2 - Impacts on the Biosphere Flashcards
Define the Biosphere:
… is the global ecosystem composed of living organisms (biota) and the nonliving (abiotic) factors from which they derive energy and nutrients.
What kind of effects do we look at the agricultural impacts on living organisms?
- Direct
- Indirect
What are the 4 main negative impacts of agriculture on the biosphere?
- Habitat loss, fragmentation and degradation
- Pesticide effects on biodiversity/ human health
- Negative impacts of crop protection on animals
- Possible consequences of selective breeding and genetic engineering on biodiversity and human health
What are the positive impacts of agriculture on the biosphere?
- Biodiversity
- Biological Nitrogen Fixation (BNF)
- Food Production
- Habitats
- Optimize Synergies
- Preserve Gene Resources
What is BNF?
Biological Nitrogen Fixation
Define BNF:
Atmospheric nitrogen is converted to ammonia by certain microorganisms.
What kind of plants are capable of BNF?
Legumes
How does BNF benefit agriculture?
- Less N fertilizer application for current and future crops
- Enhance nitrogen in soils
What is Mychorrhizae an example of?
BNF
What is Mychorrhizae?
The symbiotic relationship between fungi and plants.
How does Mychorrhizae work?
The fungi colonize the root system of a host plant, providing increased water and nutrient absorption capabilities while the plant provides the fungus with carbohydrates formed from photosynthesis
Overall, farmland covers ____ of the world’s land area.
38%
True or False: World’s original forests are still being removed at a rate x10 times greater than rate of regrowth
True
What are the 4 types of habitat loss, fragmentation, and degradation from agriculture?
- Aquaculture
- Deforestation
- Desertification
- Intensive Monocultures
What do you call the areas with extremely high biodiversity?
Biodiversity Hotspots
True or False: About 12 million hectares of land is lost each year to desertification because of unsustainable agricultural practices
True
Define Intensive Monocultures:
Large-scale clearing of natural habitats to make room for intensive monocultures
Principal cause of habitat destruction is
___________________.
clearing lands for agricultural use
Provide 4 examples of large scale habitat loss and fragmentation:
- Conversion of lowland rainforests in Africa, Latin
America, and Asia (Malaysia, Indonesia) to oil palm
plantations - Conversion of the Amazon rain forests and Brazilian
savanna to soybean and cattle farms. - Siting of fish farms in the migratory routes of wild
salmon. - Destruction of mangrove forests to make space for
shrimp farming
What kind of animals do oil palm plantations pose a threat to?
- Elephants
- Rhinoceros
- Orangutans
- Tigers
What are the 5 specific problems with oil palm cultivation on biodiversity?
- Destruction of habitats for rare/ endangered species.
- Elimination of wildlife corridors.
- An increase in human-wildlife conflict as populations of large animals
- Reduced biodiversity in plantations
- Use of poisons to eliminate rats within oil palm plantations, which are toxic to other animals.
What does the conversion of the Amazon rain forests and Brazilian savanna to soybean and cattle farms do?
- Fragmentation of the rain forests and wooded grassland
-
Isolate animals in fragmented lands; Edge species are
more affected
What are some negative impacts of fish farms on the wild salmon?
- Infections from sea lice, bacteria and viruses that
thrive in fish farms are spreading to wild salmon; - Escaped farmed salmon compete with wild salmon in the ocean
- Fish farms pollute marine habitat with feces,
antibiotics and uneaten food.
Which meat source is the least sustainable?
- Beef
- Pigs
- Chicken
- Fish
Define Mangrove Forests:
Trees and shrubs that grow in salty coastal sediment
Why have mangrove forests been cleared in Asia and Latin America?
Mangrove forests have been cleared to make space for shrimp farms
What are some benefits of mangrove forests?
- Absorb Carbon Dioxide
- Counteract Rising Sea Levels
- Lumber
- Protect coastlines
- Sustain sea life
- Slow climate change
About ____ of mangroves worldwide have been lost
since 1980, in order to make room for the artificial shrimp
ponds
1/5
Most pesticides are a _______ by design.
Toxin
Why are pesticides bad for human health?
- threaten our well-being (eating or destroying the crops)
- have a role in human disease (mosquitoes and flies; vectors of many human diseases).
What are the 2 spectrums used to classify pesticides?
- Broad
- Narrow
Define Broad-spectrum pesticides:
Broad-spectrum pesticides kill a wide variety
of pests.
Define Narrow-spectrum pesticides:
Narrow-spectrum pesticides target specific
pests.
True or False: Pesticide DDT - played a significant role in the reduction in malaria in several parts of the world
True
What does the impact of pesticides on biodiversity and human health depend on?
- Biomagnification
- Distribution
- Persistence
- Toxicity Spectrum (Broad v. Narrow)
What is the grasshopper effect?
