Agriculture Sustainability and Plant Physiology

Lecture Outline

• Challenges we face in agriculture• Sustainability defined• Issues related to food production

– Current situation of production and consumption– Public knowledge of agriculture

• Sustainability benefits• Challenges in food production sustainability• Linking knowledge of plant physiology in

sustainability discussions

Food Food SecuritySecurity

PovertyPoverty

Food Production

Land Resources

EcosystemsNutritionHealth

Food Systems

Population

Climate

Energy

Int. Trade

Water

Emerging Challenges

Existing Challenges

Agriculture Challenges

Ecological Perspective:

• Sustainable Agriculture demands a holistic perspective:

• Don’t treat the symptoms, manage the cause!

Soil Farmers

Water

Crops

Wildlife

Livestock

Sustainable Agriculture

• Three components– Economic– Social– Environmental

• ATTRA. 2003. Applying the principles of sustainable farming. Accessed at www.attra.ncat.org

Indicators of Economic Sustainability

• Family savings or net worth is consistently going up

• Family debt is consistently going down• Farm enterprises are consistently

profitable from year to year• The purchase of off-farm feed and

fertilizer is decreasing• Reliance on government payments is

decreasing

Indicators of Social Sustainability

• The farm supports other businesses and families in the community

• Dollars circulate within the local economy• The number of rural families is going up

or holding steady• Young people take over their parents‘

farms and continue farming• College graduates return to the

community after graduation

Indicators of Environmental Sustainability

• The ground is not left bare

• Clean water flows in the farm's ditches and streams

• Wildlife is abundant

• Fish are prolific in streams that flow through the farm

• The farm landscape is diverse in vegetation

http://upload.wikimedia.org/wikipedia/commons/1/15/Nested_sustainability-v2.gif

Patterns of Recent Agriculture Production in US

• Consolidation of farms• Farm income• Farm workers• Land area farmed• Where food comes from• Consumption patterns• Types of consumption• Health related to food• Cost• Modern agriculture production trends• What needs to be done for sustainability?

100 Years of Structural Change in U.S. Agriculture

  1900 1930 1945 1970 2000/02

Number of farms (millions) 5.7 6.3 5.9 2.9 2.1Average farm size (acres) 146 151 195 376 441Average no. of commodities produced/farm 5.1 4.5 4.6 2.7 1.3Farm share of population (percent) 39 25 17 5 1Rural share of population (percent) 60 44 36 26 21

      ----------- Percent ----------Off-farm labor* na 100 d 27 54 93

na=not available.*1930, average number of days worked off-farm; 1945, percent of farmers working off-farm; 1970 and 2000/02, percent of households with off-farm income.

Sources: U.S. Census Bureau, Census of Agriculture, and Census of Population, various issues, 1900-2000; USDA Census of Agriculture, 2002; and B. Gardner, American Agriculture in the Twentieth Century, 2002.

Consolidation in U.S. Food System

• 80% of beef packing market controlled by 4 firms

• 80% of soybean processing controlled by 4 firms

• Top 5 food retailers sell 42% of America’s food (in 1997 it was 27%)

• Changing? Maybe as there has been a recent emphasis on local food

U.S. Food Consumption – 2775 calories/day in 2007, a 28% ↑ since 1970

Food 1970 2007

lbs/person % ↑

Grains 137 192 47

Fruits & Veg 556 687 19

Milk & Milk Prod 564 601 6

Meat, eggs, nuts 225 242 7

Sugar &

Sweeteners 115 142 19

U.S. Population and HealthAre we well fed and healthy?

• 67% Americans are overweight or obese (body mass index of 25 or >)– Compared to 47% in 1970

• Obesity rates by age:– 2-5 – 10%, 6-11 – 20%,12-19 – 18%, . 19 –

34%

• 400,000 premature deaths related to poor diets and effects on heart, cancer and stoke health problems

• Will diets change and how?

U.S. Food Price Trends

• 2008 – greatest increase in prices in 17 years ~ 4.5% ↑

• 2007 – 4% ↑ compared with 2.5% over last 15 years

• U.S. disposable income spent on food was 7.2% in 2006, 225% in Poland, 44% in Egypt

• % of Hunger in U.S. is low• Food riots over food shortages

Has Agriculture Benefited the World?

• Benefits to humanity have been immense• Agriculturalists are principle managers of

useful global lands– They shape the future face of the earth -

hopefully in a positive manner– We must increase yields– Can not compromise environmental integrity or

public health– How to double yield and meet society demands?

Modern Agriculture• 7.0 billion people in world

– Ag feeds 5.5 with 1 billion underfed – reasons?

• By 2050 world population will be ~ 9 billion• Grain yields will need to double

– > inputs of fertilizer, water, pesticides, new cultivars, animal feed

• Total Calories will need to double because of > meat consumption

• Challenges– increasing development throughout world– reducing hunger– improving nutrition– sparing natural ecosystems from conversion to

agriculture

Food Security

Whose Food Security?The World – Countries – households - individuals

World Map of Hunger: 2008 Global Hunger Index (GHI) by Severity

Source: von Grebmer et al., IFPRI 2008.

GHI components:•Proportion of undernourished•Prevalence of underweight in children•Under-five mortality rate

People Affected by Hunger

Source: UN Millennium Project, Hunger Task Force, 2005

AgricultureUnder Attack?

