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)

The Transboundary Agro-ecosystem Management Project for the Kagera River Basin (GEF-FAO / Kagera TAMP )

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

Food and Agriculture Organization of the United Nations (FAO) - Italie

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

Rwanda Agriculture Board (Rwanda Agriculture Board) - Rwanda

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:

Locally referred to as ‘radical terracing’, the method involves earth moving operations that create reverse-slope bench terraces which have properly shaped risers stabilized with grass or trees on embankment to avoid collapse.

2.2 Description détaillée de la Technologie

Description:

In Rwanda, a unique method of back-slope terracing originally introduced by missionaries growing wheat in the Northern Province in the 1970s, has been widely adopted by smallholder farmers in many parts of the country. The farmers are careful to isolate the topsoil, then they re-work the subsoil to create the required reverse-slope bench, after which the topsoil is spread over the surface. The riser is planted with short runner grass for stabilization, all within the same day. Radical terracing is usually done manually with hoes and shovels, mostly by communal group-work involving hundreds of farmers (see left photo). Thus, a hillside can be terraced in one day. Where radical terraces have been constructed, the effects have been dramatic, achieving optimum water and soil conservation on slopes exceeding 50%, while adoption rates have been quite extensive. This high adoption of radical terracing is related to the existing policies and programs such as land consolidation, land management and crop intensification programs. These policies/programs boost the use of radical terraces by providing farmers more opportunities to easily access inputs such as improved seeds and manure for increasing the productivity of constructed radical terraces. Recent studies (e.g. Fleskens, 2007, Bizoza and de Graaff 2012 and Kagabo et al. 2013) assert that radical terraces in the highlands of Rwanda are only financially viable when the opportunity cost of labour and manure are below the local market price levels and when agriculture area on these radical terraces can be substantially intensified. Ten to 30 metric tons of manure (organic) are required to restore the soil fertility of newly established radical terraces.

Purpose of the Technology: In Rwanda, radical terraces are principally designed (1) to reduce soil losses through enhanced retention and infiltration of runoff, (2) to promote permanent agriculture on steep slopes and (3) to promote land consolidation and intensive land use.

Establishment / maintenance activities and inputs: Newly established radical terraces should be protected at their risers and outlets, especially in the first or second year of the establishment. After establishing a terrace, a riser is shaped and grasses or shrubs/trees are planted soon after. Napier grass is commonly planted and is used as forage for livestock. Risers on radical terraces are seen as a new production niche of forage as a result of land shortage and a strict zero grazing policy.

Natural / human environment: Radical terraces have the potential of improving farmers’ livelihoods and increasing the resilience of a degraded environment.

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

• Government

Commentaires (type de projet, etc.) :

The Government introduced it through local leaders and agronomist. It was established in 2004

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): Soil erosion due to high runoff on the steep slopes, deforestation, intensive cultivation and lack of suitable land management methods.

Major land use problems (land users’ perception): Low crop production, soil erosion and lack of fodder

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: :

• 2

Précisez:

Longest growing period in days: 120; Longest growing period from month to month: September- January; Second longest growing period in days: 90; Second longest growing period from month to month: March - June

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

Commentaires:

Total area covered by the SLM Technology is 10.3 km2.

3.6 Mesures de GDT constituant la Technologie

Commentaires:

Type of vegetative measures: aligned: -contour

3.7 Principaux types de dégradation des terres traités par la Technologie

Commentaires:

Secondary types of degradation addressed: Wo: offsite degradation effects

Main causes of degradation: over-exploitation of vegetation for domestic use, overgrazing (Grazing and fodder), other natural causes (avalanches, volcanic eruptions, mud flows, highly susceptible natural resources, extreme topography, etc.) specify (Extreme topography: steep slopes in many cases over 50%), population pressure (High density (in rural area over 400 inhabitant per ha))

Secondary causes of degradation: deforestation / removal of natural vegetation (incl. forest fires) (Use of cooking energy (fire wood)), poverty / wealth (Farmers have low income and have less access to off farm income or remittances), education, access to knowledge and support services (High rate of irriteracy)

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:

• réduire la dégradation des terres

Commentaires:

Secondary goals: prevention of land degradation, rehabilitation / reclamation of denuded land

4.1 Dessin technique de la Technologie

4.2 Spécification/ explications techniques du dessin technique

The farmers are careful to isolate the topsoil, then they re-work the subsoil to create the required reverse-slope bench, after which the topsoil is spread over the surface. The riser is planted with short runner grass for stabilization, all within the same period.

