Plant ecophysiogical approaches are suitable for characterizing plant species based on their drought resistance. However, plant ecophysiology is almost never combined with archaeological or ethnobotanical studies, even though many unresolved questions within the field of anthropology revolve around the collapse of ancient civilizations in the face of drought.
To estimate how the availability of food plants varied during different drought intensities, we evaluated the drought resistance of all 497 indigenous food plant species documented in ethnographic, ethnobotanical, and botanical studies as having been used as food by the lowland Maya, and classify the availability of these plant species and their edible components in simulated drought scenarios.
We used the case of the collapse of Classic Maya civilization to implement this approach since the collapse coincided with droughts of strong magnitude, but paleoclimatic data lacks the resolution to determine whether droughts were intense enough to affect food production. Drought resistance was based on well-established plant functional traits.
Our results show availability of 83% of food plant species in short term drought, 22% in drought up to one year, and 11% during intense drought, lasting several years. These results indicate that short-term or moderate droughts would have caused agricultural disruption, but potential agricultural collapse would have been restricted to intense multi-year droughts only.
Overall, our experience suggests that plant ecophysiological techniques are appropriate for archaeological studies and can constrain the availability and utility of plant species under simulated climate scenarios. Further work in the integration of plant ecophysiology and archaeology lie in the quantitative characterization of drought resistance of useful plants of ancient civilizations to construct environmental responses of ethno-floras to past climate anomalies.
Maya drought climate P50 turgor loss water potential ancient diet