BiodiversityYear 9 & 10

Biodiversity is not simplythe variety of plants and animals

on Earth…

Biodiversity is…..

The total of all living organisms found on Earth:plants, animals, microorganisms

andthe genes they contain

andthe ecosystems they are a part of.

There are three levels of biodiversity

1. Genetic diversity

2. Species diversity

3. Ecosystem diversity

1. Genetic diversity

Genes are the basic units of heredity!High genetic diverse means there is a great variety of genes that are present in the population. This maximizes the adaptive potential for a species and reduces it vulnerably to change.

Although a species may look the same, genetic diversity in a population is essential for survival.

High genetic diversity maximises survival potential of a species by:

-increasing the number of different alleles in the gene pool-increasing the chance of adaptation to change/threat

1. Genetic diversity continued…

2. Species diversityA species is a group of organisms capable of interbreeding and producing fertile offspring.

For example: A donkey and a horse are from different species because their offspring is infertile.

2. Species Diversity continued…

Two types:

• Species richness: the number of different species in a particular area

• Species abundance: the amount (abundance) of individual species in a particular area

Compare Species Richness and Species Diversity in these two samples

Sample 1 Sample 2

3. Ecosystem Diversity

Different species depend on a variety of ecosystems.

Common ecosystems include: Forests, Rainforest, Woodlands, Shrublands, Marine, Freshwater, Estuarine, Heath, Grassland, Tundra, Alpine, Desert, Riparian, Wetlands

Let’s reflect…What is an ecosystem?A community of organisms that depend upon and interact with each other and the abiotic factors surrounding them.What is a community?A number of populations of different species interacting within a particular region.What is a population?Groups of organisms belonging to the one species and living together in an area

EcosystemsAny 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 lake, or as small as a tree or puddle!

What are the major parts of an ecosystem?

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

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

Sort the following ecosystem parts into abiotic and biotic components:

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

Did you know…

Earth has existed for 4.5 billion years.Life has existed on Earth for 3.5 billion years.Life today is therefore a result of evolution that has taken place over those 3.5 billion years.Modern humans have only existed for only 100,000 years but we are having negative effects on biodiversity!

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

What has happened in these pictures below?

Threats to Biodiversity

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.

Why conserve biodiversity?

1. Ecosystem Services

2. Biological Resources

3. Social Benefits

1. Ecosystem services• Clean drinking water• Soil formation and protection• Nutrient storage and cycling• Pollution breakdown and

absorption• Contribution to climate stability• Maintenance of ecosystems• Pollination of crops

2. Biological Resources

• Food• Medicines• Resources use• Ornamental plants• Breeding stocks and population

reservoirs

3. Social Benefits

• Education• Recreation and research• Cultural• Aesthetic

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

Without biodiversity, life for humans would be both dull and dangerous. So we must conserve it.

Conservation

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

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

Conservation Categories

Although humans have been changing the Australian landscape for 50,000 years or more, the changes in the last 200 years have caused a 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

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?

It’s not all bad

Tips for helping biodiversity

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

Cool Australia site (www.cool.australia.org).

Biodiversity Review Questions:

Q1. What are the three levels of biodiversity?Q2. Why is genetic diversity important?Q3. What are the two components of species diversity?Q4. List 3 reasons why we should conserve biodiversity.Q5. What are conservation categories?Q6. How can we help conserve biodiversity?