Biomass is the mass of living biological organisms in a given area or ecosystem at a given time. Biomass can refer to species biomass, which is the mass of one or more species, or to community biomass, which is the mass of all species in the community. It can include microorganisms, plants or animals. The mass can be expressed as the average mass per unit area, or as the total mass in the community.
Geomicrobiology is the scientific field at the intersection of geology and microbiology and is a major subfield of geobiology. It concerns the role of microbes on geological and geochemical processes and effects of minerals and metals to microbial growth, activity and survival. Such interactions occur in the geosphere, the atmosphere and the hydrosphere. Geomicrobiology studies microorganisms that are driving the Earth's biogeochemical cycles, mediating mineral precipitation and dissolution, and sorbing and concentrating metals. The applications include for example bioremediation, mining, climate change mitigation and public drinking water supplies.
A biogeochemical cycle, or more generally a cycle of matter, is the movement and transformation of chemical elements and compounds between living organisms, the atmosphere, and the Earth's crust. Major biogeochemical cycles include the carbon cycle, the nitrogen cycle and the water cycle. In each cycle, the chemical element or molecule is transformed and cycled by living organisms and through various geological forms and reservoirs, including the atmosphere, the soil and the oceans. It can be thought of as the pathway by which a chemical substance cycles the biotic compartment and the abiotic compartments of Earth. The biotic compartment is the biosphere and the abiotic compartments are the atmosphere, lithosphere and hydrosphere.
Microbial ecology is the ecology of microorganisms: their relationship with one another and with their environment. It concerns the three major domains of life—Eukaryota, Archaea, and Bacteria—as well as viruses.
Desulfobacterales are an order of sulfate-reducing bacteria within the phylum Thermodesulfobacteria. The order contains three families; Desulfobacteraceae, Desulfobulbaceae, and Nitrospinaceae. The bacterium in this order are strict anaerobic respirators, using sulfate or nitrate as the terminal electron acceptor instead of oxygen. Desulfobacterales can degrade ethanol, molecular hydrogen, organic acids, and small hydrocarbons. The bacterium of this order have a wide ecological range and play important environmental roles in symbiotic relationships and nutrient cycling.
Gammaproteobacteria is a class of bacteria in the phylum Pseudomonadota. It contains about 250 genera, which makes it the most genus-rich taxon of the Prokaryotes. Several medically, ecologically, and scientifically important groups of bacteria belong to this class. It is composed by all Gram-negative microbes and is the most phylogenetically and physiologically diverse class of Proteobacteria.
The Southern Pacific Gyre is part of the Earth's system of rotating ocean currents, bounded by the Equator to the north, Australia to the west, the Antarctic Circumpolar Current to the south, and South America to the east. The center of the South Pacific Gyre is the oceanic pole of inaccessibility, the site on Earth farthest from any continents and productive ocean regions and is regarded as Earth's largest oceanic desert. With an area of 37 million square kilometres it makes up ~10 % of the Earth's ocean surface. The gyre, as with Earth's other four gyres, contains an area with elevated concentrations of pelagic plastics, chemical sludge, and other debris known as the South Pacific garbage patch.
The Guaymas Basin is the largest marginal rift basin located in the Gulf of California. It made up of the northern and southern trough and is linked to the Guaymas Fault to the north and the Carmen Fault to the south. The mid-ocean ridge system is responsible for the creation of the Guaymas Basin and giving it many features such as hydrothermal circulation and hydrocarbon seeps. Hydrothermal circulation is a significant process in the Guaymas Basin because it recycles energy and nutrients which are instrumental in sustaining the basin's rich ecosystem. Additionally, hydrocarbons and other organic matter are needed to feed a variety of organisms, many of which have adapted to tolerate the basin's high temperatures.
Antje Boetius is a German marine biologist. She is a professor of geomicrobiology at the Max Planck Institute for Marine Microbiology, University of Bremen. Boetius received the Gottfried Wilhelm Leibniz Prize in March 2009 for her study of sea bed microorganisms that affect the global climate. She is also the director of Germany's polar research hub, the Alfred Wegener Institute.
The class Zetaproteobacteria is the sixth and most recently described class of the Pseudomonadota. Zetaproteobacteria can also refer to the group of organisms assigned to this class. The Zetaproteobacteria were originally represented by a single described species, Mariprofundus ferrooxydans, which is an iron-oxidizing neutrophilic chemolithoautotroph originally isolated from Kamaʻehuakanaloa Seamount in 1996 (post-eruption). Molecular cloning techniques focusing on the small subunit ribosomal RNA gene have also been used to identify a more diverse majority of the Zetaproteobacteria that have as yet been unculturable.
Hadesarchaea, formerly called the South-African Gold Mine Miscellaneous Euryarchaeal Group, are a class of thermophile microorganisms that have been found in deep mines, hot springs, marine sediments, and other subterranean environments.
Victoria J. Orphan is a geobiologist at the California Institute of Technology who studies the interactions between marine microorganisms and their environment. As of 2020, she is the Chair for the Center of Environmental Microbial Interactions.
Fumio Inagaki is a geomicrobiologist whose research focuses on the deep subseafloor biosphere. He is the deputy director of the Research and Development Center for Ocean Drilling Science and the Kochi Institute for Core Sample Research, both at the Japan Agency for Marine-Earth Science and Technology (JAMSTEC).
Wang Fengping is a Chinese marine microbiologist who studies microbes that live in deep sea and subsurface environments, with a special focus on the physiology and geochemical roles of organisms that cannot yet be cultivated in the lab. She is a professor at Shanghai Jiao Tong University.
Steven D’Hondt is an American geomicrobiologist who studies microbial communities living beneath the seafloor. He is a professor of oceanography at the University of Rhode Island.
Frederick (Rick) Colwell is a microbial ecologist specializing in subsurface microbiology and geomicrobiology. He is a professor of ocean ecology and biogeochemistry at Oregon State University, and an adjunct and affiliate faculty member at Idaho State University.
The hydrothermal vent microbial community includes all unicellular organisms that live and reproduce in a chemically distinct area around hydrothermal vents. These include organisms in the microbial mat, free floating cells, or bacteria in an endosymbiotic relationship with animals. Chemolithoautotrophic bacteria derive nutrients and energy from the geological activity at Hydrothermal vents to fix carbon into organic forms. Viruses are also a part of the hydrothermal vent microbial community and their influence on the microbial ecology in these ecosystems is a burgeoning field of research.
Holly Michael is an American hydrogeologist and Associate Professor of geology at the University of Delaware's College of Earth, Ocean, and Environment.
The deep biosphere is the part of the biosphere that resides below the first few meters of the surface. It extends down at least 5 kilometers below the continental surface and 10.5 kilometers below the sea surface, at temperatures that may reach beyond 120 °C (248 °F) which is comparable to the maximum temperature where a metabolically active organism has been found. It includes all three domains of life and the genetic diversity rivals that on the surface.
Danielle L. Dixson is an Associate Professor of Marine Ecology in the School of Marine Science and Policy at the University of Delaware. Her research focusses on how human-induced change to marine ecosystems impacts animal behaviour. Her work, now known to be fraudulent, was about understanding how ocean acidification affects the behaviour of coral reef fishes.
