Problem Cause Possible Solutions
A. Low soil i) Nutrient Inorganic fertilizers
fertility deficiencies or Fertilizer placement
imbalances Split fertilizer applications
Opportune timing of fertilizer application
Non-acidifying fertilizers increase nutrient availability Inorganic foliar fertilization Rock phosphates
FYM Composts Guano
Addition of crop residues or forest litter
Incorporation of green manures Legume rotations1
Legume intercropping Fallows
Enriched fallows ii) Low nutrient retention
capacity
Split applications of inorganic fertilizers
Organic manures Composts
Incorporation of plant biomass Leave crop residues and zero tillage2 Cover crop fallows
iii) High leaching Deep rooting perennial crops
losses of nutrients Alley cropping
Dispersed trees in annual crops Dispersed trees in pastures Tree-enriched fallows
iv) Erosion of Leave crop residues
topsoil Zero tillage
Mulches
Higher plant density Cover crops Covered beans Intercropping
1 Legume inoculartion may be necessary.
2 Controlled grazing of residues, live fences, hay or silage production, improved pasture species and better management of existing pastures may be required to enable the residues to be left in the field.
Problem Cause Possible Solutions
Sequential and relay cropping Weed control with herbicides Controlled grazing
Trash lines
Vegetative cross-slope barriers Contour sowing, tillage and weeding Minimum tillage
Strip tillage
Tillage to break up surface crusts Tillage at the end of the rains
Deep till to loosen impermeable layers Stone lines
Stone bunds Fanya juu terraces
Bench, orchard and platform terraces Diversion canals
B. Low crop i) Low crop yields Improved varieties
productivity Crop diversification
ii) Extensive use of Higher plant populations3
land Intercropping
Sequential and relay cropping Alley cropping
Kitchen gardens
iii) Poor quality Improved seed selection
seed Seed treatment
iv) Weeds Herbicides
Semi-botanical herbicides Integrated weed management Crop rotations
Spreading crops such as Cucurbitaceae
Cover crops
v) Pests or diseases Integrated pest management
Inorganic pesticides Natural pesticides Insect traps
Insect-repellent crops Crop rotations
vi) Adverse micro- Shade trees
climate Wind breaks
See I iii and iv
vii) Low fertility See A
C. Presence of i) Aluminium or Acid-tolerant species
toxic substances Manganese Acid-tolerant varieties
toxicity Lime or dolomitic limestone
Gypsum application
Gypsum and lime application
ii) Iron toxicity Drainage
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Problem Cause Possible Solutions
iii) Salinity Leaching
Drainage
iv) Sodium Gypsum application
Leaching
D. Insufficient i) Low infiltration Leave crop residues and zero tillage
supply & retention Mulches
of water Cover crops
Leave stones on soil surface Trash lines
Vegetative cross-slope barriers Contour sowing, tillage and weeding Strip tillage
Minimum tillage
Deep till to loosen impermeable layers Furrows with raised beds or ridges Tied ridges
Stone lines Stone bunds Infiltration ditches Infiltration pits
Bench, orchard or platform terraces
ii) Strong winds Wind breaks
iii) High Leave crop residues and zero tillage
evaporation Mulches
iv) Low ability of Incorporation of organic manures
soil to retain water Incorporation of cover crops
Moisture-conserving fallows Sprinkler or drip irrigation
v) Low or erratic Drought resistant crops or varieties
rainfall Moisture-conserving fallows
Water harvesting
Strip cropping with runoff areas Cropping within half-moon bunds or pits
Water collection from roofs Irrigation systems
vi) Restricted Loosen dense layers with deep tillage
rooting Add amendments to neutralize
toxicities
Fertilize to correct nutrient deficiencies
Drainage ditches to lower water table
E. Insufficient i) Accumulation Diversion canals
supply of oxygen of runoff Safe discharge outlets
ii) High water table Raised beds and cambered beds
or impermeable Ridges
soil layers Subsoiling
Graded furrows Drainage ditches Safe discharge outlets
Problem Cause Possible Solution
