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

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

Welthungerhilfe (Welthungerhilfe) - Tadjikistan

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

Quand les données ont-elles été compilées (sur le terrain)?

01/05/2011

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:

Reclamation and infilling of eroded gullies using barriers of willow branches and live mulberry cuttings to trap loess soil from surface water runoff.

2.2 Description détaillée de la Technologie

Description:

Due to many different factors and mechanisms, soil erosion is at an advanced stage in many of the hilly and mountainous parts of Tajikistan. After disrupting the soil cover in steep areas, starting the process of soil detachment and transportation water runoff gets concentrated into specific areas. As a result, rills develop on the steep areas, and eventually enlarge into gullies.

Purpose of the Technology: To address this problem, low cost barriers are constructed from flexible living branches of a sprouting variety of tree, such as willow. These branches are placed along the gulley at intervals of 3-10 metres, so that they slow down the flow of surface water and trap the sediment, thus eventually filling in the gulley over a period of several years.

Establishment / maintenance activities and inputs: The barriers are designed to slowly help infill eroded gullies by trapping the sediment from muddy surface water runoff. This helps prevent further erosion, increases the amount of land available for pasture, and reduces the risk of mud flows or floods further down the slope.
In gullies no wider than 1-2m, live cuttings from local tree varieties with a diameter of 3-5cm and 1 metre in length can be used to establish horizontal woven barriers across the gulley. The barriers are placed at 3-5m intervals along the gulley, starting at the base.
These barriers are constructed from cuttings that are woven in narrow sections with 5-6cm intervals between them. Enforcement and strengthening of these plugs can be achieved through the use of long branches of locally available mulberry. The height of the plug should not exceed 0.5m. The construction activities start in the spring and within several weeks some of the cuttings begin to sprout and grow. To avoid erosion at the sides of the structure, the cut offs are embedded into the sides of the gulley.

Natural / human environment: Gulley plugging is used in pasture land that suffers from overgrazing, deforestation and trampling, which has resulted in the degradation of the soil. Subsequently, the soil has become more vulnerable to the impact of heavy rain in the spring and autumn months, and is prone to erosion from surface water runoff.

2.3 Photos de la Technologie

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

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: :

• par le biais de projets/ d'interventions extérieures

Commentaires (type de projet, etc.) :

The technology was developed and promoted using the framework of EC TACIS funded Welthungerhilfe project in Khatlon

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

• réduire, prévenir, restaurer les terres dégradées

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

Commentaires:

Major land use problems (compiler’s opinion): Overgrazing on pasture lands, that leads to reduced vegetation cover and deforestation, contributes greatly to the causes of top soil erosion and gulley formation.

Major land use problems (land users’ perception): Gullies are formed after intensive rainfall events. There is nothing in place to stop this erosion.

Semi-nomadism / pastoralism: cows, goats. sheep

Grazingland comments: There is local grazing on this land, but some areas are subjected to nomadic grazing during the migration of livestock between the winter and summer pastures.

Future (final) land use (after implementation of SLM Technology): Mixed: Mf: Agroforestry

Type of grazing system comments: There is local grazing on this land, but some areas are subjected to nomadic grazing during the migration of livestock between the winter and summer pastures.

Si l'utilisation des terres a changé en raison de la mise en œuvre de la Technologie, indiquez l'utilisation des terres avant la mise en œuvre de la Technologie:

Grazing land: Ge: Extensive grazing land

3.3 Informations complémentaires sur l'utilisation des terres

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

• pluvial

Nombre de période de croissance par an: :

• 1

Précisez:

Longest growing period in days: 160Longest growing period from month to month: March - June

Densité d'élevage/ chargement (si pertinent):

1-10 LU /km2

3.4 Groupe de GDT auquel appartient la Technologie

• mesures en travers de la pente

3.5 Diffusion de la Technologie

Spécifiez la diffusion de la Technologie:

• répartie uniformément sur une zone

Si la Technologie est uniformément répartie sur une zone, indiquez la superficie couverte approximative:

• < 0,1 km2 (10 ha)

Commentaires:

Total area covered by the SLM Technology is 0.017 m2.

Approximately an 800 m long eroded gully was reclaimed.

3.6 Mesures de GDT constituant la Technologie

Commentaires:

Main measures: vegetative measures, structural measures

Type of vegetative measures: aligned: -linear

3.7 Principaux types de dégradation des terres traités par la Technologie

Commentaires:

Main type of degradation addressed: Wg: gully erosion / gullying

Main causes of degradation: deforestation / removal of natural vegetation (incl. forest fires) (Trees were cut from a steep slope on the side of the hillside.), overgrazing (Freely grazed area, carrying capacity less than animal numbers grazing.)

