Environmental Ecosystem Studies Notes

UNIT 1: Multidisciplinary Nature of Environmental Studies

• Environmental studies addresses every issue affecting organisms and the environment.

• It emphasizes a multidisciplinary approach to understand the natural world and human impacts on it.

• It is an applied science focused on practical solutions for sustainable human civilization using Earth's resources.

• It involves the complex relationships among people, animals, organisms, water, soil, air, and the environment.

• It requires inputs from various disciplines like biology, botany, zoology, soil science, technology, oceanography, atmospheric science, economics, sociology, anthropology, and ethics.

• Environmental studies educates people about preserving environmental quality.

Definition of the Environment

• Environment encompasses the social, cultural, and physical conditions that affect the survival, growth, and development of people, animals, and plants.

• It includes both living (biotic) and non-living (abiotic) components of the Earth.

Four Segments of the Environment

1. Atmosphere:

   • The air envelope surrounding the Earth.

   • Sustains life and protects from the environment of outer space.

   • Contains essential gases like $O<em>2$ for humans and animals and $CO</em>2$ for plants.

2. Hydrosphere:

   • Covers over 75% of the Earth's surface.

   • Includes seas, rivers, oceans, lakes, ponds, and streams.

3. Lithosphere:

   • The solid component of the Earth.

   • Includes soil, earth, rocks, and mountains.

4. Biosphere:

   • Consists of the atmosphere, lithosphere, and hydrosphere.

   • Supports biotic and abiotic life systems by providing air ($O<em>2$, $N</em>2$, $CO_2$), land (minerals, salts, nutrients), and water (dissolved oxygen, salts).

Need for Public Awareness

• Public awareness is critical to address environmental degradation.

• Environmental degradation, if uncorrected, could lead to the extinction of life.

• Industrialization and increasing population have led to rapid resource utilization and environmental degradation.

• Protecting the environment requires active participation from both the government and the people.

• Protecting the environment is more economically viable than cleaning up damage.

• Mass media (newspapers, radio, television) plays a vital role in raising awareness.

• Institutions like BSI (Botanical Survey of India, 1890), ZSI (Zoological Survey of India, 1916), and WII (Wildlife Institute of India, 1982) contribute towards environmental awareness.

Major Environmental Challenges

• Population:

  • A large population growing at 2.11% annually.

  • India accounts for 16% of the world population with only 2.4% of the land area.

  • Limiting population growth is a significant challenge.

  • Linking population growth to resource base is necessary for sustainable development.

• Poverty Alleviation:

  • Poverty and environmental degradation are interconnected.

  • A majority of people depend on natural resources for basic needs.

  • Environmental degradation disproportionately affects the poor.

  • Addressing poverty is essential for tackling environmental challenges.

• Agricultural Growth:

  • Sustaining agricultural growth without environmental damage is crucial.

  • Fertilizers and pesticides cause soil and water pollution.

  • Intensive agriculture leads to soil salinity and structural damage.

• Protecting Ground Water from Pollution:

  • Increasing demand for water due to agriculture, industries, urbanization, and population growth.

  • Depletion of groundwater table.

  • Pollution from community wastes, industrial effluents, fertilizers, and pesticides.

  • Restoring water quality and conserving water resources are necessary.

  • Rainwater harvesting and water management can help.

• Development and Forests:

  • Forests provide raw materials and act as river catchments.

  • Dam construction leads to forest submergence, displacement of people, and damage to flora and fauna.

  • Political conflicts and scientific debates arise from dam projects.

  • Shrinking forests due to agriculture and other uses.

  • Integrating traditional knowledge of tribal communities with modern forestry practices is essential for conservation and afforestation.

• Degradation of Land:

  • Out of 329 mha of land, only 266 mha has potential for production.

  • 143 mha is agricultural land, and 85 mha suffers from soil degradation.

  • 40 mha are unproductive.

  • Remaining 83 mha is forest land, half of which is denuded.

  • Livestock grazing on limited pasture land leads to overgrazing.

  • Water and wind erosion cause further degradation.

• Reduction of Genetic Diversity:

  • Conserving genetic diversity is urgently needed.

  • Wild genetic stocks are disappearing.

  • Protected areas may isolate populations.

• Evil Consequences of Urbanization:

  • Nearly 27% of Indians live in urban areas.

  • Urbanization and industrialization create environmental problems.

