The smallest and most involved players in this controversy are …
phytoplankton. |
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Their name comes from the Greek words φυτόν (phyton), meaning "plant", and πλαγκτός (planktos), meaning "wanderer" or "drifter" : so that we can see them as « the drifting plant", or "wandering water plants » in our paddles, ponds, lake or oceans....
Plankton is a familiar word to most people but phytoplankton refers to a slightly different thing.
Phytoplankton are « autotroph » in the plankton community, meaning self-feeding living being or « producer ». They are able make their own food, complex organic compounds such as carbohydrates, fats, and proteins, from simple substances present in its surroundings, generally using energy from light (photosynthesis).
Therefore, phytoplankton are the bottom of the whole marine food chain. They are the micro-organisms eaten by whales, shrimps, snails, seastars and so on. Most phytoplankton are too small to be seen with the unaided eye, but their presence can become conspicuous though.
When present in high enough numbers, they may appear as a green discoloration of the water due to the presence of chlorophyll within their cells (although the actual color may vary with the species of phytoplankton present : blue as well as so called red tide can appear on the surface). When it happens over large patches of ocean water, this rapid increase or accumulation in the population of one or a small number of phytoplankton species is what is called ocean phytoplankton bloom, or, more generally, algae bloom.
Plankton is a familiar word to most people but phytoplankton refers to a slightly different thing.
Phytoplankton are « autotroph » in the plankton community, meaning self-feeding living being or « producer ». They are able make their own food, complex organic compounds such as carbohydrates, fats, and proteins, from simple substances present in its surroundings, generally using energy from light (photosynthesis).
Therefore, phytoplankton are the bottom of the whole marine food chain. They are the micro-organisms eaten by whales, shrimps, snails, seastars and so on. Most phytoplankton are too small to be seen with the unaided eye, but their presence can become conspicuous though.
When present in high enough numbers, they may appear as a green discoloration of the water due to the presence of chlorophyll within their cells (although the actual color may vary with the species of phytoplankton present : blue as well as so called red tide can appear on the surface). When it happens over large patches of ocean water, this rapid increase or accumulation in the population of one or a small number of phytoplankton species is what is called ocean phytoplankton bloom, or, more generally, algae bloom.
Algae blooms are natural occurrences triggered by increased water temperature and sunlight, that's to say when the perfect conditions for the tiny plants to grow are gathered.
As any other plant, phytoplankton consume carbon during photosynthesis, and the carbon is incorporated in the phytoplankton (just as carbon is stored in the wood and leaves of a tree). Unlike any other plant though, they have a very brief span of life; indeed, while a bloom may last several weeks, the life span of any individual phytoplankton is rarely more than a few days.
Born in a day, phytoplankton are already dying on the next. Some of the carbon they capture is carried to the deep ocean as their dead body falls straight down to the bottom of the ocean's sediment layers, and some is transferred to different layers of the ocean as phytoplankton are eaten by other creatures, which themselves reproduce, generate waste, and die. Through this mechanism, phytoplankton are responsible for most of the transfer of carbon dioxyde from the atmosphere to the ocean, as one step of the marine "carbon cycle".
As any other plant, phytoplankton consume carbon during photosynthesis, and the carbon is incorporated in the phytoplankton (just as carbon is stored in the wood and leaves of a tree). Unlike any other plant though, they have a very brief span of life; indeed, while a bloom may last several weeks, the life span of any individual phytoplankton is rarely more than a few days.
Born in a day, phytoplankton are already dying on the next. Some of the carbon they capture is carried to the deep ocean as their dead body falls straight down to the bottom of the ocean's sediment layers, and some is transferred to different layers of the ocean as phytoplankton are eaten by other creatures, which themselves reproduce, generate waste, and die. Through this mechanism, phytoplankton are responsible for most of the transfer of carbon dioxyde from the atmosphere to the ocean, as one step of the marine "carbon cycle".
Second and most important element, their presence in high number on the surface of the ocean makes their contribution to carbon sequestration massive. Through photosynthesis, phytoplankton consume carbon dioxide on a scale equivalent to forests and other land plants. Worldwide, this “biological carbon pump” transfers about 10 gigatonnes of carbon from the atmosphere to the deep ocean each year.
Even small changes in the growth of phytoplankton may affect atmospheric carbon dioxide concentrations.
The core element for this potential climate control project is iron. Other factors than light and water temperature play a role in phytoplankton's reproduction, among which, the presence of nutrients such as nitrate or phosphate and also the presence of certain amounts of iron. Iron is often identified as the limiting nutrient for phytoplankton bloom in some desolated waters where iron concentrations are particularly low. Why do phytoplanktons need iron? All living things need macronutrients and micronutrients in order to survive. Iron is a micronutrient (think of it as a vitamin supplement) and a trace element necessary for photosynthesis in all plants.
Ocean Iron Fertilization, then, is this idea that made its way from some scientists' mind up to the United Nation's panels for climate discussion, that these small "ocean producers" could be made to contribute to the reduction of green house effect concentration, directly linking phytoplankton to climate change mitigation.
The core element for this potential climate control project is iron. Other factors than light and water temperature play a role in phytoplankton's reproduction, among which, the presence of nutrients such as nitrate or phosphate and also the presence of certain amounts of iron. Iron is often identified as the limiting nutrient for phytoplankton bloom in some desolated waters where iron concentrations are particularly low. Why do phytoplanktons need iron? All living things need macronutrients and micronutrients in order to survive. Iron is a micronutrient (think of it as a vitamin supplement) and a trace element necessary for photosynthesis in all plants.
Ocean Iron Fertilization, then, is this idea that made its way from some scientists' mind up to the United Nation's panels for climate discussion, that these small "ocean producers" could be made to contribute to the reduction of green house effect concentration, directly linking phytoplankton to climate change mitigation.