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Adapted from S. Brouder & H. Gómez-Macpherson (2014). The impact of conservation agriculture on smallholder agricultural yields: A scoping review of the evidence. Agriculture, Ecosystems and Environment, 187, 11-32 http://www.sciencedirect.com/science/journal/01678809/187
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Adapted from
S. Brouder & H. Gómez-Macpherson (2014). The impact of conservation agriculture on smallholder agricultural yields:
A scoping review of the evidence. Agriculture, Ecosystems and Environment, 187, 11-32
http://www.sciencedirect.com/science/journal/01678809/187
FAO Conservation Agriculture 3 pillars
1. minimum disturbance of soil (ideally zero-tillage)
2. retention of sufficient crop residue to provide surface coverage (at least 30% ground cover)
3. diversified cropping patterns(rotation)
Conservation Agriculture
most farmers adopt 1 or 2 of these pillars
highly variable results regarding effects on soil quality and productivity: positive / negative / neutral
short term / long term
poor/confusing reporting: what is conventional tillage? minimum tillage? reduced tillage? How are residues manage?
complex interaction of system management, system productivity components and prevailing conditions
Conservation Agriculture
1st adopting zero-tillage (no soil disturbance)
The complexity in 3 steps
then + maintaining residues on the ground (mulch)
then + rotate crops
Soil compaction Weeds
competitionFertilizer / lime
placement
Water availability
Advanced sowing
Pests & diseases
Soil water
infiltration
Nutrient availability
Soil surface structure=crust
Crop establishment
Waterlogging(Percolation Leaching) Runoff Erosion
Root growth
Extra crop
ZERO TILLAGE (NO SOIL DISTURBANCE)
negative effect
Machinery adapted
Minimum, sporadic, controlled traffic
positive effectlong-term
Brouder & Gómez-Macpherson (2014)
Adapting machinery / operations
controlled trafficlocalized subsoiling for decompaction
Aggregates SOM
Soil compaction Weeds
competitionFertilizer / lime
placement
Water availability
Advanced sowing
Pests & diseases
Soil water
infiltration
Nutrient availability
Crop establishment
WaterloggingPercolation Leaching Runoff Erosion
Root growth
Extra crop
ZERO TILLAGE(NO SOIL DISTURBANCE)
long-term
negative effectpositive effect
+ RESIDUESSoil water
evaporation
Flood/furrow irrig. application
Seedingthroughresidues
↓ Soil To (spring crops)
Immobilization
Livestock, removed
MachineryCultivar, inputs
Soil surface structure=crust
Brouder & Gómez-Macpherson (2014)
Adapting machinery / operations
JJ.Pérez
Adapting local seeders
Aggregates SOM
Soil compaction Weeds
competitionFertilizer / lime
placement
Water availability
Advanced sowing
Pests & diseases
Soil water
infiltration
Nutrient availability
Soil surface structure
Crop establishment
WaterloggingPercolation Leaching Runoff Erosion
Root growth
Extra crop
long-term
negative effectpositive effect
+ RESIDUESSoil water
evaporation
Flood/furrow irrig. application
Seedingthroughresidues
↓ Soil To (spring crops)
Immobilization
+ ROTATIONSeedMarket
+ COVER CROPS
ZERO TILLAGE(NO SOIL DISTURBANCE)
Brouder & Gómez-Macpherson (2014)
Cover crops: brachiaria
JJ.Pérez
Aggregates SOM
Soil compaction Weeds
competitionFertilizer / lime
placement
Water availability
Advanced sowing
Pests & diseases
Soil water
infiltration
Nutrient availability
Soil surface structure
Crop establishment
WaterloggingPercolation Leaching Runoff Erosion
Root growth
Extra crop
long-term
negative effectpositive effect
+ RESIDUESSoil water
evaporation
Flood/furrow irrig. application
Seedingthroughresidues
↓ Soil To (spring crops)
Immobilization
+ ROTATION
+ COVER CROPS
f (soil type, To, rain)
ZERO TILLAGE(NO SOIL DISTURBANCE)
Brouder & Gómez-Macpherson (2014)
