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)

ISRIC World Soil Information (ISRIC World Soil Information) - Países Bajos

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

Department of Resources and Environmental Science, Beijing Normal University (Department of Resources and Environmental Science, Beijing Normal University) - China

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

GEF/OP12 Gansu Project (GEF/OP12 Gansu Project) - China

1.3 Condiciones referidas al uso de datos documentados mediante WOCAT

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

01/03/2006

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:

Level bench terraces on the Loess Plateau, converting eroded and degraded sloping land into a series of steps suitable for cultivation.

2.2 Descripción detallada de la Tecnología

Descripción:

The Loess Plateau in north-central China is characterised by very deep loess parent material (up to 200 m), that is highly erodible and the source of most of the sediment in the lower reaches of the Yellow River.
The plateau is highly dissected by deep gullied valleys and gorges. The steep slopes, occupying 30-40% of the plateau area, have been heavily degraded by severe top soil and gully erosion. Over the whole Loess Plateau approximately 73,350 km2 of these erosion prone slopes have been conserved by terraces.
In the case study area (Zhuanglang County) the land that is suitable for terracing has been completely covered. The total terraced area is 1,088 km2, accounting for 90% of the hillsides. The terraces were constructed manually, starting at the bottom of the slopes and proceeding from valley to the ridge. The terraces comprise a riser of earth, with vertical or steeply sloping sides and an approximately flat bed (level bench). Depending on farmers preference some terrace beds are edged by a raised lip (a small earth ridge) which retains rainwater, others remain without lip. The semi-arid climate does not require a drainage system. For typical hillside terraces on slopes of 25-35% the bed width is about 3.5-5 metres with a 1-2 metre riser, involving moving about 2,000-2,500 cubic metres of soil (see table of technical specifications). Generally the risers are not specifically protected, but there may be some natural grasses growing on the upper part. The lower part of the riser is cut vertically into the original soil surface, and has no grass cover, being dry and compact. However it is not erosion-prone since it has a stable structure.
Over most of the Loess Plateau, the soil is very deep and therefore well suited to terrace construction. In addition to downstream benefits, the purpose is to create a better environment for crop production through improved moisture conservation, and improved ease of farming operations. In an average rainfall year, crop yields on terraced land are more than three times higher than they used to be on unterraced, sloping land. The implication is that terrace construction - though labour intensive - pays back in only three to four years when combined with agronomic improvements (such as applying farm yard manure and planting green manure). Some farmers try to make the best use of the upper part of terrace risers by planting cash trees or forage crops - including Hippophae rhamnoides (seabuckthorn), Caragana korshinskii (peashrub) and some leguminous grass. This is locally termed ‘terrace bund economy’. The plants stabilise the risers and at the same time provides extra benefits.

2.3 Fotografías de la Tecnología

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

2.7 Introducción de la Tecnología

Especifique cómo se introdujo la Tecnología:

• mediante proyectos/ intervenciones externas

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

Comentarios:

Major land use problems (compiler’s opinion): Cultivation of unterraced hillside slopes leads to serious soil erosion and problems of downstream sedimentation.
Loss of topsoil and rainwater in uncontrolled runoff has contributed to declining crop yields.

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:

• 1

Especifique:

Longest growing period in days: 160Longest growing period from month to month: May to September

3.4 Grupo MST al que pertenece la Tecnología

• medida de pendiente transversal

• terraces

3.5 Difusión de la Tecnología

Comentarios:

Total area covered by the SLM Technology is 1080 m2.

