Table Talk What do you think the word Biodiversity means?

Biodiversity & Sustainability

A. What is Biodiversity? The variety of life in an ecosystem Variety of Genes Variety of Species Variety of Ecosystems

Variety of Genes

Variety of species This is the total number and kinds of different species on earth.

Variety of Ecosystems Smaller ecosystems such as a garden, or even microhabitats

TREES IN a Forest

This food web has low biodiversity Rabbits eat grass. Foxes eat rabbits Foxes Rabbit Grass

This food web has low biodiversity A disturbance hits… A drought happens and kills all the grass. Foxes Rabbit Grass

This food web has low biodiversity What happens to the foxes? Foxes How many species do we have left? 0! Rabbit BIG change? Grass

This food web has high biodiversity Let’s add a few more species to our original ecosystem Foxes Lettuce Rabbit Chickens Grass

This food web has high biodiversity A disturbance hits… A drought happens and kills all the grass. Foxes Lettuce Rabbit Chickens Grass

This food web has high biodiversity The food web started with high biodiversity High biodiversity = stable ecosystem One change… didn’t really do anything! What happens to the foxes? Population size decreases… a little Foxes Lettuce Rabbit BIG change? Chickens Grass

High Biodiversity Biodiversity IS… *Many Different Kinds of organisms…. *many Different organisms filling the same energy role (niche)in the same ecosystem High Biodiversity

Low Biodiversity Biodiversity is NOT *Larger populations of the SAME organism….. Low Biodiversity

More organisms at each energy level is better

High or Low Biodiversity?

Let’s see how biodiversity effects the stability of an ecosystem!

Evidence of a stable ecosystem… Many Different organisms in the same energy role (niche) If disaster strikes one species, there is food to choose from. Equilibrium- proper balance...NOT changing=SUSTAINABILITY

Stability More species at each role = healthier ecosystem More diverse energy level = more sustainable ecosystem

Which ecosystem is more stable why?

Answer: Food web A Variety of organisms filling the same energy role If something happens and species dies out others fill the same role Ecosystem A is better able to handle environmental stressors

which describes biodiversity supporting sustainability. (table talk) Student A: A disease causes the coyote population to decrease, which causes the rabbit population to increase Student B: A freeze kills one of the many plants bees pollinates from. The bees survive by getting nectar from the many other plants they get nectar from. Student C: there is an increase in wheat plants causing the population of mice to increase.

More links = More Stability Healthy Ecosystems More links = More Stability

Large leaves to get light So what is a niche? The way an organism uses the environment. Decomposer Climb to the light Large leaves to get light Herbivore Nesting High Predator Or in a hole.. Autotroph Diurnal Nocturnal When do I get to eat? Where will I get food? What do I get to eat? Where do I get to live?

Why is an organisms niche important? balance!!! 1. to keep the balance 2. they provide resources for other organisms Who is missing? So we don’t lose balance

How does biodiversity support ecosystem stability Genetic variety = greater chances species survival over time (natural selection) Variety of species= more organisms can fill the same niche Variety of ecosystems= everything doesn’t live in the same place. (more resources) If Disaster Strikes it’s “business as usual”

B. Why is it important? Medicines Recreation and Tourism Indicates health of biosphere

Quick Facts There are millions of species on Earth Loss of about 50 per day Normal should be 1 per 5 years Tropical Rainforests hold a large percentage of Earth’s diversity 30 Extinction Hotspots Biodiversity maintains the health of the earth (fill in the next blank) and its people. It provides us with food and medicine and contributes to our economy. For example, we use plants and animals for food and medicine and we can harvest plants and animals and sell them to make money. In Manitoba, the fishing industry contributes $150 million annually to our economy. Biodiversity tells us a lot about the health of the biosphere. The greater the variety of species, the healthier the biosphere is. Why is this? (pause, have students brainstorm answers). [Possible answers] more species = more links in food chains/webs = more stable more plants = more food for other animals (more oxygen too) more genes = better chances for survival through adaptation a variety of ecosystems = more habitat for different species

Biodiversity is diminished by… Habitat Loss Overhunting Climate changes Disease Natural Disasters Invasive Species

Hold up… Don’t these things happen all the time? How do ecosystems stay healthy if there is always stress?

Healthy Ecosystem More Biodiversity = Healthier ecosystem= sustainable The more sustainable the ecosystem is the better it is at dealing with stress!

Biodiversity and Sustainability Oh yes…they have a relationship! biodiversity = sustainability

E. Invasive Species Let’s take a closer look… What is an invasive species? An exotic species (not native to the area) that negatively impacts the ecosystem

How do they upset the balance? Here is an example: Rabbits in Australia Timeline: 1788 Rabbits brought to Australia for food 1827 Rabbits begin to overrun the countryside 1859 So many, that killing 2million/year had no effect on the population size!!!! Why did this happen?

Back to the Niche… So what did they do???? There were no native species in the ecosystem with the ability (role) to control the rabbit population! No natural predators = Too many rabbits! So what did they do????

Oh they tried… They tried to hunt and trap them… Fail They built a fence to contain them… They introduced a virus to kill them… Semi-success, but now many are resistant to it This didn’t happen until 1950!!!

So what has happened to the ecosystem? Rabbits have devastated the Australian lands! Billions of dollars! Many native species now under severe stress LOSS OF BIODIVERSITY…. Loss of Sustainability! European Rabbits in Austrailia

Remember… More Biodiversity = More Sustainability This means a healthy Earth and a healthy you!

How can we improve sustainability and biodiversity? Some possibilities: Reduce, Reuse, Recycle Care for the environment Limit monoculture Farming Responsible pet/plant owners Others???