1.2 Contact details of resource persons and institutions involved in the assessment and documentation of the Technology

Name of project which facilitated the documentation/ evaluation of the Technology (if relevant)

1.3 Conditions regarding the use of data documented through WOCAT

The compiler and key resource person(s) accept the conditions regarding the use of data documented through WOCAT:

Yes

1.4 Declaration on sustainability of the described Technology

Is the Technology described here problematic with regard to land degradation, so that it cannot be declared a sustainable land management technology?

No

1.5 Reference to Questionnaire(s) on SLM Approaches (documented using WOCAT)

Community Organizations and Mobilization for Soil and Water … [Ethiopia]

Community mobilization for soil and water conservation work in a watershed planning unit is an approach for collective action by organizing all active labor forces living in the kebele/peasant association into development group of 20-30 members and further divide into 1:5 work force to implement construction of soil and water …

• Compiler: Gizaw Desta Gessesse
• 03/14/2014 midnight

'Cut and Carry' Grazing system or 'Zero Grazing' … [Ethiopia]

Cut and carry grazing system (alternatively called zero grazing) is an approach where the community is consulted to identify and agree on areas to be closed and protected from free grazing; establish user groups are established to share the fodder biomass harvested from communal closed areas equitably; they utilize tree/shrub …

• Compiler: Gizaw Desta Gessesse
• 05/16/2014 midnight

2.1 Short description of the Technology

Definition of the Technology:

Vegetated graded soil bund is a soil conservation practice meant for cultivated lands and constructed by excavating graded channel on upper side and develop embankment on lower side which is planted with grass or shrub species in order to control soil erosion and drain excess runoff implemented through community mobilization.

2.2 Detailed description of the Technology

Description:

Vegetated graded soil bund is a practice or soil conservation technology for cultivated lands and constructed by excavating graded channel and form embankment. It is practiced in areas where there is excess runoff to be disposed and where there is no stones available for construction. The design specifications (ditch gradient, width and height) and layout (spacing/vertical interval) vary on the amount of excess runoff and slope of the land. Soil bund construction begins from top of the catchment. Cut off drains are constructed on top of the catchment and where needed to drain excess runoff to well stabilized natural or man-made waterways. this helps to reduce runoff impact on gullies. The bund ditch/channel should be sufficient enough to drain excess runoff safely without causing channel erosion and creating downstream damages. At same time the embankment should be stable to withstand overflows and damage due to free grazing. One technique to stabilize bunds is to plant the embankment with grass and shrub species of multiple economic value in order to compensate production area lost by bund construction. Often, the species are preferably used for livestock feed. Thus, free grazing has to be controlled. To protect damage of channels and embankments by extreme runoff and floods, frequent supervision and maintenance is required.

The purposes are:
1) Reduce nutrient loss and soil erosion by shortening the slope length,
2) Safely drain excess runoff from upstream of gully into protected waterways,
4) Produce biomass of fodder and cash values.

Vegetated graded bunds are established by doing surveying using hand level to determine the layout of the technology along the slope. During the surveying, the position of bunds (spacing) and cutoff drains and connection to waterways are determined. Bunds are laid following 0.05% gradient and up to 80 m maximum length. The specifications of the structure are: height of bund is a minimum of 60 cm after compaction; depending on the soil, base width range between 1.0 and 1.5m; top width is between 30 and 50 cm. The construction is made across different parcels owned by different land users. If there is no natural waterways and where it is appropriate, paved waterways are constructed at every 80 m or less bund length to dispose drainage water. At the beginning of the rainy season, the embankments are covered with grass and/or shrubs either by direct sowing of seeds or planting the seedlings raised in the nurseries. Monitoring of damages due to flooding and animals, maintenance of the structure as well as replanting of dead seedlings on bunds is required to sustain the soil conservation technology.

The technology is appropriately applied in high rainfall and sub-humid areas of the sub-tropics, particularly where the soil is moderately deep and poorly drained. It is constructed on cultivated lands having slopes in the range of 3-15%. The practice can be constructed by land users. It also requires collective decision and actions to drain excess runoff through waterways. The living condition depends on subsistence crop-livestock mixed farming. On average households have 5-6 family size. Crop production is meant for home consumption with small surplus for local market. The services related to water supply, energy supply, and infrastructure are low. Besides it is an asset, animals often used to cope shocks during drought periods.

2.3 Photos of the Technology

2.5 Country/ region/ locations where the Technology has been applied and which are covered by this assessment

2.6 Date of implementation

If precise year is not known, indicate approximate date:

• less than 10 years ago (recently)

2.7 Introduction of the Technology

Specify how the Technology was introduced:

• through projects/ external interventions

Comments (type of project, etc.):

The soil bunds are introduced before 30-40 years, however the integration of structural and combination of vegetative measures are applied in three years period in the WLRC learning watersheds.

