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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The major composition of the ocean chemistry that is affected by atmospheric CO2 are understood for the most part and can be calculated accurately. However there is much uncertainty of the biological effects caused by ocean acidification and how it will vary amongst organisms; some may cope better than others. Even though the research on ocean acidification is still very young, there is already evidence of biological impacts due to changes in the chemistry of the ocean. The greatest evidence of the impactions of ocean acidification on marine ecosystems can be seen in experiments on calcifying organisms. When seawater is acidified to various amounts the formation and dissolution of calcium carbonate shells and skeletons in marine organisms such as reef-building corals, oysters and mussels, and phytoplankton and zooplankton which for the base for marine food webs (“Ocean Acidification: A National Strategy…”,
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Coral reefs are often thought of being “rainforests of the ocean” as they create a large diversity. A select type of coral control this diversity a symbiotic relationship with plankton. The distinct type of plankton are called zooxanthellae. This symbiotic relationship between hosts and partners that use photosynthesis, allow coral to skyrocket in seas where nutrients are poor and send calcium carbonate down to the bottom of the ocean in order to build reefs up in size (Toller et al. 2001).
As CO2 is absorbed into the ocean, it undergoes a chemical reaction that creates an unfavorable environment for many marine organisms. Carbon dioxide reacts with water (H2O) to form carbonic acid (H2CO3). Carbonic acid then rapidly dissolves to form hydrogen ions (H+) and bicarbonate ions (HCO3-). The ocean is naturally saturated with carbonate ions (CO3−2) whic...
Sharks are the apex predators of the ocean, meaning they regulate the marine food web. The ocean (there is only one, not 7) covers between 70 – 75% of the earth’s surface and houses 80 – 90% of all life on earth, yet sharks role in maintaining the ocean is often overlooked. The main reas...
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There are many people that don’t think of phytoplankton first when hearing the word ocean. Instead many would think about larger
...through the fish's guts. The revelation of this information could help other scientists have a better understanding of the potential threat these harmful bacteria pose and the role that this new ecosystem plays in the larger ocean ecosystem, including its potential to change the nutrients contained in the water.
Most of the stressors affecting coral reefs are anthropogenic, originating from human activity. Notably, stressors such as overfishing and nutrient pollution contribute by reducing the resilience of the reefs by increasing coral-algal competition and reducing coral recruitment, growth and survival (Zaneveld et. al, 2016). A field experiment conducted over the course of three years, simulated overfishing and nutrient pollution yielded an increase in turf and macroalgal cover while destabilizing microbiomes, elevating putative pathogen loads. Together, stressors and temperature combine to alter coral microbiomes by driving bacterial blooms. Yielding an increase in disease by more than twofold and increased mortality up to eight fold. (Zaneveld et. al,
Oceans are such so vast that people underestimate the impact their actions —seeming so insignificant— have on them. Humans have by and large taken the oceans for granted; not considering how important a healthy ocean is to our survival. A popular mind-set is that the oceans are a bottomless supply of fish, natural resources, and an infinite waste dump. There are myriad reasons why the oceans should be saved and the most obvious one is marine life. With 71% of the Earth being covered by water, it is obvious that sea creatures are predominant form of life, making up 80% of the species of life on Earth. However, as important as marine life is, that is not the only reason why saving the oceans is crucial. The ocean floor provides natural resources such as, oil, natural gas, petroleum, minerals, medications, and ingredients for foods and products. The economic benefits of the oceans are huge and significant, as well. Fishing and fish products have provided employment to 38 million people and have generated about $124 billion in economic benefits. However, oceans are on the verge of crisis, marine life, natural resources, transportation, the economy, and important ingredients are at risk due to overfishing, pollution, and acidification. Thus, in this essay I will argue that, oceans are not impervious to human activity and threatening the health of the ocean threatens the health of humanity, since oceans key to our survival.
Vannela, Raveender. "Are We “Digging Our Own Grave” Under the Oceans?" Environmental Science & Technology 46.15 (2012): 7932-933. Print.