Ecology Flashcards
(19 cards)
Components of an Ecosystem?
Biotic and Abiotic Factors
Biotic Factors - examples and definition
A biotic factor is a living organism that shapes its environment; animals, birds, plants, fungi, and other similar organisms.
Abiotic Factors - examples and definition
An abiotic factor is a non-living part of an ecosystem that shapes its environment; temperature, light, and water.
How does energy flow through ecosystems
Energy is transferred between organisms in food webs from producers to consumers.
How is matter recycled in ecosystems
Decomposers release nutrients when they break down dead organisms. nutrients are taken up by plants through their roots. nutrients pass to primary consumers when they eat the plants.
Mutualism
Both species benefit from interaction
Commensalism
One species benefits, one unaffected
Competition
Each species affected negatively
Predation, parasitism, herbivory
One species benefits, one is disadvantaged
What are keystone species in food webs?
A keystone species is an organism that helps define an entire ecosystem. Without its keystone species, the ecosystem would be dramatically different or cease to exist altogether.
Analyse how changes in abiotic and biotic factors can affect population sizes within an ecosystem?
Biotic factors such as predation and lack of vegetation control, If food sources (plants and flesh) are very scarce, organisms are going to starve and die. This will decrease the population of species in an ecosystem.
What factors affect population sizes such as seasonal changes?
Factors such as latitude, altitude and proximity to the coastline affect the extent of the seasonal fluctuations.
What factors that affect population sizes such as destruction of habitats?
Geological processes, climate change, introduction of invasive species, ecosystem nutrient depletion, water and noise pollution are some examples.
What factors that affect population sizes such as introduced species?
The abundance of environmental resources such as food, water, and space determines how population abundance changes over time.
How do ecosystems change because of events such as bushfires?
Fires can also free these plants from the competition with invasive weeds and eliminate disease or droves of insects that may have been causing damage to the old growth.
How do ecosystems change because of events such as drought?
Drought conditions can negatively alter aquatic ecosystems, with immediate effects on fish and invertebrate species, such as fish kills in reservoirs.
How do ecosystems change because of events such as flooding?
These can degrade aquatic habitats, lower water quality, reduce coastal production, and contaminate coastal food resources.
How are ecosystems in Australia affected by human activities?
Global population growth contributes to the; destruction, modification and fragmentation of wildlife habitat, reduced genetic diversity, the spread of exotic and invasive species, air, noise and light pollution, fire regimes, and a rapidly changing climate
What is the impact of human behaviour upon ecosystems?
Humans impact the physical environment in many ways: overpopulation, pollution, burning fossil fuels, and deforestation. Changes like these have triggered climate change, soil erosion, poor air quality, and undrinkable water.
