{"id":7643,"date":"2025-11-13T10:45:56","date_gmt":"2025-11-13T09:45:56","guid":{"rendered":"https:\/\/www.polarpod.fr\/polar-encyclopedia\/oceanic-biodiversity-and-the-food-chain\/"},"modified":"2026-02-08T23:54:04","modified_gmt":"2026-02-08T22:54:04","slug":"oceanic-biodiversity-and-the-food-chain","status":"publish","type":"page","link":"https:\/\/www.polarpod.fr\/en\/polar-encyclopedia\/oceanic-biodiversity-and-the-food-chain\/","title":{"rendered":"OCEANIC BIODIVERSITY AND THE FOOD CHAIN"},"content":{"rendered":"[vc_row type=”full_width_background” full_screen_row_position=”middle” column_margin=”default” column_direction=”default” column_direction_tablet=”default” column_direction_phone=”default” bg_color=”#454156″ scene_position=”center” top_padding=”4%” bottom_padding=”0%” text_color=”light” text_align=”left” row_border_radius=”none” row_border_radius_applies=”bg” overflow=”visible” id=”intro” row_name=”Intro” color_overlay=”#0a0a0a” color_overlay_2=”#C02020″ overlay_strength=”0.5″ gradient_direction=”left_to_right” shape_divider_position=”bottom” bg_image_animation=”zoom-out-slow” gradient_type=”default” shape_type=””][vc_column column_padding=”no-extra-padding” column_padding_tablet=”inherit” column_padding_phone=”inherit” column_padding_position=”top” column_element_direction_desktop=”default” column_element_spacing=”default” centered_text=”true” desktop_text_alignment=”default” tablet_text_alignment=”default” phone_text_alignment=”default” background_color_opacity=”1″ background_hover_color_opacity=”1″ column_backdrop_filter=”none” column_shadow=”none” column_border_radius=”none” column_link_target=”_self” column_position=”default” gradient_direction=”left_to_right” overlay_strength=”0.3″ width=”1\/1″ tablet_width_inherit=”default” animation_type=”default” bg_image_animation=”none” border_type=”simple” column_border_width=”none” column_border_style=”solid” column_padding_type=”default” gradient_type=”default”][vc_row_inner column_margin=”default” column_direction=”default” column_direction_tablet=”default” column_direction_phone=”default” text_align=”left” row_position=”default” row_position_tablet=”inherit” row_position_phone=”inherit” overflow=”visible” pointer_events=”all”][vc_column_inner top_padding_desktop=”2%” bottom_padding_desktop=”0″ left_padding_desktop=”0″ right_padding_desktop=”0″ column_element_direction_desktop=”default” column_element_spacing=”default” desktop_text_alignment=”left” tablet_text_alignment=”default” phone_text_alignment=”default” background_color_opacity=”1″ background_hover_color_opacity=”1″ column_backdrop_filter=”none” column_shadow=”none” column_border_radius=”none” column_link_target=”_self” overflow=”visible” gradient_direction=”left_to_right” overlay_strength=”0.3″ width=”1\/1″ tablet_width_inherit=”default” animation_type=”default” enable_animation=”true” animation=”fade-in-from-bottom” animation_easing=”default” bg_image_animation=”none” border_type=”simple” column_border_width=”none” column_border_style=”solid” column_padding_type=”advanced” gradient_type=”default”][image_with_animation image_url=”4990″ image_size=”full” max_width=”150%” max_width_mobile=”default” animation_type=”entrance” animation=”None” animation_movement_type=”transform_y” hover_animation=”none” alignment=”center” border_radius=”none” box_shadow=”none” image_loading=”default”][\/vc_column_inner][\/vc_row_inner][\/vc_column][\/vc_row][vc_row type=”full_width_background” full_screen_row_position=”middle” column_margin=”5px” column_direction=”default” column_direction_tablet=”default” column_direction_phone=”default” bg_color=”#FFFFFF” scene_position=”center” top_padding=”1%” bottom_padding=”2%” left_padding_phone=”0″ constrain_group_6=”yes” right_padding_phone=”0″ text_color=”dark” text_align=”left” row_border_radius=”none” row_border_radius_applies=”bg” overflow=”visible” id=”actu” row_name=”Actualit\u00e9” advanced_gradient_angle=”0″ overlay_strength=”0.3″ gradient_direction=”left_to_right” shape_divider_position=”bottom” bg_image_animation=”none” gradient_type=”default” shape_type=””][vc_column column_padding=”no-extra-padding” column_padding_tablet=”inherit” column_padding_phone=”inherit” column_padding_position=”all” column_element_direction_desktop=”default” column_element_spacing=”0px” desktop_text_alignment=”default” tablet_text_alignment=”default” phone_text_alignment=”default” background_color_opacity=”1″ background_hover_color_opacity=”1″ column_backdrop_filter=”none” column_shadow=”none” column_border_radius=”none” column_link_target=”_self” column_position=”default” advanced_gradient_angle=”0″ gradient_direction=”left_to_right” overlay_strength=”0.3″ width=”1\/1″ tablet_width_inherit=”default” animation_type=”default” bg_image_animation=”none” border_type=”simple” column_border_width=”none” column_border_style=”solid” gradient_type=”default” column_padding_type=”default”][vc_column_text css=”” max_width=”700″ text_direction=”default”]\n

