58 pairs of species tended to "cluster" together significantly more often in the High density areas than would be expected in a random distribution. In Low density plots, only 12 pairs of species exhibited a significant "clustered" spatial relationship. This research provides data on the long-term impacts of Maya forests gardens for use in development of future conservation models. For Mesoamerican conservation programs to work, we must understand the complex ecological and social interactions within an ecosystem that developed in intimate association with humans. ^