1.2 Coordonnées des personnes-ressources et des institutions impliquées dans l'évaluation et la documentation de la Technologie

Nom du projet qui a facilité la documentation/ l'évaluation de la Technologie (si pertinent)

Nom du ou des institutions qui ont facilité la documentation/ l'évaluation de la Technologie (si pertinent)

1.3 Conditions relatives à l'utilisation par WOCAT des données documentées

Le compilateur et la(les) personne(s) ressource(s) acceptent les conditions relatives à l'utilisation par WOCAT des données documentées:

Oui

2.1 Courte description de la Technologie

Définition de la Technologie:

Terraces with narrow beds, used for growing tea, coffee, and horticultural crops on hillsides cleared from forests.

2.2 Description détaillée de la Technologie

Description:

The terraces described in this case study from northern Thailand are found on hilly slopes with deep soils. The climate is humid and tropical, with 1,700-2,000 mm of rainfall annually. The main aim of the terraces is to facilitate cultivation of tea or coffee on sloping land: erosion control is secondary. Coffee and tea, as well as flowers and vegetables, are good alternatives to opium poppies - which it is government policy to eradicate.

Purpose of the Technology: After clearing natural and secondary forests by slash and burn, terraces are aligned by eye - and constructed by hoe. The width of the bed is 1.0-1.5 m depending on slope, though there are no specific technical guidelines. The length of each terrace can be up to 25 m. Down the slope, after every 3-4 terraces, there are lateral drainage channels, approximately 20-30 cm wide and 10 cm deep. Situated at the foot of a riser, each channel has a gradient of 0.5% or less. Excess water - some of which cascades over the terrace risers, with some draining through the soil - is discharged through these channels, generally to natural waterways. The risers are steep, with a slope of above 100%, and without a defined lip.

Establishment / maintenance activities and inputs: Natural grass cover develops on the risers: this is cut back by hand hoe or machete, or completely removed. The grass is often burned. After harvest (of annual crops), the land is left until immediately before the next rainy season. The terraces at this stage are covered by weeds and grasses. Land is then tilled by hoe. The weeds and grasses are removed and heaped in piles outside the cropped area. They are not composted or used for mulching - and here an opportunity is missed. Where soil fertility is a problem, chemical fertilizers are used. Maintenance includes building up/repairing of risers and levelling of terrace beds as required.

Natural / human environment: The technology was pioneered, and continues to be practiced, by refugee immigrants from China looking for new areas to start farming. These immigrants first came in the 1950s, and cultivated simply through slash and burn techniques. During the 1970s they visited relatives in Taiwan and brought back the idea of small terraces. Originally they settled illegally, but eventually they were given official permission to stay. However, official title deeds to their land have not yet been allocated.

2.3 Photos de la Technologie

2.5 Pays/ région/ lieux où la Technologie a été appliquée et qui sont couverts par cette évaluation

Pays:

Thaïlande

Région/ Etat/ Province:

ChiangMai

Autres spécifications du lieu:

Amphur Mae Fa Luang

Spécifiez la diffusion de la Technologie:

• répartie uniformément sur une zone

S'il n'existe pas d'informations exactes sur la superficie, indiquez les limites approximatives de la zone couverte:

• 1-10 km2

Commentaires:

Total area covered by the SLM Technology is 5 km2.

This practice has been done by tribal people such as E-kaw, Lahu, Lisu, Mien, Khin, Thai Yai, Haw Chinese, H'mong

Map

×

2.6 Date de mise en œuvre de la Technologie

Si l'année précise est inconnue, indiquez la date approximative: :

• il y a moins de 10 ans (récemment)

2.7 Introduction de la Technologie

Spécifiez comment la Technologie a été introduite: :

• grâce à l'innovation d'exploitants des terres

Commentaires (type de projet, etc.) :

Taiwan.

