Unit 3: (Ch. 27-28) Flashcards
what is an ecosystem?
consists of **all organisms in a community **and the abiotic factors they interact with
what does ecosystem ecology study?
living and nonliving components within an environment, also how natural and human-induced changes affect how they function
what are the 2 ecosystem dynamics involved?
energy flow
nutrient cycling
what is energy flow?
how radiant energy enter an ecosystem and is stored/transferred as a chemical energy
what is nutrient cycling?
describes how certain atoms like nitrogen, carbon, sulfur.. are important for bio proceses
what is the saying for energy flow and nutrient cycling?
energy flows through ecosystems while matter cycles within them
how does energy enter?
as light
energy and nutrients pass from ** –> ** then to ***
primary producers (autotrophs) to primary consumers (herbivores) then to secondary consumers (carnivores)
what connects all trophic levels?
decomposers
what does bacteria and fungi do?
recycle essential chemical elements by decomposing organic material and returning elements to inorganic reservoirs
what are detritivores?
they consume daed or decaying material by ingesting and digesting. They create feces which is then decomposed by decomposers like bacteria and fungi
are decomposers the same as detritivores?
no, the decomposers recycle and decompose the shit that detritivores create
what is the energy flow through an ecosystem?
1st trophic level= producers (like plants)
2nd trophic level = primary consumers (herbivores like a mouse)
3rd trophic level= secondary consumers (carnivores like a snake)
4th trophic level= tertiary consumers (2nd level carnivores like an eagle)
DECOMPOSERS =consume daed or decaying organic material and recycle it back to the 1st trophic level
what is primary production ?
the amount of energy converted into usable chemical energy and thus, biomass (renewable organic material that comes from plants and animals) by the autotrophs (organisms that create their own food) in a given period of time
what is secondary production?
the amount of energy in a consumer’s food that is converted into their own new biomass in a given period of time
how much do herbivores generally consume of the primary production?
1/16th of primary production
do herbivores digest everything that they eat?
no, undigested material is excreted as feces
how do we measure production efficiency?
energy transformers
what is the formula for production efficiency?
P.E = (Net secondary production/Assimilation of primary production) x100%
what is net secondary production?
energy stored in biomass represented by growth and reproduction
what is assimilation of primary production?
total energy in by the organism and excludes the energy lost as feces
what percentage of production efficiency do insects and microorganisms have?
40% or more
what percentage of production efficicnecy do fish have and what are they called?
10% and ectotherms
what percentage of production efficinecy do endotherms have and what is an example of them?
birds and mammals have a 1-3% production efficiency
what is trophic efficiency?
percentage of production transferred from 1 trophic level to the next
is the trophic levels more or less than production efficiencies?
less because they not only take into account the energy lost through respriation but also energy contained in feces
what must nutrients do in an ecosystem?
cycle between abiotic and biotic parts of the ecosystem
what is the most important nutrient in nutrient cycling?
carbon
why is carbon so important?
it forms the framework of the organic molecules essential to all life
how is carbon fixed or converted into usable compounds?
begins as photosynthetic organisms convert CO2 into organic molecules and used by heterotrophs in consumption
what is a carbon sink?
natural or artificial reservoir that accumulates and stores carbon-containing chemicals.
primary producers are all important cause they convert atmospheric CO2 into biomass
how much do primary producers convert CO2 into biomass?
123 GtC
how much does the ocean store carbon CO2?
92 GtC
what is a carbon source?
any process that releases carbon into the atmosphere
what are the most important carbon sources?
respiration (land and ocean), deforestation and
fossil fuel use
do we store more carbon than we release?
no we release more carbon than we store
What is Anthropocene?
geological era we call because of global environment change
human activity stressors that subject ecosystems?
habitat loss and degredation
ozone depletion
chemical pollution
nutrient enrichment
climate change
what are aquatic pollutants?
petroleum products
fertilizers
chlorinated solvents
pesticides
herbicides
intesecticides
polychlorinated biphenyls (PCB’s)
what are soil pollutants?
lead
mercury
arsenic
polyaromatic hydrocarbons
pesticides
herbicides
insecticides
what is a big problem about the pollution we produce?
they persist for a long time and do not biodegrade making them concentrated in the tissues of organisms in higher trophic levels
biological magnification is?
process whereby toxins become increasignly more concentrated in tissues or organisms that make up higher trophic levels and as a result, the biomas is lower
what is an example of biomagnification?
