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)

Society for Community Development in Cambodia (SOFDEC) - Cambodia

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

Local Agricultural Research and Extension Centre (LAREC) - Cambodia

1.3 Condiciones referidas al uso de datos documentados mediante WOCAT

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

05/08/2014

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

Sí

1.4 Declaración de la sostenibilidad de la Tecnología descrita

¿La Tecnología aquí descrita resulta problemática en relación a la degradación de la tierra, de tal forma que no puede considerársela una tecnología sostenible para el manejo de la tierra?

No

2.1 Breve descripción de la Tecnología

Definición de la Tecnología:

Small-scale biogas systems fed with cow manure and water are implemented in order to supply the household with energy for cooking and lighting, as well as to produce fertilizer.

2.2 Descripción detallada de la Tecnología

Descripción:

In this case-study, a small-scale biogas system was introduced in order to generate both energy for home consumption and fertilizer. Small-scale biogas systems are implemented in different parts of the world, however the layout thereof varies considerably.
The model used in this case-study consists of different components (cf. technical drawing). First, there is an inlet where the land user puts cow manure mixed with water. On the bottom of the inlet, there is a board which closes the access to the bio-digester situated beneath the inlet. The board can be opened manually by pulling a string. Once the board is open, the fluid components go through a pipe which leads to the bio-digester. In the bio-digester, bacteria transform the organic matter into biogas (mainly methane and CO2) and slurry. At the other end of the digester, there is another pipe (outlet). The outlet is lower than the inlet, and due to the difference in pressure, the slurry is pushed out of the digester. The slurry is dried and applied to the fields two to three times a year with the help of an ox cart. It has similar effects on the plant growth as chemical fertilizer as it does not build up the soil organic matter as much as compost. The biogas, however, is pushed to the pipe situated on top of the digester and can be utilized for domestic uses. The gas is used for cooking and lighting.

The use of biogas allows reducing the expenses on charging batteries for the lighting, as well as reducing the firewood use (usually from deforestation) for cooking. The slurry reduces the expenses on chemical fertilizer in the fields and has the advantage of killing the weed and rice seeds present in the manure and crop residues.

For building the biogas system, there is governmental and NGO support. These two actors finance half of the construction costs. The other half is paid by the land user. Building a biogas system is quite costly, with about 400 $, and not all of the land users in the area can afford paying 50% of its price. However, the costs borne by the land user are paid off within a few years due to reduced expenses on firewood, chemical fertilizer, and charging batteries. The construction itself was undertaken by local companies.
The costs are paid off within a few years due to the reduced expenses on firewood, chemical fertilizer and battery charging.

The analysed area is flat (slope < 2%), tropic (dry and wet season), and the soils are mostly sandy or loamy. The soils contain little organic matter (low soil fertility, acidification, small amount of cattle, area has been deforested a long time ago) and the groundwater table is rather high (1-3 m during the dry season, on the surface during wet season).
Due to climate change, the rainfalls are more erratic, temperatures rise and droughts are more recurrent. Rice is the predominant crop grown in the area, since it serves as staple food (mix subsistence and commercial activities). Rice is often grown in monocultures and harvested once a year. Once the rice is harvested (dry season), the cattle are released to the paddy fields. The cattle is often replaced by hand tractors, which effects the production of manure but allows a higher amount of crop residues on the fields.
As an addition to rice, most land users grow vegetable and fruits in small home gardens (subsistence) and complement their income by producing handicrafts or through off farm income / remittances from family members working in other places. The increasing migration rate (the young generation leaves the villages to work in the cities, garment industry or abroad) results in a decrease of available labour force in the area which has detrimental effects on the agricultural activities. Furthermore, the civil war in the 1970s (Khmer Rouge) led to the loss of agricultural knowledge which different NGOs try to re-establish.

