Tecnologías

Shelterbelts for farmland in sandy areas [China]

Farmland shelter belt

technologies_1366 - China

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1. Información general

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

Persona(s) de referencia clave

Especialista MST:
Especialista MST:

Wang Dogmei

China

Nombre del proyecto que financió la documentación/ evaluación de la Tecnología (si fuera relevante)
Book project: where the land is greener - Case Studies and Analysis of Soil and Water Conservation Initiatives Worldwide (where the land is greener)
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

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

1.5 Referencia al (los) Cuestionario(s) de Enfoques MST (documentados usando WOCAT)

Shelter Belt
approaches

Shelter Belt [China]

The shelter belt is a strip or a row of trees planted in a farmland as a wind barrier to protect crops and reduce wind erosion.

  • Compilador: Meili WEN

2. Descripción de la Tecnología MST

2.1 Breve descripción de la Tecnología

Definición de la Tecnología:

Belts of trees, planted in a rectangular grid pattern or in strips within, and on the periphery of, farmland to act as windbreaks.

2.2 Descripción detallada de la Tecnología

Descripción:

Shelterbelts to protect cropland are a specific type of agroforestry system comprising certain tall growing tree species. Such shelterbelts around farmland help reduce natural hazards including sandstorms, wind erosion, shifting sand, droughts and frost. They also improve the microclimate (reduced temperature, wind speed, soil water loss and excessive wind-induced transpiration) and create more favourable conditions for crop production. Thus the establishment of shelterbelts plays a crucial role in the sandy drylands that are affected by wind and resultant desertification
especially during winter and spring. Where there is irrigation, the shelterbelts protect the infrastructure from silting-up with wind-borne sediment.
Strips of tall growing species (15-25 m) of poplar (Populus spp.) or willow (Salix spp.) were originally (from 1960s onwards) planted in a 400 by 600 m rectangular grid pattern within extensive areas of cropland, with an extra belt of windbreaks on the windward side (against the prevailing wind). Generally, the distance effectively protected is 15-25 times the tree height. Strips are of variable width, consisting of 2-5 tree lines (1-3 m apart) with trees planted every 1-2 m within the lines. Selective felling is used to maintain adequate growing space and the protective effect of the trees.
The impact of the shelterbelts depends on the planting pattern of the trees (the format of strips and grids), the orientation of the shelterbelts in relation to the wind, the spacing between, and the width of each strip and the type of trees planted. The specific design is primarily based on preventing the negative effects of wind, but depends also on local conditions such as the layout of the land, the location of the roads, farm boundaries and irrigation canals. Ideally the tree strips are perpendicular to the prevailing wind direction, and the angle between the strip and the prevailing wind is never less than 45 degrees. The structure of the strips determines the way the wind is controlled, ranging from blocking the wind
to letting it diffuse through semi-permeable shelterbelts. The best effect is achieved if the wind is not blocked entirely, as this can cause turbulence.
The ownership of the land and the shelterbelts still rests with the state, but management has been more and more transferred to individual households. On condition that the impact of the shelterbelt is not affected, the local forestry agencies now allow some felling of mature trees - on a rotational and selective basis, for timber and firewood. Pine trees (Pinus sylvestris var. mongolica and P. tabulaeformis), which command high value as timber for construction, and fruit (and cash) trees like the apricot tree (Prunus armeniace) are increasingly used.

2.3 Fotografías de la Tecnología

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

País:

China

Región/ Estado/ Provincia:

Inner Mongolia Autonomous Region

Especifique la difusión de la Tecnología:
  • distribuida parejamente sobre un área
Si la Tecnología se halla difundida homogéneamente a lo largo de un área, especifique el área que cubre (en km2):

500,0

Si se desconoce el área precisa, indique el área aproximada cubierta:
  • 100-1,000 km2
Comentarios:

Total area covered by the SLM Technology is 500 km2.