3.1 Principal(aux) objectif(s) de la Technologie

• améliorer la production
• réduire, prévenir, restaurer les terres dégradées
• créer un impact économique positif

3.2 Type(s) actuel(s) d'utilisation des terres, là où la Technologie est appliquée

Terres cultivées

• Cultures annuelles
• Cultures pérennes (non ligneuses)
• Plantations d’arbres ou de buissons

• vegetables, flowers

Plantations d'arbres et d'arbustes - Précisez les cultures:

• café, cultivé en plein champ
• thé

Nombre de période de croissance par an: :

• 2

Précisez:

Longest growing period in days: 150 Longest growing period from month to month: Dec - Apr

Commentaires:

Major land use problems (compiler’s opinion): - soil erosion on cultivated hillsides
- practical difficulties in tending tea, coffee, vegetables and flowers on sloping land: farming is much easier on levelled land
- Lacking of land ownership (The whole area is reserved forest.)
- Low price of agricultural produce.

Major land use problems (land users’ perception): 1. Lacking of land ownership. 2. Landusers do not have Thai citizenship; less than 20% have ID cards (not citizenship).
Forest: before SWC measures

3.4 Approvisionnement en eau

Approvisionnement en eau des terres sur lesquelles est appliquée la Technologie:

• pluvial

3.5 Groupe de GDT auquel appartient la Technologie

• mesures en travers de la pente
• dérivation et drainage de l'eau

3.6 Mesures de GDT constituant la Technologie

pratiques végétales

• V2: Herbes et plantes herbacées pérennes

structures physiques

• S1: Terrasses

Commentaires:

Main measures: structural measures

Secondary measures: vegetative measures

3.7 Principaux types de dégradation des terres traités par la Technologie

érosion hydrique des sols

• Wt: perte de la couche superficielle des sols (couche arable)/ érosion de surface

dégradation chimique des sols

• Cn: baisse de la fertilité des sols et réduction du niveau de matière organique (non causée par l’érosion)

dégradation hydrique

• Ha: aridification

Commentaires:

Main type of degradation addressed: Wt: loss of topsoil / surface erosion, Cn: fertility decline and reduced organic matter content, Ha: aridification

Main causes of degradation: deforestation / removal of natural vegetation (incl. forest fires), Lack of enforcement of legislation or authority

Secondary causes of degradation: other human induced causes (specify) (Agricultural activities), other natural causes (avalanches, volcanic eruptions, mud flows, highly susceptible natural resources, extreme topography, etc.) specify

3.8 Prévention, réduction de la dégradation ou réhabilitation des terres dégradées

Spécifiez l'objectif de la Technologie au regard de la dégradation des terres:

• prévenir la dégradation des terres

4.1 Dessin technique de la Technologie

Spécifications techniques (associées au dessin technique):

Layout of small level bench terraces. After every third or fourth terrace a lateral drainage channel is built. Later, protective grass cover is established on the risers (right).

Technical knowledge required for field staff / advisors: moderate

Technical knowledge required for land users: moderate

Main technical functions: control of dispersed runoff: retain / trap, reduction of slope angle, reduction of slope length

Secondary technical functions: control of concentrated runoff: impede / retard, increase of infiltration, increase / maintain water stored in soil

Vegetative measure: grass on risers (optional)
Vegetative material: G : grass

Vegetative measure: Vegetative material: G : grass

Vegetative measure: Vegetative material: G : grass

Vegetative measure: Vegetative material: G : grass

Terrace: bench level
Vertical interval between structures (m): 0.4
Spacing between structures (m): 0.3
Height of bunds/banks/others (m): 0.4
Width of bunds/banks/others (m): 1.5
Length of bunds/banks/others (m): 25

Structural measure: drainage channels
Depth of ditches/pits/dams (m): 0.1
Width of ditches/pits/dams (m): .02 - .3

Construction material (earth): It is the earth dug in situ.

Lateral gradient along the structure: 0%

Vegetation is used for stabilisation of structures.

