What does distribution and abundance refer to
distribution refers to the way in which species are spread in an environment
abundance refers to the total number of a particular species in an area
what determines the distribution and abundance of organisms?
abiotic ( non-living: light intensity, water/ moisture levels, oxygen and temperature) and biotic (living: predators, food availability, diseases, competition, parasitism) factors determine the distribution of organisms.
give definitions and examples of abiotic and biotic factors
abiotic factors are non living and include: light, moisture levels, temperature and oxygen levels
biotic factors are living and include: predators, availability of food, diseases and parasitism)
what is meant by the term niche
The unique and specific role and function an
organism plays in an environment
what is the niece concept
Only one organism can occupy each niche in a given habitat at a given time, if two or more species have a niche that overlaps than the best adapted will out compete the other in surviving and reproducing
ecological succession meanaing
gradual changes in an ecoysystem overtime, gradual process where an ecosystem changes over time, as different plant and animal species replace each other in a specific sequence, eventually leading to a more complex and stable climax community
primary succession meaning
an ecological process where life gradually colonizes a new, barren environment, such as newly formed rock from volcanic eruptions or a dried lakebed, with no initial soil or life
give some examples of pioneer species
moss, lichens
pioneer species definition
first organisms that colonise a barren undisturbed habitat during ecological succession
they are organisms designed to survive in harsh conditions (where other species would not survive)
Explain the process of primary succession
the BARREN area is first colonised by PIONEER SPECIES such as MOSSES or LINCHENS which are adapted to survive in extremely HARSH CONDITIONS.
these species then penetrate and begin to BREAK DOWN ROCK
as these organisms DIE the are DECOMPOSE by microorganisms creating a substance called humus which is an organic component of soil
this leads to the FORMATION OF SOIL which makes the environment more suitable for MORE COMPLEX ORGANISMS
as more organism DIE and DECOMPOSE over time the soil becomes more richer in NUTIRIENTS and MINERALS
this enables LARGER and more VARIED and PRODUCTIVE plant species to survive such as SHRUBS.
eventually a CLIMAX COMMUNITY is established- this is the most self sustaining, PRODUCTIVE and STABLE community of organisms which the environment can support
Secondary succession definiton
this occurs in existing soil without any vegetation. this may occur after an event like a forest fire.
the process of ecological recovery that takes place in an area after a disturbance, like a fire or deforestation, has occurred in a previously colonised ecosystem leading to a climax community once again.
what is meant by the Net Primary Productivity?
NPP is the biomass accumulated by plants after respiration. NPP= GPP-R
Plants are autotrops so dont neet to account for energy lost form waste and urination because they dont do that. they photosyntehsize
what is meant by Gross Primary Productivity (GPP)
The total amount of energy captured by plants from sunlight through photosynthesis.
It represents the total energy captured by primary producers before respiration is accounted for.
how do you calculate the NPP
Subtract the GPP from respiration to get the NPP. this is because respiration is the energy that plants use for their own metabolic processes such as prdcutio of ATP
Respiration uses some of the glucose for energy, which means less glucose is available to be converted into plant biomass (like cellulose, starch, proteins, and fats).
what is the energy lost at each trophic level due to
undigested matter
respiration ( exothermic, transfers like thermal energy to the surrounding)
metabolic waste products like urea
what are tropic levels
a trophic level refers to an organism’s position in a food chain or food web, indicating its source of food and the flow of energy through an ecosystem
what is meant by global warming
Gradual increase in the average temperature of the earths atmosphere and surface which can be due to deforestation, burning of fossil fuels, increased agricultural practices (cow farming)
what is the evidence for climate change ?
Records of carbon dioxide levels - increasing levels of carbon dioxide in the atmosphere are believed to contribute towards climate change as C02 is a green house gas and involved in the green house effect
Temperature records - this enables analysis of changes in temperature
CO2 levels in ice cores
pollen in peat bogs - pollen grains are preserved in peat bogs and analysis of samples can give an indication of what type of plants were present at the time when peat bods were formed.
Dendrochronology - is the study of tree rings and the size of tree rings is determined by the temperature
process of Green house effect
Short wavelength UV radiation from the sun passes through the earths atmosphere and is reflected from the earths surface.
These reflected waves are of a longer wavelength (infrared radiation) and are trapped by gasses such as C02 and methane thus leading to an increase in the temperature of the earths surface and atmosphere
What are the effects of climate change
Changes in rainfall patterns and seasonal cycles - lead to migration and animals under threat due to changes to habitat conditions
Changes in the distribution of species - species may move to cooler areas ie northwards. this could potentially lead to extinction of some species due to competition.
Changes to development - sex of many reptiles is determined by the temperature therefore an increase in temperature would have an effect on sex ration possibly leading to some extinction
Disrupted life cycles
polar ice and glaciers retreating, sea levels rising,
why is it good to know the carbon cycle
knowledge of it can help humans make decisions to reduce the levels of green house gasses in the atmosphere
how can climate change be reduced/ reversed
reforestation
sustainable/ renewable sources of energy
what is the equation of Q10
it is much smeller than looks
R refers to the rate of reaction ( could be indicated by oxygen production, by respiration etc)
and the T refers to the temperature.
so you divide rate 2 (bigger rate) by rate 1 ( smaller rate) in order to get figure than put that to the power or ten over temperature 2 (higher temp) minus temperature one (lower temp)
what is the meaning of Q10 coefficient
what happens to the rate of reaction when you increase the temperature by 10 degrees c.
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