Total SWC Technology area is not clear. This technology area data is from Inner Mongolia forest department. Inner Mongolia autonomy region forest statistic data, 1987, P75. Technology beginning year is from: Water and soil conservation bureau, Yellow River irrigation works committee of Department of water and electricity. Water and soil conservation economy benefit thesis collecting,1987, P45-47.

2.6 Fecha de la implementación

Si no se conoce el año preciso, indique la fecha aproximada:
  • hace más de 50 años atrás (tradicional)

2.7 Introducción de la Tecnología

Especifique cómo se introdujo la Tecnología:
  • mediante proyectos/ intervenciones externas
Comentarios (tipo de proyecto, etc.):

USA and domestic.

3. Clasificación de la Tecnología MST

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

  • reducir el riesgo de desastres naturales
  • adaptarse al cambio climático/ extremos climáticos y sus impactos

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

Mezcla de tipos de uso de tierras dentro de la misma unidad de tierras: :

Especifique el uso combinado de tierras (cultivos/ pastoreo/ árboles):
  • Agroforestería

Tierras cultivadas

Tierras cultivadas

  • Cosecha anual
Cosechas anuales - Especifique cultivos:
  • cereales - maíz
  • wheat
Número de temporadas de cultivo por año:
  • 1
Especifique:

Longest growing period in days: 150Longest growing period from month to month: May - Sep

Bosques

Bosques

  • Bosques/ zonas boscosas (semi) naturales
  • Plantación de árboles, reforestación
Bosques/ zonas boscosas (semi-) naturales: Especifique tipo de manejo:
  • Tala selectiva
Tipo de árbol:
  • Especies de Pinus
  • Especies de Populus
  • Salix spp
Productos y servicios:
  • Madera
  • Leña
  • Frutos y nueces
  • Protección contra desastres naturales
Comentarios:

Trees/ shrubs species: Poplars (Populus spp.), willows (Salix spp.), increasingly also pine (Pinus sylvestris var. Mongolic

Major land use problems (compiler’s opinion): Strong winds in the winter and spring result in serious natural hazards including sand storms, sand encroachment and wind erosion, while dry and hot winds in the summer increase transpiration leading to plant stress and reduced crop yields.

Major land use problems (land users’ perception): Low yield and intensive wind blow in winter and spring.

3.3 ¿Cambió el uso de tierras debido a la implementación de la Tecnología?

¿Cambió el uso de tierras debido a la implementación de la Tecnología?
  • Sí (Por favor responda las preguntas de abajo referidas al uso de la tierra antes de implementar la Tecnología)
Tierras cultivadas

Tierras cultivadas

  • Cosecha anual

3.4 Provisión de agua

Provisión de agua para la tierra donde se aplica la Tecnología:
  • mixta de secano – irrigada

3.5 Grupo MST al que pertenece la Tecnología

  • agroforestería
  • rompevientos/ cinturones de protección

3.6 Medidas MST que componen la Tecnología

medidas vegetativas

medidas vegetativas

  • V1: Cubierta de árboles y arbustos
medidas de manejo

medidas de manejo

  • M1: Cambio de tipo de uso de la tierra
Comentarios:

Main measures: vegetative measures

Type of vegetative measures: aligned: -against wind

3.7 Principales tipos de degradación del suelo encarados con la Tecnología

erosión de suelos por viento

erosión de suelos por viento

  • Et: pérdida de capa arable
  • Eo; efectos de degradación fuera del sitio:
degradación del agua

degradación del agua

  • Ha: aridificación
Comentarios:

Main type of degradation addressed: Et: loss of topsoil, Eo: offsite degradation effects, Ha: aridification

Main causes of degradation: deforestation / removal of natural vegetation (incl. forest fires), poverty / wealth (Lack of captial)

Secondary causes of degradation: overgrazing, education, access to knowledge and support services (Lack of knowledge), Lack of enforcement of legislat./authority

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
Comentarios:

Main goals: mitigation / reduction of land degradation

4. Especificaciones técnicas, actividades de implementación, insumos y costos

4.1 Dibujo técnico de la Tecnología

Especificaciones técnicas (relacionadas al dibujo técnico):

Overview of the shelterbelt layout.
Insert 1: Planting scheme: shelterbelts compromise 2-5 tree lines forming the windbreak about 5-15 m wide and 15-25 m high.
Insert 2: Rectangle grid layout of shelterbelts. Spacing of the rows is denser against the prevailing wind.

