soil health and environmental management for sustainable agricultural production systems
TRANSCRIPT
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Carbon Management and Sequestration Center
Soil Health and Environmental Management for Sustainable Agricultural Production Systems
Rattan LalCarbon Management and Sequestration Center
The Ohio State UniversityColumbus, Ohio
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Carbon Management and Sequestration Center
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18,000 BC6,000 BC 14,000 BC10,000 BC2,000 BCAD 2,000-42-40
-36-34
Warm & Wet
Cold & Dry
δ18
(0%
)
8,000 BCBeginning of Agriculture
1750Industrial
Revolution
EARTH’S HISTORIC TEMPERATUREAND THE EVOLUTION OF AGRICULTURE
(Fagan, 2004)
Time
THE LONG SUMMERAnthropocene
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THE ANTHROPOGENIC DRIVER
I = P x A x T
P = Population A = Affluence T = Technology
Over the last10,000 years, the number of humans has increased about a thousand-fold from 2- 20 million to7.3 billion.
1.01800
1.31850
1.71900 1.8
1910 1.91920
2.11930
2.31940
2.51950
3.01960
3.71970
4.419805.3
1990
6.12000
7.02011
7.52020
8.12030
8.62040
9.72050
11.22100
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Carbon Management and Sequestration Center
People living in water-stressed river basins:
2000 = 2.3 bn 2025 = 3.5 bn
Scarce Water Resources: Ogalalla, IGP, NCP, etc.
HUMAN-ECOSYSTEM INTERACTIONS
Population2015 – 7.3B2050 – 9.7B2100 – 11.2B
Soil ErosionWater = 1.1Bha
Wind = 0.55Bha
Secondary Salinization
20% of all irrigated lands
Algal BloomsRegions: Great Lakes, Gulf of
Mexico, Chesapeake Bay, Lake Taihu in China, Baltic Sea
etc.
Loss of Agric. Land to Sealing and UrbanizationBy 2030, global urban land cover
will increase by 152 Mha or 10% of current arable land area
Loss of Biodiversity1000 to 10,000 sp./yr,
background rate of 5 sp./yr
Tropical Deforestation1990s = 8 Mha/yr
2000s = 7.6 Mha/yrA region equivalent to Sri Lanka
Loss of Terrestrial C Pool
Land Use = 486 Pg Soil = 78 Pg
www.nrcs.usda.govwww.soils4teachers.orgLal (2015)thewatchers.adorraeli.comwww.emaze.comwww.sustainableworks.org
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THE RESOURCES USED FOR AGRICULTURE
• 38% of the Earth’s terrestrial surface is used for agriculture,• 75% of agricultural land (3.73 Bha) is allocated to raising animals,• 70% of the global freshwater withdrawals are used for irrigation,• 30-35% of global greenhouse gas emissions are contributed by
agriculture,
And yet 1 in 7 persons is food-insecureand 2-3 in 7 are malnourished.
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MEETING FOOD DEMAND BY 2050The world produces enough food to feed 10 billion people . Thus, food and nutritional security must be achieved by:• Reducing waste (30-50%),
• Increasing access to food by addressing poverty, inequality, wars and political instability,
• Improving distribution,
• Increasing use of pulses and plant-based diet,
• Accepting personal responsibility of not taking things for granted, and
• Increasing agronomic productivity from existing land, restoring degraded lands, enhancing BNF by legumes and converting some agricultural land for nature conservancy without any conversion of natural land to agro-ecosystems,through sustainable intensification
sustainable intensification
No additional appropriation of land and
water to agriculture
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Resilience of Soil-Ecological Systems
It has multiple regimes (stable states) which are separated by thresholds
Thresholds
Critical Threshold
The current state of the system
Possible states in which the system can still have the same function Irreversible
Degradation
Resilience
Regime Shift
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• Extractive Farming/Subsistence
• Depletion of SOC and Nutrients• Decline in Soil Structure
• Loss of Soil Resilience
• Decline in Ecosystem Functions and Services
• Loss of Soil biodiversity• Disruption of Key Processes
• Hunger• Malnutrition• Political Unrest• Civil Strife• War and insecurity• The Migrant Crisis
Severe Degradation
THE REGIME SHIFT BY EXTRACTIVE
FARMING
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• Replace what is removed,
• Respond wisely to what is changed, and
• Predict what will happen from anthropogenic and natural perturbations
SUSTAINABLE SOIL MANAGEMENT
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The strategy is to produce more crops:
• from less land,• per drop of water,• per unit input of fertilizers
and pesticides,• per unit of energy, and• per unit of C emission.