F. Low biological i) Lack of residues Leave crop residues and zero tillage
activity and soil organic Mulches
matter Cover crops
Organic manures
Crops or varieties producing large quantities of slowly decomposing residues Higher plant populations
ii) “Tired” soils Crop rotations
Rotations with pastures
Organic manures and composts
iii) Toxic Natural pesticides
pesticides Insect-repellent crops
Insect traps
Integrated pest management Integrated weed management
G. Site instability i) Water erosion Leave crop residues and zero tillage
caused by runoff Leave stones on soil surface
Cover crops Mulches
Controlled grazing
Vegetative cross-slope barriers Stone barriers
Earth contour bunds Graded hillside ditches Roadside trenches Diversion canals Safe discharge outlets Bench terraces Orchard terraces
Individual platform terraces
ii) Wind erosion. Leave crop residues and zero tillage
Harvest crops well above ground level Mulches
Cover crops Intercropping
Sequential and relay cropping Higher plant populations Ridges and furrows Wind breaks
iii) Mass Tree crops
movements Diversion canals
iv) Flooding Diversion canals
Safe discharge outlets
4 Additional fertilizers may be required.
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Problem Causes Possible Solutions
H. Restricted root i) Excessive soil Subsoiling (for recuperation)
growth strength due to dense layers Vertical tillage with tined implements
Periodic deep tillage Controlled traffic
Biological “tillage” with tap-rooted crops
ii) Lack of oxygen See E
iii) Lack of Phosphate fertilizers
phosphorus Rock phosphates
Liming to reduce acidity
iv) Toxic See C
substances
I. Poor seed i) Lack of moisture Leave crop residues and zero tillage
germination Mulches
Deep placement of seeds in dry conditions
ii) Lack of oxygen Raised or cambered beds
Drainage ditches Diversion canals Safe discharge outlets Subsoiling
Land levelling
iii) Excessive Leave crop residues and zero tillage
temperatures Mulches
iv) Very low Ridge tillage
temperatures Raised beds
Wind breaks Drainage ditches Absence of residues
v) Cloddy structure Strip tillage
Disc tillage Organic manures
Rotations with grass fallows
J. Poor emergence i) Excessive soil Leave crop residues and zero tillage
strength due to Plant into cover crop residues
crusting Mulches
Organic manures Plant on ridges Higher sowing density Shallower depth of seeding ii) Excessive soil strength due
to dense
Vertical tillage with tined implements
topsoils Organic manures
Incorporate cover crops
Problem Cause Possible Solutions
K. High production costs i) High labour costs Manual seeders-fertilizers
Animal-traction seeders-fertilizers
ii) High machinery Manual no-tillage
costs Animal-traction tillage
iii) High pesticide Integrated weed management
costs Systemic herbicides
Crop rotations Cover crops
Integrated pest management Natural pesticides
Insect-repellent crops Insect traps
Bulk pesticide purchases
iv) High fertilizer Legume rotations
costs Organic manures
Composts
Economic applications of fertilizers Split applications
Fertilizer placement
Opportune timing of application Rock phosphates
Bulk purchases
v) High credit cost Formation of communal banks
L. Low profits i) Lack of diversifi- Crop and livestock diversification
cation Economic data for different enterprises
Marketing information Credit access
Improved availability of seeds and plants
Farm planning
ii) Low prices Bulk sales through farmer organizations
Silos to delay time of sale
Farm processing to increase value
M. Environmental i) Toxic pesticides Natural pesticides
pollution Integrated pest management
Insect-repellent crops Insect traps
Crop rotations
Integrated weed management Monitoring of soil and water quality
ii) Fertilizer Split fertilizer applications
contamination of Economic application rates
waters Fertilizer placement
Legumes to reduce N fertilizers Greater use of organic manures Greater use of compost Monitoring of water quality
iii) Sediment cont- See G i).
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