MANHATTAN Tallgrass prairies. One of America's most endangered ecosystems.
While their size has diminished over the years only an estimated 5 percent of the original tallgrass prairie in the United States exists today their importance in the ability to predict climate changes has not, according to research conducted by two Kansas State University scientists.
Long-term studies in tallgrass prairies may be able to predict and help researchers better understand how ecosystems across North America might respond to certain aspects of climate change, such as global warming; droughts and changes in precipitation amounts, according to K-State biology professor Alan Knapp. His research, co-authored by Melinda Smith, a doctoral student in biology, is published in the Jan. 19 issue of Science
Knapp and Smith compiled data from 11 long-term ecological research sites across North America, selecting only those sites that had the best and longest-term data on plant growth known as production and precipitation. One of their goals was to determine which biomes, among deserts, grasslands and forests, had more variable production; which biomes responded most to precipitation variability.
"In this study, we were particularly interested in how different ecosystems respond to variations in rainfall," Knapp said. "If rainfall patterns change and variability changes in the future as predicted by climate models how will that affect plant growth and which ecosystems will be the most responsive?"
Knapp and Smith made a simple prediction. If the greatest precipitation variability from year-to-year occurs in deserts and deserts are the most water-limited biomes, then plant growth in deserts would be expected to change dramatically from year-to-year; grasslands would be less variable from year-to-year and forests would be the least variable of all.
Instead the data indicated their hypothesis wasn't supported at all.