Environmental science after midterm 2 Flashcards
(155 cards)
1
Q
Does sustainable farming need to Bec certified organic?
A
No!
2
Q
What is sustainable agriculture?
A
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
3
Q
What is organic farming?
A
- 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
4
Q
What is agroecology?
A
- scientific field that considers that ecological and indigenous knowledge of an area and works to meet the needs of local people
5
Q
What are the components of agroecokogy?
A
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
6
Q
What is polyculture?
A
- 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
7
Q
What is the model for integrated farming systems (rice farm eg) ?
A
- 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
8
Q
What are some solutions to the overconsumption of water?
A
- 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
9
Q
What are some alternatives to inorganic fertilizers?
A
organic fertilizers!
- provides nutrients including micronutrients
- improves nutrient retention
- improves water holding capacity
- improves/maintains soil structure
10
Q
What is the difference between organic and inorganic fertilizers?
A
- organic fertilizers feed the soil while inorganic fertilizers feed only the plants
11
Q
What are some methods of pest management?
A
- integrated pest management
- crop rotation
- monitoring of populations
- biocontrol
- mechanical pest removal
- habitat complexity
-inter/strip cropping - transgenic crops
- use of chemicals
12
Q
What is integrated pest management?
A
- 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
13
Q
Why is industrial agriculture harmful to soil?
A
- leads to deflation of soil (erosion and decline)
14
Q
What are alternative to industrial agriculture?
A
- 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
15
Q
What are all the natural forms of agriculture that protect soil?
A
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
16
Q
What is the best plant type to use for cover crops?
A
- 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
17
Q
What are the food miles?
A
- how far food must travel to get form area of production to consumer
18
Q
What is a carbon footprint?
A
- amount of carbon released into atmosphere by a person, company, etc
19
Q
how can we reduce carbon footprint when it comes to food miles?
A
- buy locally and support economy; fresher food
- sometimes too food from local industrial production still has greater remissions than sustainable from further away
20
Q
Can sustainable agriculture feed the world?
A
2010 report says that mixed polyculture may be best sustainable way to do intensification of food production
21
Q
What are the core messages of raising livestock?
A
- 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
22
Q
Why is I = P x A x T related to affluence?
A
- richer can buy more meat and dairy
23
Q
What are CAFOs?
A
- concentrated animal feeding operations
- a method to raise meat and dairy animals in confined areas maximizing # that can be rear in s mall area
24
Q
Where does most meat and dairy bought from store come from?
A
25
Why are CAFOs a topic for debate?
- ethical concerns and environmental concerns
26
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
27
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
28
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
29
what is a water footprint?
- the amount of water that is consumed by a given group or activity
30
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
31
What is the carbon footprint?
- the amount of carbon released into atmosphere (and other greenhouse gas contributors) by person, groups, etc or activities
32
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
33
Why are lagoons an environmental and potential health risk?
- 'manure lagoon' - over 160 gases emitted from CAFO waste
34
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)
35
What are the cons of grass fed livestock?
- do not gain weight nearly as quickly
- do not produce same volume as CAFOs
36
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
37
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
38
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
39
What is the best way to make an affordable sustainable diet ?
- eating lower in the food chain!
40
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)
41
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
42
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
43
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
44
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
45
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
46
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 -
47
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
48
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)
49
What are some hook and line fishing methods?
- pole and line
- long line
- trolling
50
What are some net based fishing methods?
Seine, bottom trawling, gill net
51
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
52
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 )
53
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
54
What can be done about unsustainable fisheries?
- gear substitution: bottom trawlers and bottom longline
- gear modifications: turtle excluding device, or tori lines b
55
how much of the fish harvested today is harvested will illegal gear?
>30% of fish today is harvested with illegal gear
56
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
57
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
58
How are parrotfish and coral related?
- parrotfish eat coral and produce the white sand found on white sand beaches
59
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
60
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 -
61
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
62
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 :)
63
What organisms do corals abiotic conditions need to satisfy? Are all corals conditions the same?
