1.2 Detalles de contacto de las personas de referencia e instituciones involucradas en la evaluación y la documentación de la Tecnología

Nombre de la(s) institución(es) que facilitaron la documentación/ evaluación de la Tecnología (si fuera relevante)

International Centre for Research in Agroforestry (ICRAF) - Kenia

Nombre de la(s) institución(es) que facilitaron la documentación/ evaluación de la Tecnología (si fuera relevante)

KARI Headquarters (KARI Headquarters) - Kenia

Nombre de la(s) institución(es) que facilitaron la documentación/ evaluación de la Tecnología (si fuera relevante)

Jomo Kenyatta University (Jomo Kenyatta University) - Kenia

1.3 Condiciones referidas al uso de datos documentados mediante WOCAT

¿Cuándo se compilaron los datos (en el campo)?

08/02/2011

El compilador y la/s persona(s) de referencia claves aceptan las condiciones acerca del uso de los datos documentados mediante WOCAT:

Sí

2.1 Breve descripción de la Tecnología

Definición de la Tecnología:

Stonelines are constructed along the contours to slow down the speed of runoff, filter the soil and enhance water infiltration.

2.2 Descripción detallada de la Tecnología

Descripción:

In Kenya stone lines are mostly practiced in areas that receive 200-750 mm of annual rainfall with a spacing of 15-30 m between them. They are particularly common in areas where rocks are readily available, such as Mbeere, Laikipia, Baringo, Mwingi, Kitui and Tharaka. Since the stonelines are permeable they do not pond runoff water but instead, they slow down the speed, filter it and spread the water over the field, thus enhancing water infiltration and reducing soil erosion. They are built in series running along the slope. In addition, the stone barrier blocks and settles down the sediments transported from the upper slopes.

Purpose of the Technology: They are often used to rehabilitate eroded and abandoned land. The advantages of stonelines include; slowing down the runoff thereby increasing infiltration and soil moisture. They also induce a natural process of terracing, reducing erosion and rehabilitation of eroded lands by trapping silt. They are easy to design and construct and since the stone line structure is permeable there is no need for construction of spillways to drain the excess runoff water. When it rains, the soil builds up on the upslope side of the stonelines and over time a natural terrace is formed.

Establishment / maintenance activities and inputs: The stonelines are spaced 15-30 m apart, a shorter distance being used for the steeper slopes. Stonelines are normally suitable on gentle slopes. Slopes above 35% should be avoided. They are established in the following manner: first, the contour line are marked out with the help of a tube level or line levels. In this region here, it is done with the help of the frontline agricultural extension officers. Secondly, a shallow foundation trench is dug across the slope (5-10 cm to 30 cm deep) using basic farm equipments (jembes or hoes). As shown on the above photographs, the larger stones are put on the down slope side of the trench while the smaller stones are used to build the rest of the bund. The smallest stones are used to fill the gaps and increase the heights of the bunds up to the desired level. Farmers plant fruit trees (pawpaws) as show in the photograph above on the upper part. The trees utilises the moisture and rich sediments deposited on the upper part. The stonelines can be reinforced with earth, or crop residues to make them more stable. Maintenance of stonelines is done by repairing the already damaged /fallen stoneline that may have been knocked down or disarranged by livestock or by human beings. In this case animal access needs to be limited and/or the bund should be laid out in a way that allows the animals to pass through.

Natural / human environment: In the lower Mbeere South District where the stoneline technologies is largely practiced, unless there are stones in the individual farms, it might be difficult to import stones from other farms as the exercise can be labor intensive. In this catchment, the Ministry of Agriculture through the front line extension officers has taken a lead role in encouraging farmers to adopt the technology especially the farms which have many stones. Most of the farmers who have implemented this technology in the Lower Mbeere South District learn from the ones who are already practicing through field days or individual initiatives.

2.3 Fotografías de la Tecnología

2.5 País/ región/ lugares donde la Tecnología fue aplicada y que se hallan comprendidos por esta evaluación

2.6 Fecha de la implementación

Si no se conoce el año preciso, indique la fecha aproximada:

• 10-50 años atrás

2.7 Introducción de la Tecnología

Especifique cómo se introdujo la Tecnología:

• mediante la innovación de usuarios de tierras

Comentarios (tipo de proyecto, etc.):

The land had too many stones which inhibited operations. By removing the stones, the farmer placed them in line along the contour.

