Ecology - Abundance And Distribution

Question 1

Define uniformly distribution

Answer 1

Occurs when resources are evenly spread or when individual of a specie are hostile to each other

Question 2

Def clumped distribution

Answer 2

Groups of plants or herds of animal depend on specific resource will be in an area where resource located

Question 3

Random distribution

Answer 3

Plenty of resource and no competition

Question 4

Quadrants

Answer 4

Used to sample slow or non mobile organism

Quantitative measuring

Can calculate percentage cover or do individual counts

Question 5

How to do quadrants

Answer 5

1) place 2 tapes measure at right angle to create a graded area to take sample from

2) use a random number generator to generate coordinates to take sample from

3) place quadrants on the coordinates + either count the abundance of the specie or calculate percentage cover

4) repeat at least 30 times

Question 6

Limitation of quadrants

Answer 6

Limitation of sample area

Random ness of the sampling

Decision made about whether to include organism or exclude partly covered by the quadrant

Question 7

Limitation of ACFOR

Answer 7

Is a subjective scale;two ppl will not get the same results

No set definition for terms

Species can be rated to how easily they are spotted not abundant

Question 8

Transect

Answer 8

Systematic sampling

Seta tape between two points record every individual that touches the tape

Question 9

Belt transect

Answer 9

1) tape measure placed through a non uniform ecosystem

2) quadrant placed at intervals along the transect to measure the impact of changes in the environment

Question 10

What do you use to measure the temperature

Answer 10

Glass/digital thermometer

Thermistor

Question 11

What do you use to measure light intensity

Answer 11

Light meters

Question 12

What do you use to measure pH

Answer 12

pH indicators

pH meters

Question 13

What do you use to measure the wind speed

Answer 13

Anemometer

Question 14

What do you use to measure the slope of incline

Answer 14

Clinometer

Question 15

What do you use to measure the oxygen (in water)

Answer 15

Digital oxygen probe

Question 16

Primary succession

Answer 16

1) a pioneer specie colonise bare rock or sand

2) pioneer specie are adapted to survive harsh abiotic conditions and change the abiotic factors to become less harsh through death and decomposition

3) moss and smaller plants can now survive and they further increase depth and nutrients density of the soil as they die

4). This continues and larger plants can survive c further change the environment

5) each new specie May change the environment in a way that th eprevious specie can no longer survive as they become out-competed

6) these changes result in a less hostile environment and increases the biodiversity

7) final stage of succession is a climax community

Question 17

Primary succession step 1

Answer 17

Pioneer specie can withstand harsh conditions and germinate easily
As the pioneer specie die and decompose the dead organic matter forms the soil

Question 18

Primary succession step 2

Answer 18

Seeds of the small plants and grass on this soil begins to grow and adapted to survive in shallow , nutrients poor soil
—> the roots fo these small plants form a network that helps to hold the soil in place and prevent it from being washed away

Question 19

Primary succession step 4

Answer 19

As the small plants die and decompose the soil becomes DEEPER and more nutrients rich

Question 20

Primary succession step 5

Answer 20

Larger trees and shrubs as well as small trees can grow —> require more water and stored in the deeper soil

Question 21

Primary succession step 6

Answer 21

Over time the soil becomes sufficient deep and contains enough nutrients and hold enough water to support the growth of large trees

—> final specie to colonise of new land become the dominant specie of now complex ecosystem—> climax community

Question 22

Define succession

Answer 22

The process by which organism colonising an area change over time

Question 23

Define colonisation

Answer 23

The process by which new specie spread to new area

Question 24

Define pioneer specie

Answer 24

Specie which are first to colonise new or disturbed ecosystem

Question 25

Define climax community

Answer 25

Self sustains community with relatively constant biodiversity and specie range

It is most productive group of organism that a given environment can support long term

Question 26

Define plagioclimax

Answer 26

Climax community that is least in part the result of human intervention

Question 27

How does human prevent climax community from developing

Answer 27

Regular mowing prevents woody plants from establishing themselves in a lawn

The grazing activity of livestock

Question 28

How does the pioneer specie help break down the top surface

Answer 28

Lichens help slowly break apart the top surface of bare rock this fragmented rock along with the dead organic matter left behind when the lichens die and are broken down forms basic soil

Question 29

What does grasses do

Answer 29

Grasses grow roots that stabilise the soil enabling it to hold more moisture and nutrients