Researchers showed that functional traits of plants can help explain why some grasslands remain productive over many years, but are less useful in understanding how ecosystems respond to individual disturbances.
As climate change brings more frequent droughts and increasingly unpredictable weather, one of the biggest questions facing scientists is how ecosystems will respond. While some ecosystems recover quickly from environmental stress, others struggle to remain productive over time. Understanding what makes ecosystems resilient is becoming increasingly important as managers work to conserve biodiversity and sustain ecosystem services in a changing climate.
New research from the KBS LTER, led by former Indiana University PhD student Sierra Perez and KBS LTER Co-PI Jen Lau, explored two decades of data from plant communities within the Main Cropping System Experiment to compare two ways of predicting ecosystem performance under a changing climate. One approach focused on traditional measures of plant communities, including species composition and diversity. The other incorporated functional traits, such as plant height, specific leaf area, and leaf dry matter content, which describe how plants acquire and use resources.
They then evaluated how well each approach predicted two different measures of ecosystem stability. The first was drought resistance, or how much productivity changed during drought years. The second was productivity invariability, which measures how consistently an ecosystem produces plant biomass over many years despite changing environmental conditions.
They found that functional traits did not improve predictions of drought resistance. Simply knowing which species were present and their relative abundance was just as effective at explaining how grasslands responded during droughts.
However, the story was different when looking over the long term. Including functional traits significantly improved predictions of productivity invariability, suggesting that these traits capture important ecological processes that influence ecosystem stability through time. Grasslands dominated by plants with more conservative resource-use strategies tended to maintain more consistent productivity, despite environmental variation from year to year.
The findings underscore how ecosystem stability is not a single characteristic. The mechanisms that allow plant communities to withstand a short-term drought may differ from those that help them remain productive over time. As the climate continues to become more variable, understanding these differences will be important for predicting how ecosystems respond to future environmental change.
This work also highlights the importance of long-term ecological research. Detecting patterns in ecosystem stability requires observations collected over many years, allowing researchers to distinguish temporary responses from long-term trends. By combining decades of ecological data with measurements of plant functional traits, studies like this improve our understanding of how grasslands function today and how they may continue to provide important ecosystem services under future climate conditions.
Perez, S.B. and Lau, J.A., 2026. Functional properties improve predictions of long‐term productivity invariability but not resistance to drought. Ecology, 107(5), p.e70421.