Abstract
Lakes are important habitats for biogeochemical cycling of carbon. The organization and structure of aquatic communities influences the biogeochemical interactions between lakes and the atmosphere. Understanding how trophic structure regulates ecosystem functions and influences greenhouse gas efflux from lakes is critical to understanding global carbon cycling and climate change. With a whole-lake experiment in which a previously fishless lake was divided into two treatment basins where fish abundance was manipulated, we show how a trophic cascade from fish to microbes affects methane efflux to the atmosphere. Here, fish exert high grazing pressure and remove nearly all zooplankton. This reduction in zooplankton density increases the abundance of methanotrophic bacteria, which in turn reduce CH 4 efflux rates by roughly 10 times. Given that globally there are millions of lakes emitting methane, an important greenhouse gas, our findings that aquatic trophic interactions significantly influence the biogeochemical cycle of methane has important implications.
| Original language | English |
|---|---|
| Article number | 8787 |
| Journal | Nature Communications |
| Volume | 6 |
| DOIs | |
| State | Published - Nov 4 2015 |
Funding
The research was funded by Academy of Finland grant 137671 to RIJ. The authors are indebted to the staff at Lammi Biological Station, University of Helsinki, for providing analysis and support in the field and the laboratory. We are grateful for the help of J. Vesterinen and J.C. Zuniga in the field. We also appreciate the expertise and assistance of M. Rask, S. Vesala and K. Määttänen from the Finnish Game and Fisheries Research Institute. Comments by J. Stanford, B. Ellis and G. Luikart greatly improved this manuscript.
| Funders | Funder number |
|---|---|
| Academy of Finland | 137671 |
