Comparison of vegetation succession patterns in the monsoon and arid regions of northern China over the past two centuries: Implications for ecosystem restoration projects

Understanding vegetation responses to climatic and anthropogenic changes is important for predicting future ecosystem trajectories and informing restoration projects in northern China. In this paper, we report high-resolution pollen records from Lake Gonghai (monsoon region) and Lake Yueliang (arid region) to investigate the relationship between vegetation, climate, and human activity over the past two centuries. Prior to 1900 CE, Lake Gonghai supported abundant arboreal vegetation under humid conditions, with extensive pastoralism indicated by high coprophilous fungal spores. During 1900–1960 CE, increasing aridity and social instability led to vegetation degradation and reduced pastoral intensity. After 1960 CE, ecological restoration policies promoted vegetation recovery, accompanied by a shift from pastoralism to Hippophae-dominated cultivation. In contrast, vegetation succession at Lake Yueliang has remained primarily climate-driven. Before 1900 CE, Artemisia–Tamarix desert–steppe communities prevailed under relatively humid conditions. During 1910–1990 CE, rising aridity induced a transition toward Amaranthaceae–Nitraria communities. After 1990 CE, persistent drought stabilized xerophytic vegetation composition. We suggest that vegetation dynamics across a large spatial scale have been (1) more strongly influenced by human activities in the monsoon region, with anthropogenic impacts intensifying since 1960 CE, and (2) primarily driven by climate in the arid region, with a west–to–east transition from warming–wetting to warming–drying. Our findings emphasize divergent regional ecosystem trajectories and the need for restoration strategies tailored to distinct climatic and anthropogenic contexts in northern China.