Our Environment Chapter Notes | Footprints Class 7: Book Solutions, Notes & Worksheets PDF Download

Understanding the Environment

The term "environment" originates from the French word "environer," signifying 'to surround.' Essentially, the environment denotes the surroundings in which an organism inhabits. These surroundings can be either natural or artificial, encompassing:

• Natural Environment: This includes all living and non-living entities that naturally occur on Earth. For instance, forests, oceans, mountains, and wildlife form integral parts of the natural environment.
• Artificial or Human-Made Environment: It comprises elements resulting from the interaction between humans and nature. Examples of this type of environment are parks, dams, residential areas, and various infrastructures shaped by human activities.

In essence, the environment encompasses the entire set of surroundings that influence and shape the lives of living organisms, ranging from ecosystems to human settlements.

Natural Environment

• Physical Elements or the Abiotic Environment
• Biological Elements or the Biotic Environment

Abiotic Environment

• Comprises non-living components in the environment.
• It includes the lithosphere, hydrosphere, and atmosphere based on their physical characteristics.

Biotic Environment

• Encompasses all living organisms such as plants and animals.
• The biosphere forms where the lithosphere, hydrosphere, and atmosphere intersect, creating a zone that sustains life.

The Biosphere

• Includes both living and non-living elements.
• Spans from the deepest ocean depths (approximately 11,000 meters below sea level) to the highest mountain peaks (around 9,000 meters above sea level).

Interdependence of Organisms

• Within the biosphere, all living organisms, including producers, consumers, and decomposers, rely on each other for survival.
• Producers, also known as autotrophs like green plants, can create their own food by utilizing water, carbon dioxide, and sunlight.
• Most other living beings depend directly or indirectly on plants for their food and are categorized as consumers or heterotrophs.
• Consumers come in three types: herbivores, carnivores, and omnivores.
• Decomposers, such as bacteria, play a crucial role in breaking down dead animals and plants.
• Energy is transferred between organisms through food chains, which interconnect to form food webs. These webs are finely balanced, meaning that the destruction of one link can have cascading effects on other organisms.

An Ecosystem

• An ecosystem represents a natural unit comprising both non-living (such as land, water, and air) and living elements (like plants and animals).
• It forms a distinct system through the interaction of all living organisms (biotic components) that rely on each other and the physical environment (abiotic component) they inhabit, like forests, grasslands, and deserts.
• The biosphere denotes the global ecosystem, while individual habitats like forests, deserts, or ponds, with their specific living communities, are known as regional ecosystems.
• The environment maintains a dynamic nature due to constant interactions between living and non-living components. Changes in the abiotic environment lead to alterations in the biotic environment, affecting species' numbers and types. Living organisms also adapt their surroundings to their needs.

Human Environment

• The Human Environment

  The human environment refers to human beings and their interactions with the surroundings. It includes all the resources essential for human prosperity and survival.

• Human Interaction with Nature

  In the past, early humans coexisted harmoniously with nature. However, as science, technology, industrialization, and agriculture progressed, urbanization and overpopulation emerged, disrupting this balance.

• Environmental Degradation

  Human activities like deforestation, logging, and mining have become unsustainable over time, leading to accelerated environmental degradation. These practices have significantly impacted ecosystems and biodiversity.

Understanding Global Warming and Sustainable Development

An increase in the concentration of carbon dioxide in the atmosphere, primarily due to transportation and industrial activities, has resulted in global warming. Global warming refers to the gradual increase in the average temperature of the Earth's atmosphere and oceans. This phenomenon commenced in the late 19th century and persists to this day.

Effects of Global Warming:

• Rise in sea levels due to melting glaciers
• Reduction in snow coverage
• Increase in the frequency of extreme weather events
• Ecological and social transformations

It is crucial to prioritize sustainable development in society, ensuring that present needs do not compromise the ability of future generations to fulfill their essential requirements. Establishing a sustainable society encompasses various actions, including:

Key Aspects of Sustainable Development:

• Managing population growth
• Utilizing renewable energy sources
• Prudent utilization of resources
• Implementing waste recycling practices