The Polar Encyclopedia<\/span><\/h1>\n[\/vc_column_text][\/vc_column][\/vc_row][vc_row type=”full_width_background” full_screen_row_position=”middle” column_margin=”30px” column_direction=”default” column_direction_tablet=”default” column_direction_phone=”default” bg_color=”#ffffff” scene_position=”center” top_padding=”4%” bottom_padding=”4%” text_color=”dark” text_align=”left” row_border_radius=”none” row_border_radius_applies=”bg” overflow=”visible” id=”ATMOSPHERE” row_name=”Seul sur la banquise” overlay_strength=”0.3″ gradient_direction=”left_to_right” shape_divider_position=”bottom” bg_image_animation=”none” gradient_type=”default” shape_type=””][vc_column column_padding=”no-extra-padding” column_padding_tablet=”inherit” column_padding_phone=”inherit” column_padding_position=”all” top_margin=”0%” column_element_direction_desktop=”default” column_element_spacing=”default” desktop_text_alignment=”default” tablet_text_alignment=”default” phone_text_alignment=”default” background_color_opacity=”1″ background_hover_color_opacity=”1″ column_backdrop_filter=”none” column_shadow=”none” column_border_radius=”none” column_link_target=”_self” column_position=”default” gradient_direction=”left_to_right” overlay_strength=”0.3″ width=”1\/4″ tablet_width_inherit=”default” animation_type=”default” bg_image_animation=”none” border_type=”simple” column_border_width=”none” column_border_style=”solid” column_padding_type=”default” gradient_type=”default”][nectar_global_section id=”8435″][\/vc_column][vc_column column_padding=”no-extra-padding” column_padding_tablet=”inherit” column_padding_phone=”inherit” column_padding_position=”all” column_element_direction_desktop=”default” column_element_spacing=”default” desktop_text_alignment=”default” tablet_text_alignment=”default” phone_text_alignment=”default” background_color_opacity=”1″ background_hover_color_opacity=”1″ column_backdrop_filter=”none” column_shadow=”none” column_border_radius=”none” column_link_target=”_self” column_position=”default” gradient_direction=”left_to_right” overlay_strength=”0.3″ width=”3\/4″ tablet_width_inherit=”default” animation_type=”default” bg_image_animation=”none” border_type=”simple” column_border_width=”none” column_border_style=”solid”][vc_row_inner equal_height=”yes” column_margin=”custom” column_margin_custom=”2px” column_direction=”default” column_direction_tablet=”default” column_direction_phone=”default” bottom_padding=”2%” text_align=”left” row_position=”default” row_position_tablet=”inherit” row_position_phone=”inherit” overflow=”visible” pointer_events=”all”][vc_column_inner column_padding=”no-extra-padding” column_padding_tablet=”inherit” column_padding_phone=”inherit” column_padding_position=”all” column_element_direction_desktop=”default” column_element_spacing=”default” desktop_text_alignment=”default” tablet_text_alignment=”default” phone_text_alignment=”default” background_color_opacity=”1″ background_hover_color_opacity=”1″ column_backdrop_filter=”none” column_shadow=”none” column_border_radius=”none” column_link_target=”_self” overflow=”visible” gradient_direction=”left_to_right” overlay_strength=”0.3″ width=”5\/6″ tablet_width_inherit=”default” animation_type=”default” bg_image_animation=”none” border_type=”simple” column_border_width=”none” column_border_style=”solid”][vc_column_text css=”” text_direction=”default”]\n

