摘要

The Matahara Sugar Estate (MSE), after nearly 60years of irrigation, is experiencing the effects of waterlogging and salinization in some fields. The problem is believed to be the result of the expansion of (saline and alkaline) Lake Basaka towards the plantation fields. The objective of this study was to determine the geometry of the lake (area and shape) in roughly the past half- century (1957-2015) from both Landsat images and local information and then assess its negative effects on MSE's soil and water quality. Monthly groundwater (GW) depth was monitored using piezometer tubes. Water and soil samples were collected from each of the piezometer locations and analysed for important physico-chemical parameters. The results indicate that the lake expanded approximately 47.3km(2) in the past half-century. The soil quality was found to be very poor in plantation sections with very shallow GW depth and severe salinity conditions. The lake, as revealed by the results, is intruding into the groundwater system of MSE on the Abadir side. Assuming continuation of the past trends, the lake is expected to inundate parts of MSE in the next few years and, hence, challenge the production and productivity of MSE significantly. The lake has the potential to join the Awash River, thereby impacting all downstream irrigation developments in the basin and the livelihood of the people depending on the water resources. As the area is situated in the uppermost part of Main Ethiopian Rift Valley, other factors are expected to exacerbate its expansion even in the future. Overall, the study results present the potential damage caused by the lake to MSE and provides valuable information for the reclamation measures to be taken for the sustainability of MSE.

  • 出版日期2017-7