Field work
important
ecology
component
in
studying
enables us to find out the numbers and
species of plants and animals living in a
community and to gain information
about the ecological interactions there
the emphasis is on investigation rather
than collecting samples
19.10 Study of local habitats
Safety and ethical
guidelines on field
study
19.10 Study of local habitats
Dos
1. Before setting out, listen to the weather
forecast and wear suitable clothing. Go
through a personal checklist and an
equipment checklist. Bring enough water
and some food. Prepare a journey plan
and let others know where you are going
and the time you are expecting to return
home.
19.10 Study of local habitats
Dos
2. Follow existing paths. Repeated trampling
of areas other than paths can be harmful
to the ecosystem and can prevent the
regeneration of vegetation which may
result in soil erosion.
3. Bring a pen and a notebook. Observation
and good data records are the keys for
successful field studies.
19.10 Study of local habitats
Don’ts
1. Litter – take home all your rubbish or
dispose of it properly in litter bins. Plastic
bottles and plastic bags are reusable
containers, so please reuse them if
possible. Remember the 3R-principles for
treating litter: Reduce, Reuse and
Recycle.
2. Light fires – fire is destructive to the
ecosystems, and may threaten your own
life.
19.10 Study of local habitats
Don’ts
3. Harm any wildlife – each creature,
however small, has a role in the
ecosystem and should be respected. Do
not kill insects or snake just because of
their unpleasant appearance. It is illegal
to kill or wilfully disturb any living
organisms inside country parks or special
areas.
19.10 Study of local habitats
Don’ts
3. Do not collect anything from the
countryside without permission. If you
come across injured wildlife, report it to
the
Agriculture,
Fisheries
and
Conservation Department or the Kadoorie
Farm & Botanic Garden.
19.10 Study of local habitats
Don’ts
4. Interfere with natural structures that are
made by wildlife – spiders’ webs, termite
mounds, birds’ nests are parts of the
ecosystem and are essential for the
survival of these animals (e.g. most birds
cannot breed without nests).
19.10 Study of local habitats
Distribution and
abundance of
organisms
19.10 Study of local habitats
Sampling
the study of a defined area (e.g. a habitat)
by studying parts of the area
take several samples from a habitat,
making the assumption that these
samples are unbiased and representative
of the habitat
to ensure that the samples are unbiased,
they are selected randomly  random
sampling
19.10 Study of local habitats
Sampling using a quadrat
one of the simplest
ways of sampling a
habitat
a quadrat: a square
frame made of wood
or metal
19.10 Study of local habitats
 A quadrat
Sampling using quadrats
to use the quadrat…




Generate a random coordinates of the
site
put the quadrat at the random location
Count the plants and animals inside it,
ignore anything outside the quadrat
repeat the process again in different
parts of the field
19.10 Study of local habitats
Sampling using quadrats
to use the quadrat…

calculate the average number of
individuals per unit square for each
species and measure the area of the
habitat under study to estimate the
density of each speices
19.10 Study of local habitats
Sampling using quadrats
limitations


it will be hard to count fast-moving
animals, this method is limited to
vegetation
and
slow-moving
or
stationary animals
the quadrat must also be placed on a
fairly flat piece of land
Activity 19.5
19.10 Study of local habitats
Sampling using a line transect
this method is used to record exactly
where each species or type of organism is
found
a line transect can be made from a string
marked at regular intervals
 it is stretched across the habitat you
want to examine
 all the organisms touching the string
are recorded with their distance from
one end of the line called the ‘origin’
19.10 Study of local habitats
Sampling using a line transect
 How to make a line transect, and illustrate the
results with a profile diagram
regular internal
marks
stake
line transect
origin
graph paper
height
(m)
soil
1m
0
1
19.10 Study of local habitats
2
3
4
5
distance from origin (m)
6
7
8
Sampling using belt transects
a better method than line transect
belt transect is made by:
 laying out two parallel strings, perhaps
one metre or less apart and record the
plants between them
 or placing quadrats continuously or in
regular intervals along a transect line
Quadrat 1 Quadrat 2 Quadrat 3 Quadrat 4 Quadrat 5
1m
19.10 Study of local habitats
 A belt
transect
Sampling using belt transects
the distribution and relative abundance of
different species along the belt transect
can be studied
the results can be represented by a ‘kite’
diagram or histogram
19.10 Study of local habitats
Sampling using belt transects
kite diagrams
histograms
species 4
species 3
species 2
species 1
Distance along transect line (m)
Think about
19.10 Study of local habitats
Percentage cover
Percentage cover
species 4
species 3
species 2
species 1
Distance along transect line (m)
Measurement of
abiotic factors
19.10 Study of local habitats
Common instruments for
measuring abiotic factors
Light intensity
pH
Air movement
 Light meter
 pH meter
 Anemometer
19.10 Study of local habitats
Common instruments for
measuring abiotic factors
Temperature
 Electronic
thermometer
Dissolved oxgen
 pH meter
19.10 Study of local habitats
Humidity
Salinity
 Thermohygrometer
 Refractometer
Field study
19.10 Study of local habitats
Field study 1
Studying a woodland
Woodland is one of the three major types of
vegetation in Hong Kong (the other two are
grassland and scrubland). Most ecological
processes, such as energy flow, materials
cycling, effects of human impacts,
relationships between organisms and
adaptations, are available in woodland.
