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)?

14/08/2014

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:

Rice husks as well as empty seeds are pyrolised and used as a soil amendment in the rice seed beds and the vegetable gardens.

2.2 Descripción detallada de la Tecnología

Descripción:

Biochar is the residue left after the pyrolysis of any organic matter and is used as a soil amendment. Pyrolysis occurs when the organic matter is heated in anaerobic conditions, which is usually done in specially designed kilns. Sometimes it is also made in a conventional fire, which is extinguished before the char turns to ash. Agricultural wastes like rice husks or unfilled grains are mainly used. Biochar can have many positive effects on the soil and plants:
-It buffers the pH, and has usually a high pH due to theash content.
-Due to its porous structure, it holds water and serves as refuge for microorganisms.
-It absorbs and adsorbs nutrients, both cations and anions. They are available for the plant roots.
-It can increase the resistance of plants to diseases.
Due to all these effects, the increased yields are higher than those that can be achieved only through the nutrients contained in the Biochar itself. Biochar is and was used in many parts of the world as soil amendment, with some benefits persisting for centuries. In Cambodia it was used during the Pol Pot regime to reduce the smell of the human faeces that were used on the fields due to a lack of other fertilizers. Today research in the Biochar domain is increasing, especially since the discovery of the man-made terra preta soils in South America.

Biochar is mainly used to increase the fertility, water holding capacity and carbon content of the soil. The fact that the benefits of Biochar addition to the soil remain for several years, unlike chemical fertilizers, makes it attractive to farmers. Other purposes, like the increased resistance of plants to diseases and buffering of nutrients are also of importance.

Biochar was introduced or reintroduced trough different NGOs, JICA (Japanese International Cooperation Agency) in this case study. Because of knowledge exchange between farmers, a rice husk char/ash mix, as residue from the pottery baking, was used already in 2011. In 2013 JICA borrowed a Biochar kiln to the local farmer self-help group with a training, so they could produce Biochar by themselves. The inner part of the kiln (cf. technical drawing) is filled with wood and lit. It is then put into an empty oil barrel, which is filled with rice husks. The heat pyrolyses the husks from the bottom to the top of the barrel, and the gases are burned in the inner part of the kiln and the chimney. Just before the upper part is pyrolysed, the husks are extinguished. There is a weight loss of about 50 to 60 % caused by this process. The Biochar is added to the fields after ploughing, and the fields are harrowed. In this case study, Biochar is used both in rice seed beds and in a vegetable patch. Concentrations of 0.5 kg/m2 are used in the rice seed bed, and 2.5 kg for the vegetables. Due to the little available quantities of husks, Biochar is not applied to the field yet. The use of Biochar is spreading quickly from farm to farm

The analysed area is flat (slope < 2%), with a tropical climate (dry season from November to May and wet season from June to October), and the soils are mostly sandy or loamy. The soil has a low fertility, contains little organic matter, and acidifies. The area has been deforested a long time ago, and the groundwater table is rather high (1-2 m during the dry season, on the surface during wet season).
Due to climate change, farmers notice more erratic rainfall, temperature rises and more recurrent droughts. Rice is the predominant crop grown in the area, since it serves as staple food (mix subsistence and commercial activities). Cattle are usually grazing on the fields after the harvest, without much control. Thus the cattle grazes too often and too much on the same spot, leading to degradation.
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. Several NGOs are trying to re-establish the knowledge.

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.):

It was introduced in 2010 by JICA, the Japanese International Cooperation Agency.

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

• mejorar la producción

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

Comentarios:

Major land use problems (compiler’s opinion): Soil fertility decline, water availability
Major land use problems (land users’ perception): Water availability. Interestingly the farmer says that soil fertility is not a problem, as the farmers know about the use of compost. The compost application is the problem.

3.3 Información adicional sobre el uso de tierras

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

• mixta de secano – irrigada

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

• manejo integrado de la fertilidad del suelo

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:

Area unknown and rapidly spreading.

3.6 Medidas MST que componen la Tecnología

3.7 Principales tipos de degradación del suelo encarados con la Tecnología

Comentarios:

Main causes of degradation: soil management (Ploughing and bare soil during dry season.), labour availability (Farmers go to work in the garment industry, in construction, or sell their labor elsewhere.)
Secondary causes of degradation: deforestation / removal of natural vegetation (incl. forest fires) (Deforestation happened many years ago.), overgrazing (Uncontrolled grazing during dry season.), change in temperature (More hot days according to UNDP and farmers.)

