Biodiversity and ecological surveying
Using quadrats and transects,
measuring the abundance and distribution of organisms - plants or animals - data calculations, how to use a key
and draw a kite diagram, use of indicator species - investigating pollution -
monitoring abiotic factors
Doc Brown's biology exam revision study notes
This page will help you answer questions
such as ...
What is a quadrat? How do
you do a quadrat survey? How do you do calculations from quadrat
measurements? What is a transect? How do you do
a survey using a transect? What are indicator species? How do you draw kite
diagrams? How to use an identification key
Sub-index for this
section on biodiversity and ecological surveying
(1)
Introduction
to investigating distribution and abundance
(2)
Surveying using quadrats and example of quadrat calculations based on
sampling data
(3)
Surveying using transects
(4)
Estimating the percentage cover (distribution) of a species from a quadrat
(5)
Estimating a population size by using a capture-recapture technique
and three ways of trapping animals
(6)
Kite diagrams to show abundance and distribution of
organisms and graphs representing biodiversity-/ecology data
(7)
Using keys to identify organisms
(8)
Monitoring techniques, instruments for measuring abiotic
factors - pollution, living organisms as indicators of environmental changes
- indicator species
(9)
Practical work you
may have encountered and learning objectives
See also
Ecosystems - biotic & abiotic factors - interactions between organisms
- interdependency
Food chains, food webs, trophic
levels, pyramids of numbers or biomass, transfer efficiency
Biodiversity, land management, waste management,
maintaining ecosystems - conservation
TOP OF PAGE and
sub-index on ecology surveys
(9)
Practical work you may have encountered and learning objectives for this
page
Learning objectives
-
Know that living organisms form
communities, and we need to understand the relationships within and between
these communities.
-
Know that these relationships are affected
by external influences.
-
You should be able to use your
skills, knowledge and understanding to:
-
suggest reasons for the
distribution of living organisms in a particular habitat,
-
evaluate methods
used to collect environmental data, and consider the validity of the method
and the reproducibility of the data as evidence for environmental change,
-
at the end of an investigation
and analysis, can you distinguish whether differences in distributions of an
organism are due to one or more environmental factors?
-
is it possible to control, or
allow for, different environmental factors?
-
and you should understand:
-
the terms mean (average
of all of a data set), median (middle value in a data set) and mode
(the most common value in a data set - could be more than one value)
-
that sample size is related to
both validity and reproducibility,
-
the larger the sample, random
sampling from many locations and the more times the experiment is repeated,
the more reliable will be the final analysis and conclusions,
-
reproducibility is the key to a
successful valid investigation,
-
Know and understand the physical factors that may
affect an organism in its habitat (area where the organism lives):
-
To study the distribution of a
species of animal or plant you must measure the population of the organism
in different sample areas.
-
A habitat is where an organism
lives (plant or animal) and its distribution is the areas where the
organisms live an this may depend on environmental factors such as ...
-
ambient temperature,
-
availability of nutrients in the
soil or water,
-
amount of
light falling on the habitat,
-
availability of water in soil
for plants,
-
availability of oxygen and carbon dioxide
in the air or water.
-
Organisms will be adapted by
evolution to fill a niche in a particular area of the environment,
-
but if there is a change in any
of the factors above, then organism populations will be affected, some will
increase and some will decrease,
-
in extreme cases, one species
might die out in an area and another species may take advantage and move in.
-
An organism will be more common
in an area, where environmental factors make conditions more suitable for
the organism to survive and reproduce e.g.
-
shade for plants that need
little sunlight, or out in the open for plants that need bright sunlight,
-
some creatures may prefer damp
conditions, others adapted to dry conditions,
-
greater density/availability of
the organism's specific food requirements
-
Know and understand that quantitative data on the
distribution of organisms can be obtained by:
-
(i) random sampling with
quadrats to cover a large area without sampling all of it
-
A sampling quadrat is usually a
1m x 1m (1 m2) square frame of wood or plastic,
-
Therefore if you measure the
number of organisms in a quadrat you get the density in organisms per square
metre.
-
You can average the random
individual quadrat results to get the mean value for a particular organism/m2.
-
To work out the total population
of an organism in the area you have been randomly sampling, you multiply the
mean by the total area.
-
The more samples you take, the
more reliable is your data, and therefore any deductions made will also be
more reliable, but the data is only statistical, never completely precise,
but
-
In presenting data make sure you
know how to use the terms mean (average
of all of a data set), median (middle value in a data set) and mode
(the most common value in a data set - could be more than one value).
-
(ii) sampling with quadrats along a
linear transect to look for changes across an area of land e.g. to see how a
population changes across a wider area.
-
Note (iii) Whatever field work
you do, the only really reliable data, are data that are consistent, i.e.
always show the same pattern of organism distribution (plant or animal), and
in that way the data is repeatable and reproducible.
-
This involves random sampling
with samples using many quadrats and transects.
-
Does the data support the
question posed about organism distribution?
-
Are differences in population
due to environmental factors?
-
What are the variables?
-
Have the variables been
controlled properly in your survey design?
WHERE
NEXT?
ALL my Biology Notes
Find your GCSE
science course for more help links to revision notes
Use your
mobile phone or ipad etc. in 'landscape' mode
This is a BIG
website, you need to take time to explore it [Website Search
Box]
email doc
brown - comments - query?
HOME PAGE of Doc Brown's Science
UK KS3 Science Quizzes for
students aged ~11-14, ~US grades 6 to 8
Biology * Chemistry
* Physics notes for GCSE/IGCSE
students aged ~14-16, ~US grades 9 to 10
Advanced Level pre-university Chemistry
revision notes for students aged ~16-18 ~US grades 11 to 12
TOP OF PAGE and
sub-index on ecology surveys
Keywords for gcse biology revision notes on ecological surveying
quadrats transects: GCSE 9-1 biology biological science IGCSE
biology revision
notes ecological surveying quadrats transects KS4 biology Science notes on
ecological surveying quadrats transects GCSE biology guide
notes on ecological surveying quadrats transects for schools colleges academies science course tutors images
pictures diagrams for ecological surveying quadrats transects science revision notes on
ecological surveying quadrats transects for revising biology modules biology topics notes to help on understanding of
ecological surveying quadrats transects university courses in biological science
careers in science biology jobs in the pharmaceutical industry
biological laboratory assistant
apprenticeships technical internships in biology USA US grade 8 grade 9 grade10 AQA
GCSE 9-1 biology science notes on ecological surveying quadrats
transects GCSE
notes on ecological surveying quadrats transects Edexcel GCSE 9-1
biology science notes on ecological surveying quadrats transects for OCR GCSE 9-1 21st century biology science
notes on ecological surveying quadrats transects OCR GCSE
9-1 Gateway
biology science
notes on ecological surveying quadrats transects WJEC gcse
science CCEA/CEA gcse science gcse biology revision notes on ecological
surveying quadrats transects

|
 |
 |
 |
 |
 |
 |
 |
 |
 |
 |
 |
 |
 |
 |
 |
Website content © Dr
Phil Brown 2000+. All copyrights reserved on revision notes, images,
quizzes, worksheets etc. Copying of website material is NOT
permitted. Exam revision summaries & references to science course specifications
are unofficial. |
|