Tree Growth And Urbanization

Throughout history, trees have played a role in humans’ lives, not just actively but passively as well. In the past trees were mostly a resource to be cut down and used to build, but today with global pollution rising, they are more important than ever to combat rising CO2 levels. Forests are being knocked down to make way for suburbs and cities, but still trees find a new home amidst the urbanization. Topics to be considered in urban tree growth are effects of trees on society, the rate of growth of trees in the wild, and the influence of urbanization on trees. (Gellar, Thomas & Nation Research Council 2013; Gregg, Jones & Dawson, 2013; Texas Parks and Wildlife Department [TPWD]) It is hypothesized that urbanization will negatively affect rate of growth in trees. The following literature reviews will attempt to support and oppose the …show more content…
It is hypothesized that rural trees will grow better than urban trees. The study used Eastern cottonwood, a fast growing tree and had similar amounts of precipitation, light. Both trees were planted in a field with little interference of light, both received water through drip irrigation and both received the same type and amount of soil. However the urban tree was exposed to many more pollutants than the rural tree. The result of the study contradicted the hypothesis that urban trees would grow slower. The results show that the urban cottonwood grew nearly twice that height of rural cottonwood. The study found that the amount of biomass (total mass of an organism) was inversely related to the amount of O3 the tree received. The more O3 the trees absorb the less biomass. However, pollutants had no effect on plant growth as previously thought. The results contradict my hypothesis as well that an urban environment will negatively affect tree