3.1 Propósito(s) principal(es) de la Tecnología MST

• reducir, prevenir, restaurar la degradación del suelo

3.2 Tipo(s) actuales de uso de la tierra donde se aplica la Tecnología

Comentarios:

Major land use problems (compiler’s opinion): Limited cultivation land due to hindrances that are brought about by the scattered stones on the land's surface.

Major land use problems (land users’ perception): Soil erosion because of lack of soil and water conservation structures that leads to low land productivity.

Future (final) land use (after implementation of SLM Technology): Cropland: Ca: Annual cropping

Si el uso de la tierra ha cambiado debido a la implementación de la Tecnología, indique el uso de la tierra antes de la implementación de la Tecnología.

Cropland: Ct: Tree and shrub cropping

3.3 Información adicional sobre el uso de tierras

Provisión de agua para la tierra donde se aplica la Tecnología:

• de secano

Número de temporadas de cultivo por año:

• 2

Especifique:

Longest growing period in days: 90 Longest growing period from month to month: March-May Second longest growing period in days: 90 Second longest growing period from month to month: October - December

3.4 Grupo MST al que pertenece la Tecnología

• diversión y drenaje de agua

3.5 Difusión de la Tecnología

Especifique la difusión de la Tecnología:

• distribuida parejamente sobre un área

Si la tecnología se halla difundida homogéneamente en un área, indique el área aproximada que cubre:

• < 0.1 km2 (10 ha)

Comentarios:

Not many farmers are practicing stonelines, the farmers who are practicing are copying from some successful farmers within their neighborhood. They also corroborate with the local agricultural extension officers from the Ministry of Agriculture (MoA) to show them how to construct the stonelines along the contours.

3.6 Medidas MST que componen la Tecnología

3.7 Principales tipos de degradación del suelo encarados con la Tecnología

Comentarios:

Main type of degradation addressed: Wt: loss of topsoil / surface erosion

Main causes of degradation: soil management, Heavy / extreme rainfall (intensity/amounts), poverty / wealth, labour availability (Construction of the technology is labour intensive)

Secondary causes of degradation: deforestation / removal of natural vegetation (incl. forest fires)

3.8 Prevención, reducción o restauración de la degradación del suelo

Especifique la meta de la Tecnología con relación a la degradación de la tierra:

• prevenir la degradación del suelo
• restaurar/ rehabilitar tierra severamente degradada

Comentarios:

Secondary goals: mitigation / reduction of land degradation

4.1 Dibujo técnico de la Tecnología

4.2 Especificaciones técnicas/ explicaciones del dibujo técnico

This is a technical drawing representing a cross-section view of how the stonelines are constructed by the emerging farmers in the lower Mbeere South District.

First, a small trench is dug along an established contour line, the farmer starts arranging the stones with reference to their sizes. The bigger ones are arranged on the lower side and the small ones on the upper side as shown on the technical drawing.

By so doing, the eroded soils are trapped on the upper side by the small pebbles, allowing the water to pass through at lower speed hence low erosive capacity.

Location: Ntharawe. Lower Mbeere South District

Date: 2011-08-02

Technical knowledge required for field staff / advisors: moderate (In order to implement this technology, the farmers contact the front line agricultural extension officer in order to assist in making the contours.)

Technical knowledge required for land users: high (Stone required placement of a certain order. Big stone on the lower side and small stones on the upper side-Vertically)

Main technical functions: water spreading, sediment retention / trapping, sediment harvesting

Secondary technical functions: reduction of slope angle

Bund/ bank: graded
Spacing between structures (m): 15
Height of bunds/banks/others (m): 0.8
Width of bunds/banks/others (m): 1.2
Length of bunds/banks/others (m): 27.6

Slope (which determines the spacing indicated above): 8%

Lateral gradient along the structure: 8%

4.3 Información general sobre el cálculo de insumos y costos

Especifique cómo se calcularon los costos e insumos:

