AP Environmental Science Course Review Part 1
AP Environmental Science Course Review Part 1
80 mc questions in 90 minutes - 60% of exam score
3 FRQ in 70 minutes - 40% of exam score
Question 1: design an investigation
Question 2: analyze environmental problem + propose a solution
Question 3: analyze environmental problem + propose solution doing calculations
hypothesis and/or predictions
identify the independent variable - what treatments will you apply
identify the dependent variable - what will you measure
identify several variables to be controlled (very important)
describe the materials you would use to conduct the experiment. Be specific!
describe what you will actually do. Give a specific list of steps you’d follow.
describe how you will actually take and record data
describe how the data will be graphed and analyzed
state how you will draw a conclusion (claim-evidence-reasoning with comparison of outside sources)
Things to know….. Million= 106 Billion= 109 Mega= 106 (ex: 1,000,000 BTU/ 1 MBTU) Kilo= 103 (ex: 1000 watts/ 1 kW) Half Life 1 1/2 1/4 1/8 1/16 1/32 1/64 | Population Stuff…. Approximate population for: The world: 7.5 billion China: 1.3 billion India: 1.3 billion The US: 325 million Per Capita = Per Person |
Percent Percent is part divided by the whole times 100! Primary Productivity Gross primary productivity - respiration = net primary productivity | Population Math Population Density= Number of individuals/ area Growth Rate is a % B-D/ population size * 100 Rule of 70 DT = 70/ GR |
Percent Change | ENERGY KWh= kilowatts * hours Efficiency can be solved using ratios |
ALWAYS! EVERYTIME! SHOW YOUR WORK!
|
1963 (revised several times since) Clean Air Act (CAA): Includes provisions for:
Sulfur oxides, carbon monoxide, particulate material, volatile organic compounds, nitrogen oxides, ozone, lead
Providing resources to study air in order to inquest about the issue of atmospheric pollutants.
Setting enforceable regulations to limit emissions from stationary and mobile sources
Developing programs to monitor and reduce acid deposition
Establishing a program to phase out the use of chemicals that deplete stratospheric O³
Establishing a cap and trade (a system in which maximum allowable emissions are set for each industry; businesses that reduce their emissions to below the standards are awarded credits which they can sell to other businesses within their industry, creating economic incentive for reducing emissions).
1970 National Environmental Policy Act (NEPA): One of the first pieces of environmental legislation in the United States, NEPA was written to promote the idea of sustainability.
Environmental Impact Statement (EIS): Any major federal agency must submit an EIS for any activity that may have a harmful impact on the environment.
1970 Environmental Protection Agency (EPA): Formed under the Nixon Administration with the primary purpose of protecting human health and the environment and enforce environmental standards under a variety of state and local environmental laws.
1972 (revised several times since) Clean Water Act (CWA): A response to the 1969 Cuyahoga River catching fire in Cleveland, Ohio. Its mission is to restore and maintain the chemical, physical, and biological integrity of Americaʼs waterways and make them “fishable and swimmable.” Provisions intended to reduce and prevent point and nonpoint sources of water pollution, although there are no provisions regarding groundwater protection.
1973 Endangered Species Act (ESA): A far-reaching act that provides protection for any species that is determined to be threatened with extinction. Provisions include strict enforcement of habitat protection, a ban on any activity which disturbs or endangers the life of a listed species, and a ban on the import or export of any individual organisms or product derived from an endangered species.
1973 Convention on International Trade in Endangered Species of Wild Flora and Fauna (CITES): A multilateral treaty ensuring that international trade in specimens of wild animals and plants does not threaten the survival of the species in the wild and accords varying degrees of protection for more than 33,000 species.
1974 Safe Drinking Water Act (SDWA): Focuses on maintaining the purity of any water source that may potentially be used as drinking water, including both surface and groundwater.
1976 Resource Conservation and Recovery Act (RCRA): Also called the “Cradle-to-Grave Act,” sets specific regulations concerning the manufacture, transport, storage, use, and disposal of a host of hazardous chemicals. Its major provision requires extensive documentation at every step to ensure the hazardous wastes are disposed of properly.
1980 Comprehensive Environmental Response, Compensation, and Reliability Act (CERCLA): Also called the Superfund Act, established to handle industrial contamination in sites where no direct individual or party could be help responsible. Imposed a tax on the chemical and petroleum industries and authorized the federal government to respond to the release of hazardous substances. Also created a trust fund for cleaning hazardous waste sites when no responsible party could be identified.
1987 Montreal Protocol: A global effort and one of the greatest environmental success stories to date. Provisions include requiring participating nations to phase out the use of ozone-depleting chemicals (specifically CFCs) in favor of less harmful alternatives.
