Wet season carbon (δ13C) and nitrogen (δ15N) composition of modern plants as isotopic framework for agropastoral and palaeoecological studies in Northern Greece

Mediterranean wetlands are one of Europe's most vital and endangered biodiversity hotspots. This study determined the carbon (δ13C) and nitrogen (δ15N) isotope values of modern plants to construct an isotopic framework by which to contextualize agropastoral management in and around past wetland ecosystems. Dispilio is a Neolithic site (5700–3600 cal bce) on the shore of Lake Kastoria, western Greek Macedonia, where ongoing studies are exploring the nature and scale of livestock management and its implications for understanding how early farming communities adapted to wetland and upland ecosystems. In order better to interpret the stable isotope values of faunal bone collagen from the site in terms of animal diet, habitat use, and feeding strategies, this study examines the carbon and nitrogen isotopic composition of 126 wild plants from 12 localities within the Dispilio catchment area and one proxy location on neighboring Lake Prespa. The plants were collected at the end of the wet season across different habitat types, and the influence of precipitation and altitude was considered. The results indicate a high variability of plant carbon and nitrogen isotope values in the environment. The δ13C values differ amongst life forms (trees/shrubs, grasses, and herbs) with implications for distinguishing the feeding habits and anthropogenic management of domestic grazers and browsers. Furthermore, δ15N values of terrestrial and wetland habitats differ significantly, demonstrating the potential to distinguish isotopically between the use of these landscapes in the past. This study will serve as the first stable carbon and nitrogen isotopic framework for agropastoral, palaeodietary, and palaeoecological studies in northern Greece.