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Besides supporting a diverse number of species and habitats, the ecosystem of the Bull Creek Nature Preserve also provides several services that benefit the human residents of Austin.

One major benefit is the improvement of water quality. Surface water runoff from urban and paved areas may contain pollutants such as metals, oils, sediment, and excess nutrients. The vegetation and soil of the Preserve act as a natural filter, intercepting and absorbing water flows as well as storing and transforming pollutants. This process reduces stormwater runoff during rain events and helps to purify the water entering creeks and rivers, as well as that which percolates into underground aquifers.

Another benefit provided is the improvement of air quality. Trees and other vegetation in the Bull Creek Nature Preserve remove several pollutants from the atmosphere, including carbon monoxide, sulfur dioxide, nitrogen oxides, ozone, and particulate matter. Through photosynthesis, vegetation can also remove and store carbon dioxide—a greenhouse gas believed to contribute to global climate change. These air quality benefits from the preserve areas help to offset air pollution from additional traffic and other results of growth in Austin.

A third benefit has to do with local climate. Due to the large amounts of heat-absorbing surfaces (buildings and asphalt) as well as high-energy use, temperatures in urban areas are often significantly higher than in rural areas. This phenomenon is known as the urban heat island effect. Trees and vegetation in the preserve areas transpire—meaning water is taken up through the roots and released into the atmosphere through the leaves as water vapor. This process can create a cooling effect resulting in a lowering of local temperatures that helps to combat the urban heat island.

A final benefit of the Preserve ecosystem includes the intangible values we can derive from Nature. The Preserve can provide natural and scenic beauty, spiritual and artistic inspiration, opportunities for learning and knowledge, and a unique heritage for future generations.