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Lecture Outline
• 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
Sustainable Agriculture is Basis of Farming
• Sustainable agriculture must:
– Preserve the capacity of the land to meet the needs of humans and other species (Ecology).
– Preserve farming as an economically viable occupation and a rewarding lifestyle (Economy).
– Preserve the integrity of rural communities (Society).
Patterns of 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?
Consolidation of U.S. Agriculture Production
• Farmers ~ 2% of population, average age ↑
• 8% of farms account for 68% of production
• 3 out of 4 farm household earn majority of income from off-farm employment
• In 2000, 19¢ of each $ spent on food returned to farmer
• 2008 – 53% of farm workers were illegal
• 2008 – 434 million A, 1997 – 454 million A
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%)
U.S. Food Consumption – 2700 calories/day in 2000, a 24.5% ↑ since 1970
Food 1970 2005
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
USDA Recommendations
• Grains – at least ½ whole grains
• Vegetables – eat dark green, orange and leafy types
• Fruits – choose a variety of fruits, < juice
• Milk – choose fat-free and low-fat
• Meat – choose lean meats and low-fat
• Sugars – avoid corn sweeteners
U.S. Population and Health
• 2/3 of Americans are overweight or obese (body mass index of 25 or >)
Compared to 47% in 1970• Obesity rate has doubled since 1970
from 15% to 30% for adult population• 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• Recent food riots in world over food
shortages
Modern Agriculture• Feeds 6 billion people• By 2050 world population will be ~ 9 billion• Grain yields will need to double
– > inputs of fertilizer, water, pesticides, new cultivars
• Challenges– increasing development throughout world– reducing hunger– improving nutrition– sparing natural ecosystems from conversion to
agriculture
Benefits of Agriculture
• 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? Yield doubling and society demands
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
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
Benefits of Sustainability
• 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
World Population Now and in the Future and Food Supplies
• 2000 – 6.1 Billion• 2050 – 9.2 Billion• 99% of growth will be in less developed
countries• Food Supplies are strained in 2008• Is current farming sustainable?• Reasons yes or no?• Solutions - hope or none?
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
Food Production and Environmental Costs
• Increasing Yields• 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
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 ?
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
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
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.
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
Ecological Perspective: “Alternative strategies for managing plant growth.”
Biological
Chemical
Physical
Weathering
N-fixation
Mycorrhizae
Soil mixing
Aggregation
Mineralization
HumusFormation Aeration
Ecological Perspective:
• Sustainable Agriculture demands a holistic perspective:
• Don’t treat the symptoms, manage the cause!
Soil Farmers
Water
Crops
Wildlife
Livestock
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
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
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?