Vocabulary & Key Concepts
Ecosystem Ecology, Biogeochemical Cycles & Energy Flow
1. Biosphere - all of the ecosystems combined from the deepest ocean bottom to the highest mountain
peak. Basically, all of the living parts of the world
2. Producer - the fellas that can use the energy of the sun to produce usable forms of energy. Also known
as autotrophs.
3. Photosynthesis - how producers make their food. They use solar energy to rearrange carbon dioxide
(CO2) and water (H
2O) into super awesome glucose (C6H
12O6) and waste product O
2
6H2O + 6CO
2 + ENERGY → C6H
12O6 + 6O
2
4. Cellular respiration - when producers AND consumers take glucose and smash into little itsy bitsy
pieces to release the awesome energy stored in there by producers, which they store into ATP
(“batteries”) that power all of the cool things that the cell has to do to make us be alive and stuff
“Smash into little itsy bitsy pieces” = C6H
12O6 + 6O
2 → 6H2O + 6CO
2 + ENERGY
5. Aerobic respiration - when cellular respiration happens in the presence of oxygen
6. Anaerobic respiration - when cellular respiration happens in the absence of oxygen. It results in less
ATP being made, but it will work in a pinch. Our muscles do it when we work out too much, yeast do it
(this is why we use it to make bread! The CO2 bubbles makes it all fluffy)
7. Consumer - the ones that rely on autotrophs for energy since they can’t do the photosynthesis (which
should be obvious, since going to the beach just gives you a sunburn and makes you hungrier). Also
known as a heterotroph
8. Herbivore - a consumer that only eats producers. Also known as a primary consumer.
9. Carnivore - consumers that eats herbivores/primary consumers. Also known as secondary
consumers.
10. Tertiary consumer - a carnivore that eats secondary consumers.
11. Trophic levels - the successive levels of organisms consuming one another.
12. Food chain - the sequence of consumption from producers to tertiary consumers. The arrows go in
the direction of the energy. Grass → grasshopper → frog → snake
13. Food web - a bunch of food chains put together, since it’s unrealistic that an organism eats only one
type of organism. A great visual for how complicated ecosystems can be, since changing just one thing
can actually upset a lot.
14. Scavenger - an organism that eats dead animals. Yeah, gross, but the alternative is much worse!
Think vultures.
15. Detritivore - an organism whose speciality is breaking down dead tissues and waste products into
smaller particles. Like dung beetles!
16. Decomposers - fungi and bacteria that convert organic matter into small elements and molecules that
can be recycled back into the ecosystem
17. Gross primary productivity (GPP) - the total amount of solar energy that producers in an
ecosystem capture via photosynthesis over a given amount of time (all of the glucose and the glucose
derived products)
18. Net Primary Productivity (NPP) - the energy captured by producers in an ecosystem minus the
energy producers respire. (since they’re going to take some of the glucose they made and use it for their
own life things)
Basically, the GPP is like the total amount an employer pays you, and NPP is the
amount leftover after taxes. NPP is useful to know because it’ll tell you how much
energy is available for that ecosystem and all of the consumers. If there is a high
NPP, we’d say it’s very productive and can support a lot of life. If it has a low
NPP, it’s not very productive and can’t support a lot of life.
It’s also important to note that GPP and NPP are measured as a rate (grams of
Carbon PER square meter PER year → gC/m2/year )
19. Biomass - the total mass of all living matter in a specific area. The NPP determines how fast biomass
can be made in an area.
20. Standing crop - the amount of biomass present at a particular time.
(wait what? Let’s put this together. A slow-growing forest has a low productivity, thereby
adds only a little biomass every year. But the standing crop of the whole forest is HUGE! There is A
LOT of mass present if you could put it on a triple beam balance. I wouldn’t. It would break.
But in an ocean, there is a lot of algae that grow really fast so they’re really productive! This
means they make a lot of biomass every year.But they’re also very tasty to sea creatures and gets
eaten right away, so the standing crop of algae is very small. You probably could measure it on a
triple beam, but I still wouldn't since that’s gross.
21. Ecological efficiency - proportion of consumed energy that can be passed onto the next trophic level.
They range from 5-20%, but averages 10% so that’s the number you’ll see everywhere. What this
essentially means is that when a snake eats a mouse, 10% of the mouse molecules actually end up going
into building a snake. When a hawk eats a snake, only 10% of the snake molecules end up going into
building a hawk.
