Quantification of the Impact of Integrated Soil and Water Conservation Measures on Groundwater Availability in Mendae Catchment, Abraha We-Atsebaha, eastern Tigray, Ethiopia

Abstract

The paper tries to evaluate the impact of integrated soil and water conservation measures on water availability in Mendae catchment (10.37 km 2 ), which is located in the northeastern Tigray. Historical background of the catchment with respect to its land use was obtained from the local Bureau of Agriculture and Rural Development office. The hydrology of the area was characterized based on its land use, soil, slope, rainfall, temperature, evapotranspiration, and runoff. Thornthwaite method and Thornthwaite soil-water balance model were used to determine potential and actual evapotranspiration, respectively. The mean annual runoff from the catchment was computed using runoff coefficient method. Before the intervention, the area was severely degraded and known with scarcity of water. Integrated soil and water conservation (physical and biological measures) was introduced to the area since 1993. The catchment is characterized by two rainy season and three dry seasons during the year. The rainy seasons in total have four months whereas the dry seasons comprises of eight months. The mean annual rainfall of the catchment is 565.8 mm, out of which rainy season accounts for 86.13% and the dry season for 13.87%. The rain that occurs with a very high concentration accounts 73.20 % of the mean annual rainfall of the catchment and this occur only in two months (July and August).The mean annual potential and actual evapotranspiration was found to be 832.67 mm and 405.61mm, respectively. The volume of runoff before and after the intervention was found to be 26.88 % and 17.19 % of the mean annual rainfall of the catchment, respectively. The groundwater recharge before and after the intervention was found to be 1.43 % and 19.04% of the mean annual rainfall of the catchment, respectively. The availability of groundwater has increased more than 10 times since 1993. Though the groundwater is being used for both complimentary and supplementary irrigation during the dry and rainy season, respectively, construction of additional physical conservation structures is suggested to further improve the groundwater availability in the area.

Change in low flows due to catchment management dynamics—Application of a comparative modelling approach

“…However, these studies were focused either at experimental plot level (e.g. Alemayehu et al, ; Descheemaeker et al, ; Negusse et al, ; Nyssen et al, ) or on very small watersheds and survey studies (Belay et al, , Gebremeskel et al, , Woldearegay et al, 2018), from which it is problematic to extrapolate and infer basin‐wide implications of SWC interventions. This study uniquely integrate statistical tools (MK and Pettitt) to investigate the pattern of streamflow before and after implementations of SWC activities, indicators of hydrological alterations to identify fluctuations of hydrological parameters due to the interventions and finally hydrological simulations to understand the difference in the hydrological processes of a comparative catchments that have different level of SWC interventions.…”

Multifunctional Land Uses in Africa

“…The integrated watershed management raised groundwater levels by up to five metres (Gebregziabher et al 2016;Negusse et al 2013). After the intervention, water was found at three metres' depth compared to eight, before.…”

Conservation and production impacts of soil and water conservation practices under different socio-economic and biophysical setting: a review

“…In experimental plot, Gebeyehu et al (2013) reported that after each storm, runoff pounded behind SWC structures, leading to rapidly vegetation recover at the onset of the rainy season, forming patchy vegetation islands around SWC structures while all of the runoff from control plots ended up in the collector trenches. The reduction in runoff and soil loss have several beneficial effects: increased soil moisture content (Mesfin 2004 andMihrete 2014); groundwater recharge (ICRISAT, 2007;Negusse et al, 2013) soil-loss reduction (Herweg and Ludi, 1999;Gebremichael et al, 2005;Gebeyehu et al, 2013); increased in situ sediment deposition, making the hill slope suitable for agriculture due to progressive terrace development (Haregeweyn et al, 2006;Nyssen et al, 2007), and reduced siltation of natural and artificial reservoirs (Haregeweyn et al, 2006;Tamene et al, 2005 andEmiru, 2009). The role of SWC for climate change adaptation and mitigation was also widely reported (Smith et al, 2008;Lal, 2004).…”