Skip to main content

Terracing

Value Chain
Annual Average Rainfall
Soils
Topography
Climatic Zone
Water Source
Altitudinal Zone
Decision Making
Farming Characteristics
Mechanisation
Labour Intensity
Initial Investment
Maintenance Costs
Access to Finance/Credit
Extension Support Required
Access to Inputs
Access to Markets
Gender/Youth Smart
Description

Terraces are cross-slope barriers that have been cut into slopes offering surfaces that are flat or slightly sloped. Terraces are designed to minimise erosion and increase the infiltration of runoff water. In addition, terracing allows for a maximum of area for farming and cropping by cutting into slopes, creating steps on a hillside. Riser walls are retained by growing trees or grasses, using stones or compacted soil to manage runoff and ensure stability. Terracing involves significant planning and labour to implement and maintain. Labour should be coordinated and planned to ensure that terracing is not carried out in an ad hoc manner, and labour to maintain the terraces is available annually. Terracing is suited to areas with severe erosion hazards, deep soils, on slopes that do not exceed 25 degrees and are not too stony. Community action is often required, as terracing is a landscape-level solution that can only be implemented if all parties agree and convert slopes together. Implementing individual terraces or terraced sections can negatively impact the entire hillside.

Technical Application

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.

Return on Investment Realisation Period
Crop Production
Fodder Production
Farm Income
Household Workload
Food Security
Soil Quality/Cover
Biological Diversity
Flooding
Crop/Livestock Water Availability
Wind Protection
Erosion Control
Increase Production
Stable slopes are a critical element of maintaining agricultural productivity.
Increase Resilience
Terraces enhance slope stability and reduce soil erosion in the face of changing climates, with changing temperature and rainfall regimes.
Additional Information
PDF File
/sites/secondsite/files/tb/CCARDESATechnicalBrief_18_Terracing_2019-10-17_0.pdf
Benefits and Drawbacks

Benefits

  • Terracing prevents erosion and can act as a rainfed irrigation system.
  • Terracing is a labourious process to implement and takes significant effort to maintain.

Drawbacks

  • Requires professional advice on implementing terracing.
  • If implemented incorrectly, can have negative impacts including more erosion than without terracing.

Agroforestry: Alley Cropping

Annual Average Rainfall
Climatic Zone
Water Source
Decision Making
Farming Characteristics
Mechanisation
Labour Intensity
Initial Investment
Maintenance Costs
Access to Finance/Credit
Extension Support Required
Access to Inputs
Access to Markets
Gender/Youth Smart
Description

Agroforestry is a land management practice that combines the planting and management of trees and shrubs with crops and pasture, providing benefits of soil health, crop yields, resilience to climate change, biodiversity and economic opportunities. Agroforestry encompasses numerous practices, including silvo-pasture, agro-silvo cultural, and agro-silvo-pastural. One successful agro-silvo-cultural practice is alley cropping, where the farmer plants rows of trees, shrubs or hedges between crop rows. Usually hedges comprise leguminous plants intended to fix nitrogen in the soil and provide leaf litter and prunable biomass. The hedges are pruned with the pruned material spread on the ground, to reduce shading and competition with the primary crop. Timing of pruning is important to ensure that the pruned biomass releases nutrients to the soil at a time when the primary crop needs them for maximum crop productivity; e.g. when alley-cropping maize, the pruned biomass needs to breakdown with and release beneficial nutrients into soil from two and eight weeks after planting the maize crop. This approach has proven to be highly successful, with examples in Malawi where gliricidia was alley-cropped with maize where the prunings created a three-fold increase in maize production, which was increased a further 29 % when fertilisers were added. This fertilisation could be achieved with green manure, and other climate smart soil amendment approaches. The space and number of hedge rows to primary crop is dependent upon the field size and the regular growth height of the shrub/hedge. The hedge must not be planted so close that it shades the primary crop. In larger fields, larger deep-rooted timber trees can be planted between groups of rows of primary crop, providing soil benefits, reducing wind-speeds/erosion, and providing timber products.