22. Trophic pyramid - a pretty visual that shows the distribution of biomass, numbers, or energy among
trophic levels
23. Biogeochemical cycle - movement of matter within and between ecosystems
24. Hydrologic cycle - movement of water through evaporation, precipitation, infiltration (water that
percolates through the soil), surface runoff (from precipitation falling on the land’s surface), and plant
uptake
25. Transpiration - release of water from leaves during photosynthesis
26. Evapotranspiration - the combined amount of transpiration and evaporation
27. Runoff - water that moves across the land surfaces and into streams and rivers
28. Carbon cycle - movement of carbon through atmosphere-water exchange, photosynthesis, respiration,
combustion, extraction, sedimentation, and burial
29. Limiting nutrient - nutrient essential for the growth of an organism that’s available in a lower
quantity than other nutrients
30. Macronutrient - one of six key elements that organisms need a lot of → nitrogen, phosphorus,
potassium, calcium, magnesium, and sulfur
31. Nitrogen cycle - movement of nitrogen through nitrogen fixation, mineralization, nitrification,
denitrification, assimilation, and leaching. Possibly the most confusing so obviously AP’s favorite!
32. Nitrogen fixation - a process by which some organisms can convert nitrogen gas molecules directly
into ammonia. Why is this a big deal? We’re surrounded by atmospheric N2 and we need nitrogen but
the strong triple bond in N2 is impossible for us to break to be able to use the nitrogen. But nitrogen
fixing bacteria found in soil and in the root nodules of some plants can do it, and take N2 and turn it
into NH3 and that’s much easier to use.
33. Nitrification - the conversion of ammonium (NH4) into nitrite (NO2) and then into nitrate NO3.
Special bacteria do this. This is important because NO3 is the favorite form of nitrogen and is used
readily by producers
34. Assimilation - process by which producers incorporate elements into their tissues. This is a big deal
because it can then be used to make proteins and DNA which you need for life. Consumers then get the
nitrogen stored in plant tissue by eating them.
35. Mineralization - the process by which fungal and bacterial decomposers break down the organic
matter found in dead bodies and waste products and convert it into inorganic compounds. These guys
are important so it can begin its journey back into the atmosphere and start the cycle all over again.
Sometimes it’s called ammonification because they usually make ammonia.
36. Denitrification - final step where nitrate is converted to nitrous oxide N2O and eventually N2 which
is then emitted back into the atmosphere.
37. Leaching - transportation of dissolved molecules through the soil via groundwater. When we use
fertilizers, the nitrates in there get LEACHED.
38. Phosphorus cycle - movement of phosphorus through the biosphere via geological uplift, phosphate
mining, weathering of rocks, assimilation/decomposition, and leaching of fertilizers and detergents.
This is the only cycle that doesn’t have a component in the atmosphere, which is why it “turns” so slowly
39. Algal bloom - a rapid increase in the algal population of a waterway. This happens as a result of the
leaching of excess phosphates (from inorganic fertilizers and household detergents) and nitrates
(inorganic fertilizers).
Initially, yes, it’s disgusting, but that’s not the worst part! It first leads to decreased light availability
for aquatic plants...sad. But the worst part is actually when they die. As they die, they are
decomposed by aerobic bacteria. Aerobic should always ring a bell in your head that says OXYGEN!
Bacteria use oxygen to break down the algae, and the only place that oxygen can come from is the
dissolved oxygen in the water. Which SUCKS for everything else in there that need oxygen, who find
they can’t get enough and “suffocate”
40. Hypoxic - low in oxygen. This is what we call the water that’s had all of the oxygen sucked out of it by
aerobic bacteria digesting the dead algae. They’re sometimes referred to in common talk as “dead
zones” since creatures that need oxygen (shellfish, fish, other aquatic animals…) die die die [but if
you’re an anaerobic bacteria that don’t need no oxygen life is good for you my friend...too bad you’re
useless to the fishing industry]
41. Sulfur cycle - the movement of sulfur through the biosphere by sedimentation, extraction,
combustion, acid precipitation, runoff, weathering, assimilation/decomposition
,
42. Disturbance - not in the Force, but in the population or community composition because of an event, be it physical, chemical, or biological. It could also be anthropogenic, like human settlements,
agriculture, air pollution, forest clear-cutting, and mountaintop removal for coal mining
43. Resistance - so many Star Wars references… but actually it’s a measure of how that disturbance can
affect flows of energy and matter in an ecosystem.
44. Resilience - the RATE at which an ecosystem returns to its original state after a disturbance
45. Watershed - all land in a given landscape that drains into a particular stream, river, lake, or wetland
(what that means is, if you pour out a bucket of water onto a grassy area of Lincoln because why
not...eventually that water is going to drain into Lake Lafayette. But if you did the same thing at Godby,
it would drain to Lake Munson)
http://blogs.tallahassee.com/community/wp-content/uploads/2014/02/watershed-map.jpg
46. Restoration ecology - the study and implementation of making damaged ecosystems all better again
47. Intermediate disturbance hypothesis - the hypothesis that ecosystems experiencing intermediate
levels of disturbance are more diverse that those with high or low levels of disturbance. At high levels of
disturbance, population growth rates usually can’t keep up, but when it’s too low, competition is high
and you’ll see the best of the best dominating. Remember, natural disturbances aren’t always bad.