Technical knowledge required for field staff / advisors: moderate

Technical knowledge required for land users: low

Main technical functions: increase / maintain water stored in soil, reduction in wind speed, protection from wind erosion, protection from sand encroachment, protection of crops from mechanical damage, reduction in evaporation loss

Secondary technical functions: increase in organic matter

Aligned: -against wind
Vegetative material: T : trees / shrubs

Trees/ shrubs species: Poplars (Populus spp.), willows (Salix spp.), increasingly also pine (Pinus sylvestris var. Mongolic)

Autor:

Mats Gurtner

4.2 Información general sobre el cálculo de insumos y costos

Especifique cómo se calcularon los costos e insumos:
  • por área de Tecnología
Indique tamaño y unidad de área:

ha

Especifique la moneda usada para calcular costos:
  • USD
Indique el costo promedio del salario de trabajo contratado por día:

1.20

4.3 Actividades de establecimiento

Actividad Momento (estación)
1. 1 Planning / designing of shelterbelt.
2. 2 Selection and collection of trees seedlings.
3. 3 Clearing and preparing land for planting of shelterbelt in late autumn and spring
4. 3 Clearing and preparing land for planting of shelterbelt in
5. 4 Pits for planting the seedlings are dug 4 Pits for planting the seedlings are dug
6. 5 Tree seedlings are planted late spring
7. 6 After planting each seedling is watered for up to two years.

4.4 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 Mainly collection and planting ha 79,0 1,2 94,8
Equipo tools ha 1,0 5,0 5,0 100,0
Material para plantas tree seedlings ha 1,0 25,0 25,0
Costos totales para establecer la Tecnología 124,8
Costos totales para establecer la Tecnología en USD 124,8
Si el usuario de la tierra no cubrió el 100% de los costos, indique quién financió el resto del costo:

USA and domestic projects

Comentarios:

Duration of establishment phase: 36 month(s)

4.5 Actividades de establecimiento/ recurrentes

Actividad Momento/ frequencia
1. Watering after planting /timely
2. Pruning of trees.
3. Pest and disease control within shelterbelt.
4. Intermediate/ selective tree felling.

4.6 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 Watering and Pruning ha 7,0 1,2 8,4 100,0
Material para plantas tree seedling ha 1,0 3,0 3,0 100,0
Indique los costos totales para mantenecer la Tecnología 11,4
Costos totales para mantener la Tecnología en USD 11,4
Comentarios:

The costs are calculated according to current standards/costs. The original planting is paid for by the state: replanting
and maintenance are the responsibility of the land user. If pines are the species of choice for re-planting, the cost
is considerably more than that shown above (which relates to poplar and willow).
Assuming: shelterbelts of 600 m by 400 m; each strip has 5 lines of trees (3 m apart), 2 m between trees within lines: resulting in 104 trees/ha, including the cropland between the strips (density within strips is 1666 trees/ha). Labour for establishment (104 trees): Land preparation, planting 10 days and 15 days for watering, weeding, etc (for first 3 years).

4.7 Factores más determinantes que afectan los costos:

Describa los factores más determinantes que afectan los costos:

The most important factors to affect the costs are seedlings (No.) and machine.