1997 Kyoto Protocol: Developed at a world summit to address measures for reducing greenhouse gas emissions. No real progress was made; when the US announced it would not sign the protocol the whole movement lost support
1938 Delaney Clause of Food, Drug, and Cosmetic Act: chemical additives “found to induce cancer in man” or in animals could NOT be approved for use in foods by the FDA
1.1 Introduction to Ecosystems
Presence of a species may be influenced by:
Fundamental niche: range of abiotic factors it can tolerate
Ability to disperse
Interactions with other species
Competition, predation, mutualism, commensalism
Competition: the struggle of individuals to obtain a limiting resource
Competitive exclusion principle: two species competing for the same limiting resource cannot coexist (CAN LEAD TO RESOURCE PARTITIONING)
The process of partitioning reduces competition between 2 species
Temporal: species use same resource at different time
Spatial: species reduce competition by using different habitats
Morphological: evolution of different body shapes or size
Predation: the use of one species as a resource by another species
True predators: kill their prey
Herbivores: consume plants as prey
Parasites: live on or in the organism they consume
Typically only consume part of their host, single parasites rarely cause death
Parasites that cause disease in the hosts are pathogens
Parasitoids: lay eggs inside other organisms
When hatch, larva slowly consume the host from inside out, causing the hosts death
Mutualism: interspecific interaction where both species benefit (acacia tree and ants)
Commensalism: ons species benefits but the other is neither harmed nor helped (clownfish /anemone)
Parasitic: one benefits and the other organism is harmed
1.2 Terrestrial Biomes
Tundra Biome
Cold & treeless, with low growing vegetation
Arctic tundra – N most regions of N. Hemisphere
Very short growing season (4 months during summer)
Upper layer of soil thaws, creating pools of standing water- ideal habitat for mosquitoes
Permafrost- underlying subsoil, impermeable, permanently frozen- prevents deep rooted plants
Little precipitation
Plants: lichen, moss, woody shrubs
Soil: slow rate of decomposition resulting in accumulation of organic matter in the soil over time with relatively low levels of soil nutrients
Boreal Forest (Taiga) Biome
Coniferous (cone bearing) evergreen trees (Ex: Pine and Spruce)
Evergreen- green year round
Europe, Russia, N. America
Plant growth constrained by temperature
Decomposition a slow process (cold) & low nutrient content in waxy needles – thick layer of organic material but soil low in nutrients
Some deciduous trees- lose leaves (Ex: Birch, Maple, Aspen)
Extensively logged for pulp, paper, and building materials
Temperate Rainforest Biome
Mid-latitude- west coast of N. America from Northern CA to Alaska
Ocean water is source of water vapor
Mild summers and winters
12 month growing season (almost)
Coniferous trees most common (Ex: Spruce, Cedar, Fir, Hemlock, Redwoods)
Redwoods (Sequoia sempervirens)
Ferns and mosses (can live in nutrient poor soil) are found under trees
Nutrients released are uptaken by trees or leached out by abundant rain
Temperate Seasonal Forest Biome
Deciduous trees
Warm summer & cold winter
Eastern USA, Japan, Europe, China
Warm summers favor rapid decomposition
Soils have more nutrients because deciduous leaves decompose faster
Historically one of first biomes to be converted to agriculture
Woodland/Shrubland Biome
Hot/dry summers and mild/rainy winters
Southern CA = chaparral
Wildfires
Fire dependent plant species
Drought resistant shrubs (Ex: yucca, scrub oak, sagebrush)
Soil low in nutrients from winter rains
Agriculture: grazing animals and deep rooted crops like grapes to make wine
Temperate Grassland
Cold/harsh winters & hot/humid winters
Great Plains of N. America = prairies
S. America = pampas
Central Asia/E. Europe = steppes
Fires
Plants: grasses & nonwoody flowering plants
Long growing season & rapid decomposition – nutrient rich soil
98% of tall grassland in USA has been converted to agriculture
Short grass prairie is converted to growing wheat
and grazing cattle
Tropical Rainforest
Warm/wet @ 20° N/S latitude
ITCZ
High productivity, extremely high decomposition rate
Soils lose nutrients quickly
Slash and burn agriculture
More biodiversity per hectare than any other terrestrial biome
Plant: epiphytes (hold small pools of water to support an aquatic ecosystem)
Tropical Seasonal Forest/Savanna
Lion King!