This approach is considered climate smart as it increases productivity, provides a mechanism for more climate resilient farming, whilst increasing soil carbon levels.

Technical Application

While agroforestry practices are deemed highly beneficial and climate smart, it is important to ensure that proposed practices are appropriate for the specific context – the benefits of the agroforestry practice match the needs of the farmer - and are fit for purpose. Obtain advice from an agroforestry expert before embarking on secondary crop/hedge species selection.

To effectively implement alley-cropping the following should be carried out:

  • Step 1: Clearly understand the objectives of the intervention and identify an appropriate species for intercropping. For maize and sorghum in a smaller subsistence farm setting, selection and growth of hedge rows of a legumes such as cowpea or Gliricidia can provide sustainable benefits in terms of soil quality and secondary fodder/food products. In larger fields, timber trees can be planted every five to ten crop rows, depending on the height of the mature tree, and the shade-tolerance of the crop.
  • Step 2: Identify and understand key conditions, such as prevailing wind direction, and sunlight to ensure that the field is planted in an appropriate configuration, with primary crop and secondary (hedge/shrub/tree) crops planted in such a way as to benefit the primary crop and not compete with it. East to west row orientation should maxmise sunlight, topography permitting.
  • Step 3: For beneficial hedgerow growth with legume species such as Leucaena, cliricidia, and Sesbania sesban, the trees should be planted in rows between two and four metres apart, with individual trees planted as close as possible - between 10 to 15 cm apart. If planted closely, the trees will favour leaves over step growth, creating more mulch to prune for cover. Note that if rows are planted too closely, the secondary crop can dominate the available crop land reducing productivity. Furthermore, the closer the hedges, the more shade will present, which can depress crop growth, and also start to compete for soil water and nutrients, which is not beneficial.
  • Step 4: Once reaching sufficient maturity, after approximately six months (one-metre tall for legumes)– hedges should be pruned to generate mulch for working into the soil. Then the primary crop (maize) can be planted. Pruning once per month thereafter provides cover and ensures that light penetration is maintained. Planting legumes approximately six months before planting the primary crop can ensure that sufficient pruned material is available to incorporate into the soil to enhance growth.
  • Step 5: After harvesting the primary crop, hedgerows can be left to grow taller so that shade reduces weed grown, and to develop material to prune and incorporate into the soil again during the following crop cycle. However, hedges should not be allow to grow too high or dense as their roots will dominate the soil and out-compete primary crops for water and nutrients.

Before implementing any of these technologies, further research may be required beyond the guidance provided here. The World Agroforestry Centre (ICRAF) has many resources, toolkits and success stories that can support such research.

Return on Investment Realisation Period
Crop Production
Fodder Production
Farm Income
Household Workload
Food Security
Soil Quality/Cover
Biological Diversity
Flooding
Crop/Livestock Water Availability
Wind Protection
Erosion Control
Increase Production
Alley cropping and pruning of leguminous hedges increases productivity of primary crops such as maize.
Increase Resilience
Helps farmers to be more resilient to climate change, by sustaining productivity and controlling soil health, especially when faced with changing climates.
Mitigate Greenhouse Gas Emissions
The planting of alley hedge rows of legumes and the introduction of pruned material contributes more carbon to the soil.
Additional Information
PDF File
/sites/secondsite/files/tb/CCARDESATechnicalBrief_17_AgroForestry_2019-10-17_0.pdf
Benefits and Drawbacks

Benefits

  • Trees, shrubs, and hedges are incorporated into farming systems and have many different biophysical and socio-economic benefits.
  • Use of leguminous hedges no only provides pruned materials to provide cover, but they also help fix nitrogen in the soil.
  • Hedges planted in alleys can also provide other benefits such as edible seed pods for human or animal consumption.
  • Hedges and trees can reduce soil erosion from run-off or wind erosion.
  • Alley cropping can provide opportunities for diversified income – selling secondary crops and/or timber.
  • Alley cropped timber trees can provide building materials fire wood.

