ECOLOGY Flashcards
Species
a group of organisms that can interbreed and produce offspring
- have similar physiological and morphological characteristics
- can interbreed to produce fertile offspring
- genetically distinct from other species
- have common phylogeny
Hybrid
when two similar species mate to produce infertile offspring
ecology
study of the relationships between living organisms and their environment
habitat
the environment in which a species normally lives (location of living organism)
population
a group of organisms of the same species who with each other at the same time
community
a group of populations living and interacting with each other at the same time
ecosystem
a community and its abiotic environment
distribution
geographical range of an organism
niche
ecological role and space that an organism fills in its ecosytem
autotroph
an organism that synthesizes its own organic molecules from simpler inorganic substances
- convert light energy into chemical energy
e. g. grass, cyanobacteria, algae
heterotrophs
an organism that obtains organic molecules from other living organisms and their dead remains
e.g. zooplankton, sheep, insects, fish
detritivore
(decomposer/hetereotroph); an organism that obtains organic molecules from detritus by internal digestion
(obtains nutrients by injesting non living matter)
e.g. vultures, earthworms, woodlice
saphotroph
(decomposer/heterotroph); obtain organic nutrients from dead organism by external digestion (secretes enzymes and abosrbs broken down molecules)
e.g. fungi and bacteria
what do decomposers aid in
nutrient recycling
polulation isolation
- populations can be separated from the rest of the species and evolve differently to form a new species
e. g. bodies of water or physical objects can separate species
systematic sampling techniques
- use of a quadrat
-use of transect
(RANDOM SAMPLING) - determine frequency and distribution
Abiotic factors
Abiotic and biotic factors
Abiotic: temperature, light, pH, air humidity, etc
NUTRIENT RECYCLING
Ecosystems recycle carbon, nitrogen and other elements/compounds necessary for life as there aren’t enough mineral needs for all the organisms in the biosphere
Organisms absorb valuable minerals and organic compounds and use them to build their cells
They are gained through feeding and then strorage
Released through excretion, respiration/photosynthesis and decomposition
This recycling makes ecosystems sustainable and productive
examples of nutrient recycling
- nitrogen cycle (nitrogen fixation by bacteria in root nudules; supplied by faeces and urine)
- carbon cycle
DECOMPOSERS:
DECOMPOSERS:
Decay
Decomposers (saprotrophs and detritivores) break down the body part of dead organisms through digestive enzymes that convert the organic matter into usable form
Decomposers recycle nutrients; play a major role in soil formation, which plants need (humus layer of organic debris and nutrients released)
energy origin in food chain
This energy derived from the sunlight, converted to chemical energy by photosynthesis in autogrophs, travels up the food chain in heterotrophs by feeding in an energy flow. As the energy rises up the food chain, loses a tenth of its original energy. HEAT(energy) CANNOT BE RECYCLED
why is biomass restricted in the food chain
Energy is released from carbon compounds by respiration and is used in living organisms and converted to heat
However living organisms cannot convert heat to other forms of energy
The energy losses between trophic levels therefore restrict the length of food chains and biomass of higher trophic levels, meaning that tertiary consumers must consume more than a primary producer to gain energy
90% of sunlight energy goes back into space
Low Carbon Dioxide Levels are a limiting factor photosynthesis
Photosynthesis
light –> chemical energy
6CO2 + 6H2O—> C6H12O6 + 6O2
-energy derived from sunlight and travels up food chain
how is energy lost in the food chain
Energy is lost in a food chain by:
1) Cellular respiration releasing energy as heat
2) Undigested material released as feces since it was not absorbed or assimilated in the body of the organism
3) Death of an organism before it is consumer by an organism in the next trophic level
4) Not all of the organism consumer in the first place as food, abandoned food is left to decayp
CARBON CYCLE + carbon sinks
CARBON CYCLE
Autotrophs convert carbon dioxide into carbohydrates and other compounds, which are then used.
