1.2 Detalhes do contato das pessoas capacitadas e instituições envolvidas na avaliação e documentação da tecnologia

Nome da(s) instituição(ões) que facilitou(ram) a documentação/ avaliação da Tecnologia (se relevante)

Mekelle University (Mekelle University) - Etiópia

1.3 Condições em relação ao uso da informação documentada através de WOCAT

Quando os dados foram compilados (no campo)?

10/11/2012

O compilador e a(s) pessoa(s) capacitada(s) aceitam as condições relativas ao uso de dados documentados através do WOCAT:

Sim

2.1 Descrição curta da tecnologia

Definição da tecnologia:

Compacted soil bund constructed following a contour using a soil excavated from deep trenches on the up-slope side.

2.2 Descrição detalhada da tecnologia

Descrição:

Soil faced deep trench bund is constructed by excavating trenches of 1 m deep, 0.5 - 1 m wide and 2 - 3.5 m long with spacing between trenches of 0.3 - 0.5 m along the contour and using the excavated soil to construct a compacted bund downslope. The smaller dimensions are usually used in cultivated lands while the larger are implemented in grazing lands.

Purpose of the Technology: Soil faced deep trench bund decreases slope length, runoff velocity and soil loss; and increases runoff harvesting, soil moisture and groundwater recharge.

Establishment / maintenance activities and inputs: Construction of soil faced deep trench bund involves alignment of a contour, excavation of trenches, construction and compaction of bund and planting grass, while the maintenance involves dredging of sediment from the trenches and use it for reinforcing the embankment.

Line level, tape meter, digging hoe, shovel and grass are needed for the establishment and maintenance.

Natural / human environment: The technology is implemented in moderate (5 - 8%) and hill (8 - 16%) slopes and in medium and heavy soil types of at least 1 m depth. It reduces runoff amount and velocity thereby decreasing soil loss and desertification/land degradation. It also improves soil moisture availability and groundwater recharge by encouraging lateral and vertical movement of water respectively.

It is mostly constructed using communal labour and there is an encouraging trend of spontaneous adoption. The technology is witnessed to be increasing crop and fodder production thereby improving the livelihood of the land users. It, however, is labour intensive and slightly reduces farm size.

2.3 Fotos da tecnologia

2.5 País/região/locais onde a tecnologia foi aplicada e que estão cobertos nesta avaliação

2.7 Introdução da tecnologia

Especifique como a tecnologia foi introduzida:

• através de projetos/intervenções externas

3.1 Principal/principais finalidade(s) da tecnologia

• Reduz, previne, recupera a degradação do solo

3.2 Tipo(s) atualizado(s) de uso da terra onde a tecnologia foi aplicada

Comentários:

Major land use problems (compiler’s opinion): Soil erosion, overgrazing, decline of soil fertility and productivity.

Major land use problems (land users’ perception): Soil erosion, reduced soil depth, fertility and productivity.

3.3 Mais informações sobre o uso da terra

Abastecimento de água para a terra na qual a tecnologia é aplicada:

• Precipitação natural

Número de estações de cultivo por ano:

• 1

Especifique:

Longest growing period in days: 150 Longest growing period from month to month: June - November

Densidade animal (se relevante):

50-100 LU /km2

3.4 Grupo de GST ao qual pertence a tecnologia

• Medidas de curva de nível
• Gestão do lençol freático

3.5 Difusão da tecnologia

Especifique a difusão da tecnologia:

• Uniformemente difundida numa área

Caso a tecnologia seja uniformemente difundida numa área, indique a área coberta aproximada:

• 10-100 km2

3.6 Medidas de GST contendo a tecnologia

Comentários:

Main measures: structural measures

Secondary measures: vegetative measures

Type of vegetative measures: aligned: -contour

3.7 Principais tipos de degradação da terra abordados pela tecnologia

Comentários:

Main type of degradation addressed: Wt: loss of topsoil / surface erosion

Secondary types of degradation addressed: Wg: gully erosion / gullying, Bc: reduction of vegetation cover

Main causes of degradation: soil management, overgrazing, Heavy / extreme rainfall (intensity/amounts), population pressure

Secondary causes of degradation: crop management (annual, perennial, tree/shrub) (Crop residues are removed during harvesting), over-exploitation of vegetation for domestic use, change of seasonal rainfall, droughts, land tenure, poverty / wealth, education, access to knowledge and support services

3.8 Redução, prevenção ou recuperação da degradação do solo

Especifique o objetivo da tecnologia em relação a degradação da terra:

• Reduzir a degradação do solo
• Recuperar/reabilitar solo severamente degradado

Comentários:

Main goals: mitigation / reduction of land degradation
Secondary goals: rehabilitation / reclamation of denuded land

4.1 Desenho técnico da tecnologia

4.2 Especificações técnicas/ explicações do desenho técnico

Soil faced deep trench bunds are structures constructed by excavating trenches following the contour and using the excavated soil to establish compacted bund on the lower side.