  • A significant percentage of urban dwellers live in slums.

  • Limited sewerage and treatment facilities in towns and cities.

• Air and Water Pollution:

  • Outdated industrial technologies and inadequate waste treatment facilities.

  • Many cities and industrial areas are heavily polluted.

  • Effective implementation of environmental regulations requires resources, expertise, and public support.

Public Awareness and Responsibility

• Environmental degradation requires collective action.

• Public awareness is essential for creating a sustainable environment.

• Print and electronic media can influence public opinion.

• NGOs can play a role in creating awareness from grassroots levels to policy-making.

• The environment is an integration of living and non-living organisms (water, air, soil, minerals, wildlife, etc.).

• Limited natural resources and human activities cause environmental degradation.

Activities for Creating Public Awareness

• Join nature study groups (WWF-I, BNHS).

• Read environmental articles and periodicals (Down to Earth, WWF-I newsletter, BNHS, Hornbill, Sanctuary magazine).

• Discuss environmental issues with friends and relatives.

• Join local movements for saving trees and reducing plastic use.

• Practice the 3 Rs: reduce, reuse, & recycle.

• Promote civic sense and hygiene (no spitting/chewing tobacco, no garbage, no urinating in public places).

• Participate in events on World Environment Day and Wildlife Week.

• Visit national parks or spend time in natural habitats.

Ecosystem

• An ecosystem is a structural and functional unit of ecology.

• Living organisms interact with each other and the surrounding environment.

• It is a chain of interactions between organisms and their environment.

• A.G. Tansley coined the term "Ecosystem" in 1935.

Structure of the Ecosystem

• Characterized by organization of biotic and abiotic components.

• Includes distribution of energy and climatic conditions.

• Split into two main components:

  • Biotic Components

  • Abiotic Components

• The biotic and abiotic components are interrelated.

• It is an open system where energy and components can flow throughout.

Biotic Components

• All living components in an ecosystem.

• Based on nutrition, categorized into autotrophs, heterotrophs, and saprotrophs (decomposers).

  • Producers:

    • Autotrophs such as plants.

    • Produce food through photosynthesis.

    • Other organisms rely on them for food.

  • Consumers:

    • Heterotrophs that depend on other organisms for food.

    • Classified into primary, secondary, tertiary, and quaternary consumers.

      • Herbivores (Primary consumers):

        • Rely on producers for food.

        • Example: Rabbit, Cows etc.

      • Carnivores (Secondary consumers):

        • Depend on primary consumers for energy.

        • Example: Lizard, Fox etc.

      • Top Carnivores (Tertiary consumers):

        • Depend on secondary consumers for food.

        • Can be carnivores or omnivores.

      • Quaternary consumers:

        • Prey on tertiary consumers for energy.

        • Usually at the top of a food chain with no natural predators.

  • Decomposers:

    • Saprotrophs such as fungi and bacteria.

    • Thrive on dead and decaying organic matter.

    • Essential for recycling nutrients to be reused by plants.

Abiotic Components

• Non-living component of an ecosystem.

• Includes air, water, soil, minerals, sunlight, temperature, nutrients, wind, altitude, turbidity, etc.

• Inorganic substances involved in mineral cycles:

  • Example: C, N, P, K, S, H etc.

• Organic substances present in biomass or environment:

  • Form the living body and influence the functioning of the ecosystem.

  • Example: Carbohydrate, proteins, lipids, humus etc.

• Climatic factors having strong influence on the ecosystem.

Types of Abiotic Components

1. Water

   • Covers more than 70% of the earth‘s surface.

   • Critical for survival.

2. Atmosphere

   • Contains oxygen and carbon dioxide for animals and plants.

   • Used to produce carbohydrates, other organic materials, DNA, and proteins.

3. Sunlight

   • Primary source of energy.

   • Plants require it for photosynthesis.

4. Soil

   • Composed of rocks and decomposed plants and animals.

   • Critical abiotic factor.

Functions of Ecosystem

1. Regulates essential ecological processes, supports life systems, and renders stability.

2. Responsible for cycling nutrients between biotic and abiotic components.

3. Maintains balance among trophic levels.

4. Cycles minerals through the biosphere.

5. Abiotic components help in the synthesis of organic components involving energy exchange.

Functional Units or Components of Ecosystem

• Productivity: Rate of biomass production.