- conditions must accommodate for both the coral and symbiont zooxanthellae
- cold water coral (that live deep in the ocean) do not have symbiont algae, and require different conditions
64
What are the temperature requirements of coral?
- tropical coral prefer warmer waters (within 30 degrees of the equator)
- they also do not like fluctuating temperatures
65
Where are most coral found relative to continents?
- most are found on the eastern side of continents where warm western boundary currents are
- coral on the western sides are generally less extensive and more fragmented (due to upwelling)
66
Why is coral less extensive on the western sides of continents? Does this process occur often?
more upwelling occurs here
- upwelling is when deep, nutrient rich waters come up from the ocean bottom - water is too cold for tropical coral
- upwelling occurs in <1% of oceans but forms very productive areas
67
What salinity do coral prefer?
coral do not have very broad salinity tolerance
Tropical coral prefer salinity of 35-36ppt - exception in the persona gold where temperatures are high and salinity is high but they have adapted to those conditions and they are consistent
- salinity is higher in areas of greater evaporation (ie: warm waters)
68
Where does salt come from? What determines 'saltiness' of the ocean?
- salt comes from minerals and weathered rocks add minerals to the water
- saltiness of the ocean based on the rate of evaporation ; higher evaporation = greater salinity (in warmer areas) .
69
what kind of coral may be an exception to the 30 degrees rule?
- deep water coral
70
Are coral osmoconformers or osmoregulators ?
Coral are osmoconformers = their internal salinity matches that of their surroundings
71
Would we expect to find coral near river mouths?
no! They don't like freshwater
72
What is an exception to salinity rules of coral?
- coral reef in the Persian gulf lives in warmer, saltier water - evaporation increases here so water increases in salinity BUT they are adapted to these conditions and the conditions do not vary - coral do not like change!
73
What depth conditions do coral prefer?
- coral need light so they're found within 30-50 m
- if the water is very clear it may get up to 60-75m
- cold water coral do not need light so less dependent - but coral in a traditional sense must have light accessibility
74
How does light regulate coral distribution?
- light impacts depth and geography
- impact photosynthesis and calcification rates
75
How is light measured?
using the PAR (photosynthetically active radiation) is measured on the electromagnetic spectrum
76
Is light penetration greater in coastal or deep water?
- coastal waters are less till and have more sedimentation blocking light
77
Describe nutrient conditions of the coral reef
- coral reefs are oligotrophic - low nutrient content
- reefs: N= 0.5 mewm, P = 0.2 mewm
- deeper water N = 10-40 mewm, P = 1-4 mewm
78
What is oligotrophic and eutrophic water?
Oligotrophic - nutrient poor
Eutrophic - nutrient rich
79
What do coral eat?
Sugars from zooxanthellae, and have tentacles that pierce and stun food at night
80
What is the greatest threat to coral reefs ?
- coral bleaching: occurs when zooxanthellae leave the coral polyps and the coral are exposed - do not die, but if thermal stress continues they will due and be covered in filamentous algae
81
Do coral die when zooxanthallae leave?
- depends on the cause of the bleaching events: intensity and length of stress
- if water cools down they can recover
82
Why is the future of coral a concern?
bleaching events are increasing in size and periodicity
83
What environmental conditions lead to mass bleaching events?
- thermal stress and bright sunny still weather
84
How can we address coral bleaching?
Reduce carbon footprint and mitigate climate change
85
How does cold water coral differ form tropical coral?
- cold water coral is deeper, does not require photosynthesizers so it is in areas of higher nutrients
86
What is the result of the harvest from integrated farming of rice crops?
- duck eggs, fish, duck, and rice yield!
87
how does industrial agriculture impact soil fertility? How is this addressed?
