An overview of the likely impacts of climate change on water quality of estuaries: ecohydrological adaptive perspectives

KOPPRIO, G. A.; BIANCALANA, F.; FRICKE, A.; GARZÓN CARDONA, J. E. ; LARA, R. J.

Punta del Este

Congreso; XV Congreso latinoamericano de Ciencias del Mar COLACMAR 2013.; 2013

Facultad de Ciencias, Universidad de la República

Estuarine systems are vulnerable to climate driven-changes and anthropogenic impacts. There is currently ample evidence of the effects of recent climate change from polar to tropical ecosystems. Higher recurrence and severity of natural disasters such as floods, droughts, coastal storms, monsoons and hurricanes are expected under scenarios of future greenhouse gas emissions. Warmer temperature and hydrological changes will alter stratification, residence time, oxygen content, salinity, pollutant distribution, phytoplankton growth and nutrient dynamic of estuaries. Harmful algal blooms and water-borne diseases are very likely to be more frequent and expand their distribution. Although considerable research has focused on climate change impacts, to date relatively little work have been conducted on adaptive strategies. Ecohydrology is an integrative low-cost strategy to manage basins threatened by climate change and is based on the use of ecosystem properties to cope with stressors. A good water quality is essential to enhance estuarine ecological resilience. Baseline data is needed to understand the biogeochemical and hydrological processes in a particular estuary. Generally, the preservation, restoration and creation of saltmarshes or mangroves will help to protect the coast from the erosion, increase sediment accretion rates, and improve water quality removing the excess of nutrients and pollutants. Wetlands decrease runoff during floods and increase water retention during droughts. Reservoirs, flooding plains and channels help to damp climate-driven hydrological uncertainty. Harmful algal blooms could be mitigated by the reduction of nutrients and water pulse release. The capacity of hydrologic basins ecosystems to absorb human and natural impacts can be improved through holistic management, which should considered social vulnerability in complex human-natural systems. The building of social-ecological resilience represents a powerful tool of adaptation to climate change.