19.10 Study of local habitats
In this study, identification of all
encountered animals and plants to species
level is not necessary. Identify to species
level only for those important species. For
others, use common names or assign
number to different species such as tree 1,
shrub 1, shrub 2, spider 1 and so on. On
the other hand, vary accurate data and a
very large sample size is not necessary.
19.10 Study of local habitats
A. Aims of studying the
organisms on a slope
living
1. To understand the composition of a
woodland.
2. To measure and record the abiotic
factors that affect life.
3. To examine how organisms are adapted
to the environment.
4. To investigate any interrelationships
among living organisms in the habitat.
19.10 Study of local habitats
5. To investigate how biotic and abiotic
factors are related to each other, and
how
abiotic
factors
affect
the
distribution
and
abundance
of
organisms.
19.10 Study of local habitats
B. Precautions
1. Wear trousers and long-sleeved shirts.
2. Beware of swarm of wasps, bees and
snakes. Do not irritate hives of wasps,
bees or other wild animals.
3. Impose minimum disturbance to the
woodland. Collect samples only when
necessary. Whenever possible, identify
the organisms in the field, or you may
take photographs and identify them
later.
19.10 Study of local habitats
4. Wear gloves when collecting litter to
protect your hands from certain
invertebrates such as centipede.
19.10 Study of local habitats
C. Equipment (per group)
Transect line
1
Quadrat (50 x 50 cm)
Air net
Light meter
Plastic bags
Digital camera
Sorting tray (white)
Anemometer
Labels
Calculator
Evaporating dish
19.10 Study of local habitats
Measuring tape
1
1 Ranging poles with spirit
1 level thermometer
1 Compass
5 Forceps
1 Beakers (100 cm3)
1 Digital hygrometer
1 Spade
Protractor
1 pH paper
1 Sieves
1
1
2
2
1
1
1
D. Procedures
Field work
1. Walk around and examine the habitat.
Draw a sketch map of the woodland
showing the location of the studied site.
2. Run a 20 m transect line across the
area which can represent the woodland.
3. Along the transect line, measure the
gradient of the slope at 2 m intervals.
Use the results to draw a profile
diagram.
19.10 Study of local habitats
4. Select a suitable area of ground that is
representative. Put a quadrat (50 x 50 cm)
on the area.
5. Use the air net to catch flying animals
near the transect line. Search for small
animals in different micro-habitats such
as under or inside a rotten log, on leaf
surfaces, in flowers or in fruits etc.
Whenever possible, identify and count the
animals in the field (or you may take
photographs). Presence of spider web and
animal damage on leaves may provide
useful information of animal distribution.
Free the animals after the identification.
19.10 Study of local habitats
6. Collect all the litter within the quadrat and
put it into a plastic bag with labels. Bring it
back to school for further investigation.
7. Measure the abiotic factors:
(a) Use the light meter to measure the
light intensity
(i) above canopy layer (you can
measure this at open space
outside the woodland),
(ii) below the canopy layer but above
the shrub layer, and
(iii) below shrub layer.
19.10 Study of local habitats
(b) Use the thermometer to measure the
temperature
(i) on the surface of litter layer,
(ii) in open air within the woodland, and
(iii) in open air outside the woodland.
(c) Use the digital hygrometer to measure the
humidity
(i) on the surface of litter layer,
(ii) in open air within the woodland, and
(iii) in open air outside the woodland.
19.10 Study of local habitats
(d) Use the anemometer to measure the
average wind speed inside and
outside the woodland.
8. Use a spade to dig up the top 5 cm of soil
within the quadrat. Place the soil on the
sorting tray and sort out the animals for
identification.
9. Collect about 1 kg of soil and put it into a
plastic bag. Bring it back to school for
further investigation.
19.10 Study of local habitats
10. Examine the plants:
(a) Trees which touch or have their
perpendicular
crown
projections
overlying the transect line should all
be included in you investigation.
(b) For each tree included
in your investigation,
measure its height,
diameter of trunk (at
breast height), crown
length, crown width
and also record its
corresponding position
on the transect line.
19.10 Study of local habitats
crown width
crown
length tree
height
perpendicular
crown projection
(c) Epiphytes on a particular tree along the
transect line should also be recorded.
Brief description is enough.
(d) Record all shrubs which touch, overlie or
underlie the transect line. For each type
of shrub, only record their heights and
corresponding positions on the transect
line.