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:

• hace menos de 10 años (recientemente)

2.7 Introducción de la Tecnología

Especifique cómo se introdujo la Tecnología:

• mediante proyectos/ intervenciones externas

Comentarios (tipo de proyecto, etc.):

LWS (a Dutch NGO) in joint efforts with specialists from the National Biodigester Program NBP. Implementation in 2012

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

• mejorar la producción
• crear impacto económico benéfico

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

Comentarios:

Major land use problems (compiler’s opinion): Lack of organic matter, lack of water retention in soil, irregularity of rainfall, low soil fertility (sandy soil), monocultures, bare soil during dry season, ploughing.
Major land use problems (land users’ perception): Low soil fertility, lack of water.
Livestock is grazing on crop residues
Constraints of settlement / urban
Constraints of infrastructure network (roads, railways, pipe lines, power lines)

3.3 Información adicional sobre el uso de tierras

Número de temporadas de cultivo por año:

• 1

Especifique:

Longest growing period in days: 210, Longest growing period from month to month: June-December

3.4 Grupo MST al que pertenece la Tecnología

• tecnologías de eficiencia energética

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:

• 0.1-1 km2

Comentarios:

There are only 4 households in this village which apply the technology (lack of money and/or cattle). However, similar Technologies are introduced in other provinces – yet it is difficult to estimate the area covered. Estimation for this village.

3.6 Medidas MST que componen la Tecnología

Comentarios:

Main measures: management measures
Secondary measures: structural measures

3.7 Principales tipos de degradación del suelo encarados con la Tecnología

Comentarios:

Main causes of degradation: soil management (Ploughing, soil is left bare for several weeks), crop management (annual, perennial, tree/shrub) (Rice monoculture (rice as staple crop)), change of seasonal rainfall (More erratic beginning of wet season), droughts (On dry soil, rice cannot be planted and if already planted, rice cannot grow), labour availability (High migration rates from the villages to garment industry, cities or abroad, influence agricultural activities (e.g. broadcasting instead of transplanting of rice seedlings)), education, access to knowledge and support services (Khmer Rouge regime in the 1970s, a lot of knowledge got lost)
Secondary causes of degradation: over-exploitation of vegetation for domestic use (Rice straw is removed for different domestic uses (cattle, mushroom cultivation, etc.)), overgrazing (Cattle eats rice straw left after harvest, less organic matter on the field, grazing is not managed), change in temperature (More hot days), Heavy / extreme rainfall (intensity/amounts), land tenure (Some incidents of land grabbing, land use rights not clear, corruption), poverty / wealth

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
• reducir la degradación del suelo

4.1 Dibujo técnico de la Tecnología

4.2 Especificaciones técnicas/ explicaciones del dibujo técnico

Biodigester. Inlet: top left; gas outlet: top centre; digestion chambre: centre; and outlet: right. For the comlete building instructions contact the NBP.
Technical knowledge required for field staff / advisors: high (The most challenging part is the construction of the construction of the Biodigester.)
Technical knowledge required for land users: low
Main technical functions: increase in nutrient availability (supply, recycling,…)
Secondary technical functions: increase in organic matter

Structural measure: Biodigester. Round shape. Tiles and concrete.
Width of ditches/pits/dams (m): 4 m^3
Structural measure: Connecting pipes made of plastic
Construction material (concrete): Tiles are covered in concrete.
Construction material (other): The most challenging part is the construction of the Biodigester.
Other type of management: Change of energy supply system for home consumption.

4.3 Información general sobre el cálculo de insumos y costos

otra / moneda nacional (especifique):

Riel

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

4000,0

4.4 Actividades de establecimiento

	Actividad	Tipo de medida	Momento
1.	Construction of the biodigester by external experts. The land user did not help with the construction, he only paid 200 US$. The other 200 US$ were paid by the National Biodigester Program.	Estructurales	Dry season, when water table is low.

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
Material de construcción	Construction of biodigester		1,0	400,0	400,0	50,0
Costos totales para establecer la Tecnología					400,0

4.6 Actividades de establecimiento/ recurrentes

	Actividad	Tipo de medida	Momento/ frequencia
1.	Add manure and water to the inlet	Manejo	once per day all year round
2.	Collect residuals from biodigester, spread it out and let it dry, and finally put it on the field.	Manejo	3 times/year

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	Labour		1,0	121,5	121,5	100,0
Indique los costos totales para mantenecer la Tecnología					121,5

Comentarios:

Machinery/ tools: Cart to bring residues from the biodigester onto the fields.

