Indigenous soil and water conservation methods in Africa.

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Indigenous soil and water conservation methods in
Africa.

• Presented by
• Becky Humphrey
• (MSc Water Resources)

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Introduction

• What is indigenous knowledge?
• The knowledge used by local people to make a
  living in a particular environment.
• A body of knowledge built up by a group of
  people through generations of living in close
  contact with nature.

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Indigenous knowledge is based on

• Adapting to the specific requirements of local
  people.
• Creating and experimenting with methods to suit
  local environmental conditions.
• The incorporation of outside influences, together
  with inside innovations.
• Cultural knowledge
• Consideration of social, political, economic and
  spiritual aspects of the local lifestyle.

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Soil and Water Conservation

• Need to take holistic approach in dealing with
  any aspect of environmental conservation.
• Soil processes and runoff processes affect each
  other, therefore it makes sense to use methods
  which incorporate both factors.

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Types of SWC methods

• Earth / stone bunds
• Bench / step terraces
• Improved planting pits
• Micro basins
• Pitting
• Modification of contour ridges
• Mulching
• Contour stone bunds
• mounds

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Types of SWC methods (continued)

• Strips
• Vegetation barriers
• Grass strips
• Drainage ditches
• Basin irrigation
• Ridge cultivation
• Raised bed cultivation
• Hedge barriers

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Focus on Africa

• Long history of traditional farming methods.
• Diverse landscape between within individual
  countries.
• Inhospitable terrain.
• Harsh climatic extremes.
• Usually very hot and dry, but problem of flash
  floods during rainy season also exists.

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Case Studies

• The Dogon Plateau, Mali
• Southern Zimbabwe
• Upper East Region, Ghana
• Harerge Highlands, Ethiopia

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Traditional SWC techniques on the Dogon Plateau,
Mali.

• Area Characteristics
• Agricultural economy (cereal cultivation market
  gardening)
• Subsistence farming with limited cash crops
• Main crops are Sorghum Millet
• Main garden crops are onions tomatoes
• Rainfall low variable

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Problems

• Droughts lead to poor crop production
• Heavy rainfall leads to severe soil erosion and
  pan formation
• Soil has poor structure
• Steep hillsides
• Area densely populated
• Only 10-15 of plateau is arable land

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Development of indigenous methods

• Hillsides originally populated because Dogon
  people hid from invaders in caves
• Despite the fact that this is no longer an issue
  and good arable land exists elsewhere, population
  is concentrated here because of traditional
  values and cultural reasons
• SWC necessary for survival

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Traditional SWC techniques

• Cones / mound making
• Terracing of fields and hillsides
• Stone lines
• Bunds / low stone walls
• Square basins
• Planting holes

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More unique methods

• Stalks left after harvest are cleared away and
  then laid on the soil surface in bands to reduce
  soil erosion.
• When the organic matter eventually decomposes it
  provides another benefit through increased soil
  fertility due to added nutrients

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The Future

• Labour shortages due to migration are threatening
  SWC techniques
• Land tenure problems
• However, increasing role of women assistance
  through participatory development is promising.

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Indigenous SWC in Southern Zimbabwe

• SWC has played important role in development of
  smallholder agriculture.
• Long tradition of indigenous farming methods
  threatened by mechanisation and political
  intervention

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Historical SWC

• Farming based on livestock shifting cultivation
• Livestock food, clothing, transport manure
  (also social status) but not enough draught
  power.
• Main crop was Finger Millet.
• Bush clearance led to cultivation of 3-10 yrs,
  then fallow.
• Wetlands also cultivated (ideal during drought)
• Hunting gathering
• Traditional values ensured conservation (esp.
  water trees)
• Low population limited tools
• Use of intercropping, mulching, bunds ridges.

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The Plough

• Plough introduced by white settlers in late 19th
  century
• Adopted by local farmers on large scale 1920-1940
• Indigenous farming saw many benefits in increased
  production
• Erosion occurred on large scale (rills gullies)
  land took longer to recover from fallow.

