The ecological crisis and the problems of modern civilization презентация

The aim of lecture is to provide
Information on ecological consequences of business activities of people under conditions of intensification of nature management

Brief content:
1. Anthropogenic impacts as geological and geochemical factors evolution of the biosphere
2. Ecological crisis and Physical, chemical and biological contamination of the environment
3. Climate change and Global ecological problems
4. Influence of state of the environment on human health

Introduction
Humanity is inexorably moving towards an ecological catastrophe - depletion of energy, mineral and land resources, destruction of the biosphere, and perhaps most of human civilization. Therefore, it became necessary to protect the human environment of his own influence on it. So modern civilization is in a state of profound ecological crisis. This is not the first time the environmental crisis in the history of mankind, but it may be the last.

Paleolithic Age
Major activities of
an early man were
harvesting and hunting
large animals
The biogenic period
covers the Paleolithic
The man fitted in
biochemical cycles,
worshipped the nature
and was its organic
part
First ecological and
economic crisis
The man became a
species-monopolist
And exhausted
resources of his
habitat

Neolith Age
The mankind began to create new artificial biogeochemical cycles
A new agrarian
period began in the interrelations of the mankind
with the nature
The man invented farming and animal breeding and changed ecological niche qualitatively
The number of mankind increased from millions to tens of millions

Post-neolithic ages
Expanding agricultural land our ancestors burnt forests. However, due to aimless farming the land became nonproductive very quickly, then new forests were burnt.
All this entailed changes in the life of while communities and their destruction:
Forests
Savanna
Prairie
Desert

The Neolithic Age
was a reason of the
second ecological
crisis.
Going to the north as glaciers melt, where new territories became empty
Mastering irrigated farming in the valleys of great south rivers – the Nile,the Tigris and the Euphrates
The mankind went out of the crisis by two ways as follows:

Periods
The next period, the industrial period included the period from 17th century up to the middle of 20th century. By the end of that period the number of the mankind drastically increased achieving five billion people.

The mankind came across a number of global ecological problems:
Drastic changes of the environment
Destruction of habitats led to the threat of extinction of two thirds of existing species
The fertility of soil worsened and reduced due to salinization and erosion
Huge quantities of industrial waste were discharged in the atmosphere and hydrosphere

Ecological problems are caused:
The pollution of the environment
Depletion of natural resources
Air and the World Ocean

Сontamination of the environment
Contamination is an excess of the natural level of various matters in the environment and introduction of new ones not characteristic for the environment.

In terms of their impact on living organisms contaminants are divided into:
PHYSICAL 2. CHEMICAL 3. BIOLOGICAL
Radioactive elements, heat pollution (excess of temperature), noise and low frequency vibration (infrasound) fall in the category of physical contaminants.
Carbon derivatives, sulfur, nitrogen, fluorine, solids, washing agents, detergents, plastics, pesticides, mineral fertilizers, organic matters and heavy metals are classified as chemical contaminants.
Pathogenic organisms. Viruses, seaweeds and increasing
some of animals as rats, dogs and cats fall in the category of biological contaminants.

Main contaminants in the industrial sewage are:
oil
oil products
non-ferrous metals

Many contaminants are very high toxic and cause various disorders in living organisms, in particular of a man, leading to various diseases, and the decrease in immunity. The fact being of a particular concern is that many contaminants, for example, salts of heavy metals, pesticides, detergents and others have mutafacient and carcinogenic activity causing congenital defects and cancerous diseases.

Climate Change
Climate change is yet another environmental problem that has surfaced in last couple of decades. It occurs due to rise in global warming which occurs due to increase in temperature of atmosphere by burning of fossil fuels and release of harmful gases by industries.
Climate change has various harmful effects but not limited to melting of polar ice, change in seasons, occurrence of new diseases, frequent occurrence of floods and change in overall weather scenario.

The greenhouse effect
The concentration of greenhouse gases (carbon dioxide, methane, nitrogen oxides and water vapour) in the atmosphere increases that results in climate warming.

Desertification is arising of landscapes close to desert with a rare vegetative cover as a result of human business activities, degradation and decrease in biological efficiency of the ecosystems.
Desertification

ACID RAIN
Acid rains are precipitation which contain sulphuric and nitric acids.

Global ecological problems. Acid rains

Burning coal is a leading cause of smog, acid rain, global warming, and air toxics.
Burning coal

Cars and Pollution
Emissions from an individual car are generally low, relative to the smokestack image many people associate with air pollution. But in numerous cities across the country, the personal automobile is the single greatest polluter, as emissions from millions of vehicles on the road add up. Driving a private car is probably a typical citizen's most "polluting" daily activity.
Sources of Auto Emissions
The power to move a car comes from burning fuel in an engine. Pollution from cars comes from by-products of this combustion process (exhaust) and from evaporation of the fuel itself.
Auto emissions

Biological diversity, or biodiversity, is the variety of the world's organisms, including their genetic diversity and the assemblages they form.
The decrease of a biological diversity

The biological diversity provides continuity of life in time, and maintains the biosphere’s functional structure and ecosystems being its components.

Destruction of the ozone layer is destruction of layers of the atmosphere (stratosphere) with the increased level of ozone (O3) located at the height 18-23 km that protects living organisms from hard ultraviolet rays.

Ultraviolet rays