Final answer:
Artificial ecosystems are not self-sustaining due to their isolation from the natural environment and lack of necessary elements like nutrients, sunlight, and oxygen.
Step-by-step explanation:
Artificial ecosystems are not self-sustaining because they are often isolated from the natural outside environment, allowing only select species to be present. This means that organisms or nutrients that might be required for self-sustaining life are typically missing. For example, in a closed terrarium, plants may not have access to necessary nutrients from decomposing matter or the water cycle, leading to a limited ability to sustain life. Another reason is that artificial ecosystems start out without the necessary elements needed to survive, such as sunlight and oxygen. Without these essential components, the ecosystem cannot sustain life over the long term.
Learn more about Artificial ecosystems