apes ch 13 l.
Skip this Video
Download Presentation
APES Ch 13

Loading in 2 Seconds...

play fullscreen
1 / 37

APES Ch 13 - PowerPoint PPT Presentation

  • Uploaded on

APES Ch 13. Food, Soil Conservation and Pest Management. Food Security and Nutrition. 1 in 6 people in developing countries does not get enough food (most likely due to poverty) Food security :

I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
Download Presentation

PowerPoint Slideshow about 'APES Ch 13' - connor

Download Now An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.

- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
apes ch 13

APES Ch 13

Food, Soil Conservation and Pest Management

food security and nutrition
Food Security and Nutrition
  • 1 in 6 people in developing countries does not get enough food (most likely due to poverty)
  • Food security:
    • Most developing nations can not provide food security to all their people b/c they cant produce enough food or they can’t afford to import.
    • Also depends on reducing harmful environmental effects of agriculture (erosion, aquifer depletion).
food security and nutrition3
Food Security and Nutrition
  • Chronic hunger:
  • Malnutrition:
  • UN Food and Agriculture Organization (FAO) goal is to reduce the # of hungry and malnourished to 400 million by 2015 (as of 2005 there were 852 million)
  • FAO estimated that 6 million children died each year due to lack of essential food.
food security and nutrition4
Food Security and Nutrition
  • Famine:
    • Can lead to mass migrations
    • Usually caused by crop failure due to drought, flood, war or other catastrophic events.
  • Overnutrition:
    • Can cause some of the same problems as under-nutrition (lower life expectancy, diseases, lower life quality)
food production
Food Production
  • 3 systems that supply most food:
    • Croplands – 77%
    • Rangelands – 16%
    • Oceanic fisheries and aquaculture – 7%
    • All 3 systems have increased since 1960 due to better technology and other advances (fertilizers, pesticides, irrigation).
    • May not be able to produce enough food by 2050 for the possible 8.5 billion people.
      • Environmental degradation, pollution, lack of water, overgrazing, overfishing, rising temps., increasing fuel costs
food production6
Food Production
  • Only 14 plants and 9 terrestrial animal species supply an estimated 90% of worlds food.
    • 3 types of grain (wheat, rice and corn) provide more than 50%
      • Many people can’t afford meats, milk and cheese products.
    • Fish and shellfish make up only 7%
food production7
Food Production
  • Industrialized agriculture (high input):
    • 80% of worlds food supply is produced this way
  • Plantation agriculture:
    • Cash crops (bananas, soybeans, sugarcane, cocoa, peanuts and coffee
    • Must clear tropical rain forests to plant
  • Livestock
    • Most are in feedlots
    • Use lots of energy and water and produces lots of animal waste and water pollution

Natural Capital


Ecological Services

Economic Services

• Help maintain water flow and soil infiltration

• Food crops

• Provide partial erosion protection

• Fiber crops

• Can build soil organic matter

• Crop genetic resources

• Store atmospheric carbon

• Jobs

• Provide wildlife habitat for some species

Fig. 13-6, p. 276

food production9
Food Production
  • Traditional agriculture (low input)
    • Traditional subsistence agriculture:
    • Traditional intensive agriculture:
    • Interplanting:
      • Reduces chance of losing all of the years food supply
      • Polyvarietal cultivation:
      • Intercropping:
      • Agroforestry (alley cropping):
      • Polyculture:
        • Keeps soil covered, less fertilizer and water use, less pesticides.
soil erosion and degradation
Soil Erosion and Degradation
  • Topsoil:
    • Naturally renewable but very slow (several 100 yrs to make 1 inch)
  • Soil erosion:
    • Increases when vegetation is removed
    • Sheet erosion:
    • Rill erosion:
    • Gully erosion:
    • Major effects of erosion
      • Loss of soil fertility
      • Water pollution due to sedimentation runoff

Soil Erosion and Degradation









Economic losses


Lower living standards

Soil compaction

Natural climate change

Environmental refugees

  • Desertification:
    • 1/3 of the worlds land and 70% of all dryland are suffering from desertification.

Fig. 13-12, p. 280







Less permeable clay layer



1. Irrigation water contains small amounts of dissolved salts

1. Precipitation and irrigation water percolate downward.

2. Evaporation and transpiration leave salts behind.

2. Water table rises.

3. Salt builds up in soil.

Fig. 13-13, p. 281



Soil Salinization



Reduce irrigation

Flush soil (expensive and wastes water)

Stop growing crops for 2–5 years

Switch to salt-tolerant crops (such as barley, cotton, sugarbeet)

Install underground drainage systems (expensive)

