Сборник материалов международной научной конференции студентов, магистрантов, аспирантов



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О.О. Дорожко, А.Н. Маевская


Республика Беларусь, Брест, БрГУ имени А.С. Пушкина

Научный руководитель – Н.В. Иванюк


OCEANS: ORIGIN, AGE, EVOLUTION

Seventy percent of the Earth’s surface is covered with water. Where did it come from? How did it make its way from the deep Earth to the surface of the planet? And most importantly, why has liquid water persisted on the Earth when it doesn’t appear to have done so elsewhere in the solar system? The full story takes us back to the formation of our “water planet”.

Everything in our solar system – the Sun and the planets – formed about 4.55 billion years ago from a rotating disk of gas, dust, and ice called the solar nebula. The matter in the nebula came together to form planetary bodies of different sizes and composition, with the Sun in the centre. Rocky planets formed closest to the Sun, the gas giants farther out, and icy bodies like Pluto farther still. This is because the nebula cloud was hotter toward the centre, just like the solar system today.

This temperature gradient influenced the composition of these planetary bodies, including the concentration of water. Lighter elements and compounds known as volatiles (things like water, carbon dioxide, and methane, which are stable as gas in our atmosphere) accumulated farther away from the Sun, concentrating in bodies like the gas planets. The rocky planets, like Venus, Earth, and Mars, formed where it may have been too hot for the water and other volatiles that form our hydrosphere and atmosphere to be present in high concentrations.

Some of the water in the Earth’s oceans came from condensation following the outgassing of water vapour from the surface of the planet, while some was delivered by impacting comets. An important question in recent years has been the relative importance of these two sources.

According to one school of thought, comets may have supplied the bulk of oceanic water during the heavy bombardment phase of the solar system, between about 4.5 and 3.8 billion years ago. If it is true, it increases the chances that organic matter, which is also found in comets, plays an important role in the origin of life. However, a study carried out by scientists at California Institute of Technology, the results of which were published in March 1999, 1 suggested that most of the Earth’s water probably did not have a cometary origin. Using Caltech’s Owens Valley Radio Observatory (OVRO) Millimeter Array, cosmochemist Geoff Blake and his team found that comet Hale-Bopp contains substantial amounts of heavy water, which is rich in the hydrogen isotope deuterium. If Hale-Bopp is typical in this respect and if cometary collisions were a major source of terrestrial oceans, it suggests that the Earth’s ocean water should be similarly rich in deuterium, whereas in fact it is not.

Where did the Earth’s water come from? There are two dominant theories.

The inside-out model proposes that the Earth formed with trace amounts of water structurally bonded to the minerals in the mantle. This water makes its way to the Earth’s surface through volcanic processes.

The outside-in model proposes that the Earth formed without water, which came with other volatiles from the meteorites or comets that bombarded the young planet. This water was probably mixed into the upper layers of the Earth and was later brought to the surface through volcanism.

Neither model is completely satisfactory, but most scientists support the first. Comets may have given the Earth a little bit of its water, and possibly as much as 20%, but nowhere near enough to fill the oceans. Meteorites, on the other hand, appear to be the building blocks of our planet because they’ve been found to have a composition similar to that of the early Earth.

The studies of meteorites allow scientists to estimate that as much as 0.5% of the weight of the Earth is made up of water. That may not sound like a lot, but considering how big the planet is, it’s more than enough to fill the world's oceans. The Earth’s mantle is estimated to contain from three to six times as much water as in the oceans, so it’s perfectly feasible that our surface water came from inside the Earth.

A tour of our planetary neighbours shows great variation: the Earth’s atmosphere consists mainly of nitrogen and oxygen, with trace amounts of other gases. The thick carbon dioxide atmosphere on the surface of Venus is 91 times denser than ours. Meanwhile, the surface density of the thin carbon dioxide atmosphere of Mars is a scant 1/150th of the Earth’s.


1. География [Электронный ресурс]. – Режим доступа: http://www.da viddarling.info/encyclopedia/. – Дата доступа: 11.02.2015.

2. How did the Oceans form? [Electronic resourse]. – Mode of access: http://www.amnh.org/learn/ocean/Resource1. – Date of access: 01.03.2015.

В статье представлены теории происхождения, возраста и эволюции океанов, рассматриваются особенности формирования океанов и появления воды в них, дается объяснение, почему вода в жидком состоянии есть только на планете Земля.

А.В. Егорова, Ю.С. Щербакова


Республика Беларусь, Брест, БрГУ имени А.С. Пушкина

Научный руководитель – Н.Н. Домбровская


THE RED BOOK OF BELARUS: PAST AND PRESENT



The increasing consumption of natural resources leads to environmental change. One manifestation of which is the sharp reduction in the number or total destruction of many species. The problem of preservation of biological diversity is extremely important. The extinction of each species is irreparable loss for nature and humanity, therefore, a reliable means of preserving the natural gene pool of each region is a primary environmental concern.

International Union for conservation of nature (IUCN) United and headed in 1948 work on the protection of wildlife of the state, scientific and public organizations of most countries of the world. Among his first decisions in 1949 was the creation of a Species Survival Commission or the Commission on rare species. The task of the Commission was to study the status of rare species of animals and plants, which was under threat of extinction, development and preparation of international projects and international conventions and treaties, the inventory of such species and to develop recommendations for their protection. The main goal of the Commission posed the creation of a worldwide list of animals which was in danger of extinction. Sir Piter Scott, chairman of the Commission, proposed to call list the Red Data Book to give it a defiant and capacious meaning, as red symbolizes danger signal.

Today the Red Data Books and lists is the most widely used in the field of nature protection of all countries of the world documents. It designed for focus on species with high conservation significance. Red book of the Republic of Belarus is a publication containing a list of rare and threatened with extinction on the territory of Belarus species (including subspecies) of wild animals and wild plants.

