Sugarcane growing in the river bed

Riverbed reclamation & silt trapping for sugarcane (Kenya)

Kyanda (Kikamab)

Description

Silt harvesting on riverbeds to maximise sugarcane growing in semi arid area

The technology first involves fencing off part of a riverbed with cut thorn scrub in order to keep livestock away. The enclosed area is then mulched with brushwood and herbaceous materials in places. Sugar cane is planted and harvested piecemeal when mature. Kamuti plants a perennial grass (Cynodon dactylon) between the canes to help bind the sand. This exercise has been done, incrementally, over a series of seasons, enclosing an increasingly large area. When the rains return and the river flows, floodwater passes through and over the sugar cane and silt is deposited as the flow is slowed.

Purpose of the Technology: This initiative is categorized as an agronomic/vegetative measure, for reclamation of land. Its purpose is to increase water stored in the soil and to increase fertility by sediment harvesting, as a way of making land productive, while simultaneously addressing riverbed erosion. Farm income increase from the sale of sugar cane is the main production/ socio-economic benefit, while the ecological benefits include sediment accumulation, soil (ie riverbed and bank) loss reduction, soil cover improvement, increase in soil moisture and increase in soil fertility.

Establishment / maintenance activities and inputs: The action involves cutting tree branches, trimming pegs about 1m long, and hammering these pegs into the bed of the sand river, parallel to the bank, enclosing a long narrow strip. This initial strip may be 10 metres wide in a riverbed of 100 meters wide. The tree branches and trimmings are used to form a brushwood-netting barrier, which protects the area from livestock, and simultaneously slows the river flow and traps sediments. To further strengthen the barrier, star grass (Cynodon dactylon) is planted along the line of the fence. Inside the fenced-off area, sugar cane cuttings are buried at a depth of 0.4 m, and the same grass planted between the canes. The area is mulched with brushwood, which rots down to increase organic matter in the soil. These cuttings sprout and an intercrop of grass and sugar cane is the result. Maintenance comprises repairing the fence and cutting grass for mulching. No special tools are required. To be effective, the technology requires mulching every season, as the old mulch is covered by the silt load during the rainy period. The perimeter fence is maintained seasonally and requires considerable material. Occasionally when the rainfall is heavy, the sugar cane is swept away by floods and needs replacing.

Natural / human environment: The farm on which this technology is applied is in the arid far-north of Mwingi District. During the rainy season the farm can be inaccessible. The farmer, who is over 60 years of age, lives with his wives and children in what effectively forms a mini-village. The annual average rainfall in this area is barely 500 mm, and famine years are common. Temperatures are consistently high. The farm borders a dry sand riverbed.

Location

Location: Eastern Province, Kenya

No. of Technology sites analysed:

Geo-reference of selected sites
  • 38.0163, -0.2979

Spread of the Technology: evenly spread over an area (0.01 km²)

In a permanently protected area?:

Date of implementation: more than 50 years ago (traditional)

Type of introduction

Classification of the Technology

Main purpose
  • improve production
  • reduce, prevent, restore land degradation
  • conserve ecosystem
  • protect a watershed/ downstream areas – in combination with other Technologies
  • preserve/ improve biodiversity
  • reduce risk of disasters
  • adapt to climate change/ extremes and its impacts
  • mitigate climate change and its impacts
  • create beneficial economic impact
  • create beneficial social impact
Land use

  • Cropland
    • Perennial (non-woody) cropping: sugar cane, star grass (Cynodon dactylon)
    Number of growing seasons per year: 2
Water supply
  • rainfed
  • mixed rainfed-irrigated
  • full irrigation

Purpose related to land degradation
  • prevent land degradation
  • reduce land degradation
  • restore/ rehabilitate severely degraded land
  • adapt to land degradation
  • not applicable
Degradation addressed
  • soil erosion by water - Wg: gully erosion/ gullying
  • chemical soil deterioration - Cn: fertility decline and reduced organic matter content (not caused by erosion)
SLM group
  • minimal soil disturbance
  • water harvesting
SLM measures
  • agronomic measures - A7: Others
  • vegetative measures - V2: Grasses and perennial herbaceous plants
  • structural measures - S6: Walls, barriers, palisades, fences
  • management measures - M1: Change of land use type