Drawbacks

  • Initial labour requirements will likely be significant; however, this will be primarily at the earlier stages of the intervention.
  • Ongoing maintenance such as pruning and maintenance of hedges will be needed, although relatively minimal.
  • There may be some costs involved in obtaining hedge seedlings.
  • Use of trees rather than hedges and shrubs introduces more labour, but yields more benefits.

Contour Planting

Value Chain
Annual Average Rainfall
Soils
Climatic Zone
Water Source
Decision Making
Farming Characteristics
Mechanisation
Labour Intensity
Initial Investment
Maintenance Costs
Access to Finance/Credit
Extension Support Required
Access to Inputs
Access to Markets
Gender/Youth Smart
Description

Contour Planting is a planting strategy for sloping fields, where crop rows follow slope contours rather than planting in rows up- and down-slope. The primary aim of this strategy is to slow the downhill flow of water and encourage the infiltration of water into the soil. Slowing the flow of runoff water reduces soil erosion and therefore also nutrient loss.

Contour Ridges are created by tilling, ploughing or hoeing soil to establish ridges along contour lines, acting as a barrier to downhill water runoff and other erosive processes - the higher the ridge height, the more effective the barrier is to preventing soil erosion.

Contour Strips involves use of vegetative barriers e.g. planting of strips of grass or hedges and other species to secure soil and further prevent erosion. These practices are labour intense and require extension support, especially as contour lines are not straight but follow slope characteristics, correctly identifying contour lines is important and can be done using the ‘low-technology’ options that are identified in the Technical Application section of this Technical Brief.

Technical Application

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.
Return on Investment Realisation Period
Crop Production
Fodder Production
Farm Income
Household Workload
Food Security
Soil Quality/Cover
Biological Diversity
Flooding
Crop/Livestock Water Availability
Wind Protection
Erosion Control
Increase Production
Retaining soil structure enables farmers, particularly those planting on sloping fields to maintain productivity.
Increase Resilience
This land management practice aid farmers to maintain soil structure in the face of changing climates and shifting rainfall patterns.
Additional Information
PDF File
/sites/secondsite/files/tb/CCARDESATechnicalBrief_16_ContourPlanting_2019-10-17_0.pdf
Benefits and Drawbacks

Benefits

  • Contour planting prevents erosion on sloped fields and efficiently trap runoff water.
  • Contour planting improved water infiltration and contour ridges improve water retention.
  • Contour planting can be integrated with intercropping contour strips of grass or hedges to help maintain soil structure.

Drawbacks

  • Contour lines are extremely labour intensive and take a significant amount of time to implement.
  • During contour measuring and development, land may be exposed to erosive forces.

Cover Crops

Value Chain
Annual Average Rainfall
Climatic Zone
Decision Making
Farming Characteristics
Mechanisation
Labour Intensity
Initial Investment
Maintenance Costs
Access to Finance/Credit
Extension Support Required
Access to Inputs
Access to Markets
Gender/Youth Smart
Description

Cover Crops are incorporated into farming systems and planted in between growing seasons with the primary purpose of preventing soil erosion and improving nutrient content, and promoting soil quality in general, rather than being planted as a regular food or cash crop. Cover crops can also be utilised for food stuff, fodder or cash crops; but these outcomes are usually secondary to the main aim of improving/retaining soil quality. An additional benefit from growing cover crops is reduction in weed growth, and pests and diseases; increases in water availability in the soil; and increased soil biodiversity. Additional benefits are recognised from cover crops in areas with steep slopes, as the retained plant cover contributes to reducing erosion. Cover crops can be combined with other practices including intercropping practices and erosion control measures to further enhance soil quality and structure. Incorporating cover crops into farming systems increases farmers resilience to climate impacts through improving soils, reducing fossil fuel consumption, and increasing soil carbon sequestering. Extension guidance can be beneficial when selecting relevant cover crops to achieve the above outcomes.