Warm temperature & wet season/dry season
Dense stands of shrubs and trees
Grazing & fire discourage growth of smaller woody plants
Warm temperature promotes decomposition but low rain prevents plants from using soil nutrients
Subtropical Desert
Hot/extremely dry
Plant adaptations: small or nonexistent leaves modified into spines, thick waxy outer layer, most photosynthesis occurs in plant stem
Less than 10 inches of rain/year
1.3 Aquatic Biomes
Freshwater biomes: streams, rivers, ponds, lakes that are used for drinking water
Marine biomes: oceans, coral reefs, marshlands, and estuaries
Algae in marine biomes supply a large portion of the Earth’s O2 and take in CO2 from the atmosphere
The global distribution of nonmineral marine natural resources such as dif fish varies because of the combination of salinity, depth, turbidity, nutrient availability, and temperature
Streams: the faster a stream flows, the greater the amount of dissolved oxygen in it
Rivers: water moves slower in a river and debri settles on the bottom
Usually have more nutrients and less dissolved oxygen
Littoral zone: shallow area of soil and water near the shore where algae/emergent plants grow
Limnetic zone: open water, where rooted plants can no longer survive
Phytoplankton are the only photosynthetic organisms, extends to as deep as sunlight can penetrate
Profundal zone: zone where sunlight cannot penetrate so producers cannot survive
Benthic zone: muddy bottom of a lake or pond beneath the limnetic or profundal zone
Oligotrophic: low levels of organic matter
Tend to be deep and clear, oxygen rich bottom supports cold water fish like trout, phosphorus is limiting
Mesotrophic: more organic matter
Oxygen level in lake bottom is low
Eutrophic: high levels of organic matter
Abundant plant growth, poor clarity, oxygen poor bottoms
Freshwater Wetlands
Aquatic biomes that are submerged or saturated by water for at least part of each year, but shallow enough to support emergent vegetation.
These include swamps, marshes, and bogs.
Swamps: wetlands with emergent trees
Marshes: wetlands that contain primarily non woody vegetation, like cattails and sedges
Bogs: acidic wetlands that typically contain sphagnum moss and spruce trees
Marine Biomes: salt marshes, mangrove swamps, intertidal zones, coral reefs, open ocean
Mangrove Swamp
Occur along tropical and subtropical coasts
Tree roots submerged in water
Trees are salt tolerant
Help protect coast from erosion & storm damage!!!
Falling leaves produce nutrient rich environment
Provide sheltered habitat for fish and shellfish
Estuaries
Area where a river meets an ocean
Mix of salt and freshwater
Located near coastlines, border land
Extremely fertile
Nutrient levels are higher than both salt and freshwater
Salt Marsh
Found along the coast in temperate climates and contain non woody emergent vegetation.
The salt marsh is one of the most productive biomes in the world.
Naturally occurring wetlands wound within the intertidal zone
Ecosystem service: absorb storm surge
Intertidal Zone
Band of coastline the exists between high and low tide
Range from steep and rocky to broad and sloping mudflats
Stable environment when submerged during high tide
Harsh conditions during low tide when organisms are exposed to direct sunlight, high temperatures and desiccation
EX: barnacles, sponges, algae, mussels, crabs, sea star
Coral Reef
Found: warm shallow waters beyond shoreline
Earth’s most diverse marine biome
Coral- tiny animals the secrete layer of limestone (calcium carbonate) to form external skeleton
Animal lives inside this tiny skeleton with tentacles that draw in plankton and detritus
Coral lives in water that is relatively poor in nutrients and food
Therefore have a relationship with single celled algae that live in the tissue of corals called zooxanthella
Algae use CO2 captured during photosynthesis to produce sugar and nutrients… then release this to the coral animal
Coral gains energy from sugar… and the algae gets CO2, nutrients and a safe place to live
Coral bleaching
When algae in coral die- without algae the coral dies
Cause: turbidity, ocean temperature increase, pollution, tourism, ocean
Open Ocean
How deep the light penetrates depends on the amount of sediment & algae suspended in the water
Will not exceed 200 m (approximately 650 feet)
Is divided into zones
Photic- light
Aphotic- no light
Benthic- bottom
Photic zone: relatively shallow part of the ocean above the drop-off of the continental shelf
Enough sunlight for photosynthesis, approximately 200 m/660 ft in depth
Intertidal zone: area where the ocean meets the land between high and low tides
Pelagic zone: sometimes called the open zone
Salinity, depth, temperature, turbidity (loss of transparency), nutrient availability in the ocean varies
1.4 The Carbon Cycle
Carbon has 2 stages: the fast stage associated with living organisms
Slow stage: associated with dead organisms (fossil carbons)
1. When plants carry out photosynthesis the use CO2 from the atmosphere
Plats release some of the CO2 back into the atmosphere with cellular respiration but keeps most of it within their plant tissues
2. The plant will die or be eaten by another organism that will die; the dead matter contains carbon will be processed by decomposers and exist in soil so more plants can use it
Decomposition: microbes, bacteria, fungi break down organic matter and release CO2 (aerobic decomp), CH4 (anaerobic decomp)
