By Andrew Berry
Research is being conducted within Bernheim Forest and other Louisville-area forests to study the relationship between human-caused climate change and urban forest functionality and productivity. Previous research indicates that anthropogenic factors, aka environmental pollution caused by human activity like emissions from vehicles, can increase tree growth rate. They can also have a deleterious effect on the social, ecological, climatic, and aesthetic benefits of urban forests.
Assistant Professor of Geography and Geosciences at the University of Louisville, Dr. Maegen Rochner is working to build a network of tree-ring chronologies across Louisville’s urban-rural network. She is collecting cores from white oak trees in urban (Cherokee Park), peri-urban (Jefferson Memorial Forest), and nonurban forests (Bernheim Forest). So far, dendrochronological analysis, the dating of events by annual growth rings in timber, has shown that tree growth at these three sites was strongly associated with summertime moisture and temperatures and that growth and climate sensitivity patterns in urban trees are comparable to those in non-urban trees.
Dr. Rochner and her team will take samples from additional Louisville-area forests to evaluate the relationship between moisture, temperature, and tree growth and investigate potential changes in these relationships due to anthropogenic impacts like the heat island effect.
“We expect that warmer temperatures and longer growing seasons in urban areas may be leading to reduced climate sensitivity in trees by improving overall growing conditions. In short, warmer temperatures and more time to grow equals happy trees. On the other hand, higher urban temperatures could be increasing drought stress in trees, leading to enhanced sensitivity,” explains Dr. Rochner.
You can see the impacts of human-caused climate change in our neighborhoods, parks, and within Bernheim Forest. Observing and analyzing these impacts will help researchers, scientists, and forest stewards understand the implications of climate change locally and develop strategies to protect the thousands of species of plants and animals that call Bernheim home.