* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download Examples - 9thlawofscience
Island restoration wikipedia , lookup
Introduced species wikipedia , lookup
Unified neutral theory of biodiversity wikipedia , lookup
Ecological fitting wikipedia , lookup
Overexploitation wikipedia , lookup
Latitudinal gradients in species diversity wikipedia , lookup
Biological Dynamics of Forest Fragments Project wikipedia , lookup
Operation Wallacea wikipedia , lookup
Ecosystem services wikipedia , lookup
Ecological resilience wikipedia , lookup
Conservation biology wikipedia , lookup
Natural environment wikipedia , lookup
Ecological succession wikipedia , lookup
Biodiversity wikipedia , lookup
Human impact on the nitrogen cycle wikipedia , lookup
Restoration ecology wikipedia , lookup
Habitat conservation wikipedia , lookup
Theoretical ecology wikipedia , lookup
Biodiversity Equilibrium Succession Biodiversity Species at risk Human Impact Equilibrium When biotic and abiotic features remain constant over time On a large scale, healthy natural ecosystems are in a state of equilibrium E.g. biomes maintain characteristics On a small scale, ecosystems are in a constant state of change E.g. forest fire, disease outbreak Ecological Succession Process of establishing and replacing a community following a disturbance Primary succession: occurs on soil or bare rock where no life previously existed E.g. following a volcanic eruption, sandy shores of coastline Secondary succession: follows a disturbance that disrupts but does not destroy the community E.g. regrowth after forest fire http://zoology.muohio.edu/oris/ZOO121/notes/graphics/ch04/fig4_24.jpg http://www.geographyalltheway.com/ib_geography/ib_ecosystems/imagesetc/ecological_succession.jpg Pattern Coloniser: Lichen, moss Pioneer Community: Small, hardy plants (e.g. grass) Shrubs & small trees Climax community: Forest (large trees) reached equilibrium Benefits of Succession Helps ecosystem maintain long-term sustainability Biodiversity . the number and variety of species in an ecosystem important for maintaining a stable population Species richness: measurement of species numbers Biodiversity Case: The Irish potato famine resulted in great hunger because the potato was such an important crop. Today, people in developed countries have a lot of food choices so they are able to meet their nutritional needs. Analysis Question Ecosystems with HIGH biodiversity Ecosystems with LOW biodiversity Analysis Question Ecosystems with HIGH biodiversity Rain forests and oceans, coral reef both have warm temperatures, regular, precipitation, abundant food supply In general, ecosystems closer to the equator are more rich. (little to no pollution or disturbance) Ecosystems with LOW biodiversity The Arctic tundra and the desert both have extreme temperatures and short growing seasons for plants at the first trophic level In general, ecosystems with extreme physical conditions are less rich Ecotone Organisms often move from one ecosystem to another. An ecotone is a transition area between two ecosystems that includes members of the community of both ecosystems. Ecotones often have a lot of biodiversity. Monoculture A monoculture is an ecosystem in which there is only one plant often created by humans in agriculture Example: a wheat field Problems with Monocultures More susceptible to pest infestation than natural ecosystems Invaders do not have to search for food and can multiply uncontrollably. All it takes is one invader who is resistant to pesticides and the whole monoculture ecosystem can be destroyed by the invader. Monoculture Advantages of monocultures Disadvantages of monocultures Monoculture Advantages of monocultures - increased food production - can adjust farming conditions in the field to maximize production (irrigation, fertilization) - easier to harvest if all the plants are in one area Disadvantages of monocultures - decreased biodiversity and damages the environment - pests can multiply in the absence of their natural predators Extinction A natural process Usually caused by catastrophic event (e.g. asteroid, volcano) Human activity has increased rate of extinction Species at Risk When a population's size declines below a critical level, the species will not longer be able to fill it ecological niche COSEWIC: Committee on the Status of Endangered Wildlife in Canada Responsible for categorizing species into atrisk categories RENEW: Recovery of Nationally Endangered Wildlife Responsible for preparing action plans to ensure recovery of endangered or threatened species Species at Risk classifications Classification Definition Extinct Species no longer exists Extirpated Endangered Threatened Special concern Example Passenger pigeon Species no longer exists in the wild in Atlantic a specific area but live elsewhere walrus Species in imminent danger of going Barn owl extinct or becoming extirpated Species likely to become endangered Humpback if current trends and conditions whale continue Species may become threatened or Polar bear endangered because of a combination of factors Artificial ecosystem Natural ecosystem Definition An ecosystem planned or maintained by humans. Members of this ecosystem are free to interact with the physical and chemical environment. Examples Parks, gardens, farms, schoolyard Lakes, rivers, deserts, forests, meadows