• Energy flow: Sequential process through which energy flows from one trophic level to another.

• Decomposition: Breakdown of dead organic material.

• Nutrient cycling: Nutrients are consumed and recycled back in various forms for utilization by organisms.

Food Chain

• The order of living organisms in a community where one consumes the other to transfer energy.

• A chain of organisms through which energy is transferred.

• Starts with a producer like plants.

• Consumers eat other organisms.

• Plants are called producers because they produce their own food through photosynthesis.

• Animals are called consumers because they depend on plants or other animals for food to get energy.

• Each organism gets energy from the one at the level below.

• Not all the energy at one stage of the chain is absorbed by the organism at the next stage.

Trophic Levels in a Food Chain

• Different stages of feeding positions in a food chain.

Organisms are Categorized Under Different Groups

• Producers (First Trophic Level):

  • Autotrophs that prepare their own food.

  • Plants, one-celled organisms, bacteria, algae use photosynthesis to prepare food.

• Consumers:

  • Depend on others for food.

    • Primary Consumers (Second Trophic Level):

      • Herbivores that eat the producers.

      • Deer, turtle, and many types of birds.

    • Secondary Consumers (Third Trophic Level):

      • Eat plants and herbivores.

      • Carnivores and omnivores.

      • Example: Snake that eats a mouse.

    • Tertiary Consumers (Fourth Trophic Level):

      • Animals that eat other carnivores.

      • Example: Secretary bird and King Cobra.

• Decomposers:

  • Break down dead organic material and wastes.

  • Fungi and bacteria use chemical energy in dead matter and wastes to fuel their metabolic processes.

  • Detritivores (detritus eaters or debris eaters).

Food Web

• A network of interconnected food chains forming feeding relationships amongst different organisms in a biotic community.

• Multiple chains involving the same food resource. This is possible when the resource is at the lower tropic level.

• A food web comprises all the food chains in a single ecosystem.

• Each living thing is part of multiple food chains.

• A single food chain is the single possible path that energy and nutrients may make while passing through the ecosystem.

• All the interconnected and overlapping food chains in an ecosystem make up a food web.

• Plants are the foundation of all ecosystem and food chains, sustaining life by providing nourishment and oxygen needed for survival and reproduction.

• The food web provides stability to the ecosystem.

• The tertiary consumers are eaten by quaternary consumers. For example, a hawk that eats owls.

• Each food chain ends with a top predator and animal with no natural enemies (such as an alligator, hawk, or polar bear).

Ecological Pyramids

• A graphical representation to show the number of organisms, biomass, and productivity at each trophic level.

Types of Ecological Pyramids

1. Pyramid of Numbers:

   • The number of organisms in each trophic level is considered.

   • Usually upright, except in detritus food chains.

   • Represents the number of individuals at each tropic level.

     • Aquatic and Grassland Ecosystems:

       • Upright shape, as producers are more than primary consumers.

     • Forest Ecosystem:

       • Partly upright or spindle type.

       • Fewer producers supporting more herbivores who support fewer carnivores.

     • Parasitic Food Chain:

       • Inverted shape.

       • Producers are least in number and predators are greater in number as we move up the food chain.

2. Pyramid of Biomass:

   • Takes into account the amount of biomass produced by each trophic level.

     • Upright Pyramid of Biomass:

       • Ecosystems on land have large base of producers.

       • Maximum biomass of autotrophs or producers.

     • Inverted Pyramid of Biomass:

       • Aquatic ecosystems often have an inverted pattern.

       • Phytoplankton (producers) grow rapidly but are smaller than zooplankton (consumers).

3. Pyramid of Energy:

   • Always upright, as energy flow is unidirectional.

   • Energy is lost into the environment at each trophic level.

Types of Ecosystem

• Can be as small as an oasis or as big as an ocean.

Types of Ecosystems

1. Natural Ecosystems:

   • Operate by themselves under natural conditions without human interference.

     • Terrestrial Ecosystem

     • Aquatic Ecosystem

2. Artificial Ecosystems:

   • Controlled and manipulated by humans.

     • Agriculture Ecosystem

     • Aquaculture Ecosystem

Terrestrial Ecosystems

• The ecosystem of different land forms.

  • Rain-forest Ecosystem:

    • Dense environment due to rainfall.

    • Varieties of plants & animals.