3.6 Medidas MST que componen la Tecnología

Comentarios:

Main measures: structural measures

3.7 Principales tipos de degradación del suelo encarados con la Tecnología

Comentarios:

Main type of degradation addressed: Wt: loss of topsoil / surface erosion, Wg: gully erosion / gullying, Wo: offsite degradation effects, Cn: fertility decline and reduced organic matter content, Ha: aridification

Main causes of degradation: soil management (Absence or bad maintenance of erosion control measures), other human induced causes (specify), poverty / wealth (Lack of captial), education, access to knowledge and support services (Lack of knowledge)

Secondary causes of degradation: labour availability (Lack of labour)

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:

• restaurar/ rehabilitar tierra severamente degradada

Comentarios:

Main goals: rehabilitation / reclamation of denuded land

4.1 Dibujo técnico de la Tecnología

4.2 Especificaciones técnicas/ explicaciones del dibujo técnico

Layout of level bench terraces on the Loess Plateau: the lower, vertical section is cut into the compacted soil. Natural grasses -
or planted grass/ shrub species - protect the more erodible and less steep upper part of the riser. The low ‘lip’ is optional.

Technical knowledge required for field staff / advisors: high

Technical knowledge required for land users: low

Main technical functions: reduction of slope angle, reduction of slope length, increase of infiltration, increase / maintain water stored in soil, water harvesting / increase water supply, retains runoff in-situ, reduces downstream flooding, reduces sediment deposition (a national/regional concern)

Structural measure: level bench terraces
Height of bunds/banks/others (m): 1-2
Width of bunds/banks/others (m): 3.5-5

Construction material (earth): loess parent material

Slope (which determines the spacing indicated above): 30%

4.3 Información general sobre el cálculo de insumos y costos

Especifique cómo se calcularon los costos e insumos:

• por área de Tecnología

Especifique la moneda usada para calcular costos:

• dólares americanos

4.4 Actividades de establecimiento

	Actividad	Tipo de medida	Momento
1.	Contour lines are marked out using pegs to show the location for the base of each terrace wall	Estructurales	-
2.	A trench is dug out along the marked line to serve as the foundation	Estructurales
3.	A trench is dug out along the marked line to serve as the foundation	Estructurales	-
4.	The topsoil between the pegged lines is removed and put aside	Estructurales
5.	See Annex T3: alternative ways of constructing the wall/riser, bed	Estructurales
6.	The wall is raised slightly higher to form a lip to retain rainwater on the	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	Voluntary and paid (building terraces)	ha	1,0	1200,0	1200,0	97,0
Mano de obra	survey of labour	ha	1,0	60,0	60,0
Equipo	tools	ha	1,0	30,0	30,0	100,0
Material de construcción	earth	ha	1,0
Costos totales para establecer la Tecnología					1290,0

Comentarios:

Duration of establishment phase: 4 month(s)

4.6 Actividades de establecimiento/ recurrentes

	Actividad	Tipo de medida	Momento/ frequencia
1.	1. Repairing any collapses in the terrace wall – often caused by heavy	Estructurales
2.	2. Re-levelling of the terraces where necessary. This work is usually done by hand, using shovels and two-wheel carts.	Estructurales

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	Reparing terraces	ha	1,0	25,0	25,0	97,0
Equipo	tools	ha	1,0	10,0	10,0
Material de construcción	earth	ha	1,0
Indique los costos totales para mantenecer la Tecnología					35,0

Comentarios:

Calculations above are based on the following situation: slopes of about 25-35%, bed width of 3.5-6 m, and a 1-2 m high riser, involving moving about 2,000-2,500 cubic metres of soil. Note: these calculations are based on several years experience in Zhuanglang: that is why they differ in some respects from the standardised table in 2.4.1.

5.1 Clima

5.2 Topografía

Indique si la Tecnología se aplica específicamente en:

• no relevante

Comentarios y especificaciones adicionales sobre topografía :

Slopes on average: also rolling
Altitudinal zone: 501- 2000 m a.s.l.
Landforms: Also ridges

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 fertility: low-medium
Soil drainage / infiltration: good

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

Indique otras características relevantes de los usuarios de las tierras:

Off-farm income specification: working in construction, temporary employments
Market orientation mixed (subsistence and commercial): ash crop (peas) and food crops (potatoes, wheat, maize, millet, sorghum)

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:

• estado

Derechos de uso de tierra:

• individual

6.1 Impactos in situ demostrados por la Tecnología

Impactos socioeconómicos

Producción

Ingreso y costos

Otros impactos socioeconómicos

Impactos socioculturales

Impactos ecológicos

Suelo

6.2 Impactos fuera del sitio demostrados por la Tecnología

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

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

NA

Comentarios:

There is no trend towards spontaneous adoption of the Technology

Comments on adoption trend: - The technology was implemented on a large scale through government initiated mass campaigns.
- The technology has generally not spontaneously spread beyond the areas developed through government intervention: the area that is suitable for terracing has been covered.
- Uncertainty over future land use rights limits the willingness of households to meet the costs of terrace construction.

