Ecological Energetic Perspectives on Responses of Nitrogen-Transforming Chemolithoautotrophic Microbiota to Changes in the Marine Environment
"Transformation and mobilization of bioessential elements in the biosphere, lithosphere, atmosphere and hydrosphere constitute the Earth's biogeochemical cycles, which are driven mainly by microorganisms through their energy and material metabolic processes. Without microbial energy harvesting from sources of light and inorganic chemical bonds for autotrophic fixation of inorganic carbon, there would not be sustainable ecosystems in the vast ocean. Although ecological energetics (eco-energetics) has been emphasized as a core aspect of ecosystem analyses and microorganisms largely control the flow of matter and energy in marine ecosystems, marine microbial communities are rarely studied from the eco-energetic perspective. [...]"
Source: Frontiers in Microbiology
Authors: Hongyue Dang and Chen-Tung A. Chen
As CO2 Goes Up, Ocean Health Goes Down
"June 8th is World Oceans Day, a day to raise awareness of the ocean’s importance to the planet. 93 percent of the excess heat absorbed by the climate system goes into our oceans, creating major consequences. While more extreme storms and rising sea levels are some of the impacts of warmer oceans, rising CO2 levels and the resulting warmer oceans are impacting ocean health itself. The most wellknown effects are coral bleaching and ocean acidification, but an emerging issue is the decreasing oxygen levels in the warming waters. [...]"
Source: Climate Central
Reef-building corals thrive within hot-acidified and deoxygenated waters
"Coral reefs are deteriorating under climate change as oceans continue to warm and acidify and thermal anomalies grow in frequency and intensity. In vitro experiments are widely used to forecast reef-building coral health into the future, but often fail to account for the complex ecological and biogeochemical interactions that govern reefs. Consequently, observations from coral communities under naturally occurring extremes have become central for improved predictions of future reef form and function. Here, we present a semi-enclosed lagoon system in New Caledonia characterised by diel fluctuations of hot-deoxygenated water coupled with tidally driven persistently low pH, relative to neighbouring reefs. Coral communities within the lagoon system exhibited high richness (number of species = 20) and cover (24–35% across lagoon sites). [...]"
Source: Scientific Reports
Authors: Emma F. Camp
Deoxygenation of the Baltic Sea during the last century
"Deoxygenation is a global problem in coastal and open regions of the ocean, and has led to expanding areas of oxygen minimum zones and coastal hypoxia. The recent expansion of hypoxia in coastal ecosystems has been primarily attributed to global warming and enhanced nutrient input from land and atmosphere. The largest anthropogenically induced hypoxic area in the world is the Baltic Sea, where the relative importance of physical forcing versus eutrophication is still debated. We have analyzed water column oxygen and salinity profiles to reconstruct oxygen and stratification conditions over the last 115 y and compare the influence of both climate and anthropogenic forcing on hypoxia. [...]"
Source: Procedings of the National Academy of Sciences of the United States of America (PNAS)
Authors: Jacob Carstensen et al.
Widespread loss of ocean oxygen to become noticeable in 2030s
Deep sea life faces dark future due to warming and food shortage
New study reveals negative impact of climate change, human activity, acidification and deoxygenation on ocean and its creatures
Major impacts of climate change on deep-sea benthic ecosystems
"The deep sea encompasses the largest ecosystems on Earth. Although poorly known, deep seafloor ecosystems provide services that are vitally important to the entire ocean and biosphere. Rising atmospheric greenhouse gases are bringing about significant changes in the environmental properties of the ocean realm in terms of water column oxygenation, temperature, pH and food supply, with concomitant impacts on deep-sea ecosystems. [...]"
Fish under threat from ocean oxygen depletion, finds study
Oxygen levels in oceans have fallen 2% in 50 years due to climate change, affecting marine habitat and large fish such as tuna and sharks
Decline in global oceanic oxygen content during the past five decades
"Ocean models predict a decline in the dissolved oxygen inventory of the global ocean of one to seven per cent by the year 2100, caused by a combination of a warming-induced decline in oxygen solubility and reduced ventilation of the deep ocean. It is thought that such a decline in the oceanic oxygen content could affect ocean nutrient cycles and the marine habitat, with potentially detrimental consequences for fisheries and coastal economies. [...]"
Scientists have just detected a major change to the Earth’s oceans linked to a warming climate
"A large research synthesis, published in one of the world’s most influential scientific journals, has detected a decline in the amount of dissolved oxygen in oceans around the world — a long-predicted result of climate change that could have severe consequences for marine organisms if it continues."