Location: Nyamirama. Kayonza/West/Rwanda

Date: 2013

Technical knowledge required for field staff / advisors: high (Special training should be provided to field staff to be able to make an adequate design)

Technical knowledge required for land users: moderate (Land users are required to only implement the technology under the supervision of field staff)

Main technical functions: control of concentrated runoff: retain / trap

Secondary technical functions: control of concentrated runoff: impede / retard, reduction of slope angle, reduction of slope length, increase of infiltration

Aligned: -contour
Vegetative material: G : grass
Number of plants per (ha): 2000
Vertical interval between rows / strips / blocks (m): 1
Spacing between rows / strips / blocks (m): 4
Vertical interval within rows / strips / blocks (m): 0.2
Width within rows / strips / blocks (m): 0.2

Grass species: Pennisetum

Slope (which determines the spacing indicated above): 35%

If the original slope has changed as a result of the Technology, the slope today is (see figure below): 0%

Gradient along the rows / strips: 0%

Terrace: bench level
Vertical interval between structures (m): 2
Spacing between structures (m): 4

Slope (which determines the spacing indicated above): 20-50%

If the original slope has changed as a result of the Technology, the slope today is: 0%

Lateral gradient along the structure: 0%

Vegetation is used for stabilisation of structures.

4.3 Informations générales sur le calcul des intrants et des coûts

autre/ monnaie nationale (précisez):

Rwandan francs

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

640,0

4.4 Activités de mise en place/ d'établissement

	Activité	Type de mesures	Calendrier
1.	Cuttings of grasses	Végétale	Rain season
2.	Transport of grass cuttings	Végétale	Rain season
3.	Planting of grass cuttings	Végétale	Rain season
4.	Land surveying (slope determination, soil structure and texture analysis)	Structurel	any time
5.	Construction of bunds (risers) with soil from upper and lower sides	Structurel	dry season
6.	Level terraces bed (surface soil moved from upper to lower part of terraces)	Structurel	dry season
7.	cutting subsurface soil, leveling and refilling surface soil	Structurel	dry season
8.	Make lips on edges of terraces	Structurel	dry season
9.	Compact risers	Structurel	dry season
10.	Plant grasses including agro-forestery trees.	Structurel	rainy season
11.	Input/ application of farmyard manure and liming	Structurel	rainy season

4.5 Coûts et intrants nécessaires à la mise en place

	Spécifiez les intrants	Unité	Quantité	Coûts par unité	Coût total par intrant	% des coût supporté par les exploitants des terres
Main d'œuvre	Cuttings of grasses	persons/day/ha	2,0	1000,0	2000,0	60,0
Main d'œuvre	Transport of grass cuttings	persons/day/ha	10,0	1000,0	10000,0
Main d'œuvre	Planting of grass cuttings	persons/day/ha	20,0	1000,0	20000,0	100,0
Main d'œuvre	Land surveying (slope determination, soil structure and texture	persons/day/ha	6,0	20000,0	120000,0
Engrais et biocides	Lime	kg/ha	2500,0	40,0	100000,0
Engrais et biocides	Famyard manure	kg/ha	30000,0	5,0	150000,0
Engrais et biocides	Mineral fertilizers	kg/ha	300,0	500,0	150000,0
Autre	Labour: Construction of bunds	persons/day/ha	100,0	1000,0	100000,0
Autre	Labour: Level terraces bed	persons/day/ha	250,0	1000,0	250000,0
Autre	Labour: Cutting subsurface soil	persons/day/ha	250,0	1000,0	250000,0
Autre	Labour: Make lips on edges of terraces	persons/day/ha	10,0	1000,0	10000,0
Autre	Labour: Compact risers	persons/day/ha	50,0	1000,0	50000,0
Autre	Labour: Plant grasses including agro-forestery trees	persons/day/ha	50,0	1000,0	50000,0
Coût total de mise en place de la Technologie					1262000,0

Commentaires:

Duration of establishment phase: 1 month(s)

4.6 Activités d'entretien/ récurrentes

	Activité	Type de mesures	Calendrier/ fréquence
1.	Weeding	Végétale	Before crop planting/each cropping season
2.	Manure application	Végétale	Before crop planting/annually
3.	Grass streaming	Végétale	Throughout the year
4.	Cleaning of channels and drains	Structurel	through out the year
5.	Regular repair of destroyed risers	Structurel	through the year

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	% des coût supporté par les exploitants des terres
Main d'œuvre	Weeding	persons/day/ha	5,0	1000,0	5000,0	100,0
Main d'œuvre	Manure application	persons/day/ha	10,0	1000,0	10000,0	100,0
Main d'œuvre	Grass streaming	persons/day/ha	2,0	1000,0	2000,0	100,0
Main d'œuvre	Cleaning of channels and drains	persons/day/ha	10,0	300,0	3000,0	100,0
Autre	Labour: Regular repair of destroyed risers	persons/day/ha	6,0	333,3333	2000,0	100,0
Coût total d'entretien de la Technologie					22000,0

Commentaires:

Machinery/ tools: Small hoes and machete, Hoes, machete, spade, A.fram, macako and meters.