1. Carbon exchange occurs in the ocean: the ocean absorbs some CO2 form the atmosphere and release CO2 back into the atmosphere
Sedimentation: the CO2 combines with calcium ions in the water to form calcium carbonate that sinks to the bottom of the ocean and accumulated
Dissolved CO2: CO2 DISSOLVES into the ocean from the atmosphere and moves between atmosphere and ocean via direct exchange
Ocean is the largest carbon sink
Sequestration: storage of carbon in biomass, sediments, limestone, fossil fuels
1.5 The Nitrogen Cycle
Nitrogen, phosphorus, potassium, calcium, magnesium, and sulfur
Most reservoirs in which nitrogen compounds occur hold them for relatively short periods of time
Atmosphere is the major reservoir of nitrogen (78% of the air on Earth)
nitrogen/phosphorus: often a limiting nutrient
Limiting nutrient: often required for the growth of the organisms but available in a lower quality than other nutrients
Nitrogen (N2 in air is useless to organisms and must be fixed into usable form: nitrate, nitrite, ammonia)
Nitrogen Fixation: N2>NO3
Bacteria in roots of legume
Usable form for plants (nitrite)
When animals eat these plants usable nitrogen is acquired (assimilation)
Ammonification: when plant/animal dies or excrete waste, microorganisms covert their N compounds to ammonia
Nitrification: most plants cant use ammonia so they convert it tinto nitrate (NO3)
One group of soil bacteria change ammonia to nitrites
Another group of bacteria convert nitrites to nitrates
Denitrification: other bacteria convert ammonia, nitrate, and nitrite back into N2 - returning into the atmosphere
Assimilation: producers take up N in form of ammonia, ammonium, nitrate, nitrite, and incorporate it into their tissues
Natural way to fix nitrogen: lightning
2 plants that fix nitrogen: legumes, rye (grass)
Nitrate is a limiting nutrient essential to plant growth- burning soil vegetation increases nitrate levels , so testing would would allow the scientist to measure how much the levels are increasing by burning to help determine the impact of wildfires on plant growth and succession
1.6 The Phosphorus Cycle
No atmospheric component (is a limiting factor)
Limitation imposed on return from the oceans to land to make phosphorus scarce in aquatic and many terrestrial ecosystems ( limiting factor)
Found as phosphate (PO4 3): mineralization of organic phosphorus back into inorganic phosphorus >slow cycle in rocks
N & P runoff and algal bloom= hypoxic
Major reservoirs of phosphorus: rock and sediment that contain phosphorus-bearing minerals
1.7 The Hydrologic Cycle
Powered by the sun> movement of water in its various solid, liquid, and gaseous phases between sources/sinks
Oceans are the primary reservoir of water at the Earth’s surface, with ice caps/groundwater as smaller reservoirs
1. Heat from sun causes water to turn into water vapor>rise into atmosphere
Water from ground>air by either evaporating from body of water or ground or plants can release water through transpiration
2. Once in atmosphere, comes down to Earth in form of precipitation
Can result in surface runoff (water slides from the and back into body of water); percolation (water will be absorbed by the ground and become part of groundwater stores); plants uptake to use for photosynthesis
1.8 Primary Productivity
Primary productivity: rate at which solar energy is converted into organic compounds via photosynthesis over a unit of time
Gross primary productivity (GPP): total rate of photosynthesis in a given area
Net primary productivity (NPP): rate of energy storage by photosynthesizers in a given area after subtracting the energy lost to respiration
Measured in units of energy per unit area per time (ex. kcal/m^2/yr)
Producers capture about 1% of available energy via photosynthesis> GPP
About 60% of GPP is for respiration
40% of GPP for growth/reproduction
Productivity is highest where temperatures are warm and water/solar energy are abundant
After drastic change (hurricane, fire, etc.) the amount of NPP tells us if the new system is more/less productive than the previous system
1.9 Trophic Levels
Law of conservation of matter
Matter cannot be created or destroyed but it can be transformed
Matter is constantly moving between the living and nonliving world
Autotrophs/producer
Heterotrophs/consumer
Herbivore /primary consumer
Carnivore / secondary consumer
Tertiary consumer
Detrivore: feed on the dead and decomposing organic matter by oral ingestion
Decomposer: organisms that decompose organic material
Scavenger: consume dead animals
Biomass: total mass
Amount of biomass present in an ecosystem at a particular time in its standing crop
Proportion of consumed energy that can be passed from one trophic level to another is ecological
1.10 Energy Flow and the 10%
The 10% rule is the transfer of energy from one trophic level to the next, only about 10% of the energy is passed on
The loss of energy that occurs when energy moves from lower> high trophic levels can be explained through the laws of thermodynamics
First law of thermodynamics: This is the law of conservation of energy. The law states in a closed system energy cannot be created or destroyed, it can only be transformed from one form to another.
Second law of thermodynamics: The second law of thermodynamics states that every time energy changes form it increases entropy. Entropy is the amount of disorder in a system.
