Measuring the diameter of a tree in the Rio Bravo Conservation and Management Area


To read a funded proposal on the effect of the ancient Maya on the modern forest see the proposal summary below and follow the link for the full proposal:  maya-forest-proposal.  To read a popular article about this research follow the link:

Proposal summary

Our research question is:  How has land use of the ancient Maya affected the present forest?  To help answer this question we use an interdisciplinary approach and ask linked questions:

Archaeological question:  What were the land uses of the ancient Maya?

Geo-archaeological question:  How have those ancient land uses affected topography and soil today?

Ecological question:  How has ancient Maya land use and its impacts on topography and soil today affected the structure and tree species composition of the modern forests?

Our approach is to study archaeology, geo-archaeology, and tagged-drypetes-brownii-img_2612ecology at the same sites and correlate the results to connect ancient land use to the present forest.  The ecological method is to determine the tree species composition in two hundred 400 m2 plots and relate that composition to ancient land use, topography, and soil in the plots.   The research takes place in two study areas in the Rio Bravo Conservation and Management Area, Belize.




Tagged study trees.  Upper: Drypetes brownii (male bullhoof); lower: Pouteria reticulata (zapotillo); two of the most abundant species in upland forest (among trees ≥ 10 cm diameter)

The goal of this research is to understand how forests of the Rio Bravo Conservation and Management Area (RBCMA) are changing.  That will help us predict the future state of the forests for conservation and management purposes.  In 1991 we established four 1-ha plots in RBCMA forests, one each in moist upland forest, dry upland forest, riparian forest, and cohune palm forest.  In each plot we tagged, mapped, measured for dbh (diameter at breast height), and identified to species all self-supporting woody stems ≥ 10 cm dbh.  We are re-censusing these plots to record mortality, recruitment, and growth of surviving stems.  These data will tell us how fast the trees are growing and how the species composition of trees is changing.  We also are studying smaller stems, between 1.0 and 10 cm dbh, in order to characterize the forest understory and look at potential regeneration indicated by the presence of saplings and pole-sized trees.  In addition we record data on epiphytes, lianas, and juvenile palms.