Investigations of Atmospheric and Plant Physiological Effects along an Urban-To-Rural Gradient in the Houston Metropolitan Area Comparing 2011 to 2012

This project hypothesizes that changes in climate resulting from urbanization can serve as a proxy for the changes expected from climate change, and therefore, future climate change effects on the biosphere can be estimated by comparing urban trees to rural trees. To study this, an urban0to-rural gradient was set up starting near downtown Houston, TX, and extending north approximately 90 km. Three weather stations were erected along this gradient to continually monitor weather. Photosynthesis rates of oak trees near each weather station were measured on periodic field trips throughout the growing season.

Comparisons of temperature, rainfall, carbon dioxide, and ozone concentrations indicate that urbanization is a possible but imperfect proxy for climate change. Considering only two years of photosynthesis measurements, the long term effects of climate change are difficult to distinguish from short term effects, such as rain, and seasonal term effects, such as drought. However, observations hold promise that further measurements may lead to more conclusive results.