Freshwater ecosystems and marine ecosystems are quite different from each other. They have unique features, different kinds of living things, and play special roles in our world. Here are some important differences:
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Salt Levels:
- Freshwater ecosystems, like rivers, lakes, and wetlands, have very low salt levels. The salt is usually less than 0.5 parts per thousand.
- Marine ecosystems, which include oceans and seas, have much higher salt levels, averaging around 35 parts per thousand.
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Variety of Life:
- Freshwater areas are home to about 6% of all the species in the world, but they only cover about 0.8% of the Earth’s surface.
- Marine ecosystems, on the other hand, support over 230,000 known species. Some scientists believe there could be millions of species we haven't discovered yet.
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Amount of Water:
- Freshwater makes up about 2.5% of all the water on Earth. However, only 1% of this freshwater is available for people to use.
- In contrast, marine ecosystems cover about 71% of the Earth's surface and hold about 97.5% of the planet's water.
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Productivity:
- Freshwater ecosystems usually produce less food for living organisms. They average around 10 to 20 grams of carbon per square meter each year.
- Marine ecosystems can be very productive, especially in some areas where upwelling occurs. In these areas, productivity can be over 200 grams of carbon per square meter each year.
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Ecological Roles:
- Freshwater ecosystems are super important for cleaning water, controlling floods, and recycling nutrients.
- Marine ecosystems play a crucial role in regulating the global climate. They also produce more than 50% of the oxygen in our atmosphere and help absorb carbon from the air.
These differences show how each type of ecosystem is important and has special functions that help our planet.