Late Holocene Climate Variability in the Southern Maya Lowlands

The possible role of climate change in the abandonment of the southern Maya lowlands has received considerable attention. Studies from the northern Maya lowlands have shown significant late Holocene climate variability and, specifically, a pronounced dry period from ~A.D. 800-1000 coinciding with widespread abandonment of the southern Maya lowlands in the Late Classic period. Here we present a 5000 year record of climate change and human activity from Lago Puerto Arturo, a lake in northern Peten, Guatemala. Paleoenvironmental proxies include stable isotopes, pollen, magnetic susceptibility and LOI. Our findings both corroborate and expand upon previous studies from the Maya lowlands. Preliminary data show relatively dry conditions during the period of settlement and agriculture, from ~2650 B.C. to A.D. 900. A peak of δ¹⁸O values indicates particularly dry conditions during the Late Classic period, similar to results from lakes Chichancanab and Punta Laguna in the northern Maya lowlands. Anthropogenic disturbance and the presence of Zea pollen throughout this period, however, suggest drought did not cause regional abandonment. Shortly after A.D. 900, δ¹⁸O values drop dramatically, indicating a shift to wetter conditions. Concurrent with this shift is a cessation of agricultural activity and human disturbance. These results suggest it was not until wetter conditions set in that the southern Maya lowlands were abandoned and that the previous relatively dry climate may have been optimum for prehistoric agriculture in the lowlands.