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To effectively Water Spreading Bunds the following should be carried out:

• Step 1: Farmers should consider making earth bunds by hand, animal ploughs or mechanised ploughs.
• Step 2: Contour bunds:
  • Contour lines must be plotted and marked prior to developing the bund.
  • A 40 cm deep infiltration pit is dug directly above where the bund will be plotted.
  • Bunds should be spread 5 m to 10 m apart.
  • Material from the infiltration pit will be piled and compacted to form a 25 cm to 30 cm in height with a base of 75 cm.
  • Soil is piled to form a ridge along the contour. The more significant the slope, the closer the bunds must be plotted.
• Step 3: Semi-circle bunds:
  • Contour lines must be plotted and marked prior to developing the bund.
  • A centre point is chosen as diameter for the bund is selected (this could be 3 m or 30 m depending on the available space). From the centre point a string is used to stake out an even semi-circle.
  • Excavate a small trench before the bund and pile the excavated material. Pile and compact a bund wall, wetting it often to form the wall.
• Step 4: Contour stone bunds:
  • Developed on less steep slopes.
  • Must have access to local stones.
  • Dig out a shallow ditch, 10 cm to 15 cm in depth.
  • Lay largest stones at the bottom of the ditch and pile smaller stone upward.
  • Step 5: Regular monitoring of bunds should take place, especially after rain events or after significant periods of time. Repairs should be done if any damage is found.

To effectively implement Half-moon techniques, the following steps should be carried out:

• Step 1: Farmers should consider the diameter of the half-moon  between 2 m – 3 m, with a total surface area of approximately 1.5 sqm and 3.5 sqm.
• Step 2: Pits should be dug to a depth of between 15 cm to 30 cm.
• Step 3: Excavated material can be piled around the curved section of the half-moon.
• Step 4: The curved section of the half-moon can be reinforced by stones to prevent washouts of the half-moon.
• Step 5: 35 kg of organic fertilisers/compost should be evenly distributed in the half-moon.

To effectively In Field Water Harvesting techniques, the following steps should be carried out:

• Step 1: Land is cleared, berms are developed, and crops are planted in order to direct water to the infiltration point.
• Step 2: The catchment areas should be sloped no more than 5 % and the area should be cleared to promote catchment as much as possible.
• Step 3: The infiltration pit (where water is stored) should be dug at the lowest point of the catchment areas and line infiltration pits with plastic or concrete roofing to limit water loss, and can be used as a source of irrigation for fruit trees and other high value crops.
• Step 4: Paths can be built of soil to guide water to the infiltration pit.
• Step 5: Alley cropping, or strop cropping can be used, with areas between trees and crops dug deeper like a trough to direct water to the infiltration pit.
• Step 6: To access water from infiltration pits, farmers can introduce a pumping system and water can be distributed around the farm as necessary

To effectively implement drip irrigation:

• Step 1: A reliable water source must be available - natural (natural or through rain-water harvesting).
• Step 2: Acquire a pump system (approximately $US 100) that maintains enough pressure to deliver water through the system or an elevated tank.
• Step 3: Connect lines or hoses and laterals that run from the pump system across the planted fields.
• Step 4: Run lines or hoses with emitters (drippers) or small punctures at the surface level along planted crops or just below the surface providing water to the roots system of the plants.
• Step 5: Once the system is operable, the pump can be turned on and water dispersed as required by the nature of the crop and can also be implemented with supplemental irrigation strategies (Technical Brief 23).
• Step 6: Monitor the irrigation system regularly to ensure there are no malfunctions and the system is maintained. Crops that receive regular water can develop shallow root systems and any prolonged disruptions in service could have   significant impacts.
• Step 7: If applying drip irrigation in sloped conditions, follow the contours of the slope as outlined in Technical Brief 16.

Once a drip irrigation system is up and running, farmers can explore fertigation, the addition of soluble fertilisers into the irrigation system water for distribution directly to plants.

To effectively implement solar irrigation:

• Step 1: To determine the solar pump system Crop water requirements, location, water sources etc. Do required research. Is water sourced from an above ground or below ground source?
• Step 2: Source required materials to implement a solar irrigation system from regional or international suppliers including:
  • Photovoltaic (PV) panels to generate electricity (80-300 W system depending on context);
  • a structure to mount the panels;
  • a pump controller;
  • a surface or submersible water pump; and
  • a distribution system or storage tank for water.
• Step 3: Identify funding sources as initial costs, as well as maintenance costs, must be considered and modelled prior to purchasing a system. There are regional and international solar irrigation producers.   These costs differ dramatically given the complexity of the context, starting at costs approximately USD $2,400 for equipment only. If drilling is necessary the cost increases significantly depending on depth, substrate etc.  Community-based investment, micro-leasing and rental services can be possible funding models to explore.
• Step 4: Determine whether there is sufficient solar irradiation for the proposed area – consult and specialist; and/or the national meteorological service.
• Step 5: Identify area suitable to install solar panels. The area should be easily accessible, and all trees/bush should be cleared. To determine most appropriate site and angle of panels, etc, consult an expert.
• Step 6: The availability of technical expertise must be considered before implementation to ensure that any technical issues do not result in long period of service disruption.

Maintenance costs and expertise should be considered before installing solar irrigation systems. A detailed cost benefit analysis is advisable. Other key technical considerations include: Legal permits to extract water from the source as water extraction may impact community watershed levels.

