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Rhodes University
Department of Environmental Science
Land degradation Assessment Using LFA Method in Kopoch, West
Pokot District; Kenya
Author: John Kapoi Kipterer
Submitted to Dr. J Gambiza (PhD)
Submission date: 11/11/2011Submission Time: 11.18 am (East African Time)
Assignment for the partial fulfillment of Certificate in Land degradation Assessment
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Land degradation Assessment Using LFA Method in Kopoch,site, West Pokot
District;Kenya
Abstract
The study focuses on the Land function analysis in land degradation assessment, a simple methodology that utilizes
locally available tools to bring results. The investigators aimed at using this methodology to determine the key
determinants of land functional analysis and to find out the level of degradation in the study area. The study was
conducted and the findings using the methodology concurred with the actual general ground situation in the area.
1.0 Introduction
Land is a non renewable resource on the human timescale.(P.Brabant, 2008).Land is the world’s
most precious resource, it is not however appreciated for its true value because of the high prices
obtained from gold, petroleum, mineral ore and other precious stones, therefore land is treated as
a mere dirt (Edouard Saouma, FAO, 1996)
Land degradation is serious and slow onset disasters that at long run undermines the land
production and change the livelihood patterns. IGAD (Intergovernmental Authority on
Development) economic block of Africa, in the Africa monitoring of Environment for
sustainable development adopted the FAO definition of land degradation for the project.
According to IGAD, (FAO, 2010), Land degradation is the temporary or permanent productive
capacity of land to provide ecosystem goods and services.
A researcher at IRD (P.Brabant, 2008) puts it that land degradation is a process that diminishes
or destroys the agricultural crop or livestock and forest production capacity of land and it i
largely induced by human activities or can be natural phenomenon aggravated by human
activities. From Pierre Brabant studies in West Africa, he found out that, degradation could have
several impacts on soil functions thus deteriorating the productive capacity of land.
1.1 Statement of the Problem
Land degradation has affected land productivity levels and has caused receding pasture in agro
pastoral, pastoral and mixed livelihood zones where livestock keeping forms a major source of
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income or livelihoods in Africa. This undermined the economies (Gambiza, 2010).According to
UNEP 2008, and Taimi, 2008, and FAO, 2005, an estimate of 65% of Africa’s Agricultural land
is degraded due to erosion and both chemical and physical damage, and about 31% of continents
pasture land and 19% of forests and woodland are classified as degraded.
Globally, Land degradation is increasing in severity and extend in many parts of the world with
more that 20% of all cultivated areas, 30% of all forests and 10%garssland are undergoing
degradation (Bai et al, 2008).
It is for this reasons that, studies and integration of assessment methodologies to bring more
understanding on the concept and the threats posed by land degradation to the economy to
inform the stakeholders in land resource management and the users is necessary to control or
mitigate against the impending impacts of land degradation.
1.2 Objectives
To determine the spatial extent and severity of land degradation at large scale using integration
of geospatial technologies and conduct specific plot scale assessment using landscape function
Analysis (LFA)
1.3 Research Questions
What is the correct state of landscape function and extent of degradation at the site?
What are the Key determinants of Landscape function analysis?
1.4 Land degradation definitions in Ostrom framework Considerations
According to Ostrom’ framework, which lays more emphasis on socio economic and political,
set up.
Group one of the students who participated in land degradation course in Rhodes University
(John Kapoi: Kenya, Leigh-Ann de Wet: RSA, Zanele Linda: RSA), September, 2011, defines
land degradation as the process in which natural resource is depleted by human and natural
activities, that ends up affecting the production system, and the capacity of the land, leading to
accelerated degradation.
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The group further identified soil as a resource unit, economic value, agriculture and productivity
as a resource system, Government departments, regional authorities and economic blocks as
governance system natural habitat, vegetation, water and river system as related systems and the
users as the community, farmers and various industries around.
1.5.0 Forms of land degradation
Land degradation manifests itself through vegetation which may provide fuel and fodder
becomes increasing scarce, water courses dry up, thorny weeds predominate in once rich pasture
foot paths disappear into gullies soil becomes thin and stony (Michael Stocking, et al ,2000).