How can we calculate the size of carbon sinks? We can’t because of their fluxes.
cellular respiration
controlled release of energy in organisms from organic compounds to produce ATP
- heat energy used up by energy (cant be recyled)
C6H12O6 + 6O2—> 6CO2 + 6H20+ ATP
pyramids of energy
each energy level is smaller as energy is lost
= 1/10th lost
units of energy
kJ m^-2 yr^-1 (kilojoules per square meter per year)
Methods carbon dioxide is released into environment:
Methods carbon dioxide is released into environment: Breathing Slash and burn Car fuels Oil and gas formations Coal Volcanic activity
carbon and aquatic systems
- contain dissolved carbon dioxide; CARBONIC ACID or hydrogen carbonate ion
- carbonated water has acidic taste
carbon and autotrophs
Carbon dioxide diffuses from the atmosphere or water into autotrophs
Carbon dioxide is produced by respiration, as a byproduct. Autotrophs use carbon dioxide in photosynthesis. CO2 diffuses out of organisms into water or the atmosphere
Methane
- microbes can produce carbon compounds
- archea include methanogens; anaerboic and metabolise food to produce methane as waste gas
- farts of cows
methanogen
produce methane as a metabolic byproduct of anoxic conditions
oxidation of methane
- burning fossil fuesl produces carbon dioxde
- methane main ingrident in nautral gas
CH4 + O2—> CO2 + 2H20
Burning of fossil fuels creates carbon dioxide
Methane is the main ingredient in natural gas fossil fuel
Cycle of creating fossil fuels: thousands of years, burning them: super rapid
Peat as fossile fuel
- peat is organic matter which hasnt completly decomposed because of acidic/anaerobic conditions in waterlogged soils
- soil that forms peat is called histosol
- in order to be used as a fuell; has to be dried out and cut into slaps
- used when oil prices are high
- environmental concerns; preservation of wetlands due ot importance for ecosystem + climate change
oil and gas formation
- Millions of years ago tiny animals lived in the sea
- When they died they fell into mud and sand at the bottom of the sea but didn’t rot away
- Over millions of years, the animal remains were buried deeper by the mud and sand
- The temperature and pressure changed the mud and sand into rock and the dead animals into oil and gas
COAL FORMATION:
COAL FORMATION:
- About 300 million years ago, the Earth was covered in lots of vegetations
- Dead plants fell into swampy water and the mud prevented them from rotting away
- Over the years, the mud piled up and squashed the plant remains
- After millions of years under pressure, the mud became rock and the plants became coal
FOSSILIZATION:
FOSSILIZATION:
- Tree samp (ember)
- Sediment actively deposited
- Permineralization
- Lime state rock
- Animals such as reef building corals and molluscs have hard parts that are composed of calcium carbonate and can become fossilized in limestone
limestone
- maring eoganisms take dissolved carbon out fo water and use it to make carbonate shells
- calcium carbonate reefs formed 9limestoe)
- molluscs use calcium carbonate for their shells
- acidic water degrades calcium carbonate in climate change
The Greenhouse Gases:
The Greenhouse Gases:
Carbon dioxide and water vapour are the most significant greenhouses gases, whereas other gases such as methane, nitrogen oxides and sulfur oxides have less impact
Only when sunlight hits an object does it transform to heat energy (infrared energy)
Greenhouses gases therefore trap heat within the atmosphere; temperature within is warmer
Greenhouse glass used as a model for atmosphere
GH’s have the ability to absorb and radiate infrared radiation; absorb heat from warmed surface and re-radiating it in all directions
The Greenhouse Gases and light/ heat trapping ability
Only when sunlight hits an object does it transform to heat energy (infrared energy)
Greenhouses gases therefore trap heat within the atmosphere; temperature within is warmer
Greenhouse glass used as a model for atmosphere
GH’s have the ability to absorb and radiate infrared radiation; absorb heat from warmed surface and re-radiating it in all directions
The atmosphere:
The atmosphere:
Atmosphere plays a vital role in regulating the temperature of the earth’s surface. It acts as a blanket; keeping us warm at night and sheltering us from heat during the day.