  • Desert Ecosystem:

    • High flora & fauna but less variety.

    • Extreme temperature, sunshine, less water.

    • Plants conserve water (e.g., cactus).

    • Animals like camels, reptiles, insects.

  • Forest Ecosystem:

    • Varieties of flora and fauna.

    • Tropical: large variety of vegetation.

    • Temperate: coniferous and deciduous.

  • Tundra Ecosystem:

    • Limited life due to harsh environment.

    • Land covered with snow most of the year.

  • Savanna Ecosystem:

    • More rainfall than deserts.

    • Supports life of flora & fauna.

  • Grassland Ecosystem:

    • Mainly grasses, shrubs & trees.

    • Pleasant climate.

    • Grazing animals, herbivorous, insectivorous.

  • Mountain Ecosystem:

    • Variety of plants & animals.

    • Challenging survival due to alpine vegetation.

    • Animals have long, thick fur and hibernate.

Aquatic Ecosystems

• Found in different water bodies.

  • Marine Ecosystem:

    • Covers almost 70% of the Earth‘s surface.

    • Water is the main component with minerals & salt dissolved.

    • Many organisms: sharks, algae, corals etc.

  • Freshwater Ecosystem:

    • Covers almost 0.8% of the Earth‘s surface.

    • Lentic (stagnant): ponds, lakes.

    • Lotic (fast-flowing): rivers.

    • Wetlands: saturated land.

Functional Components of Ecosystem

• Abiotic factors: Non-living things (air, water, soil, sunlight, temperature).

• Biotic factors: All the living things.

  • Producers: Organisms preparing its own food (green plants, autotrophs).

  • Consumers: Organisms obtaining energy from other organisms (all animals).

  • Decomposers: Organisms feeding on dead and decaying matter (fungi, bacteria).

Biogeochemical Cycle

• Movement of nutrients and elements between biotic and abiotic factors.

• The term comes from "bio" (biosphere), "geo" (geological components), and "chemical" (elements moving through a cycle).

• Earth obtains energy from the sun.

• Major elements: Carbon, Hydrogen, Nitrogen, Oxygen, Phosphorus, Sulphur.

• Elements are recycled through biotic and abiotic components of the ecosystem.

• Abiotic components: atmosphere, hydrosphere, and lithosphere.

Types of Biogeochemical Cycles

1. Gaseous cycles: Carbon, Oxygen, Nitrogen, and the Water cycle.

2. Sedimentary cycles: Sulphur, Phosphorus, Rock cycle

Carbon Cycle

• Process where carbon compounds are interchanged among the biosphere, geosphere, hydrosphere, and atmosphere.

• Plants absorb carbon dioxide from the atmosphere through photosynthesis and convert it into oxygen and carbohydrates.

• Animals breathe in oxygen, eat plants, and use carbon of carbohydrates to build their own tissues.

• Animals return carbon dioxide into the air through breathing and decomposition.

• When we burn fossil fuels like oil, the carbon combines with atmosphere oxygen to form carbon dioxide.

Carbon Exists in the Non-living Environment as

• Carbon dioxide in the atmosphere, dissolved in water as bicarbonates.

• Carbonate rocks (like limestone $CaCO_3$).

• Deposits of coal, petroleum and natural gas derived from living things.

• Dead organic matter (humus in the soil).

Carbon Enters the Biotic World Through the Action of Producers

• Primarily photoautotrophs (like plants) using light energy to convert carbon dioxide to organic matter.

• Chemotrophs (like bacteria) to a small extent.

Carbon Returns to the Atmosphere By

• Respiration (as $CO_2$).

• Burning or combustion of fossil fuels.

• Decay of animal and plants body.

Nitrogen Cycle

• Biogeochemical process in which nitrogen is circulated from the atmosphere to the living organisms and later back to the atmosphere.

• Living organisms require nitrogen for the synthesis of nucleic acid and proteins.

• Atmosphere contains almost 78% of nitrogen in an inert form ($N_2$).

• Nitrogen cannot be used unless converted to ammonia, nitrates, etc.

• The nitrogen cycle is a cyclic process from inorganic form in the atmosphere and back again.

• The nitrogen cycle contains several steps: nitrogen fixation, nitrification, assimilation, ammonification and denitrification.

Steps in the Nitrogen Cycle

1. Nitrogen Fixation

   • Conversion of atmospheric inert nitrogen into a usable form.

