Year 7 & 8Biodiversity

The BBC found that the majority of people believe biodiversity is a type of laundry detergent…

Our Biosphere…• The biosphere describes our living world,

from the upper areas of the atmosphere to the depths of the ocean.

• Biodiversity is a term to describe all the living organisms that make up the web of life on Earth. From a microscopic bacteria to a naked mole rat!

Activity: What would life be like without plants & animals?

We need high levels of biodiversity for clean air, food, fresh water, clothes, energy, and for medicine.

Without biodiversity life for humans would be both dull and dangerous!

The biosphere is far too big for scientists to study,

so we study smaller things called ecosystems!

Ecosystems

• Any group of living (biotic) and non-living (abiotic) things that are connected together in a self-sustaining way are called ecosystems.

• An ecosystem can be as large as a desert or a lake or as small as a tree or a puddle!

Guess what? Everything in the natural world is

connected.

Abiotic and Biotic factors in an ecosystem…

What are the major parts of an ecosystem?

All living parts of an ecosystem are known as BIOTIC. For example a bush or lizard

All non-living components of an ecosystem are ABIOTIC. For example a rock or humidity.

Sort the following ecosystem parts into abiotic and biotic components.

Soil, kangaroo, atmosphere, cactus, sunlight, water and bacteria.

Habitats

Ecosystems are made up of habitats and micro-habitats. A habitat is the place where an organism lives.

A habitat will provide the organism with the resources it needs for survival.

Populations and Communities

A population is a group of organisms of the same kind that live in the same area. Like a population of bees.

A community can be described as different species interacting in the same area. Like bees, ants and daisies.

We can show how organisms connect through food chains

and food webs…..

Food webs/chains…• The arrow shows the flow of

nutrients. The arrow points to where the energy goes too.

Trophic level

Humans have been damaging our biosphere and ecosystems, which is effecting our biodiversity!

What has happened in these pictures below?

Threats to Biodiversity

Since European settlement, we have achieved the worst record of mammal extinction in the world! We are fragmenting the connections in our ecosystems.In Australia we are famous for our marsupials, but now almost half of them are either extinct or threatened with extinction!

The Sixth Mass Extinction

• Many scientists believe that that we are in a period of mass extinction caused by humans.

• Globally, humans have caused the extinction of a total of 86 flora and 723 fauna.

The International Union for Conservation of Nature (ICUN) Red List is a global list of threatened species.

It divides up animals into categories such as:•Vulnerable •Endangered•Critically Endangered•Extinct in the wild•Extinct

Although humans have been changing the Australian landscape for 50,000 years or more, the changes in the last 200 years have caused terrible loss of soil, vegetation and biodiversity.

This sounds bad! What on earth are we humans doing to cause all this?

• Pollution: Pollution of our oceans, our air, our rivers and our land. Pollution from cars, industries, energy production, and manufacturing.

• Over-fishing in our oceans has drastically reduced fish stocks, to the point of extinction in some cases.

Human Changes

• Feral plants and animals continue to cause devastation to native plant and animal communities, including those in our oceans.

• Over-consumption: We’re simply buying and eating and consuming too much stuff!

• Climate change will potentially cause further problems and threats to biodiversity.

• Habitat loss: We’ve been clearing or damaging the natural environment to make way for all the stuff that we need (like building houses, grazing sheep and cows, and growing food) that there aren’t many healthy habitats left for our native plants and animals.

THEN NOW

• This can start to sound a lot like very bad news. But don’t worry; it’s not all bad. There are things that you can do to help stop the damage to biodiversity.

• And there are lots of people who are already working hard to help protect and restore our biodiversity. But they do need your help. In fact, they need the help of everybody!

• So what can you do?

Tips for helping biodiversity

• Use less stuff!• Plant native plants in your garden - good for the birds, butterflies

and bees, and good for the soil!• Pollute less by driving less, buying less and wasting less and

thinking about what you’re flushing down the drain!• Buy organic fruit and veggies if you can - these haven’t been

sprayed with chemicals that can harm biodiversity!• Lock up your pets at night - the night belongs to native animals!• Donate some time to vegetating or cleaning up a local wildlife

park!• Choose sustainably harvested fish to have with your chips!• Spread the word!• For more tips and more information on biodiversity visit the Our

Cool Australia site.