Mesocosm

A mesocosm is a small ecosystem created by people for the purpose of scientific research. Mesocosms include all the elements of ecosystems but on a smaller scale. Scientists use mesocosms to study many features, including climate change and ecology. A mesocosm is self-sufficient, and it includes all the parts of a natural ecosystem, just on a smaller scale. Mesocosms can be very small, such as a table-top terrarium. They can also be fairly large, such as a water tank as large as a swimming pool.

Background

Mesocosms are essentially smaller, human-made ecosystems. Because of this, mesocosms have a lot in common with ecosystems. Ecosystems are made up of living things, nonliving things, and the interactions among all the different elements in a particular environment. Ecosystems can be small, such as a pond, or large, such as an ocean. Living things in ecosystems rely on one another. They also rely on the nonliving parts of the ecosystem. In turn, the living things help renew the nonliving things in the environment. The living things in an ecosystem include plants, animals, and other organisms. The nonliving things include rocks, humidity, and temperature. All things in an ecosystem are dependent on one another. For example, a change in temperature could kill off some plants in an ecosystem. Some animals that eat those plants for food might die because they do not have enough to eat.

Ecosystems have to have an energy source. The sun is the energy source for all ecosystems on Earth. It provides energy to producers, which are organisms such as plants that make their own food. The producers use the energy from the sun to make their food. Then, they became an energy source for consumers, which are living things that eat other things for energy. Ecosystems also have decomposers, which are organisms that break down waste material, such as dead plants. Producers, consumers, and decomposers are all vital to an ecosystem. Mesocosms, because they are small versions of ecosystems, also have to have all of these elements to survive independently.

Overview

Mesocosms are used by scientists to conduct research. Scientists use these small, contained ecosystems for research to help them control much of what goes into and what happens in the system. Mesocosms can be closed systems or open systems. In a closed system, the mesocosm is cut off from the outside and sealed shut. The only input from the outside is sunlight because all ecosystems need an energy source. The closed mesocosm has all the other elements—including the producers, consumers, and decomposers—that it needs. If the mesocosm does not have all of these elements, it will not survive. Because of this, closed systems are harder to make and maintain.

Scientists and researchers make mesocosms. They make different types of mesocosms for different needs. Scientists making mesocosms decide the type of system and container they want to use before making it. Scientists make aquatic or terrestrial mesocosms, depending on what they want to study. Aquatic mesocosms help scientists study the oceans, lakes, ponds, and other aquatic ecosystems. Terrestrial mesocosms help scientists study land-based ecosystems.

Scientists also have to choose containers and locations for their mesocosms. The container can be made from many different types of materials. Some are made of natural substrates. Others are made from human-made materials, such as stainless steel or fiberglass. The material being used will depend on whether the mesocosm will be aquatic or terrestrial. It also depends on whether the system will be open or closed and what types of living things will be included in the mesocosm. Scientists can form mesocosms in tanks, bags, ponds, and other containers, depending on their needs.

After choosing a type of mesocosm, a location for it, and a container, scientists have to create the mesocosm by adding the living and nonliving elements of the ecosystem. The living elements include the water and dirt in the mesocosm because they include so many microorganisms that are vital for an ecosystem’s survival. Because of that, scientists often take water and dirt for their mesocosms from the natural environments they want to recreate for their research. Scientists also have to find the correct balance of producers, consumers, and decomposers. For example, a scientist could not add a large consumer, such as a fish, to an aquatic mesocosm without having enough producers to support the fish. The fish would die, and the mesocosm would not be successful, if the scientist did not find the correct balance. For that reason, many mesocosms include mostly small organisms that do not need large amounts of food to survive. Scientists also have to add nonliving materials, such as rocks, to the mesocosm.

Even though creating mesocosms takes a great deal of time and effort, scientists make them because they are useful tools for scientific experimentation. Mesocosms are beneficial because they help researchers control the environment and replicate experiments. An experiment conducted in nature might be difficult to replicate because nature has more variability. Mesocosms are useful in part because they are controlled. Researchers can replicate mesocosms that are, if not exactly the same, extremely similar. Scientific experiments must be repeatable and replicable to be reliable. Therefore, mesocosms are ideal for scientists. To conduct experiments, scientists often create multiple similar mesocosms and add different variables to each system. The scientists observe and record the differences among the mesocosms to understand how the variables affect life in the particular ecosystem.

Although mesocosms make experiments more reliable, they are not perfect. It would be difficult for scientists to replicate every single element of a mesocosm. Therefore, mesocosms that include the same elements will likely have some variables that differ slightly from one another. Another drawback of mesocosms for research is that some organisms might respond differently in an enclosed environment than in nature. For example, scientists have found that phytoplankton in enclosed environments behave differently from phytoplankton living in nature.

Bibliography

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