Marsh sediments chronically exposed to nitrogen enrichment contain degraded organic matter that is less vulnerable to decomposition via nitrate reduction.

Blue carbon habitats, including salt marshes, can sequester carbon at rates that are an order of magnitude greater than terrestrial forests. This ecosystem service may be under threat from nitrate (NO) enrichment, which can shift the microbial community and stimulate decomposition of organic matter. Despite efforts to mitigate nitrogen loading, salt marshes continue to experience chronic NO enrichment, however, the long-term consequence of this enrichment on carbon storage remains unclear.

Exploring epidermal mucus protease activity as an indicator of stress in Atlantic sturgeon (Acipenser oxyrinchus oxyrhinchus).

Atlantic sturgeon are anadromous fish that spend much of their life in near-shore environments. They are designated as "threatened" by the Committee on the Status of Endangered Wildlife in Canada and listed by the IUCN as "near threatened." In Canada, Atlantic sturgeon support small commercial fisheries in the Saint John River, New Brunswick, and the St.

Sulphide addition favours respiratory ammonification (DNRA) over complete denitrification and alters the active microbial community in salt marsh sediments.

The balance between nitrate respiration pathways, denitrification and dissimilatory nitrate (NO ) reduction to ammonium (DNRA), determines whether bioavailable nitrogen is removed as N gas or recycled as ammonium. Saltwater intrusion and organic matter enrichment may increase sulphate reduction leading to sulphide accumulation. We investigated the effects of sulphide on the partitioning of NO between complete denitrification and DNRA and the microbial communities in salt marsh sediments.

Nitrate addition stimulates microbial decomposition of organic matter in salt marsh sediments.

Salt marshes sequester carbon at rates more than an order of magnitude greater than their terrestrial counterparts, helping to mitigate climate change. As nitrogen loading to coastal waters continues, primarily in the form of nitrate, it is unclear what effect it will have on carbon storage capacity of these highly productive systems. This uncertainty is largely driven by the dual role nitrate can play in biological processes, where it can serve as a nutrient-stimulating primary production or a thermodynamically favorable electron acceptor fueling heterotrophic metabolism.

Bioreactivity and Microbiome of Biodeposits from Filter-Feeding Bivalves.

Bivalves serve an important ecosystem function in delivering organic matter from pelagic to benthic zones and are important in mediating eutrophication. However, the fate of this organic matter (i.e.

Variation in benthic metabolism and nitrogen cycling across clam aquaculture sites.

As bivalve aquaculture expands globally, an understanding of how it alters nitrogen is important to minimize impacts. This study investigated nitrogen cycling associated with clam aquaculture in the Sacca di Goro, Italy (Ruditapes philipinarum) and the Eastern Shore, USA (Mercenaria mercenaria). Ammonium and dissolved oxygen fluxes were positively correlated with clam biomass; R.