6.7 Fuerzas/ ventajas/ oportunidades de la Tecnología

Fuerzas/ ventajas/ oportunidades desde la perspectiva del usuario de la tierra
Diversification of production: terracing makes cultivation of new cash crops possible: flax (for linseed oil), pears, apples, apricots, water melon; all these give high returns and thus make terrace construction profitable.
Benefits pay back the investments after only three to four years; approx. calculated on the basis of US$ 450 extra income per annum per hectare (for wheat) vs US$ 1,200 labour investment per hectare.

Fuerzas/ ventajas/ oportunidades desde la perspectiva del compilador o de otra persona de referencia clave
Reduced erosion, reduced loss of rainwater through runoff (increased in water use efficiency) and reduced fertility loss due to reduced slope angle and length How can they be sustained / enhanced? Maintain the quality of terrace construction.
Increased soil moisture How can they be sustained / enhanced? Construct/maintain a terrace lip to retain rainwater on the terrace
Increased crop production (before 1983 hunger and starvation in the area) How can they be sustained / enhanced? Combine with improved crop husbandry.
Easier field operations: the level terrace is easier to cultivate than the original hill slope.
Improvements of farmers’ living standard and decline in poverty stricken population.

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

Debilidades/ desventajas/ riesgos desde la perspectiva del compilador o de otra persona de referencia clave	¿Cómo sobreponerse a ellas?
Terrace riser can be destroyed by storms – and, sometimes, rodent holes	Good and timely repair and maintenance: planting upper parts of the risers with grass, bushes or even trees help to stabilise the risers but can lead to competition with the crop for water.
High cost/input for construction and establishment	Given the high erodibility of the soil and the steep slopes there is no real alternatives to labour-intensive terracing.
High loss of soil moisture due to evaporation from the soil surface. Wind erosion due to tillage	Protect soil surface for example by conservation agriculture – comprising permanent cover, crop rotation, reduced tillage – could be supplementary agronomic and vegetative options.
Decrease in production in first year	Apply manure and fertilizer.

7.2 Vínculos a las publicaciones disponibles

Título, autor, año, ISBN:

Terraces In China. Published By Ministry Of Water Resources Beijing, PRC.. 1989.

Título, autor, año, ISBN:

Conservancy engineering budgetary estimateration. Issued by Ministry of water resources of PRC, Published by Yellow-river water conservancy publishing company, Zhengzhou, PRC. 2003.

Título, autor, año, ISBN:

A Great Cause for Centuries – 50 Years in Water and Soil Conservation in China. Published by Department of Soil and Water Conservation, Ministry ofWater Resources Beijing, PRC. 2000.

Título, autor, año, ISBN:

Dongyinglin, Changpiguang, Wangzhihua: Discussion on several questions onincreasing production of the terrace with two banks; Soil and Water Conservation Science and Technology in Shanxi. No. 1, p 36–37. 1990.

Título, autor, año, ISBN:

Liumingquan, Zhangaiqin, Liyouhua:Pattern engineering of reconstruction the slope cropland; Soil and Water Conservation Science and Technology in Shanxi,No. 3, p 18–21. 1992.

Título, autor, año, ISBN:

Liangqichun, Changfushuang, Liming: A study on drawing up budgetary estimate quota of terraced field; Bulletin of Soil andWater Conservation, Vol. 21, No. 5, p 41–44. 2001.

Título, autor, año, ISBN:

Lixuelian, Qiaojiping: Synthetic technology of fertilizing and improving production on the newterrace. Terraces in China. Soil and Water Conservation Science and Technology in Shanxi, No. 3, p 13–14. 1998.