Terrestrial primary production is acknowledged as a major contributor to atmospheric carbon transformation and storage. In contrast, marine primary production, especially the contribution from kelp forests, remains less studied and accounted for. To facilitate studies on marine kelp and organic carbon, we here introduce an environmental DNA-based approach for tracing two common kelp species in Nordic marine sediments, establis...

Indicators can be powerful tools to measure progress towards achieving societal goals, and many indicators have been developed for sustainability goals nationally and internationally. When indicators are developed solely through top-down approaches without engaging local knowledge, they often fall short of capturing local perceptions and concerns relevant to decision-making. The aim of this project was to co-create a Coastal B...

Lakes worldwide are affected by multiple stressors, including climate change. This includes massive loading of both nutrients and humic substances to lakes during extreme weather events, which also may disrupt thermal stratification. Since multi‐stressor effects vary widely in space and time, their combined ecological impacts remain difficult to predict. Therefore, we combined two consecutive large enclosure experiments with a...

A growing need for food is causing increased interest for seaweed farming globally. This requires the knowledge of the industry’s effects on the marine environment. We therefore aimed to explore the communities hosted by a kelp farm compared to that of wild kelp forests. The study was performed in mid-western Norway. Kelp associated fauna were collected from farmed kelp ( Saccharina latissima and Alaria esculenta ), in wild ke...

Aim Macroalgal habitats are believed to be the most extensive and productive of all coastal vegetated ecosystems. In stark contrast to the growing attention on their contribution to carbon export and sequestration, understanding of their global extent and production is limited and these have remained poorly assessed for decades. Here we report a first data‐driven assessment of the global extent and production of macroalgal hab...

Kelp forests are productive coastal ecosystems that provide a range of ecosystem services. Mapping the distribution and area occupied by kelp forests is a critical step to identify their ecosystem functions and services, including their role in the carbon cycle, and to detect changes in their distribution. We compiled quantitative data of the dominant genera Laminaria and Saccharina across the Nordic region, allowing us to sep...

Vegetated coastal and marine habitats in the Nordic region include salt marshes, eelgrass meadows and, in particular, brown macroalgae (kelp forests and rockweed beds). Such habitats contribute to storage of organic carbon (Blue Carbon – BC) and support coastal protection, biodiversity and water quality. Protection and restoration of these habitats therefore have the potential to deliver climate change mitigation and co-benefi...

There is an increasing focus on ecosystem services provided by macroalgae worldwide, many which depend on its structural and morphological characteristics. Here we investigated how characteristics of canopy kelp plants of Laminaria hyperborea varies along the Norwegian part of the NE Atlantic. Ten characteristics related to size, allometry, density, biomass and epiphytes were analyzed along wide gradients of depth, wave exposu...