Presentation on theme: "Topic 2 - Biotic and Abiotic Influences on Terrestrial and Aquatic Ecosystems."— Presentation transcript:
Topic 2 - Biotic and Abiotic Influences on Terrestrial and Aquatic Ecosystems
Limiting Factor = any factor that limits the size of a population or where it can live Tolerance Range = the range of abiotic conditions which a species can survive Biotic and Abiotic Influences on Ecosystems
Examples of how humans affect abiotic factors in a terrestrial ecosystem: Light – Cutting trees to expose plants underneath to more light Water – Damming rivers decreases water available – Irrigating fields increases water available in an ecosystem Abiotic Limiting Factors – Terrestrial
Temperature – Global warming reduces habitat for animals adapted to cold temperature Nutrients – Adding fertilizer to soil increases available nutrients
Examples of how humans affect abiotic factors in an aquatic ecosystem: Light – Stirring up sediment at the bottom of a lake decreases amount of light reaching plants Salinity (Salt Levels) – Run-off from salting high ways in the winter increases salt concentration in rivers and lakes Abiotic Limiting Factors – Aquatic
Temperature – Industries release heated water into lakes and rivers killing fish and other organisms Nutrients – Fertilizer can run-off causing algal blooms Acidity – Burning of fossil fuels creates acid rain which makes bodies of water more acidic
Examples of biotic factors in ecosystems: – Competition Organisms compete for the same limited resources: food, water, habitat, light, mates – Predation Predator (the organism that hunts) kills and eats its prey (the organism that is attacked) The populations of the predator and prey depend on each other (more on this topic next day…) Biotic Limiting Factors – Species Interactions
Lynx and a hare Indian python attempting to swallow a deer A male lion with his cub eating a water buffalo Praying Mantis eating a grasshopper INSERT VIDEO LINK
Symbiotic Relationships between organisms: Mutualism (+ and +) Two organisms benefit from each other Commensalism (+ and 0) One organism benefits and the other neither benefits nor is harmed Parasitism (+ and -) One individual lives on or in a host organism and feeds on it Biotic Limiting Factors – Species Interactions Flower provides the bee with nectar, the bee helps the flower spread its pollen Orchids grow on the trunks or branches of trees to receive more light. As long as the plant is not too heavy, the tree is not affected. The cowbird lays their eggs in the nests of other birds (like the reed warbler). The reed warbler mother must spend more time feeding the larger and more demanding cowbird
Mutualism (+ and +) Stinging anemone tentacles provide the clownfish with protection from predators. The clownfish defend anemones against butterflyfish which eat the anemones. Bacteria live in the nodules of legumes (ex. soybeans) and provide nitrogen for the plant. The plant provides sugars for the bacteria.
Cleaner wrasses and whale shark Egyptian Plover and Nile crocodile Red-billed oxpecker and the Impala Cow (or other ungulates) and E.coli bacteria
Commensalism (+ and 0) Ramora gets free ride + food Shark and a remora fish Buffalo and Cattle Egrets Whales and barnacles
Parasitism (+ and -) Parasite receives nourishment from host – Parasites don’t normally kill host but the host is harmed A roundworm inside a person’s eye… EWWW!!! Numerous roundworms from the bowel of a dog post-surgery…. DOUBLE EWWW!!
Bed bugs… inside a mattress… do you see the bed bug fecal matter?!? EW! Caribbean soldierfish host to a parasitic isopod, which feeds on its body tissues Human head lice feeds on blood from the scalp