MANAGING SOILS TO ADVANCE WORLD AGRICULTURE Presentation at the GCHERA-WAP,NAU, Nanjing, China 28 October 2018

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1 MANAGING SOILS TO ADVANCE WORLD AGRICULTURE Presentation at the GCHERA-WAP,NAU, Nanjing, China 28 October 2018 Dr. Rattan Lal The Ohio State University Columbus, OH 1

2 SOIL AND LIFE Essentially all life depends upon the soil---there can be no life without soil and no soil without life;they have evolved together (Charles E.Kellogg,USDA) The weight of live organisms in arable land is 5 Mg/ha in temperate environment. 2

3 Soil Erosion on an Alfisol in Western Nigeria in 1970 (Lal 2004) 3

4 Newly Established Run-Off Plots at IITA in March

5 Excessive Run-Off and Soil Erosion in Newly-Plowed Bare Soil Surface with Strong Loss of Soil Organic Matter (1972) 5

6 Mulch Effects on Nutrient Losses In Soil Sediments For 5% Slope Gradient (1974) Mulch Rate (Mg/ha) Nutrient Loss (kg/ha) N P K Ca Mg Total T T T T T T No-Till T T T T T T T= < 0.1 kg/ha (Lal, 1976c) 6

7 Relationship Between Slope Steepness and Soil Erosion for Different Mulch Rates Mulch rate Regression Correlative Mean soil loss (Mg/ha) Equation Coefficient (Mg/ha) 0 Y= 11.8 S Y= 0.5 S Y= S Y= S Y= Erosion (Mg/ha) S= Slope (%) (Lal, 1976b) 7

8 NO-TILL FARMING AS AN EMERGING GLOBAL TECHNOLOGY (Lal,1971) 8

9 Mucuna utilis (velvet bean) as a Cover Crop (Lal 2004) 9

10 Costs of Earthworms Under a Forest Cover in the Humid Tropics 10

11 Accumulative Runoff (mm) Effects of Tillage Systems on Water Runoff Plowed No-Till Time (minutes) 11 (Lal. 1979b)

12 The Maximum Soil Temperature ( ) at 5cm Depth at 37 Days After Seeding Surface Cover Flat Ridges Bare Corn Cowpeas Mulching (Lal,1975;1982;Ghuman and Lal, 1983) 12

13 Deforestation by Tree Pusher and Root Rake (Lal 2004) 13

14 Land Clearing by Front-Mounted Shear Blade 1977 (Lal 1981b) 14

15 A Stump of Palm Tree Sheered at the Ground Level by a Front-Mounted Sheer Blade 15

16 Traditional Slash and Burn Method of Land Clearance; Mulch-Capped Yam Mounds in the Background 16

17 Installation of H-Flume and Retaining Walls for Establishing a Watershed at IITA in

18 H-Flume with a Water Stage Recorder and a Coshocton Wheel Sampler 18

19 An Undisturbed Monolith Lysimeter Being Installed at a Watershed Experiment in 1978 at IITA 19

20 Excessive Run-Off and Erosion Observed on Land Cleared with a Tree- Pusher Root Rake Device (April 1978) 20

21 Deforestation and Tillage Effects on Runoff and Erosion in Nigeria Under Maize Land management treatment Runoff (mm) Soil erosion (Mg/ha) Forest <1 <0.01 Traditional farming Manual clearing/no-till Manual clearing/ conventional tillage Shear blade clearing/ no-till Tree pusher-toot rake/ no-till Tree pusher-root rake/ conventional tillage (Lal, 1996) 21

22 Contour Hedgerows of Leucocephala for Sloping Land (Lal 2004) 22

23 Grain Yield (Mg/ha.yr) Effects of Mechanized Tillage Operations on Maize Grain Yield After 12 Consecutive Crops of Maize 5 3 No Till Conventional Year 23 (Couper, Lal and Classen, 1979;Lal,1991)

24 ECONOMICS OF RESIDUE REMOVAL FOR BIOFUEL Soil biota is the bioengine of the Earth There is no such thing as a free biofuel from crop residues. Lal (2017) 24

25 PIGEON PEA F. SINGH AND D.L. OSWALT (1992) ICRISAT Pigeon pea roots may extend >2m deep, with extensive development in 60 cm A stylized pigeonpea plant. Lal (2017) 25

26 Watershed Management Experiment with No-Till Corn at IITA in 1979 (Dr. Lal with Dr. Hartman) 26

27 A Training Class on Soil and Water Conservation at IITA in

28 A Training Class for Demonstration of a Triangular Weir at IITA Revelle visit 28

29 AND THE ECOSYSTEM SERVICES GENERATED COUPLED CYCLING OF H 2 O, C, N, P Sustainable use of soil & water resources Lal (2010) 29