Pesticides may get transported from warmer to colder regions of the Earth, particularly the poles and mountain tops.
What are the 2 types of effects pesticides can have on human health?
- Acute
- Chronic
What are some Chronic effects of pesticides on human health?
- Birth Defects
- Male Sterility & Miscarriages
- Respiratory problems
- Skin Problems
What are some negative effects of crop protection on animals?
- Animals are killed to prepare land for use.
Why can selective breeding be dangerous for biodiversity?
- Artificial selection reduces genetic variation in a population over time
- Selectively bred organisms may become too susceptible to diseases or to environmental changes
Why is selective breeding used in agriculture?
- Aesthetics
- High yields
- Larger Animals
- Seedless fruits
- Tastier
What is a Transgenic Organism?
Produces genetically modified organisms (GMOs) with new traits.
What is the GMO process?
Removing DNA from one organism and splices it into the chromosomes of another.
How are GMOs beneficial?
- Faster Growing
- Nutrient Increase
- Pest-resistance and wider stresstolerance levels.
What are Bt crops?
The protein produced by Bt crops acts as a pesticide for selective target pests. Comes from a naturally occurring microorganism called Bacillus thuringiensis or “Bt.”
What is the “Bt” of Bt Crops?
Bacillus thuringiensis or “Bt.”
What are 4 crops with Herbicide tolerance?
- Enlist Crops
- Extend Crops
- Liberty-Link Crops
- Round-up Ready Crops
What type of crop with herbicide tolerance is “Transgenic crops that are resistant to the herbicide glyphosate”?
Round-up Crop
What type of crop with herbicide tolerance is “Transgenic crops that are tolerant to the herbicide Liberty (broad-spectrum)”?
LibertyLink Crops
What type of crop with herbicide tolerance is “Transgenic crops that are tolerant to the herbicide glyphosate and 2,4-D”?
Enlist Crops
What type of crop with herbicide tolerance is “Transgenic crops that are tolerant to the herbicide glyphosate and dicamba”?
Xtend Crops
What did Transgenic crops introduce into farming practices?
Facilitated the adoption of no-till farming because tillage is not needed for weed control.
What is an example of Genetically Modified animals?
GMO Salmon, to increase the speed at which the fish grows- Salmon with added growth hormone gene grow 7X faster than their wild counterparts
Who is Daisy, the GM Cow?
A genetically modified cow whose milk lacks a substance that causes allergic reactions in people has been created by scientists in New Zealand.
What are some reasons why GMOs could compromise biodiversity?
- Directly harm other organisms
- Indirectly harm biodiversity
- Increase Herbices Use
- Outcrossing
- Resistance to toxins
- Reduce the cultivar biodiversity
What is Out-crossing?
GM plants may pass their new traits on to wild relatives
What is out-crossing an example of?
Reasons why GMOs could compromise biodiversity
How can GMO organisms directly harm other organisms?
Some GM crops engineered to be resistant to pests may harm insects that are not targets but still consume the crop, and thus effect biodiversity.
How can GMO organisms indirectly harm biodiversity?
Through a reduction in the insects that serve as a source of food for other wildlife, such as birds.
What is an example of a pest developing resistance to toxins?
The Pink Bollworm butterfly, fought toxins of Bt cotton!
How do GMOs reduce cultivar biodiversity?
By widespread use of only a few GM crop varieties
Producing food and fibre on a sustainable basis and repair the damage caused by destructive practices can be ________, __________, __________, and ___________.
- Profitable
- Low-input
- Environmental Friendly
- Beneficial to society
Sustainable agriculture includes (3):
- Biological Control
- Biofertilizers
- Integrated Pest Management
How is Biological Control sustainable?
It can use natural features to control weeds, pests. (Hormones, pathogens)
What is the Neem Tree an example of?
Biological Control
- it provides natural pesticides
Define Biofertilizer:
A substance which contains living microorganisms to increase the availability or primary nutrients to host plant
What does Integrated Pest Management aim its target at?
- Avoid broad spectrum controls
- Minimize use of chemical
- Preventative Practices
- Use Bt, natural predators, pheromones
What is a Canadian example of Integrated Pest Management?
Nova Scotia Forestry Division closely monitor populations of spruce budworms and gypsy moths
What % of farming does organic farming represent?
0.8%
How does organic farming treat their produce?
- Access to the outdoors
- No steroids or hormones
- Raised on organic feed
How does Organic Farming leave the soil?
Leaves soil healthier than intensive, chemical-based mono-culture cropping
What is a hesitation with Organic Farming?
Some doubt whether organic growers can
produce enough to feed everyone.
What are the 5 main effects of pesticides on biodiversity?
- Acute Wildlife Poisoning
- Accumulation in Tissues
- Grasshopper Effect
- Kill beneficial organisms
- Reduction of Eggshell
- Reduce Floral Diversity