5. Entorno natural y humano

5.1 Clima

Lluvia anual
  • < 250 mm
  • 251-500 mm
  • 501-750 mm
  • 751-1,000 mm
  • 1,001-1,500 mm
  • 1,501-2,000 mm
  • 2,001-3,000 mm
  • 3,001-4,000 mm
  • > 4,000 mm
Especifique el promedio anual de lluvia (si lo conoce), en mm:

430,00

Zona agroclimática
  • semi-árida

5.2 Topografía

Pendientes en promedio:
  • plana (0-2 %)
  • ligera (3-5%)
  • moderada (6-10%)
  • ondulada (11-15%)
  • accidentada (16-30%)
  • empinada (31-60%)
  • muy empinada (>60%)
Formaciones telúricas:
  • meseta/ planicies
  • cordilleras
  • laderas montañosas
  • laderas de cerro
  • pies de monte
  • fondo del valle
Zona altitudinal:
  • 0-100 m s.n.m.
  • 101-500 m s.n.m.
  • 501-1,000 m s.n.m
  • 1,001-1,500 m s.n.m
  • 1,501-2,000 m s.n.m
  • 2,001-2,500 m s.n.m
  • 2,501-3,000 m s.n.m
  • 3,001-4,000 m s.n.m
  • > 4,000 m s.n.m
Indique si la Tecnología se aplica específicamente en:
  • no relevante

5.3 Suelos

Profundidad promedio del suelo:
  • muy superficial (0-20 cm)
  • superficial (21-50 cm)
  • moderadamente profunda (51-80 cm)
  • profunda (81-120 cm)
  • muy profunda (>120 cm)
Textura del suelo (capa arable):
  • áspera/ ligera (arenosa)
Materia orgánica de capa arable:
  • media (1-3%)
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

Soil water storage capacity: medium

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

Orientación del mercado del sistema de producción:
  • mixta (subsistencia/ comercial)
Ingresos no agrarios:
  • 10-50% de todo el ingreso
Nivel relativo de riqueza:
  • promedio
Nivel de mecanización:
  • mecanizado/motorizado
Indique otras características relevantes de los usuarios de las tierras:

Population density: 10-50 persons/km2

Annual population growth: 1% - 2%

80% of the land users are average wealthy and own 35% of the land.

Off-farm income specification: farmers benefit from the shelterbelts as a source of off-farm income, through fodder, timber and firewood

5.7 Área promedio de la tierra usada por usuarios de tierra que aplican la Tecnología

  • < 0.5 ha
  • 0.5-1 ha
  • 1-2 ha
  • 2-5 ha
  • 5-15 ha
  • 15-50 ha
  • 50-100 ha
  • 100-500 ha
  • 500-1,000 ha
  • 1,000-10,000 ha
  • > 10,000 ha

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

  • communal/state
  • individual (see Annex T3 for remark)
  • individual (see Annex T3 for remark)

6. Impactos y comentarios para concluir

6.1 Impactos in situ demostrados por la Tecnología

Impactos socioeconómicos

Producción

producción de cultivo

disminuyó
incrementó

producción de madera

disminuyó
incrementó

área de producción

disminuyó
incrementó
Comentarios/ especifique:

width of the shelterbelt

Ingreso y costos

ingreso agrario

disminuyó
incrementó
Otros impactos socioeconómicos

off-farm income

decreased
increased
Comentarios/ especifique:

extra timber and firewood

Crop production

decreased
increased
Comentarios/ especifique:

Trees in competition with crops for solar radiation, fertilizer, and water

Impactos socioculturales

mitigación de conflicto

empeoró
mejoró

Loss of Food per agricultural land

increased
decreased
Comentarios/ especifique:

shelterbelts of trees are not a direct source of food

Impactos ecológicos

Ciclo de agua/ escurrimiento de sedimento

escurrimiento superficial

incrementó
disminuyó
Cantidad antes de MST:

8

Cantidad luego de MST:

0

Suelo

humedad del suelo

disminuyó
incrementó

cubierta del suelo

disminuyó
mejoró

pérdida de suelo

incrementó
disminuyó
Cantidad antes de MST:

4

Cantidad luego de MST:

