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Natural versus artificial ecosystems.
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An ecosystem can be defined as a large, highly interconnected area of the planet that is composed of several different biotic and abiotic components.
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A good example of an ecosystem would be an entire forest or a mountain range.
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In this video, we will look at the difference between natural and artificial ecosystems.
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Natural ecosystems have been around as long as the planet itself.
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A natural ecosystem is made up of all the plants, animals, and, environmental features in an area.
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Generally, natural ecosystems have what are called autochthonous resource inputs.
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It is just a scientific way of saying that most, if not all, of the components found within an ecosystem are indigenous or native to that area.
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All of these components interact through various nutrients and energy cycles to create large and incredibly complex webs.
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Sometimes these webs contain over 100 different components and span thousands of kilometers.
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So overall, natural ecosystems consists of many species of plants and animals and have long and complex food webs and have high genetic diversity.
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They are also naturally sustainable.
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Artificial ecosystems have been created or altered by humans and are not necessarily found in nature.
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Farms are an example of an artificial ecosystem.
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Based on the complexity of natural ecosystems, how many components do you think artificial ecosystems have?
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Pause and have a think.
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If you guessed somewhere between five and ten, you're pretty close to the average.
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In contrast to natural ecosystems, artificial ecosystems are often designed to be very simple.
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Artificial ecosystems may only contain a few (3 or 4) different components and usually require allochthonous or external resource inputs
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i.e. they contain species and inputs that are not native.
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As a result of their simplicity, an artificial ecosystem cannot function like its natural counterpart and there is incomplete nutrient recycling.
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Hence extra resources are required for the ecosystem to continue functioning.
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Genetic diversity is very low in artificial ecosystems and food webs are very simple or even incomplete due to killing of pest species.
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Another important difference between natural and artificial ecosystems is the time scale used to measure the activity within each ecosystem.
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For example, water cycling in natural ecosystems generally requires decades or centuries for the water to complete a full cycle and return to the designated starting point.
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In an artificial ecosystem, on the other hand, the entire water cycle may only take a few weeks or months before it's returned to its starting point.
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The massive difference in time scale is due to both the small size and relative simplicity of artificial ecosystems.
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They are easier to control and can easily be designed for high productivity.
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The productivity in natural ecosystems is much more variable and depends on the environment.
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So from this video, you should know some crucial differences between natural and artificial ecosystems.
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Most importantly, natural ecosystems are much more complex and diverse,
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whereas artificial ecosystems are much simpler and can be easily controlled for high productivity.