Primary production refers to the process by which autotrophs, such as plants and algae, convert light energy into chemical energy through the process of photosynthesis. This transformation results in chemical energy that fuels the organism’s metabolism and supports growth. Primary production serves as the cornerstone of all food webs and ecosystems, supplying the energy and nutrients essential for the survival of all other organisms.

In contrast, secondary production is the generation of biomass by heterotrophs. Heterotrophs, including animals, consume organic matter produced by autotrophs or by other heterotrophs, converting this organic material into their own biomass. This biomass is then utilized to sustain the organism’s metabolic processes and facilitate growth. Secondary production is inherently dependent on primary production, as it relies on the availability of organic matter generated by autotrophs. A deeper understanding of this relationship can illuminate the constraints on primary production that subsequently impact secondary production.

To summarize, primary production involves the conversion of sunlight into energy through photosynthesis by plants and algae, establishing the foundational layer of all food webs. Secondary production occurs when animals feed on these plants (or other animals) and assimilate this food into their own body mass. In essence, primary production creates the food supply, while secondary production involves the consumption and transformation of that food for growth. Both processes are vital for maintaining ecosystem balance. For further insights into the broader implications of these processes, please refer to our notes on the subject. Additionally, we will explore practical applications of understanding biomass production and its significance in ecological contexts.