3.1 Main purpose(s) of the Technology

• reduce, prevent, restore land degradation

3.2 Current land use type(s) where the Technology is applied

Cropland

• Annual cropping
• Perennial (non-woody) cropping
• Tree and shrub cropping

• Rhamnus, Napier grass

• Cordia Africana, Polycantha, Sesbania Susban, Pigeon pea, Treelucer

Number of growing seasons per year:

• 1

Specify:

Longest growing period in days: 210, Longest growing period from month to month: June-December; Second longest growing period in days: 180, Second longest growing period from month to month: June-November

Grazing land

• free grazing

Comments:

Major land use problems (compiler’s opinion): Land degradation due to sheet erosion, rills and gullies, soil nutrient depletion, overgrazing, shortage of fuel wood, excessive removal of crop residuals, loss of vegetation and deforestation
Major land use problems (land users’ perception): Soil erosion, soil nutrient depletion, shortage of pasture

3.4 Water supply

Water supply for the land on which the Technology is applied:

• full irrigation

3.5 SLM group to which the Technology belongs

• cross-slope measure

3.6 SLM measures comprising the Technology

vegetative measures

• V1: Tree and shrub cover
• V2: Grasses and perennial herbaceous plants

structural measures

• S2: Bunds, banks
• S3: Graded ditches, channels, waterways

Comments:

Type of vegetative measures: aligned: -graded strips

3.7 Main types of land degradation addressed by the Technology

soil erosion by water

• Wt: loss of topsoil/ surface erosion
• Wo: offsite degradation effects

water degradation

• Hs: change in quantity of surface water

Comments:

Main causes of degradation: soil management (High tillage frequency on annual basis and steep slope cultivation), crop management (annual, perennial, tree/shrub) (The cropping system is cereal based that induce erosion), overgrazing (Livestock graze on crop residues after harvesting of crops), Heavy / extreme rainfall (intensity/amounts) (Extreme rainfall cause for high erosion), other natural causes (avalanches, volcanic eruptions, mud flows, highly susceptible natural resources, extreme topography, etc.) specify (Steep slopes or rugged topography), population pressure (Result in expansion of crop lands to steeper slopes)
Secondary causes of degradation: deforestation / removal of natural vegetation (incl. forest fires) (Deforestation of scattered trees in the farm and forests upstream of crop lands), land tenure (Insecure tenure play role not to invest on long term), poverty / wealth (Poor can not afford to invest on soil conservation on his parcel), education, access to knowledge and support services, governance / institutional

3.8 Prevention, reduction, or restoration of land degradation

Specify the goal of the Technology with regard to land degradation:

• reduce land degradation

4.1 Technical drawing of the Technology

Technical specifications (related to technical drawing):

Vegetated graded soil bund showing the excavated ditch or channel and the embankment planted with grass and shrubs
Location: Amhara Region. Mecha, Yilmana Densa, Bahir Dar Zuria and Dessie Z

Technical knowledge required for field staff / advisors: high (Layout and design specification of soil bunds and cutoff drains vary on soil types, slopes, and rainfall conditions. Experts thus should acquire knowledge on specific hydrologic conditions)
Technical knowledge required for land users: moderate (Land users need skill to layout and construct bunds, monitor structures before the occurrence of excessive damage, and do regular maintenance)

Main technical functions: control of dispersed runoff: impede / retard, reduction of slope length, sediment retention / trapping, sediment harvesting, increase of biomass (quantity)
Secondary technical functions: control of dispersed runoff: retain / trap, reduction of slope angle, increase / maintain water stored in soil, increase of groundwater level / recharge of groundwater

Aligned: -graded strips
Vegetative material: T : trees / shrubs, C : perennial crops, G : grass
Number of plants per (ha): T=5333, C=160, G=1600
Vertical interval between rows / strips / blocks (m): 1-1.5
Spacing between rows / strips / blocks (m): 10-20
Vertical interval within rows / strips / blocks (m): T=0.3, C=5, G=0.5
Width within rows / strips / blocks (m): 0.3
Trees/ shrubs species: Cordia Africana, Polycantha, Sesbania Susban, Pigeon pea, Treelucer
Perennial crops species: Rhamnus
Grass species: Napier grass
Slope (which determines the spacing indicated above): 3-15%
Gradient along the rows / strips: 0.05%
Diversion ditch/ drainage
Depth of ditches/pits/dams (m): 0.3-0.7
Width of ditches/pits/dams (m): 1.2-2.8
Length of ditches/pits/dams (m): 100-250

Waterway
Depth of ditches/pits/dams (m): 0.3
Width of ditches/pits/dams (m): 1.5-2.0

Bund/ bank: graded
Vertical interval between structures (m): 1-1.5
Spacing between structures (m): 10-20
Depth of ditches/pits/dams (m): 0.5
Width of ditches/pits/dams (m): 0.3
Height of bunds/banks/others (m): 0.6
Width of bunds/banks/others (m): 1-1.5
Length of bunds/banks/others (m): 50-80

Construction material (earth): in-situ excavated soil
Slope (which determines the spacing indicated above): 3-15%
Lateral gradient along the structure: 0.05%
Vegetation is used for stabilisation of structures.

