Learning Objectives:
- Biodiversity includes the diversity of genes, species and ecosystems; measures of biodiversity rely on classification and are used to make comparisons across spatial and temporal scales
What is Biodiversity?
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Some Necessary Definitions...
Biosphere:
- All environments on Earth that organisms inhabit. The combined sum of all ecosystems.
- All of the organisms of a particular area along with the non-living components of their environment and the interactions between these components. It is a self-sustaining system.
- Remember: Ecosystems can vary greatly.
- This is the physical and chemical description of where an organism lives
- Within an ecosystem there can be many HABITATS
- It may describe the ecosystem eg. Polar Bears' habitat is Arctic Canada
- It may describe the dominant vegetation. eg Heather moorland is the habitat for the grouse
- It may describe the substrate a species lives in. eg. Pike (Esox lucius) are found in freshwater ponds and lakes.
Species:
A group of morphologically similar creatures which:
A group of morphologically similar creatures which:
- can interbreed to produce fertile offspring
- are ‘reproductively isolated’.
Which has more biodiversity?
Why is biodiversity important?
Biodiversity provides us with:
- Natural Resources (food, water, wood, energy, and medicines)
- Natural Ecosystem Services (air and water purification, soil fertility, waste disposal, pest control)
- Aesthetic pleasure (which improve both tourism and local mental health. Flow-on economic benefits)
So...how biodiverse is our planet?
- 1.7—2.0 million species have been identified named and recorded.
- Estimated that 100 million exist.
The biodiversity is everywhere!
- Every continent and habitat has unique life forms
- Concentrated in the tropics
- We also have some mega-diverse locations.
Biodiversity Hotspots
- Myers et al. (2000) published an incredible paper wherein they identified the world's ecosystems which were MOST in need of protection.
- They selected areas of the world with:
- extremely high diversity (at least 1500 plant species)
- extremely high disturbance (at least 70% habitat loss)
- If conservation efforts are focussed to these hotspots we will be protecting MANY species at once and priorising the most damaged ecosystems.
- More than 20 years later their system is still used worldwide to refer to regions of high diversity and high need.
Our Biodiversity is declining...Why?
"The decline of Earth’s biodiversity is an unintended consequence of multiple factors that have been enhanced by human activity. They can be summarized by the acronym HIPPO, with the order of the letters corresponding to their rank in destructiveness.”
E. O. Wilson “The Creation”
Habitat loss
The greatest reason for biodiversity loss.
Habitat loss is due to:
Invasive, exotic species
Introduced from elsewhere outcompete native species because they:
Pollution
Population (Over-population)
Overharvesting/Overuse
E. O. Wilson “The Creation”
- H Habitat loss, including that caused by human-induced climate change.
- I Invasive species (harmful aliens, including predators, diseases, and competitors that displace native species
- P Pollution
- P Population, Human overpopulation to be exact, a root cause of the other four factors
- O Overharvesting, Overuse (hunting, fishing, gathering)
Habitat loss
The greatest reason for biodiversity loss.
Habitat loss is due to:
- Conversion of natural areas to farms, houses, etc
- Fragmentation of ecosystems by human activities, housing, transportation, agriculture, etc.
- Simplification of genetic diversity and complex ecosystems by planting/selecting monocultures.
Invasive, exotic species
Introduced from elsewhere outcompete native species because they:
- Have no natural predators
- Colonize disturbed habitats quickly
- Have a high biotic potential (r-species)
Pollution
- Oil spills, human agricultural waste, fertilization, pesticides, acid deposition, greenhouse gases etc
- Caused by human activities has a negative effect on biodiversity
Population (Over-population)
- 7.2 Billion and counting.
- The expansion of human population and affluence, especially in the developing world harms natural ecosystems.
Overharvesting/Overuse
- Overhunting, overfishing,
- destructive harvesting practices (cyanide, dynamite),
- illegal trade,
- exotic pet industry
Why do some species thrive and others decline?
The endangered species typically exhibit some of the following characteristics...
- Low reproductive rate (biotic potential)
- Feed at high trophic levels (apex predator)
- Large body size
- Specialist
- Specialized feeding habits
- Specialized nesting and/or breeding areas
- Specialized feeding habits
- Fixed migratory patterns
- Found in one place or region
- Rare
- Commercially valuable
- Negative human interactions including attacks on people or livestock
![Picture](/uploads/1/2/5/9/125983434/extent-of-deforestation-in-borneo-1950-2005-and-projection-towards-2020_orig.jpg)
THE EXTENT OF DEFORESTATION IN BORNEO 1950 to 2020
https://www.google.com/url?sa=i&url=https%3A%2F%2Fintotheheartofborneo.wordpress.com%2F2009%2F04%2F19%2Fdeforestation-in-borneo-1950-2005%2F&psig=AOvVaw1okY7WJIyL1oAKEoZnbVYo&ust=1611204235527000&source=images&cd=vfe&ved=0CAIQjRxqFwoTCKDy09TZqe4CFQAAAAAdAAAAABAJ
Atlas of Living Australia
Australia's Biodiversity is summarised at this amazing site: www.ala.org.au/
ACTIVITY: Create a booklet titled - 'The biodiversity of Geraldton.'
The booklet must include:
ACTIVITY: Create a booklet titled - 'The biodiversity of Geraldton.'
The booklet must include:
- A short summary of Geraldton is in terms of longitude and latitude, closeness to the coast, altitude, climate, and human population.
- A short summary of Geraldton's quantitative biodiversity (just numbers) including total number of species, mammals, birds, reptiles, amphibians, insects, fish, molluscs, angiosperms (flowering plants), gymnosperms (non flowering plants), fungi, algae.
- For each taxonomic group, choose one species and create a profile for it. The profile should include: 3 pictures, a map of its distribution in Australia, its conservation status, and an interesting fact about it (hint; choose species that have lots of info recorded).