1.11 Food Chains and Food Webs
Food web: model of interlocking pattern of food chains that depict the flow of energy and nutrients in two+ more food chains
Keystone species: a species that plays a far more important role in its community than its relative abundance might suggest
Negative feedback loop= output from a system moving in one direction acts as input
Moves system in the other direction
Input and output neutralize one another/stabilizes the system
Positive feedback loop: causes system to change further in the same direction (further from normal)
AP Environmental Science Course Review Part 1
80 mc questions in 90 minutes - 60% of exam score
3 FRQ in 70 minutes - 40% of exam score
Question 1: design an investigation
Question 2: analyze environmental problem + propose a solution
Question 3: analyze environmental problem + propose solution doing calculations
hypothesis and/or predictions
identify the independent variable - what treatments will you apply
identify the dependent variable - what will you measure
identify several variables to be controlled (very important)
describe the materials you would use to conduct the experiment. Be specific!
describe what you will actually do. Give a specific list of steps you’d follow.
describe how you will actually take and record data
describe how the data will be graphed and analyzed
state how you will draw a conclusion (claim-evidence-reasoning with comparison of outside sources)
Things to know….. Million= 106 Billion= 109 Mega= 106 (ex: 1,000,000 BTU/ 1 MBTU) Kilo= 103 (ex: 1000 watts/ 1 kW) Half Life 1 1/2 1/4 1/8 1/16 1/32 1/64 | Population Stuff…. Approximate population for: The world: 7.5 billion China: 1.3 billion India: 1.3 billion The US: 325 million Per Capita = Per Person |
Percent Percent is part divided by the whole times 100! Primary Productivity Gross primary productivity - respiration = net primary productivity | Population Math Population Density= Number of individuals/ area Growth Rate is a % B-D/ population size * 100 Rule of 70 DT = 70/ GR |
Percent Change | ENERGY KWh= kilowatts * hours Efficiency can be solved using ratios |
ALWAYS! EVERYTIME! SHOW YOUR WORK!
|
1963 (revised several times since) Clean Air Act (CAA): Includes provisions for:
Sulfur oxides, carbon monoxide, particulate material, volatile organic compounds, nitrogen oxides, ozone, lead
Providing resources to study air in order to inquest about the issue of atmospheric pollutants.
Setting enforceable regulations to limit emissions from stationary and mobile sources
Developing programs to monitor and reduce acid deposition
Establishing a program to phase out the use of chemicals that deplete stratospheric O³
Establishing a cap and trade (a system in which maximum allowable emissions are set for each industry; businesses that reduce their emissions to below the standards are awarded credits which they can sell to other businesses within their industry, creating economic incentive for reducing emissions).
1970 National Environmental Policy Act (NEPA): One of the first pieces of environmental legislation in the United States, NEPA was written to promote the idea of sustainability.
Environmental Impact Statement (EIS): Any major federal agency must submit an EIS for any activity that may have a harmful impact on the environment.
1970 Environmental Protection Agency (EPA): Formed under the Nixon Administration with the primary purpose of protecting human health and the environment and enforce environmental standards under a variety of state and local environmental laws.
1972 (revised several times since) Clean Water Act (CWA): A response to the 1969 Cuyahoga River catching fire in Cleveland, Ohio. Its mission is to restore and maintain the chemical, physical, and biological integrity of Americaʼs waterways and make them “fishable and swimmable.” Provisions intended to reduce and prevent point and nonpoint sources of water pollution, although there are no provisions regarding groundwater protection.
1973 Endangered Species Act (ESA): A far-reaching act that provides protection for any species that is determined to be threatened with extinction. Provisions include strict enforcement of habitat protection, a ban on any activity which disturbs or endangers the life of a listed species, and a ban on the import or export of any individual organisms or product derived from an endangered species.
1973 Convention on International Trade in Endangered Species of Wild Flora and Fauna (CITES): A multilateral treaty ensuring that international trade in specimens of wild animals and plants does not threaten the survival of the species in the wild and accords varying degrees of protection for more than 33,000 species.
1974 Safe Drinking Water Act (SDWA): Focuses on maintaining the purity of any water source that may potentially be used as drinking water, including both surface and groundwater.
1976 Resource Conservation and Recovery Act (RCRA): Also called the “Cradle-to-Grave Act,” sets specific regulations concerning the manufacture, transport, storage, use, and disposal of a host of hazardous chemicals. Its major provision requires extensive documentation at every step to ensure the hazardous wastes are disposed of properly.
1980 Comprehensive Environmental Response, Compensation, and Reliability Act (CERCLA): Also called the Superfund Act, established to handle industrial contamination in sites where no direct individual or party could be help responsible. Imposed a tax on the chemical and petroleum industries and authorized the federal government to respond to the release of hazardous substances. Also created a trust fund for cleaning hazardous waste sites when no responsible party could be identified.
1987 Montreal Protocol: A global effort and one of the greatest environmental success stories to date. Provisions include requiring participating nations to phase out the use of ozone-depleting chemicals (specifically CFCs) in favor of less harmful alternatives.