Secondary causes of degradation: Heavy / extreme rainfall (intensity/amounts) (More intensive rainfall.), land tenure (Lack of control of livestock grazing activities.), poverty / wealth, war and conflicts (Gullies appeared after civil war.)

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:

• restaurer/ réhabiliter des terres sévèrement dégradées

4.1 Dessin technique de la Technologie

4.2 Spécification/ explications techniques du dessin technique

For the plugging of the gully, a low cost and simple barrier was made from locally available fast sprouting species of trees; in this case live willow cuttings were used. In the gully a narrow section was selected, and cuttings (3-5 cm diameter, 1 m length) were placed in a line with 10 cm intervals in between. One third of the cuttings were planted in the gulley, and the rest were used to create a 'wave' wall of flexible branches, which was planted with local mulberry trees (1-1.5 cm diameter). The weaved branches have to be pushed down from the top to make the barrier suitably dense. The ends of the mulberry branches have to be stuck securely to the soil inside the gulley.

Location: Dorobi village. Khovaling / Khatlon / Tajikistan

Date: 2nd July, 2010

Technical knowledge required for field staff / advisors: moderate

Technical knowledge required for land users: moderate

Main technical functions: control of concentrated runoff: impede / retard, stabilisation of soil (eg by tree roots against land slides)

Secondary technical functions: improvement of ground cover, increase of surface roughness, sediment retention / trapping, sediment harvesting

Aligned: -linear
Vegetative material: T : trees / shrubs
Vertical interval within rows / strips / blocks (m): 0.2

Trees/ shrubs species: mulberry

Retention/infiltration ditch/pit, sediment/sand trap
Vertical interval between structures (m): 3-5
Depth of ditches/pits/dams (m): 0.5
Width of ditches/pits/dams (m): 1.5
Length of ditches/pits/dams (m): 0.5

Construction material (wood): Willow and mulberry branches

Vegetation is used for stabilisation of structures.

4.3 Informations générales sur le calcul des intrants et des coûts

autre/ monnaie nationale (précisez):

Tajik Somoni

Indiquer le taux de change du dollars en monnaie locale (si pertinent): 1 USD= :

4,5

4.4 Activités de mise en place/ d'établissement

	Activité	Type de mesures	Calendrier
1.	planting mulberry in willow wave structure	Végétale	spring
2.	establishment of barriers in gully bed	Structurel	once in the beginning

4.5 Coûts et intrants nécessaires à la mise en place

	Spécifiez les intrants	Unité	Quantité	Coûts par unité	Coût total par intrant	% du coût supporté par les exploitants des terres
Main d'œuvre	Planting mulberry	Persons/day	1,0	25,0	25,0	100,0
Main d'œuvre	Establishment of barriers in gully	Persons/day	1,0	25,0	25,0	100,0
Matériel végétal	Mulberry seedlings	Pieces	20,0	1,0	20,0	100,0
Matériaux de construction	Willow cuttings	Pieces	20,0	1,0	20,0	100,0
Coût total de mise en place de la Technologie					90,0

Commentaires:

Duration of establishment phase: 12 month(s)

4.6 Activités d'entretien/ récurrentes

	Activité	Type de mesures	Calendrier/ fréquence
1.	Reinforce structure with additional seedlings when needed	Végétale	annually
2.	establishment of additional barriers after filling existing barriers with sediments	Structurel	once per year in beginning of rainy season

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

	Spécifiez les intrants	Unité	Quantité	Coûts par unité	Coût total par intrant	% du coût supporté par les exploitants des terres
Main d'œuvre	Reinforce structure	Persons/day	1,0	25,0	25,0	100,0
Main d'œuvre	Establishment of additional barriers	Persons/day	1,0	25,0	25,0	100,0
Matériel végétal	Mulberry seedlings	Pieces	20,0	1,0	20,0	100,0
Matériaux de construction	Willow cuttings	Pieces	20,0	1,0	20,0	100,0
Coût total d'entretien de la Technologie					90,0

Commentaires:

The unit cost is for a gulley plug, 1.5 metre wide and around 1m in height.

4.8 Facteurs les plus importants affectant les coûts

Décrivez les facteurs les plus importants affectant les coûts :

The materials used to construct the gulley plug are locally available, and are therefore free of charge to the land user. The labour (or time in labour) is the most substantial cost, and this is directly proportional to the number of gulley plugs required to infill the entire eroded gulley. If there is a big sediment load in the surface water runoff it will back fill behind the gulley plugs rapidly and additional barriers will need to be established.

