Ch. 11 – Producing Enough Food for the World
Case Study: Food for China
China’s History and Current Statistics
1.3 billion 1.5 billion by 2025? Area harvested for rice decreased from
31.1 million ha to 29.3 million ha Impact of increased demand for world
grain supplies? 1959-1961 30 million starved to death Attempt to slow growth one couple, one
child policy 1980 – 1995 total fertility rates dropped
and annual grain production increased
Reasons for concern
Flooding of farmland due to construction of Three Gorges Dam
Building of roads, railroads, and manufacturing plants
Water crisis Chinese are eating higher on the
food chain
Themes
Human population Global perspective Sustainability Science and values
11.1 Can We Feed the World?
Main threat to existing land in agricultural production?
- human development pressuresIf world population doubles?Methods?If we cannot double production??
Dig For Victory
Google Image Result for http://3.bp.blogspot.com/-0yXfnAl_CDk/Tace8OC7RmI/AAAAAAAADV8/LUzjN3lp4aQ/s1600/allotment+4.jpg
Vertical Farming
The Vertical Farm Project - Agriculture for the 21st Century and Beyond | www.verticalfarm.com
11.2 How We Starve
- undernourishment vs malnourishment
- protein – source vs cost- supply vs distribution – impacted
by?- solutions?
11.3 – What We Eat and What We Grow
1. Crops – 6 of 14 of 200 of 3,000 of 500,000
a) wheat, rice, maize, potatoes, sweet potatoes, manioc, sugarcane, sugar beet, common beans, soybeans, barley, sorghum, coconuts, and bananas
Rangeland vs Pasture
provides food for grazing and browsing animals without plowing and planting
plowed, planted, and harvested to provide forage for animals
May I help you?
No thank you, I was just
browsing.
2. Aquaculture
historically hunted – not sustainable
the farming of food in aquatic habitats – can be very productive
Mariculture – the farming of ocean fish
http://www.npr.org/2011/04/11/135324866/salmon-farming-in-chile-impacts-fishermen-environment
11.4 An Ecological Perspective on Agriculture
How do agroecosystems differ from natural systems?
1. Stop ecological succession at an early stage – requires time and effort
2. Monoculture – vulnerable to disease, drains soil of particular nutrients(crop rotation)
3. Planting in neat rows – easier for insects
4. Simplifies biological diversity and food chains
5. Plowing – exposes soil to erosion, disturbs physical structure
6. Genetically modified crops – a novel situation
11.5 – Limiting Factors
Ideal soil composition = required chemical elements
pores for air and water high organic content varied particle size
Liebig’s law – growth is affected by one limiting factor at a time
Synergistic Effect – a change in the availability of one resource affects the response of an organism to some other resource
Ex) Soil lacks nitrogen- nitrogen needed to make protein(enzyme)--- enzyme is needed to take up and use phosphorus
Macro vs micronutrients
Required by all living things in relatively large amounts
S, P, Mg, Ca, K, N, O, C, and H
Required in small amounts
Ex) Molybdenum, copper, zinc
11.6 – The Future of Agriculture
- History of agriculture a. Resource-based – based on biological
technology, conservation of land, water, and energy(10,000 years ago)
b. Mechanized – high demand for resources(18th-19th centuries)
c. Return to resource-based(20th century)
d. Organic and genetically engineered crops(present)
11.7 – Increasing the Yield per Acre
The Green Revolution – development of crops with:
a. higher yields b. better resistance to
disease c. better ability to grow
under poor conditions. Improved Irrigation - drip irrigation,
hydroponics
11.8 Organic Farming
3 qualities: a) more like natural ecosystems
than monocultures b) minimizes negative
environmental impacts c) food does not contain artificial
compounds
What is organic?
Organic is a labeling term that indicates that the food or other agricultural product has been produced through approved methods that integrate cultural, biological, and mechanical practices that foster cycling of resources, promote ecological balance, and conserve biodiversity. Synthetic fertilizers, sewage sludge, irradiation, and genetic engineering may not be used
Organic Farms in New Jersey
http://www.new-jersey-leisure-guide.com/organic-farms.html
11.9 Alternatives to Monoculture
Climate predictions dictate hybrid seed choices
Trade off long-term stability for a very high productive year
11.10 Eating Lower on the Food Chain
Eating lower on the food chain
Must consider soil conditions – can it sustain crops
Animals are a major source of protein
Animals are also used for transportation, a source of wool, leather and fertilizer
11.11 Genetically Modified Food
3 practices: a. faster and more efficient ways to
produce new hybrids b. introduction of the “terminator”
gene c. Transfer of genetic properties
from different forms of life
Goals of genetic modification of crops
Development of strains with the same symbiotic relationship as legumes
Development of strains with improved tolerance to drought, cold, heat, and toxic chemicals
Development of strains that produce their own pesticides
You decide
http://www.pbs.org/wgbh/harvest/exist/
Visit this website and make your decision based upon the information presented. You will be asked for your decision on the test and you must back it up with information from this website.
11.12 Climate Change and Agriculture
Climates suited to agriculture may move further north less than optimal soils
Increased temperatures increased rates of evapotranspiration supplying water for irrigation a problem