1.5.1 Ecological or Biological land degradation.
The ecological or biological land degradation is where the original plant species and animal
species invade a particular area or locality while the original species (flora and fauna) slowly
disappear or are suppressed. (P.Brabant, 2010). From his research in Africa, Brabant observes
that, Biological degradation is however and indication of reduction in organic matter, macro
fauna quantity and biodiversity.
1.5.2 Chemical Degradation
This is degradation where the soil is polluted causing loss of nutrients, excess salinization,
acidification and alkalization (Brabant, 2010)
1.5.3 Wind and Water Erosion.
Wind and Water erosion is the most common form of land degradation in the IGAD economic
region of Africa. It is for this reason that EU and AU through AMESD project committed 1.94
Million Euros for the assessment to identify extent and severity of land degradation at the
regional and national levels and to identify local hotspots for comprehensive assessment. Wind
erosion severity is common in Northern parts of Africa; however the severity by water erosion in
the IGAD block is more prominent with large economic impacts in food security and livelihoods.
1.5.4 Other forms of land degradation:
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The degradation due to war or conflicts, leaves the land with remnants of explosives,
antipersonnel mines, deformation due to bombings and defoliant sprays and remnants of uranium
munitions. (P.Brabant, 2010)
1.5.4 Causes of land degradation
According to Peter Ikemefuna,et al (2008),The researcher puts it that, Scientists and
development practitioners acknowledge that the worst potent source of land degradation is from
the anthropogenic activities that accelerate changes in land use and land cover through
unsustainable land use. S.Vetter (2005) observes that, the high human and livestock densities and
continuous grazing has led to undesirable vegetation changes and more worrying accelerated the
soil erosion. In my view based on these observations, it is clear that, the socio economic
dynamics coupled with pressure to sustain the economic demands from the populations and poor
planning among the farmers in developing countries at long run leads to land degradation.
S. Vetter (2005) observed that the sedentarization of pastoralist and or supplementary feeding
among the livestock farmers leads to heavy utilization of parts of the range.
A number of causes have been explored by many researchers and professional groups based on
their areas of study. The climatic changes that’s resulted to frequent droughts and heavy
precipitation is one of the main cause of land degradation mainly the wind and water erosion
forms of degradation.
The rapid urbanization as a result of rural urban migration pushing housing demand in urban
areas high, leading to massive clearance of land for development contributes to land degradation
because in the process clearance of once protected and encroachment of forests or undisturbed
areas for construction takes place.
The poor farming methods or practices among the farmers in rural areas, contributes to this
menace. The high population growth in agricultural areas, may compromise the situation further
The poverty among the farmers in rural agricultural areas, and the lack of investment capacity,
leads to poor farming practices hence degradation. (P.Brabant, 2010)
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Land tenure system in some rural areas especially communal land, suffers from degradation
because of poor land management in this systems. The overgrazing and trampling of livestock
leaves this type of land degraded. This case was observed in Mgwalana communal land in
Peddie, in Republic of South Africa, and several pastoral regions of Kenya, Uganda and Ethiopia
under Africa Monitoring of Environment for Sustainable Environment (AMESD) Land
degradation index mapping service. The same observation was made in East Africa by S.Vetter,
2005 where overgrazing was identified as a problem in communal land tenure system areas
Overstocking and overgrazing which leads to removal of vegetation cover that protects soil from
forms of erosion, leads to land degradation. According to S. Vetter, 2005, the susceptibility of
soils to grazers’ induced changes such crusting, compaction and accelerated erosion is related to
texture, with sandy soil being more resilient than clay soil in arid areas.
The armed conflicts, insecurity and rural population movement is one of the cause of land
degradation in war torn countries (P.Brabant, 2010)
HIV and AIDS pandemic. The population suffering from this pandemic, most often do not
engage in there daily duties as opposed to the healthy population’s population energies are
weakened by the effects of this disease and for farmers, the farms are left unattended, and
managed and as a result, soil may be washed away by erosive rainfall, Peter Ikemefuna et al,
2008 observes that, HIV and AIDS Pandemic have significantly compounded the problem of
non-management of land and hence are degraded through service loss of mature population and
loss of farm labor and agricultural knowledge (Peter Ikemefuna, et al 2008.