OCEANIC BIODIVERSITY AND THE FOOD CHAIN<\/span><\/h2>\n[\/vc_column_text][\/vc_column_inner][vc_column_inner column_padding=”no-extra-padding” column_padding_tablet=”inherit” column_padding_phone=”inherit” column_padding_position=”all” column_element_direction_desktop=”default” column_element_spacing=”default” desktop_text_alignment=”default” tablet_text_alignment=”default” phone_text_alignment=”default” background_color_opacity=”1″ background_hover_color_opacity=”1″ column_backdrop_filter=”none” column_shadow=”none” column_border_radius=”none” column_link_target=”_self” overflow=”visible” gradient_direction=”left_to_right” overlay_strength=”0.3″ width=”1\/6″ tablet_width_inherit=”default” animation_type=”default” bg_image_animation=”none” border_type=”simple” column_border_width=”none” column_border_style=”solid” column_padding_type=”default” gradient_type=”default”][nectar_icon icon_family=”linea” icon_style=”shadow-bg” icon_color_type=”color_scheme” icon_color=”Accent-Color” open_new_tab=”true” icon_padding=”5px” pointer_events=”all” url=”https:\/\/www.polarpod.fr\/wp-content\/uploads\/2025\/11\/BIODIVERSITY_FR.pdf” icon_size=”40″ icon_linea=”icon-basic-printer”][\/vc_column_inner][\/vc_row_inner][vc_row_inner equal_height=”yes” column_margin=”custom” column_margin_custom=”2px” column_direction=”default” column_direction_tablet=”default” column_direction_phone=”default” bottom_padding=”2%” text_align=”left” row_position=”default” row_position_tablet=”inherit” row_position_phone=”inherit” overflow=”visible” pointer_events=”all”][vc_column_inner column_padding=”no-extra-padding” column_padding_tablet=”inherit” column_padding_phone=”inherit” column_padding_position=”all” column_element_direction_desktop=”default” column_element_spacing=”default” desktop_text_alignment=”default” tablet_text_alignment=”default” phone_text_alignment=”default” background_color_opacity=”1″ background_hover_color_opacity=”1″ column_backdrop_filter=”none” column_shadow=”none” column_border_radius=”none” column_link_target=”_self” overflow=”visible” gradient_direction=”left_to_right” overlay_strength=”0.3″ width=”2\/3″ tablet_width_inherit=”default” animation_type=”default” bg_image_animation=”none” border_type=”simple” column_border_width=”none” column_border_style=”solid” column_padding_type=”default” gradient_type=”default”][vc_column_text css=”” text_direction=”default”]\n
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THE ARCTIC OCEAN AND ITS UNIQUE MARINE LIFE<\/span><\/h3>\n
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Compared to the other oceans on our planet, the Arctic Ocean is species-poor. Most marine life \u2013 from zooplankton to the creatures that inhabit the sea bed \u2013 is endemic, meaning that it is typical of the region. This Arctic fauna, which sometimes ventures into the Norwegian Sea but never far into the Bering Strait, is precious and must be protected. <\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n[\/vc_column_text][\/vc_column_inner][vc_column_inner column_padding=”no-extra-padding” column_padding_tablet=”inherit” column_padding_phone=”inherit” column_padding_position=”all” column_element_direction_desktop=”default” column_element_spacing=”default” desktop_text_alignment=”default” tablet_text_alignment=”default” phone_text_alignment=”default” background_color_opacity=”1″ background_hover_color_opacity=”1″ column_backdrop_filter=”none” column_shadow=”none” column_border_radius=”none” column_link_target=”_self” overflow=”visible” gradient_direction=”left_to_right” overlay_strength=”0.3″ width=”1\/3″ tablet_width_inherit=”default” animation_type=”default” bg_image_animation=”none” border_type=”simple” column_border_width=”none” column_border_style=”solid”][vc_column_text css=”” text_direction=”default”]\"\"[\/vc_column_text][\/vc_column_inner][\/vc_row_inner][vc_row_inner equal_height=”yes” column_margin=”custom” column_margin_custom=”2px” column_direction=”default” column_direction_tablet=”default” column_direction_phone=”default” bottom_padding=”2%” text_align=”left” row_position=”default” row_position_tablet=”inherit” row_position_phone=”inherit” overflow=”visible” pointer_events=”all”][vc_column_inner column_padding=”no-extra-padding” column_padding_tablet=”inherit” column_padding_phone=”inherit” column_padding_position=”all” column_element_direction_desktop=”default” column_element_spacing=”default” desktop_text_alignment=”default” tablet_text_alignment=”default” phone_text_alignment=”default” background_color_opacity=”1″ background_hover_color_opacity=”1″ column_backdrop_filter=”none” column_shadow=”none” column_border_radius=”none” column_link_target=”_self” overflow=”visible” gradient_direction=”left_to_right” overlay_strength=”0.3″ width=”1\/3″ tablet_width_inherit=”default” animation_type=”default” bg_image_animation=”none” border_type=”simple” column_border_width=”none” column_border_style=”solid” column_padding_type=”default” gradient_type=”default”][vc_column_text css=”” text_direction=”default”]\"\"[\/vc_column_text][\/vc_column_inner][vc_column_inner column_padding=”no-extra-padding” column_padding_tablet=”inherit” column_padding_phone=”inherit” column_padding_position=”all” column_element_direction_desktop=”default” column_element_spacing=”default” desktop_text_alignment=”default” tablet_text_alignment=”default” phone_text_alignment=”default” background_color_opacity=”1″ background_hover_color_opacity=”1″ column_backdrop_filter=”none” column_shadow=”none” column_border_radius=”none” column_link_target=”_self” overflow=”visible” gradient_direction=”left_to_right” overlay_strength=”0.3″ width=”2\/3″ tablet_width_inherit=”default” animation_type=”default” bg_image_animation=”none” border_type=”simple” column_border_width=”none” column_border_style=”solid”][vc_column_text css=”” text_direction=”default”]\n

