Agriculture And Energetica Flashcards
How many plants are edible
30,000
How many plant and animal species provide food ?
15 plant and 8 animal species
What percentage of food do animal and plant species provide?
90%
What percent of land is used for food production?
35%
Human labor and draft animals used to produce food for the family?
Traditional
Examples of traditional food production?
Shifting cultivation in tropical forests
Nomadic live stock herding
Tropical trees are cut down and burned to clear land for planting
Traditional (Swidden) Agriculture
What’s the purpose of Traditional (Swidden) Agriculture ?
Remove debris
Ash is high in minerals which help plants grow
What must you have to know if a resource is renewable
Rates
What do you need to ensure a similar yield at each harvest?
Regeneration time
Research and development of technology that increased agricultural production worldwide, beginning in the 1930’s through 1970s
The Green Revolution
What caused the increase in crop yields during the green revolution ?
-New high-yielding varieties of cereals
-Higher use if chemical fertilizers, pesticides and agro-chemicals
- Increased irrigation and mechanization
Large inputs if energy ( fossil fuels, fertilizers, irrigation, and pesticides)
Industrialized agricultural practice
What is needed/ happens with industrialized agriculture?
- large expanses of land
- organic matter removed
- soil is exposed to wind and water erosion
- lost nutrient cycle due to chemical fertilizers
- monoculture is susceptible to pests and plant diseases
An artificial nitrogen fixation process which is the main industrial procedure for the production of amonia?
The harbor process
What do high concentrations of nitrate lead to?
Birth defects
Cancer
Blue baby syndrome
Declining fisheries
What percent of all agriculture is consumed by pests and diseases?
40%
Why was DDT developed?
To control mosquito-borne illnesses
Why did humans begin to do with DDT?
Used it to control outdoor and indoor insects
Aerial spraying ( in pools, fields, etc)
Is DDT easily broken down?
No
What does DDT attach to and therefore do?
Attaches to body fat and travels up the food chain
The process by which toxins are stored in the tissue if living things, and increase in concentration when passed through the food chain?
Bioaccumulation
What was Rachel Carson’s job?
A marine biologist and conservationist
What are Rachel’s writings credited for doing?
Advancing the global environmental movement
What was rachel critical of?
Using large amounts of chemicals without fully understanding their effects.
What did DDT do to birds?
Reduce the thickness of their shells
When was DDT banned for agricultural use in the US?
1972
Change in pesticides effectiveness is caused by what?
Genetic resistance
The differential success of individuals within the population that results from their interaction with their environment
Natural Selection
What characterizes natural selection?
The elimination of inferior individuals
The proportionsl contribution of an individual to future generations
Fitness
What are the 3 conditions of evolution by natural selection?
- Variation among individuals of heritable characteristics
- Offspring inherits variations
3 variation results in differences among individuals in fitness
What are the problems with pesticides?
1 do not kill all individuals
2 The resistant individuals survive and reproduce
3 pesticide becomes useless against initial target
4. typically kill beneficial insects as well as harmful ones
The ability of a pest to withstand exposure to a given pesticide, the result of natural selection favoring the survivors of past pesticide exposure
Pesticide Resistance
How to maximize effects of pesticides and minimize environmental impacts?
Use short lived pesticides
Use pesticides that target certain species
Study life cycles of target pests to determine best time and place to use chemicals
Reduced pesticide use by 75%
Reduced costs by 90%
Increased crop yield
Boll weevil pheromone trap
Using natural predators and parasites to manage pests
Biological pest control
Reduction in reproduction or survival of a species when at low population densities
Allee effect
Combining ecological, biological and chemical methods
Integrated pest management
Food accounts for how much of our ecological foot print?
25%
Food transportation can increase footprint by what percentage?
10
What are sustainable agricultural practices?
Soil conservation
Reduce use of pesticides/ use manure
Crop rotation
Water conservation