Technical Application

To effectively implement cover crops:

  • Step 1:  Research whether locally available crops (especially legumes) provide potential options for cover crops.
  • Step 2: Establish a demonstration plot could provide farmers with an example of how cover crops function.
  • Step 3: Plant cover crops between primary crop growing systems to improve soil fertility, quality and nutrients.
  • Step 4: Monitor soil structure, nutrient levels, and field integrity to ensure efficacy.
  • Step 5: Incorporate cover crops with other climate smart practices enhance soil, including: Intercropping (Technical Brief 07), Crop Rotations (Technical Brief 09) Reduced/No-tillage Options (Technical Brief 12) etc
Return on Investment Realisation Period
Crop Production
Fodder Production
Farm Income
Household Workload
Food Security
Soil Quality/Cover
Biological Diversity
Flooding
Crop/Livestock Water Availability
Wind Protection
Erosion Control
Increase Production
Cover crops improve soil conditions, providing an enabling environment for agricultural productivity.
Increase Resilience
In changing climates, cover crops can contribute to adaptation strategies, improving soil health.
Mitigate Greenhouse Gas Emissions
Retains and improves soil quality, including carbon sequestration.
Additional Information
PDF File
/sites/secondsite/files/tb/CCARDESATechnicalBrief_15_CoverCrops_2019-10-17_0.pdf
Benefits and Drawbacks

Benefits

  • Cover crops protect soils from erosion and prevent soil nutrient loss.
  • Preventing weed growth, control pests and disease, increase water availability in the soil and increase soil biodiversity.
  • Cover crops may be non-traditional food crops, fodder and/or cash crops.
  • Low cost option for protecting soils and improving soil fertility.

Drawbacks

  • May take time to determine suitable to improve soils.
  • May increase labour demands as new or unfamiliar crops are incorporated into farming systems.

Trash Lines

Value Chain
Annual Average Rainfall
Climatic Zone
Decision Making
Farming Characteristics
Mechanisation
Labour Intensity
Initial Investment
Maintenance Costs
Access to Finance/Credit
Extension Support Required
Access to Inputs
Access to Markets
Gender/Youth Smart
Description

Trash lines are the incorporation of lines of organic materials spread across contours of hilly agricultural fields - strips of heaped straw or weed materials that have been collected during primary cultivation of the land. Trash lines have been found to direct runoff in field and act as an erosion control method. Through decomposition, the trash line material acts as a type of compost adding nutrients to the soil, adding more organic material year on year, should the farmer continue to build this line. This is a climate smart approach as it contributes to soil health, capturing more nutrients and carbon in the soil, and in turn promoting sustainable agricultural productivity. In changing climates, implementation of this practice can contribute to adaptation strategies.

Technical Application

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.
Return on Investment Realisation Period
Crop Production
Fodder Production
Farm Income
Household Workload
Food Security
Soil Quality/Cover
Biological Diversity
Flooding
Crop/Livestock Water Availability
Wind Protection
Erosion Control
Increase Production
Contribute to soil health and therefore agricultural productivity.
Increase Resilience
In changing climates, strategies such as this can contribute to retain and improving soil health.
Mitigate Greenhouse Gas Emissions
Helps retain carbon in soil.
Additional Information
PDF File
/sites/secondsite/files/tb/CCARDESATechnicalBrief_14_Trashlines_2019-10-17_0.pdf
Benefits and Drawbacks

Benefits

  • Low cost option for soil and water conservation on sloped fields.
  • Increase of organic materials in fields.
  • Green manure (Technical Brief 02) production in the field.

Drawbacks

  • Increased workload to implement trash lines but low effort to maintain.

Mulching

Value Chain
Annual Average Rainfall
Climatic Zone
Decision Making
Farming Characteristics
Mechanisation
Labour Intensity
Initial Investment
Maintenance Costs
Access to Finance/Credit
Extension Support Required
Access to Inputs
Access to Markets
Gender/Youth Smart
Description