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FROM ALGAE TO POLAR BEARS: THE ARCTIC FOOD CHAIN<\/span><\/h3>\n
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Even right next to the ice pack, algae (phytoplankton) grows and the creatures that comprise zooplankton (copepods, etc.) come to graze on it. The zooplankton attracts the small fish that feed on it and that are prey for sea birds, cetaceans and seals. These, in turn, are hunted \u2013 sometimes as far as the North Pole itself \u2013 by polar bears, which are followed by carrion eating birds who feed on the \u201cleft-overs\u201d. <\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n[\/vc_column_text][\/vc_column_inner][\/vc_row_inner][vc_row_inner equal_height=”yes” column_margin=”custom” column_margin_custom=”2px” column_direction=”default” column_direction_tablet=”default” column_direction_phone=”default” bottom_padding=”2%” text_align=”left” row_position=”default” row_position_tablet=”inherit” row_position_phone=”inherit” overflow=”visible” pointer_events=”all”][vc_column_inner column_padding=”no-extra-padding” column_padding_tablet=”inherit” column_padding_phone=”inherit” column_padding_position=”all” column_element_direction_desktop=”default” column_element_spacing=”default” desktop_text_alignment=”default” tablet_text_alignment=”default” phone_text_alignment=”default” background_color_opacity=”1″ background_hover_color_opacity=”1″ column_backdrop_filter=”none” column_shadow=”none” column_border_radius=”none” column_link_target=”_self” overflow=”visible” gradient_direction=”left_to_right” overlay_strength=”0.3″ width=”1\/1″ tablet_width_inherit=”default” animation_type=”default” bg_image_animation=”none” border_type=”simple” column_border_width=”none” column_border_style=”solid” column_padding_type=”default” gradient_type=”default”][vc_column_text css=”” text_direction=”default”]\n

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MARINE \u201cFERTILIZERS\u201d CARRIED ALONG BY THE CURRENTS <\/span><\/h3>\n
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Ocean currents favour the growth of the life forms at the lower end of the food chain by carrying along the elements that are so essential to the growth of planktonic algae. But in the Arctic, the key factor in the food chain is the seasonal extension of the ice pack, which affects the supply of nutrients and light. <\/p>\n

EVEN DURING THE LONG WINTER NIGHT, LIFE GOES ON<\/span><\/h3>\n

During the winter, plankton growth \u2013 which depends on photosynthesis \u2013 slows down very markedly, so larger marine life must find other sources of food, such as the organisms that have proliferated in summer, or various types of detritus. Some invertebrates even live by consuming reserves of body fat that they have built up during the summer. Other species that survive in winter include numerous bacteria as well as crustaceans, sponges and ice coral. <\/p>\n