- industrial agriculture reduces soil fertility - cultural, non industrial agricultural methods from around the world are used to maintain fertility and boost crop production without the use of synthetic fertilizers
88
How is success in non-industrial agriculture methods measured?
- in crop yields as well as richness and diversity of the entire farm habitat
89
What is a viable method of sustainable farming?
polyculture that integrates multiple species
90
What are the two main things that sustainable agriculture must do?
- maintain or improve quality of land
- feed people
91
What does mimicking natural ecosystems benefit?
both the people and the land
- using indigenous knowledge can match the farm to the local community
92
Why is meat production helpful to the world?
- can address global hunger and malnutrition, but how best to raise them is a topic for debate
93
Why is industrial meat production helpful? Why might it be harmful?
- industrial production of livestock helps make meat and dairy prices affordable, but has negative health and environmental impacts
94
Q: How does global food consumption tend to change with increasing per capita wealth?
- more meat and dairy are consumed
95
How much of US crop land is used for feed production?
70% of US cropland is used for livestock
- this could feed 5-10x more people than the beef it is used to produce
96
What is most water in livestock production used for?
- irrigation : growing the crops for animal feed
- and managing the large amounts of manure produced
97
Where do most emissions from livestock production come from?
- in cows, though they release methane, most of the greenhouse gases comes from producing the corn and soybeans they are fed
98
What is a lagoon? Why are they a concern?
- a lagoon is an area where manure is stored
- CAFOs create huge amounts of waste; lagoons prove to be environmental and health risks as they release over 160 gases
99
What are polyculture farms?
- a method of raising multiple things at once, often with the addition of plants and animals
- may be a more efficient way to use land resources
- less reliant on fossil fuels
100
Why are polyculture farms less reliant on fossil fuels than other farming methods?
- its a self reliant, integrated farming method !
101
What is the best way to reduce the environmental impact of livestock?
a shift in diet
- beef production has the highest environmental burden of any livestock
102
How might changing US agricultural policies impact sustainable diet culture?
- is US agricultural policies changes and CAFOs gave way to grass fed farms, cattle meat production would greatly decreased and become more expensive
- people would be forced to spend more money for the same amount of meat, or change their diets
- eating lower on the food chain may be the most effective way to promote a sustainable diet
103
Why might eating lower on the food chain promote a more sustainable diet?
- the food used to feed livestock could feed 5-10 x more people than the beef it is used to produce
- livestock accounts for 18% of greenhouse gas emission
- other forms of livestock (not beef) use less land and water and release less emissions
- plant based alternatives used EVEN LESS water and land, and is a far more sustainable way to use the land for food production
104
What is sea water made of?
- minerals and gases like calcium, potassium ,sodium, magnesium, chlorine etc
105
Where do the ions and gases that make up the atmosphere originate from?
- volcanic activity, atmospheric gases, biological processes, weathering and erosion
106
What makes up the atmosphere?
N2- 78% of the atmopshere
O2 - 21%
CO2- 0.038%
others - methane, chlorofluorocarbons, water vapour, nitrous oxides, CCl4, O3
107
How does carbon get into the atmosphere?
- burning of fossil fuels, geological processes, and net deforestation (take down more than is grown)
108
Where do the majority of Canada's GHG emissions come from?
- mining, transportation, forest fires
The largest portion of the graph was energy from stationary combustion sources
109
Describe the increase of CO2 from the 1700s/1800s
- 1700s was when Britain's Industrial Revolution began, more CO2 recorded in 1875- around the time of NAs industrial revolution
- so between 1800-1900 CO2 levels began to rise (Mauna Loa observatory)
110
How does the ocean impact atmospheric CO2?
- 25-30% of atmospheric CO2 is absorbed by the ocean
111
how do we measure pH? What is the pH of sea water? Freshwater?
- pH scale: 0-14
- sea water is historically 8.1-8.3
- freshwater is 7
112
Describe how CO2 gets absorbed into the ocean
- CO2 (g) --> Co2 (Aq) - combined with water to form H2CO3 (carbonic acid) --> turns into bicarbonate and hydrogen ions --> turns into carbon and hydrogen
113
How does ocean acidification occur?
