ASSESSMENT OF IMPACTS OF CLIMATE CHANGE ON WATER QUALITY IN THE SOUTHEASTERN UNITED STATES¹

Abstract

An assessment of current and future water quality conditions in the southeastern United States has been conducted using the EPA BASINS GIS/database system. The analysis has been conducted for dissolved oxygen, total nitrate nitrogen and pH. Future streamflow conditions have been predicted for the region based on the United Kingdom Hadley Center climate model. Thus far, the analyses have been conducted at a fairly coarse spatial scale due to time and resource limitations. Two hydrologic modeling techniques have been employed in future streamflow prediction: a regional stochastic approach and the application of a physically based soil moisture model. The regional model has been applied to the entire area while the physically based model is being used at selected locations to enhance and support the stochastic model. The results of the study reveal that few basins in the southeast exhibit dissolved oxygen problems, but that several watersheds exhibit high nitrogen levels. These basins are located in regions of intense agricultural activity or in proximity to the gulf coast. In many of these areas, streamflow is projected to decline over the next 30–50 years, thus exacerbating these water quality problems.

Statistical analyses on the effects of air temperature fluctuations on river water qualities

“…Recently, a considerable number of studies have focused on various natural and socioeconomic effects of global warming. These changes are considered to cause disruptions, especially on aquatic ecosystems, such as the deterioration of river water quality, eutrophication of lakes and coastal zones, and so forth (Avila et al, 1996;Sumi et al, 1996;Magnuson et al, 1997;Schindler, 1997;Pilgrim et al, 1998;Cruise et al, 1999;Fukushima et al, 2000;Ozaki et al, 1999Ozaki et al, , 2001. Numerical simulations of river water quality have been conducted using hydrological models, and common tendencies can be found regarding the influence of air temperature and precipitation changes (Hanaki et al, 1998).…”

Potential impacts of climate change on groundwater recharge and streamflow in a central European low mountain range

“…SWAT was developed to assess the impacts of land use changes on water supplies, erosion and nonpoint source pollution in meso-to macroscale catchments. The model includes approaches describing how CO 2 concentration, precipitation, temperature and humidity affect plant growth, evapotranspiration, snow and runoff generation, and therefore is also used to investigate climate change effects (Fontaine et al, 2001;Stonefelt et al, 2000;Cruise et al, 1999;Rosenberg et al, 1999;Hanratty and Stefan, 1998).…”

Comparative physiological, biochemical, and molecular thermal stress response profiles for two Unionid freshwater mussel species

“…These declines most likely result from a combination of physical habitat modification, point source pollution, sedimentation, invasive species, and warming temperatures due to climate change (as reviewed by Hastie et al, 2003). Warming trends have already caused alterations in thermal structure and water quality (Cruise et al, 2000; reviewed by Caissie, 2006), resulting in downstream effects on primary producers, migratory fishes and macroinvertebrates (Davis et al, 2013;Harper and Peckarsky, 2006;MacFadyen et al, 2004;O'Reilly et al, 2003;Winder et al, 2009). Ecosystem-level functional alteration may be especially pronounced within the state of Alabama, a renowned biodiversity hotspot for freshwater fauna, particularly fishes, crayfish and mollusks (Lydeard and Mayden, 1995).…”