b4 - community level systems (copy)

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what are 4 examples of materials which are recycled through componenents of an ecosystem

1. water

2. carbon

3. nitrogen

4. oxygen

why is the recycling of nutrients important

if nutrients weren’t recycled they would all get used uo and there wouldn’t be any left for future organisms

describe the steps of the water cycle

1. water from lakes, rivers,oceans and soil evaporates into water vapour and rises into the atmosphere

2. water can also evaporate from plants through a process called transpiration

3. as the water vapour accumulates, it will can condense to form clouds

4. later the water will fall as rain which we call precipitation

5. the water will then seep into the soil , flow into rivers and lakes and be taken up by plants

6. the whole cycle then repeats over and over

in the water cycle what is evaporation

the process by which liquid water (in rivers, lakes etc) becomes gaseous water in the atmosphere

liquid water → gaseous water

in the water cycle what is condensation

the process by which gaseous water in the atmosphere becomes liquid water in clouds

gaseous water → liquid water

in the water cycle what is precipitation

the process by which liquid water falls from clouds as rain

what are the 5 stores of carbon

1. in the air (where its carbon dioxide)

2. in plants

3. in the soil

4. in fossil fuels

5. in animals

describe the steps of the carbon cycle

1. whole thing is powered by photosynthesis where green plants and algae take in the carbon dioxide from the atmosphere to make carbohydrates, fats and proteins

2. can then be passed on to animals by eating plants which passes the carbon compounds along to them

3. c02 is released into the atmosphere by plant and animal respiration

4. plants and animals die and decompose they are broken down by decomposers which release co2 back into the air through respiration

5. plant and animal products (e.g. wood and fossil furls) are burnt (combustion) which releases co2 back into the air

in the carbon cycle whihc process remove carbon dioxide from the atmopshere

photosynthesis

in the carbon cycle which 3 proccesses releease carbon dioxide back itno the atmosphere

2. respiration

3. decomposition

4. combustion

why is the nitrigen cycle important

There's lot of nitrogen in the air – about 78% of the air is nitrogen. Because nitrogen is so unreactive, it cannot be used directly by plants to make protein. Only nitrates are useful to plants, so we are dependent on other processes to convert nitrogen to nitrates in the soil.

how is nitrogen cycled through an ecosystem

• nitrogen is fixed by lightning or nitrogen fixing bacteria

• dentrifying bacteria release nitrogen back into the atmosphere

what are decomposers

microorganisms which break down or decay dead organic material as well as animal waste

what happens during decomposition

nutrients are released back into the soil to be recycled

what are some of the organisms that help in decomposition

bacteria and fungi

what are the three factors affecting decomposition rate

1. temperature

2. water

3. availability of oxygen

how does temperature affect the decomposition rate

Chemical reactions generally work faster in warmer conditions, but if it is too hot the enzymes in the bacteria can denature and stop decomposition.

how does water affect the decomposition rate

• decomposing microorganisms need water for chemical processes

• less water available, the slower these chemical processes will be

how does availability of oxyegn affect the decomposition rate

• decomposers respire aerobically so lack of oxygen forces microorganisms to respire anaerobically

• anaerobic decay is slower and less efficient

why does carbon need to be recycled

because theres only a set amount of carbon in the world

whats a community

the population of different species living in a habitat

whats a population

the number of a particular organism within an area

whats a habitat

a natural home or enviroment of an organism

whats an ecosystem

the interaction of a community of living organisms with the non living parts of the environment

whats distribution

how an organism is spread out in a given area

whats competition

an interaction between organisms or species in which they both try to use the same limited resources.

whats interdependance

idea that all organisms in an ecosystem depend upon one another

whats an abiotic factor

non living parts of an enviroment (e.g. soil PH)

whats a biotic fcator

living parts of an enviroment (e.g. snail)

whats a stable community

the species and environmental factors are in balance so that the population sizes remain fairly constant

what are the abiotic factors affecting communities

1. light intensity

2. temperature

3. moisture levels

4. soil ph and mineral content

how does light intensity affect communities

● Light is required for photosynthesis.

● The rate of photosynthesis affects the rate at which the plant grows.

● Plants can be food sources or shelter for many organisms.

how does temperature affect communities

temperature affects the rate of photosynthesus

how does moisture levels affect communties

Both plants and animals need water to survive

how does soil ph affect communities

Soil pH affects the rate of decay and therefore how fast mineral ions return to soil (which are then taken up by other plants).

what are biotic factors affecting communities

1. food availability

2. new diseases

3. new predators

how does food availability affect communties

more food means organisms can breed more successfully and therefore the population can increase in numbers

how do new predators affect communities

if the number of predatoes decreases, then the number of prey might increase because fewer of them will be eaten

how do new diseases affect communities

when a new pathogen arises the population has no resistance to it so they can be wiped out quickly

what are the 3 types of interdependence

1. mutualism

2. parasitism

3. predation

whats mutualism

when two species can interact and mutually benefit from each other

whats parasitism

rekationship between two organisms where in one organism (the parisite) thrives at the cost of the other (the host)

whats predation

where one organism, the predator, kills and eats another organism, its prey

what are 4 things animals compete for

1. mates

2. space

3. food

4. water

what are 4 things plants compete for

1. light

2. minerals

3. water

4. space

how is a food web different to a food chain

• they are effectively multiple food chains combined

• food webs show all interactions between the species in the community

what are producers

● E.g. plants and algae

● They make their own food by photosynthesis.

what are consumers

organisms that consume other organisms for their energy

what are primary consumers

consumers that eat producers

what is a secondary consumer

organisms that eat primary consumers.

what are tertiary consumers

• organisms that eat secondary consumers

• They have no predators and are at the top of the food chain