VILKEN STRANDVEGETATION BIDRAR TILL DET ORGANISKA MATERIALET I KUSTNÄRA SEDIMENT? Kolsänkor/källor, nedbrytbarhet och eDNA spårning

Abstract

Coastal sediments are important carbon sinks, storing organic matter and thereby helping to reduce the amount of greenhouse gases in the atmosphere. However, they can also act as carbon sources if the deposited organic matter decomposes rapidly, contributing to increased greenhouse gas emissions and global warming. Rapid decomposition partly depends on the degradability of the material itself. In this literature review, I examine which coastal plant species dominate different locations along the Swedish coast, based on coverage data from the ClimScape project (www.climscape.se). For the most dominant species, I investigated the type of organic matter they may contribute to the sediments and based on those results I qualitatively assessed which sites that may function as carbon sinks or sources. The only two sites that showed a certain tendency to act as carbon sources were the forested wetlands in Råneå, Luleå and Björköfjärden, Sundsvall. The most dominant plant species here were composed of more labile organic matter. If this material contributes to the organic stocks in the sediments, it could increase sediment degradability and potentially shift these areas from carbon sinks to carbon sources. No clear evidence was found for potential carbon sinks. Finally, I identified primer pairs from the database The Barcode of Life Data Systems (BOLD; https://boldsystems.org) that have previously been used to amplify genes from the species found at the studied locations. These primers can be used in future studies to track vegetation taxa in sediments, and thus better determine which species contribute organic matter and how this affects the role of sediments as a carbon sink or source.