Mulching is the process of introducing vegetative material to the surface of soil in fields to provide soil cover, reduce evaporation, maintaining an even soil temperature and ultimately improve organic content in soil. These materials can include grasses, crop residues, tree bark and other plant materials, even including seaweed if it is available. These materials should be well decomposed, and mixed well into the top soil when the growing season is over. Mulching improves soil fertility by creating a positive soil environment favouring microbial activity and other promoting beneficial organisms such as earthworms, increases moisture retention, stabilises soil temperatures (protecting soils from both heat and cold), reduces soil erosion and restricts weeds. The temperature control keeps roots and plant bulbs cool in the summer and warm in the winter. It can be utilised on all scales of farm, depending upon the availability of input mulch materials. It is considered a climate smart approach as it sequesters carbon in the soil and promotes soil health which in turn maintains agricultural productivity and the ability of a farmer to adapt to climate changes. In some cases, shredded plastic is sometimes used as a synthetic soil cover, but this is not considered climate smart, as it does not integrate organic matter to the soil, instead introducing plastics.

Technical Application

To effectively undertake mulching the following should be carried out. Tools required: shovel, scissors or shears.

  • Step 1: Gather organic materials from the farm and other external sources if possible. grasses, crop residues, wood chips, tree backs and other plant materials.
  • Step 2: Prepare a location to stock-pile mulch material. A large farm will need a substantial area or pit to achieve this. For smaller operations, mulch can be stored in open-topped barrels and bags punctured for air holes. Storage must allow moisture to contribute to the decomposition process, but no become waterlogged.
  • Step 3: Chop/shred organic material and add to the stock-pile. With larger amounts of material, a motorised, or pedal driven chopper/shredder is useful.
  • Step 4: Allow materials to decompose, but do not leave for extended periods as nutrients and minerals will be lost.
  • Step 5: At the end of the growing season, remove any remaining weeds from the soil surface.
  • Step 6: Spread mulch material over the surface approximately two centimetres deep.
  • Step 7: In firmer or more compacted top soils, lightly work the mulch into the upper soil.
  • Step 8: Lightly water area where mulch has been applied.

Mulch should be applied annually as mulching materials will decompose.

Return on Investment Realisation Period
Crop Production
Fodder Production
Farm Income
Household Workload
Food Security
Soil Quality/Cover
Biological Diversity
Flooding
Crop/Livestock Water Availability
Wind Protection
Erosion Control
Increase Production
Improving soil health through practices such as mulching promotes productivity.
Increase Resilience
In changing climates, with shifting rain patterns, and increasing temperatures, practices such as mulching help retain soil health.
Mitigate Greenhouse Gas Emissions
Mulching provides soil cover, promoting retention of carbon in the soil, and also introducing organic content to the soil itself.
Additional Information
PDF File
/sites/secondsite/files/tb/CCARDESATechnicalBrief_13_Mulching_2019-10-17_0.pdf
Benefits and Drawbacks

Benefits

  • Mulching improves soil structure, fertility and quality, stabilising soil temperature and retaining moisture.
  • Mulching can increase nutrient content in the soil.
  • Mulch can contribute to reducing soil erosion.
  • Mulching contributes to preventing weeds from growing.
  • If not used, mulch can be sold to other farmers.

Drawbacks

  • Despite positive benefits, requires substantial labour inputs, hence the need for on-farm labour resources, or the ability to hire.
  • Mulch can spoil if not managed correctly.
  • Considerable quantities of mulch are needed to cover fields.
  • Again, if not managed correctly, can harbour pests, diseases and weeds (seeds).
  • If over-applied, can result in a toxic environment.

Erosion Control

Value Chain
Topography
Climatic Zone
Water Source
Decision Making
Farming Characteristics
Mechanisation
Labour Intensity
Initial Investment
Maintenance Costs
Access to Finance/Credit
Extension Support Required
Access to Inputs
Access to Markets
Gender/Youth Smart
Description