PRIMARY PRODUCTION IN THE OCEANS<\/span><\/h3>\n

Oceanographers estimate the amount of vegetal plankton (biomass) present at any given moment in an oceanic region by measuring the chlorophyll content of the seawater. The amount of vegetal biomass in the ocean, almost totally made up of microscopic algae, is a thousand times less than terrestrial biomass. On the other hand, phytoplankton multiplies very rapidly: just one diatom, with two cellular divisions every 24 hours, can generate a million descendants over a period of 10 days. Just compare this to a tree in a forest, which can sometimes take 100 years to reach maturity\u2026 Because of the rate at which planktonic algae multiply, primary production in the world\u2019s oceans \u2013 calculated by measuring the carbon 14 absorbed by photosynthesis \u2013 can be similar to terrestrial biomass production: a hectare of ocean produces anything from 200 kg to nearly 2 metric tons of carbon each year, depending on the region, while a field of corn (maize) produces 2 metric tons of carbon per year. <\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n[\/vc_column_text][\/vc_column_inner][\/vc_row_inner][vc_row_inner equal_height=”yes” column_margin=”custom” column_margin_custom=”2px” column_direction=”default” column_direction_tablet=”default” column_direction_phone=”default” bottom_padding=”2%” text_align=”left” row_position=”default” row_position_tablet=”inherit” row_position_phone=”inherit” overflow=”visible” pointer_events=”all”][vc_column_inner column_padding=”no-extra-padding” column_padding_tablet=”inherit” column_padding_phone=”inherit” column_padding_position=”all” column_element_direction_desktop=”default” column_element_spacing=”default” desktop_text_alignment=”default” tablet_text_alignment=”default” phone_text_alignment=”default” background_color_opacity=”1″ background_hover_color_opacity=”1″ column_backdrop_filter=”none” column_shadow=”none” column_border_radius=”none” column_link_target=”_self” overflow=”visible” gradient_direction=”left_to_right” overlay_strength=”0.3″ width=”1\/1″ tablet_width_inherit=”default” animation_type=”default” bg_image_animation=”none” border_type=”simple” column_border_width=”none” column_border_style=”solid” column_padding_type=”default” gradient_type=”default”][vc_column_text css=”” text_direction=”default”]\n

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THE RICHEST ZONES OF THE ARCTIC OCEAN: COASTAL ZONES AND ESTUARIES<\/span><\/span><\/h3>\n
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During a month of May, scientists have observed 100 times more benthic amphipods under the surface of the coastal ice in northern Canada that on the seabed. In places where the sunlight penetrates as far as the seabed, production of plant matter \u2013 and therefore production of fauna as well \u2013 increases. When the thaw comes in spring, rivers wash down nutrients from inland areas, and ice melts more quickly in estuaries than elsewhere. So life persists just under the polar pack ice from one year to the next, despite the winter freeze-over \u2013 a fact that was long unknown to scientists.
\nGenerally speaking, the biomass accounted for by the species that are closest to the top of the food chain (the vertebrates) is relatively small. Unfortunately for these animals, pollutants move up the food chain to concentrate in the ultimate predators (seabirds, seals, cetaceans, polar bears, etc.). This is visible in the traces of heavy metals generated by industrial activity (zinc, cadmium, mercury, selenium, etc) in the teeth of seals and the fur of polar bears. <\/p>\n

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POLYNYAS \u2013 OASES OF LIFE AT THE SURFACE OF A FROZEN OCEAN<\/span><\/span><\/h3>\n

Even in the middle of the polar ice pack, the wind and the ocean currents cause the sea ice to break up, leaving areas of open water \u2013 i.e. free of ice \u2013 called polynyas. These are the site of abundant marine life activity (plankton, fish, sea-birds, marine mammals).
\nCertain polynyas appear regularly in the same place. An example here is the Great Siberian Polynya in the Laptev Sea, in the midst of ice that lasts from early October until the end of June. Even in mid-winter, it stretches 200 kilometres and its open water allows seals and walruses to breathe and therefore stay there \u2013 together with their predators like polar bears and foxes. And in early spring, eiders, guillemots and long-tail ducks arrive in thousands to feed on fish and shellfish there. <\/p>\n

