Environmental Change in the Deep Ocean

Abstract

Patterns of abundance, biomass, and species richness are reviewed for deepsea ecosystems. Long-term monitoring studies have indicated that deep-sea ecosystems are sensitive to climatic variability through its influence on the quantity and quality of surface primary production. The potential impacts of climate change, through its effects on primary production and through changes in the temperature, pH, and oxygenation of the deep ocean are explored. It is concluded that deep-sea ecosystems are likely to be highly sensitive to changes in food supply and the physical environment driven by global climate change. As a result, ecosystem services will be negatively impacted with likely positive feedbacks to atmospheric CO 2 levels. It is a matter of urgency that baselines are established for diversity, abundance, and biomass of deep-sea ecosystems, particularly for the pelagic realm and that a mechanistic understanding is developed of how food supply and physical parameters affect community structure and function. 11.1

High Latitude Epipelagic and Mesopelagic Scattering Layers—A Reference for Future Arctic Ecosystem Change

“…Acoustic monitoring of the water column including the mesopelagic domain along with ground-truthed species composition data could be an effective method to examine how changes in the epipelagic zone affect the deep-water communities of the Arctic Ocean. Such initiatives are strongly recommended (Rogers, 2015). The magnitude of DSL acoustic backscattering and the determination of its biological components both to the west of the Spitsbergen archipelago and northwards into the Arctic Ocean should be evaluated on a regular basis as an important additional method to properly assess ecosystem change, although methodological caveats and challenges still exist (Handegard et al, 2013;Davison et al, 2015).…”

Investigating the environmental drivers of deep‐seafloor biodiversity: A case study of peracarid crustacean assemblages in the Northwest Atlantic Ocean

“…An implication of this result is that an increase in ocean temperature (particularly at continental slope depths [Balmaseda, Trenberth, & Kallen, 2013;Howes et al, 2015;Llovel, Willis, Landerer, & Fukumori, 2014;Ramirez-Llodra et al, 2011]) may result in depressed ecosystem functioning. For example, a reduction in the biomass of organic carbon-rich peracarids may suppress benthic carbon storage, this being of significance because of the importance of continental slopes for carbon storage globally (Levin & Dayton, 2009;Levin & Sibuet, 2012;Muller-Karger et al, 2005;Rogers, 2015;Sweetman et al, 2017).…”

“…Increasing deep‐sea temperatures will also increase faunal metabolic rates (Brown, Gillooly, Allen, Savage, & West, ; Hochachka & Somero, ; McClain et al, ; Seibel & Drazen, ). This, coupled with potentially reduced delivery of surface primary productivity to the seafloor, may negatively impact faunal biomass (Jones et al, ; Rogers, ; Sweetman et al, ). However, the potential impacts of rising temperature on deep‐sea benthos await investigation on a large scale (Sweetman et al, ; Yasuhara & Danovaro, ).…”

A Catalogue of Marine Biodiversity Indicators

“…The lack of indicators specifically addressing the bathyal and abyssal zone, and in particular the pelagic domain, can be regarded as an important gap in the current suite of indicators. These zones host characteristic communities and species, entangled within unique ecological processes that require specific sampling and assessment approaches (Costello et al, 2010;Danovaro et al, 2014;Thurber et al, 2014;Rogers, 2015) and, therefore, specific indicators for assessing their status. However, an understanding of deep-sea processes needs to be further developed along with baselines for several parameters, before sensitivity metrics can be incorporated into indicator approaches.…”