Envi Sci: Unit 5 Agriculture (REAL) Flashcards
Green Revolution
A period of significant agricultural advancements in the mid-20th century that aimed to increase food production through the use of modern farming techniques
GMOS
Removes DNA from one organism and splices it into the chromosomes of another.
GMO Pros:
- Speeds up production and amount able to be produced
- Can build resilience to frost, drought, low nutrient soil
- Add vitamins
GMO Cons:
- Lack of Genetic Diversity→ vulnerability
- Favors the rich, tech is expensive
- Hurts developing countries
Fertilization - Organic Pros & Cons
The process of adding nutrients to soil to help plants grow.
Organic Pros
-ecologically friendly
-cost effective
-eases acidity of soil
Organic Cons
-Low nutrient content, slow decomposition
Fertilization - Chemical Pros & Cons
The process of adding nutrients to soil to help plants grow.
Chemical Pros
-better performance/growth rate
-raises soil fertility
Chemical Cons
-More expensive
-acidification
-water pollution, eutrophication
-reduces microbes in soil
Irrigation Process: Drip
Water is released from a small hose, less than 10% water lost, but has a high cost and labor
Expensive, best for small scale. Least amount of water is lost, but is labor intensive to setup and maintain.
- Good for a small garden, not large scale commercial crop use
Irrigation Process: Spray
Water is released from a sprinkler after being pumped up from a source. Uses machines or computerization and requires fossil fuels and is more efficient than flood and furrow
Expensive, requires maintenance of sensors and computer systems and equipment but improves efficiency and is unlikely to cause waterlogging
- Farming corporation with lots of money.
- Needs to have capital to spend
Irrigation Process: Furrow
Water is pumped or flows through rows of crops - this method is low tech, prevalent and easy to do, but results in high loss of water due to evaporation and runoff
Cheap, easy to install, and maintain. Most evaporative loss which may result in salinization.
- Used for row crops especially when labor and/or money is limited.
Irrigation Process: Flood
Most appropriate for water tolerant crops, such as rice, alfalfa - this method floods fields, causing waterlogging - loses 20% of water to evaporation and runoff.
Easy to do, but only appropriate for some crops. May lead to waterlogging if drainage is poor
- Farmer grows water-tolerant crops. His soil is well draining and he does not grow additional crops.
Pesticides
Chemicals that kill biological pests
Pesticides Pros
- Kill diseased pests
- Increase food supplies
- Effective, fast acting
Pesticides Cons
-Accumulate in food chain
-Pests develop resistance
-Pesticide Runoff
IPM
Integrated Pest Management, an environmentally-friendly approach to managing pests. IPM can be used in homes, gardens, farms, forests, and other settings.
IPM Pros
- Reduces chemicals being used
- May reduce # of pesticide resistant insects
- Only uses chemicals if necessary
- Long term benefits (lower cost for chemicals, better for environment & human health)
IPM Cons
- Individual use must be educated about the options
- Takes more time to initiate than simply “spraying for pests”
- Must be closely monitored for best results
- Natural enemies of pests may become pests themselves
IPM Chemical
Conventional: pesticides that kill on contact
Biorational: repellents, oils, microbials, etc.
IPM Biological
Predators, parasites
IPM Physical - Mechanical
Flea/lice combs, screens, proper clothing
IPM Cultural
Good sanitation, habitat change
Tilling
Preparing the soil for the cultivation of seeds by digging, ploughing & overturning the soil
-disrupts soil structure
-speeds up surface runoff and erosion
Slash and Burn Farming
A farming method that involves cutting down and burning trees and plants to clear land for growing crops
-loss of habitat
-air pollution through releasing of carbon dioxide
Fertilizers (environment damage)
Natural or artificial substance containing the chemical elements that improve growth and productiveness of plants
-water pollution through runoff
-soil degradation
-air pollution
Waterlogging
Happens when an area is flooded with water, usually due to poor drainage or heavy rainfall. This can damage crops, infrastructure, and transportation.
Salinization
The increase of salt concentration in soil and is, in most cases, caused by dissolved salts in the water supply.
This supply of water can be caused by flooding of the land by seawater, seepage of seawater or brackish groundwater through the soil from below.
Interfering with nitrogen uptake, reducing growth and stopping plant reproduction
Desertification
Human activities that contribute to desertification include the expansion and intensive use of agricultural lands, poor irrigation practices, deforestation, and overgrazing
Explain why meat production is less efficient than plant agriculture
-1.5 billion cattle, raised specifically for meat production worldwide, emit at least 231 billion pounds of methane into the methane into the atmosphere each year via belching or farting
Meat production often requires extensive grasslands, which is often created by cutting down trees, releasing carbon dioxide stored in forests
Water consumption: water that animals drink and the water for crops
Land: grazing cattle can impact erosion rates
Habitat: clear cutting forests to make room for cattle destroys habitats
Antibiotics make spread to humans through infected meat and it may be released into the atmosphere
CAFOS
Animals are concentrated in an enclosed area and fed grain or fish meal
CAFOS Pros
Pros:
less land for more meat, higher profits, less habitat loss, overgrazing and erosion
CAFOS Cons
Cons:
large inputs of grain, water and fossil fuels, concentrated animal waste, overuse of antibiotics and hormones
Free Range Grazing Pros & Cons
Pros:
More environmentally friendly
Ethical eating
Cons:
uses lots of land, produces less meat, overgrazing can occur and lead to erosion and desertification, threats from predators, expensive
Chemical Pesticides Pros & Cons
Pros:
higher yield of crops, larger profits for farmers, and cheaper food for consumers
Cons:
bioaccumulation of chemicals in organisms, genetic resistance to chemicals in pesticides, and biomagnification in the food chain
Contour Plowing
Follows the contours of hills and slopes, rather than orienting crop rows up and down a slope
Windbreaks
“wind fences” are used to reduce wind speeds over erodible areas such as open fields, industrial stockpiles, and dusty industrial operations
Perennial Crops
Any plant that persists for several years, usually with new herbaceous growth from a part that survives from growing season to growing season
No-Till agriculture
Create a channel that is just spacious enough for seeds to be planted, minimizing soil disturbance
Strip Cropping
The planting and growing of alternating strips of erosion- resistant crops with strips of erosion-prone annual crops
Crop rotation
Planting a different crop on a particular piece of land each growing season
Green Manure
Growing plants and then incorporating them back into the soil, which enhances soil fertility and structure
Limestone
Changing the soil pH when it is mixed in with the top 5 inches of soil, which means it’s easier to adjust your soil’s pH before planting grass seed or laying sod than it is to add it to an established lawn
Aquaculture
Breeding, raising, and harvesting fish, shellfish, and aquatic plants
Aquaculture Pros
Pros:
smaller carbon footprint, and require less land & fresh water
Aquaculture Cons
Cons:
displacement of native species, competition for space and food, & pathogens spread
