Abstract: Increasing environmental stress has exacerbated diversity and productivity declines in natural forests. Sprouting, as an important form of clonal regeneration in woody plants, may enhance persistence and regrowth under environmental stress, and potentially contribute to the maintenance of species diversity and productivity. However, doubts persist regarding the influence of sprouting on species loss and productivity in natural forests. Here, we examined how environmental stress and tree sprouting were associated with species loss rate and aboveground productivity in natural forest communities, based on 10-yr growth and survival rates of woody plants with over 22,000 sprouting individuals in a subtropical forest in eastern China. Three indices (proportion of sprouting species, proportion of sprouting individuals and sprout ratio) were used to measure both sprouting prevalence and sprouting intensity of forest communities at three different quadrat sizes. We confirmed that quadrats under higher stress pressure exhibited increased species loss and decreased aboveground productivity. We also discovered that quadrats with higher sprouting displayed significantly lower species loss rate and higher aboveground productivity. Additionally, both sprouting prevalence and intensity of quadrats significantly increased from 2010 to 2020. These results remained robust across various sprouting indices and quadrat sizes. Our findings highlight the potential role of sprouting, an often-overlooked functional trait of woody plants, in contributing to the maintenance of species diversity and aboveground productivity under increasing environmental stress. We argue the importance of considering tree sprouting in future studies to better understand responses of plants and forests to climate change.

Key words: species loss, sprouting, stress, Tiantong, persistence niche, productivity