Potential Impact of Climate Change on Suspended Sediment Yield in NW Spain: A Case Study on the Corbeira Catchment

Abstract

Soil losses and the subsequent sediment delivery constitute significant environmental threats. Climate change is likely to have an impact on the availability of water and therefore on sediment yield in catchments. In this context, quantifying the sediment response to an increased atmospheric CO 2 concentration and climate change is of utmost importance to the proper management of rural catchments. However, quantitative assessment of climate change impact remains a complex task. In this study, the potential medium (2031-2060) and long-term (2069-2098) impacts of projected changes of temperature, rainfall and CO 2 concentration on sediment yield in a small rural catchment located in NW Spain were evaluated using the Soil and Water Assessment Tool (SWAT) model. Climate change scenarios were created using future climate data projected by regional climate models from the ENSEMBLES project and two CO 2 concentration scenarios (550 and 660 ppm). The results showed that climate change would have a noticeable impact on suspended sediment if the forecast temperature, rainfall and CO 2 concentration changes included in this study were met. Overall, suspended sediment is expected to decrease (2031-2060: −11%, 2069-2098: −8%) compared to the baseline period , mainly due to decreased streamflow. However, an increase in sediment transport in winter is predicted, possibly associated with increased erosion in cultivated areas (11%-17%), suggesting that, at this time of the year, the effect of soil detachment prevails over sediment transport capacity. Consequently, management practices aimed at reducing soil erosion in cultivated areas should be carried out, because these are the main source of sediment in the study area.

The Effect of Climate Change on Loss of Lake Volume: Case of Sedimentation in Central Rift Valley Basin, Ethiopia

“…from climate change has also been reported by many scholars [12,17,26,54,55]. In a similar study, average annual sediment loads generally decreased in response to climate change by 23.5% and 3.3% under RCP4.5 and RCP8.5, respectively in the mid-century (2046-2065) [15].…”

“…It has been revealed in a study conducted by Adem et al [51] in the Upper Gilgel Abay of the Blue Nile Basin in Ethiopia that sediment yield was related to a change in climate variables and thus to streamflow. The variation in the values of sediment yield due to streamflow change that resulted from climate change has also been reported by many scholars [12,17,26,54,55]. In a similar study, average annual sediment loads generally decreased in response to climate change by 23.5% and 3.3% under RCP4.5 and RCP8.5, respectively in the mid-century (2046-2065) [15].…”

“…Li et al [56] predicted the annual rate of decrease in water and sediment discharges mainly controlled by climate variability. Rodríguez-Blanco et al [17] also showed that suspended sediment is generally expected to decrease in 2031-2060 by 11%, and in 2069-2098 by 8%, as compared to the baseline period . This was mainly due to decreased streamflow in response to climate change.…”

Response of Sediment Load to Hydrological Change in the Upstream Part of the Lancang-Mekong River over the Past 50 Years

“…The sediment load correspondingly increased when runoff showed an upward trend. The result demonstrates the conclusion that a majority part of the sediment load can be explained by the maximum discharge and the runoff [10]. Given the better correlations of runoff and PF with sediment load, the operation of dams could play an important role in the sediment load change through (extreme) runoff regulation in the upstream part of the Lancang-Mekong River.…”

“…[5,6]. Considerable research has been conducted on how factors control sediment yield in a basin (e.g., land use change [7], land slopes [8], weather types [9], and precipitation or other climatic variables change [10][11][12][13][14]), the spatial-temporal change of sediment concentration and Runoff-Sediment Relationship (RSR) [15,16], and the scale effect of RSR [17][18][19]. These studies provided important trend data and are useful for understanding sediment rich water energy resources [22,27].…”