(e) Include all fungi, herbs, grasses,
mosses, ferns growing near the transect
line. Record only the approximate number
of species encountered and notice the
most abundant species.
19.10 Study of local habitats
Laboratory work
1. Soil analysis
(a) Place the soil sample on a sorting tray
and sort out the animals for
identification.
(b) Record the colour, smell and nature
(hard, soft, loose or sticky) of the soil.
(c) Add a little soil sample to a beaker.
Add some distilled water and test its
pH.
19.10 Study of local habitats
2. Place the litter in a tray and use forceps
or glass rod to sort out the animals.
Identify and count them.
3. Try to find out the adaptive features
shown by the living organisms collected
from the site.
19.10 Study of local habitats
E. Discussion
1. Construct a slope profile of the woodland.
2. Use the plant data to draw a profile
diagram. The diagram should be able
to show the position and relative sizes
of the plants including trees, shrubs,
herbs and grasses.
3. How can we explain the distribution
pattern of organisms in terms of the
physical limiting factors?
19.10 Study of local habitats
4. Propose food webs for the woodland.
5. How do the organisms adapt to living in
the woodland?
6. Are there any effects of human impact
on the woodland?
19.10 Study of local habitats
Field study 2
Studying a freshwater stream
The major factor influencing the distribution
and abundance of living organisms in a
freshwater stream is the directional flow of
water from upstream. In order to survive in
streams, organisms there may have different
morphology and physiology compared to
those in terrestrial habitats.
Teachers should ensure that any stream is
not polluted with faecal matters before
allowing students to work on it.
19.10 Study of local habitats
A. Aims
Refer to the aims of Field study 1, try to list
the aims of studying a stream.
B. Precautions
1. Wear canvas shoes with adequate soles.
2. Wear trousers instead of shorts. Wear
long-sleeved shirts.
3. Be careful of slippery rock surfaces.
19.10 Study of local habitats
19.10 Study of local habitats
C. Equipment
Metre-rule
Compass
Thermometer
1 Hand lenses
1 Light meter
1 Rubber gloves
2
1
1 pair
Flow meter
Trowel
Soft brushes
Sorting tray (white)
Beaker (100 cm3)
Reagent bottles
1
1
2
1
2
2
2
4
2
19.10 Study of local habitats
Fish nets
Forceps
Plastic bags
Transect line
Vials of different sizes 6
D. Procedure
Field work
1. With the help of your teacher, select a
section of a stream for study. Fix a
transect line across the stream. Record
the nature of the bottom and depth at
suitable intervals along the line. Be
sure to put any rocks you have moved
back to their original position. Use the
data to draw a cross sectional profile
diagram.
19.10 Study of local habitats
2. Draw a sketch map of the area in which
you are working. Indicate the flow
direction, composition of substrates
(sand/gravel/pebbles/boulders),
position of the trees which are related
to the habitat (Do the trees provide
shading to the stream bed?).
3. Record the appearance of the area of
your study, including water colour, smell
and any floating material or foam.
19.10 Study of local habitats
4. Measure the abiotic factors:
• Light intensity (on the water surface
and at the bottom of the stream)
• Temperature (both air and water)
• Average current speed
(For each factor, measure at different
points and consider taking an average)
5. Fill bottles with stream water and bring
them back to school for chemical analysis.
19.10 Study of local habitats
6. Use a trowel to collect about 1 kg of
sediment from different parts of the
bottom of the stream. Put the samples
in plastic bags and bring them back to
school for further investigation.
7. Record approximate numbers of plants
(including algae if possible). Note down
their roles in the ecosystem. Collect
some specimens for further microscopic
investigation.
19.10 Study of local habitats
8. Find, identify and record animals found
on the water surface, in the water, on the
surface of rocks at the bottom and
beneath the sediment at the bottom and
on the water plants. Put them in a white
sorting tray for identification and
observation. Record their external
features, classification and ways of
adaptation. All animals should be placed
back into the water before leaving the site.
19.10 Study of local habitats
Laboratory work
1. Analyse the water sample in the
laboratory. Measure the pH, dissolved
oxygen, ammonium content, phosphate
content, total suspended solids and
chemical oxygen demand.
2. Analyse the
sediment.
particle
sizes
Use the information to write a report.
19.10 Study of local habitats
of
the
Perform an investigation
of your own
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19.10 Study of local habitats
B150223-27
Day 1: Long valley
• http://matthewkwanbirding.blogspot.hk/p/lo
ng-valley.html
19.10 Study of local habitats
Day 2: your own investigation
19.10 Study of local habitats
http://ifieldstudy.net/notes/index.
html
B150223-27
19.10 Study of local habitats
Day 3:牛糞小生境大揭秘 Big
secret of the cow dung microhabitat
19.10 Study of local habitats
Day 4: Micro exploration
19.10 Study of local habitats
Day 5
Presentation!
19.10 Study of local habitats