30 SOIL EROSION AS A CARBON SOURCE World 1.1 Pg C/y USA 15 Tg C/y Brazil 60 Tg C/y India Tg C/y Iceland Tg C/y Lal(2003) 30

31 SOIL C PROFILE AND TILLAGE METHODS SOC Sequestration PLOW TILL NO-TILL

32 IMPORTANCE OF SOM & CROP RESIDUES TO Corn with no residues SOIL QUALITY & HEALTH Corn with 100% residues Coshocton, 2012 Residues plowed under R. Lal, Coshocton, OH 2012,NC1178 Project No-till with mulch 32

33 CARBON-BASED FERTILIZATION CNPK with ISNM rather than NPK with Chemical Fertilizers 33

34 CROP YIELD INCREASE WITH INCREASE IN SOC BY 1 MgC/ha Crop Yield Increase (Kg/Ha MgC) Maize Soybeans Wheat Rice Sorghum Millet Beans million tons/yr in developing countries Lal (2005) 34

35 TECHNICAL POTENTIAL OF C SEQUESTRATION I. Soils Pg C/yr (2.45 Pg C/yr) Lal (2018) II. Terrestrial Biosphere by 2100 Soils Pg Vegetation 155 Pg Total 333 Pg (157 ppm CO 2 ) Lal et al. (2018) 35

36 SOCIETAL VALUE OF SOC Cost of Residue + Nutrients: $120/ MgC Cost of Nutrients Only : $102/ MgC 36

37 MEETING FOOD DEMAND BY 2050 The 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, and alternate source of protein, 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 agroecosystems, through sustainable eco-intensification and restoration of soil health. 37

38 SUSTAINABLE INTENSIFICATION The strategy is to produce more food: from less land, Produce more from less per drop of water, per unit input of fertilizers and pesticides, per unit of energy, and per unit of C emission. 38

39 MANAGING SOIL HEALTH AND SOM Integrated livestocktree systems Molecular-based signals Mulch No-till Cover crop High Soil Biodiversity N, P, K, Zn, H 2 O Rhizobium Mycorrhizae Disease- Suppressive soil Integrated Nutrient Management 39

40 1. Causes of Soil Degradation The biophysical process of soil degradation is driven by economic, social and political forces. Vulnerability to degradation depends on how rather than what is grown. 40

41 2. Soil Stewardship & Human Suffering When people are poverty stricken, desperate and starving, they pass on their sufferings to the land. Love and business and family and religion and art and patriotism are nothing but shadows of words when a man s starving. (O. Henry) 41

42 3. Nutrient, Carbon & Water Bank It is not possible to take more out of a soil than what is put in it without degrading its quality. Only by replacing what is taken can a soil be kept fertile, productive, and responsive to management 42

43 4. Marginality Principle Marginal soils cultivated with marginal inputs produce marginal yields and support marginal living. 43

44 5. Organic vs. Inorganic Nutrients Plants cannot differentiate the nutrients supplied through inorganic fertilizers or organic amendments. The strategy is of producing more from less. 44

45 6. Soil Carbon & GHG Effect Mining C has the same effect on global warming whether it is through mineralization of soil organic matter and extractive farming or burning fossil fuels or draining peat soils. Soil can be a source or sink of GHGs depending on land use and management 45

46 7. Soil vs. Germplasm The potential of elite varieties can be realized only if grown under optimal soil conditions because even they cannot extract water and nutrients from any soil where they do not exist. Yet, reducing pesticide input by using diverse species/varieties may be a good tradeoff 46

47 8. Soil as Sink for Atmospheric CO 2 Soils must be integral to any strategy of mitigating global warming and improving the environment. 47

48 9. Engine of Economic Development Sustainable management of soils is the engine of economic development, political stability and transformation of rural communities,especially in developing countries. 48

49 10. Traditional Knowledge & Modern Innovations Sustainable management of soil implies the use of modern innovations built upon the traditional knowledge. 49

50 SOILS AND ECOSYSTEM SERVICES 2 - Food Security 50

51 SOIL HEALTH FOR CLIMATE AND FOOD When asked what would I suggest to mitigate global warming, purify air and water and end global hunger and malnutrition, the logical response would be to change the ways soils are taken for granted and abused to produce, transport, process, and consume food ; and misused to procure feed, fiber, fuel, bricks and other ecosystem services. A prudent strategy would imply making soil, water and agriculture an integral part of the solution, and empowering farmers and land managers to produce more and more from less and less by reducing waste,enhancing the eco-efficiency restoring degraded soils, afforesting the denuded lands, and saving soil and water for nature conservancy. Rattan Lal 28October,2018 GCHERA-WAP 51