INTERFACE working package B
C-sequestrationby Peter Müller |
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The response of blue carbon accumulation to shifts in species composition and different habitat-management practices |
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An important ecosystem service provided by salt marshes is C-sequestration. Compared to other wetland types (e.g. peatlands), salt marshes can act as particularly effective C-sinks, as C-sequestration in these systems does not solely rely on reduced decomposition rates, but also on high productivity and the burial of organic matter in sediments. Thus, the role of salt marshes and other coastal ecosystems in the global C-cycle has recently gained increasing attention. The organic C stored in coastal ecosystems such as tidal marshes, seagrass meadows and mangroves is referred to as “blue carbon”. While first global estimates on the C-storage potential of salt marshes as blue carbon systems mainly rely on data from studies conducted in North America, relatively little is known about C-sequestration in European salt marshes and Wadden Sea salt marshes, in particular. In work package B of the INTERFACE project, we aim at quantifying rates of C-sequestration in Wadden Sea salt marshes. We want to assess the impact of different hydrological conditions (naturally vs. artificially drained marshes), soil compaction (caused by livestock grazing) and species composition (particularly with regard to the spread of the native grass Elymus athericus) on C-sequestration and organic matter decomposition. In three different studies, we are aiming to answer the following questions:
B.1) An inventory of C-sequestration and C-allocation (field study)
B.2) Quantifying in situ organic matter decomposition and belowground C input (field study)
B.3) Ecosystem CO2 fluxes – a factorial experiment To support the findings of the correlative field studies and to answer the above mentioned questions under controlled conditions, a three-factorial experiment (compaction, drainage, species composition) is conducted in a large tidal basin setup at the Biocenter Klein Flottbek. By measuring ecosystem CO2-fluxes (net CO2-uptake and ecosystem respiration) as well as microbial activity and abundance, we will be able to answer the question how these three factors affect the autochthonous C-balance of salt marsh ecosystems. |