1997 Kyoto Protocol: Developed at a world summit to address measures for reducing greenhouse gas emissions. No real progress was made; when the US announced it would not sign the protocol the whole movement lost support
1938 Delaney Clause of Food, Drug, and Cosmetic Act: chemical additives “found to induce cancer in man” or in animals could NOT be approved for use in foods by the FDA
1.1 Introduction to Ecosystems
Presence of a species may be influenced by:
Fundamental niche: range of abiotic factors it can tolerate
Ability to disperse
Interactions with other species
Competition, predation, mutualism, commensalism
Competition: the struggle of individuals to obtain a limiting resource
Competitive exclusion principle: two species competing for the same limiting resource cannot coexist (CAN LEAD TO RESOURCE PARTITIONING)
The process of partitioning reduces competition between 2 species
Temporal: species use same resource at different time
Spatial: species reduce competition by using different habitats
Morphological: evolution of different body shapes or size
Predation: the use of one species as a resource by another species
True predators: kill their prey
Herbivores: consume plants as prey
Parasites: live on or in the organism they consume
Typically only consume part of their host, single parasites rarely cause death
Parasites that cause disease in the hosts are pathogens
Parasitoids: lay eggs inside other organisms
When hatch, larva slowly consume the host from inside out, causing the hosts death
Mutualism: interspecific interaction where both species benefit (acacia tree and ants)
Commensalism: ons species benefits but the other is neither harmed nor helped (clownfish /anemone)
Parasitic: one benefits and the other organism is harmed
1.2 Terrestrial Biomes
Tundra Biome
Cold & treeless, with low growing vegetation
Arctic tundra – N most regions of N. Hemisphere
Very short growing season (4 months during summer)
Upper layer of soil thaws, creating pools of standing water- ideal habitat for mosquitoes
Permafrost- underlying subsoil, impermeable, permanently frozen- prevents deep rooted plants
Little precipitation
Plants: lichen, moss, woody shrubs
Soil: slow rate of decomposition resulting in accumulation of organic matter in the soil over time with relatively low levels of soil nutrients
Boreal Forest (Taiga) Biome
Coniferous (cone bearing) evergreen trees (Ex: Pine and Spruce)
Evergreen- green year round
Europe, Russia, N. America
Plant growth constrained by temperature
Decomposition a slow process (cold) & low nutrient content in waxy needles – thick layer of organic material but soil low in nutrients
Some deciduous trees- lose leaves (Ex: Birch, Maple, Aspen)
Extensively logged for pulp, paper, and building materials
Temperate Rainforest Biome
Mid-latitude- west coast of N. America from Northern CA to Alaska
Ocean water is source of water vapor
Mild summers and winters
12 month growing season (almost)
Coniferous trees most common (Ex: Spruce, Cedar, Fir, Hemlock, Redwoods)
Redwoods (Sequoia sempervirens)
Ferns and mosses (can live in nutrient poor soil) are found under trees
Nutrients released are uptaken by trees or leached out by abundant rain
Temperate Seasonal Forest Biome
Deciduous trees
Warm summer & cold winter
Eastern USA, Japan, Europe, China
Warm summers favor rapid decomposition
Soils have more nutrients because deciduous leaves decompose faster
Historically one of first biomes to be converted to agriculture
Woodland/Shrubland Biome
Hot/dry summers and mild/rainy winters
Southern CA = chaparral
Wildfires
Fire dependent plant species
Drought resistant shrubs (Ex: yucca, scrub oak, sagebrush)
Soil low in nutrients from winter rains
Agriculture: grazing animals and deep rooted crops like grapes to make wine
Temperate Grassland
Cold/harsh winters & hot/humid winters
Great Plains of N. America = prairies
S. America = pampas
Central Asia/E. Europe = steppes
Fires
Plants: grasses & nonwoody flowering plants
Long growing season & rapid decomposition – nutrient rich soil
98% of tall grassland in USA has been converted to agriculture
Short grass prairie is converted to growing wheat
and grazing cattle
Tropical Rainforest
Warm/wet @ 20° N/S latitude
ITCZ
High productivity, extremely high decomposition rate
Soils lose nutrients quickly
Slash and burn agriculture
More biodiversity per hectare than any other terrestrial biome
Plant: epiphytes (hold small pools of water to support an aquatic ecosystem)
Tropical Seasonal Forest/Savanna
Lion King!
