Land use and land cover change impact on groundwater recharge: The case of lake haramaya watershed, Ethiopia
Book Chapter
Gebere, SB, Alamirew, T, Merkel, BJ et al. (2015). Land use and land cover change impact on groundwater recharge: The case of lake haramaya watershed, Ethiopia
. 93-110. 10.1007/978-3-319-18787-7_6
Gebere, SB, Alamirew, T, Merkel, BJ et al. (2015). Land use and land cover change impact on groundwater recharge: The case of lake haramaya watershed, Ethiopia
. 93-110. 10.1007/978-3-319-18787-7_6
Anthropogenic actions have been dramatically changing the land cover of the earth with a substantial impact on the soil, water, and atmosphere. Haramaya watershed is located in the eastern part of Ethiopia which encompasses the dry Lake Haramaya, primarily used for agricultural production with burgeoning population, dramatic changes in land use land cover have been observed over the past few decades. The land cover changes have impacted the water balance of the watershed by changing groundwater level. This study focuses on assessing the impact of land use land cover changes on groundwater recharge potential of the watershed. Future land use change was simulated using CLUE-S (Conversion of Land Use and its Effects at Small regional extent) land use change model. The result showed an increase in chat cultivation from 6276 ha in 2011 to 7282 and 7000 ha in 2028 under current conditions (scenario-1) and good watershed management (scenario-2), respectively. Chat (Catha edulis) also referred to as Khat, is a stimulant plant chewed as a tradition but labeled as drug by the World Health Organization (WHO). Cultivated land declined from 4975 ha in 2011 to 3999 and 4013 ha in 2028 under both scenarios 1 and 2, respectively. The simulated result of the WetSpass water balance model showed that the groundwater recharge in the watershed is strongly influenced by land use land cover change. The annual groundwater recharge in the year 2011 ranged from 0 to 90 mm. A land use land cover projection to 2028 with baseline and good management scenarios showed the range of recharge values decreased to 0-83 and 0-87 mm, respectively. At the same time, groundwater level will continue declining due to increased abstraction. Therefore, it is recommended that the concerned authorities should consider the impact of land use change on the water resources of the watershed in order to optimally utilize the available water resources and to find alternative water sources to fill the deficit resulting from groundwater table decline.
