What is the main function of primary producers in an ecosystem?

The primary function of primary producers in an ecosystem is to create their own food through the process of photosynthesis or chemosynthesis. They convert sunlight or chemical energy into organic matter, which serves as the foundation for energy flow in food webs. This ability to produce their own food distinguishes them from other organisms in the ecosystem, such as consumers and decomposers.

While options such as recycling nutrients and supporting herbivores are important ecological processes, the central role of primary producers lies in their capacity to convert inorganic materials into organic compounds, ultimately sustaining the entire ecosystem by providing energy-rich compounds that are utilized by various levels of consumers. Thus, making their own food is a fundamental characteristic that reinforces their role as primary producers.