Monday 23 April 2018

CONSERVATION AGRICULTURE: THE ONLY HOPE LEFT FOR FOOD SECURITY


Conservation Agriculture was first defined during the First World Congress on Conservation Agriculture (1-5 October 2001)

It is a set of soil management practices that minimize the disruption of the soil's structure, composition and natural biodiversity. CA has proven potential to improve crop yields, while improving the long-term environmental and financial sustainability of farming.

Put differently, CA is an approach to managing agro-ecosystems for improved and sustained productivity, increased profits and food security while preserving and enhancing the resource base and the environment.
Credit: courtesy

According to the UN Environment official, studies show that nature based agriculture can increase yields by up to 128 percent under the changing climate to enhance food security. More here

This is opposed to conventional farming practices, whereby farmers remove, burn crop residues or mixes them into the soil with a plough or hoe. As a consequence, the soil is left bare, so it is easily washed away by rain, or is blown away by the wind



Conservation Agriculture Potentials

CA holds tremendous potential for all sizes of farms and agro-ecological systems, but its adoption is perhaps most urgently required by smallholder farmers, especially those facing acute labour shortages. It is a way to combine profitable agricultural production with environmental concerns and sustainability and it has been proven to work in a variety of agro-ecological zones and farming systems.


Conservation Agriculture makes sustainable and rural development practicable through its integration of crop bio-diversity, mixed crop/livestock farming, and other activities, all characterized by efficient use of resources. This results in a more productive agriculture, which improves food security and rural livelihoods.

The many economic, social and environmental benefits of Conservation Agriculture justify a fundamental re-appraisal of conventional farming methods. And conservation Agriculture should be considered as a theme which cuts across various disciplines, organizations and ministries.

According to FAO (Food and Agricultural Organization of the United Nations), Conservation agriculture (CA) aims to achieve sustainable and profitable agriculture and subsequently aimes at improved livelihoods of farmers through the application of the three CA principles: minimal soil disturbance, permanent soil cover and crop rotations.

Aims  -

To  pursue  more  sustainable  agriculture and rural development through the application of three  major  principles:  minimal  or  no  soil disturbance,  permanent  soil  cover  and  crop rotations.

It emphasizes that:

      Soil is a living body
      Importance of 0-20cm of soil as the most active zone and most vulnerable to erosion and degradation
      Essential to quality of life on the planet

It seeks to preserve soil composition, structure, natural biodiversity and sustainable food production through:

·         Utilization of green manures/cover crops (GMCC's) to produce the residue cover;
·         No burning of crop residues;
·         Integrated disease and pest management; using IPM bags
·         Controlled/limited human and mechanical traffic over agricultural soils

NOTE: Organic farming involves growing crops and livestock without using agrochemicals. It is possible to do Conservation Agriculture in an organic way (without using fertilizers, herbicides or pesticides), but many types of conservation agriculture use these agrochemicals - but in small amounts and with care.

Major Principles/Characteristics of Conservation Agriculture

  1. Continuous minimum mechanical soil disturbance,(just enough to get the seed into the ground) 
  2. Permanent  organic soil  cover 
  3. Crop rotations (Diversification of crop species grown in sequences and/or associations.)

1.      Continuous Minimum/No Soil  Disturbance

This done through  minimum  or  zero  tillage (direct seeding)
Zero tillage aims to enhance and sustain  farm  production  by  maintaining  a permanent  or  semi-permanent  organic  soil  cover that protects the soil from sun, rain and wind and allows soil micro-organisms and fauna to take on the  task  of  "tilling"  and  soil  nutrient  balancing. Farmers  can save their labor time and fuel costs

Advantages of Continuous minimum mechanical soil disturbance

      The crop residues remain on the soil surface and produce a layer of mulch. This layer protects the soil from the physical impact of rain and wind
      It stabilizes the soil moisture and temperature in the surface layers.
      The zone becomes a habitat for a number of organisms, from larger insects down to soil borne fungi and bacteria. These organisms macerate the mulch, incorporate and mix it with the soil and decompose it so that it becomes humus and contributes to the physical stabilization of the soil structure.
      At the same time this soil organic matter provides a buffer function for water and nutrients.
      Larger components of the soil fauna, such as earthworms, provide a soil structuring effect producing very stable soil aggregates as well as uninterrupted macropores leading from the soil surface straight to the subsoil and allowing fast water infiltration in case of heavy rainfall events.

2.      Permanent Organic Soil  Cover.

      Keeping the soil covered and planting through the mulch will protect the soil and improve the growing environment for the crop 
      Permanent  soil cover needs to be integrated into farming systems to  obtain  additional  benefits. 
      Crop  residues  will not  be  burnt  since  they  are  made  part  of  the permanent  soil  cover,  and  air  pollution  will  thus be  reduced. 
      Residues from previously planted crops, other cover crops, and  green  manure  cover  crops  are  utilized  for permanent or semi- permanent organic soil cover.
      The  dead-residue  biomass  of  the  cover  crops functions as mulch, protecting the soil physically from  sun,  rain  and  wind. 
      Soil  mulch  reduces water evaporation, conserves moisture, and helps moderate  soil  temperature,  making  conditions more  hospitable  for  below-ground  biota.
      Mineralization  and  nutrient  losses  are  reduced, and more satisfactory levels of organic soil matter are built up and maintained.