Location: Tigray. Kilte Awlaelo

Date: 10/10/2014

Technical knowledge required for field staff / advisors: moderate

Technical knowledge required for land users: low

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

Secondary technical functions: increase of infiltration, increase / maintain water stored in soil, increase of groundwater level / recharge of groundwater, sediment retention / trapping, sediment harvesting

Aligned: -contour
Vegetative material: G : grass
Number of plants per (ha): 1600
Vertical interval between rows / strips / blocks (m): 1 - 1.2
Spacing between rows / strips / blocks (m): 10 - 15
Vertical interval within rows / strips / blocks (m): 0.5

Grass species: Elephant grass is mostly planted on the bunds in a single row at spacing of 0.5 m.

Slope (which determines the spacing indicated above): 6.5 and 12%

Gradient along the rows / strips: 0%

Bund/ bank: level
Vertical interval between structures (m): 1 - 1.2
Spacing between structures (m): 10 - 15
Depth of ditches/pits/dams (m): 1
Width of ditches/pits/dams (m): 0.5 - 1
Length of ditches/pits/dams (m): 2 - 3.5
Height of bunds/banks/others (m): 0.75 - 1
Width of bunds/banks/others (m): 0.3 - 1.2
Length of bunds/banks/others (m): 60 - 100

Construction material (earth): Soil excavated from the trenches is used to construct bunds

Slope (which determines the spacing indicated above): 6.5 and 12%

Lateral gradient along the structure: 0%

Vegetation is used for stabilisation of structures.

4.3 Informação geral em relação ao cálculo de entradas e custos

Outro/moeda nacional (especifique):

Birr

Indique a taxa cambial do dólar norte americano para a moeda local (se relevante): 1 USD =:

18,0

4.4 Atividades de implantação

	Atividade	Tipo de medida	Periodicidade
1.	Purchase of elephant grass	Vegetativo	June/July
2.	Grass plantation	Vegetativo	July
3.	Contour alignment, marking trench dimensions, trench excavation and construction and compaction of bund	Estrutural	January - May

4.5 Custos e entradas necessárias para a implantação

	Especifique a entrada	Unidade	Quantidade	Custos por unidade	Custos totais por entrada	% dos custos arcados pelos usuários da terra
Mão-de-obra	Labour	ha	1,0	2119,0	2119,0	60,0
Equipamento	Tools	ha	1,0	44,0	44,0
Material vegetal	Seedlings	ha	1,0	36,0	36,0
Custos totais para a implantação da tecnologia					2199,0

Comentários:

Duration of establishment phase: 48 month(s)

4.6 Atividades recorrentes/manutenção

	Atividade	Tipo de medida	Periodicidade/frequência
1.	Dredging of deposited sediment from trenches and compacting it on the bund	Estrutural	January - May

4.7 Custos e entradas necessárias pata a manutenção/atividades recorrentes (por ano)

	Especifique a entrada	Unidade	Quantidade	Custos por unidade	Custos totais por entrada	% dos custos arcados pelos usuários da terra
Mão-de-obra	Labour	ha	1,0	833,0	833,0	100,0
Custos totais para a manutenção da tecnologia					833,0

Comentários:

Machinery/ tools: Digging hoe, shovel (Costs are included in the structural measures), Line level, tape meter, digging hoe, shovel

The cost was calculated for an average bund length and spacing of 80 m and 12.5 m respectively, which would result in a construction of 10 bunds per ha. In addition, an average trench length and spacing between trenches along the contour of 2.75 m and 0.4 m was considered respectively resulting in 25 trenches per bund and 250 trenches per ha.

The excavation of one deep trench and construction of the corresponding bund requires 3 person days during establishment while maintaining it needs 1.5 person days per year. A single row of grass is planted on the bunds at 0.5 m interval and a person is assumed to plant about 100 seedlings per day. The cost calculation rates apply to 2012. Accordingly, the price of single elephant grass is 0.4 Birr and the daily labour wage is 40 Birr for light work such as grass planting and 50 Birr for medium work such as trench excavation.

4.8 Fatores mais importantes que afetam os custos

Descreva os fatores mais determinantes que afetam os custos:

Labour, slope, landuse, soil depth.

5.1 Clima

5.2 Topografia

Comentários e outras especificações sobre a topografia:

Slopes on average: An average slope of 6.5% is taken for moderate slope and 12% for hill slope.

5.3 Solos

Caso disponível anexe a descrição completa do solo ou especifique as informações disponíveis, p. ex. tipo de solo, PH/acidez do solo, nitrogênio, capacidade de troca catiônica, salinidade, etc.