Produce morefrom less
SUSTAINABLE INTENSIFICATION
Pulses in rotation can produce more
from less
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MOST IMPORTANT THINGS CANNOT BE MEASURED BUT MUST BE MANAGED
(Edward Demmings)Therefore, question is not "What is there in the soil that can be measured, but what it
does which must be quantified "?
&
What it does is "soil quality".
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SOIL QUALITY
Soil quality is a journey and not a destination,
Because a destination keeps changing with demands of each generation.
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“The first step in the science of agriculture is the recognition of soils and of how to distinguish that which is of good quality and that which is of inferior quality. He who does not possess this knowledge lacks the first principles and deserves to be regarded as ignorant”.
(Vol. 1, p. 23)
“One must also take into consideration the depth of the soil, for it often happens that its surface layer may be black.”
(Vol. 1, p. 336)
a Moorish Philosopher wrote in the “Book on Agriculture” during the 12th century:
Ibn-Al-Awan,
KITAB-AL-FELAHA
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PULSES & SDGS
• Soil restoration • Human Nutrition• Climate Mitigation
Chemical• Recycling nutrients• Soil pH
• CEC• Elemental balance
Biological• BNF• MBC• SOC
• Disease-suppressive soils
• Soil enzymes• Biodiversity
(earthworms)
PhysicalImproving:
• Aggregation (glomalin)• Porosity • Tilth (biopores)• Aeration Soil
Health
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BNF BY PULSE CROPS
• 50-80% of N uptake in legumes comes from BNF.
Pulse Crop BNF (kg/ha)
Schoenau (2016)
Lentil 30-120Chickpea 20-100Dry Bean 5-70Faba Bean 80-160
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Carbon Management and Sequestration Center
BNF BY CROP LEGUMES
• BNF by crop legumes is estimated at 20-22 Tg N/yr
• Residue of pulses (chickpea, lentil) has a lower C:N ratio (17) compared with 41 for oilseed and 32 for wheat.
• Thus, pulse in the rotation can impact soil health
1 kg of N fertilizer = 1.25 kg C
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WUE OF SORGHUM FOLLOWING DIFFERENT CROPS IN QUEENSLAND, AUSTRALIA
Θ at planting sorghum was the lowest in plots previously sown to siratro and lucerne, and the highest in sorghum and mungbean.
Treatment N Fertilizer
WUE (kg grain/ha ×mm)
1995 1996 1997Sorghum 7.0 6.0 4.7
Mungbean 11.2 14.0 10.6
Siratro 10.3 11.8 12.1
Lucerne 9.0 10.5 7.2
Lablab 11.6 12.5 11.2
Desmanthus 11.0 10.3 5.8
LSD (.05) NS 3.7 3.3
Armstrong et al. (1999)
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“Soil biota is the bioengine of the Earth”
There is no such thing as a free biofuel from crop residues.
ECONOMICS OF RESIDUE REMOVAL FOR BIOFUEL
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NO-TILL FARMING AS ANEMERGING GLOBAL TECHNOLOGY
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PIGEON PEA F. SINGH AND D.L. OSWALT (1992) ICRISAT
A stylized pigeonpea plant.