Author:

Bekure Melesse, WLRC, P.O.Box 8707, Addis Ababa, Ethiopia

4.2 General information regarding the calculation of inputs and costs

other/ national currency (specify):

ETH BIRR

If relevant, indicate exchange rate from USD to local currency (e.g. 1 USD = 79.9 Brazilian Real): 1 USD =:

20.0

4.3 Establishment activities

4.4 Costs and inputs needed for establishment

Comments:

Duration of establishment phase: 15 month(s)

4.5 Maintenance/ recurrent activities

4.6 Costs and inputs needed for maintenance/ recurrent activities (per year)

Comments:

Machinery/ tools: Cart, plastic tubes, spade, pickaxe, hand level, graduated ranging pole, spade, pickaxe, crowbar, hammer
The costs are calculated based on the labour, seedling/seed, grass splits required per hectare

4.7 Most important factors affecting the costs

Describe the most determinate factors affecting the costs:

The cost variation in implementing vegetated soil bund is dependent upon availability of stones, workability of the soil, cost of seeds or seedlings for plantation, and distance for transporting seedlings.

5.1 Climate

5.2 Topography

5.3 Soils

5.4 Water availability and quality

5.5 Biodiversity

5.6 Characteristics of land users applying the Technology

Indicate other relevant characteristics of the land users:

Land users applying the Technology are mainly common / average land users
Difference in the involvement of women and men: Women are involved in the construction of bunds with role of collecting stones, stabilize/compact the embankments and sometimes help men in excavating the earth
Population density: 200-500 persons/km2
Annual population growth: 2% - 3%
80% of the land users are average wealthy.
20% of the land users are poor.
Off-farm income specification: Land users often do not have access to off-farm income unless those who are young and own small size of land go for seasonal labor to towns during the slack period

5.7 Average area of land used by land users applying the Technology

5.8 Land ownership, land use rights, and water use rights

Land ownership:

• state

Land use rights:

• individual

Water use rights:

• open access (unorganized)
• communal (organized)

5.9 Access to services and infrastructure

6.1 On-site impacts the Technology has shown

Socio-economic impacts

Production

Income and costs

Socio-cultural impacts

Ecological impacts

Water cycle/ runoff

Soil

6.2 Off-site impacts the Technology has shown

6.3 Exposure and sensitivity of the Technology to gradual climate change and climate-related extremes/ disasters (as perceived by land users)

Climate-related extremes (disasters)

Meteorological disasters

Hydrological disasters

Comments:

The technology has sufficient drainage ditch to tolerate excess runoff occurred during heavy rainfall events. However, it is sensitive to floods unless flood management measures such as strong cutoff drains and waterways are implemented

6.4 Cost-benefit analysis

How do the benefits compare with the establishment costs (from land users’ perspective)?

How do the benefits compare with the maintenance/ recurrent costs (from land users' perspective)?

Comments:

The short term economic benefits of the technology includes increase in fodder production and slightly crop productivity due to improved soil moisture. Whereas the long term benefit can be obtained as a result of increased yield on areas where sediment accumulation occurs as well as production of fodder on soil bunds for livestock feed

6.5 Adoption of the Technology

Comments:

The technology is implemented using community mobilization approach which involves all land users. All land users, who cultivate land in areas where bunds are suitable, implemented the technology. All parcels are covered with the technology/bunds except homesteads and degraded hillsides and gullies which are treated with different SLM technologies
Since the approach encourages collective action (through community organizations) to integrate different SLM technologies in the watershed level, there is no attempt by individual land users. However, there are motivations and implementation of land users on adjacent watersheds to implement the technology.
There is a moderate trend towards spontaneous adoption of the Technology
The trend is at increasing rate although land users need material support such as multipurpose seedlings to stabilize bunds. There is shortage of supply of fodder seeds. Community nurseries are inadequate and not well supported to raise seedlings to meet community demands.

6.7 Strengths/ advantages/ opportunities of the Technology

6.8 Weaknesses/ disadvantages/ risks of the Technology and ways of overcoming them

7.1 Methods/ sources of information

7.2 References to available publications

Title, author, year, ISBN:

Vegetated Graded Soil Bund: A Technique to Reduce Runoff Impact and Increase Soil Moisture Storage and Fodder Biomass, WLRC Brief No. 4

Available from where? Costs?

WWW.wlrc-eth.org