Soil Health Research and Development in PNG by Dr Ramakrishna Akkinapally

1. Soil Health Research and Development in PNG
Dr Ramakrishna Akkinapally
Deputy Director General
National Agricultural Research Institute (NARI)
Papua New Guinea (PNG)
Promoting Excellence in Agricultural Research for Development

2. • Population: 8.5 million
• Growth rate 2.7%
• Total land area: 465,000 km2
• Apart from New Guinea island, the
country has four large islands
(Manus, New Ireland, New Britain,
and Bougainville) and some 600
small islands lying between the
Coral Sea and the South Pacific
Ocean
• Climate : Tropical monsoon
• Rainfall: 2500-4000 mm
Geography and Socioeconomic Situation

3. Agriculture in PNG Development
• 23% GDP (of K13.5 billion) is
from agriculture
• 17% of GDP is from non-
export agriculture
• Less than 10% of non-export
commodities are marketed

4. Precursors to Soil Health Issues
• Rapid population growth leading to reduced rotation length leading to fertility decline
• Unsustainable logging: Erosion, fertility decline, reduced carbon stocks, loss of
biodiversity
• Mining: Immediate site impacts and risks of off-site contamination
• High rain fall and steep slopes leading to soil erosion
• Small-scale agriculture moving to steeper less suitable lands
• Accelerated soil erosion with plantations on marginal sloping lands
• Salinization and sodification
• Saltwater intrusion
• Loss of soil biodiversity
• Waterlogging
• Nutrient imbalance
• Nutrient mining

5. Unsustainable cultivation practices
• Shortening fallow
• Nutrients mining
• Poor Nutrients conservation
• Nutrients imbalance
• Traditional cultivation practices

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
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
#
Kandep
#
WABAG
#
Kompiam
#
Tambul
#
MOUNT HAGEN
#
KUNDIAWA
#
Gumine
#
Chuave
#
Lufa
#
Henganofi
#
Kainantu
#
GOROKA
N
EW
S
 Towns
Altitude
 1371 - 1473
 1474 - 1674
 1675 - 1962
 1963 - 2216
 2217 - 2614
6° 6°
5° 5°
143° 144° 145° 146°
Declining Soil Fertility

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 
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
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


#
Kandep
#
WABAG
#
Kompiam
#
Tambul
#
MOUNT HAGEN
#
KUNDIAWA
#
Gumine
#
Chuave
#
Lufa
#
Henganofi
#
Kainantu
#
GOROKA
N
EW
S
 Towns
Altitude
 1371 - 1473
 1474 - 1674
 1675 - 1962
 1963 - 2216
 2217 - 2614
6° 6°
5° 5°
143° 144° 145° 146°
Declining Soil Fertility
Acute K
deficiency
Enga
W. Highlands
E. Highlands

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 
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

#
Kandep
#
WABAG
#
Kompiam
#
Tambul
#
MOUNT HAGEN
#
KUNDIAWA
#
Gumine
#
Chuave
#
Lufa
#
Henganofi
#
Kainantu
#
GOROKA
N
EW
S
 Towns
Altitude
 1371 - 1473
 1474 - 1674
 1675 - 1962
 1963 - 2216
 2217 - 2614
6° 6°
5° 5°
143° 144° 145° 146°
Declining Soil Fertility
Acute K
deficiency
Acute S
deficiency
Enga
W. Highlands
Simbu
E. Highlands

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
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#
Kandep
#
WABAG
#
Kompiam
#
Tambul
#
MOUNT HAGEN
#
KUNDIAWA
#
Gumine
#
Chuave
#
Lufa
#
Henganofi
#
Kainantu
#
GOROKA
N
EW
S
 Towns
Altitude
 1371 - 1473
 1474 - 1674
 1675 - 1962
 1963 - 2216
 2217 - 2614
6° 6°
5° 5°
143° 144° 145° 146°
Declining Soil Fertility
Acute K
deficiency
Acute S
deficiency
Background
P deficiency
Background
P deficiency
Background
P deficiency
Enga
W. Highlands
Simbu
E. Highlands

10. Declining Soil Fertility
Some reasons for K and S deficiencies

11. Declining Soil Fertility
Some reasons for K and S deficiencies
Removal of K and S-rich
vines from cropping area

12. SO2
Declining Soil Fertility
Removal of K and S-rich
vines from cropping area
Burning of vegetation
releasing SO2 to atmosphere
Some reasons for K and S deficiencies

13. K+ SO4
2-
Declining Soil Fertility
Removal of K and S-rich
vines from cropping area
Leaching and outwash of K
and S from ash
Some reasons for K and S deficiencies

14. Declining Soil Fertility
Reason for background P deficiency

15. Declining Soil Fertility
Reason for background P deficiency
Fe-OH2
+
Al-OH2
+
Al-OH2
+
Soil
particle
H2PO4
-
H2PO4
-
H2PO4
-
Phosphorus fixation in acidic soil environment

16. Declining Soil Fertility & Health
Challenges
 Capacity
 Infrastructure (modern analytical and field gadgets)
 Funding
 Poor extension of new technologies
 Lack of Farmer awareness
 Policy support (on mining, logging, plantation on marginal soils etc)

17. Recent search Initiatives
• How do soil amendments—like cover crops,
biochar, manure, and improved crop fallows—
affect soil chemistry, soil biology, and crop
productivity?
• How do organic, conventional, and mixed crop
management systems affect soil health?
• How does the long-term use of a soil management
practice affect soil microbial diversity?
• How does soil microbial diversity, in turn, affect
greenhouse gas production and soil structure?
• How does the long-term use of a soil management
practice affect the amount of atmospheric carbon
sequestered in the soil?

18. • Legume Cover crops
• Improved fallows
• Application of compost or other organic
wastes
• Bio-fertilizer
• Balanced Fertilization
Priority Areas
Integrated Nutrient Management

19. Improved SALT system for sustainable crop production
1. Vetiver hedgerow

20. Work together with partners to combat food insecurity
and malnutrition
Thank You