What is Biodiversity? The number and variety of species in an ecosystem More inclusive of all diversity: the totality of genes, species, and ecosystems of a region How many species are there on Earth? Estimates range from 5 to 100 million ,000 minimum Phylogenetic Tree Click Click The relatedness of identified species can be found here: Click Click How do we know? It can be hard to estimate total diversity within an ecosystem 4 main sampling techniques are used SEE TABLE 3.1 ON PAGE 90 Canopy fogging Quadrant sampling Transect Sampling Netting Why is Biodiversity Important? Still a topic of much scientific research Main Idea more biodiversity = more resistance to change What happens if insecticides are used? What happens if Grouse are hunted? Why is Biodiversity Important? More biodiversity = more resistance to change Maintenance of ecosystem services Potential for new discoveries (eg. medicines) Economic benefits (exploitation / ecotourism) Natural beauty / fascination / personal connection What are Ecosystem Services? Through the natural processes that take place in nature, ecosystems perform a number of seemingly free services which sustain humanity and all other life on earth eg 1 - Transfer of energy The suns energy is captured and moved through food webs which provides food for all creatures on the planet eg 2 - Water purification Many ecosystems ultimately provide clean purified water as a result of the biotic and abiotic features within them. Marsh ecosystems are particularly important natural water filters. eg 3 - Oxygen cycle The huge variety of autotrophs on Earth remove carbon dioxide from the atmosphere and replenish oxygen supplies More Ecosystem Services When there is more biodiversity, there is: more nutrient cycling (eg. Carbon / Nitrogen) more photosynthesis = more total productivity + reduced climate change less spread of disease More forested land: Holds soil in place Reduces runoff Increases rainfall / reduces evaporation What is Currently Happening To Biodiversity? Looking Backwards 6 th Mass Extinction? Biodiversity Hotspots Originally 25 regions Today, 34 identified regions of particularly large, unique plant diversity, under strong threat of habitat loss must contain at least 0.5% or 1,500 species of vascular plants as endemics has to have lost at least 70% of its primary vegetation. Biodiversity Hotspots When established in 1999, covered about 11.8% of earths land surface and contained were believed to contain 44% of earths plant species and 35% of terrestrial vertebrates Today they are increasingly depleted and believed to contain about 60% of the world's plant, bird, mammal, reptile, and amphibian species Threats to Biodiversity Habitat Loss Over-exploitation Pollution Invasive species Climate Change Habitat Loss Threats to Biodiversity Habitat Loss Changes in land use by humans Growing cities / urban sprawl Expansion of farmland / habitat fragmentation Draining wetlands Habitat Fragmentation Larger habitats become divided into smaller sections by highways, roads, farms, urbanization, etc. Over-exploitation Threats to Biodiversity Over-exploitation Over-hunting eg. Dodo bird hunted to extinction Over-fishing eg. in 1992 it became illegal to catch Atlantic cod Deforestation See Relentless consumption eg. The average Canadian ecological footprint may be around 7 or 8 times larger than the footprint of countries in the developing world Pollution Threats to Biodiversity Pollution Pollutant are chemicals with known toxic effects on one or many species Human activity has introduced waste products and contaminants throughout the biosphere Air, land and water have been affected nearly everywhere Egs. Industrial waste, municipal waste, pesticides, sewage containing hormones, heavy metals, pharmaceuticals, etc. Invasive Species Threats to Biodiversity Invasive species Non-native species of plants and animals that establish in new habitats These may disrupt local ecosystems and/or displace local species causing extinction or population reduction Eg. in Canada: purple loostrife, mountain pine beetle, asian longhorned beetles, zebra muscles Eg. in Australia: prickly pear cactus, cane toads, feral pigs, red foxes, european rabbits, camels Climate Change Threats to Biodiversity Climate Change Rapid disruption of ecosystem stability Changes in global geography (eg. melting of permafrost) Unpredictable changes to ecosystems around the world Biodiversity Hotspots 34 identified regions of particularly large plant diversity which are under particularly strong threats of habitat loss (at least 70% lost of original habitat) Established in 1999 Some estimated that they contained 44% of earths plant species and 35% of terrestrial vertebrates They covered about 11.8% of earths land surface Now they have been reduced to only about 1.4%