Neutral

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 implement Zai Pits the following should be carried out:

• Step 1: Zai pits should be dug with a diameter of 30 cm to 40 cm and 10 cm to 15 cm deep. 
• Step 2: Pits should be spaced 70 cm to 80 cm apart resulting in approximately 10,000 pits per hectare.
• Step 3: The farmer should place 2 – 3 handfuls (200 g to 600 g) of organic fertilisers or compost in each pit.
• Step 4: Holes that are dug between planting seasons will trap wind eroded soils, which are fertile and form good soils for plating crops.
• Step 5: It is recommended that 3 tonnes of fertiliser/compost per hectare be available.
• Step 6: Farmers should consider planting crops in these pits prior to periods of rain.
• Step 7: Repeated application of Zai pit technology on an annual basis will increase productivity of degraded land in the long term.

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 undertake deficit irrigation:

• Step 1: Determine critical growth cycle of desired crops.
• Step 2: Experiment with SI strategies to determine critical watering times prior to upscaling.
• Step 3: Strict management is required to determine the level of transpiration deficiency allowable without significant reduction in crop yields.
• Step 4: Farmers capable of implementing deficit irrigation must have access to the minimum required water to implement deficit irrigation.
• Step 5: Farmers must have access to a reliable water source, irrigation systems, including water distribution system, sprinklers and/or drip irrigation system.

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.

To effectively undertake trash lines:

• Step 1: Collect straw, stalks, picked weed or other organic materials from field or surrounding area.
• Step 2: Establish contour lines using method identified in contour planting (Technical Brief 16).
• Step 3: Contour lines for trash lines should be spaced between 5 to 10 m apart.
• Step 4: Heap straw along contour lines on hilly or sloped fields to be approximately 0.5 m wide and up to 0.3 m in height.
• Step 5: Trash should be piled on annually or as the field is prepared. Lines can be maintained for a few years and then decomposed materials can be mixed into the soil.