AP Environmental Science Biomes, APES: The Living World Unit 1

Temperate Deciduous Forest

-Cool Winters, Warm Summers (Seasonal Variation)
-Precipitation is relatively evenly spread throughout the year
-Deciduous Trees (Oak, Beech)
-Europe, China, Eastern North America
-Northern Hemisphere
-Good Soils
-US has largest Deciduous forest

Old-growth forest

one that has never been cut; these forests have not been seriously disturbed for several hundred years. Ex. Alaska

Temperate Grassland

-Cool Winters, Warm Summers (seasonal variation is more extreme than temperate deciduous forests)
-Limited amount of precipitation
-Frequent fires (no trees)
-Also called prairie or steppe
-Northern Hemisphere
-North America, Middle East, Europe, Asia
-Very fertile soils (used for agriculture)

Temperate Rainforest

-Cool Winters, Warm Summers (Seasonal Variation)
-Large amount of precipitation (Less rain in winters)
-Coniferous Trees
-Provide lumber and paper
-Northern Hemisphere
-East coast of North America and Canada
-Fertile soils that are susceptible to land slides and erosion if forests are cleared

Tropical Rainforest

-Warm all year round
-Very high amount of precipitation (300-500 mm per month)
-Southern Hemisphere
-Central America, Africa, South America, Southeast Asia
-Great Biodiversity
-Poor, thin soils

Tropical Dry Forest/Tropical Deciduous Forest

-Warm all year round
-Extreme wet and dry seasons
-Wet summer (October to April) and dry winter (May, June, July, August, September)
-Southern Hemisphere
-India, Africa, South America, northern Australia
-Erosion-prone soils

Savanna (Tropical Grasslands)

-Slight seasonal variation (warmer in summer)
-Extreme wet and dry seasons
-Wet Summer (not as wet as tropical dry forest)
-Southern Hemisphere
-Isolated Trees
-Africa, South America, India, Australia
-Zebras, Giraffes, Gazelles

Desert

-Driest Biome
-Barely an rainfall
-Slight seasonal variation
-Saline soils
-Little Vegetation
-Temperatures drop at night
-Northern Hemisphere
-Africa, Mexico, Middle East, Asia

Tundra

-Coldest Biome
-Warmer in summers, but still cold (5 degrees celsius)
-Freezing in winters (-20 degrees celsius)
-Northern Hemisphere
-Dry
-Slightly wet summers
-Soil is permanently frozen (permafrost)
-Also occurs as alpine tundra at the tops of mountains
-Northern Europe, Northern Canada, Northern Asia, Greenland

Boreal Forest/Taiga/Coniferous Forest

-Largest Biome
-Northern Hemisphere
-Coniferous Trees (Pinecones)
-Cold. Cooler in summers (never above 20 degrees Celsius)
-Moderate Precipitation
-More wet in summer than winter
-Poor soils
-Moose, Wolves, Lynx, Bears
-Northern Europe, Canada, Northern Asia
-Russia has the largest Boreal Forest biome

Chaparral

-Densely thicketed
-Highly seasonal
-Cool, wet winters and warm, dry summers
-Induced by oceanic influences
-Northern Hemisphere
-California, Chile, Australia
-Frequent fires

Desertification causes

loss of topsoil, increased soil salinity, damaged vegetation, regional climate change, decline in biodiversity; Australia is the country with the greatest percentage of land area affected by desertification

Energy Flow

Sun--> Producers--> Primary Consumers --> Secondary Consumers-->Tertiary Consumers

Producers

Autotrophs. Produce food from photosynthesis.

Consumers

Heterotrophs. Use bodies of other organisms as a source of energy.

Primary Consumers

Herbivores. Only eat producers.

Secondary/ Tertiary Consumers

Carnivores.

Omnivores.

Eat plants and animals.

Detritus Feeders/Detritivores

Consumer that eats organic matter, such as carcasses, leaf litter, and feces.
-snails, clams, worms

Forms of Energy

1. Solar
2. Chemical
3. Radiant
4. Thermal
5. Nuclear
6. Electrical

Energy

Capacity or ability to do work.
-often expressed in kilojoules/kilocalories (Kcal)
-One Kcal raises H20 one degree celsius.

Decomposers or Saprotrophs

microbial heterotrophs that break down dead organic material and use it as energy.

