Дата публикации: 02 ноября 2021
Автор(ы): Pyotr KOLOSOV →
Публикатор: Научная библиотека Порталус
Рубрика: ЭКОЛОГИЯ →
Источник: (c) Science in Russia, №2, 2013, C.107-112 →
Номер публикации: №1635844740
Pyotr KOLOSOV, (c)
by Pyotr KOLOSOV, Dr. Sc. (Geol. & Min.), chief research assistant of the RAS SB Institute of Geology of Diamonds and Rare Metals (Yakutsk), expert of the International Union of Geosciences for Assessment of Objects-nominees to the UNESCO World Heritage List
Upon the decision of the 36th session of the UNESCO World Heritage Committee held in July 2012 in St. Petersburg, the Russian National Natural Park LENA COLUMNS has been entered on the World Heritage List. This means that the reputable international organization has acknowledged the fact that in the middle reaches of the Lena, major river of the North-Eastern Siberia, there is an object of high value for the whole of mankind.
STATUES NOT MADE BY HANDS
Let us define more precisely: the park is located along the banks of the great river (it is 4,400 km long, i.e. it ranks 10th in length and 8th in depth) in the area of estuaries of its right tributary Buotama and its left tributary Sinyaya; the area of the park is 442,788 ha. It includes a natural monument of an extraordinary beauty-famous rocks Lena Columns, Oimuransky fragment of the West-Yakutsk Barrier Reef is one of the oldest in the world. Rich residues of former fauna and flora have been discovered in the classical Early Cambrian (542-488 mln years ago) sediments there.
The park in Yakutia, which is on the UNESCO World Heritage List* has a unique value from a scientific point of view. Lena columns are an outstanding example of formation and preservation of a significant landscape in special climatic conditions typical of the north-east of Russia. Besides, they are of a huge aesthetic value.
The columns are located 40 km along the bank and are formed by carbonaceous rocks of the Early Cambrian.
*As of 2012, there are 962 objects in the UNESCO World Heritage List (774 objects of culture and 188 natural objects), 26 of them are located in the territory of Russia (15 cultural and 11 natural objects).-Ed.
Map of Yakutia. Location of Lena and Sinsk Pillars.
The rocks (up to 100 m high) have a unique appearance, can be easily observed from the river and perfectly harmonize with the neighboring landscape. Shape of the rocks is very unusual: they look like fantastic sculptures modeled by nature.
Formation of such an amazing stone landscape (formed presumably 400,000 years ago, i.e. quite recently in terms of geological history) is associated with "frost-shattered" weathering under the conditions of rather significant daily fluctuations of the temperature of atmospheric air up to 40 °C, which is usual for a region with a severe continental climate in the zone of permafrost.
Undoubtedly, Lena columns attracted people who sailed past them starting from ancient times. It is quite possible that they impressed not only ancestors of local aboriginal peoples, but also first emigrants to the North America: they often crossed the Lena and went through the territory of the present Yakutia, then by the earthen bridge of Bering in ancient times connecting Asia and America. Our contemporaries are impressed by the natural beauty of the rocks too.
Two bin years ago at latest, in the Pre-Cambrian*, ecosystems on the sea bottom in many regions of the world were formed with the active participation of solely cyanobacteria and bacteria or sometimes algae. This is
* According to the scale of geological epochs, the Pre-Cambrian ended 542 mln years ago.-Ed.
evidenced by Pre-Cambrian stromatolithic structures (organogenic sedimentation structures formed as a result of life activity of cyanobacteria and alga communities) described by some researchers as reefs. In fact, there are no skeleton organisms in these formations that could form a frame of these structures and thus they cannot be taken as reefs (even though in the Pre-Cambrian there began forming new ties between living organisms, i.e. mutually beneficial functions supporting the ecosystem and existence of the community as an organic unity). Skeleton organisms appeared later, in the Cambrian.