To effectively approach to terracing construction:

• Step 1: Measure slope angle – should not exceed 25 degrees and soils should be at least 0.5 metres deep.
• Step 2: Plot the contours – see Technical Brief 16 Contour Planting for instructions for staking-out contours, and the diagram below for use of a t-stick to measure the distance between contours.
• Step 3: Start at the lowest terrace. Dig a trench vertically below the next contour, and then dig outwards to the lowest contour. Remove soil and place downhill below the lowest contour.
• Step 4: Compact soil on constructed terrace.
• Step 5: Work should then progress upslope, emptying top-soil on to the terrace below to provide soil for planting.
• Step 6: Strengthen riser buttress walls (back-walls) with stones, compacted soil, or by planting grass or trees.
• Step 7: Terrace-end drainage should also be considered, so water does not pool too heavily. The down-field gutters can be lined with stones to reduce erosion

Detailed diagrams and tables for calculating terrace dimensions are provided in Peace Corps 1986, Soil conservation techniques for hillside farming.

Additional guidance can be sought from videos provided by Access Agriculture: SLM02 Fanya Juu terraces. The Kenyan example provided is also up-slope terrace construction but using a different method where a trench is dug, and the loose topsoil is thrown up-hill (fanya juu in Kiswahili) which forms a ridge that flattens over time.

To effectively undertake contour planting:

• Step 1: Construct an A-frame that has a plumb-line with a rock hanging down the centre. The base of the A-frame should be 90 cm.
• Step 2: Calibrate the A-frame on flat ground. Ensure that both legs are on the ground. Mark where the plumb line meets the cross bar.
• Step 3: On a slope, working perpendicular to the slope, plant one leg of the A-frame and swing the other leg around until the plumb line meets the mark on the cross bar. Drive a stake into the ground where the first ‘planted’ leg is and continue the process across the slope.
• Step 4: Once the extent of the contour has been staked, tie a string from post-to-post across the slope; this identifies the contour to be planted.
• Step 5: Plant selected crops, develop contour ridges or plant contour strips along the contour line.
• Step 6: Subsequent contours should be spaced 3-5 m up or downhill of the preceding contour line. To determine the length between contour lines, measure off the top of each stake to a stake up or downhill with a tape measure or accurately measured third stick.
• Step 7: Contour ridges can be implemented like Water Spreading Bunds (Technical Brief 28) to form ridges of soil that are formed by tilling or ploughing and can be left after land preparation to further prevent erosive forces. Crops can be planted between these ridges.
• Step 8: The planting of contour strips can be implemented by planting grasses or hedges 20 m (shallow slopes) to 10 m (steeper slopes) apart up or downhill, similar to Trash Lines (Technical Brief 14). This intercropping allows for erosion control and can be used as fodder for livestock.

Without a topographic survey, this technology may require trial and error to begin with, to see how rainfall and run-off responds to the contouring. To effectively implement erosion control measures the following should be carried out:

• Step 1: Perform a thorough local study of the landscape, soils, land use and erosive processes that most impact the area: steep slopes, flood plains, high winds etc.
• Step 2: Source a large number of stones, preferably five to ten centimetres square blocks (from a quarry) or five to ten-centimetre diameter cobbles (from a river-bed). You will need 30 to 50 tonnes of stone per hectare for contour bunds approximately 300 metres long.
• Step 3: Mark out contours, as discussed in Technical Brief 16 Contour Planting.
• Step 4: In larger fields with shallower slopes, place stones in rows of two along contour line, interlocking alternately, burying the lower half. The bunds can be between 25 and 40 metres apart. On steeper slopes, stack and bury stones against or in vertical/near vertical walls of contours much closer together (five to ten metres apart) to reinforce them.
• Step 5: Make sure that stone bunds follow the contours from one side of the field to the other, ensuring that no ‘pour’ points (larger gaps) exist along the way, lining the drainage channel or weir from one contour to the next with stones to avoid or reduce scouring in these locations.
• Step 6: Following, and if possible, during rainfall events, check the stability of the slope, adjusting stone bunds where necessary.
• Step 7: At the end of the rainy season and again following harvest, review the performance of the technology, and prepare for the next growing season.

Switching to no-till or reduced tillage should be planned at least a year in advance so preparations can be made necessary implements can be obtained. Implements should match farm labour availability. You will also need to decide if no till or reduced tillage methods are appropriate based on farm area and desired crops, and start with a small area to determine feasibility. Cereal and legume crops are suitable for no tillage while vegetables and other crops often require some tillage – i.e. reduced tillage.

There are two forms of no-tillage, conventional and organic. Conventional no-tillage includes the application of herbicides to manage weeds, prior to and after planting. Organic no-tillage does not incorporate the use of herbicides, but includes other methods for controlling weeds, including cover crops, crop rotation and free-range livestock. Organic no-tillage is more suitable as it assists mitigate any climate change impacts on the farm.

No till

• Step 1: Prepare fields using conventional (herbicide application) or organic processes include cover crop (Technical Brief 15) and crop rotation (Technical Brief 09).
• Step 2: Test soils – aiming to balance nutrient and pH levels. In the case of acidic soils, add small amounts of lime each year.
• Step 3: Avoid soils with bad drainage, as they become water-logged.
• Step 4: Level the soil surface, removing uneven areas to assist even seed planting.
• Step 5: Eliminate soil compaction.

Reduced Till

• Step 1: This approach is similar to regular tillage, but with significantly less disturbance of the soil. Tilling is only done where needed, and the rest of the soil is undisturbed.
• Step 2: Strip-tillage or zone-tillage involves tilling and seeding in 15 cm strips leaving areas in-between undisturbed.
• Step 3: Ridge-tillage involves preparing ridges post-harvest and letting them settle over time to be planted the next seeding period; with ridges not more than 60 cm apart.

More information of each of these specific practices should be sought prior to implementation.

Crop rotation is a complimentary farming method when practicing no-tillage, as it promotes maximum biomass levels for permanent mulch cover, while controlling weeds (with pre- and post-emergent herbicides), pests, and diseases, as well as improving soil nutrition and fertility.