Warm temperature & wet season/dry season
Dense stands of shrubs and trees
Grazing & fire discourage growth of smaller woody plants
Warm temperature promotes decomposition but low rain prevents plants from using soil nutrients
Subtropical Desert
Hot/extremely dry
Plant adaptations: small or nonexistent leaves modified into spines, thick waxy outer layer, most photosynthesis occurs in plant stem
Less than 10 inches of rain/year
1.3 Aquatic Biomes
Freshwater biomes: streams, rivers, ponds, lakes that are used for drinking water
Marine biomes: oceans, coral reefs, marshlands, and estuaries
Algae in marine biomes supply a large portion of the Earth’s O2 and take in CO2 from the atmosphere
The global distribution of nonmineral marine natural resources such as dif fish varies because of the combination of salinity, depth, turbidity, nutrient availability, and temperature
Streams: the faster a stream flows, the greater the amount of dissolved oxygen in it
Rivers: water moves slower in a river and debri settles on the bottom
Usually have more nutrients and less dissolved oxygen
Littoral zone: shallow area of soil and water near the shore where algae/emergent plants grow
Limnetic zone: open water, where rooted plants can no longer survive
Phytoplankton are the only photosynthetic organisms, extends to as deep as sunlight can penetrate
Profundal zone: zone where sunlight cannot penetrate so producers cannot survive
Benthic zone: muddy bottom of a lake or pond beneath the limnetic or profundal zone
Oligotrophic: low levels of organic matter
Tend to be deep and clear, oxygen rich bottom supports cold water fish like trout, phosphorus is limiting
Mesotrophic: more organic matter
Oxygen level in lake bottom is low
Eutrophic: high levels of organic matter
Abundant plant growth, poor clarity, oxygen poor bottoms
Freshwater Wetlands
Aquatic biomes that are submerged or saturated by water for at least part of each year, but shallow enough to support emergent vegetation.
These include swamps, marshes, and bogs.
Swamps: wetlands with emergent trees
Marshes: wetlands that contain primarily non woody vegetation, like cattails and sedges
Bogs: acidic wetlands that typically contain sphagnum moss and spruce trees
Marine Biomes: salt marshes, mangrove swamps, intertidal zones, coral reefs, open ocean
Mangrove Swamp
Occur along tropical and subtropical coasts
Tree roots submerged in water
Trees are salt tolerant
Help protect coast from erosion & storm damage!!!
Falling leaves produce nutrient rich environment
Provide sheltered habitat for fish and shellfish
Estuaries
Area where a river meets an ocean
Mix of salt and freshwater
Located near coastlines, border land
Extremely fertile
Nutrient levels are higher than both salt and freshwater
Salt Marsh
Found along the coast in temperate climates and contain non woody emergent vegetation.
The salt marsh is one of the most productive biomes in the world.
Naturally occurring wetlands wound within the intertidal zone
Ecosystem service: absorb storm surge
Intertidal Zone
Band of coastline the exists between high and low tide
Range from steep and rocky to broad and sloping mudflats
Stable environment when submerged during high tide
Harsh conditions during low tide when organisms are exposed to direct sunlight, high temperatures and desiccation
EX: barnacles, sponges, algae, mussels, crabs, sea star
Coral Reef
Found: warm shallow waters beyond shoreline
Earth’s most diverse marine biome
Coral- tiny animals the secrete layer of limestone (calcium carbonate) to form external skeleton
Animal lives inside this tiny skeleton with tentacles that draw in plankton and detritus
Coral lives in water that is relatively poor in nutrients and food
Therefore have a relationship with single celled algae that live in the tissue of corals called zooxanthella
Algae use CO2 captured during photosynthesis to produce sugar and nutrients… then release this to the coral animal
Coral gains energy from sugar… and the algae gets CO2, nutrients and a safe place to live
Coral bleaching
When algae in coral die- without algae the coral dies
Cause: turbidity, ocean temperature increase, pollution, tourism, ocean
Open Ocean
How deep the light penetrates depends on the amount of sediment & algae suspended in the water
Will not exceed 200 m (approximately 650 feet)
Is divided into zones
Photic- light
Aphotic- no light
Benthic- bottom
Photic zone: relatively shallow part of the ocean above the drop-off of the continental shelf
Enough sunlight for photosynthesis, approximately 200 m/660 ft in depth
Intertidal zone: area where the ocean meets the land between high and low tides
Pelagic zone: sometimes called the open zone
Salinity, depth, temperature, turbidity (loss of transparency), nutrient availability in the ocean varies
1.4 The Carbon Cycle
Carbon has 2 stages: the fast stage associated with living organisms
Slow stage: associated with dead organisms (fossil carbons)
1. When plants carry out photosynthesis the use CO2 from the atmosphere
Plats release some of the CO2 back into the atmosphere with cellular respiration but keeps most of it within their plant tissues
2. The plant will die or be eaten by another organism that will die; the dead matter contains carbon will be processed by decomposers and exist in soil so more plants can use it
Decomposition: microbes, bacteria, fungi break down organic matter and release CO2 (aerobic decomp), CH4 (anaerobic decomp)
1. Carbon exchange occurs in the ocean: the ocean absorbs some CO2 form the atmosphere and release CO2 back into the atmosphere
Sedimentation: the CO2 combines with calcium ions in the water to form calcium carbonate that sinks to the bottom of the ocean and accumulated
