Visitors learning from the technology

In-situ compost cultivation or ‘pattern farming’ (Tanzania, United Republic of)

Kilimo cha mfumo (Kiswahili)

Description

In-situ compost trench cultivation

The system is based on trench cultivation. This involves excavation of trenches 0.6 m deep and 0.6 m wide, more or less across the slope, at a spacing of 0.9 m apart, edge to edge. The trenches are dug in the dry period, then filled with crop residues, grass and other organic trash, and finally back-filled with soil.
The surface is deliberately left some centimetres below ground level so that it can capture runoff. Associated with the trenching, a furrow to harvest rainwater is formed to lead water into the field from outside, and an end bund in the field is built up to prevent its loss. Between trenches a leguminous crop such as groundnuts is grown, while maize, sweet potatoes and tomatoes are grown on the trenches. In the first year, the farmer plants at the sides of the trench to avoid damage to crop roots by the heat generated by decomposition. Thereafter crops are planted in the middle. In years of good rainfall it is possible to grow an opportunistic second crop, making use of stored soil moisture. After four years the trench is re-dug, filled with organic matter, and the cycle begins. Further additions/ improvements to the system (which is
constantly evolving) are (i) the addition of cattle urine and waste water from the household to hasten decomposition of grass materials; and (ii) mulching between the trenches with crop stover at the end of the season.

Purpose of the Technology: The technology comprises a structural measure, dedicated to improvement of the land for annual cropping. In respect to soil and water conservation it primarily addresses soil fertility and soil moisture problems. It achieves impact through increasing organic matter and water stored in the soil. Ecological benefits include increase in soil moisture, improved soil fertility and protection of the land from surface erosion.

Establishment / maintenance activities and inputs: The land was completely bare before the technology and is now productive. Compared with neighbouring farms yields are estimated to be at least 50% higher, and the farmer considers the benefits to be ‘very positive’ in relation to the costs. This is reflected in his increased farm income. Those cost, however, are estimated at around 400 person days per hectare for initial establishment.

Natural / human environment: This technology was designed by a retired agricultural field agent on his 3 ha of land. The importance of this particular innovation lies in the fact that the originator has mixed and matched tradition and modern practices to tailor-make a system that suits his own situation.

Location

Location: Dodoma rural, Dodoma, Tanzania, United Republic of

No. of Technology sites analysed:

Geo-reference of selected sites
  • 35.374, -7.2577

Spread of the Technology: evenly spread over an area (approx. 10-100 km2)

In a permanently protected area?:

Date of implementation: less than 10 years ago (recently)

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
    • Annual cropping: cereals - maize, oilseed crops - groundnuts, root/tuber crops - sweet potatoes, yams, taro/cocoyam, other, tomatoes
    Number of growing seasons per year: 1
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 - Wt: loss of topsoil/ surface erosion
  • chemical soil deterioration - Cn: fertility decline and reduced organic matter content (not caused by erosion)
  • water degradation - Ha: aridification
SLM group
  • integrated soil fertility management
SLM measures
  • agronomic measures - A2: Organic matter/ soil fertility
  • structural measures - S4: Level ditches, pits

Technical drawing

Technical specifications
Cross-section of compost trench cultivation

Location: Dodoma. Tanzania

Technical knowledge required for field staff / advisors: moderate

Technical knowledge required for land users: low

Main technical functions: control of dispersed runoff: retain / trap, increase in organic matter, water harvesting, increase in soil fertility

Secondary technical functions: reduction of slope length, improvement of ground cover, increase of surface roughness

Legume inter-planting
Remarks: between trenches

Manure / compost / residues
Material/ species: compost, grass, other organic trash
Remarks: trenches filled with organic material

Furrows (drainage, irrigation)
Remarks: to harvest rainwater and bring it into the field

Structural measure: trench 2'*2'
Vertical interval between structures (m): 0.6
Spacing between structures (m): 0.3
Depth of ditches/pits/dams (m): 0.6
Length of ditches/pits/dams (m): 0.15
Height of bunds/banks/others (m): 0.2

Establishment and maintenance: activities, inputs and costs

Calculation of inputs and costs
  • Costs are calculated:
  • Currency used for cost calculation: n.a.
  • Exchange rate (to USD): 1 USD = n.a
  • Average wage cost of hired labour per day: n.a
Most important factors affecting the costs
labour for trench cultivation
Establishment activities
  1. layout, excavation, construction of bunds (Timing/ frequency: before rains)
  2. filling of trash and organic matter (Timing/ frequency: during rains)
Establishment inputs and costs
Specify input Unit Quantity Costs per Unit (n.a.) Total costs per input (n.a.) % of costs borne by land users
Labour
Labour persons/day/ha 417.0 1.9 792.3 100.0
Equipment
Tools ha 1.0 8.5 8.5 100.0
Plant material
Seeds ha 1.0 7.5 7.5 100.0
Total costs for establishment of the Technology 808.3
Total costs for establishment of the Technology in USD 808.3
Maintenance activities
  1. excavating the trenches (Timing/ frequency: aug-nov / occassionally)
  2. collecting of organic matter (Timing/ frequency: before rains / occassionally)
  3. burying of the organic matter (Timing/ frequency: before rains / occassionally)
  4. sowing of seeds (Timing/ frequency: during rain / annually)
  5. harvesting (Timing/ frequency: dry season / annually)
  6. after 3 years excavate (Timing/ frequency: dry season/after 3years)
  7. add organic matter (Timing/ frequency: each cropping season)
Maintenance inputs and costs
Specify input Unit Quantity Costs per Unit (n.a.) Total costs per input (n.a.) % of costs borne by land users
Labour
Labour persons/day/ha 139.0 1.9 264.1 100.0
Equipment
Tools ha 1.0 8.5 8.5 100.0
Plant material
Seeds ha 1.0 7.5 7.5 100.0
Total costs for maintenance of the Technology 280.1
Total costs for maintenance of the Technology in USD 280.1

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
Also 500-750 mm
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

fodder production
decreased
x
increased

farm income
decreased
x
increased

Socio-cultural impacts
community institutions
weakened
x
strengthened

national institutions
weakened
x
strengthened

Ecological impacts
soil moisture
decreased
x
increased

soil cover
reduced
x
improved

soil loss
increased
x
decreased

soil fertility
decreased
x
increased

biodiversity
diminished
x
enhanced

Off-site impacts
downstream flooding (undesired)
increased
x
reduced

downstream siltation
increased
x
decreased

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
60 households (20 percent of land users)
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
  • improves soil fertility
  • improves soil moisture
Strengths: compiler’s or other key resource person’s view
  • improve soil fertility from organic matter

    How can they be sustained / enhanced? replace organic matter
  • conserve more moisture

    How can they be sustained / enhanced? improves moisture
  • increase yields by 300%
Weaknesses/ disadvantages/ risks: land user's viewhow to overcome
Weaknesses/ disadvantages/ risks: compiler’s or other key resource person’s viewhow to overcome
  • heavy earth works hire labour
  • not applicable to certain soils like graverly

References

Compiler
  • Patrick Gervas Mbanguka Lameck
Editors
Reviewer
  • David Streiff
  • Alexandra Gavilano
Date of documentation: Feb. 28, 2011
Last update: Aug. 6, 2019
Resource persons
Full description in the WOCAT database
Linked SLM data
Documentation was faciliated by
Institution Project
Key references
  • farmer innovators workshop report: invades UNDP-DSM tanzania
  • 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