Accounting for plankton metabolism in the carbon cycle of lakes
The Earth’s surface waters have long been thought to perform a vital ecosystem service by absorbing atmospheric carbon dioxide (CO2), but inland waters in fact release 1-2 billion tons of C each year as CO2. Concerns have been raised that these emissions are in part due to human disturbance, as most types of land uses leak reactive dissolved organic carbon (DOC) into freshwaters. However, the contributions to the emitted CO2 by plankton communities that degrade such DOC remain unresolved. This work uses a new measurement technique to unravel the true role of freshwater planktons in the carbon cycle. Aims are to: (1) Disentangle the role of the plankton community from other CO2-releasing processes in aquatic ecosystems, by using novel automated chambers to directly measure planktonic metabolism; (2) Constrain the critical parameter RQ (respiratory quotient; CO2 per unit O2 use), known to vary widely yet assumed to be fixed around 1 by current models. The overall goal is to provide improved estimates of the quantitative role that freshwater plankton communities play in the carbon cycle of different types of lakes. More importantly, the project may contribute to a break-through in the mechanistic understanding of the substantial greenhouse gas emissions that result from anthropogenic DOC loading.
|Effective start/end date||2016/08/15 → 2018/12/31|
Related research output
In situ plankton community respiration measurements show low respiratory quotients in a eutrophic lakeMünzner, K. & Martin Berggren 2018 1 p.
Research output: Contribution to conference › Abstract