ENVIRONMENTAL SERVICES OF VEGETATION IN URBAN ECOSYSTEMS IN THE CONTEXT OF CLIMATE CHANGE

Abstract

There is abundant information on environmental issues that affect the most important cities of the world, but it is limited in Mexico. This reveals that the environmental services provided by urban vegetation, particularly trees, contribute to reduce emissions of greenhouses gases, temperature as well as the intensity of both heat island and heat weaves, but those environmental services provided by the vegetation are limited by the scarcity of water and air pollutants, situation that will exacerbate with climatic change. The main effects of climatic change in cities is the increase in temperature, the formation of both heat weaves and heat islands, increased concentrations of ozone (O3), where O3 is the main hazard, because it affects both human health and photosynthesis, a process important in providing environmental services. Urban vegetation can be a source of air pollution by producing volatile organic compounds, since they produce O3. Both climatic change and heat weaves accelerate the formation of these volatiles. Guadalajara city is affected by climatic change and is vulnerable because it has low percentages of vegetation cover, high air pollution and declining availability of water. Studies of photosynthesis in trees growing in Guadalajara revealed differences in their ability to sequester carbon. Thus, there is a prospective potential to select tree species to be used for reforestation of this city, with the aim to reduce urban air pollution and to mitigate the effects of climate change.