Environmental science after midterm 2 Flashcards
Does sustainable farming need to Bec certified organic?
No!
What is sustainable agriculture?
A method of agriculture that focuses on raising animals humanely, maintain or improve environmental quality, steps taken to protect natural processes and biological diversity, economically viable, non renewable resources used efficiently
What is organic farming?
- subset of sustainable agriculture that species aspects of raising crops or animals:
- no growth enhancers allowed
- only approved chemical inputs, approved pesticides/feritlizers, no GMOs
What is agroecology?
- scientific field that considers that ecological and indigenous knowledge of an area and works to meet the needs of local people
What are the components of agroecokogy?
mimicking natural ecosystems on then farm
- minimises use of fertilizers and pesticides (saves money)
- increases biodiveristy
- creates a self regulating system
- leads to financial gain via polyculture
What is polyculture?
- growing multiple things at once, often with the addition of plant or animal components
- mixed polyculture may be most sustainable way for intensifying food production globally
What is the model for integrated farming systems (rice farm eg) ?
- rice planted in flooded plane - ducklings added to eat algae and provide fertilizers - fish added to do the same - azalea planted to provide Nitrogen, fish and ducks keep plant in check
What are some solutions to the overconsumption of water?
- plants use less than half of the water they are irrigated with
- drip watering is more efficient way to provoke plants with required water
- computerized moisture sensors can help control water application
What are some alternatives to inorganic fertilizers?
organic fertilizers!
- provides nutrients including micronutrients
- improves nutrient retention
- improves water holding capacity
- improves/maintains soil structure
What is the difference between organic and inorganic fertilizers?
- organic fertilizers feed the soil while inorganic fertilizers feed only the plants
What are some methods of pest management?
- integrated pest management
- crop rotation
- monitoring of populations
- biocontrol
- mechanical pest removal
- habitat complexity
-inter/strip cropping - transgenic crops
- use of chemicals
What is integrated pest management?
- multiple techniques used to decrease but no eliminate pests (some but not all), and minimizes but not removes use of pesiticides
1) identify true pests
2) set an action threshold, monitor pests
3) develop an action plan - control pest while minimizing chemical usage
Why is industrial agriculture harmful to soil?
- leads to deflation of soil (erosion and decline)
What are alternative to industrial agriculture?
- agricultural methods from around the world can promote soil health that don’t use synthetic fertilizers
- monitored not only through crop yield but also richness and diversity
What are all the natural forms of agriculture that protect soil?
Contour farming: planting along the land to prevent water and soil loss after it rains
reduced tillage: reducing disturbance of soil, reduce water needs (less evaporation) , reduce soil erosion, less fuel usage
terrace farming: farming flat in steps on hills to allow flooding for crops who need it, reduces soil erosion
crop rotation: moving crops every few years maintains soil fertility and reduces pests
strip cropping: planting in strips reduces pests (cannot move away from edge)
- trees have deep roots which help prevent erosion and birds, and help fertilize soil
cover crops: during off seasons plants like alfalfa planted to prevent soil erosion
What is the best plant type to use for cover crops?
- perennial plant because it grows year after year without replanting: reduces have machinery and soil compaction
- also deep roots allow for more access to water, reduced soil erosion, sequester carbon
What are the food miles?
- how far food must travel to get form area of production to consumer
What is a carbon footprint?
- amount of carbon released into atmosphere by a person, company, etc
how can we reduce carbon footprint when it comes to food miles?
- buy locally and support economy; fresher food
- sometimes too food from local industrial production still has greater remissions than sustainable from further away
Can sustainable agriculture feed the world?
2010 report says that mixed polyculture may be best sustainable way to do intensification of food production
What are the core messages of raising livestock?
- affluent affects diet -increases demand for meat products (US consumes more meat and dairy)
- industrial approaches to producing lots of affordable meat/produce have significant environment impacts and negative health impacts
- meat and dairy can help address world hinger and malnutrition but how best to raise animals topic for debate
Why is I = P x A x T related to affluence?
- richer can buy more meat and dairy
What are CAFOs?
- concentrated animal feeding operations
- a method to raise meat and dairy animals in confined areas maximizing # that can be rear in s mall area
Where does most meat and dairy bought from store come from?
Why are CAFOs a topic for debate?
- ethical concerns and environmental concerns
What are the shortcoming of the US Farm bill?
Farm bill is legislation that deals with many aspects of production and sale of farm raised commodity crops
- lax regulation of wastewater treatment
- provide subsidies making purchase of grain cheaper than it costs to produce
- current farm bill favours provisions for factory farming, including CAFOs
What is the feed conversion ratio?
- the proportion of edible food produced per unit of food input
- measures how quickly and efficiently a given animal conveys food into body mass
- CAFO cattle have a much higher (better) conversion rate than grass finished cattle
Why is the food fed to livestock a point of contention in terms of feeding people?
- about 70% of all US cropland used to grow feed for livestock
- that could be use to feed 5-10 x more people than the beef is used for
what is a water footprint?
- the amount of water that is consumed by a given group or activity
What is water primarily used for in CAFO beef production?
- irrigation for growing soybeans and corn for feed
- dealing with large amounts of manure produced
What is the carbon footprint?
- the amount of carbon released into atmosphere (and other greenhouse gas contributors) by person, groups, etc or activities
how high is CAFO carbon footprint? Why?
