PS 39-61 - Vegetation, phenology, temperature feedback in grasslands

Abstract: Global land surface models predict that surface temperatures could increase by up to 5.4°C by the year 2100. These large changes in temperature will affect plant community composition, structure, diversity, and productivity in unprecedented ways. Changes in mean temperatures and shifts in seasonal temperature patterns within ecosystems will likely affect temperature-sensitive plant phenological processes which may decouple species interactions between plants and pollinators. Vegetation has the capacity to buffer ecosystems against changes in temperature and humidity. Here, we collected plant phenology data on emergence, leaf area, and flowering phenology of eight herbaceous species at four levels of plant diversity in the BioCon experiment at Cedar Creek, Minnesota. We then quantified developmental stages for each plant at three dates over the course of a single growing season. Using this methodology, we determined that plants growing in the lower diversity plots flowered earlier and completed their growing season earlier than plants growing in higher diversity plots. This was correlated with higher temperatures and lower relative humidity in lower diversity plots. Our results suggest that loss of biodiversity in grasslands could further drive asynchrony between plants and their pollinators and further reduce biodiversity over time.