• Agriculture is probably one of the most disruptive human endeavor in changing ecosystems – Add and use high amounts of nutrients

especially - N and P– Nutrients additions will have to increase if

we are to achieve greater yields– Costs of agriculture have usually not been

measured, at least until recently

• Resiliency vs. Productivity

• Self-organization vs. Control

• Feedbacks and Reinforcing Cycles

• Hierarchies operating on Multiple Time Scales

• Systems are likely to be more complicated that they first seem

Thinking In Systems:

Smokey the Bear supports productivity over resilience and attempts to make a dynamic system static…

RESILIENCE: The capacity of a system to absorb shocks

The ADAPTIVE CYCLE: Step 1 in resilience thinking.

Systems can be manipulated to be:More efficient, stable or productive – this is what we tend to do.More RESILIENT – this is what we should do.

Ecosystem Services

• Natural and managed ecosystems provide:– food– fiber– fuel– materials for shelter– recreation– forests and watersheds – climate– atmosphere– nutrient cycling

Agriculture if Done Wrong can:

• Cause:– Pesticide contamination– Nutrient runoff– Species composition changes– Clear cutting– Pollution– Soil degradation– > use of non-renewable energy resources– Loss of useful farm land – Farming being done on marginal land

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4

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1963 1967 1971 1975 1979 1983 1987 1991 1995 1999 2003

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ual g

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ate

(%)

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Source: World Development Report 2008.

Productivity Growth Declining

Nutrient Use Patterns

Increasing Nutrient Utilization

Importance of Nutrients

• High yields dependant on addition of fertilizers

• Between 1960 and 1995 global use of N increased 7 fold and P use increased 3.5 fold

• Their use will increase 3.5 fold by 2050 unless we increase efficiency

• Only 30-35% and 45% of applied N and P taken up by plant – rest goes where ?

Soils and Nutrients• Soil is the most important resource in

agriculture

• Quality soil is essential for increasing yields

• Some say: farmers only need the soil to hold the plant up – we provide everything else necessary to productivity

• Since 1945 – 17% of vegetated land has undergone human induced degradation

Increasing Water Use Efficiency

• 40% of crop production comes from 16% of land that is irrigated

• Irrigation is a great contributor to increased yields

• Problems with dependence on water– Availability– Competition– Abuse of ground water use– Drought

Pest Management

• Important input for increased yields and quality

• All effective pest management tools select for their own extinction

• Must use integrated approaches and a variety of tools

Pesticide Use

Soil EcologySoil Ecology dictates ecosystem processes:

1. Cycling of nutrients-decomposition

-mineralization

-energy turnover

2. Biodiversity – plants, animals, microbes

The diversity and abundance of life in soil exceeds that of any other ecosystem.

Bad Soil Practices

• Too much tillage • Poor fertilizer and water inputs• Limited crop rotations • Decreased fallow periods• No cover or catch crops, legumes, manures,

composts• Result

– Decreased yields– Loss of productive soils

Food Production Increase while Minimizing Environmental Costs

• Increasing Yields• While-

– Increasing Nutrient use efficiency– Increasing water use efficiency– Maintaining and restoring soil fertility– Disease and pest control– Sustainable livestock production– Balance in ecosystem– Law of return

Why Organic Farming?

• Environmental concerns

• Health concerns

• Economic concerns

• Ethics

Organic Agriculture• Organic production should fit into and benefit from nature’s system

• Goals – producing high quality safe food in a manner that tends to preserve the integrity and stability of the biotic community and builds or at least sustains the inherent productive capacity of the soil and biological resources used in the production process

Principles and Practices in Organic Production

• Biodiversity• Diversification and integration• Sustainability• Natural plant nutrition• Natural pest management• Integrity

Organic Agriculture “Alternative strategies for managing plant growth.”

• Soil health (Quality) = Plant health

• Strongly related to soil biology• Soil “Organism” - the Living Soil

– Eats– Breathes– Circulates fluids and nutrients– Reproduces itself

Organic Practices

• What is organic food ?– Produced using renewable resources– Conservation of soil– No antibiotics or hormones used– No use of synthetic chemicals– No use of petroleum based fertilizers– No use of sewage sludge based fertilizers– No bioengineering of crops or livestock– No use of ionizing radiation– Organic label only from certified farms– Handlers and processors must be certified

Benefits of Sustainability and Organic Farming

• Sustainable Agriculture practices– must meet current and future societal

needs for• Food and fiber• Ecosystem services• Healthy lives

– must do this by• Maximizing the net benefits to society when all

costs of agriculture practices are considered

Importance of Plant Physiology Knowledge

• Developing a sustainable and productive agriculture– Next 50 years are critical– Expanding human population– Expanding environmental impacts– Agriculture practices will shape the earth + or -

• How to address this?– What have you learned in Hort 301 that can be

applied to the agriculture challenges posed ?

Methods to Achieving Sustainability

• Agronomic practices – The farmer– Technology – for instance?

• Changing the plant paradigm – The scientist– Improving plants – how?

• Society– Awareness and contributions

Challenges to Making Agriculture Sustainable

• Ways to improve sustainability and meet food needs of world– Nutrients – availability and utilization – Water – availability and utilization– Soil fertility – ways to maintain and

improve– Pest management – reduction in effects– Germplasm – how to improve?– Ecosystem services – how to sustain?

Summary

• Challenges facing Agriculture• Sustainability • How to Address these challenges• Can we Achieving a sustainable

agriculture and world?• What plant physiology knowledge will

help you to contribute to solutions– EITHER AS A PRODUCER OR AS A

SCIENTIST OR AS A CITIZEN?