1.2 Contact details of resource persons and institutions involved in the assessment and documentation of the Technology

Name of the institution(s) which facilitated the documentation/ evaluation of the Technology (if relevant)

1.3 Conditions regarding the use of data documented through WOCAT

The compiler and key resource person(s) accept the conditions regarding the use of data documented through WOCAT:

Yes

2.1 Short description of the Technology

Definition of the Technology:

In-situ compost trench cultivation

2.2 Detailed description of the Technology

Description:

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.

2.3 Photos of the Technology

2.5 Country/ region/ locations where the Technology has been applied and which are covered by this assessment

Country:

Tanzania, United Republic of

Region/ State/ Province:

Dodoma

Further specification of location:

Dodoma rural

Specify the spread of the Technology:

• evenly spread over an area

If precise area is not known, indicate approximate area covered:

• 10-100 km2

Map

×

2.6 Date of implementation

If precise year is not known, indicate approximate date:

• less than 10 years ago (recently)

2.7 Introduction of the Technology

Specify how the Technology was introduced:

• through land users' innovation

Comments (type of project, etc.):

farmer intiative

3.1 Main purpose(s) of the Technology

• improve production
• reduce, prevent, restore land degradation

3.2 Current land use type(s) where the Technology is applied

Cropland

• Annual cropping

Annual cropping - Specify crops:

• cereals - maize
• oilseed crops - groundnuts
• root/tuber crops - sweet potatoes, yams, taro/cocoyam, other

• tomatoes

Number of growing seasons per year:

• 1

Specify:

Longest growing period in days: 120; Longest growing period from month to month: Dec - Apr; Second longest growing period in days: 90; Second longest growing period from month to month: Sep - Dec

Comments:

Major land use problems (compiler’s opinion): declining soil fertility, moderate erosion and declining soil cover

Major land use problems (land users’ perception): as above

3.5 SLM group to which the Technology belongs

• integrated soil fertility management

3.6 SLM measures comprising the Technology

agronomic measures

• A2: Organic matter/ soil fertility

structural measures

• S4: Level ditches, pits

Comments:

Type of agronomic measures: legume inter-planting, manure / compost / residues, furrows (drainage, irrigation)

3.7 Main types of land degradation addressed by the Technology

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

Comments:

Secondary types of degradation addressed: Ha: aridification

3.8 Prevention, reduction, or restoration of land degradation

Specify the goal of the Technology with regard to land degradation:

• restore/ rehabilitate severely degraded land

4.1 Technical drawing of the Technology

Technical specifications (related to technical drawing):

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

4.3 Establishment activities

4.4 Costs and inputs needed for establishment

Comments:

Duration of establishment phase: 12 month(s)

4.5 Maintenance/ recurrent activities

4.6 Costs and inputs needed for maintenance/ recurrent activities (per year)

4.7 Most important factors affecting the costs

Describe the most determinate factors affecting the costs:

labour for trench cultivation

5.1 Climate

5.2 Topography

Comments and further specifications on topography:

Slopes on average: Also hilly and gentle

Landforms: Also footslopes and valley floors

5.3 Soils

If available, attach full soil description or specify the available information, e.g. soil type, soil PH/ acidity, Cation Exchange Capacity, nitrogen, salinity etc.

Soil fertility is low

Soil drainage / infiltration is medium

Soil water storage capacity is medium

5.6 Characteristics of land users applying the Technology

Indicate other relevant characteristics of the land users:

Population density: 10-50 persons/km2

Annual population growth: 2% - 3%

3% of the land users are rich and own 35% of the land.
40% of the land users are average wealthy and own 40% of the land.
40% of the land users are poor and own 15% of the land.
17% of the land users are poor and own 10% of the land.

5.7 Average area of land used by land users applying the Technology

5.8 Land ownership, land use rights, and water use rights

Land ownership:

• individual, not titled
• individual, titled

6.1 On-site impacts the Technology has shown

Socio-economic impacts

Production

Income and costs

Socio-cultural impacts

Ecological impacts

Soil

Other ecological impacts

6.2 Off-site impacts the Technology has shown

6.4 Cost-benefit analysis

How do the benefits compare with the establishment costs (from land users’ perspective)?

How do the benefits compare with the maintenance/ recurrent costs (from land users' perspective)?

6.5 Adoption of the Technology

• 11-50%

If available, quantify (no. of households and/ or area covered):

60 households (20 percent of land users)

Of all those who have adopted the Technology, how many did so spontaneously, i.e. without receiving any material incentives/ payments?

• 91-100%

Comments:

60 land user families have adopted the Technology without any external material support

Comments on spontaneous adoption: estimates

There is a little trend towards spontaneous adoption of the Technology

Comments on adoption trend: This is not one of the most quickly adopted initiatives – almost certainly due to the considerable labour involved. However of the 20 who have copied Albert (or modified the idea, as one close neighbour has done) several are women.

6.7 Strengths/ advantages/ opportunities of the Technology

6.8 Weaknesses/ disadvantages/ risks of the Technology and ways of overcoming them

7.1 Methods/ sources of information

7.2 References to available publications

Title, author, year, ISBN:

farmer innovators workshop report

Available from where? Costs?

invades UNDP-DSM tanzania

Title, author, year, ISBN:

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