5.1 Climat

5.2 Topographie

Commentaires et précisions supplémentaires sur la topographie:

Altitudinal zone: 1257 m a.s.l.

Slopes on average: Average slope 12.6%, max slope 17.2%

5.3 Sols

Si disponible, joignez une description complète du sol ou précisez les informations disponibles, par ex., type de sol, pH/ acidité du sol, capacité d'échange cationique, azote, salinité, etc.

Soil texture = loess soil

Soil fertility is low due to over use and lack of fallow time.

Soil drainage / infiltration is poor

Soil water storage capacity is low

5.4 Disponibilité et qualité de l'eau

Commentaires et précisions supplémentaires sur la qualité et la quantité d'eau:

Availability of surface water: In the area around the gulley the land is compacted.

5.5 Biodiversité

5.6 Caractéristiques des exploitants des terres appliquant la Technologie

Indiquez toute autre caractéristique pertinente des exploitants des terres:

Land users applying the Technology are mainly common / average land users

Population density: 10-50 persons/km2

Annual population growth: 1% - 2%; 2%

20% of the land users are average wealthy.
80% of the land users are poor.

5.7 Superficie moyenne des terres détenues ou louées par les exploitants appliquant la Technologie

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

Propriété foncière:

• état

Droits d’utilisation des terres:

• loué

5.9 Accès aux services et aux infrastructures

6.1 Impacts sur site que la Technologie a montrés

Impacts socio-économiques

Production

Impacts socioculturels

Impacts écologiques

Cycle de l'eau/ ruissellement

Sols

Réduction des risques de catastrophe et des risques climatiques

6.2 Impacts hors site que la Technologie a montrés

6.3 Exposition et sensibilité de la Technologie aux changements progressifs et aux évènements extrêmes/catastrophes liés au climat (telles que perçues par les exploitants des terres)

Changements climatiques progressifs

Changements climatiques progressifs

	Saison	Type de changements/ extrêmes climatiques	Comment la Technologie fait-elle face à cela?
températures annuelles		augmente	pas connu

Extrêmes climatiques (catastrophes)

Catastrophes météorologiques

	Comment la Technologie fait-elle face à cela?
pluie torrentielle locale	bien
tempête de vent locale	pas connu

Catastrophes climatiques

	Comment la Technologie fait-elle face à cela?
sécheresse	pas bien

Catastrophes hydrologiques

	Comment la Technologie fait-elle face à cela?
inondation générale (rivière)	pas bien

Autres conséquences liées au climat

Autres conséquences liées au climat

	Comment la Technologie fait-elle face à cela?
réduction de la période de croissance	pas connu

Commentaires:

As a living barrier it needs to grow, and therefore it is sensitive to drought conditions.

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

• plus de 50%

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

10 households in an area of 1.7 ha

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

• 90-100%

Commentaires:

100% of land user families have adopted the Technology without any external material support

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

There is a little trend towards spontaneous adoption of the Technology

Comments on adoption trend: There is little trend towards (growing) spontaneous adoption of the technology.

6.7 Points forts/ avantages/ possibilités de la Technologie

Points forts/ avantages/ possibilités du point de vue de l'exploitant des terres
No training and additional skills are required. How can they be sustained / enhanced? Broad promotion to other communities with similar climatic conditions and similar issues.
It is low cost option.
Easy to establish, with a low workload.

Points forts/ avantages/ possibilités du point de vue du compilateur ou d'une autre personne ressource clé
Gulley plugs are relatively easy to construct and have a low initial outlay. How can they be sustained / enhanced? It could be further supported by the strong involvement of local authorities, through the organisation of cross visits, and disseminating ideas between farmers.
It is flexible as various varieties of local sprouting trees can be used to build the gulley plug.
It can prevent further erosion and expansion of the gulley. It can also increase the amount of land available for pasture activities.
Environmentally friendly

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

Faiblesses/ inconvénients/ risques du point de vue du compilateur ou d'une autre personne ressource clé	Comment peuvent-ils être surmontés?
The gulley plug is weak in the beginning as the mulberry trees become more established. It is more susceptible to the impact of heavy rainfall events and concentrated run off down the gulley.	High levels of maintenance in the first initial few seasons.
The gulley plug becomes less effective as the gullies become wider and deeper.	Fencing around the gulley.
The gulley plug has to be protected from livestock who will eat the vegetation.

7.2 Références des publications disponibles

Titre, auteur, année, ISBN:

Welthungerhilfe project final narrative report (144-912) - 2010

Disponible à partir d'où? Coût?

Welthungerhilfe projects in Khatlon region, Temurmalik district