Erosion control measures are practices designed to reduce runoff water and wind erosion that wash away top soil and nutrients, degrading soil biodiversity and reducing agricultural productivity. Erosion is a natural, biophysical process resulting from rainfall, water flows, wind, or storm runoff. Erosion is integral to the formation of soils, however human and animal activity, including agriculture and clearing of land, can accelerate erosive processes, drastically impacting landscapes, soils (e.g. quality) and watercourses. In addition, erosion control measures can contribute to reducing rainfall runoff, increased water infiltration into the soil, and attenuates flooding. The intensity of rainfall is directly correlated with the severity of soil erosion; hence, this is a significant problem across the Southern African region as much of the rainfall in the region is episodic, and intense. To prevent or reduce erosive processes control measures can be incorporated into farming systems to reduce or reverse degradation and potentially restore or improve soil quality. Erosion control measures aim to mitigate soil erosion and improve soil fertility by reducing flow and speed of run-off to avoid soil being washed away. Erosion control can be initiated through a number of interventions, including, but not limited to, intercropping (e.g. planting cover crops), mulch, conservation tillage and reforestation, as well as terracing, soil bunds, etc.. Example: Stone Bunds. Lessons learned from West Africa show that stone bunds constructed along contour lines in fields and in key run-off locations can significantly reduce run-off, particularly in steeper agricultural fields. The stone lines reinforce the soil structure in the field following the contours of the land, reducing the speed and volume of run-off, thereby reducing the likelihood of erosion. This is an appropriate technology to implement on slopes up to 15 to 20 degrees. This is considered a climate smart practice as it maintains soil structure and nutrients, in turn retaining carbon in soil, enabling farmers to adapt to climate changes and sustain agricultural productivity.

Technical Application

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.
Return on Investment Realisation Period
Crop Production
Fodder Production
Farm Income
Household Workload
Food Security
Soil Quality/Cover
Biological Diversity
Flooding
Crop/Livestock Water Availability
Wind Protection
Erosion Control
Increase Production
Increased water infiltration can extend growing period and mitigates short dry spells. Can reduce flood risk downstream.
Increase Resilience
Increased production due to improved nutrient availability and higher nutrient use efficiency.
Mitigate Greenhouse Gas Emissions
Depending on practices used, may lock more carbon into the soil.
Additional Information
PDF File
/sites/secondsite/files/tb/CCARDESATechnicalBrief_11_ErosionControl_2019-10-17_0.pdf
Benefits and Drawbacks

Benefits

  • Erosion control measures prevent the loss of top soils and nutrients.
  • Can help farmers adapt to changes in climate that have include increased rainfall amounts and intensity.
  • Can reduce the impact of wind erosion.

Drawbacks

  • Erosion is a natural process that can be increased due to human and animal activity.
  • Requires substantial labour inputs to construct bunds and other erosion control measures
  • Maintenance is also needed.

No Tillage

Value Chain
Annual Average Rainfall
Soils
Climatic Zone
Water Source
Decision Making
Farming Characteristics
Mechanisation
Labour Intensity
Initial Investment
Maintenance Costs
Access to Finance/Credit
Extension Support Required
Access to Inputs
Access to Markets
Gender/Youth Smart
Description

No-tillage or reduced-tillage farming involves growing crops without ploughing or reducing the use of machinery in preparing fields for planting. Excessive tillage can have major impacts on soils and the environment including loss of organic matter and soil organisms, increased soil erosion and pesticide runoff, reduced soil fertility, loss of soil structure, etc. Thus, implementing no- or reduced-tillage can help farmers in conserving soil quality and in many cases, increase crop production.

In implementing no-tillage processes, land is not or is minimally disturbed and crop residues are normally left on the soil surface with minimal use of implements. Reduced tillage practices include technological changes such as using more efficient ploughing tools and/or implementing strip-till, zone-till or ridge-till processes. Most reduced tillage systems are implemented in conjunction with cover crops and mulches to protect soil structure.  Tilling by hand or animal means are considered reduced tillage methods.

The adoption of no or reduced tillage practices reduces the amount of fossil fuels consumed by farmers and increases carbon sequestration as soil carbon is not exposed or released in the atmosphere and is thus a climate smart practice.

Technical Application

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.