PCB’s in a great lakes food web:
seagulls lay eggs with PCB levels 5000x greater than phytoplankton
Basically as the PCB’s are placed in the water, the phytoplankton takes that in, then its transfered to the next trophic level when the larger fish like trout consume the phytoplankton, then when the seagulls eat the trout, the concentration of PCB’s will be so much higher because of biomagnification.
as the PCB’s are transferred through trophic levels, the concentration of toxins increases.
what are fertilizers used for?
boost primary production to feed a growing population like grass
if excessive fertilizing use occurs, what can emerge from it?
eutrophication
what is eutrophication?
excess fertilizers or any jutrient richness end up in waterways and cause algal blooms
what is the result of eutrophication?
cause the proliferation of plants and algae
agal blooms prevent light from penetrating to deeper levels and plants then die creating anoxic condition where no life can survive
what is climate?
pattern and variation of..
temp
relative humidity
atmospheric pressure
wind
precipitation
atmospheric particulates (think china air)
what is the difference between climate and weather?
climate= long term pattern of weather in a particular area
weather= short term conditions of these variables in a given region
what is paleoclimatology?
study of ancient climates
what is climate change?
significant and lasting change in statistical distribution of weather patterns over periods ranging from decades to millions of years
what is anthropogenic climate change?
change of climate associated with production of greenhouse gases emitted by human activity
what is the change in temperature?
warming temps over the past 100 years
what does the warm climates influence?
levels of precipitation and air pressures impacting more frequent and intense weather events
what would be the immediate cause of climate change?
TSI
total irradiance of the sun
this has not happened yet
Milankovitch cycles have everything to do with climate change right?
no, the earth rotating around the sun acts much too slowly to explain current climate fluctuations
do volcanoes have an affect on climate change?
no, volcanic eruptions would have brought slight cooling but not warm weather weve been experiencing
CO2 output is 0.13 GG
anthropogenic CO2 output is 35 GG
what are the causes of Climate change?
CO2 is primary greenhouse gas emitted through human activity
what is a greenhouse gas?
atmospheric gas that absorbs and emits radiation within thermal infrared range
what are the major greenhouse gases?
water vapour
CO2
CH4
N2O
O3
CFC’s and HCFC’s
what is the greenhouse effect?
1-sun omits energy and earth surface absorbs it, heating it up
2-earth then radiates some of the heat back into atosphere in form of infrared radiation
3-greenhouse gases in atmoshere like CO2 take in infrared radiation and refelect it back to the earths surface
4-trapped energy from greenhouse gases warm up the earth surface
but humans have created too much CO2 through fossil fuels so its heating up the earth too much creating an imbalance in climate change
what physical changes does climate change produce?
increase in ambient temp
changes in annual seasonal precipitation
sea-levels rise
ocean acidification
increased frequency of extreme weather events
recall species range? what sets the limits on species range?
other physical factors like temp and water availability
what is the temp that a species cannot tolerate?
no temp lower than 27 degrees celsius
is species is heat tolerant and cold intolerant where will its range be?
range expands northerly and southern limit stays the same
if species is heat and cold intolerant, where will its range be?
range expands northerly but southern limit also moves northerly
so basically which range will be bigger if the species range for 1 is heat-tolerant and cold intolerant and the other is heat and cold intolerant?
the heat tolrant and cold intolerant
what is phenology?
study of reccuring life cycle traits influenced by abiotic factors like environmental conditions but an emphasis on seasonal changes
what is phenological shift?
change in an organism’s life cycle traits due to changes in environmental conditions caused by climate change
why is phenological shift important?
because say these specific apples are growing at a specific time for these flies to eat, and then they start growing at a different time because of climate change, the flies are fucked