3.      Regular Crop Rotations. (Diversification of crop species grown in sequences and/or associations) to help combat the various biotic constraints:
  • Which include nitrogen-demand crops such as cereals growing in rotation with atmospheric nitrogen-fixing legumes and/or Cruciferae.
  • Help control pests, diseases, weeds and other biotic  factors. 
Well-balanced  crop  rotations  can neutralize  many  of  the  possibly  negative  aspects of minimum/no-tillage,  such  as  pest  build-up,  as they  increase  the  diversity  of  favorable  insects and  organisms  that  can  help  maintain  checks  on the spread and impact of pests and diseases.

 Tools Used in CA


1. Jab planter

2. Mulch planter
3. Shallow weeder
4. Traditional hoes, panga,
5. And using a special herbicide that kills only weeds and has no chemical adverse effect on the microbes. Stays in the soil for only three days. It is called WOUND OUT.

Benefits offered by Conservation Agriculture

It brings socio-economic  benefits  to farmers  and  ecological/environmental benefits  to  climate  change  mitigation:
      Increased  profit  with  decreasing  inputs  of labour,  time,  farm  power  and  fuel consumption
      Improved long-term  productivity  and  more stable yields
      Reduced soil erosion - Soils under CA have very high water infiltration capacities reducing surface runoff and thus soil erosion significantly
      Increased  organic  matter  and  improved  soil fertility/health
      Recharge of the aquifers  through  improved water infiltration
      Decreased soil compaction 
      Better traffic ability in the field through Controlled  Traffic  Farming  (CTF) or Permanent  Raised  Beds  (PRB)
      Reduced air pollution through reduced release of carbon gases and nitrous oxides No till fields act as a sink for CO2
      Increased carbon sequestration
      More micro biota and improved biodiversity

Where to Practise Conservation Agriculture

Conservation agriculture can be used in all parts of Africa, except where it is too dry to grow crops. It can be applied in various climatic zones and under different conditions, though it may look very different from place to place. 
  • In semi-arid lands, conservation agriculture retains water in the soil, keeps the soil temperature even, and protects the land from erosion during heavy downpours. Maintaining soil moisture is the main challenge in these areas, so rainwater harvesting methods can be very useful to increase the amount of water available for crops. 
  • In sub-humid and humid areas, weeds and erosion are likely to be more of a problem. Crops are planted at closer spacings, and cover crops help suppress weeds and protect the soil. 
  • On slopes, conservation agriculture can be used in association with terraces, contour grass strips and other erosion-control methods. 
  • Where labour is scarce, perhaps because of HIV/AIDS, conservation agriculture enables farmers to produce good yields with less labour. 
  • In densely populated areas, conservation agriculture increases yields on small plots of land under intensive cultivation. 
  • On good soils, conservation agriculture keeps the soil healthy and maintains yields.
  • On poor soils, it is a good way to rebuild soil fertility and enhance water-holding capacity, so increasing production.
Implementation of Conservation Agriculture

Conservation agriculture has been successfully implemented in both small-scale (Sorrenson et al., 2001) and large-scale (FAO, 2000e) farming, where it has given economic benefits as well as improved water resources. CA is therefore based on enhancing natural biological processes above and below the ground. More reading here


State of Conservation Agriculture in Kenya


During the  Second National Conservation Agriculture Conference, Nairobi, Mr Ruto, The Deputy President, Kenya, said in order to reap the dividends of Conservation Agriculture, we need to have a minimum of 10 percent of farmers countrywide to adopt the practice, saying county governments were perfect partners in ensuring the success of the programme





Photo credit: DP press

Mr Ruto challenged the Ministry of Agriculture and Irrigation to formulate sound policies and a viable implementation framework so as to anchor the approach to sustain productivity. 


Jeniffer Muthoni Maina has one acre farm in Kibubung’i location in Laikipia East sub-county which she grows maize, black beans (njahi) and dairy farming.




Until 2013, Muthoni could only harvest half a bag or one bag of 90kg maize from her one acre farm. She said, with these yields, she could hardly make ends meet for her family of four children.


Muthoni says that through the CA, she has been able to reduce on labour costs which would add up to her spending about Ksh3,000 monthly. Read more here


Case study of CA in Kenya


Constraints and limitation towards adoption of CA

      Lack  of  knowledge  and  information : - Information  has  to  be relevant, factual, locally appropriate, and useful in order to generate mindset change among farmers.
      Lack  of  direct  seeding  implements  for  planting into the permanent soil cover (In order to implement  CA,  the minimum a farmer needs is a zero-tillage planter.) CA will reduce machinery  sales,  particularly  of large  tractors.  The cost-effective  and  efficient direct  seeding  machines  suitable for developing countries
      Inadequate institutional support, 
      The  farmer’s attitudes toward CA and farmer’s  mindset  that  favors  the  status  quo ontillage and the fear of failure.

Policy recommendations 

       An  institutional  framework  of  government services  to  mainstream  sustainable agriculture development and GHG mitigation into  national  policies,  laws,  investment strategies,  education  and  extension programmes;
        Raise  public  awareness  to  facilitate  the extension  of  CA  techniques  by  full involvement  of  all  concerned  stakeholders, including  farmers,  researchers, technicians, extension specialists and agronomists;
        Enhanced  research  and  manufacturing  of suitable direct seeding implements    supported by both public and private sectors;
        Sharing  of  knowledge  about  all  aspects  of minimum/no-tillage  system  by farmers, researchers,  technicians  and  extension specialists;
        Demonstration of good practices to promote farmers’  mindset  change  toward minimum/no-tillage CA;
      Subsidies  for  buying  new  implements  and phasing out of the old ones;
        Policy on financing the application of Clean Development Mechanism (CDM) in agricultural sector;
        Promote  the  public-private  partnership  in financing  of  the  CDM  application  to  the agricultural sector.




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