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1396 materials

Found 1396 materials

The Fate of Baturyn

The fate of Baturyn has been prepared for us. We must realize this, keep it in mind, and act with this scenario in view. And the most important thing in such a situation is to keep moving, without stopping.

Feb 15, 2019 News

Ecology: Biology of Interactions. II-09. Biogeochemical Cycle of Phosphorus

The phosphorus cycle is much less regulated than the just-considered carbon and nitrogen cycles because phosphorus lacks an exchange reservoir in the atmosphere. Phosphorus is the primary element that controls the productivity of aquatic communities. In the experiment with pond halves, where one of them...

Jan 07, 2019 Lecture

Ecology: the biology of interaction. II-08. Biogeochemical cycle of Sulfur

Sulfur — a relatively abundant (fifteenth by chemical abundance) element in the Earth's crust, occurring in various oxidation states. It is a necessary component of proteins (0.8-2.4%), entering into their composition in the form of sulfhydryl groups (-SH) and disulfide groups (-S-S-). Upon destruction...

Jan 07, 2019 Lecture

Ecology: Biology of Interaction. II-07. Biogeochemical Cycle of Nitrogen

The BGC cycle of Nitrogen is more complex than the Carbon cycle. It is also extremely important for living organisms. Although nitrogen is more abundant in the atmosphere than other gases, its incorporation into living matter is a far more complex task than the fixation of Carbon from carbon dioxide …

Jan 07, 2019 Lecture

Ecology: Biology of Interaction. II-06. Biogeochemical Cycle of Carbon

Carbon is the foundation of organic compounds, and therefore the Carbon cycle is of particular significance for living organisms. The most important feature of this cycle is the presence of CO2 reserves — carbon dioxide — in the atmosphere, from which living organisms can draw. The movement of Carbon through …

Jan 07, 2019 Lecture

Ecology: Biology of Interactions. II-05. Energy Sources for Biogeochemical Cycles

Movement of elements in the biosphere is maintained by three main energy sources (“drive belts” of biogeochemical cycles): solar energy transformed by hydrosphere and atmosphere in the hydrological cycle; solar energy stored in organic matter by photosynthesis; and chthonic (internal Earth) energy driving plate tectonics and volcanism.

Jan 06, 2019 Lecture

Ecology: biology of interaction. II-04. Biogeochemical cycles

Biogeochemical cycle (BGC-cycle) refers to a relatively closed set of pathways for the transformation and movement of substances through living organisms and their environment. Biogeochemical cycles are called this because both biological and geochemical processes are involved in their functioning. Conven...

Jan 06, 2019 Lecture

Ecology: biology of interaction. II-03. Gaia hypothesis (metaphor)

In 1972, James Lovelock and Lynn Margulis proposed the so-called «Gaia hypothesis» — the conception of Earth as a superorganism that maintains its homeostasis. As Lovelock later indicated, he and Margulis independently arrived at ideas previously expressed by James Hutton in the 17th century...

Jan 05, 2019 Lecture