2

Reducción de riesgos de desastres y riesgos climáticos

velocidad de viento

incrementó
disminuyó
Otros impactos ecológicos

sand encroachment

improved
reduced

microclimate for crops

reduced
improved
Comentarios/ especifique:

regulating temperature, increasing humidity

conservation/maintenance of soil fertility

reduced
improved

6.4 Análisis costo-beneficio

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

ligeramente positivo

Ingresos a largo plazo:

muy positivo

6.5 Adopción de la Tecnología

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

40 households in an area of 100-1000km^2 (10-50 persons/km^2)

De todos quienes adoptaron la Tecnología, ¿cuántos lo hicieron espontáneamente, por ej. sin recibir nada de incentivos/ materiales:
  • 0-10%
Comentarios:

100% of land user families have adopted the Technology with external material support

40 land user families have adopted the Technology with external material support

Comments on acceptance with external material support: estimates

Comments on spontaneous adoption: estimates

There is no trend towards spontaneous adoption of the Technology

Comments on adoption trend: The technology has not spontaneously spread beyond the areas developed through government intervention.

6.7 Fuerzas/ ventajas/ oportunidades de la Tecnología

Fuerzas/ ventajas/ oportunidades desde la perspectiva del compilador o de otra persona de referencia clave
Reduced wind speed and trapped wind-blown sand particle

How can they be sustained / enhanced? Combine deciduous and evergreen trees to maintain shelterbelt’s protective function throughtout the year.
Increased crop yield

How can they be sustained / enhanced? Extend shelterbelt technology to unprotected croplands.
Increased cash income

How can they be sustained / enhanced? Improve rotational felling regimes that maximise quantity and quality of tree products (timber; fruit etc) without reducing the shelterbelt’s protective function. In Inner Mongolia apricot (Prunus armeniaca) and sea buckthorn (Hippophae rhamnoides) and in Gansu Province the Chinese dates (Ziziphus jujuba) are increasingly used.
Apart from their effect on the wind, the overall benefits of the shelterbelts - for timber, firewood, fruits and fodder for animals - outweigh the loss of cropland occupied by trees

How can they be sustained / enhanced? Experience over 40 years has demonstrated that narrower trees strips and smaller grid size (100 by 200 m) would increase ecological efficiency, but due to higher costs and potential competition with crops, the spacing of the shelterbelts has mostly remained as it was originally.
From 1960 onwards, approximately 22 million hectares – of vulnerable cropland have been protected in eastern Inner Mongolia

Editors’ comments: In China, a total of 1.84 million km2 suffer from desertification related to sand storms, shifting sands and wind erosion, making up 19% of the total land area. In those dry and desertified zones, farmland is barely productive, even with irrigation. The construction of shelterbelts in this northeastern part of China has had multiple benefits that outweigh the loss of cropland. However, maintenance has become an important issue with the changes in China’s land use laws. This is one of two examples of windbreaks amongst the case studies in this book. Remark: In the 1960s, all land ownership and land use rights in China were communal and cropland was farmed collectively by village communes. After reform and open policy was put into practice in 1978, land use rights were transferred to the villages, to groups and individuals. Land itself and the shelterbelts however still belonged to the state. Nowadays the rights to cultivate specific parcels of land, within protected blocks, are generally granted to individual farm households. In some cases, in recent years, the shelterbelts too have been redistributed to individuals to look after. Inevitably maintenance has become an issue. But most of the shelterbelts are managed well. 3.2.8: If farmer cuts mature timber (for example a 40 year-old poplar), he/she can sell it for US$ 20–25 per tree. With maturity of shelterbelts, the timber production increases, which brings increasing economic benefits; meanwhile, the effect of protection from wind erosion also improves.