Food Chain

energy from food passes from one organism to the next.

Trophic Level

Organism's position in a food chain, determined by its feeding relationships.

Food Web

interlocking food chains that connect all organisms in an ecosystem.

How many directions does energy flow?

One.

Ecological Pyramids

Graphically represent the relative energy values of each trophic level.
-Pyramid of Numbers
-Pyramid of Biomass
-Pyramid of Energy

Pyramid of Numbers

Shows number of organisms at each trophic level in a given ecosystem, with greater numbers illustrated by the larger of the pyramid.

Pyramid of Biomass

Total biomass (quantitive estimate of the total amount of living material) at each successive trophic level.

10% rule

Progressive reduction of biomass in succeeding trophic levels. 90% reduction per level in Biomass Pyramid.

Potential Energy

Stored Energy.

Kinetic Energy

Energy of Motion.

Pyramid of Energy

Expresses energy content as Kcals/square meter/year for each trophic level.
-Energy dissipates into the environment when going from one level to the next.
-Dramatic reduction in energy at each level explains why there are so few trophic levels.

Gross Primary Productivity (GPP)

Rate at which energy is captured in Photosynthesis.

Net Primary Productivity (NPP)

Equal to gross productivity minus energy used by primary producers for respiration.
-Most energy is used for cellular respiration to move muscles, and maintain/repair cells.
Extra energy is used for growth and production of young.

Energy per unit area of time

How GPP and NPP are expressed.

What is the Biome with the highest NPP?

Rainforest. Ecosystems differ in productivity.

What species consumes the most resources?

Humans. They use 32% of annual NPP of land-based ecosystems and only represent .5% or total biomass.

Evolution

Cumulative genetic changes that occur over time in a population of organisms. It explains many patterns observed in the natural world.

Adaptation

Evolutionary modernization that improves the changes of survival and reproductive success of a population.

Natural Selection

Proposed by Darwin in his "Origin Species" book. It made four observations about the world.
1. Overproduction
2. Variation
3. Limits on Population Growth/ Struggle for Existence
4. Differential Reproductive Success

Overproduction

Each species produce more offspring than will survive to maturity.

Variation

Individuals of a population exhibit variation; unique traits that are inherited.

Limits on Population Growth/ Struggle for Existence

Resources are limited.

Differential Reproductive Success

those with favorable characteristics will survive, reproduce, and pass on their traits.

Galapagos

Where Darwin formulated his ideas of evolution while studding Finches.

Community

An association of different populations of organisms that live and interact together in the same place and same time.
-organisms interdependent: compete for resources and rely on one another

Ecosystem

Biological community and its abiotic environment.

Succession

Stages of progress , the replacement of one type of community by another at a single location over a period of time.
-Once thought to lead to a stable and persistent community (Climax Community in a forest)
-Now believed that communities are in a constant state of disturbance.

Primary Succession

Begins in an environment not inhabited before.
-No soil
-Bare rock surfaces (lava/rock sculpted by glaciers)
-Begins with Lichens which secrete acid and help break rock apart.
-Lichens-->mosses-->grasses-->shrubs-->trees

Sand Dunes

Studied by Henry Cowles in 1880s. Example of Primary Succession.

Secondary Succession

Begins in an environment following destruction of or part of an earlier community.
-Fire, Old farmland, tornadoes, etc.
-Take more than 100 years.

Secondary Succession on and abandoned field would look like what?

Annual weeds-->annual perennials-->pine seedlings/saplings-->young pine forest/understory hard woods-->mature hardwoods.
Animals follow succession and changes in vegetation.

Symbiosis

Individuals of one species live in or on individuals of another species.

Symbionts

Partners of symbiotic relationships.

Coevolution

Interdependent evolution of two or more interacting species
-Flower and its pollinator
-Three categories
1. Mutualism
2. Commensalism
3. Parasitism

Mutualism

Both partners benefit.
-Clown Fish Anemone
-bacteria and legumes
-fungi and roots

Commensalism

One organism benefits the other is neither helped nor harmed.
-tropical tree and epiphytes

Parasitism

One organism takes nourishment from the other. The parasite may weaken host, but rarely kills it (if it kills it, it is a pathogen).
-leech
-ticks
-tape worms

Predation

Animals eating other animals or plants.