green house gas ability
Ability of a gas depends on its ability to absorb long, wave radiation as well as its concentration in the atmosphere
methane GHG ability
Methane: greater potential to warm planet than carbon dioxide, however it has a short lifetime of 12 years in atmosphere, as it can be broken down into other molecules
Carbon Dioxide GHG ability
Carbon Dioxide: Has an atmosphere lifetime of 50-200 years in atmosphere as it isn’t reactive
CO2 levels have increased by 40% since 1750 and methane has increased 150%
However concentration of C02 is 200x greater than methane
Nitrogen Oxide GHG ability
Nitrogen Oxides: ⅕ concentration of methane, global warming potential is 100x greater than CO2, but their atmospheric concentration is 1000x smaller than CO2 levels
ability of a surface to reflect light
albedo; light colored objects have high albedo
issues with albedo and climate change
- as we have more dark colored objects (dark concrete) who have low albedo earth is absorbing more heat + warming up
How Greenhouse gases heat the atmosphere:
How Greenhouse gases heat the atmosphere:
They absorb and retain heat/infrared radiation
They also filter out UV radiation
Filter out sunlight
GLOBAL CLIMATE CHANGE & GREENHOUSE GASES:
Climate change affects the patterns of temperature and precipitation that occur over a long period of time
Weather can change from hour to hour; climate occurs over thousands of years
It was cold a long time ago; told by proxy data
Factors of global temperature changes:
Volcanic activity Particles suspended in air Sun radiation Positions of continents Oscillations in ocean currents Fluctuations in earth's orbit Inclination of axis Presence of greenhouse gases
industrial revolution + climate change
Onset of industrial revolution brought increase of greenhouse gases; processing of fossil fuels and agriculture (cows)
increases in combustion of fossilized organic matter
Increase of Atmospheric CO2: increases in combustion of fossilized organic matter
Gases produced by human activity #1 carbon emission: human activity such as transport, deforestation, heating homes, meat industry
Methane produced by anaerobic microorganisms in people’s animals: mass consumption of meat= a lot of cattle
Nitrogen oxides released as a result of burning fossil fuels, using organic and commercial fertilizers to help crops grow better
Industrial processes
Coral Reef Threats
Through eutrophication (ocean acidity increased) coral bleaching is being caused
Water temperature and water depth also affects it
Ocean acidification: deaths of algae and corals; loss of habitat
Water temperature: can kill, e.g. manatee who are warm water dependent
precautionary principle
- lower GHG transmission to avoid climate change
- preventative action should be taken to reduce carbon emmiions and GHG
- whotse who wish to continue producing excess GHG should prove there are no harmful effects before continuiing
response;
- farmers/manufacteres/transport prodivdes should invest in new, ‘greener’ techniques that aren’t harmful to environment
- ecologically mindful
- fixing cc issues more expensive than lowering co2 emmisions
why are humans alarmed by current climate change
- while global temperature fluctuations are natural; scientists are alarmed because fluctations are happening are a super fast rate that can’t be explained by natural phenonema
- as a result of fossil fuels/ghgs
nitrogen oxides are produced by
- burning fossil fuels and using catalytic convertes in exhaust systems
- using organic and commerical fertilizers in crops
- industrial proccesses (production of nitiric acid)
climate change as a result of human activity; PRO
- evidence for tempreature rise since industrial revolution
- increase in weather events
- CO2 emiision directly correlated to human activitu
- magnitude/speed of change
- fixing CC is costly
- climatology is complex
climate change as a result of human activity; CON
- disagreements within scientific communitu
- past fluctuations
- natural/theory
- reducing CO2 levels has economic effect
- tempereature isnt increasing as a result of human activity
trophic levels
- producers
- consumers
- decomposers
mecocosm
all/part of an ecosystem enclosed where conditions can be indepednetly changed/controlled
population growth
-sigmoid population curve
preveentative example of GHG
CFC in refrigerators; switch to different chemical
