Samplings

How to use a quadrat

1) measure out 10m by 10 m grid in your area

2) use a random number generator or dice to pick coordinates

3) place your quadrant at those coordinates

4) count the number of each species in this area

5) Do this 10 times and calculate a mean

What are the 3 different techniques of samplings

Opportunistic

Stratified

Systematic

Opportunistic sampling

Simply using what is readily available to you, very open to bias

Stratified sampling

Breaking down populations into subgroups ( strata ) and then randomly sampling from each group proportional to size

Systematic sampling

A probability sampling method where researchers select members of the population at a regular intervals

How to use transect sampling ?

Lay out a measuring tape for 10 m from fixed point

Take your samples every 1m down this line

This allows you to look at abiotic factors that might affect an environment

It is also very good for looking at habitats like beaches

Sampling animals

Type : Pooter

Used to catch small insects. You suck on a mouthpiece and this draw insects into a holding chamber. Filters stop you getting bugs in you mouth.

Type : Sweep Nets

Used to catch insects in long grass or swamp / marsh territory

Type : Pitfall traps

A hole is dug in the group and small invertebrate fall into it. These are normally deep so the samples cannot escape and they contain a lid so nothing drowns

Tye : tree Beating

Trees are shaken and organism fall out onto a sheet or net placed underneath

Type : Kick sampling

River banks are kicked repeatedly, dislodging any organism , and a net downstream collects them.

What is the definition of abiotic factor ?

abiotic factors are non-living environmental elements that influence the distribution and abundance of organisms within an ecosystem

Examples of abiotic factors ?

Wind speed , Light intensity, relative humidity, pH , temperature , O2 content

What are the sensor used for wind speed + measurement ?

Anemometer m /s -1

What are the sensor used for light intensity + measurement ?

Light meter Lux / lx

What are the sensor used for relative humidity + measurement ?

Humidity sensor mg dm -3

What are the sensor used for pH + measurement ?

pH probe pH

What are the sensor used for temperature + measurement ?

Temperature probe *c

What are the sensor used for oxygen content + measurement ?

Dissolve O2 probe mg dm-3

What is the definition of biotic factors

biotic factors are living components of an ecosystem that influence other organisms within that ecosystem

What are some examples of biotic factors ?

Plant , animals , fungi , bacteria