Biomes
1. Terrestrial biome - a geographic region categorized by a particular combination of average annual
temperature, annual precipitation, and distinctive plant growth forms on land.
2. Aquatic biome - an aquatic region characterized by a particular combination of salinity, depth, and
water flow
3. Tundra - a cold and treeless biome with low-growing vegetation. Think Canada, Alaska, Northern
Russia, and Antarctica
4. Permafrost - an impermeable, permanently frozen layer of soil (or at least we want it to stay
frozen…more on this in the climate change unit!)
5. Boreal forest - a forest biome made up of coniferous evergreen trees that can tolerate cold winters
and short growing seasons (Southern Canada, Southern Russia, and parts of Europe)
6. Temperate rainforest - coastal biome typified by moderate temperatures and high precipitation
(Northern Cali to Alaska [redwoods], Southern Chile, east coast of Australia and west coast of New
Zealand)
7. Temperate seasonal forest - warm summers, cold winters, dominated by broadleaf deciduous trees
like beech, maple, oak, hickory, with some coniferous trees too. I found Florida! As well as the
Southeast US and a lot of Europe.
8. Woodland/shrubland - hot, dry summers...mild, rainy winters. Southern Cali (chapparal), Southern
South America, SW Australia, Mediterranean Sea. Drought-resistant shrubs, like yucca, scrub oak, and
sagebrush. Hot and dry = a lot of wildfires, and all of the rain = nutrient poor soil due to leaching
9. Tropical rainforest - warm and wet biome between 20 N and 20 S of the equator, with high
temperatures and high precipitation all year. There is high productivity and high decomposition, and
the most biodiversity of all of the terrestrial biomes.
10. Tropical seasonal forest/savanna - a biome marked by warm temperatures and distinct wet/dry
seasons. Subsaharan Africa is an example… typically you’ll find dense stands of trees and shrubs
surrounded by grasses and scattered deciduous trees
11. Subtropical desert - a biome at 30 N and 30 S with hot temperatures, dry conditions, and sparse
vegetation. Mojave Desert, Sahara Desert, Arabian Desert. Cacti and other succulent plants dominate.
12. Freshwater wetland - an aquatic biome that is submerged or saturated by water for at least part of
the year, but shallow enough to support emergent vegetation (plants that grow out of the water).
Swamps and bogs.
They’re super important to the ecosystem, since they take in large amounts of rainwater and release it
slowly into groundwater and other nearby streams (reducing flood and drought severity)... and
they’re a natural filter for water, removing pollutants so the groundwater can be recharged with
clean water. As much as a third of all endangered bird species live in the wetlands, even though it's
only 5% of the country. But people (!!) have drained over halfs of the wetlands for agriculture,
development, or eliminate mosquito breeding grounds
13. Salt marsh - marsh containing nonwoody emergent vegetation found mostly by estuaries (where the
fresh river water mixes with salty ocean water). With all of the nutrient rich organic material coming
from the ocean, they’re very productive for plants and algae, which in turn filter contaminants.
Important habitat for spawning fish and shellfish.
14. Mangrove swamp - swamp along tropical and subtropical coasts, with salt-tolerant trees whose roots
are submerged in water. These trees protect coastlines from erosion and storm damage, and their
leaves provide nutrients when they fall in the water.
15. Intertidal zone - the narrow band of coastline between the levels of high tide and low tide
16. Coral reef - the most diverse marine biome on Earth, found in warm, shallow waters beyond the
shoreline. Currently in danger from coral bleaching, since the algae inside die due to disease and
warmer, more acidic oceans, and the coral turns white. Unless the algae come back, the coral will die
too.
17. Open ocean - deep ocean water, far from the shorelines, where sunlight cannot reach. Scary.
Evolution & Species Distribution
1. Phylogeny - branching pattern of evolutionary relationships
2. Evolution - a change in the genetic composition of a population over time
3. Microevolution - evolution below the species level, such as the evolution of different varieties of
apples or potatoes
4. Macroevolution - evolution that gives rise to new species, genera, families, class, or phyla.
5. Gene - a physical location on the chromosomes within each cell of an organism
6. Genotype - complete set of genes in an individual
7. Phenotype - a set of traits (anatomy, physiology, behavior) expressed by an individual
8. Mutation - a random change in the genetic code produced by mistake in the copying process. A
random process that is not based in difference in fitness.
9. Recombination - the genetic process by which one chromosome breaks off and attaches to another
during reproductive cell division. It is through mutations and recombinations that genetic diversity is
created, and selective pressures determine the frequency of these genes.