Soil depth on average: The deep trench should usually be 1 m deep.
Soil texture: Medium (ranked 1) and fine/heavy (ranked 2, Appropriate in case of grazing lands.)
Soil fertility: Low (ranked 1) and medium (Clay soils in rehabilitated grazing lands, ranked 2.)
Topsoil organic matter: Low (more in cultivate lands, ranked 1) and Medium (more in grazing lands, ranked 2)
Soil drainage/infiltration is medium (ranked 1) and poor (in clay soils, ranked 2)
Soil water storage capacity is medium (ranked 1) and high (ranked 2)

5.4 Disponibilidade e qualidade de água

5.5 Biodiversidade

5.6 Características dos usuários da terra que utilizam a tecnologia

Indique outras características relevantes dos usuários da terra:

Land users applying the Technology are mainly common / average land users
Population density: 100-200 persons/km2
Annual population growth: 2% - 3%
10% of the land users are rich and own 10% of the land.
60% of the land users are average wealthy and own 55% of the land (35 birr/person/day).
30% of the land users are poor and own 35% of the land.

5.7 Média da área de terra própria ou arrendada por usuários da terra que utilizam a tecnologia

5.8 Propriedade de terra, direitos de uso da terra e de uso da água

Propriedade da terra:

• Estado

Direitos do uso da terra:

• Comunitário (organizado)
• Indivíduo

5.9 Acesso a serviços e infraestrutura

6.1 Impactos no local mostrados pela tecnologia

Impactos socioeconômicos

Produção

Renda e custos

Impactos socioculturais

Impactos ecológicos

Ciclo hídrico/escoamento

Solo

6.2 Impactos externos mostrados pela tecnologia

6.4 Análise do custo-benefício

Como os benefícios se comparam aos custos de implantação (do ponto de vista dos usuários da terra)?

Como os benefícios se comparam aos custos recorrentes/de manutenção(do ponto de vista dos usuários da terra)?

6.5 Adoção da tecnologia

Se disponível, determine a quantidade (número de unidades familiares e/ou área abordada):

8735

Entre todos aqueles que adotaram a tecnologia, quantos adotaram espontaneamente, ou seja, sem receber nenhum incentivo material/pagamentos?

• 50-90%

Comentários:

27% of land user families have adopted the Technology with external material support

2541 land user families have adopted the Technology with external material support

73% of land user families have adopted the Technology without any external material support

6194 land user families have adopted the Technology without any external material support

There is a moderate trend towards spontaneous adoption of the Technology

6.7 Pontos fortes/vantagens/oportunidades da tecnologia

Pontos fortes/vantagens/oportunidades na visão do usuário da terra
Reduce soil erosion and increase soil fertility How can they be sustained / enhanced? Continuous maintenance and excavation of sediment
Increase soil moisture and yield How can they be sustained / enhanced? Planting grass, sunflower and other fodder plants on the bund to increase conservation as well as economic benefits
Reduce surface runoff, increase water storage in trenches and recharging downstream springs How can they be sustained / enhanced? Continuous maintenance and excavation of sediment

Pontos fortes/vantagens/oportunidades na visão do compilador ou de outra pessoa capacitada
Decreased slope length, reduced runoff amount and velocity and soil erosion How can they be sustained / enhanced? Continuous maintenance of the structures and controlled grazing of the grass
Increase in rainwater harvesting, soil moisture and groundwater recharge How can they be sustained / enhanced? Continuous maintenance of the structures
Increase in crop and fodder production How can they be sustained / enhanced? Planting improved and high yielding crop and fodder varieties

6.8 Pontos fracos, desvantagens/riscos da tecnologia e formas de superá-los

Pontos fracos/desvantagens/riscos na visão do usuário da terra	Como eles podem ser superados?
Reduced farm land	Increase the productivity of the bunds.
Increased labour requirement	Mass mobilization and/or increased incentives to households.

Pontos fracos/vantagens/riscos na visão do compilador ou de outra pessoa capacitada	Como eles podem ser superados?
Labour intensive	Mass mobilization and improving the design.
Reduced farm land	Increasing the spacing and reduce dimension of bunds without compromising their effectiveness.

7.2 Referências às publicações disponíveis

Título, autor, ano, ISBN:

Staff members of the Kilte Awlaelo Wereda Office of Agriculture and Rural Development

Título, autor, ano, ISBN:

Carucci, V. (2000). Guidelines on Water Harvesting and Soil Conservation for Moisture Deficit Areas in Ethiopia:the productive use of water and soil. First draft manual for trainers, Addis Ababa, Ethiopia.

Título, autor, ano, ISBN:

Lakew, D., Carucci, V., Asrat, W. and Yitayew, A. (2005). Community Based Participatory Watershed Development: A guideline. Part I, first edition, Ministry of Agriculture and Rural Development, Addis Ababa, Ethiopia.