Transcript Definition of Urban niche

Definition of Urban niche
Within an ecosystem all living
organisms occupy a niche. Their
niche is the place where they live
(their habitat) and how they
interact with other species (their
role in the ecosystem).
The woodlouse's habitat is under logs and stones and,
particularly at night when it's cool and damp, under leaf litter
The woodlouse's role in the ecosystem is (a) feeding on dead
plant material, breaking it down into small pieces helping to
speed up decomposition by fungi and bacteria and (b)
providing a food source for a range of other species, e.g.
toads, shrews, hedgehogs and other invertebrates
Starter - how many different
niches are there available for plants
to colonise
Horizontal bare
tarmac
vertical stone wall
vertical brick wall
tops of walls
rubble strewn
ground
• Key point – different types of
rubble/brickwork etc create their own
microhabitats
Human use means urban ecosystems are
subject to more change and at a faster
pace than any other ecosystems.
Changes in:
Drainage
Micro-climates
Composition of surface material
Introduction of new species (accidentally +
deliberately)
Removal of established species
= ecosystem unlikely to reach stability
(Nelson pg 98)
Types of plants which initially colonise a site
are influenced by:
Slope – horizontal/gentle slopes debris
accumulates to create soil
Moisture availability – horizontal/slopes rainwater
accumulates, steep slopes faster runoff
Aspect – south facing slopes = warmer + drier
Porosity (ability to hold water) – surfaces that
hold water are colonised more quickly
Surface roughness – allowing plants to get a hold,
glass + metal are too smooth for most plants
Pollution levels – depend on previous use of the
site. Substances that are toxic to plants e.g. lead
may contaminate the land
Keywords (match the correct definitions
to each key term)
Conservation
Ecology
Sustainable
Development
Substrate
The surface on which a soil
forms. This is usually rock, but
can also be a deposit such as river
sediments, glacial till or boulder
sediment.
Preservation of the natural
environment
The study of the relationship
between living things and their
environment
The management of resources in
such a way that the ability of the
system to replace itself is greater
than the level of exploitation
Structure of an urban ecosystem
Sort the below features into the correct categories
Inputs
Air
Ecostructure
(The City)
Residences
Outputs
Food
Manufactured products
Sunlight
solid waste
Emigrants
Changes air and gases
Power
Fuels
Vehicles
Offices/Factories
Water
Emigrants
Raw materials
Money
Governments/organisations
Sewage
How did you do?
Key point: Human agents (e.g households, businesses, developers,
governments) and biophysical agents e.g. local geomorphology, climate.
These choices give different patterns of development, land use and
infrastructure density. In turn this affects ecosystem processes both
directly and indirectly (in and near the city) and remotely thorough use of
resources, generation of waste/pollution.
The Colonisation of Wastelands
E.g.
The colonisation of most wastelands is a lithosphere type succession
Many wastelands are often temporary becoming redeveloped after a
couple of years but if they are allowed to develop the following is likely
to occur:
Let’s look at some local examples....
Waste ground, Upper Park Road, Rusholme
Wasteland off Clayton Lane
The engineering works is long gone. In the distance are the modern
additions of Eastlands Stadium and the "artwork" called "B of the Bang",
which has now been removed.
The view from the corner of Hollinwood Avenue and Long Lane, well
before the M60's coming. The Rochdale Canal is on the left with former
cotton mills on Whitegate Lane, Chadderton, visible in the distance.
Cheadle Lower Mill
Originally a water-powered cornmill,
the site was successively developed
to become a Bleach Works, a laundry,
a detergent factory and finally a ruin.
The place was in use until 1993 so
this picture gives an indication of how
quickly dereliction can set in. The
chimney is the only untouched
element!
Sept 2007
The site has now been
cleared for housing (June
2008) –
What has happened to the
succession?
What might happen if the
site is now left derelict?
Although some evidence
of industry remains....