# Presentation: 130140

## Achieving Food Security and  Mitigating Global Environmental Change: Is there a role for Crop Models in Decision Making?

- V. R. Reddy
- Crop Systems and Global Change Laboratory, Beltsville Agricultural Research Center, USDA-ARS, 10300 Baltimore Ave. Beltsville, MD 20705, USA
- V. Ambumozhi
- Institute for Global Environmental Strategies, Kansai Research Center, Kobe 651-00, Japan
- K. R. Reddy
- Dept. of Plant and Soil Sciences, Mississippi State University, Mississippi State, MS 39762, USA

## Outline 

- Past and future trends in population, food production and climate change perturbations
- Global environmental change and its impact on agriculture production systems
- Role of crop simulation models in addressing future food security and climate change

## Issues of 21st Century, Particularly in Developing Countries 

- Meeting food demands for the growing population
- Reducing the risks of soil and ecosystem degradation
- Minimizing the risks of eutrophication and contamination of natural waters
- Decreasing the net emissions CO2 and other greenhouse gases

## Trends That Shape Our Future

**Notes:**
India, China and Indonesia = 60% of production and 55% of area
US and Japan are small players with less 2% each

## Trends, Signs and Signatures from the EarthPast, Present and Future World Population

- Trends, Signs and Signatures from the EarthPast, Present and Future World Population

**Notes:**
The world population is on the rise; increasing exponentially.  We are at 6.4 billion mark today and the population is projected to reach 10 billion by 2050 and over 11 billion by 2100.  The present and projected future population exerts enormous pressure on natural and managed ecosystem goods and services.  We have to find ways to produce enough food and fiber and other services in a sustainable manner.  This is itself is an monumental task, challenge and an opportunity for everyone.     

## Trends, Signs and Signatures from the EarthPresent and Future World Population Trends

- 56%      10%    50%        120%

- -5%     42%       39%

- Trends, Signs and Signatures from the EarthPresent and Future World Population Trends

## Trends, Signs and Signatures from the Earth Global Major Foods – Per Capita Consumption

## Trends, Signs and Signatures from the EarthMaize - Production and Yield – Selected Counties

- Trends, Signs and Signatures from the EarthMaize - Production and Yield – Selected Counties

**Notes:**
USA, China and Brazil = 67% of production and 46% of the area
India = 2%

## Trends, Signs and Signatures from the EarthRice - Production and Yield – Selected Counties  

- Trends, Signs and Signatures from the EarthRice - Production and Yield – Selected Counties

- P= 60%, and A= 55%

## Trends, Signs and Signatures from the EarthRice - Production and Yield – Selected Counties

- Trends, Signs and Signatures from the EarthRice - Production and Yield – Selected Counties

## Trends, Signs and Signatures from the Earth Cropland area, Irrigation and Salinization

- 		----------------------------- Mha --------------------------------
- China		124.0		54.4 (22%)	7-8 (14%)
- India		161.8		54.8 (31%)	10-30 (50%)
- USA		177.0		22.4 (13%)	4.5 -6 (15%)
- USSR		204.1		19.9 (2%)	2.5-4.5 (21%)
- World		1364.2		271.7 (21%)	62-82 (37%)

- Percent change since 1985

- Year 2000

- Trends, Signs and Signatures from the Earth Cropland area, Irrigation and Salinization

- S.G. Pritchard and J. S. Amthor, 2005

## Trends, Signs and Signatures from the EarthPopulation, cereal yield, arable and irrigated area, N use  

**Notes:**
We have to consider the past and present trends and pressures that are associated with food and fiber production before we consider the climate change; links between crop yield and production and population dynamics, arable area, irrigation and salinization, fertilizer use etc.,

## Feeding 10 Billion Mouths

- We must develop the capacity to feed 10 billion people within in the next 40 to 50 years
- The average world current cereal yield is about 3 tons per ha for about 6 billion people
- We need about 4 tons per ha for 8 billion (33 % more than the current), and 5 tons per ha for 10 billion (67 % more than the current)

## Increase in the area of land under cultivation

Displacement of lower yielding crops by higher yielding ones (done since the dawn of domestication)

Efficiency of crop production in terms of:
		Per unit of land area (yield per ha)
		Per unit of time
		Per unit of inputs such as fertilizers, water and     labor etc.