The cost is calculated using the rate of US dollars at present time and were estimated according to the cost of construction of one radical terrace. At present the labor is 1.6$ per day. This was calculated on 25/07/2011.

4.8 Facteurs les plus importants affectant les coûts

Décrivez les facteurs les plus importants affectant les coûts :

Factors that affect the cost are labor, soil structure and slope

5.1 Climat

5.2 Topographie

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 fertility is low

Soil drainage / infiltration is good

Soil water storage capacity is low - medium

5.4 Disponibilité et qualité de l'eau

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

Water quality (untreated): Good drinking water available but very far to fetch.

5.5 Biodiversité

5.6 Caractéristiques des exploitants des terres appliquant la Technologie

Indiquez toute autre caractéristique pertinente des exploitants des terres:

Population density: 50-100 persons/km2

Annual population growth: 2% - 3%

75% of the land users are poor and own 60% of the land.
25% of the land users are poor and own 40% of the land.

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:

• individu, sans titre de propriété
• individu, avec titre de propriété

Droits d’utilisation des terres:

• individuel

Droits d’utilisation de l’eau:

• accès libre (non organisé)
• communautaire (organisé)

5.9 Accès aux services et aux infrastructures

6.1 Impacts sur site que la Technologie a montrés

Impacts socio-économiques

Production

Revenus et coûts

Impacts socioculturels

Impacts écologiques

Cycle de l'eau/ ruissellement

Sols

Réduction des risques de catastrophe et des risques climatiques

Autres impacts écologiques

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	bien

Extrêmes climatiques (catastrophes)

Catastrophes météorologiques

	Comment la Technologie fait-elle face à cela?
pluie torrentielle locale	pas bien

Catastrophes climatiques

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

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):

150 households covering 75 percent of stated area

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?

• 0-10%

Commentaires:

140 land user families have adopted the Technology with 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: The real advantages of the technology are observed after 5 to 6 years with good maintenance of structures

6.7 Points forts/ avantages/ possibilités de la Technologie

Points forts/ avantages/ possibilités du point de vue de l'exploitant des terres
It reduces soil runoff How can they be sustained / enhanced? Good maintenance of structures

Points forts/ avantages/ possibilités du point de vue du compilateur ou d'une autre personne ressource clé
It controls soil erosion How can they be sustained / enhanced? There is a need to plant grasses or trees on risers to stabilize terraces
It increases soil water holding capacity How can they be sustained / enhanced? Organic manure should be added to the terrace to effectively increase the soil water holding capacity.
It increases fodder availability as new niches for fodder production are created. How can they be sustained / enhanced? High value nutritive fodder should be planted (napier grass, calliadra, tripsucum, etc.) on risers
It increases crop productivity How can they be sustained / enhanced? Terraces should be well maintained by providing more inputs and regular maintenance of bench struactures

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

Faiblesses/ inconvénients/ risques du point de vue de l’exploitant des terres	Comment peuvent-ils être surmontés?
It reduces the cropped land	Farmers should be supported in accessing high value crops and inputs to maximize crop yield.

Faiblesses/ inconvénients/ risques du point de vue du compilateur ou d'une autre personne ressource clé	Comment peuvent-ils être surmontés?
The establishment of radical terraces is expensive	The construction of radical terraces should be subsided by the government.
The initial soil structure is disturbed (lost of soil organic matter)	Heavy investments are needed to replenish the soil fertility, especially by adding organic manure.
The establishment of radical terraces decreases cropped land.	Grow high value crops and use adequate quantity of inputs.
With poor maintenance or poor design of radical terraces, landslides may occur.	To be much more rigorous in the design and implementation/development of terraces by making sure that professionals are involved in the whole process of establishing terraces.

7.2 Références des publications disponibles

Titre, auteur, année, ISBN:

Kagera TAMp project website

Disponible à partir d'où? Coût?

http://www.fao.org/nr/kagera/en/