The effect of climate and land use change on flow duration in the Maryland Piedmont region

Abstract

Abstract:This paper describes the use of a continuous streamflow model to examine the effects of climate and land use change on flow duration in six urbanizing watersheds in the Maryland Piedmont region. The hydrologic model is coupled with an optimization routine to achieve an agreement between observed and simulated streamflow. Future predictions are made for three scenarios: future climate change, land use change, and jointly varying climate and land use. Future climate is modelled using precipitation and temperature predictions for the Canadian Climate Centre (CCC) and Hadley climate models. Results show that a significant increase in temperature under the CCC climate predictions produces a decreasing trend in low flows. A significant increasing trend in precipitation under the Hadley climate predictions produces an increasing trend in peak flows. Land use change by itself, as simulated by an additional 10% increase in imperviousness (from 20Ð5 to 30Ð5%), produces no significant changes in the simulated flow durations. However, coupling the effects of land use change with climate change leads to more significant decreasing trends in low flows under the CCC climate predictions and more significant increasing trends in peak flows under Hadley climate predictions than when climate change alone is employed. These findings indicate that combined land use and climate change can result in more significant hydrologic change than either driver acting alone.

Modelling the hydrologic response of a mesoscale Andean watershed to changes in land use patterns for environmental planning

“…In general, forestry plantations tend to reduce mean annual discharge, whereas agriculture increases it. These results are in agreement with those obtained by (Hejazi and Moglen, 2008) for a watershed located in Thailand. Thus, implementation of protection laws for native species conservation and regulated land use change are strongly recommended in order to preserve the water resources of the watershed.…”

“…Klöcking and Hamberlandt (2002) stated that land use changes affect the hydrologic response of large watershed at the subbasin scale, and thus the interaction between the different subbasins plays a key role in the behaviour of the watershed. Even when the hydrologic response of small watersheds (< 10 km 2 ) has been extensively documented in previous studies (Bosch and Hewlett, 1982;Sahin and Hall, 1996;Stednick, 1996;Brown et al, 2005), and the response to land use changes of large scale basins have been documented for the Northern Hemisphere (Thanapakpawin et al, 2007;Hejazi and Moglen, 2008;Breuer and Huisman, 2009;van Roosmalen et al, 2009) a lack of studies on the response of mesoscale basins located in the Southern Hemisphere is detected (Costa et al, 2003;Croke et al, 2004).…”

Effects of changes in land use and climate on water availability of a tropical catchment

“…higher precipitation intensity) rather than land use. Thus, combination of land use change and climate change might result in more significant hydrological changes than either driver acting alone (Hejazi & Moglen, 2008). A more thorough study, however, need to be done in the future focusing on the role of climate change (e.g.…”

“…A projected increase in precipitation accompanied by the deforestation scenario (BAU scenario) will have more significant impacts on streamflow and surface runoff than land use change or climate change acting alone (Legesse et al, 2003;Hejazi & Moglen, 2008;Khoi & Suetsugi, 2014). Moreover, at a monthly scale, the streamflow originating from surface runoff significantly increases during the wet season and decreases during the dry season, indicating that more extreme events (i.e.…”

“…Blöschl et al (2007) argue that climate change impacts on water availability vary depending on the spatial scale, due to direct and indirect influences through feedback mechanisms between land use and climate changes. Hejazi & Moglen (2008) found that the combination of land use change and climate change might result in more significant hydrological changes than either driver acting alone.…”