A COMPLETE FOOD CHAIN WITHIN THE SEA ICE<\/span><\/span><\/h3>\n

Within the mass of sea ice itself, life forms subsist among the crystals of fresh-water ice and in the thin channels within seawater ice. A complete food chain can be found here, including planktonic algae (prasinophytes, dinoflagellates, chrysophytes, diatoms) and their decomposers (bacteria). Some of these organisms spend their whole life cycle inside the sea ice and others only part of their cycle, but all of them have adapted to a wide range of salinity and sunlight strength. This means that even during the Arctic winter, some algae can continue to photosynthesise using the very weak light of the polar night.
\nSome of these organisms originate in the sea and others are washed down to the sea by rivers. In winter, both their numbers and their species diversity are quite low, but as spoon as spring arrive numbers and diversity skyrocket, along with those of their predators. Then in autumn, when the sea starts to freeze over once more, they remain there, clinging to the ice. In sections of ice that have built up over several years, and thus several life cycles, the ice displays several strips or layers of microscopic communities that allow scientists to date successive spring \u201cflowerings\u201d. <\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n[\/vc_column_text][\/vc_column_inner][\/vc_row_inner][vc_row_inner equal_height=”yes” column_margin=”custom” column_margin_custom=”2px” column_direction=”default” column_direction_tablet=”default” column_direction_phone=”default” bottom_padding=”2%” text_align=”left” row_position=”default” row_position_tablet=”inherit” row_position_phone=”inherit” overflow=”visible” pointer_events=”all”][vc_column_inner column_padding=”no-extra-padding” column_padding_tablet=”inherit” column_padding_phone=”inherit” column_padding_position=”all” column_element_direction_desktop=”default” column_element_spacing=”default” desktop_text_alignment=”default” tablet_text_alignment=”default” phone_text_alignment=”default” background_color_opacity=”1″ background_hover_color_opacity=”1″ column_backdrop_filter=”none” column_shadow=”none” column_border_radius=”none” column_link_target=”_self” overflow=”visible” gradient_direction=”left_to_right” overlay_strength=”0.3″ width=”1\/1″ tablet_width_inherit=”default” animation_type=”default” bg_image_animation=”none” border_type=”simple” column_border_width=”none” column_border_style=”solid” column_padding_type=”default” gradient_type=”default”][vc_column_text css=”” text_direction=”default”]\n

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COMMUNITIES OF LIFE ON THE SEA BED<\/span><\/h3>\n
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Life in the depths of the Arctic Ocean, with its permanent \u201clid\u201d of sea ice, is not as rich as the life found in the world\u2019s other oceans because photosynthesis in its surface layers is weaker. However, just like on the seabed in other regions of the world, there are other oases of life that is not based on photosynthesis. These life forms are found near sea-bed vents emitting methane and hydrogen sulphate. In this case, the primary producers are not algae \u2013 because there is no light \u2013 but bacteria able to \u201cdigest\u201d methane or sulphates: photosynthesis has given way to chemosynthesis. In the Barents Sea, for example, oceanographers have discovered a mud volcano covered in a whitish film that, on examination, turned out to be bacteria\u2026 Researchers have now observed a new type of fauna whose whole food chain is based on methane-consuming bacteria. An oceanographic campaign in summer 2001 also discovered an active subsea ridge in the Arctic, the Gakkel Ridge, that includes a chain of subsea volcanoes and hydrothermal vents (or \u201cblack smokers\u201d). Samples of unknown species of sponges and crustaceans were brought back to the surface too. And there are undoubtedly more new oases of life down there just waiting to be discovered. <\/p>\n

BIOLOGIST\u2019S CORNER<\/span><\/h3>\n
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  • Low temperatures restrict the number of species (although those that are present display a very large number of individuals) and slow the metabolism of living beings. In warm oceans, certain copepods can accomplish their full life cycle in just 15 days, but in polar regions some copepods can take nearly two years to reach sexual maturity.<\/li>\n
  • Marine animals able to adapt to widely diverging salinity levels have an advantage in regions where life follows the freeze-melt cycle of the sea ice. For example, during the month of June, when ice is melting, salt water can become fresh water in less than an hour, later stabilising at 32% a few days later.<\/li>\n<\/ul>\n

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    PHYSICISTS’ CORNER<\/span><\/h3>\n