Pigeon pea roots may extend >2m deep, with extensive
development in 60 cm
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http://soilquality.org/indicators/soil_structure.html
SOIL STRUCTURE, ROOTS & GLOMALIN
IT’S NOT DIRT
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Corn withno residues
Corn with 100% residues
Coschocton, 2012
Residues plowed under No-till with mulch
IMPORTANCE OF SOM & CROP RESIDUES TOSOIL QUALITY & HEALTH
All photos: R. Lal, Coschocton, OH 2012
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Tillage
SOC Pool (Mg/ha, 0-20 cm) C Sequestration
(kg/ha/yr)Initial Final
No-till 32.7 A 37.3 A 657Conventional 29.2 B 33.9 B 671Average 30.9 35.6
Duration = 7 yrs comparison within column
TILLAGE EFFECTS ON SOC POOL IN SETAT, MOROCCO
(BESSAM AND MRABET, 2003)
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N, P, K, Zn, H2O
Delivering nutrients and water directly to plant’s roots
TOWARDS C-NEUTRAL AGRICULTURE
Chatting with plants
through molecular-
based signalsNo-till Farming
INM
Soil biota and ecosystems services
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GLOBAL POTENTIAL OF SOC SEQUESTRATION(Pg C/YR)
Cropland: 0.4-1.2
Grazing land: 0.3-0.5
Salt-affected soils: 0.3-0.7
Desertified soils: 0.2-0.7
Total: 1.2-3.1
Lal (2010)
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Carbon Management and Sequestration Center
GLOBAL SOIL ORGANIC CARBON POOL 0-40cm DEPTH
Total Pool = 850 Gt .... Batjes
(1996)
0.4% Increase/yr = 3.6 Gt C/yr
OFF-SETTING OIL BY SOIL C SEQUESTRATION
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SOCIETAL VALUE OF SOC
• Cost of Residue + Nutrients: $120/ MgC• Cost of Nutrients Only : $102/ MgC
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• Animal Power• Rotations
• Sustainableintensification (SI)
• Rhizosphericprocesses
• Disease-suppressivesoils
• Soil-less agriculture
• The nexus approach
• Phytobiome management
• Recarbon-ization of the biosphere
• Nutrition-sensitive agriculture
• SI Restorative Agriculture
• Soil-less agriculture
• Phytobiome management
• Urban
agriculture
• Space farming
TECHNOLOGICAL INNOVATIONS
• Hand Tools GR
EEN
REV
OLU
TIO
N
Mac
hine
pow
er
Fe
rtiliz
ers
G
erm
plas
m
YEAR
REL
ATIV
E FO
OD
PR
OD
UC
TIO
N (M
g/ha
)
WORLD POPULATION (BILLIONS)
12
8
6
4
1
0.8
1520
1750 1850 1950 1975 2000 2025 20502015
0.8 1 3 4 6 8 9.67.6
C
onse
rvat
ion
agric
ultu
re
Mic
ro-ir
rigat
ion
Pre
cisi
on fa
rmin
g
Per
enni
al c
ultu
re
Com
plex
rota
tions
G
MO
s
Improved cultivars
Biotech-nology
No-till farming
INM
IPM
Carbon sequestration
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Carbon Management and Sequestration Center
2015 - 2024
• Sustainable Intensification• Phytobiome Management• Disease-Suppressive Soils• Urban Farming• Space Agriculture• Recarbonization of the Soil &
Biosphere• The Nexus Approach
The IUSS-Decade of Soil
IUSS
SOIL IN THE 21ST CENTURY
2025 - 2050
• Nutrition-Sensitive Agriculture• Pharmaceutical Products• Synthetic Soils• Soils of Extraterrestrial Bodies• Soil Processes & Hypogravity• Pedological Transformations &
Climate ChangeClimate-Resilient Agriculture
IUSS
SOIL IN THE 21ST CENTURY
Extraterrestrial Soils & Agriculture?Hypogravity Pedology?
Sky Farming?Climate & Soil?
Pharmaceuticals?
21ST CENTURY ROAD MAP OF SOIL SCIENCESUSTAINABLE DEVELOPMENT
GOALS