A 110-year pollen record of land use and land cover changes in an anthropogenic watershed landscape, eastern China: Understanding past human-environment interactions.

Land use and land cover changes (LUCCs) have largely altered terrestrial ecosystems and landscapes during the Anthropocene. Reconstructing past LUCCs is necessary to better understand terrestrial ecosystem succession and human-environment interactions so that ecosystem services can be used conservatively and developed sustainably. In this paper, we reconstructed the LUCCs over the past century in a typical anthropogenic watershed based on a high-resolution pollen record from Changdang Lake, eastern China. The sediment core was Pb dated and constrained cluster analysis identified different periods of LUCCs associated with the 110-year pollen record. Multi-sedimentary proxies, historical records, and remote sensing LUCC maps were analyzed to complement the palynological results. Our results demonstrate that pollen records can accurately capture LUCCs during different historical periods. Extra-regional arboreal pollen, fern spores, and pollen concentration can record the hydrological variations of waterbodies under both climatic and anthropogenic impacts. Multiple agriculture-related pollen indicators, such as cereal, Cruciferae, and wetland taxa are significantly related to the corresponding vegetation cover and landscape variations. Specifically, the anthropochore taxa to wetland taxa ratio is a good indicator of agricultural intensity. Dominant arboreal pollen (Pinus and Quercus) and the arboreal taxa to non-arboreal taxa ratio reflects the forestry landscape changes. Urban greening arboreal pollen (including Platanus, Salix, and Ulmus) is found to be an indirect indicator of urbanization. In addition, agriculture and urbanization in the region are causing the pollen diversity to increase in lake sediments. This study from a shallow lake in eastern China contributes to our understanding of pollen-based LUCC studies in similar climatic and anthropogenic regions around the world.