    Coastal polynyas<\/span> (from the Russian ‘polynia’, meaning ‘clearing’) form when the wind pushes sea ice offshore, thus bringing less cold underlying waters to the surface and creating an area of open water; in this ‘water hole’, the process of ice formation and wind expulsion is self-sustaining. Polynyas are true ‘factories’ of sea ice and thus of brines.
    \n“The climatic impact of polynyas is difficult to estimate. They are associated with the release of enormous quantities of heat into the atmosphere, but also with dense water plunges that transport gases exchanged with the atmosphere to the ocean floor.”
    \nIt is estimated that, through this permanent freezing, polynyas would yield several hundred watts per m2 to the atmosphere (latent heat of freezing).
    \nThey are distinguished from holoplankton<\/span>, which includes animals that remain planktonic their entire lives (foraminifera, radiolarians, copepods, chaetognaths, etc.).<\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n[\/vc_column_text][\/vc_column_inner][\/vc_row_inner][vc_row_inner equal_height=”yes” column_margin=”custom” column_margin_custom=”2px” column_direction=”default” column_direction_tablet=”default” column_direction_phone=”default” bottom_padding=”2%” text_align=”left” row_position=”default” row_position_tablet=”inherit” row_position_phone=”inherit” overflow=”visible” pointer_events=”all”][vc_column_inner column_padding=”no-extra-padding” column_padding_tablet=”inherit” column_padding_phone=”inherit” column_padding_position=”all” column_element_direction_desktop=”default” column_element_spacing=”default” desktop_text_alignment=”default” tablet_text_alignment=”default” phone_text_alignment=”default” background_color_opacity=”1″ background_hover_color_opacity=”1″ column_backdrop_filter=”none” column_shadow=”none” column_border_radius=”none” column_link_target=”_self” overflow=”visible” gradient_direction=”left_to_right” overlay_strength=”0.3″ width=”1\/1″ tablet_width_inherit=”default” animation_type=”default” bg_image_animation=”none” border_type=”simple” column_border_width=”none” column_border_style=”solid” column_padding_type=”default” gradient_type=”default”][vc_column_text css=”” text_direction=”default”]\n

    TO FIND OUT MORE \u2026<\/span><\/span><\/h3>\n

    BIBLIOGRAPHY<\/span><\/span><\/p>\n

      \n
    • L\u2019Arctique et l\u2019environnement bor\u00e9al, P. Av\u00e9rous \u2013 CNDP, 1995<\/li>\n
    • L\u2019Antarctique et l\u2019environnement polaire (2) \u201cEREBUS\u201d ,P. Av\u00e9rous \u2013 Dossier p\u00e9dagogique \u2013 CNDP-1992 <\/li>\n
    • Chercheurs sur l\u2019Oc\u00e9an\u201d, P.Av\u00e9rous \u2013 Hachette \u2013 1981<\/li>\n
    • Les missions de l\u2019Antarctica : la travers\u00e9e de Pacifique \u2013 1994<\/li>\n
    • Arctic Flora and Fauna : status and conservation (CAFF, Conservations of Arctic Flora and Fauna, Helsinski Edita, 2001)<\/li>\n
    • Le feu sous les glaces \u2013 Sylvie Rouat, Sciences et Avenir \u2013 f\u00e9vrier 2002<\/li>\n
    • L\u2019oc\u00e9an plan\u00e9taire, Science et Avenir \u2013 1994<\/li>\n<\/ul>\n[\/vc_column_text][\/vc_column_inner][\/vc_row_inner][\/vc_column][\/vc_row][vc_row type=”in_container” full_screen_row_position=”middle” column_margin=”default” column_direction=”default” column_direction_tablet=”default” column_direction_phone=”default” scene_position=”center” text_color=”dark” text_align=”left” row_border_radius=”none” row_border_radius_applies=”bg” overflow=”visible” overlay_strength=”0.3″ gradient_direction=”left_to_right” shape_divider_position=”bottom” bg_image_animation=”none”][vc_column column_padding=”no-extra-padding” column_padding_tablet=”inherit” column_padding_phone=”inherit” column_padding_position=”all” column_element_direction_desktop=”default” column_element_spacing=”default” desktop_text_alignment=”default” tablet_text_alignment=”default” phone_text_alignment=”default” background_color_opacity=”1″ background_hover_color_opacity=”1″ column_backdrop_filter=”none” column_shadow=”none” column_border_radius=”none” column_link_target=”_self” column_position=”default” gradient_direction=”left_to_right” overlay_strength=”0.3″ width=”1\/1″ tablet_width_inherit=”default” animation_type=”default” bg_image_animation=”none” border_type=”simple” column_border_width=”none” column_border_style=”solid”][nectar_global_section id=”6550″][\/vc_column][\/vc_row]\n","protected":false},"excerpt":{"rendered":"

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