Ecological or environmental
are inhabited by a particular
species (Abercrombie M.,
Hickman C, Johnstone M.L.
1966, A dictionary of Biology.
London Penguin Books.)
Why Conserve??
Maintaince of habitat,
keeps species diversity high.
Terrestrial biodiversity is up to 25
times greater than ocean biodiversity
(Benton M. J. (2001). "Biodiversity on
land and in the sea". Geological
Journal 36 (3–4): 211–230)
The more species there are, the more
secrets they may hold. Plants and
animals of different species may have
different, unique and ultimately
beneficial biochemicals that may prove
to be important in curing diseases.
High diversity is
insurance against
extinction of a lineage. If
one or a few species
became extinct, there
may be other closely
related species that can
perpetuate the lineage
More species means bacteria,
virus, and parasites have a
more difficult time decimating
an ecosystem. Agricultural
fields, which may have rows
upon rows of crops of the
same species, for example,
are more susceptible to
diseases and insect attacks
than are highly diversified
natural plant communities.
Ecosystem function/services
What we can get from plants
Trees: filter rainwater
absorbing chemicals
as result safe for
humans to drink
Bacteria absorb pollution
from river making the
water useable again but
decrease the oxygen
concentration
Protection of genetic resorces
Potential value
to achull value
what value is
perceived to
be and what
the value
achually is.
Changing can cause
some plants to die out
as they are out
commpteted
Rapid enviro changes
Global warming, weather
patterns changing
Tourism
Finances
Aesthetically Pleasing
How??
Decisions between species diversity and density.
Dceide what
you want to
conserve.
(dependent
on public
opinion)
Climax
community
with fue
species or
high diversity
but fluxuating
Scientific Principles
Plant Strategy Theory
Competitors
Low Stress Low
distaurbace
Create a:
high dense canopy
Block light to plants underneath.
Restrict resource: Light
Rapid acending mono-cluture layer
Only one type of pant dominates
Defined layer of leaf production
To dominate the
canopy layer and
reduce light to
others maximising
for self
High mean growth rate
Has rocket groth: 'Jumps' in hight
Quickly grows
Eg Braken
Divided into three categories
Competitors, rudral and stress
tolerant
In a triangle of
three types but
also contimum
between them all
Stress Tolerents
High stress Low disturbance
Long life with limited flowering
only flower with
optimum conditions;
nutrients, water, light
due to huge resorce
expenditure must know
they are going to survive
and produce viable
seeds
Low growth rate
Only grow
with optimum
conditions
Low palitiblity
resource use why?
resources are
scares and
have put
resources into
leaves then
don't want the
biomass eaten!
then don't
need to
expend
resources on
repair
taste horrible
Ruderals
high disturbance,
low stress
Short life
and early
flowering
As early dominators of disturbed ground must establish quickly before others
dominate and disperse seeds to hopefully continue linage. seeds can
germinate after next disturbance due to dormancy.
Pass along genetic info.
Short phase of production
Seeds live on
after original
plant death
continuing the
lineage
high mean potential
relative growth rate
Grow quickly
Large proportion
of annual
production
devoted to seeds
main aim is to dispersal of seeds
eg Shepards Purse
Digrams
Regeneration
vegetative expansion
Low disturbance intensity
Grow slower than seed germination
Seasonal regenation
grow at beginning of season
Bluebells before the trees have leaves
persistant seed banks
pre-programed to flower
Persistant juveniles
don't flower until optimum time
High dispersal, hope
seeds hit optimum place
Co-Existance
The Dormant
major
contributor to
total biomass of
plant community
influences identity ,
quantity and disruption
of associated spevies
Oak Tree
Mechinisims
influences neighbours
= or -
Achieves
greater
biomass
than that of
associates
+/_
controlled
feedback
Mutiple species
can exist in same
place due to
seonality Bluebells
flower before trees
have leaves to
make optimal
sunshine
Factors that limit the
expression of dominance
by any one species allow
co-extsence
Naurall processes and
stresses and habitat
management can limit
the expression of
dominance
Succession
How communities develop and change over time
Primary or Secondary or arrested
P= removal of
all spoil and
plant starting
with parent
rock
caused by lava, Mud slides
S= starting with soil but no plants
Winter storms, Fire
A=when we stop the succession taking place
Heather moorland (Burning)
Chernoble town (pripyat)
seen as stopped
Arresting succession and
its now a forest with
whole lot inc animals.
Benifits us
more to keep as
is.
Caused by
disturbance
and can be
a cycle
more than a
process.
Disturbance
Type
Scale Volcano to
herbivory (fire to
eatten)
density
independent or
dependent
severity
magniude of
change in
resorces of area
Intensity
energy realised
over the per unit
area over time
mount st helens in 1980 24
megatons thermal energy (7
by blast, rest through release
of heat) and 4 billion board
feet of timber lost.
measeure quantative ly
freq. and timeing
Oten not often, how
much destruction
depends on time of year-
fseed dispersal/mateing
Mount St helns erupted 21
times across 6 years
causing diruption,
happened often over a
small time fram eand has
now settled down.
Pattern and size
Often -winter storms
level of
devistation
Island Biogeography theory
relationship between
species richness and
habitat area is one of
the most consistant
ecollogical patterns
more than area?
yes depends on the
area and the
isolation of the island
Islands are land
which is
surounded by
hostile land
Predictions
Large Islands suport
more species
compared to small
island
Specise number
should decline with
increased isolation
no of species
should become
constant over
time
Continual turn over
with immagration an
extinction
Complications
Dosnet take
evolution into
account
Specise not equal
(as theory states)
due to food chain
Habitat
range not
just size
comunity
develop over
time -Assembly
Rules
Sampling
Phase 1
National Vegatation Classification
Uk Wide
Indication of
what should be
in the location.
And where the location should be.
Can give
indication with
location if area
is natural or has
been planted
habitat survey
Indicators
Indicators can indicate pH
level, land management,
wetness of soil
Species- Bog Cotton- indicates perment wet soil.
May flies indicate
good water quality
and low polution
Phisically go out and survey
Gives definite of
boundaries
Can see exactly what
plants grow there and
the exact conditions
bog and how wet!
Target notes
things are not
going to see
on the map
Arial photos and salilight immagery
infa red indicated heat
which can be produced by
crop(monoclutuer) lnd and
can show the defintes of
the feilds.
Target notes
Written in the feild
Gives details
of area, birch
wood, high
canopy mature
trees