Dissolved CO2: CO2 DISSOLVES into the ocean from the atmosphere and moves between atmosphere and ocean via direct exchange
Ocean is the largest carbon sink
Sequestration: storage of carbon in biomass, sediments, limestone, fossil fuels
1.5 The Nitrogen Cycle
Nitrogen, phosphorus, potassium, calcium, magnesium, and sulfur
Most reservoirs in which nitrogen compounds occur hold them for relatively short periods of time
Atmosphere is the major reservoir of nitrogen (78% of the air on Earth)
nitrogen/phosphorus: often a limiting nutrient
Limiting nutrient: often required for the growth of the organisms but available in a lower quality than other nutrients
Nitrogen (N2 in air is useless to organisms and must be fixed into usable form: nitrate, nitrite, ammonia)
Nitrogen Fixation: N2>NO3
Bacteria in roots of legume
Usable form for plants (nitrite)
When animals eat these plants usable nitrogen is acquired (assimilation)
Ammonification: when plant/animal dies or excrete waste, microorganisms covert their N compounds to ammonia
Nitrification: most plants cant use ammonia so they convert it tinto nitrate (NO3)
One group of soil bacteria change ammonia to nitrites
Another group of bacteria convert nitrites to nitrates
Denitrification: other bacteria convert ammonia, nitrate, and nitrite back into N2 - returning into the atmosphere
Assimilation: producers take up N in form of ammonia, ammonium, nitrate, nitrite, and incorporate it into their tissues
Natural way to fix nitrogen: lightning
2 plants that fix nitrogen: legumes, rye (grass)
Nitrate is a limiting nutrient essential to plant growth- burning soil vegetation increases nitrate levels , so testing would would allow the scientist to measure how much the levels are increasing by burning to help determine the impact of wildfires on plant growth and succession
1.6 The Phosphorus Cycle
No atmospheric component (is a limiting factor)
Limitation imposed on return from the oceans to land to make phosphorus scarce in aquatic and many terrestrial ecosystems ( limiting factor)
Found as phosphate (PO4 3): mineralization of organic phosphorus back into inorganic phosphorus >slow cycle in rocks
N & P runoff and algal bloom= hypoxic
Major reservoirs of phosphorus: rock and sediment that contain phosphorus-bearing minerals
1.7 The Hydrologic Cycle
Powered by the sun> movement of water in its various solid, liquid, and gaseous phases between sources/sinks
Oceans are the primary reservoir of water at the Earth’s surface, with ice caps/groundwater as smaller reservoirs
1. Heat from sun causes water to turn into water vapor>rise into atmosphere
Water from ground>air by either evaporating from body of water or ground or plants can release water through transpiration
2. Once in atmosphere, comes down to Earth in form of precipitation
Can result in surface runoff (water slides from the and back into body of water); percolation (water will be absorbed by the ground and become part of groundwater stores); plants uptake to use for photosynthesis
1.8 Primary Productivity
Primary productivity: rate at which solar energy is converted into organic compounds via photosynthesis over a unit of time
Gross primary productivity (GPP): total rate of photosynthesis in a given area
Net primary productivity (NPP): rate of energy storage by photosynthesizers in a given area after subtracting the energy lost to respiration
Measured in units of energy per unit area per time (ex. kcal/m^2/yr)
Producers capture about 1% of available energy via photosynthesis> GPP
About 60% of GPP is for respiration
40% of GPP for growth/reproduction
Productivity is highest where temperatures are warm and water/solar energy are abundant
After drastic change (hurricane, fire, etc.) the amount of NPP tells us if the new system is more/less productive than the previous system
1.9 Trophic Levels
Law of conservation of matter
Matter cannot be created or destroyed but it can be transformed
Matter is constantly moving between the living and nonliving world
Autotrophs/producer
Heterotrophs/consumer
Herbivore /primary consumer
Carnivore / secondary consumer
Tertiary consumer
Detrivore: feed on the dead and decomposing organic matter by oral ingestion
Decomposer: organisms that decompose organic material
Scavenger: consume dead animals
Biomass: total mass
Amount of biomass present in an ecosystem at a particular time in its standing crop
Proportion of consumed energy that can be passed from one trophic level to another is ecological
1.10 Energy Flow and the 10%
The 10% rule is the transfer of energy from one trophic level to the next, only about 10% of the energy is passed on
The loss of energy that occurs when energy moves from lower> high trophic levels can be explained through the laws of thermodynamics
First law of thermodynamics: This is the law of conservation of energy. The law states in a closed system energy cannot be created or destroyed, it can only be transformed from one form to another.
Second law of thermodynamics: The second law of thermodynamics states that every time energy changes form it increases entropy. Entropy is the amount of disorder in a system.
1.11 Food Chains and Food Webs
Food web: model of interlocking pattern of food chains that depict the flow of energy and nutrients in two+ more food chains
Keystone species: a species that plays a far more important role in its community than its relative abundance might suggest
Negative feedback loop= output from a system moving in one direction acts as input
Moves system in the other direction
Input and output neutralize one another/stabilizes the system
Positive feedback loop: causes system to change further in the same direction (further from normal)