Human-biosphere interaction

Anthropogenic pressure on the biosphere

The modern biosphere is experiencing colossal anthropogenic pressure (from Greek anthropos — human, genesis — origin). The key reason lies in the high population of the Earth and the enormous number of accompanying living organisms, primarily livestock.

In most cases, such a load exceeds the limits of resilience that natural ecosystems can withstand. As a result, the natural habitat is destroyed: lifeless deserts or artificial agroecosystems emerge in place of once-stable complexes.

Main directions of human negative impact on nature:

• Reduction of the area of natural ecosystems. Mass deforestation, plowing of steppe zones, and drainage of swamps lead to habitat fragmentation and degradation. Globally, this disrupts the most important environment-forming functions of the biosphere: oxygen production, synthesis and breakdown of organic matter, and soil protection.
• Loss of biological diversity.
• Disruption of biogeochemical cycles. Humans interfere with the natural course of the cycle of substances and radically change energy flows in nature.
• Global environmental pollution. This includes ozone depletion, climate shifts (greenhouse effect), acid rain, and eutrophication of water bodies.

Ecological crisis

Large-scale and aggressive intervention in nature has led humanity to an ecological crisis. This term refers to the critical mismatch between the scale of anthropogenic pressure and the ability of the biosphere to function stably while maintaining the constancy of vital environmental parameters (including the chemical composition of water, air, soil, and the level of biodiversity).

Key factors in the development of the crisis:

1. Super-intensive and irrational exploitation of natural resources.
2. Deep disruptions of the soil cover: accelerated erosion, salinization, pollution, and rapid depletion of the fertile humus layer.

Back in the 19th century, the French researcher J.B. Lamarck warned of the danger: humans are capable of making the planet completely uninhabitable and thereby destroying their own species. The only way out of the current situation is a global revision of our civilization's development course and a change in the principles of society's interaction with the biosphere.

Urboecosystems and their impact on the planet

A special product of human activity is urboecosystems (from Latin urbs — city). These are entirely artificial environments that arise due to high population concentration. Their main goal is to protect humans from adverse natural factors and increase the level of living comfort.

The process of urban growth and development (urbanization) transforms the Earth's surface much more strongly than any other form of human activity. The population of individual megacities has already exceeded 10 million people.

Features of the urban microclimate:

• Elevated temperature and humidity. They are always higher than in the surrounding rural suburbs.
• Reduced insolation. Urban air is oversaturated with pollutants that form fogs and reduce atmospheric transparency. Because of this, the amount of penetrating sunlight can be halved.
• Colossal energy release. Urban systems consume energy tens of thousands of times more intensively than non-urbanized areas.

The impact of the city is not limited to its physical boundaries. Depending on the level of industrial development and the size of the settlement, the zone of severe toxic pollution can spread for hundreds of kilometers from the source, suppressing surrounding natural landscapes.

Class and exam questions

What else to study on this topic

• Mechanisms of the greenhouse effect and acid rain formation
• Eutrophication of water bodies: causes, progression, and ecological consequences
• Ozone layer depletion as a result of atmospheric pollution
• Soil cover degradation processes: erosion, salinization, loss of humus
• The impact of natural ecosystem fragmentation on biodiversity reduction

Other topics in the "General Ecology" section

Prepared by WhiteCoat Pro faculty in accordance with the medical school curriculum. For educational purposes only.