Human adaptation to mid- to late-Holocene climate change in Northeast Thailand

Abstract

This article integrates palaeoenvironmental and archaeological sequences covering the mid- to late-Holocene in Northeast Thailand. The former reveal the fluctuating intensity of the Asian summer monsoon, leading to periods of higher moisture availability with intervals of relative aridity. The latter are founded on a series of new radiocarbon determinations that provide a basic chronological framework, from the initial Neolithic settlements by rice farmers (c. 3700 cal. BP) to the end of the prehistoric Iron Age around 1300 cal. BP. By dovetailing the two, we find that periods of relative aridity occurred during the later Iron Age as an agricultural revolution witnessed water control measures, plough and irrigated rice cultivation and a marked rise in social elites. The correlation between climatic and cultural changes is found to continue into the period of the Angkorian state. Rather than cause a decline and/or abandonment of late Iron Age settlements, we find that the environmental stress caused by a weaker summer monsoon was met by a strong social response and by adaptations that generated a transition into early socially hierarchic polities.

First human impacts and responses of aquatic systems: A review of palaeolimnological records from around the world

“…Archaeological information found around the sites provides a chronological framework, from the initial Neolithic settlements by rice farmers (c. 3700 b2k) to the end of the prehistoric Iron Age around 700 ce (Wohlfarth et al, 2016). A palynological study of wetlands in the Song Hong (Red River) Delta (Vietnam) suggests that cultivation intensified in this region from 3340 b2k, as revealed by high abundance of cultivated rice (Oryza sativa) pollen (Li et al, 2006).…”

A Bioarchaeological Study of Trauma at Late Iron Age to Protohistoric Non Ban Jak, Northeast Thailand

“…Paleoenvironmental evidence from the Khorat Plateau indicates a decline in moisture from the mid-second century B.C., with increasing dryness and low seasonal rainfall between the first and eighth centuries A.D. affecting dry rice production; this corresponds with the Iron Age occupation of Non Ban Jak (Boyd 2008;Boyd and McGrath 2001;Castillo et al 2018;Wohlfarth et al 2016). Coping mechanisms for environmental change in northeast Thailand included the construction of moats around mounded sites in the Mun River Valley, including at Non Ban Jak.…”

First Farmers in Mainland Southeast Asia

“…At this same juncture, we find wealthy elite burials in graves ritually filled with rice (Higham and Thosarat 2007). The presence of wetland weeds strongly suggests cultivation in well-watered fields (Higham 2011, Castillo 2014, Wohlfarth et al 2016). Collectively, these changes have been described as an agricultural revolution (Higham 2014).…”