Return on Investment Realisation Period
Crop Production
Fodder Production
Farm Income
Household Workload
Food Security
Soil Quality/Cover
Biological Diversity
Flooding
Crop/Livestock Water Availability
Wind Protection
Erosion Control
Increase Production
Improved soil structure and increased microbial and invertebrate activity in the soil makes nutrients more available to plants.
Increase Resilience
Increased water infiltration and soil biodiversity mitigates the effects of short-term dry spells.
Mitigate Greenhouse Gas Emissions
Locks more carbon in the soil. Reduced ‘passes’ in mechanised systems reduces fuel inputs required.
Additional Information
PDF File
/sites/secondsite/files/tb/CCARDESATechnicalBrief_12_No%20Tillage_2019-10-17_0.pdf
Benefits and Drawbacks

Benefits

  • Increased soil fertility, organic matter and soil structure, and beneficial organisms (earthworms, etc).
  • Reduced compaction of soils.
  • Prevention of soil erosion.
  • Reduction in fossil fuel consumption.
  • Increased soil carbon sequestration.

Drawbacks

  • A positive response can be delayed for up to three years.
  • Effective weed management may require the application of herbicides.
  • Possible decreases in crop productivity if not carried out effectively.

Relay Cropping

Value Chain
Climatic Zone
Water Source
Decision Making
Farming Characteristics
Mechanisation
Labour Intensity
Initial Investment
Maintenance Costs
Access to Finance/Credit
Extension Support Required
Access to Inputs
Access to Markets
Gender/Youth Smart
Description

Relay cropping is a form of intercropping where two or more crops are grown simultaneously during part of their life cycles. Intercropping often involves maize and legumes, which increases nitrogen fixing in soils and increased biomass production. The second (or succeeding) crop is planted after the reproductive stage (flowering) of the existing crop but before harvesting. Some of the advantages of relay cropping include better erosion control due to crop cover, reduced spreading of pests and diseases, and crop diversification, plus general soil health. As an added benefit, it mitigates the emission of greenhouse gases through reducing nitrate leaching and increasing carbon sequestration. There is also potential socio-economic benefits for farmers as in many cases relay cropping increases crop productivity.

However, this form of intercropping is not easily implemented in large-scale agricultural systems due to complications in weed control and challenges associated with operating mechanised equipment on fields with relay cropping.

Technical Application

To effectively implement relay cropping, the following steps should be carried out:

  • Step 1: Test/experiment with locally available crops to determine if they are complementary and can grow concurrently - cereal crops and legumes are complementary and can generally grow concurrently.
  • Step 2: Prepare land through clearing, weeding and a no-tillage approach (Technical Brief 12).
  • Step 3: Plant cereal crop first according to normal planting season schedule –during rainy season. Space this cereal crop 70 cm by 50 cm apart.
  • Step 4: Prior to cereal harvest, plant the legume crop between cereal crop rows with spacing based on legume planting efficiencies (researched prior to planting for optimum growth).
  • Step 5: After cereal has been harvested, bend the dried stalks down to provide more ground cover.
  • Step 6: When legumes are ready for harvest, collect the productive pod/seed/bean/nut and leave the stalk uprooted in the field to maximise ground cover.
Return on Investment Realisation Period
Crop Production
Fodder Production
Farm Income
Household Workload
Food Security
Soil Quality/Cover
Biological Diversity
Flooding
Crop/Livestock Water Availability
Wind Protection
Erosion Control
Increase Production
More efficient use of available resources. Increased yield from the same field.
Increase Resilience
If legume – maize/sorghum relays are employed the risk of crop loss is reduces and dietary diversity is enhanced.
Mitigate Greenhouse Gas Emissions
Helps lock more carbon in the soil.
Additional Information
PDF File
/sites/secondsite/files/tb/CCARDESATechnicalBrief_08_RelayCropping_2019-10-17_0_0.pdf
Benefits and Drawbacks

Benefits

  • Increased and diversified crop yield.
  • Improved soil quality preventing leaching, and introducing nutrients.
  • Increased land cover reducing erosion and improving carbon capturing.
  • Food security/farm income increase.

