Natural resources are the materials and components that occur naturally in the environment and are utilised by humans for various purposes. These resources are essential for sustaining life, supporting economic activities, and maintaining ecosystems. Natural resources can be broadly categorised into two main types: renewable and non-renewable resources.
These resources are abundant and not likely to be depleted despite continuous use.
Examples include:
These resources are available in limited quantities and can be depleted with continuous and unchecked use. Exhaustible resources are further divided into two categories:
a) Renewable Resources: These resources can replenish themselves naturally over time, given responsible use.
Examples include:
b) Non-renewable Resources: These resources cannot naturally replenish themselves in human timescales. Once they are depleted, they are gone.
Examples include:
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Air is a mixture of gases that surrounds the Earth. It is composed of various gases, with nitrogen and oxygen being the most abundant. Other gases, such as carbon dioxide, argon, and trace amounts of other gases, also contribute to the composition of air. Air is essential for sustaining life on Earth and plays a crucial role in many natural processes.
The atmosphere is the layer of gases that surrounds the Earth and is held in place by gravity. It is divided into different layers based on altitude, each with distinct characteristics.
The main layers, from lowest to highest, are the troposphere, stratosphere, mesosphere, thermosphere, and exosphere. The atmosphere serves several important functions:
Air movement, known as wind, is a fundamental aspect of our atmosphere, influencing our daily experiences and weather patterns. The intricate dance of wind is driven by various factors, including temperature differentials, pressure variations, and Earth's rotation.
Imagine you're standing on a spinning carousel, and you throw a ball to someone across from you. To you, the ball appears to curve as it travels, even though you threw it in a straight line. This is similar to how the Coriolis Effect works. The Earth is like that spinning carousel, and anything that moves across its surface, like air masses or ocean currents, seems to curve due to the Earth's rotation.
The Coriolis Effect has a significant impact on various phenomena, especially large-scale movements like global wind patterns and ocean currents. It influences the way weather systems, like hurricanes, rotate and move. This effect is essential for understanding Earth's dynamic systems and how they interact with its rotation.
Air pollution refers to the presence of harmful substances in the air that can have adverse effects on human health, the environment, and ecosystems. These pollutants can originate from natural sources, such as volcanic eruptions and wildfires, or human activities, such as industrial processes, transportation, and burning of fossil fuels.
Air pollution can have a range of negative effects on human health, the environment, and the atmosphere:
Water is a colourless, odourless, and tasteless substance that covers about 71% of Earth's surface. It exists in various forms – solid (ice), liquid (water), and gas (water vapour) – and plays a fundamental role in supporting life on our planet. Water is a universal solvent, meaning it can dissolve a wide variety of substances, making it essential for many biochemical processes. It is also a major component of all living organisms.
The hydrosphere refers to the total amount of water on Earth's surface, including oceans, rivers, lakes, glaciers, groundwater, and even water vapour in the atmosphere. It's a dynamic system where water constantly moves and cycles through different forms and locations.
Water pollution refers to the contamination of water bodies – including rivers, lakes, oceans, and groundwater – by harmful substances. Pollutants can originate from various sources and have detrimental effects on aquatic ecosystems, human health, and the environment.
a) Point Sources of Water Pollution: Point sources are pollution discharge points that have a specific and identifiable location from which pollutants are directly released into water bodies. These sources are usually well-defined and relatively easier to monitor and regulate.
Because point sources have a fixed location, it is often possible to implement pollution control measures, such as installing treatment systems, before the pollutants are discharged into water bodies. Regulations and permits can be issued to ensure that the released pollutants meet acceptable standards.
Some examples of point sources include:
b) Non-point Sources of Water Pollution: Non-point sources are diffuse and scattered pollution inputs that do not have a specific discharge point. They result from the runoff of pollutants from various land surfaces, making them more challenging to identify and control.
Some examples of non-point sources include:
Efforts to prevent water pollution include:
Rainwater harvesting is a technique used to collect and store rainwater for various purposes. It involves the capture of rainwater from surfaces like rooftops, which is then stored in tanks or underground reservoirs. Rainwater harvesting can provide a sustainable source of fresh water in areas with low rainfall or limited access to surface or groundwater. It has several benefits:
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Soil is a complex mixture of minerals, organic matter, water, air, and living organisms that covers the Earth's land surface. It plays a crucial role in supporting plant growth, providing nutrients to organisms, filtering and storing water, and serving as a habitat for various organisms. Soil is formed through the process of weathering of rocks and the accumulation of organic material over time.
Soil formation is a gradual process influenced by various factors, including climate, parent material (rock from which soil forms), topography, organisms, and time. The process involves physical, chemical, and biological interactions:
Soil is a complex mixture of various components, each contributing to its overall characteristics and properties. The composition of soil includes:
The relative proportions of these components influence soil properties such as drainage, water-holding capacity, aeration, fertility, and suitability for plant growth.
Soils are categorised based on their particle size and properties:
Soil erosion is the process of detachment and movement of soil particles from their original location by agents like water, wind, and human activities.
Improper Agricultural Practices: Practices like ploughing along slopes, leaving fields bare between crops, and not implementing proper soil conservation measures can lead to soil erosion.
Soil erosion can have significant and far-reaching impacts on both the environment and human activities. Some of the key effects of soil erosion include:
Implementing effective soil erosion prevention measures is crucial for maintaining soil health and sustainability. Some key strategies for preventing soil erosion include:
Soil pollution refers to the contamination of soil with pollutants such as chemicals, heavy metals, pesticides, industrial waste, and sewage.
Soil pollution occurs due to various human activities that introduce harmful substances into the soil, affecting its quality and fertility. Some key causes of soil pollution include:
Soil pollution has far-reaching consequences for the environment, human health, and ecosystems. Some of the key effects of soil pollution include:
Biotic resources, also known as biological resources, are living organisms and organic materials that are derived from living organisms. These resources play a vital role in supporting life on Earth and provide various goods and services essential for human well-being. Biotic resources include a wide range of living organisms, from microorganisms to plants and animals.
Biotic resources can be broadly categorised into two main types:
Flora refers to the plant life found in a particular region or ecosystem. Plants are essential components of ecosystems, providing a multitude of resources and services to humans and other organisms.
Some key biotic resources derived from plants include:
Fauna refers to the animal life in a particular region or ecosystem. Animals provide a wide range of resources and services to humans and ecosystems.
Some important biotic resources derived from animals include:
Biotic resources are essential for ecosystem services that contribute to environmental stability and human well-being.
These services include:
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