Question: Where does the flow of energy in an ecosystem begin?
Disambiguated questions and answers: question: Where does the flow of energy in an ecosystem originate?|Where does the flow of energy in an ecosystem start?|Where does the flow of energy begin in an ecosystem?
Where is the first step in the flow of energy in an ecosystem when it reaches earth??
answer: the Sun
Solar Energy
Solar energy is fixed by the photoautotrophs
Photosynthesis
Natural Questions answer: Solar energy (from the Wikipedia article "Energy flow (ecology)")