Transcript Ecosystem - bankstowntafehsc

This is the start of your Year 12 HSC
Course if you only want to do Year 11 you
will need to see me about a research
project based on fieldwork – please
come to class next Tuesday to
discuss
This work is integrated with the
work on BIOSPHERE from our Yr 11
section.
Year 12 Topic – syllabus overview
Ecosystems at Risk
• Students learn about:
• ecosystems and their management
• case studies of ecosystems
Plus TWO case studies of different ecosystems at risk
to illustrate their unique characteristics – our case
studies will be inter-tidal wetlands and coral reefs
focussing on Salt Pan Creek and the Great Barrier
Reef.
You must study both the case studies and overview
work on ecosystems.
Ecosystems at Risk:
• The Biosphere is that part of the earth’s surface
where all life occurs. It extends from sea level to
over 9,000 metres high and to a depth of nearly
10,000 metres.
• This is the zone that supports all life on earth.
• Biomes are large complex regions of the
biosphere such as forests or grasslands that have
similar climate or vegetation features eg. Tropical
rainforests, deserts, savanna grasslands,
coniferous forests, alpine. (see next slide for the
variety of biomes on earth).
The earth’s biomes
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The Earth has many different environments, varying in temperature, moisture, light, and many other
factors. Each of these habitats has distinct life forms living in it, forming complex communities of
interdependent organisms. A complex community of plants and animals in a region and a climate is
called a biome.
Some of the biomes on Earth include:
Desert - very dry, either hot or cold
Tundra - cool, treeless, and dry
Chaparral or scrub - coastal area with hot, dry summers and mild, cool, rainy winters
Taiga or Coniferous Forest - cool and dry, with coniferous trees
Temperate Deciduous Forest - cool and rainy, with deciduous trees
Grassland - Windy, partly dry sea of grass with few trees, including tropical savanna, prairie, steppe,
pampas, etc.
Mountain biomes: there are a lot of different mountainous biomes, from grasslands at low altitudes, taiga
(coniferous forests) below the treeline, and alpine (the same as tundra)
Temperate Rain Forest - cool and wet
Tropical Rain Forest - warm and very wet
Land Caves - cool and dark
Wetlands - there are many types of wetlands, including swamps, marshes, moors, bogs, fens, sloughs, etc.
Freshwater Marsh - a wetland located near creeks, streams, rivers and lakes
Temperate ponds
What are ecosystems?
• Ecosystem - an area that contains organisms
(e.g., plants, animals, bacteria) interacting with
one another and their non-living environment.
Ecosystems can be of any size (e.g., forest, pond).
• Ecosystems may be classified according to their
CLIMATE (eg. Alpine or desert), VEGETATION (eg.
Tropical rainforest or savanna grassland),
PHYSICAL FEATURES (eg. Coral reefs),
TERRESTRIAL (eg. Land based such as grasslands
or deserts) or AQUATIC (eg. Freshwater or
saltwater such as coral reefs or wetlands).
Variations in complexity and scale
• Ecosystems vary in complexity and scale from
the Great Barrier Reef in north Queensland
which extends for over 2,000 km, has over
2,000 fish species and 500 coral species to
that of a pond or sand dune system on a
beach.
BIOPHYSICAL INTERACTIONS
• The interactions of the biosphere, lithosphere,
hydrosphere and atmosphere together
• The interaction of food chains – feeding
relationships and population changes
• The interaction of biogeochemical cycles such as
Carbon-Oxygen cycle, Nitrogen cycles,
• The interaction of fires, storms, floods
INTERACTIONS MEANS :
SOMETHING HAPPENS -> LEADS TO AN
ACTION/EFFECT/IMPACT
More terms
BIODIVERSITY – the variety of species or life forms and includes:
• GENETIC DIVERSITY – variations in the genetics of individuals within a species
• SPECIES DIVERSITY – the variety of species within different habitats
• ECOLOGICAL DIVERSITY – the variety of biological communities that interact within
their non-living environment
OTHER TERMS TO KNOW:
• FOOD CHAIN – set of organisms, each eating or feeding on the preceding one eg.
Grass -> grasshopper -> bird
• FOOD WEB – the network of interconnected food chains
• HERBIVORE – organisms that consume plants as their only food source
• CARNIVORE – organisms that consume meat as their only source of food
• OMNIVORE – organisms that consume both plants and meat as food
• BIOMASS – The total mass of living matter within a given unit of environmental
area.
• SUCCESSION is the change in the structure and species combination of a plant
community thus leading to a more complex community over time.
The most productive areas in the
world given their natural production of
living matter are……….
swamps and marshes: 2500 g/m²/yr of biomass
tropical rain forests: 2000 g/m²/yr of biomass
algal beds and reefs: 2000 g/m²/yr of biomass
river estuaries: 1800 g/m²/yr of biomass
temperate forests: 1200 g/m²/yr of biomass
cultivated lands: 600 g/m²/yr of biomass
deserts and tundras: less than 200 g/m²/yr of biomass
This is based on Net primary production which is the rate at which biomass is
generated in a given area, mainly due to photosynthesis.