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?
Loss of land due to area used for the shelterbelts In this wind-prone part of Inner Mongolia, overall gains from the protected zones compensate for the reduced area under crops, especially if economically valuable species are planted in the shelterbelt, such as Caragana korshinskii, which can be used as forage, for 'green fertilizer' through leaf mulch and for firewood.
Competition for sunshine, fertilizer and water Pruning of branches and digging of ditches to prevent roots penetrating the adjacent cropland
Farmers lost the right to crop the tree-occupied land (since the shelterbelts belonged to the state). Originally, farmers were not allowed to fell trees Nowadays the local forestry department permits farmers to occasionally cut trees, which is a source of income. If land users were allowed to cut trees on a more systematic basis, it would help them to better appreciate the benefits.
High cost (labour and money) for establishment Government support required.
Shelterbelts comprised of single tree species are less resistant to pests and diseases

Shelterbelts consume more water
Combine trees and shrubs/ different species, which improves both resistance and also the protective effect.

But they also help in drainage (where this is a problem) through lowering the ground water table and simultaneously reducing salinity. Appropriate tree species need to be selected and bred.

7. Referencias y vínculos

7.1 Métodos/ fuentes de información

7.2 Vínculos a las publicaciones disponibles

Título, autor, año, ISBN:

China atlas. China atlas publishing house, P 52.. 1999.

¿Dónde se halla disponible? ¿Costo?

library of Department of Resource and Environmental Science, BNU.

Título, autor, año, ISBN:

Zhao Yu, Jing Zhengping, Shi Peijun, Hao Yunchong et al. Inner Mongolia soil erosion research remote sensing was used in Inner Mongolia soil erosion research, Science publishing house, P25.. 1989.

¿Dónde se halla disponible? ¿Costo?

library of Department of Resource and Environmental Science, BNU.

Título, autor, año, ISBN:

Inner Mongolia forest department, Forest work manual,12, P33-34, P67.. 1998.

¿Dónde se halla disponible? ¿Costo?

library of Department of Resource and Environmental Science, BNU.

Título, autor, año, ISBN:

Synthesized investigate team in Inner Mongolia-Ningxia, CAS. West of northeast Forest in Inner Mongolia autonomy region, Science publishing house, P82-101.. 1981.

¿Dónde se halla disponible? ¿Costo?

library of Department of Resource and Environmental Science, BNU.

Título, autor, año, ISBN:

Sun Jinzhu. Natural condition and reconstruct in Hetao plain, Inner Mongolia people' s publishing house, P188-189.. 1976.

¿Dónde se halla disponible? ¿Costo?

library of Department of Resource and Environmental Science, BNU.

Título, autor, año, ISBN:

Inner Mongolia forest Department. Inner Mongolia autonomy region forest statistic data,P75.. 1987.

¿Dónde se halla disponible? ¿Costo?

library of Department of Resource and Environmental Science, BNU.

Título, autor, año, ISBN:

Hu Chun(chief editor). Inner Mongolia autonomy region climate resources about agriculture, forest and animal husbandry, Inner Mongolia people's publishing house, P45-47.. 1984.

¿Dónde se halla disponible? ¿Costo?

library of Department of Resource and Environmental Science, BNU.

Título, autor, año, ISBN:

Water and soil conservation bureau, Yellow River irrigation works committee of Department of water and electricity. Water and soil conservation economy benefit thesis collecting, P45-47.. 1987.

¿Dónde se halla disponible? ¿Costo?

library of Department of Resource and Environmental Science, BNU.

Título, autor, año, ISBN:

Zhang Pangchuen, A study on the benefit of shelter belt in the south part of Kerqin sand to agriculture increase in production. Journal of arid land resource and environment. Vol.4, no.1, P11-87.. 1990.

¿Dónde se halla disponible? ¿Costo?

library of Department of Resource and Environmental Science, BNU.

Título, autor, año, ISBN:

Sun Jinzhu,Chen Shan(chief editor). Inner Mongolia environment alarm beforehand and repair countermeasure. Inner Mongolia people's publishing house, P132.. 1994.

¿Dónde se halla disponible? ¿Costo?

library of Department of Resource and Environmental Science, BNU.

Título, autor, año, ISBN:

Compilation Committee of Inner Mongolia Forest Inner Mongolia Forest, Beijing: China Forestry Publishing House, 1989,299–319. 1989.

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