In the Pre-Cambrian, the Siberian Platform (and, consequently, the territory of the park Lena Columns) was located near paleoequator. It was there, on this enormous separate continent-them its major part was covered by shallow waters-where a completely new ecosystem (a mutually beneficial symbiosis of aquatic plants and animals), so called reef ecosystem originated. According to the famous American geologist Francis Pettijohn, it was "an island of active life", where further developed different groups of organisms, and rather perfect adaptive morphological structures were formed. Development of this ecosystem in the Early Cambrian is associated with the appearance on the Earth of animals with a calcareous skeleton and calcareous bushy algae. As for the most ancient reef-forming skeleton organisms, they are archaeocyathae*. These benthic animals,
*Archaeocyatha-a cubiform benthic animal (living in bottoms of water bodies).-Ed.
resembling sponges, originated in the eastern part of the Siberian platform (present-day western Yakutia) 535 mln years ago. As for other regions of the world, these animals originated there about 530 mln years ago, in other words, they are much younger. Hence the conclusion: all archaeocyatha-alga reefs and bioherms* found in different parts of the planet (they are especially numerous in Australia) were formed later than Oimuransky Reef, which is a part of the West-Yakutia Barrier Reef, discovered by the national geologist Ana-toly Bobrov in 1941.
At present, coral reefs are most studied reef structures (first coral reefs formed on our planet long ago, in the Silurian, 440-400 mln years ago). The size of some of them, for example, the Big Barrier Reef near the Australian coast, is really striking: it is 2,300 km long and from 2 to 150 km wide. It is the biggest structure created on the Earth by living organisms. About 14 thous. species inhabit reef waters these days. There animals and algae live in a mutually beneficial symbiosis. According to the data obtained by Dmitry Fashchuk, Dr. Sc. (Geogr.), (RAS Institute of Geography), the latter use a specific set of biochemical processes to make the coral produce limestone more actively and form the skeleton of the reef structure.
Speaking of the West-Yakutia Barrier Reef with Oimuransky Reef as its part, represented in the natural reserve Lena Columns, it is necessary to point out that it is the only place on the planet where we can see the most ancient documentary evidence of mutually beneficial relations between symbionts-animals with a calcareous skeleton and calcareous algae (it is they who form a firm reef frame). In the geological periods following the Early Cambrian, the reef ecosystem kept developing; it turned out to be very comfortable for evolution of organisms of different types. Their petrified remains preserved till now tell us about the environment, many representatives of wildlife lived in and replaced each other for 500 mln years.
It is worth saying that the West-Yakutia Barrier Reef (it was 2,000 km long) had a great effect on the origin of specific conditions of the environment and on the development of life in them in the Cambrian, comparable with the origin of land ecosystems, inhabited by first land plants and animals, later on.
The Oimuransky Reef has a significant scientific, research and educational value and is an accessible and
* Bioherms-calcareous bumps in the bottom of a water body, formed by attached organisms (algae, archaeocyathae, corals, sponges, Bryo-zoa, etc.), depositing lime and preserving a fixed position after fading off.-Ed.
very interesting museum of fossil nature in the open air. It is a place where we can clearly see an early biological diversity on our planet: innumerable petrified remains of tens of species of cubiform benthic animals (archaeocyathae) and lower aquatic plants (calcareous bushy algae of the Epiphyton genus). It is a place where you can see premier representatives of the calcareous flora and fauna close to tropical. And this is a region, where today predominates permafrost and a severe continental, rather cold, climate.
CAMBRIAN "BURST" IN YAKUTIA
If you assess fossil samples available in the natural park Lena Columns in terms of the scale of processes that ever happened on the Earth, they will turn out to be an outstanding example of explosive evolution of marine organisms in the beginning of Early Cambrian mass appearance and predominance of calcareous algae in the plant kingdom and of invertebrates having a firm skeleton and shell in the animal kingdom. This crucial event in the development of the organic world is clearly imprinted in the layers of carbonate deposits that accumulated for more than 20 mln years (535-513 mln years
ago) and are now open for visual studies or, as scientists say, are "well denuded".
Generic and specific diversity of fossil animals discovered in the territory of the park is really enormous: archaeocyathae (40 families and 111 species), trilobites* (78 families and 122 species), hyolithae (55 families and 88 species), brachiopods (14 families and 14 species), molluscs (10 families and 14 species), sponges (1 genus and 1 species), khiolitotelminty** (3 families and 9 species), tubulous problematics*** (7 families and 10 species), tommotiidy**** (1 genus and 1 species) and other zooproblematics (7 families and 13 species)-all in all 215 families and 382 species of marine animals of the
*Trilobites-extinct class of sea anthropods.-Ed.