     • Atmospheric Nitrogen Fixation: Lightning converts nitrogen gas to nitrates.

     • Biological Nitrogen Fixation: Nitrogen-fixing bacteria (e.g., in roots of legumes) convert nitrogen to ammonia.

2. Nitrification

   • Conversion of ammonia into nitrates by nitrifying bacteria.

3. Assimilation

   • Nitrates absorbed by plant roots to make amino acids and proteins.

4. Ammonification

   • Conversion of dead organic matter into ammonia through bacteria and fungi.

5. Denitrification

   • Denitrifying bacteria convert nitrates to free nitrogen, which escapes to the atmosphere.

Sulphur Cycle

• Sulphur is an abundant element, found in all kinds of proteins.

• Plants absorb sulphur-containing amino acids directly.

• Sulphur enters the atmosphere through natural and human sources (oxides of sulphur).

• It reacts with rain and falls into earth as acidic sulphate deposition.

• Sulphate is absorbed by plants for making amino acids, protein etc.

• Animals consume plants to maintain their health, as sulphur is important for enzymes and proteins.

• A simplified version of the transformations and chemical species in a sulphur cycle:

  • (i) Sulphate ($SO_4^{-2}$) is reduced to hydrogen sulphide by sulphate reducing bacteria.

  • (ii) Some sulphate is assimilated by organisms to form cell components such as amino acids and cofactors.

  • (iii) Organic sulphur is converted to $H_2S$ upon minerization.

  • (iv) $H_2S$ is transformed to elemental sulphur (S).

  • (v) Sulfide oxidizing bacteria convert S into $SO_4^{-2}$.

  • (Vi and Vii) Anoxygenic phototrophic bacteria also convert $H<em>2S$ to $SO</em>4^{-2}$ via elemental sulphur.

  • (Viii) Sulphur reducing bacteria transform back the elemental sulphur to $H_2S$.

  • ix) Some $H_2S$ complexes with iron to form black FeS precipitates, whose recycling is slow.

Natural Resources

• Resources existing on the planet independent of human actions.

• Found in the environment and developed without human intervention.

• Examples: air, sunlight, water, soil, stone, plants, animals and fossil fuels.

Classification of Natural Resources

• Based on origin, level of development and uses, stock or deposits, and distribution.

1. Based on Origin:

   • Living or Biotic Resources: Come from living things or organic materials (plants, animals, fossil fuels).

   • Non-living or Abiotic Resources: Derived from nonliving or inorganic materials (air, sunlight, water, minerals).

2. Based on Deposit or Stock:

   • Renewable: Available in infinite quantity and can be used repeatedly (forest, wind, water).

   • Non-Renewable: Limited in abundance and availability may run out in the future (fossil fuels, minerals).

Renewable vs. Non-Renewable Natural Resources

Most Important Natural Resources

1. Air: Clean air is essential for survival.

2. Water: Most of the Earth is covered in water, with only 2% is fresh water. Initiative should be taken to regulate water usage.

3. Soil: Necessary for plant growth.

4. Iron: Used for building transportation, weapons, and buildings.

5. Forests: They provide clean air and preserve the ecology of the world; Trees are being cut for construction projects.

Types of Natural Resources

1. Water

2. Mineral

3. Land

4. Energy

Water Resources

• Sources of water that are useful or potentially useful to humans.

• Essential for the existence of life (plants, animals, and humans cannot survive without it).

• Used in agriculture, household, industrial, recreational and environmental activities.

• Essential for economic growth, environmental stability, biodiversity conservation, food security and heath care.

Significance and Problems Arising from Disturbances to the Water Cycle

The Water Cycle

• Describes the continuous movement of water above and below the surface of the earth.

• Driven by the sun.

• The sun heats water in seas and oceans, which evaporates into the air.

• Rising air currents take the water vapours into the atmosphere and condense them into clouds, which then collide, grow, and fall out of the sky as precipitation.

• Some precipitation falls as snow, and can accumulate as ice caps and glaciers.

• Most water falls back into the oceans or onto land as rain where the water flows over the ground as surface run-off.

• Some run-off is stored as fresh water in lakes, infiltrates deep into the ground and replenishes aquifers.

• Some groundwater finds openings in the surface of land and freshwater springs come out.

