Limiting Factors Notes

2.3 Interactions and Changes in Ecosystems

·        Limiting factors control or limit the number and health of biotic elements in ecosystems

·        Examples of limiting factors are the amount of food, water, energy, oxygen, and suitable habitat available to organisms

·        Other limiting factors can include; predators, hunting,  or natural or human made disasters

·        Availability of limiting factors can change in ecosystems; e.g., when higher rainfall increases the number of producers and then the consumers have more food

·        Sometimes changes can negatively impact availability of limiting factors; e.g., a forest fire or bioinvasion

·        Bioinvasion is when a foreign species is introduced into native ecosystems

·        A native species occurs naturally in a given area e.g., trout in Lake Ontario

·        An introduced species is one that is brought to an environment where it did not live before e.g., zebra mussels in Lake Ontario

·        Introduced species with no natural predators can quickly multiply and take over habitat and deplete the food source of native species

·         Zebra mussels and Asian carp are known as invasive species

·        Competition – all living things in a community compete for resources like food, water, and habitat; however, the supply of these resources are limited

·        Living things are always struggling to meet their basic needs at the expense of other living things