** Khiolitozoa, brachiopods, khiolitotelminty-extinct marine invertebrates.-Ed.
*** Problematics-organisms of yet unknown taxonomic group.-Ed.
Early Cambrian. Many of them were singled out on the basis of materials collected in the Lena Columns for the first time.
Paleontologists know that before the above-mentioned animals in the Pre-Cambrian, living organisms had been basically represented by microorganisms (bacteria, cyanobacteria and noncalcareous algae) for 3 bin years and then, before the beginning of Cambrian, by skeletonless mollusks (medusoids, dickinsoni-idy*, presumably flat worms and other "problematic" organisms). With the appearance of a skeleton and a shell, many animals got an opportunity for further development and distribution throughout the world. It is not by chance that many scientists from different countries emphasized a significant importance of the Early Cambrian. "We still cannot understand this abrupt change
* Dickinsoniidy-leaf-shaped bilaterally-symmetrical segmental organisms.-Ed.
in the character of life"-this is how it was characterized by the founder of a number of geosciences Acad. Vladimir Vernadsky. According to the biochemist Prof. Heinz Low-enstam from the California Institute of Technology (USA), it was "a culmination of a long evolution". The national paleontologist Acad. Alexei Rozanov speaks of the appearance of "almost all types of animals within two centuries of the Early Cambrian".
The author of this article took notice of the mass appearance of calcareous algae (mainly above-mentioned bushy algae), that took place for the first time on the Earth, in the Early Cambrian. They inhabited bottoms of water bodies, increased free oxygen content, and thus, along with other circumstances, created conditions for development of a calcium skeleton in many sea animals.
In a word, it was a brand new phase in the development of animals, a beginning of a new quality, new opportunities realized in subsequent geological periods. Paleonto-logical and paleoalgological (algal) residues found in the natural park Lena Columns are a bright example of the said phase.
In February 1995, on the initiative of the author of this article, the International Union of Geological Sciences (its headquarters was located in Norway that time) entered the geological outcrop-the natural monument Lena Columns-on the world List of Geological Locations. In July 2012, the whole park was recognized the world heritage as an outstanding example of reflection of the main historical epochs of the Earth, including traces of ancient life and significant geological processes, which are still going on in the development of forms of terrestrial surface, significant geomorphological or physical and geographical peculiarities of the relief. To confirm this new status, in November of the same year President of the Republic of Sakha Yegor Borisov was awarded the UNESCO certificate.
It is worth mentioning that long-term fruitful scientific efforts of some generations of geologists and paleontologists from Moscow, St. Petersburg, Novosibirsk and Yakutsk, made a lot for public recognition of a natural treasure on the Lena. These works commenced in 1850, when the geologist Nikolai Meglitsky discovered primitive multicellular animals (archaeocyathae), one of the earliest skeletal sea benthic sponge-like organisms, near the settlement of Sinskforthe first time in the world. Further research works carried out by paleontologists Acad. Alexei Rozanov, Drs. Sc. (Geol. & Miner.) Inessa Zhuravleva, Lada Repina, etc., showed: skeletal sea animals (archaeocyathae, trilobites, brachiopods, etc.) spread throughout the world from the region of Lena Columns. This important scientific result was proved by experts from over 30 countries, who participated in 4 International Excursions (1973, 1981, 1990 and 2008) in the region under consideration arranged by the RAS SB Institute of Geology of Diamonds and Rare Metals with the participation of RAS Institutes of Paleontology, Geology, etc., and under auspices of the administration of the Republic of Sakha.
The value of the natural park Lena Columns is so great that the whole world will support its further preservation along with such famous natural monuments as the Big Barrier Reef near the Australian coast, Grand Canyon National Park in the USA, Škocjan Caves in Slovenia, Galapagos Islands in Ecuador, Lake Baikal in Russia and other treasures of mankind.
Recognition of the park as a part of the world heritage will promote further dissemination of information on the crucial phase of development of animals in the history of life on the Earth, beginning of biological diversity with the participation of skeletal animals, as well as preservation of nature, education of the youth and development of tourism in the Republic of Sakha (Yakutia), the biggest region of Russia.
Опубликовано на Порталусе 02 ноября 2021 года
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