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2.0 Material and Methods
2.1 Site description
The Site of investigation lies in west Pokot district of Kenya, at a GPS coordinate point of N:
01o 19’ 50.4’’ E 035o,03’ 27.8’’ at an altitude of 1628m above the mean sea level.
Thorny short acacia bushes with patches of grass and other short woody vegetation characterize
the site. The soil type is a mix of sandy loam and silty loam with high stoniness (gravel)
contents.
The terrain characteristics is sloppy with rough surface nature with its aspect sloping towards
the north western part of the district.
2.2 Materials
The main materials utilized for this assessment in the field are very simple and easily available.
The materials includes; the tape measure, at least 30 to 100 m, GPs to be able to reference the
position for time series monitoring over the same transect, pegs to mark beginning and end of
the transect, a bottle of water for soil slate test, and cryptogram testing,
The timer or watch are used to record beginning and the end of the assessment, the camera,
paper clipboard and the writing pens or pencil for data entry purposes
2.3 Methods
The landscape function assessment (LFA) involves three main steps. In step 1 and 2 involves the
details of transects, identification of landscape profile characterizations to set up the transect
though determination of slope aspect, lithology, soils and vegetation type is determined. Step 2
mainly involves location of transect, planning and identification of patches and inter patches for
assessment.
In step 3 of the methodology, the soil assessment in the query zone, litter, rain splash, perennial
vegetation cover, cryptogram cover, crust brokenness, soil erosion type and severity, deposition
materials, soil surface roughness, surface resistance, slate and texture assessment is undertaken
in detail.
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3.0 Results
3.1 Land surface function
The site of investigation comprised of the patches and inter patches along the transect line, where
the mean length of grass patch taking 0.26, shrubs 0.95, litter 0.5 and weed 0.19.The table below
shows the mean length from the LFA analysis.
Landscape
Zone Mean Zone Length (m) %Bare Soil 0.00 0.0Grass 0.26 56.5Weed 0.19 24.3Shrub 0.95 12.6Litter 0.50 6.6Total 100.0
The proportion coverage in the study site is represented in the graph below. The grass takes the
larger proportion I width cover, which implies its dominance in the area, however, bare soil takes
a larger cover share.
Grass takes the larger proportion implying that the site is covered by grass, which helps in
controlling the surface run off.
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Patches Patch zone Code Width (cm) No MeanGrass GP 586 33 17.8Weed WP 544 19 28.6shrub SP 52 2 26.0Total 1182 54 21.9
From the table above, grass cover dominates the site with a width of 586cm as compared to the
weed patch with width of 544 cm
The table below shows the average number of patches in 10m, patch area index among others
Number of Patches/10m 35.9Total Patch Area 3.7 sq. m.Patch Area Index 0.02Landscape Organisation Index 0.93Average Interpatch Length (m) 0.50 mRange Interpatch length 0.1 to 1.4 m.
The key determinant features in this study are the grass, the shrubs and the weed. The table
below shows the proportions held by each feature in the study area.
Zone code Fetch No Mean Proportion %Bare Soil BS 0 0 0.00 0.00 0.00Grass GP 8.5 33 0.26 0.56 56.48Weed WP 3.65 19 0.19 0.24 24.25Shrub SP 1.9 2 0.95 0.13 12.62Litter L 1 2 0.50 0.07 6.64Total 15.05 56 1.90 1 100
This implies that, the grass patches is dominant in this area and during the dry season, this may
dry up leaving the land bare and vulnerable to surface run off.
3.2 Soil surface assessment
The soil stability under grass patch revealed that the stability is high under it as well as under the
weed patch. The table below shows the analysis in LFA.
