Helsingin yliopisto, Bio- ja ympäristötieteellinen tiedekuntaUniversity of Helsinki, Faculty of Biological and Environmental SciencesHelsingfors universitet, Bio- och miljövetenskapliga fakultetenVesanen, Anna-Roosa2023URN:NBN:fi:hulib-202306132578http://hdl.handle.net/10138/358755Coastal habitats contribute significantly to global carbon cycling. These ecosystems store carbon into the sediment and provide a crucial ecosystem service of sequestering carbon from atmosphere. In situ carbon degradation assessment methods in coastal sediments have not been widely developed. A novel, cost-effective method for assessing degradation rates, ROMA (rapid organic matter assessment), has been developed recently, but it has not been tested yet in cool, shallow subtidal coastal areas. In this Master’s thesis, the aim is to test the ROMA methodology in shallow coastal habitats in Northern Baltic Sea. To investigate the method, following research questions were studied: (1) can carbon degradation be assessed by using the ROMA- method in the shallow coastal habitats, (2) whether carbon degradation rates differ between two sites with varying sediment characteristics, (3) how various diversity metrics and environmental context can be linked to carbon degradation rates. Results of this study show that ROMA method is feasible to assess carbon degradation rates in shallow coastal areas. There was a difference in the degradation rates between the study sites with different environmental characteristics, but the driver for the carbon degradation still seemed somewhat unclear. The methodology should be developed and trialled further, as it is promising cost-effective way to measure carbon degradation in situ.engcarbon degradationrapid organic matter assessmentROMAcoastal ecosystemspro gradu -tutkielmatYmpäristömuutosEnvironmental ChangeMiljöförändringYmpäristömuutoksen ja globaalin kestävyyden maisteriohjelma (ECGS)Master's Programme in Environmental Change and Global SustainabilityMagisterprogrammet i miljöförändringar och global hållbarhet