R ES E A R C H Open Access
Effect of Eucalyptus expansion on surface
runoff in the central highlands of Ethiopia
, Boniface P. Mbilinyi
, Henry F. Mahoo
and Mulugeta Lemenih
Introduction: Land use/land cover change can affect the ecological processes of an area such as hydrological
cycle. The change in the condition of water resources of an area could be a good indicator of changes in
ecosystem function as a result of altered land use/land cover. Eucalyptus expansion in central Ethiopia is one of the
recent land use/land cover changes causing controversy on its potential ecological effect. This study was designed
to evaluate effects of three adjacent land uses/land covers, i.e. cultivated land, grassland and Eucalyptus woodlot on
surface runoff in Meja River watershed, central Ethiopia.
Methods: The rainfall amount at each study catchment was collected using the rain gauge installed to record daily
rainfall amount. The three land use/land cover types in each study catchment were selected for comparison as
treatments. Four replications of each land use/land cover were used forming a total of 12 runoff plots. The rainfall
and runoff data were collected twice a day for 91 days.
Results: The study found that land use/land cover significantly affects surface runoff generated from the plots.
Higher runoff was recorded from cultivated land. There was no significant difference on runoff volume between
grassland and Eucalyptus woodlot.
Conclusions: This shows that expansion of Eucalyptus on grassland could not have significant impact on surface
runoff generation but if planted on previously farmland could reduce surface runoff.
Keywords: Cultivated land, Grassland, Runoff plots, Land use, Meja River watershed
Sustainable land management is an important key to the
increasing land productivity, better livelihoods and im-
proved ecosystem health (Liniger et al. 2011). Factors
that lead to land degradation are population pressure,
overgrazing, deforestation, crop cultivation expansion on
steep slope and severe soil loss in Ethiopia (Bishaw 2001;
Taddese 2001; Tamene and Vlek 2008; Hurni et al. 2010;
Gashaw et al. 2014). Land management is about explor-
ing existing and possible land use/land cover (LULC)
and making decision on choosing to implement the one
that ensure sustainable production (UNEP 2014). Such
decisions could directly affect ecosystem functions and
services and alter condition of ecosystem resources such
as soil, water, flora and fauna (Lemenih 2004; Maitima et
al. 2009). Decision makers, therefore, need to carefully
weigh the trade-off between increasing productivity on
the one hand and loss of other ecosystem functions and
services on the other.
In Ethiopia, land degradation had begun with the
emergence of cultivation thousand years ago (Hurni
1990; Yirdaw 1996). Ethiopia is recognized for its land
resource degradation, food insecurity, which has defor-
estation and forest degradation as its root causes
(Bishaw 2001; Hurni 1990; Tamene and Vlek 2008).
Various studies have shown changes in LULC, with most
of the changes being the expansion of cultivated land,
the increment of bare land, decline in forest areas and
reduction in grazing land (Dwivedi et al. 2005; Haile et
al. 2010; Kidane et al. 2012). The expansion of Eucalyp-
tus woodlots and plantation are also observed in the
highlands of Ethiopia (Jenbere et al. 2012; Chanie et al.
2013; Jaleta et al. 2016a). These dynamics in LULC have
direct and indirect impact on soil and water resources of
* Correspondence: firstname.lastname@example.org
Department of Engineering Sciences and Technology, Sokoine University of
Agriculture, P.O.Box 3003, Morogoro, Tanzania
Full list of author information is available at the end of the article
© The Author(s). 2017 Open Access This article is distributed under the terms of the Creative Commons Attribution 4.0
International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and
reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to
the Creative Commons license, and indicate if changes were made.
Jaleta et al. Ecological Processes (2017) 6:1