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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.

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.

In addition to agricultural inputs and the following technical implementation steps, ISFM requires the farmer to consider farm size (land area), and property rights (land tenure) to ensure that investments are efficient and sustainable.

To implement ISFM approaches, the following should be considered:

• Step 1: Prepare a needs assessment based on understanding of farm challenges – low or declining productivity, soil fertility, low organic content, etc
• Step 2: Measure fields that require attention to understand volumes of inputs required.
• Step 3: Develop (or update) an agricultural calendar to use as a platform for discussion between farmer(s) extension officer(s).
• Step 4: Develop plan and schedule/programme of locally appropriate ISFM interventions between farmer(s) and extension officer(s), obtaining guidance from agricultural suppliers where necessary (lime application, etc). As ISFM is a blended approach, the plan should consider short and medium to long term interventions and outcomes.
• Step 5: Examine cost implications of the plan, revising where necessary based upon available resources, and if necessary/available apply for credit to fund investments.
• Step 6: Assess labour requirements within the ISFM plan to ensure that they can be fulfilled, and considerations of gender and youth have been accommodated – women are not expected to do the majority of work, and children are not missing school.