1. 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.

2. 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.

3. 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).

5. The earth’s biomes 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 Desert Tundra - cool, treeless, and dry Tundra Chaparral or scrub - coastal area with hot, dry summers and mild, cool, rainy winters Chaparral or scrub Taiga or Coniferous Forest - cool and dry, with coniferous trees Taiga or Coniferous Forest Temperate Deciduous Forest - cool and rainy, with deciduous trees Temperate Deciduous Forest Grassland - Windy, partly dry sea of grass with few trees, including tropical savanna, prairie, steppe, pampas, etc. Grasslandsavannaprairie 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 Tropical Rain Forest Land Caves - cool and dark Land Caves Wetlands - there are many types of wetlands, including swamps, marshes, moors, bogs, fens, sloughs, etc.swamps Freshwater Marsh - a wetland located near creeks, streams, rivers and lakes Freshwater Marsh Temperate ponds

6. 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).

7. 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.

8. 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

9. 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.

10. The most productive areas in the world given their natural production of living matter are………. swampsswamps and marshes: 2500 g/m²/yr of biomassmarshes tropical rain foreststropical rain forests: 2000 g/m²/yr of biomass algal bedsalgal beds and reefs: 2000 g/m²/yr of biomassreefs river estuariesriver estuaries: 1800 g/m²/yr of biomass temperate foreststemperate forests: 1200 g/m²/yr of biomass cultivated landscultivated lands: 600 g/m²/yr of biomass desertsdeserts and tundras: less than 200 g/m²/yr of biomasstundras This is based on Net primary production which is the rate at which biomass is generated in a given area, mainly due to photosynthesis.primary productionbiomass