Everything that surrounds us forms our environment. The environment includes the natural world around us - the land, water, air, plants, and animals - as well as the human-made world of our homes, cities, roads, and industries. Environment is thus made up of two broad components: the natural environment and the human environment, and these two are deeply interconnected.
The natural environment provides everything we need to live - air to breathe, water to drink, food to eat, and materials to build our homes. But humans also modify the environment, and these changes can be good or bad. This chapter introduces us to the different domains of the environment, the biosphere that supports life, and the ecosystems in which we live.
The term "environment" comes from the French word environner, which means "to surround." It includes all the things and conditions that surround us. The environment can be divided into two main parts:
The natural and human environments are not separate. Humans depend on the natural environment for their survival and modify it according to their needs. The interaction between the two is what makes the study of environment so important.
The natural environment is made up of four major domains:
The human environment includes human beings and the things they have created. Humans are the most important component of the environment because they have the ability to modify it. Human activities like farming, industry, transport, and settlement have transformed large parts of the natural environment.
The lithosphere is the solid, rocky crust of the earth. It is made up of rocks and minerals and covers the continents and the ocean floors. The lithosphere provides us with soil for agriculture, minerals for industry, and land for living. Landforms like mountains, plateaus, and plains are part of the lithosphere.
The hydrosphere consists of all the water on the earth - in oceans, seas, rivers, lakes, ice caps, and underground. Water covers about 71 percent of the earth's surface, and it is essential for all forms of life. The hydrosphere influences the climate and provides water for drinking, irrigation, industry, and transport.
The atmosphere is a blanket of gases that surrounds the earth. It extends to about 1,600 kilometres above the earth's surface, though most of its mass is within 30 kilometres of the surface. The atmosphere protects us from the sun's harmful ultraviolet rays, provides oxygen for breathing, and regulates the temperature of the earth.
The biosphere is the narrow zone of contact between the lithosphere, hydrosphere, and atmosphere, where all life exists. It is in the biosphere that plants and animals, including humans, live and interact. The biosphere is the highest level of ecological organisation and contains all the ecosystems of the earth.
An ecosystem is a system formed by the interaction of all living organisms (plants, animals, and humans) with each other and with their physical environment (land, water, and air). Every ecosystem is made up of two components:
Ecosystems can be large, like a forest or an ocean, or small, like a pond or a garden. The biosphere is made up of all the ecosystems of the earth. A change in any part of an ecosystem affects the whole system, which is why environmental balance is so important.
Humans are an important part of the environment and have always interacted with it. Early human beings lived in harmony with nature, taking only what they needed. But as civilisation grew, human activities began to modify the environment more and more.
Farming, the building of towns and cities, the clearing of forests, and the growth of industry have all changed the natural environment. Some of these changes have brought great benefits, but others have caused problems like pollution, deforestation, and climate change. This is why the study of the environment, and the need to protect it, has become so important today.
The environment provides all the resources that sustain human life, but these resources are limited. Forests are being cut down, water is being polluted, and the air is becoming more and more impure. To preserve the environment for future generations, we need to conserve its resources and use them sustainably.
Each of us can contribute to environmental conservation in small ways - by planting trees, saving water, reducing waste, and keeping our surroundings clean. Environmental awareness is not just about saving nature; it is about ensuring a healthy and liveable planet for ourselves and for all living beings.
| Domain | Description | Examples |
|---|---|---|
| Lithosphere | Solid crust of the earth | Mountains, plains, plateaus, minerals |
| Hydrosphere | Domain of water | Oceans, seas, rivers, lakes |
| Atmosphere | Layer of gases | Air, oxygen, nitrogen |
| Biosphere | Zone of life | All plants, animals and humans |
| Component | Type | Examples |
|---|---|---|
| Biotic | Living | Plants, animals, humans, microorganisms |
| Abiotic | Non-living | Soil, water, air, sunlight, temperature |
The environment is everything that surrounds us - the land, water, air, and life of the natural world, and the houses, roads, and societies of the human world. The four domains of the lithosphere, hydrosphere, atmosphere, and biosphere together sustain life on earth, and the biosphere contains all the ecosystems in which living beings interact with their surroundings. Humans have always depended on and modified their environment, but today the balance of the environment is under threat. Understanding and conserving the environment is therefore not just a scientific exercise but a duty that each of us owes to our planet and to future generations.