Adaptions

Predatory strategies: Pursuit and ambush.
Prey strategies: Plant and animal defenses

Competition

Occurs when two or more individuals compete to use an essential resources.
-Intraspecific: competition with same species
-Interspecific: between different species.

Ecological Niche

An organisms role; totality of organisms adaptions, its use of resources, and lifestyle.
-Includes Habitat (local environment in which an organism lives)

Fundamental Niche

The full range of conditions that a species can tolerate and resources it can use.

Realized Niche

The part of its fundamental niche a species actually occupies
-An organism may not fulfill its fundamental niche because it is forced out by an invasive species.

What determines and Ecological Niche?

A species structural, physiological, and behavioral adaptations, along with limiting resources. Adaptions determine an organisms tolerance for environmental extremes, and a scare, limited resource restricts a niche.

Competitive Exclusion

Fundamental niches many overlap between species. No two species may indefinitely occupy the same niche in the same community because of competitive exclusion.

G.F Gause

Had a set of experiments that showed that competition between species determines an organisms realized niche.
-Two species of bacteria. Thrive apart, but together only one thrived.
-Conclusion: One set of conditions favor one species over another.

Resource Partitioning

coexisting species niches' differ from one another; may include time of feeding, location, rest sites, etc.

Species Richness/Diversity

The number of different species in a community; varies from one community to the next.
-High in coral reefs and rain forests.
-Low in mountain tops and deserts.
-Determined by abundance of potential ecological niches, closeness to the margins of adjacent communities, geographical isolation, dominance of one species over another, geographical history and habitat stress.
-Fragmenting a large park into many smaller parks due to human interaction causes a decrease in species diversity

crop plants

give higher yields; low diversity
are resistant to certain diseases
are resistant to certain insect pest damage
are hardier (so that they survive in harsher climates or are productive for longer periods of the year) ex. corn
have a better balance of nutrients in the crop

Complex Community

Offers more niches than a simple one.

Ecotone

Transitional zone where two or more communities meet; contains all or most of the niches of the adjacent communities as well as niches specific to the ecotone.

Edge Effect

Change in species composition produced at ecotones.

Species richness is _________ related to isolation.

Inversely.
-Difficult to reach and colonize island
-Some species become extinct and are not readily replaced.

Species richness is ______ when one species has a large, disproportionate share of resources.

Reduced.

Species richness is ________ related to environmental stress.

Inversely.
-Species richness declines in a highly polluted stream.

The older an area of land, the _____ species richness. The younger an area of land, the ______ species richness.

more (example: rain forest), less (example: areas scoured by glaciers).

Ecosystem Services

Important environmental benefits and ecosystem provides. The greater species richness, the better supply of ecosystem services.
-clean H20 and air
-fertile soil

Community Stability

ability of a community to withstand environmental disturbances.
-community with more species richness is more stable

Biome

A major type of ecosystem with distinctive climates (temperature/rainfall), and organisms.
-Tundra
-Taiga
-Temperate Rain Forest
-Temperate Deciduous Forest
-Grassland
-Chaparral
-Desert
-Savannah
-Tropical Rainforest

Tropical Rainforest

-sunlight year round
-little seasonal variation
-climate ideal for growing plants
-most species rich biome
-soil usually thin and poor
-many trees form above ground roots
-plants grow in layers (canopy and undergrowth)
-camouflaged animals are common
-Threatened by logging, and farming
-plants and animals have become extinct
-Used to cover 20% of earth, now only 7%
-Costa Rica=high rate of deforestation, working towards...
1. protecting national parks
2. sustainable agriculture
3. encouraging tourism
-American pharmaceutical sending money to protect.

Temperate Forest

-North America Pacific NW, South America, Australia, and New Zealand
-Drop leaves each fall
-Soil rich and deep
-Plants grow in layers (canopy and undergrowth)
-Plants adapted to seasonal weather changes
-Cold winters warm summers
-Numerous habitats due to layers of vegetation
-Birds migrate out in the winter
-Bears and some other animals hibernate

Taiga

-terrain rough
-forest floor sparsely vegetated
-just below Arctic Circle
-winters long and extremely cold
-frost free season can be as short as 50 days
-constant daylight in summer
-most precipitation falls as snow
-conifer trees; seeds grow cones and needles don't shed plus retain H2O
-needles are acidic and when they fall acidify the soil; most plants cannot grow in acidic soil=bare forest floor