- increased CO2 in the atmosphere means increased hydrogen ions released into the water
- decreased the pH of the ocean
114
How has the pH of the ocean changed?
- preindustrial pH : 8.2
- predicted pH by 2100: 7.7
115
How do coral make their shell?
- their shell is made from calcium carbonate, called aragonite crystals
- Calcium in the ocean combines with carbonate ions to form calcium carbonate
116
Is calcium limiting in the ocean?
- calcium is abundant in the ocean, but carbonate can change depending on dissolved levels of CO2
117
How does ocean acidification impact the formation of calcium carbonate shells?
- increased CO2 leads to increased dissolved H+ ions in the water
- H+ binds to CO3- which is used for shells
- H+ also causes shells to dissolve into Ca+ and HCO3-
--> so increased hydrogen leads to dissolving of shells and interferes with their formation
118
What might we expect to occur to corals as oceans become more acidified?
- decrease in linear growth rates
- increased storm drainage and bioerosion (dissolution is impacted by size, texture, morphology)
- the energy required to make shells easy limit other biological processes (like reproduction)
119
how can predictions about acidification on coral be tested ?
- lab and field experiments, look to natural environments, study coral biochemistry
120
What did the experiment on coral acidification reveal?
- the area with higher levels of CO2 -closer to vents - had sparse coral, and dominated by large amounts of sponges and fleshy seaweed
121
Describe the process of coral calcification
- calicoblastic epithelium: where the calcification takes place
- requires energy from the coral
- coral controls the pH of the calcifying fluid to make it optimal for the formation of calcium carbonate
122
What are the impacts of ocean acidification on phytoplankton?
- shifting pH shifts availability of nutrients
- Decreasing pH leads to decreased nitrogen and phytoplankton communities change which alters the functioning of the rest of ecosystem through altering food webs
123
What are the ocean acidification impacts on other marine calcifers?
- other marine calcifers: organisms who form a calcium based exoskeleton or shell
- acidification eats away at pre existing calcium based materials
- interferes with chemical reactions that produce those calcium based materials
- organisms like pteropods have no layer of tissue on their exoskeleton and are exposed to the ocean water
124
Describe the pattern of emissions from the 1900s
- in the 1900s the primary contributor to global emissions was coal - in the 1920s another major contributor introduced: oil - 1950s the 3rd contributor was natural gas - and co2 emissions rose rapidly after 1950s
- since 1940's natural gas emissions steadily increasing
- coal has been decreasing significantly since 2000
125
What does the future of the ocean look like if CO2 levels continue to rise as they are?
- atmospheric CO2 will continue to rise, and ocean pH will continue to fall - has implications for oceans as a natural resource used for recreation, commerce, and food
126
What are some solutions to protecting marine areas?
- the concept of MPAs expanding in the last 20 years
- seeks to:
1 ) complement conventional fisheries management techniques
2) protect representative habitats or particularly diverse areas
127
What is the UN's goal on ocean protection? What was and is Canada's goal?
UN seeks to protect 30% of the oceans by 2030
- Canada met the 10% protect by 2020 goal, now 25 by 25, and 30 by 30
128
What are some drawbacks of MPAs?
- regardless of MPAs, illegal and unreported fishing still occurs - >30% of annual catch comes from illegal gear
- MPAs also tend to only protect certain things like one kind of fish, or a spawning ground or historical artefact
129
What percentage of fisheries currently exceed their replacement rate?
35.5% of fisheries exceed their replacement rate
130
Which form of fishing has the most bycatch? Which has the least?
- bottom trawling has the most bycatch - destroys the seabed, kill millions of coral, algae, sponges, etc - and prevents recovery by destroying spawning grounds
- hook and line has the least by catch: one hook, one fish
131
What are some modifications that can be done about unsustainable fishing methods?
