Evaluating the Indian Summer Monsoon intensity using archeological seeds from early–late historic Vidarbha,Central India

We present an archaeobotanical record representing ~2300 years BP farming practice at Nagardhan an Early Historic—Late Medieval site in the Vidarbha region, Maharashtra, central India. The study assesses the crop harvesting patterns and Indian Summer Monsoon (ISM) intensity using two different approaches (archaeobotany, and canonical correspondence analysis) to understand the variability and impact of ISM on human subsistence systems during periods of dynastic transition. Our results show a gradual transformation from a warm-humid climate during the Early Historic and Historic (300 BCE–1200 CE) with the dominance of large-grained cereals (C₃ plants); to dry climate during the Medieval and Early Modern periods (1200–1900 CE) due to weakening of southwest monsoon (SWM) as evidenced by the dominance of small-grained millets (C₄ plants). The changing crop assemblage and cultural developments in this area of central India provide insights into past human responses to climate change and provide insights for modern societies in exploring sustainable agricultural policies during the ongoing climate deterioration. Moreover, the present study provides insights into the Indian Summer Monsoon (ISM) rainfall variability during the Late-Holocene in global climate change perspectives from one of the poorly understood areas of the tropics in Southeast Asia where the rainfall is essentially controlled by the ISM.