The costs were calculated for 1 biodigester with a capacity of 4 m3.

4.8 Factores más determinantes que afectan los costos:

Describa los factores más determinantes que afectan los costos:

The most costly part of this Technology is the construction of the biodigester. Once the system is installed, the costs borne by the land user are low. Also, the land user can save money since he doesn’t need to buy firewood any more.

5.1 Clima

5.2 Topografía

5.3 Suelos

5.4 Disponibilidad y calidad de agua

Comentarios y especificaciones adicionales sobre calidad y cantidad de agua:

Ground water tabel and availability of surface water data during dry seasons. People use water for drinking after filtering or boiling.

5.5 Biodiversidad

Comentarios y especificaciones adicionales sobre biodiversidad:

Only degraded forests are in the area.

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 Leaders / privileged
Population density: 10-50 persons/km2
Annual population growth: 0.5% - 1%
Off-farm income specification: Handicraft, remittances and factory work.

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:

• comunitaria/ aldea
• individual, sin título

Derechos de uso de tierra:

• comunitarios (organizado)
• individual

Derechos de uso de agua:

• acceso abierto (no organizado)

Comentarios:

Land ownership is very complex. Most of the land belongs officially to the government, yet many land users hold a paper confirming they applied for a land title – but de iure, this paper is worthless.

5.9 Acceso a servicios e infraestructura

6.1 Impactos in situ demostrados por la Tecnología

Impactos socioeconómicos

Producción

Ingreso y costos

Impactos socioculturales

Impactos ecológicos

Ciclo de agua/ escurrimiento de sedimento

Suelo

Otros impactos ecológicos

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	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

Otras consecuencias relacionadas al clima

Otras consecuencias relacionadas al clima

	¿Cómo es que la tecnología soporta esto?
periodo reducido de crecimiento	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

• más de 50%

Si tiene la información disponible, cuantifique (número de hogares y/o área cubierta):

100% or 4 land user families

Comentarios:

100% of land user families have adopted the Technology with external material support
4 land user families have adopted the Technology with external material support
The farmers can ask the National Biodigester Program for subsidies, but need to pay half of it on their own. As the farmers often lack money and need at least 3 - 4 heads of cattle to produce enough manure while they switch more and more to hand tractors, not many farmers are building new biogas digesters.

6.7 Fuerzas/ ventajas/ oportunidades de la Tecnología

Fuerzas/ ventajas/ oportunidades desde la perspectiva del usuario de la tierra
Fertilizer production (sludge).
Saves money and time on the cooking fuel (previously wood) and electricity (charging batteries) for the light.
No weed seeds in the sludge compared to compost and raw manure if used as fertilizer.

Fuerzas/ ventajas/ oportunidades desde la perspectiva del compilador o de otra persona de referencia clave
Less deforestation for firewood.

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?
The residue does not improve the soil as much as compost.	Make compost in addition to biogas to enhance the soil organic matter.
The building costs are prohibitive	Increase subsidies from state or NGOs.
At least 3-4 heads of cattle or 4-5 pigs have to be kept to produce enough manure.	Diversify production with different animals.
Work has to be done each day to produce biogas.

Debilidades/ desventajas/ riesgos desde la perspectiva del compilador o de otra persona de referencia clave	¿Cómo sobreponerse a ellas?
Overgrazing could become a problem as more cattle needs to be kept.	Add slurry as a liquid fertilizer
Part of nitrogen is volatilized during the drying of the sludge.

7.1 Métodos/ fuentes de información

7.2 Vínculos a las publicaciones disponibles

Título, autor, año, ISBN:

NBP National Biodigester Program

¿Dónde se halla disponible? ¿Costo?

www.nbp.org.kh

Título, autor, año, ISBN:

Lam et al. 2009. Domestic Biogas Compact Course. University of Oldenburg.

¿Dónde se halla disponible? ¿Costo?

http://www.nbp.org.kh/publication/study_report/2_domestic_biogas%20.pdf

Título, autor, año, ISBN:

Gurung. 2009. Review of Literature on Effects of Slurry Use on Crop production. The Biogas Support Program