- Displacement of lower yielding crops by higher yielding ones (done since the dawn of domestication)
- Efficiency of crop production in terms of:
- 		Per unit of land area (yield per ha)
- 		Per unit of time
- 		Per unit of inputs such as fertilizers, water and     labor etc.

- Routes to Greater Food Production

## Here comes the greatest challenge of our time, The Global Climate Change

- Here comes the greatest challenge of our time, The Global Climate Change

## Trends, Signs and Signatures from the Earth

- Greenhouse gases (CO2, CH4, N2O etc.)
- Temperatures
- Glaciers, oceans and sea-levels
- Precipitation patterns and drought intensities
- Extreme events
- Higher ozone and UV-B radiation

## Trends, Signs and Signatures from the EarthGlobal Carbon Emissions- Sources

## Trends, Signs and Signatures from the EarthGlobal Carbon Emissions and Carbon Fixation

- Trends, Signs and Signatures from the EarthGlobal Carbon Emissions and Carbon Fixation

## Trends, Signs and Signatures from the EarthAtmospheric Carbon Dioxide Concentration

- Trends, Signs and Signatures from the EarthAtmospheric Carbon Dioxide Concentration

## Trends, Signs and Signatures from the EarthProjected Global Carbon Dioxide Concentrations

## Global Warming and the Ozone Story 

- CFCs are commonly used as refrigerants, solvents, and foam blowing agents. The most common CFCs are CFC-11, CFC-12, CFC-113, CFC-114, and CFC-115.** **

- Global Warming and the Ozone Story

- Global Warming Process

- Ozone Depleting Process

## Trends, Signs and Signatures from the EarthPast and current levels in global greenhouse gas concentrations, rates of change and atmospheric lifetime 

| Period | CO2 | Methane | Nitrous oxide | Chloroflu-rocarbon-11 | Hydrofluro-carbon-23 | Perfluro-methane |
| --- | --- | --- | --- | --- | --- | --- |
| Pre-industrial concentration (1850) | about 
280 ppm | about 
700
 ppb | about 270 ppb | zero | zero | 40
ppt |
| Concentration in 1998 | 365
ppm | 1745
ppb | 314
ppb | 268
ppt | 14
ppt | 80
ppt |
| Rate of change | 1.5
ppm/yr | 7.0 ppb/yr | 0.8
ppb/yr | -1.4
ppt/yr | 0.55 
ppt/yr | 1 
ppt/yr |
| Atmospheric lifetime | 5 to 200 years | 12 
years | 114
years | 45
years | 260
Years | >50,000 years |

- Trends, Signs and Signatures from the EarthPast and current levels in global greenhouse gas concentrations, rates of change and atmospheric lifetime

## Trends, Signs and Signatures from the EarthFuture trends in global carbon dioxide concentration and associated climate change, if no interventions are made

| 
Climate variable  | 
2025 | 
2050 | 
2100 |
| --- | --- | --- | --- |
| Carbon dioxide concentration | 405-460 ppm | 445-640 ppm | 540-970 
ppm |
| Global mean temperature change from the year 1990 | 0.4-1.1
oC | 0.8-2.6
oC | 1.4-5.8
 oC |
| Global mean sea-level rise from the year 1990 | 3-14
cm | 5-32
cm | 9-88
cm |