• por unidad de Tecnología

otra / moneda nacional (especifique):

Kshs

Indique la tasa de cambio de USD a la moneda local (si fuese relevante): 1 USD =:

80,0

4.4 Actividades de establecimiento

	Actividad	Tipo de medida	Momento
1.	Establish a contour line and dig up a trench upon which the stones will be arranged	Estructurales	yearly
2.	stones are collected and arranged along the established trench. The big boulders are reduced to the required sizes by the use of mattocks	Estructurales	once
3.	The big stones are arranged on the lower side and the rest follows with respect to their sizes on the upper side	Estructurales
4.	This formation is done per meter length. Mostly is charged 150Kshs per meter.	Estructurales

4.5 Costos e insumos necesarios para el establecimiento

	Especifique insumo	Unidad	Cantidad	Costos por unidad	Costos totales por insumo	% de los costos cubiertos por los usuarios de las tierras
Mano de obra	Establish a contour line	Persons/day	0,5	3,76	1,88	100,0
Mano de obra	Reduce stone size	Persons/day	0,5	3,76	1,88	100,0
Mano de obra	Arranging stones	Persons/day	0,5	3,76	1,88	100,0
Equipo	Mattock	pieces	1,0	18,75	18,75	100,0
Equipo	Wheelbarrow	pieces	1,0	20,0	20,0	100,0
Material de construcción	Stone	no	1,0	1,88	1,88	100,0
Costos totales para establecer la Tecnología					46,27

Comentarios:

Duration of establishment phase: 1 month(s)

4.6 Actividades de establecimiento/ recurrentes

	Actividad	Tipo de medida	Momento/ frequencia
1.	Repair/Rearrange stone on stone line after a rainy seasons or when people and animals have destroyed the stone line.	Estructurales	yearly during dry season

4.7 Costos e insumos necesarios para actividades de mantenimiento/ recurrentes (por año)

	Especifique insumo	Unidad	Cantidad	Costos por unidad	Costos totales por insumo	% de los costos cubiertos por los usuarios de las tierras
Mano de obra	Repair/Rearrange stone	mandays/acre	14,0	2,5	35,0	100,0
Indique los costos totales para mantenecer la Tecnología					35,0

Comentarios:

Machinery/ tools: A wheel barrow (for carrying) and mattocks (for breaking) may be used

The cost applies for the year 2011 and was calculated per metre square, metre length, metre height and metre width.

4.8 Factores más determinantes que afectan los costos:

Describa los factores más determinantes que afectan los costos:

The system is labour intensive and hence will affect the cost of constructing the stonelines. However, availability of farm equipments like wheelbarrows, mattocks or oxen will help reduce the total cost and time required for construction and maintaining the stonelines. On steep slopes, the spacing between the lines is small as compared to a relatively gentle slope.

5.1 Clima

5.2 Topografía

5.3 Suelos

Si se halla disponible, adjunte una descripción completa de los suelos o especifique la información disponible, por ej., tipo de suelo, pH/ acidez de suelo, capacidad de intercambio catiónico, nitrógeno, salinidad, etc. :

Soil texture: With a lot of stones

Soil fertility is medium

Soil drainage / infiltration is medium

Soil water storage capacity is medium

5.4 Disponibilidad y calidad de agua

Comentarios y especificaciones adicionales sobre calidad y cantidad de agua:

Availability of surface water: The rivers are seasonal, water availability is from river beds if not during the rainy seasons

5.5 Biodiversidad

5.6 Las características de los usuarios de la tierra que aplican la Tecnología

Indique otras características relevantes de los usuarios de las tierras:

Land users applying the Technology are mainly common / average land users

Population density: 10-50 persons/km2


Annual population growth: < 0.5%

80% of the land users are poor.