Drawbacks

  • Weeding makes this approach labour intensive, and planting and harvesting can become less efficient. This requires consideration, especially if women’s workload increases as a result.
  • Carried out precisely to ensure crops are compatible, planting is undertaken at correct times and harvesting is low impact to avoid crop damage.
  • Possible competition between plants for nutrients, water, space, etc.

Intercropping

Value Chain
Climatic Zone
Water Source
Decision Making
Farming Characteristics
Mechanisation
Labour Intensity
Initial Investment
Maintenance Costs
Access to Finance/Credit
Extension Support Required
Access to Inputs
Access to Markets
Gender/Youth Smart
Description

Intercropping is a process of growing multiple crops either together or in proximity to each other on one piece of land, thereby improving crop production, reducing and preventing land degradation and increasing crop output.

There are different methods of intercropping:

  • Mixed intercropping – two or more crops are seeded together and harvested together.
  • Row/strip intercropping – two or more crops planted on the same field but planted in alternate rows.

Crops selected for intercropping should not have similar properties or compete but should be selected to complement one another and be mutually beneficial. For example, deep rooted crops can be intercropped with shallow rooted crops, so as to not compete for water or nutrients. Intercropping helps achieve ecological benefits not possible with monocropping systems. Intercropping is commonly practiced for maize-legume systems, where legumes introduce nitrogen into the soil benefiting maize production and improving soil fertility during crop growth. Furthermore, the legume crops can be utilised for fodder for livestock. This practice is particularly beneficial for smallholder farmers, who can grow multiple crops on small plots to receive multiple benefits including improving production/yields, and increasing household food security. Intercropping is also a climate-smart practice as it mitigates farmer risk to climate variations, through diversifying and increasing crop production, reduces threats of pests and disease, and increases carbon sequestration in soils and biomass production.

Technical Application

To implement intercropping practices:

  • Step 1: Consider soil properties - has the soil been mono-cropped and/or is it leached?
  • Step 2: Consider crop characteristics – will crops be competing for nutrients, water space, sunlight or will they be mutually beneficial adding nutrients
  • Step 3: Prepare land through clearing and weeding. A no-tillage approach is recommended – see Technical Brief 12.
  • Step 4: Select whether the farmer should undertake Mixed Intercropping (Good for smaller plots however plants compete) or Row/Strip Intercropping (crops less likely to compete). See also KP07 – Climate Smart Planting Options for Maize and Sorghum.
  • Step 5: If mixed intercropping is selected, sow two crops simultaneously mixing seeds to together while planting. Harvesting may not be a simultaneous process as different crops have different growth rates and seasons.
  • Step 6: If row/strip intercropping plant two or more crops in the same field but in separate rows patterns. Rows should be spaced 50 cm apart and can have a row of 1:1 or 2:1 ratio of cereal crop to legume.
  • Step 7: Harvest as individual crops require, be careful not to disrupt other crops that have not yet matured.
Return on Investment Realisation Period
Crop Production
Fodder Production
Farm Income
Household Workload
Food Security
Soil Quality/Cover
Biological Diversity
Flooding
Crop/Livestock Water Availability
Wind Protection
Erosion Control
Increase Production
Higher levels of production from the same area of land, due to healthier soils.
Increase Resilience
Reduces losses due to pests and diseases and can mitigate losses due to drought as they increase organic matter, with increased water holding capacity and stimulated bacterial growth.
Mitigate Greenhouse Gas Emissions
Helps lock more carbon in the soil and plants.
Additional Information
PDF File
/sites/secondsite/files/tb/CCARDESATechnicalBrief_07_Intercropping_2019-10-17_0.pdf
Benefits and Drawbacks

Benefits

  • Increased and diversified crop yield.
  • Food security/farm income increase.
  • Nutrient fixing.
  • Food security/farm income increase.

Drawbacks

  • Competition between plants for nutrients, water, space, etc.
  • Increase farmer workload as weeding, planting and harvesting are less efficient. Requires consideration especially if women’s workload increases as a result.
Subscribe to Positive

Funding Partners

4.61M

Beneficiaries Reached

97000

Farmers Trained

3720

Number of Value Chain Actors Accessing CSA

41300

Lead Farmers Supported