In 1979, according to the resolution of the Council of Ministers of the BSSR published the first edition of the Red Book of Belarus in Belarusian language [1, с. 9]. The book consisted of one volume and consisted of 80 species of animals and 85 species of plants.

The second edition of the Red Book of the Republic of Belarus taking into account generally accepted scientific principles for the protection and criteria for determining the status of rare and endangered species, as well as on the basis of the latest information on their distribution and ecology was included 182 species of animals, 180 plant species, 17 species of fungi and 17 of lichens. In second edition were added 107 species and 109 species of plants and at the same time excluded 5 species of animals and 14 species of plants, according to new data and criteria are not endangered and rare.

New edition of the national Red Data Book was prepared using advanced international approaches and criteria. Simultaneously regional specifics and opportunities for solving problems for the conservation of species was took into account. This approach is based on knowledge about current numbers and distribution of species, the trends of their dynamics, international conservation status and significance of the size of national populations in the global or European assessment of the abundance of the species.

A list of the third edition of the red book of the Republic of Belarus was prepared in accordance with the guidelines for application of criteria the IUCN Red Data Book at the national and regional levels, which was adopted by the Council of the International Union for the conservation of nature in October 2000. As a result of the universal application of new approaches in the preparation of the list of species for the third edition of the Red Book of Belarus 27 species of insects was added and 36 species was excluded, the total number was 70 species.  4 species of mammals was included an additional and 1 species was excluded, the total number amounted 17 species; 16 species of birds was added and 19 species was excluded, a total of 72 species; 2 species of bivalves was added and 1 species was excluded. 4 previously absent species of branchiopods and one at a time species of leeches, crustaceans, arachnids and amphibians was made [2, с. 7].

In this edition the list of rare plants and fungi was expanded to 60 species [3, с. 8]. Number of vascular plant species was increased to 173 (was excluded 24 and was added 41 new species), mosses up to 27 species (was added 12), algae up to 21 species (was added 12), lichen up to 24 species (was excluded 4, was added 11), fungi up to 29 species (was excluded 3, was added 15). Total 31 species was excluded and 91 new species was added.

Since 2007 there is electronic version of the Red Book. Work on its development was supported by the project of the UN development programme (UNDP) and Global environment facility (GEF) “Creating conditions for sustainable functioning of the system of protected wetlands in Belarusian Polesie” in close cooperation with the Ministry of natural resources and environment, NGO “Birdlife Fatherland”, the Royal society for the protection of birds (RSPB), the Institutes of zoology and botany of the National Academy of Sciences of the Republic of Belarus and the company “Medium” [4].

The Internet version includes two sections: plants and animals. Here you can find detailed information of 477 species of rare and endangered animals and plants, accompanied by photographs, drawings and maps. For each type provides information about the distribution, biology, numbers, causes of changes in the number and range taken and necessary measures of protection. The site also contains lists of extinct animals and plants (black list) and a list of animals and plants that require protection.

Red Book of Belarus contains information about the status of the species, the nature and extent of threats to its existence. One of the tasks of the Red Book is provide access to information about those species that are at highest risk of extinction.

The special legal status of rare species of animals and plants is determined by the legislation of the Republic of Belarus. The collection of plants, fishing and hunting of animals included in the Red book, is prohibited.

Red Book of the Republic of Belarus in accordance with generally accepted IUCN categories.All types are divided into 5 categories:

  1. Species that are endangered, salvation is impossible without the implementation of special measures.

  2. Species, the number of which is still relatively high, but decreases dramatically fast that in the near future may put them at risk of extinction.

  3. Rare species, which are not now threatened with extinction, but they occur in such small numbers or in limited areas.

  4. Species, the number and position of which is alarming, however, the lack of information about them does not assign them to any of the above categories.

  5. Restored state which is not of great concern today. But they are not yet commercial use and population control is required.

New proposal for inclusion of species in the Red Book of the Republic of Belarus are considered by the Academy of Sciences of the Republic of Belarus, the final entry in the Book is paid by the State Committee of the Republic of Belarus on ecology. After the elimination of the threat of extinction of a species it must be excluded from the Red Book of the Republic of Belarus. Suggestions and write about the exception are conducted in a similar manner.

The value of the Red Book in the first place, is that it is the basis for laws aimed at the protection of fauna and flora. In addition, it is a science-based program of practical measures for the preservation of endangered species. Finally, the invaluable role of the Red Book as a means of education and propaganda reasonable and respect for the animals and plants in general and rare, in particular.

  


  1. Зайчук, Г. И. Красная книга Республики Беларусь: правовые вопросы / Г. И. Зайчук. – Минск : Тесей, 2011. – 246 с.

  2. Красная книга Республики Беларусь: редкие и находящиеся под угрозой исчезновения виды диких животных ; под ред. Г. П. Пашкова. Минск : БелЭн, 2006. – 320 с.

  3. Красная книга Республики Беларусь: редкие и находящиеся под угрозой исчезновения виды дикорастущих растений ; под ред. Л. И. Хоружик. – Минск : БелЭн, 2005. – 456 с.

  4. Красная книга Республики Беларусь в Интернете [Электронный ресурс]. – Режим доступа: http://www.ptushki.org/info/press/item/27.html. – Дата доступа: 30.03.2015.


В статье речь идёт об особенностях появления и развития Красной книги в Беларуси. Авторы акцентируют внимание на том, когда и при каких обстоятельствах была впервые издана красная Книга Республики Беларусь. Статья затрагивает экологические проблемы, связанные с исчезновением животных и растительных видов, а также доказывает необходимость Красной книги для каждого члена общества.

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