Polar ecosystem: characteristics, fauna and flora

The polar ecosystem is, without a doubt, one of the most inhospitable that exist on this planet. Therefore, we are going to detail some of the main characteristics of the polar ecosystem :

Climatology

Temperatures rarely exceed 0ºC and are accompanied by winds of up to 100 km / h due to the large pressure differences.

Water cycle

Regarding the water cycle at the poles, it should be noted that there is a large amount of fresh water in a solid state, a characteristic to which all living beings that live there must adapt. The great masses of ice extend not only to the terrestrial surface, but also to the sea surface. Below 0ºC there are no liquid water courses. As for rainfall, it is usually scarce and occurs in the form of snow, which quickly turns into ice.

Albedo and ultraviolet radiation

Albedo is defined as the percentage of radiation reflected by the earth’s surface with respect to the total incident radiation. At the poles, the albedo is especially high. Ultraviolet radiation is also higher than on the rest of the planet.

Light cycles in the polar ecosystem

The differences between the hours of light and darkness per day, which can reach 24 hours of light and 24 hours of darkness, directly affect the scarce terrestrial and pelagic vegetation, as well as the fauna that inhabits these lands.

The polar ecosystem is found at the poles of planet Earth , both in the Arctic (North pole) and in the Antarctic (South pole) . The main difference between them is that the Arctic is made up of a thick layer of ice that floats on the ocean, while the Antarctic sits on the earth’s surface.

Also note that the polar ecosystem suffers seasonal cycles of expansion and withdrawal. Around it is the periglacial zone of tundra and permafrost, with which close ecological relationships are established.

The fauna presents specific adaptations to the polar climate. White coats and plumages that blend in with the ice cover are common. On the other hand, animals also tend to have a thick layer of fat under their skin that allows them to isolate themselves from the cold. Likewise, behavior patterns have been modified to overcome the colder months, such as hibernations and migrations .

Here we describe some of the best known species of the fauna of the polar ecosystem :

• Polar bear or white bear ( Ursus maritimus ): it is the only super-predator in the Arctic . Although its coat looks white, it is translucent, with hollow hair and dark skin that help it take better advantage of the heat. They feed especially on seals and other marine mammals. Here we explain everything about its status The polar bear is in danger of extinction .
• Arctic fox ( Vulpes lagopus ): it is a visiting predator that usually follows white bears, feeding on the carrion they leave behind.
• Penguins ( Spheniscidae ): There are several species of penguins in the Antarctic or South Pole polar ecosystem. These curious birds have lost the ability to fly and have adapted their limbs to life in the water, where they hunt fish and other animals. That is why they have a very aerodynamic body, with the legs acting as fins. Learn more about them with this other post in which we talk about Where penguins live and what they eat .

Discover much more about polar fauna with this other AgroCorrn article on What animals live in the North and South Pole .

The vegetation in the polar ecosystem is very low. In fact, vascular vegetation is only found in tundra areas , where herbaceous plants and shrubs abound , and even some riparian forests in valleys and places with less wind.

In general, very simple small plants proliferate, such as mosses, algae and lichens . All these plants have in common the absence of vascular structures, that is, of specialized body structures for the transport of raw or processed sap, many of them being bryophyte plants . In general, they take water from the environment by absorption, since it is usually not available in any other way.

In polar ecosystems we can discover a wide diversity of microscopic algae , such as diatoms . Since they have to adapt to very harsh conditions of temperature, light and salinity, with great changes throughout the year, they present very interesting adaptive strategies: some, for example, secrete a layer of “mucus” to protect the cell surface. of ice crystals. Those that live on the surface secrete special pigments to protect themselves from the high ultraviolet radiation that characterizes this medium, which can give the ice very striking tones.

Algae play a critical role in the primary production of the ecosystem. They convert carbon dioxide and inorganic matter into oxygen and organic matter, and are food for small invertebrates like krill. These, in turn, constitute the main food for fish of various species. As can be seen, algae mainly form the base of the food chain.

Vegetation and climate change

A recent study on the state and trends of vegetation in the Arctic in relation to climate change and global warming published in Ambio ^[1] , has shown that tundra vegetation is very resilient to temperature changes caused recently during the climate change, but not the rest of the plants that are included in this ecosystem.