THE ROLE OF SMALL AQUATIC SYSTEMS IN CARBON SEQUESTRATION – Northumbria University, Newcastle upon Tyne

Summary

Small lakes and ponds are often omitted from global carbon budgets yet recent evidence has shown they represent a disproportionately active component of the freshwater carbon cycle that combined with their overall extent means they are likely to play a significant global role in the sequestration of organic carbon.

The project will continue our group’s work on characterising carbon mass balances from such systems, including CO2 fluxes and organic carbon burial rates. We are particularly interested in how such processes respond to climatic variations, extreme weather events productivity and pond successional stage. We are keen to estimate the potential role of small aquatic systems in providing a buffering effect during periods of sustained climatic change; specifically, how in wetter periods, their greater overall extent might lead to increased carbon sequestration, and potential increases in emissions during drought.

The main study area will be a group of natural and constructed ponds in Northumberland, UK, though it is likely that the approaches developed during the project will be extended to natural and constructed wetland sites in other parts of the UK and also to some European sites. A major part of the work will involve the development of a technique to estimate carbon burial rates in ponds at a fine temporal resolution, utilising pollen signals from nearby arable rotations to date sediment strata. Carbon dioxide fluxes will be measured using floating chambers and an infra-red analyser, allowing uptake and evasion to be estimated for a wide range of climatic conditions, including during drying and rewetting phases. The data will be used to refine our understanding of overall fluxes from small aquatic systems and, in combination with GIS data, used to model the overall sequestration rates on regional scales and how this might change during different climatic conditions.

More information here.