Fig. 13-15, p. 281

sustainable agriculture through soil conservation
Sustainable Agriculture Through Soil Conservation
  • Soil conservation:
    • Eliminating plowing and breaking up and tilling is key to reduce soil erosion.
    • Conservation-tillage farming:
    • Terracing:
    • Contour farming:
    • Strip cropping:
    • Wind breaks:
    • Use cover crops
sustainable agriculture through soil conservation15
Sustainable Agriculture Through Soil Conservation
  • Organic fertilizer:
    • Animal manure:
    • Green manure:
    • Compost:
  • Commercial inorganic fertilizer:
    • Contain nitrogen, phosphorus, and potassium
  • Crop rotation:
    • Also helps reduce erosion
the green revolution and its environmental impact
The Green Revolution and its Environmental Impact
  • Green Revolution:
    • Plant monoculture plants
    • Use large amounts of fertilizer, pesticides and water for higher yield
    • Increase the # of crops grown per on plot of land through multiple cropping
  • 1st Green Revolution took place between 1950-1970 in developed countries
  • 2nd Green Revolution has been taking place since 1967 in developing countries mostly in tropical areas.
the green revolution and its environmental impact17
The Green Revolution and its Environmental Impact
  • Pros
    • Has produced more food for growing population
    • Many countries are now self sufficient with food
    • Use less land for larger yield
  • Cons
    • More fertilizer, pesticides and water
    • To expensive for subsistence farmers
    • If expanded- not enough workers (more people moving to cities for jobs)
    • More irrigation which can lead to more salinization
the green revolution and its environmental impact18
The Green Revolution and its Environmental Impact
  • More land can be planted with crops but significant expansion of cropland is unlikely over the next few decades for economic and ecological reasons
  • Loss of agrobiodiversity – the worlds genetic variety of animals and plants used to provide food
    • Ex: India use to plant 30,000 different types of rice, now only 10 types are used.
the green revolution and its environmental impact19
The Green Revolution and its Environmental Impact
  • Modern agriculture violates the 4 Principles of Sustainability
    • Depends heavily on nonrenewable fossil fuels
    • Too little recycling of crop and animal wastes
    • Accelerates soil erosion
    • Does not preserve agrobiodiveristy
    • Disrupts natural species interactions that help control population sizes and pests.

Biodiversity Loss


Air Pollution

Human Health


Loss and degradation of grasslands, forests, and wetlands


Water waste

Nitrates in drinking water

Greenhouse gas emissions from fossil fuel use

Aquifer depletion

Loss of fertility

Pesticide residues in drinking water, food, and air


Increased runoff and flooding from cleared land

Other air pollutants from fossil fuel use



Fish kills from pesticide runoff

Sediment pollution from erosion

Contamination of drinking and swimming water with disease organisms from livestock wastes

Greenhouse gas emissions of nitrous oxide from use of inorganic fertilizers

Fish kills from pesticide runoff

Killing wild predators to protect livestock

Surface and groundwater pollution from pesticides and fertilizers

Belching of the greenhouse gas methane by cattle

Loss of genetic diversity of wild crop strains replaced by monoculture strains

Bacterial contamination of meat

Overfertilization of lakes and rivers from runoff of fertilizers, livestock wastes, and food processing wastes

Pollution from pesticide sprays

Fig. 13-18, p. 285

the gene revolution
The Gene Revolution
  • For years the use of crossbreeding through artificial selection to develop genetically improved varieties of crop strains has been used.
  • Now genetic engineering is being used (takes a gene of 1 species and inserts it into the DNA of another species)
    • Takes ½ the time and cost less then crossbreeding
      • Ex: potatoes resist disease because they contain a certain chicken gene.
the gene revolution22
The Gene Revolution
  • Nontraditional foods could help provide essential nutrients and lower the need for some crops.
    • Winged bean has many edible parts and requires little fertilize.
    • Quinoa plant is called the worlds most nutritious plant and can resist frost and droughts and can grow in saline soils.
    • Insects are a great source of protein and are easy to “farm”


Genetically Modified Crops and Foods

Projected Advantages

Projected Disadvantages

Need less fertilizer

Irreversible and unpredictable genetic and ecological effects

Need less water

Harmful toxins in food from possible plant cell mutations

More resistant to insects, disease, frost, and drought

New allergens in food

Grow faster

Lower nutrition

Can grow in slightly salty soils

Increased development of pesticide-resistant insects and plant diseases

Less spoilage

Better flavor

Can create herbicide-resistant weeds

Need less pesticides

Tolerate higher levels of herbicides

Can harm beneficial insects

Higher yields

Lower genetic diversity

Fig. 13-19, p. 287

producing more meat
Producing More Meat
  • Between 1950-2005 meat production increased more then 5 fold and is likely to double again by 2050 as more people become affluent.
  • 2 systems for raising livestock
    • Graze on grass
    • Feedlots- raise in densely packed areas by feeding them grain and/or fish meal.
      • Animals given antibiotics and steroids
      • Accounts for 43% of worlds beef, 50% of pork and 68% of eggs, and 75% of poultry production.
      • Solutions: people can eat more poultry and fish rather then beef, establish more humane ways to raise livestock in feedlots.


