The concept of the microbial loop first began in 1926 by Vernadskii, who studied heterotrophic and phototrophic microbial metabolism; and understood that these systems represented a major part of total metabolism in the oceans (Pomeroy, 1988). Older techniques that scientists used for enumerating marine bacteria were by plate counts, serial dilutions and phase-contrast microscopy. These numbers represented about 10% of actual numbers and are no longer used (Azam et al, 1983). Scientists were unable to completely understand the microbial loop until recently when ultrafiltration techniques, applied electronic microscope techniques; and genomic techniques were developed to quantify biomass in oceans to study the bacteria and microorganisms that are important in oceanic processes. It was by these techniques, that a study in 1983 by Azam et al, discovered the trend that with an increase in bacterial numbers and biomass there is an increase in primary productivity. This was one of the key findings that led scientists to understand the microbial loop.
The microbial loop is the most critical process in the marine food web, because it increases the efficiency of the system by making dissolved organic matter available to other organisms in the food web. It provides the matter and energy for the rest of the system and keeps the energy flowing. These in turn have implications on very important resources such as productivity of fisheries or how much carbon is able to reach the ocean floor. In this paper, research was done to see why and how the microbial loop is such an important process in the oceans. Also discussed in this paper, are what the loop consists of, how it operates, the matter and energy that cycles through the loop, as well...
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According to NOAA phytoplankton are microscopic organisms that continuously convert sunlight and nutrients into living tissue. Phytoplankton can be harmful to the bay because they at an uncontrollable rate causing harmful algae blooms when there is an abundance of nutrients. Phytoplankton also serve as the main food source for a larger but still microscopic organism named Zooplankton. Marine Bio.org did a study on zooplnkton revealing that they are very weak swimmers making them an easy food source for any larger organsim. Zooplanktons’ main purpose serves as the main food source for small fish and
Rachel Carson worked at the US Fish and Wildlife Service (FWS) as a marine biologist. While at the FWS, Carson produced three books on the ocean’s ecosy...
Garrison, Tom. "Chapter 12: Coasts." Oceanography: An Invitation to Marine Science. 7th ed. Cengage Learning, 2010. 319+. Print.
In absence of calcium carbonate, coral and shellfish can’t survive. The ecosystem of ocean depends on these organisms because they offer a large source of food at the bottom of the food chain. They need to be abundant in order t...
Princeton University Press. “The Extreme Life of the Sea.” princeton.edu. Princeton University Press. 11 Feb. 2014 Web. 12 Feb. 2014.
Coral reefs are the most biodiverse ecosystem on the planet. There are more than 25,000 known species of organisms and countless others that have yet to be identified (Helvarg, 2000). Reefs thrive on the shallow edge of tropical seas, most often on the eastern edge of continents along warm water currents that brush the coasts. Reefs cannot live in cold waters and are limited by ocean depth and available sunlight. Coral is the foundation of the reef community, providing a three-dimensional structure where thousands of species of vertebrates and invertebrates live and feed. Some species of coral are hard, while others soft. Some are branched, yet others are compact and rounded. Coral is made up of large communities of tiny jellyfish like polyps. These polyps absorb calcium from the sea water and secrete a hard limestone skeleton. At night the polyps extend sticky, stinging tentacles from their skeletons to capture and consume small floating organisms such as zooplankton. Every coral has a two-stage life cycle: the larva, and the polyp. The larval stage is free swimming, and the polyp is stationary. Ocean currents carry the larva from the stationary parent polyp to any hard, clean, silt-free surface where, if the conditions are perfect, the larva grows into a coral forming polyp, never to move again (Levin, 1999). One of the most valuable resources for coral polyps are algae. Some live on the coral skeletons, but one type in particular, zooxanthellae, lives inside the tissue of the polyps. Zooxanthellae makes up about half the weight of the fleshy polyps and are not only a valuable food resource, but they are responsible for the brilliant colors associated with coral. When coral looses these prec...
Experience plays an immense role in presenting the desolation that age and education has on one's capacity to remember. Individuals compare and contrast the correlation between these two variables; for example, the greater ones age the less recollection they seem to have. However, Psychologists Agneta Herlitz and Jenny Rehnman challenged this case by presenting a similar a preposition comparing two opposite variables: Does one’s sex affect his or her ability to remember day to day events? The interconnection between sex and memory is surprisingly a controversial topic. According to the research they provide, an individual’s sex does, indeed, play an immense role in commemorating the affairs that arise day to day.
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Ellycia R Harrould-Kolieb and Dorothée Herr co-wrote the article Ocean Acidification and Climate Change: Synergies and Challenges of Addressing both under the UNFCCC which was published in the 2012 Journal of Climate Policy. The article describes how the release of climate-change-causing carbon dioxide into our atmosphere is causing ocean acidification but through international policies the effects of ocean acidification can be mitigated.
Lotze, Heike K., Marta Coll, Anna M. Magera, Christine Ward-Paige, and Laura Airoldi. "Recovery of Marine Animal Populations and Ecosystems." Trends in Ecology & Evolution 26.11 (2011): 595-605. Print.
As a mariner its important to know about the marine life, that was one reason I have chosen this topic for my today’s short presentation.