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Government Intervention

• 1930 onwards erosion became serious problem
• Colonial government forced building of contour
  ridges and lowering of stocking rates
• Also prohibited wetland use
• Unpopular, esp. as ridges unsuitable for dry
  climate
• Shifting cultivation bush fallow ended
• Use of plough encouraged
• Poorly constructed ridges increased gully erosion

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The Liberation Struggle

• 1976-1980 liberation struggle
• Farmers encouraged to abandon ridges
• New government could not enforce SWC
• Farmers associated SWC with ridge building
  therefore opposed to SWC
• Village development committees established
• Gradually, need for SWC realised

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Problems

• Attitude based on historical contempt for local
  knowledge in favour of Western mechanisation
• Previous indigenous SWC methods inappropriate due
  to increased population density
• Confusion over land rights

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Solutions for the future

• 2 projects Food Security Conservation Tillage
• Incorporation of traditional SWC methods
• Participatory approach has led to encouraging
  response
• Membership of farmer clubs increased
• Particular interest in garden crops SWC

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The Yaba-itgo system in Upper East region, Ghana

• Area characteristics
• Savannah grassland belt
• Erratic rainfall May-September, but often lull in
  growing season
• Dry dusty winds during dry season
• Sandy soil with little OM
• Rain fed crops (millet), subsistence farming
• Garden crops during dry season
• Small livestock

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Problems

• Farmers cannot afford livestock equipment for
  ploughing
• Renting land discourages SWC
• Women deterred from SWC, despite being good at it
• Isolation during rainy season
• Exploitation by middle men
• External intervention usually abandoned by
  farmers

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Yaba Itgo Grandfathers way of doing

• Wide range of SWC methods
• Usually aim to conserve moisture on steep slopes
• Also encourage runoff if area prone to flooding
• Methods never used in isolated way
• Clear division of labour between gender and age

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Erosion Control

• Dependant on household labour availability
• Stone bunding
• Contour tillage
• Border grasses
• Strip cropping
• terracing

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Drainage control

• Dependant on communal labour availability
• Focus on flood risk due to cash crops
• Land smoothing / levelling
• Graded furrows

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Recent Changes

• Driving force changed from cultural reasons to
  production incentives
• SWC blended with agronomic practices e.g. mixed
  cropping, cultivation of groundnuts, mulching
• Bush burning greatly reduced, so soil fertility
  improved
• Some incorporation of live fencing use of
  livestock for ploughing (opposed still by women)

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Indigenous SWC techniques of the Harerge
Highlands, Ethiopia

• Area characteristics
• Hilly terrain (low-moderate relief) interspersed
  with sloping valleys
• High population density
• Stony soil, rocky outcrops
• Erratic rainfall regime (2 seasons)
• Erosive tropical storms

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Problems

• Lower more unreliable rainfall
• Decline in soil fertility
• Shortage of fertilizer (organic inorganic)
• Shortage of livestock for ploughing
• Prevalence of pests disease
• Migration of farmers to urban areas

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Traditional SWC methods

• SWC methods have increased due to decline in
  agricultural productivity
• Use wide range of agronomic, biological
  mechanical measures
• Knowledge has evolved over time in response to
  local needs
• Crop rotation, intercropping, cactus / grass
  strips
• Focus on increased soil fertility, reduced
  erosion diversification

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Stone bunds

• 3 benefits
• Remove stones from field, easier to plough
• Slows runoff traps moisture
• Stops erosion traps nutrients
• Soil bunds also used
• Not as stable but easily moved / rebuilt
• Can evolve into terraces if left to mature

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Outside intervention

• Development programs have gone wrong
• Farmers not consulted
• Large scale engineering as opposed to gradual
  build up when needed
• Livestock / human passage ignored

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Disadvantages of traditional SWC

• Most methods require a high level of manpower,
  but many younger members of families are leaving
  rural locations in search of more prosperous
  employment
• Often cannot be carried out on a large scale
• Need for some inclusion of modern methods

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Advantages of indigenous SWC

• Local people have managed the land for
  generations and know what is needed
• Low cost
• Simple methods that can be learned quickly

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Conclusions

• Indigenous methods of SWC are long established
  and work well
• However, their success is largely affected by
  political factors and intervention by developed
  countries, NGOs etc.
• There is an ever increasing need for cooperation
  and understanding between researchers, engineers,
  local farmers etc.
• Some cultural traditions gender issues need to
  evolve in order for indigenous SWC to survive in
  Africa.

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The importance of indigenous knowledge

• Incorporating indigenous knowledge into research
  projects can contribute to local empowerment and
  development, increasing self-sufficiency and
  strengthening self-determination.