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)

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

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

1.4 Declaration on sustainability of the described Technology

Is the Technology described here problematic with regard to land degradation, so that it cannot be declared a sustainable land management technology?

No

2.1 Short description of the Technology

Definition of the Technology:

Fanya juu terraces stabilized with nappier grass and sweet potatoes are earth bunds created by digging a trench along a contour and throwing the soil up slope to form an embankment that is stabilized with nappier grass and during maintenance phase, the accumulated sediments are removed and thrown on the lower side and stabilized with sweet potatoes.

2.2 Detailed description of the Technology

Description:

The cross-sectional profile of a fanya juu terrace comprises an embankment to impound water, soil and nutrients, a storage area above the embankment to prevent overtopping by runoff and a berm or ledge to prevent the embankment soil from sliding bank into the trench. The trench below the embankment may or be retained. A Fanya juu terrace is often the first stage in the development of a bench terrace.

Purpose of the Technology: They effectively reduces slope-length, and hence soil erosion from steep croplands. In some cases, enlarged embankments are made to allow ponding of harvested runoff and, therefore, the structure can be used in water harvesting systems having external catchments. The soil bund retains water and thereby, safeguards yields even during droughts. In Embu County, farmers are very innovative. They ussually stabilize the up slope soil with nappier grass (fodder) and during the maintenance phase, the silt/sediments in the trench is scoped and thrown on the lower side where is stabilized with sweet potatoes vines.

Establishment / maintenance activities and inputs: The construction of fanya juu terraces is labor intensive and involves digging a trench on the contour and throwing the soil up slope to form an embankment. Construction is carried out after laying out pegs on the contour, or at a gradient, as required. A berm of 15cm to 30 cm is left to prevent the embankment soil up slope to form an embankment, which should be stabilized with grass. The excavated trench should be as narrow as possible to reduce wastage of cultivated land. Where the trench can be used for planting tree crops such as bananas, it should be wide enough to accommodate the crop. The embankment should be planted with perennial grass to stabilize it.

Natural / human environment: Fanya juu terraces are popular in smallholder farms particularly in semi arid areas where they are quite effective in conserving moisture and nutrients. They are applicable in areas where soils are too shallow for level bench terracing and on moderately steep slopes (e.g. below 20%) They are not suitable for stony soil. They normally develop into out ward sloping bench terraces after a few years depending on the amount of soil which moves down slope and lodges above the embankment.

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:

Kenya

Region/ State/ Province:

Eastern Province

Further specification of location:

Mbere South District

Specify the spread of the Technology:

• evenly spread over an area

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

• < 0.1 km2 (10 ha)

Map

×

2.7 Introduction of the Technology

Specify how the Technology was introduced:

• through land users' innovation

3.1 Main purpose(s) of the Technology

• improve production
• reduce, prevent, restore land degradation
• create beneficial economic impact

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

Cropland

• Annual cropping

Annual cropping - Specify crops:

• fodder crops - grasses
• root/tuber crops - sweet potatoes, yams, taro/cocoyam, other

Number of growing seasons per year:

• 1

Comments:

Major land use problems (compiler’s opinion): The technology is safe for soil erosion conservation
Major land use problems (land users’ perception): There has been a lot of erosion due to poor protective measures. But the technology has successively manged to curb the continued erosion
Future (final) land use (after implementation of SLM Technology): Cropland: Ca: Annual cropping

3.3 Has land use changed due to the implementation of the Technology?

Has land use changed due to the implementation of the Technology?

• No (Continue with question 3.4)

3.4 Water supply

Water supply for the land on which the Technology is applied:

• mixed rainfed-irrigated

3.5 SLM group to which the Technology belongs

• cross-slope measure

3.6 SLM measures comprising the Technology

structural measures

• S2: Bunds, banks

3.7 Main types of land degradation addressed by the Technology

soil erosion by water

• Wt: loss of topsoil/ surface erosion

Comments:

Main causes of degradation: soil management, Heavy / extreme rainfall (intensity/amounts), poverty / wealth
Secondary causes of degradation: labour availability

3.8 Prevention, reduction, or restoration of land degradation

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

• prevent land degradation
• restore/ rehabilitate severely degraded land

4.1 Technical drawing of the Technology

Technical specifications (related to technical drawing):

The technical drawing on the left hand side shows a typical fanya juu terrace stabilized with nappier grass on the upper slope and sweet potatoes vines on the lower down slope.

Location: Ena Location. Eastern Province
Date: 12.11.2012

Technical knowledge required for field staff / advisors: moderate (The extension officers need to demonstrate on how to construct the terraces)
Technical knowledge required for land users: high (The technology is good because it completely reduces soil losses)

Main technical functions: control of concentrated runoff: retain / trap

Author:

Paul Kahiga, 8444-00300 Nairobi Kenya

4.2 General information regarding the calculation of inputs and costs

other/ national currency (specify):

Kshs

If relevant, indicate exchange rate from USD to local currency (e.g. 1 USD = 79.9 Brazilian Real): 1 USD =:

100.0

4.3 Establishment activities

4.4 Costs and inputs needed for establishment

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

Comments:

length of the structure

4.7 Most important factors affecting the costs

Describe the most determinate factors affecting the costs:

labour

5.1 Climate

5.2 Topography

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: Medium
Soil drainage/infiltration: Good
Soil water storage capacity: Medium

5.4 Water availability and quality

5.5 Biodiversity

5.6 Characteristics of land users applying the Technology

Indicate other relevant characteristics of the land users:

Land users applying the Technology are mainly common / average land users
Population density: < 10 persons/km2
Annual population growth: 0.5% - 1%

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, titled

Land use rights:

• individual

Water use rights:

• individual

5.9 Access to services and infrastructure

6.1 On-site impacts the Technology has shown

Socio-economic impacts

Production

Income and costs

Socio-cultural impacts

Ecological impacts

Water cycle/ runoff

Soil

Biodiversity: vegetation, animals

6.3 Exposure and sensitivity of the Technology to gradual climate change and climate-related extremes/ disasters (as perceived by land users)

Climate-related extremes (disasters)

Meteorological disasters

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

Comments:

There is a moderate trend towards spontaneous adoption of the Technology

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