5.7 Área promedio de la tierra que pertenece a o es arrendada por usuarios de tierra que aplican la Tecnología

5.8 Tenencia de tierra, uso de tierra y derechos de uso de agua

Tenencia de tierra:

• individual, con título

5.9 Acceso a servicios e infraestructura

6.1 Impactos in situ demostrados por la Tecnología

Impactos socioeconómicos

Producción

Ingreso y costos

Otros impactos socioeconómicos

Impactos socioculturales

Impactos ecológicos

Suelo

Biodiversidad: vegetación, animales

Reducción de riesgos de desastres y riesgos climáticos

6.2 Impactos fuera del sitio demostrados por la Tecnología

6.3 Exposición y sensibilidad de la Tecnología al cambio climático gradual y a extremos relacionados al clima/ desastres (desde la percepción de los usuarios de tierras)

Cambio climático gradual

Cambio climático gradual

	Estación	tipo de cambios climáticos/ climas extremos	¿Cómo es que la tecnología soporta esto?
temperatura anual		incrementó	bien

Extremos (desastres) relacionados al clima

Desastres climatológicos:

	¿Cómo es que la tecnología soporta esto?
tormenta de lluvia local	no muy bien
tormenta de viento	bien

Desastres climatológicos

	¿Cómo es que la tecnología soporta esto?
sequía	bien

Desastres hidrológicos

	¿Cómo es que la tecnología soporta esto?
inundación general (río)	no muy bien

6.4 Análisis costo-beneficio

¿Cómo se comparan los beneficios con los costos de establecimiento (desde la perspectiva de los usuarios de tierra)?

¿Cómo se comparan los beneficios con los costos de mantenimiento/ recurrentes (desde la perspectiva de los usuarios de tierra)?

6.5 Adopción de la Tecnología

Comentarios:

There is a moderate trend towards spontaneous adoption of the Technology

Comments on adoption trend: The technology is mainly practiced on the farms with stones even though the farmers admit that the task of construction is labour intensive. However, these not withstanding, the farmers do acknowledge that the technology is beneficial since they can see the results of yields from the ones who are already practicing.

6.7 Fuerzas/ ventajas/ oportunidades de la Tecnología

Fuerzas/ ventajas/ oportunidades desde la perspectiva del usuario de la tierra
By concentrating the stones along a contour, the farmer is able to make use of the land which otherwise is not possible if the stones are scatered. How can they be sustained / enhanced? Farmers should be encouraged to learn from one another but they should also seek advice from extension officers in making the contours.
The cost of replacement of farm equipments (jembes, forks and pangas) is reduced since they aren't broken by stones during land preparation.

Fuerzas/ ventajas/ oportunidades desde la perspectiva del compilador o de otra persona de referencia clave
The stones for constructing the technology are readily available in most of the farms. How can they be sustained / enhanced? Encouraging farmers to use the available stones to put up the technology.
Stoneline technology prevents soil loss due to erosion. How can they be sustained / enhanced? Modification of the technology to allow more infiltration.
No high level technical knowledge is required for construction of stoneline technology. How can they be sustained / enhanced? More farmers should be encouraged to adopt the technology since they dont need a high level of technical knowledge.
Stone lines technology can be modified to prevent soil and water from running off on the side of stone line ridge. How can they be sustained / enhanced? Construction of side ridges.

6.8 Debilidades/ desventajas/ riesgos de la Tecnología y formas de sobreponerse a ellos

Debilidades/ desventajas/ riesgos desde la perspectiva del usuario de la tierra	¿Cómo sobreponerse a ellas?
Contour profiling is challenging.	Assistance from the front line agricultural extension officers.

Debilidades/ desventajas/ riesgos desde la perspectiva del compilador o de otra persona de referencia clave	¿Cómo sobreponerse a ellas?
Labour intensive.	When constructing, always move the stones downslope by gravity instead of moving upwards i.e. start from the contours from the upper side
The technology only allows the soil to deposit on the upper side of the stoneline but water passes through.	Proper arrangement of the stones should be enhanced basing on their sizes.
Increased habitats for snakes and other dangerous creatures like scorpions that hide on the stonelines.	Where there creatures are prone, the farmers should be careful.

7.2 Vínculos a las publicaciones disponibles

Título, autor, año, ISBN:

Thomas, D.B. (eds) 1997. Soil and Water Conservation Manual for Kenya. Soil and Water Conservation Branch. Ministry of Agriculture, Livestock Development and Marketing. 210 p.

Título, autor, año, ISBN:

Critchley W and Seigert K (1991) Water Harvesting. FAO