What are the main trophic levels in an ecosystem?

The main trophic levels in an ecosystem are characterized by the various roles organisms play in energy transfer and nutrient cycling. Producers are the foundational level, consisting of autotrophs like plants, which convert sunlight into energy through photosynthesis. They form the base of the food web.

Following producers are primary consumers, typically herbivores that directly consume plants. Then come secondary consumers, which are carnivores that eat the primary consumers. Additionally, detrivores—organisms that feed on decomposing organic matter—play a crucial role, breaking down dead material and recycling nutrients back into the ecosystem.

This structure is represented in option D, where detrivores are included, emphasizing the importance of decomposition and nutrient cycling. Understanding these roles helps to illustrate the flow of energy and matter through an ecosystem, showcasing the interconnectedness of various life forms and their contributions to ecological balance.