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1.2 Ecosystems Ecosystem a part of a biome in which abiotic (non-living) factors interact with biotic (living) componentsEcosystem a part of a biome in which abiotic (non-living) factors interact with biotic (living) components Can be many hectares of land, or the size of an old log. Within an ecosystem, there are many habitats.Within an ecosystem, there are many habitats. The habitat of the red fox often includes the edges of forests or marshlands Slide 2 Abiotic Interactions in Ecosystems It is the abiotic components that allow the biotic components to survive in an ecosystem.It is the abiotic components that allow the biotic components to survive in an ecosystem. Abiotic factors include : Oxygen - produced by green plants & micro- organisms.Oxygen - produced by green plants & micro- organisms. Water - necessary for all life.Water - necessary for all life. Nutrients - for growth.Nutrients - for growth. Light - required forLight - required forphotosynthesis. Soil - contains water &Soil - contains water &nutrients. Slide 3 Biotic Interactions in Ecosystems Community: all organisms that interact within an ecosystem.Community: all organisms that interact within an ecosystem. Population: all members of a certain species within an ecosystem.Population: all members of a certain species within an ecosystem. Species: all organisms within an ecosystem that have the same structure & who canSpecies: all organisms within an ecosystem that have the same structure & who can reproduce with each other (and produce fertile offspring). Slide 4 Species can have many types of relationships in a population.Species can have many types of relationships in a population. Symbiosis refers to the interaction between the members of two different species. Commensalism - one species benefits, one is not affectedCommensalism - one species benefits, one is not affected For example, the barnacles on a whale Mutualism - both species benefitMutualism - both species benefit For example, a bee gathering nectar from a flower Parasitism - one species benefits, the other is harmedParasitism - one species benefits, the other is harmed For example, hookworm living in dogs Slide 5 Niches, Competition and Predation Niche: the role an organism has within an ecosystem.Niche: the role an organism has within an ecosystem. also refers to the environment in which a species prospers Competition: occurs when a limited resource is desired by 2Competition: occurs when a limited resource is desired by 2 or more individuals in a niche. this limits the size & health of individual organisms, & perhaps the population. Predation: the relationship between thePredation: the relationship between the eaters & the eaten. Predators have adaptations to help them catch prey. Prey have adaptations to help avoid predators. Eg. spines & shells, camouflage and mimicry.Eg. spines & shells, camouflage and mimicry. Slide 6 Biodiversity in Ecosystems Biodiversity: the variety & number of different individuals & species in an ecosystem.Biodiversity: the variety & number of different individuals & species in an ecosystem. Healthy ecosystems generally have high biodiversity. Most biodiversity losses occur from the loss of habitat. Humans often have a negative impact on biodiversity. Ecological management programs try to balance human progress with maintaining biodiversity. Take the Section 1.2 Quiz