Technical drawing

Technical specifications
Reclaiming part of sand river bed with Sugar cane

Kenya

Technical knowledge required for field staff / advisors: moderate

Technical knowledge required for land users: high

Main technical functions: increase / maintain water stored in soil

Secondary technical functions: sediment retention / trapping, sediment harvesting, increase in soil fertility

Mulching
Material/ species: grasses
Quantity/ density: 2
Remarks: grass scattered

Grass species: stargrass

Change of land use type: fencing off portion of river bed

Establishment and maintenance: activities, inputs and costs

Calculation of inputs and costs
  • Costs are calculated:
  • Currency used for cost calculation: Kenya shilling
  • Exchange rate (to USD): 1 USD = 70.0 Kenya shilling
  • Average wage cost of hired labour per day: 1.50
Most important factors affecting the costs
labour affects cost as it is required in large quantities
Establishment activities
  1. fencing (Timing/ frequency: after rains)
  2. mulching with bushes (Timing/ frequency: before rains)
  3. planting of sugarcane (Timing/ frequency: dry season)
  4. cuting grass for mulch (Timing/ frequency: rainy season)
  5. fencing riverbed to keep off animals (Timing/ frequency: after rain)
  6. planting grass (Timing/ frequency: after rain)
Maintenance activities
  1. fencing (Timing/ frequency: dry season / when height goes down)
  2. mulching with trash (Timing/ frequency: dry '' / after clearing)
  3. grass planting (Timing/ frequency: dry / before rains)
  4. sugarcane planting (Timing/ frequency: wet / end of rain)
  5. collection of mulch (Timing/ frequency: dry / biannual)
  6. fencing (Timing/ frequency: after rain /biannual)
  7. cutting grass for mulch (Timing/ frequency: rainy /biannual)
  8. scatterin thorn bushes (Timing/ frequency: during rain /biannual)
  9. fencing (Timing/ frequency: after rain / each cropping season)
  10. spreading brushwood (Timing/ frequency: after / annual)

Natural environment

Average annual rainfall
  • < 250 mm
  • 251-500 mm
  • 501-750 mm
  • 751-1,000 mm
  • 1,001-1,500 mm
  • 1,501-2,000 mm
  • 2,001-3,000 mm
  • 3,001-4,000 mm
  • > 4,000 mm
Agro-climatic zone
  • humid
  • sub-humid
  • semi-arid
  • arid
Specifications on climate
n.a.
Slope
  • flat (0-2%)
  • gentle (3-5%)
  • moderate (6-10%)
  • rolling (11-15%)
  • hilly (16-30%)
  • steep (31-60%)
  • very steep (>60%)
Landforms
  • plateau/plains
  • ridges
  • mountain slopes
  • hill slopes
  • footslopes
  • valley floors
Altitude
  • 0-100 m a.s.l.
  • 101-500 m a.s.l.
  • 501-1,000 m a.s.l.
  • 1,001-1,500 m a.s.l.
  • 1,501-2,000 m a.s.l.
  • 2,001-2,500 m a.s.l.
  • 2,501-3,000 m a.s.l.
  • 3,001-4,000 m a.s.l.
  • > 4,000 m a.s.l.
Technology is applied in
  • convex situations
  • concave situations
  • not relevant
Soil depth
  • very shallow (0-20 cm)
  • shallow (21-50 cm)
  • moderately deep (51-80 cm)
  • deep (81-120 cm)
  • very deep (> 120 cm)
Soil texture (topsoil)
  • coarse/ light (sandy)
  • medium (loamy, silty)
  • fine/ heavy (clay)
Soil texture (> 20 cm below surface)
  • coarse/ light (sandy)
  • medium (loamy, silty)
  • fine/ heavy (clay)
Topsoil organic matter content
  • high (>3%)
  • medium (1-3%)
  • low (<1%)
Groundwater table
  • on surface
  • < 5 m
  • 5-50 m
  • > 50 m
Availability of surface water
  • excess
  • good
  • medium
  • poor/ none
Water quality (untreated)
  • good drinking water
  • poor drinking water (treatment required)
  • for agricultural use only (irrigation)
  • unusable
Is salinity a problem?
  • Ja
  • Nee

Occurrence of flooding
  • Ja
  • Nee
Species diversity
  • high
  • medium
  • low
Habitat diversity
  • high
  • medium
  • low