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:

• reducir la degradación del suelo

4.1 Dibujo técnico de la Tecnología

4.2 Especificaciones técnicas/ explicaciones del dibujo técnico

Biochar kiln. In the inner part, the combustion chamber, a wooden fire is lit. The burning chamber is then placed in the oil barrel, which is filled with rice husks. The heat pyrolyses the husks, the gas burn in the chamber and chimney. When pyrolysis is almost completed, the char is extinguished.
Kampong Chhnang
Date: 2014

Technical knowledge required for field staff / advisors: high
Technical knowledge required for land users: moderate (When farmers only buy Biochar the required technical knowledge is low.)
Main technical functions: increase in organic matter, increase in nutrient availability (supply, recycling,…)
Secondary technical functions: improvement of surface structure (crusting, sealing), improvement of topsoil structure (compaction)

Manure / compost / residues
Material/ species: Rice husk Biochar (together with compost, which he already did before)
Quantity/ density: 0.5-2.5
Remarks: Entity: kg/m^2. Distributing on fields and harrowing.

4.3 Información general sobre el cálculo de insumos y costos

otra / moneda nacional (especifique):

Riels

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.	biochar kiln

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
Equipo	kiln		1,0	50,0	50,0
Costos totales para establecer la Tecnología					50,0

4.6 Actividades de establecimiento/ recurrentes

	Actividad	Tipo de medida	Momento/ frequencia
1.	Biochar making	Agronómicas	Whenever there is time
2.	Adding Biochar to the fields after the compost was plowed in, and harrowing.	Agronómicas	Yearly, before planting.

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	20,0	20,0	100,0
Equipo	machine use		1,0	0,25	0,25	100,0
Material para plantas	rise husks		1,0	4,0	4,0	100,0
Indique los costos totales para mantenecer la Tecnología					24,25

Comentarios:

The costs are indicated per unit; a unit is one biochar kiln used on 1 a. The costs were calculated in 2014 for the vegetable beds, where the farmer uses around 2.5 kg/m2. He also uses Biochar on the rice seedling bed, with concentrations of around 0.5 kg/m2, 5 times less than in the vegetable patch. In the vegetable patch the farmer plants cucumber, pumpkin, onion, watermelon and leaf vegetables in the early wet season, before planting rice.

4.8 Factores más determinantes que afectan los costos:

Describa los factores más determinantes que afectan los costos:

The factors affecting the cost the most are the biochar kiln, and the amount of added Biochar.

5.1 Clima

5.2 Topografía

5.3 Suelos

5.4 Disponibilidad y calidad de agua

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% - 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 users have a title that is not recognized by the state.

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

Suelo

Biodiversidad: vegetación, animales

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 se sabe
tormenta de viento	no se sabe

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)?

Comentarios:

The costs for the pyrolysis kiln were not borne by the land user. But as the farmer of this case study wants to build an own kiln as soon as the NGO needs it again, it is positive.

6.5 Adopción de la Tecnología

Comentarios:

100% of land user families have adopted the Technology with external material support
100 land user families have adopted the Technology with external material support
Considering only the farmers applying the technology with this stove. Other farmers buy Biochar, or burn the rice husks and extinguish them. But those farmers are nearly impossible to quantify as it changes quickly. The support was the kiln, which is only a small part of the costs.
Considering only the farmers applying the technology with this stove. Other farmers buy Biochar, or burn the rice husks and extinguish them. But those farmers are nearly impossible to quantify as it changes quickly.
In another area of Cambodia where the Ministry of Agriculture, Forestry and Fisheries (MAFF) is doing Biochar research, there was such a strong adoption of Biochar use that there are no more control areas. In Kampong Chhnang, the use of Biochar starts to spread now.

6.7 Fuerzas/ ventajas/ oportunidades de la Tecnología

Fuerzas/ ventajas/ oportunidades desde la perspectiva del usuario de la tierra
Less insect damages where Biochar is applied.
Good growth of vegetables, with increased yields especially for onions.
The rice seedlings are stronger, and the roots break less while transplanting, and the plants recover quickly.
The plants survive a short dry spell better.

Fuerzas/ ventajas/ oportunidades desde la perspectiva del compilador o de otra persona de referencia clave
Soil amendment with long-term effect, as Biochar has a long half-life period.
Buffering and raising of the pH, especially in sandy soils.
Less washing out of nutrients.

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?
Substrate to make Biochar (rice husks) is difficult to find in the area in big amounts, as only small rice mills are working there.	Rice husks are wasted in other places. Networking with other villages. Use other (waste) sources of organic matter like leaves.
Increased workload for the Biochar production (compensated by the increased yields).	Use a bigger kiln to decrease the workload.

Debilidades/ desventajas/ riesgos desde la perspectiva del compilador o de otra persona de referencia clave	¿Cómo sobreponerse a ellas?
The energy produced during the pyrolysis is wasted.	Use it to power engines or as heating source. This would only be viable on large-scale kilns.

7.1 Métodos/ fuentes de información

7.2 Vínculos a las publicaciones disponibles

Título, autor, año, ISBN:

Ithaka Journal

¿Dónde se halla disponible? ¿Costo?

www.ithaka-institut.org

Título, autor, año, ISBN:

Biochar foundation

¿Dónde se halla disponible? ¿Costo?

www.britishbiocharfoundation.org