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Stability
FeaturesMax score BG GP WP L SP
Soil Cover 5 1 4 4 2ln 1Litter Cover (simple) 10 1 2 3 3 2Cryptogam cover 4 1 1 1 1 3Crust broken-ness 4 2 1 1 2 1Erosion type & severity 4 2 4 3 2 0Deposited materials 4 4 4 4 4 4Surface resist. to disturb. 5 5 5 4 1 1Slake test 4 3 3 2 2 3Total 19 24 22 15 15Divide by 40 40 40 35 36% 47.50 60.00 55.00 42.86 41.67
The infiltration under this assessment was found to be high under the shrub patch and litter, this
allows the water and minerals to infiltrate into the soil under it necessitating growth and
saturation of the soil.
Infiltration/runoff
FeaturesMax score BS GP WP L SP
Per. basal / canopy cover 4 1 4 3 1 3Litter cover, orig & incorp. 30 1 3 5.985 5.985 3Soil surface roughness 5 1 1 4 1 1Slake test 4 3 3 2 2 3Texture 4 3 3 2 2 2Surface resist. to disturb. 10 6.6 6.6 1 10 10Total 15.6 20.6 17.985 21.985 22Divide by 57 57 57 57 57% 27.37 36.14 31.55 38.57 38.60
This implies that, the nutrients cycling are high inn this patches. The table below shows the
nutrient cycling in these patches.
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Nutrient cycling status
FeaturesMax score BS GP WP L SP
Per. basal / canopy cover 4 1 4 3 1 3Litter cover, orig & incorp. 30 1 3 5.985 5.985 3Cryptogam cover 4 1 1 1 1 3Soil surface roughness 5 1 1 4 1 1Total 4 9 13.985 8.985 10Divide by 43 43 43 43 43% 9.3 20.9 32.5 20.9 23.3
4.0 Conclusion
The land under investigation is degraded but the degree of degradation is low.
The key determinant landscape features are bare soil, grass weed, shrubs and litter under the
patches. This features helps in controlling the rate of surface run off in the area, they intercept
the soil mass moved, and control the run off speed.
5.0 Reference
1. Brabant P.2010: A land degradation Assessment and Mapping methods; a standard
guideline proposal
2. D.J Tongway, N.L Hindley, 2005: Landscape Function Analysis: Procedure for
Monitoring and assessing Landscape.
3. D.L Dent and Z.G Bai, 2008: Assessment of land degradation using NASA-GIMMS: A
case study in Kenya.
4. Elinor Ostrom et al, 2009: Ageneral framework for analyzing sustainability of social
ecological systems
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5. Karen Wentzel, 2002: Determination of Overall soil erosion potential in Nsikazi District
(MpumalangaProvince, South Africa) Using Remote Sensing and GIS
6. L.C Stringer and M.S Reed, 2006: Land degradation Assessment in Southern Africa:
Integrating local and scientific knowledge bases.
7. Michael Stocking and Niamh Murnaghan, 2000: Land degradation guidelines for field
Assessment.
8. P.Brabant,S.Darraco, K Egue, V.Simonneuax, 1996: Human Induced land degradation
status map of degraded index rating.
9. Peter Ikemefuna, Ezeakund Alaci, Davidson: Analytical Situation of Land degradation
and Sustainable Management Strategies in Africa
10. R.J Scholes, 2009 Syndrome of dry land degradation in Southern Africa
11. S.Vetter, 2005: Rangeland at equilibrium and Non-equilibrium: Recent development in
the debate.
12. S.Vetter, W.M Goqwana,W.J Bond.W.W Trollope: Effects of Land tenure, geology and
topography on vegetation abd soils of two grassland types in South Africa.
13. Taimi Sofia Kaplanga, 2008: A review of Land degradation Assessment Methods
14. Torrion Jessica. A, 2002: Land degradation detection, Mapping and Monitoring in the
Lake Naivasha Basin, Kenya
15. Vargas R. R.Omuto C. T.Njeru L. 2007: Land degradation Assessment of a selected
study area in Somaliland. The application of LADA-WOCAT Approach FAO-SWALIM,
Project Report L-10, Nairobi, Kenya
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6.0 Appendix
Pictures
Kopoch area Rhodes University
Local Inhabitants of the study site Dr. J. Gambiza and the Participants,Nov, 2011
Kapoi in Kopoch site1, Kenya Kapoch Site 2