Auteur:

Mats Gurtner

4.2 Informations générales sur le calcul des intrants et des coûts

autre/ monnaie nationale (précisez):

Baht

Indiquez le taux de change des USD en devise locale, le cas échéant (p.ex. 1 USD = 79.9 réal brésilien): 1 USD = :

37,0

4.3 Activités de mise en place/ d'établissement

4.4 Coûts et intrants nécessaires à la mise en place

Commentaires:

Duration of establishment phase: 12 month(s)

4.5 Activités d'entretien/ récurrentes

4.6 Coûts et intrants nécessaires aux activités d'entretien/ récurrentes (par an)

Commentaires:

Clearing of forest is not included in the cost calculations. This calculation is based on a typical slope of approximately 20%, with risers of 0.2 m in height and beds 1.0 m wide. Maintenance costs include basic land preparation (for annual crops) or weeding etc for perennial crops.

4.7 Facteurs les plus importants affectant les coûts

Décrivez les facteurs les plus importants affectant les coûts :

The slope factor affects most because it will require longer time to construct.

5.1 Climat

5.2 Topographie

Commentaires et précisions supplémentaires sur la topographie:

Slopes on average: Also steep (ranked 3)
Soil fertility: Low (ranked 1) and very low (ranked 2)
Soil drainage/infiltration: Medium (ranked 1, good drainage though being cleyey soil) and good (ranked 2)
Soil water storage capacity: Medium and low (both ranked 1)

5.3 Sols

5.6 Caractéristiques des exploitants des terres appliquant la Technologie

Indiquez toute autre caractéristique pertinente des exploitants des terres:

Population density: < 10 persons/km2
6% of the land users are rich and own 35% of the land.
24% of the land users are average wealthy and own 40% of the land.
60% of the land users are poor and own 20% of the land.
10% of the land users are poor and own 5% of the land.
Off-farm income specification: farmers spend much time as farm labourers on other farms or in food processing factories - and some have jobs at construction sites, for example road building
Level of mechanization: Manual work (ranked 1) and animal traction (ranked 2)
Market orientation: Commercial/market (ranked 1, tea, coffee, vegetable and flower production) and subsistence (ranked 2)

5.7 Superficie moyenne des terres utilisées par les exploitants des terres appliquant la Technologie

5.8 Propriété foncière, droits d’utilisation des terres et de l'eau

Propriété foncière:

• état

Droits d’utilisation des terres:

• individuel

• illegal (initially) (see Annex T3)

• illegal (initially) (see Annex T3)

6.1 Impacts sur site que la Technologie a montrés

Impacts socio-économiques

Production

Revenus et coûts

Autres impacts socio-économiques

Impacts socioculturels

Impacts écologiques

Cycle de l'eau/ ruissellement

Sols

Biodiversité: végétale, animale

6.2 Impacts hors site que la Technologie a montrés

6.4 Analyse coûts-bénéfices

Quels sont les bénéfices comparativement aux coûts de mise en place (du point de vue des exploitants des terres)?

Quels sont les bénéfices comparativement aux coûts d'entretien récurrents (du point de vue des exploitants des terres)?

6.5 Adoption de la Technologie

Si disponible, quantifiez (nombre de ménages et/ou superficie couverte):

500

De tous ceux qui ont adopté la Technologie, combien d'entre eux l'ont fait spontanément, à savoir sans recevoir aucune incitation matérielle, ou aucune rémunération? :

• 51-90%

Commentaires:

10% of land user families have adopted the Technology with external material support

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

Comments on acceptance with external material support: estimates

90% of land user families have adopted the Technology without any external material support

450 land user families have adopted the Technology without any external material support

Comments on spontaneous adoption: estimates

There is a little trend towards spontaneous adoption of the Technology

Comments on adoption trend: There is a little growing spontaneous adoption: for example in the Mae Salong area farmers accept these terraces increasingly, but fruit growers tend to prefer intermittent ‘orchard terraces’ - terraces spaced apart, with 5 m or more of undisturbed land in-between. The benches in this case are backward sloping.

6.7 Points forts/ avantages/ possibilités de la Technologie

6.8 Faiblesses/ inconvénients/ risques de la Technologie et moyens de les surmonter

7.1 Méthodes/ sources d'information

7.2 Références des publications disponibles

Titre, auteur, année, ISBN:

No references