Search results for "cane sugar"

Whole-Lake Sugar Addition Demonstrates Trophic Transfer of Dissolved Organic Carbon to Top Consumers

2017

Terrestrial dissolved organic carbon (DOC) provides an external carbon source to lake ecosystems. However, there is ongoing debate about whether external DOC that enters a lake can pass up the food web to support top consumers. We show, from experimental manipulation of a whole lake, that externally loaded DOC can contribute appreciably to fish biomass. Monthly additions of cane sugar with a distinct carbon stable isotope value during 2 years rapidly enriched the 13C content of zooplankton and macroinvertebrates, with a more gradual 13C enrichment of fish. After sugar addition stopped, the 13C content of consumers reverted towards original values. A simple isotope mixing model indicated tha…