Reconstruction of paleoclimate and ecosystem changes in Western Iran using cave sediments from the Mid-Holocene Epoch (Northgrippian Age)

This study investigates paleoclimate and ecosystem changes during the Mid-Holocene Northgrippian Age in Western Iran, using geochemical analysis of sedimentary layers from Qalucheh Cave, Kurdistan Province. A 77 cm sediment sequence was analyzed, spanning approximately 1740 years (4140–5880 years BP), with radiocarbon dating confirming its chronological framework. Through XRF analysis and key geochemical proxies such as Mg/Ca, Sr/Cu, Rb/Sr ratios, and elemental concentrations (Zr, Ba, Ti), three distinct climate phases were identified. Stages A (4140–4700 years BP) and C (5400–5880 years BP) reflect humid conditions with dense vegetation, high organic carbon levels, and minimal aeolian activity. Conversely, Stage B (4700–5400 years BP) is characterized by arid conditions, reduced vegetation, high dust input, and significant ecosystem degradation. The findings highlight the interplay between climate fluctuations and ecosystem dynamics, emphasizing the critical role of climate in shaping vegetation cover, soil fertility, and water availability. This study also explores the implications of these environmental changes on human settlements and societal adaptation strategies, such as water management and agricultural innovations, which helped mitigate the adverse effects of arid phases. The research underscores the importance of cave sediments as invaluable archives for reconstructing past climate and environmental conditions, offering insights into the resilience and adaptability of ecosystems and human communities during climatic transitions.