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The idea of biosphere appeared more than a century ago, but at first it found a little application, until it was developed by the Russian scientist V. I. Vernadsky. It is his conceptof the biosphere that we accept today.

The first living cell emerged between 4 billion and 3.8 billion years ago. At present biosphere includes vast numbers of plants, animals, and other life-forms of our planet, many of them are yet to be discovered. Biosphere is a relatively thin life-supporting layer around the Earth containing living organisms, which is strongly influenced in its composition, structure and energetic by the living organisms. The part of the biosphere containing the highest concentration of living matter – the Earth’s thin and fragile “film of life” – varies from a few meters in deserts and tundra to a hundred meters in a tropical forest region and oceans.

The biosphere is a complex system of energy use and material cycling. This system functions on energy flowing from the Sun and it gives off energy (primarily as heat) to space.

We can divide the biosphere into two parts, living and nonliving, or biotic and abiotic. The biotic part of the biosphere consisting of fauna and flora is known to be called biota. We can further divide the abiotic portion into three parts: the solid Earth or lithosphere, liquid water or hydrosphere, and the atmosphere.

Ecology is a branch of science which deals with the world of nature – including its human component – at certain levels of biological organization. It is the study of the living organisms interactions with each other and with their environment. Particular concern of the ecologists is with the “higher” levels of life organization: from populations to biosphere. The functional unit in ecology is the ecosystem because it comprises all interactions of communities with both their living (biotic) and their nonliving (abiotic) environments.

Ecology is a multidisciplinary science. Facts about ecological systems are drawn from biology, geology, chemistry, physics, and other sciences. Originally ecology was considered to be environmental biology. Modern ecology has to deal with environmental problems caused by human activities.

Geoecology is an interdisciplinary science, probably best translated as environmental sciences. Geoecology is not a synonym for physical geography. It is not dealing solely with the abiotic aspects of ecology. Geoecologists are rather “specializing in interdisciplinarity”, studying the interactions and interrelations abundant in our environment. Geoecologists work in the industry, for municipal, regional or federal authorities, in universities and research institutes, in foreign aid programs, and as freelance consultants or engineers. Broad education combined with high-quality specialized training allows geoecologists to work in fields such as environmental analytics, waste disposal, contaminated sites remediation as well as agriculture and forestry.

People have always affected the natural environment. But the population growth along with the industrial world economy during the last two centuries has increased the magnitude, complexity and rate of these modifications. Today environment is not just modified by human action: it is radically transformed. Global satellite observations of the Earth have revealed that about 60 % of land surface is to some extent damaged by industrial, agricultural, and other human activities, whereas no more than 40 % of land remains intact.

Humankind is entering a new era in its evolution characterised by a new relationship with nature. Understanding of how biosphere works, and how it reacts to the global environmental change is of fundamental importance.

Date: 2016-01-14; view: 1902