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WOLAITA SODO UNIVERSITY
GRADUATE STUDYS DIRECTORATE
REVIEW ON: EFFECT OF SOIL AND WATER CONSERVATION PRACTICES ON
SOIL LOSS AND NUTRIENT LOSS IN ETHIOPIA
BY: AMANAWIT KASANEH
ADVISOR: FANUEL LAEKEMARIAM (PhD, ASSOCIATED PROFESSOR)
JULY, 2022
WOLAITA SODO, ETHIOPIA

OUTLINES
INTRODUCTION
OBJECTIVE
LITRATURE
CONCLUSION

INTRODUCTION
The majority of the population of Ethiopia consists of
farmers dependent on agricultural products.
The conservation of soil and water resources is a key
aspect of the economic and environmental
Sustainability of all types of agricultural and forestry
systems.

Cont..
Soil and water conservation practices and agricultural
activities can change the soil surface morphology and thus
affect erosion and nutrient losses.
The loss of soil nutrients in Ethiopia is related to cultural
practices such as, deforestation, overgrazing, removal of
vegetative cover and burning plant residues.
Therefore, the objective this study is to review the Effect
of soil and water conservation practices on soil loss and
nutrient loss in Ethiopia.

LITERATURE REVIEW
 Soil and water conservation practice in Ethiopia
 In Ethiopia (SWC) Practice have been carried out at individual
or community levels.
 Soil and water conservation practices is help to minimize
erosion, improve fertility and soil structures.
Most common soil and water conservation practices are,
 Agronomic or Biological
 Physical or mechanical

 Agronomic or Biological Soil and Water
Conservation Practices
According to FAO (1984), agronomic measures is that
vegetation is used, either alive or dead, in that protects
the soil surface from;
 the direct impact of raindrops and to create a rough surface
which will physically impede run-off and
 slow it down to non-erosive velocities.

Some examples of agronomic measures
Crop rotation: Crop rotation is the practice of growing
different types of crops in succession on the same field
to get maximum profit.
Mono cropping results in exhaustion of soil nutrients
and depletes soil fertility (Anita et al., 2020).
Source: Amisalu, 2018

Cont..
Mulching: is the covering of the soil with crop
residues such as straw, maize stalks, palm fronds or
standing stubble (Morgan, 2005; MoA, 2016 ).
The cover protects the soil from the hot sun and from
the impact of raindrops, minimizing soil crusting,
erosion and runoff.
source;:WOCAT, www.wocat.net

Cont..
 Intercropping: As the name indicating Intercropping
is the cultivation of two or more crops at the same time
in the same field.
Source: ( Susan V. Fisk, 2017) Source: (Allsela, 2018)

Cont..
Fallowing: Fallowing refers to the process of
leaving the agricultural land without planting any
corps for some time to improve it’s soil fertility
(Mishra et al., 2018).
(Yin and Radeloff, 2018)

Cont..
 Mechanical/Physical soil and water
conservation practices
Mechanical practices are used to prevent or control the
movement of water on the surface of the soil.
Mechanical measures or engineering structures are
designed to modify the land slope, to convey runoff
water safely, to the waterways, to reduce sedimentation
and runoff velocity, and to improve water quality.

Cont..
Some examples of Mechanical SWC Practices
Terracing: Terracing could be one way of stopping or
reducing the degrading effect of soil erosion and saving
soil and water.
Terraces are created to intercept surface runoff, improve
water infiltration, and reduce evaporation.

Cont..
Check dam: Check dam is an obstruction wall across the
bottom of a gully or a small river to reduce the velocity of
the runoff.

Cont..
 Fanya juu: Fanya juu terraces are constructed by digging
ditches and heaping the soil forming bunds in the upper
sides of the ditches.

Cont..
Effects of Soil and Water Conservation
Practices
 Effects on degraded land rehabilitation
Land rehabilitation is an intervention designed to make
a geo-ecological improvement.
It is involves the mitigation or reversal of land
degradation caused by poor land husbandry practices,
especially agricultural practices.

Cont..
 Effects on selected physical properties of soil
The physical properties of soils determine their
adaptability to cultivation and that can be supported
by the soil.
Soil physical properties on affects of SWC practices,
texture, structure, density, porosity, consistence,
temperature, and color.

Cont..
The soil physical properties change with changes in land use
system and its management practices such as,
Intensity of cultivation, the instrument used, and the nature
of the land under cultivation.
Mulugeta Demelash and Karl (2010), confirmed that soils
of non-conserved land had the highest percentage of mean
value of clay and silt.
And the lowest percentage of sand due to the exposure of
soil by tillage to soil erosion by water that ultimately
exposes the subsoil, which is naturally high in clay content.

Cont..
 Effects on Soil nutrient loss and moisture
SWC practices are essential to enhance available soil
phosphorus, soil potassium and soil nitrogen and
reduce soil loss.
maintaining optimum soil moisture content is a
prerequisite for proper aeration, nutrient
transformations, and availability, biological activity
and finally higher crop yields.

Cont..
Various studies have conducted on the effect of soil and water
conservation measures on soil loss in Ethiopia highlands
(Admassu et al. 2014; Abrha et al., 2018; Grum et al., 2017).
For instance, Admassu et al. (2014), observed that zero/minimum
tillage with 2 t ha−1 yr−1 crop residue was reduced soil loss by
47% compared to control treatment in the Humid Highlands of
Ethiopia.
Grum, et al. (2017). also reported tied ridges with straw mulch
reduced soil loss by 91 % compared to non-conserved land Gule
sub-watershed.
In addition ( Abrha et al., 2018 ). observed that stone-faced soil
bund reduced soil loss by 90% compared with untreated
cultivated field.

Cont..
Soil property Conserved Non conserved Reference
pH 5.77 5.66 Osman, (2013)
Soil OM 4.3% 2.83% Mengistu et al.
(2016)
TN 0.27% 0.138% Landon, (2013)
CEC 33.6 cmol/kg 13.9 cmol/ kg Landon, (2013)
Effect of SWC practices on nutrient loss.

Cont..
Management
practices
Soil Loss (tone/ha) Reference
Treated Untreated
Fanya Juu 35.6 110.1 Mengistu et al.,
(2015)
Stone Bund 23 119 Selassie and
Belay (2013)
Soil bund 46 71.3 Tadele et al.,
(2014)
Trench 4 39 Taye et al.,
(2013)
Minimum
tillage with
crop resudes
16 30 Admassu et al.,
(2019)
Effect of SWC practices on soil loss

Cont..
 Effects on slope gradient change
 One of the functions of constructing SWC measures is reducing
the slope gradient of the landscape features.
 Slope gradient as a topography factor also plays an important
role on impacting soil erosion intensity.
 Gebremichael et al., (2005), observed that sediment accumulated
on stone bunds changed the inter slope gradient from 14.1% to
11.2%.
 Amdemariam, et al. [26] also observed that a soil bund had the
lowest inter-terrace slope (12%) while in the control treatment
the inter slope was characterized as high (21%).

CONCLUSION
It is concluded that SWC practices on soil loss and
nutrient loss have positive impacts on soil fertility and
crop productivity of cultivated lands.
Conservation of soil and water resources is important
for sustainability of agriculture and environment.
Various studies have conducted on the effect of soil
and water conservation measures on soil loss in
Ethiopia.

Cont..
Biological or agronomic measures refer to farming
practices, which help to minimize erosion, improve fertility
and soil structures.
Mechanical or engineering are designed to modify the land
slope, to reduce sedimentation and runoff velocity, and to
improve water quality.

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