Climatic changes, settlement dynamics, resourcescape, and landscape evolution in the Delice Valley (Çorum) during the Early and Middle Holocene

Abstract

Non-linear, complex, and feedback-driven interaction networks exist between archaeological communities and the landscapes they inhabit. These interactions are increasingly being explored and modeled by archaeologists, anthropologists, and other scholars through landscape archaeology and ecological anthropology, combined with computational methods and agent-based simulations. The strong interdisciplinary collaboration between archaeology and the geosciences has significantly contributed to this growing field of study. This dissertation investigates how humans and landscapes co-evolved within the Delice Valley by adopting a theoretical framework rooted in ecological anthropology and landscape archaeology. To this end, an integrated methodological approach—combining Geographic Information Systems (GIS), remote sensing, and geomorphological analysis—was employed to spatially model, map, simulate, and interpret long-term socio-ecological processes. The study area, Delice Valley, is located in north-central Anatolia and has been shaped since the Pleistocene by one of the major tributaries of the Kızılırmak River—the Delice River. At its confluence with the Kızılırmak (ancient Halys), the river forms a wide floodplain characterized by thick alluvial deposits. These alluvial zones constitute fertile lands with high agricultural potential for both modern and pre- and proto-historic farming communities. The paleoclimatic history of the Delice Valley has been reconstructed using the CHELSA TraCE21k global circulation model, the synoptic Macrophysical Climate Models (MCM), and hydroclimatological proxy datasets. The findings indicate that cool and humid climatic conditions prevailed throughout the Early and Middle Holocene, while warmer and drier conditions became more prominent from the mid-Middle Holocene onward. The settlement history of the Valley spans from the Chalcolithic period (ca. 6000 cal. BP ) to the Iron Age (ca. 2600 cal. BP). Using advanced GIS-based spatial analysis tools, the spatial and temporal patterns of settlement were examined. During the Chalcolithic period (n=13), the dispersed settlement pattern reflects the early stages of socio-political organization. In the Early Bronze Age (ca. 5000–4000 BCE; n=107), the emergence of polity-like structures corresponds with a more clustered settlement pattern. During the Iron Age (ca. 3200–2600 BCE; n=60), following the collapse of the Hittite Empire, a return to dispersed settlement is observed. Notably, during the Early Bronze Age, settlements tend to cluster near fertile agricultural plains and key natural resources such as salt and copper. Following the paleoenvironmental reconstructions, landscape evolution was modeled using the MedLanD model within a GrassGIS environment. The model assessed how archaeological agro-pastoral communities affected their surroundings—such as through erosion and land cover changes—under different land use strategies and climate change scenarios, as well as the resilience of these systems. The model was specifically applied to Resuloğlu Höyük (4300–4100 BCE), one of the prominent sites among 206 settlements in the study area. The MedLanD Modeling Laboratory (MML) yielded results that are consistent with Resuloğlu's archaeological record, geomorphological context, and socio-political organization. Due to the badlands-like geological character of the region, rainfall was identified as the primary driver of natural landscape evolution. Under human-influenced conditions, livestock pressure and overgrazing dominated during dry periods, whereas agricultural activities became the main drivers under wetter conditions. This study aims to safeguard the cultural memory and heritage of Resuloğlu Höyük through the use of integrated GIS, remote sensing, and geomorphological approaches. A comprehensive erosion modeling study was conducted using GeoWEPP (a GIS-based Water Erosion Prediction Project), supported by SPOT 7 satellite imagery, drone surveys, field observations, and expert interviews. The results demonstrate that archaeological excavations—particularly in a context of high erosion risk—have intensified erosion processes on the mound. These findings highlight the urgent need for local authorities to adopt immediate and effective conservation policies to prevent further degradation. Ultimately, the research shows that socio-political organization, subsistence strategies, resource exploitation, and long-distance trade were critical factors influencing the long-term evolution of settlement systems in the region.