Characteristics of land users applying the Technology

Market orientation
  • subsistence (self-supply)
  • mixed (subsistence/ commercial)
  • commercial/ market
Off-farm income
  • less than 10% of all income
  • 10-50% of all income
  • > 50% of all income
Relative level of wealth
  • very poor
  • poor
  • average
  • rich
  • very rich
Level of mechanization
  • manual work
  • animal traction
  • mechanized/ motorized
Sedentary or nomadic
  • Sedentary
  • Semi-nomadic
  • Nomadic
Individuals or groups
  • individual/ household
  • groups/ community
  • cooperative
  • employee (company, government)
Gender
  • women
  • men
Age
  • children
  • youth
  • middle-aged
  • elderly
Area used per household
  • < 0.5 ha
  • 0.5-1 ha
  • 1-2 ha
  • 2-5 ha
  • 5-15 ha
  • 15-50 ha
  • 50-100 ha
  • 100-500 ha
  • 500-1,000 ha
  • 1,000-10,000 ha
  • > 10,000 ha
Scale
  • small-scale
  • medium-scale
  • large-scale
Land ownership
  • state
  • company
  • communal/ village
  • group
  • individual, not titled
  • individual, titled
Land use rights
  • open access (unorganized)
  • communal (organized)
  • leased
  • individual
Water use rights
  • open access (unorganized)
  • communal (organized)
  • leased
  • individual
Access to services and infrastructure

Impacts

Socio-economic impacts
Crop production
decreased
x
increased


Sugar cane

farm income
decreased
x
increased


Sugar cane

Socio-cultural impacts
Ecological impacts
surface runoff
increased
x
decreased

Quantity before SLM: 60
Quantity after SLM: 20

soil moisture
decreased
x
increased

soil cover
reduced
x
improved

soil loss
increased
x
decreased

Quantity before SLM: 12
Quantity after SLM: 5

nutrient cycling/ recharge
decreased
x
increased

Off-site impacts

Cost-benefit analysis

Benefits compared with establishment costs
Short-term returns
very negative
x
very positive

Long-term returns
very negative
x
very positive

Benefits compared with maintenance costs
Short-term returns
very negative
x
very positive

Long-term returns
very negative
x
very positive

Climate change

-

Adoption and adaptation

Percentage of land users in the area who have adopted the Technology
  • single cases/ experimental
  • 1-10%
  • 11-50%
  • > 50%
Of all those who have adopted the Technology, how many have done so without receiving material incentives?
  • 0-10%
  • 11-50%
  • 51-90%
  • 91-100%
Number of households and/ or area covered
30 households (1% of the area stated)
Has the Technology been modified recently to adapt to changing conditions?
  • Ja
  • Nee
To which changing conditions?
  • climatic change/ extremes
  • changing markets
  • labour availability (e.g. due to migration)

Conclusions and lessons learnt

Strengths: land user's view
Strengths: compiler’s or other key resource person’s view
  • This innovation demonstrates how productive use can be made of sub-surface moisture in sand rivers in arid areas while simultaneously protecting the riverbed and bank from erosion
  • Farm income increase through land reclamation
Weaknesses/ disadvantages/ risks: land user's viewhow to overcome
Weaknesses/ disadvantages/ risks: compiler’s or other key resource person’s viewhow to overcome
  • Planting within a riverbed is, strictly speaking,
    against regulations. Such technologies should not be attempted without consulting the local agricultural office.
  • The fence is constructed with thorn bush cuttings which have to be constantly replenished A live fence is recommended as an alternative to constantly having to replenish the fence with cut thorn
    bush. The fence is required to avoid grazing of the cane by domestic livestock.

References

Compiler
  • Kithinji Mutunga
Editors
Reviewer
  • David Streiff
  • Alexandra Gavilano
Date of documentation: Junie 6, 2011
Last update: Sept. 4, 2019
Resource persons
Full description in the WOCAT database
Linked SLM data
Documentation was faciliated by
Institution Project
Key references
  • Farm management Guidelines. 1989.: MOA, Nairobi
  • Kithinji M., Critchley W. 2001. Farmers' initiatives in land husbandry: Promising technologies for the drier areas of East Africa. RELMA Technical Report series no. 27:
This work is licensed under Creative Commons Attribution-NonCommercial-ShareaAlike 4.0 International