Which food chain is based on living plant biomass?
A grazing food chain draws its immediate energy from living plant or algal biomass. Herbivores consume producers, carnivores consume herbivores, and waste or dead tissue connects the chain to decomposers. In contrast, the detritus pathway begins with nonliving organic matter, even though that material ultimately arose from primary production. The distinction concerns the first consumer resource, not separate energy origins. Ecosystems contain both routes, and their relative importance depends on plant defenses, tissue turnover, climate, and consumer access. Quantitative interpretation requires
Ref: Fundamentals of Ecology, Odum & Barrett, 5th Ed., Ch. 3