Sampling pt 2

Question 1

What is a pooter?

Answer 1

used to catch small insects

by sucking on a mouthpiece, insects are drawn into the holding chamber via an inlet tube

filter prevents them from entering the mouth

Question 2

What is a pitfall and sweep nets?

Answer 2

hole in the ground to catch small crawling invertebrates

prepped so the roof does not allow rain water to enter

has to be checked regularly

a net that is used to catch insects in areas of long grass

Question 3

What is tree beating and kick sampling?

Answer 3

tree beating:
takes samples of invertebrates living in a tree or brush
white cloth stretched under a tree
tree is shaken to dislodge the animals

kick sampling:
study organisms lived in the river
river bed is kicked over a certain period of time
a net is held down stream

Question 4

How are plants sampled?

Answer 4

using a quadrat which can also be used to pinpoint an area which the samples should be connected

can also be used for small moving animals such as mussels and barnacle

Question 5

What are the two types of quadrat and what are they used for?

Answer 5

point quadrat:
frame containing a horizontal bar
at set intervals, pins can be pushed through to reach the ground
each species that touches the bar is recorded

frame quadrat:
square frame divided into a grid of equal sections
type and number of organisms in each section of quadrat is recorded

Question 6

How are quadrat frames used?

Answer 6

density:
count number of organisms in quadrat, this gives density per metre squared, this is an estimate

frequency:
used when individual members are hard to count, e.g. grass or moss, using the small grid, count the number of squares where the species is present, give a % for occurrence, e.g. if it is in 9 of 10 squares it has a 90% occurence

% cover:
used when species is abundant but difficult to count
estimate by eye of the area within the quadrat that the plant covers

Question 7

How do quadrat results become more reliable?

Answer 7

measure a different poiint

larger the number of samples taken the more reliable the results

then mean is calculated

then multiply average number of organisms per metre squared by the whole area

Question 8

How are animal population sizes estimated?

Answer 8

capture-mark-release-recapture

time is given to allow organisms to redistribute themselves throughout the habitat

by comparing the number of marked individuals in the second sample to the marked individuals recaptured can be used to estimate the sample size

the greater the number of marked individuals recaptured the smaller the population

Question 9

What are abiotic factors?

Answer 9

non-living conditions in a habitat that have a direct effect on the living organisms that reside there

e.g. light and water available

Question 10

What conditions a measure to draw conclusions about the organisms present and the conditions they need for survival?

Answer 10

wind speed (ms-1), light intensity (lx), relative humidity (mg dm-3),pH, temperature, oxygen content in water (mg dm-3

Question 11

Why are sensors advantageous?

Answer 11

rapid changes detected
human errors reduced
precision can be acheived
data stored and tracked on a computer

Question 12

Why is sampling important in measuring biodiversity of a habitat?

Answer 12

impoossible to count every individual

provides estimate

representative of whole area

Question 13

Outline how a frame quadrat is used to measure biodiversity? How is accuracy improved

Answer 13

use tape measure at right angles
generate random coordinates
determine abundance
sample at different times of year