-18% of total global CO2 emissions from CAFOs
- cows release methane during digestion however large amount of CO2 released by growing crops like soybeans and corn for feed
Why are lagoons an environmental and potential health risk?
- ‘manure lagoon’ - over 160 gases emitted from CAFO waste
What are the pros of grass fed livestock?
- live entire lives on pasture farm
- healthier meat/milk
- healthier animals due to lots of movement and natural diets
- address many issues with feedlots (disease, ethics, etc)
What are the cons of grass fed livestock?
- do not gain weight nearly as quickly
- do not produce same volume as CAFOs
What are polyculture farms?
- rear different species of animals (or mix of animals and plants) together in some rotation
- may be more efficient use of land resources
- does not rely on high input of fossil fuels
What is the best solution to reduce environmental impacts of livestock ? Explain.
shift in diet
- regardless of method used to raise them cows still have highest environmental burden of any livestock
- pig, pork, chicken, eggs require much less water and land to grow food, and generate lower greenhouse gas emissions
- plant based food which are good sources of protein require even less land
Why does consumer choice matter?
-if CAFOs give way to grass fed farms and US farm bill then livestock will become decrease in numbers and increase in price
- people will choose to pay more or shift diet
- eating lower on the food chain may be key to a healthier andsitainale diet
What is the best way to make an affordable sustainable diet ?
- eating lower in the food chain!
What are the environmental impacts of specific diets?
US diets are greatest, then partial vegetarian, ovolacto and lacto vegetarian, and vegan (vegetarian best it uses more available land)
Why do humans need fish?
- humans consume more seafood than beef, chicken, and pork together
- provides 17% of global protein and is the primary source of protein for 3 billion people
- also fishing industry provides jobs for 200 million people
- 500 billion dollars in annual revenue from the fishing industry
In the documentary end of the line what where some underlying causes of the collapse of the fish stocks ?
- primary issue was overconsumption: too many boats, too few fish and fish don’t stand a chance against the technology - world’s boats could catch the world’s catch 4 times over
How much of the large fish stock depleted in the oceans?
- according to end of the line, 90% of large fish populations have been depleted
What are some methods of fishing that is harmful in end of the line?
- bottom trawling tears up the sea floor - destroys spewing areas making it harder for populations to recover
- kills sea stars, coral,
- large predators taken out leads to decline in biodiversity, and ecosystem services removed
What are some potential solutions to overfishing in end of the line doc?
- change consumption habits
- mpas have shown benefits: 12-14 billion to protect 30% of the ocean and would create 1 million jobs
campaign governments and politicians
What was the collapse of the Newfoundland fishery?
- for 400 hears Atlantic cod provided economic and cultural value to coastal Canada
- fishery collapsed and shut down in 1992 -
What is the tragedy of the commons?
Individuals exploit common resources for his or her own personal gain
- ocean is a commonly held open resource - “if I don’t use to someone else will’
- note: 35.5% of fisheries are exceeding their replacement rate
What does it mean to fish down the food chain?
- as higher trophic levels are depleted, people start going for the lower trophic levels
- graph demonstrates that over time trophic hunting levels decreased )Deplete upper levels so move down)
What are some hook and line fishing methods?
- pole and line
- long line
- trolling
What are some net based fishing methods?
Seine, bottom trawling, gill net
What is the best fishing practice? which is the least sustainable?
- best practice is the pole and line method: one hook, one fish
- worst is bottom trawling: severely damages sea floor and catches bycatch
What are EZZs?
exclusive economic zones: 200 nautical miles off of any coast gives that nations exclusive rights to the resources there including fish
- does not prevent overfishing (could if managed properly but isn’t )
What are MPAs?
- marine protected areas: ocean zones that certain action is prohibited - sometimes only applies to specific things like a certain species or discrete portion of the habitat like historical artefacts or spawning ground
What can be done about unsustainable fisheries?
- gear substitution: bottom trawlers and bottom longline
- gear modifications: turtle excluding device, or tori lines b
how much of the fish harvested today is harvested will illegal gear?
> 30% of fish today is harvested with illegal gear
Why do we care about coral reefs ?
- ecological goods and services renewable resources, non-renewable resources, abiotic and biotic services, information, physical and cultural aesthetics
What are some services that make coral reefs so valuable? What are they valued at?
- very high ecosystem value
- water purification, medicinal value (antibiotics and anticancer drugs), recreation, support fisheries, food and space for aquatic organisms
How are parrotfish and coral related?
- parrotfish eat coral and produce the white sand found on white sand beaches
Are all services of the coral reef from the coral themselves?
Some come directly form the coral, some come for the ecosystem it creates /supports
Describe the relationship between coral and zooxanthellae
coral polyps are found within their hard calcium carbonate exoskeleton and they cannot photosynthesize on their own to create energy - zooxanthellae are a photosynthesis algae that produces sugars for the coral - they live in the epidermal layer of the coral -
What do coral eat?
- zooxanthalle provide sugar for them from photosynthesis, but they also have tentacles that they elongate at night to catch organisms that they pierce and stun
How do coral create their exoskeleton?
- exoskeleton provides protection for coral - they catch minerals from the water and form calcium carbonate, which they can retract their tentacle into to keep them safe
- it builds the calcium carbonate skeleton in the area where they have created space
-NOTE : coral are built on a ‘bed of bones’ - long dead coral is what new coral is built upon :)