Tundra

-cold, wintery, dry
-Northern Hampshire, south of Polar Ice Caps; in Alaska, Canada, Greenland, Iceland, Norway, Asia
-one of largest biomes
-10% of earth
-few organisms, fragile ecosystem
-little precipitation, most falls as ice or snow
-summer days long and cool
-Active zone may be as thin as 8cm
-Frozen soil below (Permafrost)
-dense mat of grasses, mosses, and other plant life cover active zone during summer; helps insulate ground and keep permafrost from melting
-trees small; usually less than one meter
-short growing season (60 days) and low temps make for slow recovery time of vegetation in comparison to other biomes
-tracks from wagons 100 years ago still visible
-most animals are migratory
-few predators=good place for birds and caribou to raise young
-Arctic foxes, musk oxen, polar bears, and wolverine live year round
-Lichens, eaten by caribou, are pollution sensitive and declining over the years=decline in caribou

Desert

-lack of precipitation and extreme temps limit plant and animal life
-few, short thunderstorms are main source of precipitation
-desert pavement causes most rain to run off
-low moisture=great variation in temps.
-hot at day, cold at night
-plants need to absorb scare H2O from ground and retain it
-cactus spines retain H20, and are a source of H20 for animals
-plants have shallow roots and over wide area, or deep roots to reach H20
-insects and reptiles have outer coating that reduce H20 loss
-Rodents spend days underground, many are nocturnal

Grassland

1. Savannah
a. Tropical
-west african plains
-Tropics, near the equator
-greatest collection of grazing animals in the world as well as predators
-little rain, few trees
-fires during dry season
-plants resistant to droughts, fires and grazing animals
-RUNNERS; long stems below the ground protect from fire
-TUFTS; large clumps of coarse grasses. Have thorns and sharp leaves to protect from animals
-plants grow rapidly
-animals take advantage of short rainy season
-large animals migrate looking for H20
-animals eat vegetation at different hight to cut down competition
b. Temperate
2. Grassland
a. Tropical
-closest to equator
-hot all year
b. Temperate
-further from equator
-hot summers, cold winters
-tall grass or short grass
-soil very fertile
-interiors of continents
-little rain for trees to grow
-begin at edge of desert biome and stretch to forest biome
-fire leave nutrients and minerals=more grass growth
-grazing animals (bison)
-burrowing animals aerate ground; helps H20 plus nutrients reach roots quickly

What affects the size and texture of grass?

Water. Drier areas= thinner and finer leaves. Wetter areas have thick leave (bamboo).

Steeps vs. Prairies

Steeps:
-rain evaporates quickly
-short grass, mostly bunchgrass
-roots are shallow
Prairies:
-soil hold water well
-root form a mat of sod
-soil held together, resists erosion
-as grass dies layer of organic matter, or HUMUS is formed. Helps hold H20 and provides nutrients.

Problems with Steeps and Prairies?

-Farming and Ranching
-Overgrazing, replacing of native grasses with those poorly adapted to the area (dust bowl)
-Native animals displaced (bison, wolves)

What does Photosynthesis do to carbon?

It removes CO2 from the air by plants and fixed into compounds such as sugar.

What does respiration do to carbon?

It returns CO2 into the atmosphere.

Molecules essential to life contain ________.

Carbon, Nitrogen, Oxygen, Hydrogen, Sulfur, Phosphorous

What forms are Carbon found in?

CO2,
CO3(2-),
HCO3(-)

What are some things that keep Carbon in biological molecules longer?

Large, old trees, and fossil fuels

The atmosphere is 78% _________.

Nitrogen. (N2)

Is N2 stable?

Yes. It will not readily bond with other elements. Must be broken apart first through the Nitrogen Cycle.

Nitrogen Cycle

1. Nitrogen Fixation
2. Nitrification
3. Assimilation
4. Ammonification
5. Denitrification

Nitrogen Fixation

N2--> NH3

-Combustion, volcanoes, lighting and industry supply enough energy to break apart N2
-bacteria in the soil (living in nodules or swellings of plant roots) can split N2 with the enzyme "nirtogenase" which only works in the absence of oxygen.

Nitrification

NH3 or NH4--> NO3

1. Soil bacteria converts NH3 or NH4
2. Other soil bacteria oxidizes nitrite to nitrate