## Climate Change and Crop ProductivityCotton Photosynthesis – Solar Radiation

## Climate Change and Crop ProductivityPhotosynthesis – Leaf Water Potential

- Well-watered                                                   Water stressed

## Climate Change and Crop ProductivityCotton Photosynthesis – UV-B Radiation

## Climate Change and Crop ProductivityTemperature and CO2 – Rice Growth

- Baker and Allen, 1993

## Climate Change and Crop ProductivityTemperature and CO2 – Rice Yield

- Baker and Allen, 1993

## Climate Change and Crop ProductivityRice Growing Areas 

- Climate Change and Crop ProductivityRice Growing Areas

## Ambient temperature: 25.36°C = 8.26 t/ha

- Ambient plus 5°C: 30.36°C = 5.51 t//ha, 33%

## Climate Change and Crop ProductivityTemperature and Cotton Growth

- Climate Change and Crop ProductivityTemperature and Cotton Growth

## Climate Change and Crop ProductivityTemperature and CO2 – Cotton Reproductive Growth

- Fruit Production Efficiency

## High Temperature Effects on CottonHeat-blasted flower buds and flowersSan Joaquin Valley, California

## Climate Change and Crop ProductivityTemperature Effects on Crop Yield – Several Major Crops

| Crop | Topt, °C | Tmax, °C | Yield 
at Topt, t/ha | Yield 
at 28 °C, t/ha | Yield at 32°C
t/ha | % decrease (28 to 32 °C) |
| --- | --- | --- | --- | --- | --- | --- |
| Rice | 25 | 36 | 7.55 | 6.31 | 2.93 | 54 |
| Soybean | 28 | 39 | 3.41 | 3.41 | 3.06 | 10 |
| Dry bean | 22 | 32 | 2.87 | 1.39 | 0.00 | 100 |
| Peanut | 25 | 40 | 3.38 | 3.22 | 2.58 | 20 |
| Grain sorghum | 26 | 35 | 12.24 | 11.75 | 6.95 | 41 |

## Climate Change and Crop ProductivityTemperature and CO2 – Rangeland C4 Grass – Big Bluestem

- Vegetative Weight and Seed Weight

## Slide 36

## Climate Change and Crop ProductivityPresent and Projected Temperature Changes

## Climate Change and Crop ProductivityConclusions – Temperature and CO2 Interactions

- There are no beneficial effects of elevated CO2 on reproductive processes in the crops investigated (cotton, bean, rice, sorghum and soybean).
- There are no beneficial interaction of temperature or UV-B on CO2 effects on reproductive processes.
- Higher temperatures and higher UV-B aggravated the damage on many reproductive processes.

- Climate Change and Crop ProductivityConclusions – Temperature and CO2 Interactions

## Why Do We Need Models?

- Help pinpoint knowledge gaps
- Design critical experiments
- Synthesize knowledge about different componentsof a system
- Summarize data
- Transfer research results to users

## Crop Model Applications for Natural

- Resource management (e.g. several Govt. agencies and private comp. use)
- Climate change and policy analysis
- Production forecasts (e.g. global, regional and local forecasts)
- Research and development (e.g. research priorities and guide fund allocations)
- Turning information into knowledge (e.g. information overflow in every area including agricultural research)

-  Resource Management

## Model Mechanics

- GOSSYM: Model Structure

-  Models needs to be robust as simple models can’t predict complex process.
-  Like any other system, models needs to be continuously updated as new information becomes available.
-  Models needs to be extensively tested across diverse environments, soil conditions and cultural practices.
-  Information feedback from scientists, farmers and farm managers needs to be taken for user-friendliness.

- Mechanistic, process-level cotton simulation model - GOSSYM

## Crop Model Applications for climate Change Scenarios – Case Study  

- Reddy et al., 2002

## Crop Model Applications for climate Change Scenarios – Regional Emphasis  

- Crop Model Applications for climate Change Scenarios – Regional Emphasis

- Doherty et al. 2003)

## Climate Change and Crop ProductivitySome Considerations

- We should consider other stresses on food production systems such as population dynamics, habitat destruction and fragmentation, land-use changes, biodiversity and invasive species dominance.
- The current and projected changes in climate are unprecedented, and the ecosystems including managed ecosystems such as agriculture may not cope with the changes projected in climate.

- Climate Change and Crop ProductivitySome Considerations

## Climate Change and Crop ProductivitySome Considerations

- For a shorter-term, we must develop crop varieties which can withstand changes projected in climate to meet the growing demands for food.
- We must also develop models that provide adequate warning or guidance for policy makers to act proactively rather than reactively.
- Everybody and every nation should participate in the process, opportunities are there for everyone.

- Climate Change and Crop ProductivitySome Considerations

## We will be over 10 billion by 2050 in a much different climate than what we have today

- We need to produce enough goods and services in a sustainable way

- Thanks and any Questions?

## Leading America towards a better future 

*Leading America towards a better future *
*through agricultural research and information*

**Notes:**
Thank you for your attention.