Can an ecosystem survive without consumers?
No ecosystem cannot survive without consumers.
A consumer is a heterotroph that cannot make its own food and eat producers or other organisms for energy. We are in the category of consumers that eat the food that producers like plants made.
Consumers in an ecosystem balance the food chain by keeping plant populations in a limited number. Without proper balance, an ecosystem would collapse and it will decline all the affected populations.
Therefore, without consumers ecosystem cannot function.
If any level is removed from the food chain, all other levels will be affected automatically.
Example: Without consumers, producers have no predator and thus their growth will be more and higher level consumer which depends on these consumers will also die. For illustration, if consumer such as deer is removed then producer such as plants or grass growth will be more and it covers large area. Also, tigers who kills deer for food will die out due to lack of food. Thus, by removing one level of a food chain will ultimately affects all other levels.