The Impacts of Urbanization on the Hydrology of Wetlands: A Literature Review
This literature review provides a synthesis of the current research regarding the hydrological impacts of urbanization on wetlands. The goal of the review is to identify gaps in current knowledge and support the development of a guideline to protect the hydrology, water quality and the ecological function of wetlands through the urbanization process.
This literature review identified several urbanization impacts to wetlands which were shown to affect the ecological function and the biological communities.
1. Hydrological impacts included changes to water level fluctuations, changes in ponding and alterations to the groundwater regime through loss of recharge in developed areas.
2. Water quality impairments included an increase in toxic metals, hydrocarbons, bacterial loads, nutrients, chlorides as well as suspended sediments.
3. Changes to the hydrologic regime, as well as water quality, affect the ecological condition and function of wetlands in urbanizing areas leading to measurable biological responses. Wetland flora and fauna communities are dependent on the wetland‘s hydroperiod. Changes to the hydrologic regime resulted in reduced species richness and the loss of sensitive species. Water quality changes resulted in shifts in vegetation community and a concern regarding the bioaccumulation of toxins. However, it is not just one type of impact that accounts for the biological effects in wetlands, but the compounding effects of all impacts.
This review examines two case studies of wetlands that were monitored during the development process to assess change. These case studies highlight problems with data collection and analysis pre- and post-development. Gaps in knowledge are identified through both these case studies and the literature. Recommendations for future work, both research and guideline/protocol development are outlined.