10. Evolution by artificial selection - the process by which humans determine which individuals breed,
typically with a preconceived set of traits in mind. How a wolf gave rise to all dogs, from the St. Bernard
to the chihuahua
11. Evolution by natural selection - the process in which the environment determines which
individuals survive and reproduce.
12. Fitness - not how much an organism works out, but rather a measure of their ability to survive and
reproduce
13. Adaptation - a trait that improves an individual’s fitness
14. Gene flow - the process by which individuals move from one population to another and thereby alter
the genetic composition of both populations
15. Genetic drift - change in the genetic composition of a population over time as a result of random
mating. A random process that is not based in difference in fitness.
16. Bottleneck effect - a reduction in the genetic diversity of a population caused by a reduction in its
size. Could be from habitat loss, a natural disaster, harvesting by humans, or changes in the
environment. A random process that is not based in difference in fitness.
17. Founder effect - a change in the genetic composition of a population as a result of descending from a
small number of colonizing species. A random process that is not based in difference in fitness.
18. Geographic isolation - physical separation of individuals from others of the same species
19. Allopatric isolation - the process of speciation that occurs with geographic isolation
20. Reproductive isolation - the result of two populations within a species evolving separately to the
point that they can no longer interbreed and produce viable offspring
21. Sympatric speciation - the evolution of one species into two, without geographic isolation
22. Range of tolerance - the limits to the abiotic conditions that a species can tolerate.
23. Fundamental niche - the suite of abiotic conditions under which a species CAN survive, grow, and
reproduce
24. Realized niche - the range of abiotic and biotic under which a species actually lives
(so basically, your fundamental niche is all of the jobs you could possibly have with your set of skills
and qualifications, but the realized niche is the job you actually get)
25. Distribution - areas of the world in which a species lives
26. Niche generalist - a species that can live under a wide range of abiotic or biotic conditions. Like a
raccoon.
27. Niche specialist - a species that is specialized to live in a specific habitat or to feed on a small group of
species. Like a Florida panther.
Community Ecology
1. Community ecology - the study of the interactions among species
2. Symbiotic relationship - the relationship between two species that live in close association with each
other, whether it’s nice or mean
3. Competition - struggle between individuals to obtain a shared limiting resource
4. Competitive exclusion principle - the sad fact that two species competing for the same limiting
resource cannot coexist. Someone is going to get the food, and someone gonna die. Life is hard.
5. Resource partitioning - when two species divide a resource based on differences in their behavior or
morphology. Basically a fancy word for sharing. Some examples include birds that feed at different
levels of the tree, maybe 1 species feeds at day while the other feeds at night…
6. Predation - an interaction in which one animal typically kills and consumes another animal.
7. Parasitoid - A type of predator that lays eggs inside other organisms (their “host”). Ewww.
8. Parasitism - an interaction where one organism lives in or on another organism. Examples - dog,
fleas: flea gets food, but dog is miserable
9. Pathogen - a parasite that causes disease in its host
10. Herbivory - eats producers. omnomnom.
11. Mutualism - an interaction between two species that increases the chance of survival or reproduction
for both species. Examples - bee, flower: the bee gets to eat, the flower has its pollen spread; humans,
gut bacteria: human has their food digested completely, bacteria gets food
12. Commensalism - a relationship between two species in which one benefits and the other is “meh”
(scientific term for neither helped nor harmed). This tends to be the most difficult to provide strong
evidence for, since are you absolutely SURE the meh organism isn’t benefiting? Examples - trees, birds: the bird has a cool perch, the tree is whatever about it.
13. Keystone species - a species that plays an extremely important role in the ecosystem even if there
aren’t a lot of them. It gets its name from the keystone brick in an arch… if you take it out, the arch
falls, and similarly, the ecosystem fails without the organism. Examples include beavers, sea stars
14. Ecosystem engineer - a keystone species that creates or maintains habitat for other species.
Examples: beavers (build dams that collect water) and alligators (dig holes)
15. Ecological succession - predictable replacement of one group of species by another group of species
over time
16. Primary succession - ecological succession occurring on surfaces where THERE IS NO SOIL
PRESENT (like after a glacial retreat, newly cooled lava after an eruption, or an abandoned parking lot)
17. Secondary succession - succession of plant life that occurs in areas that have been disturbed BUT
THERE IS STILL SOIL PRESENT (like after a wildfire)
18. Pioneer species - the first organisms to come to an area in horse-drawn covered wagons and make
little settlements, like lichen and moss
19. Theory of island biogeography - there is a relationship between the number & types of different
species on an island and the size of the habitat, as well as distance between the island and mainland. Larger islands tend to support more life, and the smaller distances between island & mainland supports
higher rates of immigration
Diagrams