- gear substitution: bottom trawlers and bottom long line
- gear modifications: tori line - prevents birds - and turtle excluding devices
132
What is an RAS? What conditions do they provide? What do they do with waste
- Recirculating aquaculture system; a system that raises fish in tanks and filters and recycle the water
- conditions: pH, temperature, and salinity are kept optimal
- food; reduced food intake due to optimal conditions and lack of activity
- breeding; conditions and hormones introduced to stimulate breeding
- solid waste is turned into CH4 for fuel for the facility
- ammonia (toxic) is turned into N2 (non-toxic)
133
What does oligotrophic and eutrophic mean?
- eutrophic : too many. nutrients in the water
- oligotrophic: not enough nutrients - where coral are found, rely on photosynthesizers to get nutrients
134
Why are corals not generally found on the western side of continents?
- there is too much upwelling - cold water, not ideal for Coral - the coral that is there is sparse
135
What are the benefits of using organic fertilizers?
- improves soil quality
- improves water holding capacity
- improves nutrient retention
- improves nutrient availability, including micronutrients
136
How is crop productivity measured in traditional non-industrial farming methods?
- measured in crop yield, richness, and diversity
137
How does industrial farming impact soil?
- leads to a decline in soil fertility; instead turn to the non industrial cultural farming methods
138
Can sustainable agriculture feed the world?
- mixed polyculture holds the most promise for sustainable intensification of food production
→ A combination of methods targeted for the local community will probably work best
139
Where does most meat in the grocery store come from?
- industrial scale operations
140
What are the forms of diets? Which is the most sustainable?
- US diet - partial vegetarian (60% omnivore, 40% vegetarian) - ovalacto vegetarain - lacto vegetarian (milk only) - vegan
- lacto vegetarian can actually feed the most people because it maximizes use of land
141
Globally do we consumer more fish or meat?
- globally we consumer more fish than beef, chicken, and pork combined
- accounts for 17% of the world's protein intake and more than 2 billion people rely on it as a primary source of protein
= 200 million people rely on fishing for their livelihoods
142
Which industrial fishing method is more sustainable?
- hook and line because it does not destroy the habitat
143
why is aquaculture a fast growing industry?
- globally fast growing, including Canada, in response to decline in global fish stocks
144
What are some ecosystem services associated with coral reefs?
- purify water, support commercial fisheries, recreation, food/habitat for fish, sources of medicine
145
Can coral regulate their own salinity?
- no! they are osmoconfomers so their internal salinity reflects external salinity levels
146
What makes the ocean salty?
- salt comes from rocks on land / erosion
- evaporation also contribute ; when evaporation exceeds transpiration it becomes saltier
- coral does not like varying salinity and needs 35-36 ppt
147
Why won't coral be found around river mouths?
- freshwater (and too cold)
148
What does higher CO2 in the atmosphere mean for earth's systems?
- terrestrial plants will absorb 25% of that
- oceans absorb 25-30% of atmospheric CO2 - acidification
- the remaining leads to global warming
149
How much of plan oil comes from Malaysia and Sumatra?
95% of palm oil comes from Malaysia and Sumatra - leads the world in deforestation rates!
- 1/2 of all US household food and products contain palm oil - demand in the US has increased 6 fold since 2000
150
How many species exist?
we don't know - 1.5 million identified, 3-11 million estimated , >150billion with bacteria
151
What are ecosystem services?
encompasses cultural benefits, regulation and support, and provisioning
152
How much mercury is allowed to be eaten?
- eat up to 6 ounces (one meal) of fish a week
or
12 ounces (2 meals) of fish low in mercury (canned tuna, salmon)
- white tuna has more mercury than canned tuna so eat only 6 ounces
153
Which two fish have the largest amounts of mercury?
large mouth bass and spotted bass
154
How much of land is covered in forests?
25%
155