Animal Feedlots



Increased meat production

Need large inputs of grain, fish meal, water, and fossil fuels

Higher profits

Concentrate animal wastes that can pollute water

Less land use

Reduced overgrazing

Reduced soil erosion

Antibiotics can increase genetic resistance to microbes in humans

Help protect biodiversity

Fig. 13-21, p. 289

producing more meat26
Producing More Meat
  • Catching and raising more fish and shellfish.
    • Fisheries:
    • 3rd major food producing system.
      • 2/3 comes from oceans, lakes, rivers and ponds
      • 1/3 comes from aquaculture
    • Scientists project a decline in global fish catch due to overfishing, coastal water pollution and wetland destruction
producing more meat27
Producing More Meat
  • 125 out of 128 depleted fish stocks could recover with careful management.
  • Ecolabels help shoppers identify wild fish that have been caught by more sustainable fishing practices.
    • Walmart said that within 5 yrs it would sell only fish certified by the Marine Stewardship Council)
  • Govt's subsides given to the fishing industry are a major cause of overfishing.
    • Subsides $ should be used to buy out some fishing boats and retrain their crew for other occupations
producing more meat28
Producing More Meat
  • Aquaculture:
    • Fishing farms:
    • Fishing ranches:
    • Mainly carp in China and India, catfish in US, tilapia and shellfish in other countries





High efficiency

Needs large inputs of land, feed, and water

High yield in small volume of water

Large waste output

Destroys mangrove forests and estuaries

Can reduce overharvesting of conventional fisheries

Uses grain to feed some species

Low fuel use

Dense populations vulnerable to disease

High profits

Tanks too contaminated to use after about 5 years

Profits not tied to price of oil

Fig. 13-24, p. 292



More Sustainable Aquaculture

• Use less fishmeal feed to reduce depletion of other fish

• Improve management of aquaculture wastes

• Reduce escape of aquaculture species into the wild

• Restrict location of fish farms to reduce loss of mangrove forests and estuaries

• Farm some aquaculture species in deeply submerged cages to protect them from wave action and predators and allow dilution of wastes into the ocean

• Certify sustainable forms of aquaculture

Fig. 13-25, p. 293

solutions moving toward global food security
Solutions: Moving Toward Global Food Security
  • People in urban areas could save money by growing more of their own food.
  • We can waste less food (70% of food is wasted through spoilage, inefficient processing and plate waste).
    • US households throw away food worth as much as $43 million/yr – twice the $24 million it would take to eliminate global hunger
solutions moving toward global food security32
We can increase global food security by –

Slow pop growth

Reduce poverty

Reduce soil erosion

Halt desertification

Eliminate overgrazing

Slow removal of groundwater

Protect cropland from development

Reduce rate of global warming

Solutions: Moving Toward Global Food Security
protecting food resources pest control
Protecting Food Resources: Pest Control
  • Pest:
  • Only 100 species cause 90% of the damage to crops
  • In nature natural enemies control 98% of the potential pests species
  • Pesticides:
protecting food resources pest control34
Protecting Food Resources: Pest Control
  • 2 generations of pest control
    • 1st generation (copy nature): before 1930s many pesticides were derived from organisms (mostly plants). They were natural defenses.
    • 2nd generation: the development of pesticides in labs. Started in 1939 when DDT was discovered. Some lab made pesticides last in environment for years and can biologically magnified in food chains.
    • ¾ of pesticides is used for crops, ¼ is used for homes, gardens, and golf courses.
    • Federal Insecticide, Fungicide, Rotenticide Act (FIFRA) is suppose to assess the health risks of the active ingredients in pesticide products.


More Sustainable Aquaculture

• Use less fishmeal feed to reduce depletion of other fish

• Improve management of aquaculture wastes

• Reduce escape of aquaculture species into the wild

• Restrict location of fish farms to reduce loss of mangrove forests and estuaries

• Farm some aquaculture species in deeply submerged cages to protect them from wave action and predators and allow dilution of wastes into the ocean

• Certify sustainable forms of aquaculture

Fig. 13-25, p. 293

protecting food resources pest control36
Protecting Food Resources: Pest Control
  • Other ways to control pests:
    • Fool pest
    • Provide homes for pest enemies
    • Implant genetic resistance
    • Bring in natural enemies
    • Use insect perfumes
    • Bring in hormones
    • Scald pests


Sustainable Organic Agriculture



High-yield polyculture

Soil erosion

Soil salinization

Organic fertilizers

Aquifer depletion

Biological pest control



Integrated pest management

Loss of biodiversity

Efficient irrigation

Loss of prime cropland

Perennial crops

Food waste

Crop rotation

Subsidies for unsustainable farming and fishing

Water-efficient crops

Soil conservation

Population growth

Subsidies for sustainable farming and fishing


Fig. 13-33, p. 302