• Some rainwater flows through rivers back into the ocean, where the water cycle begins again.

Sources of Water

• 97.5% of water on the earth is salt water in oceans.

• Only 2.5% is fresh water.

  • Surface Water: Water in a lake, river or freshwater wetland

  • Groundwater: Fresh water located in the pore space of soil and rocks

  • Ice Caps and Glaciers: Fresh water from ice caps and glaciers is relatively inaccessible.

Causes of Water Crisis in the World

• Growing population and better lifestyles.

• Freshwater resources are reduced by pollution.

• Increase in extreme weather conditions.

Recently

• Climate change will account for about 20% of the increase in global water scarcity

• 50% of the population of developing countries are exposed to polluted water sources

Overutilization of Surface and Ground Water

• Water scarcity is a burning global issue.

• Continuous overutilization of surface and ground water has led to virtual water scarcity.

• The depleting sources for high growth in human population over the centuries and increased man-induced water pollution across the world have created unforeseen water scarcity around the globe.

• Groundwater is the major source of water in many parts of the world, but there has been continuous depletion of this source due to its overexploitation.

Consequences of Overutilization

• Water scarcity is an important topic in international diplomacy.

• According to World Health Organization (WHO) sources, a combination of rising global population, economic growth and climate change means that by 2050 five billion (52%) of the world‘s projected 9.7 billion people will live in areas where fresh water supply is under pressure.

• Researchers expect about 1 billion more people to be living in areas where water demand exceeds surface-water supply.

Climate Change

• Climate change can have an impact on the drainage pattern and hydrological cycle thereby severely affecting the surface and groundwater availability.

• Temperature increase affects the hydrological cycle by directly increasing evaporation of available surface water and vegetation transpiration.

• As a result, precipitation amount, timing and intensity rates are largely affected. It impacts the flux and storage of water in surface and subsurface reservoirs.

Floods & Draughts

• Amount of rainfall varies from one place to another depending on the location of the place and heavy rains lead to floods and droughts sets in when a particular region goes without rain for a long period of time.

• Frequent floods and droughts are mostly due to climate change and global warming.

Importance of Water

• Next to air, water is the most essential thing for survival.

• We use water to avoid dehydration.

• Water is also helpful in maintaining the relatively constant body temperature through the homeostasis process.

• Water helps in the digestion process.

• Different enzymes facilitate this digestion process and different food products, after being broken down to simple molecules are solubilized in water.

• Oxygen gas is also dissolved in water, which helps in the respiration process of many organisms those who live in water.

Life is impossible without water. It is needed for health, ecosystem services, economic development, poverty reduction, and protection of greenery, production of food and imparting of aesthetic beauty.

Water Conservation

• Water Conservation is the most cost-effective and eco-friendly way to reduce our demand for Water.

Need for Water Conservation

• The poor do not have ac- cess to safe drinking water. More than 4000 children are dying every day as a result of diarrhoeal diseases caused from unsafe drinking water.

Measures to Water Conservation

• (a) Recharge groundwater by harvesting rainwater.

• (b) Use water wisely for household, agricultural and domestic purposes.

• (c) Reuse water whenever possible.

• (d) Avoid transmission and distribution losses by checking leaks in pipes, hoses, etc.

• (e) Prevent flow of untreated sewage to lakes and rivers.

• (f) Collect water by building dams and reservoirs, and digging wells.

• (g) Use drip irrigation, precision sprinklers for agriculture. Practice organic farming.

• (h) Adopt fairer policies for treatment, access and pricing of water.

• (i) Prevent flow of industrial effluents to natural water resources to avoid water pollution.

• (j) Do protect forests to protect rivers, lakes, wells and other sources of water.

Major Factors Responsible for Water-Quality Degradation

• (i) Insufficient and incomplete treatment of domestic and industrial waste- water

• (ii) Eutrophication

• (iii) Pathogens, and pesticide contamination

• (iv) Stagnation of domestic sewage and contamination of groundwater

Water-Borne Diseases

• Water-borne diseases are illnesses caused by consuming water contaminated by pathogenic microorganisms.

• Avoid drinking untreated water, avoid consuming undercooked food, maintain good personal hygiene, and educate for clean sanitation are the ways to prevent water- borne diseases.

Fluoride Problem in Drinking Water

• At low concentrations in drinking water, fluoride has beneficial effects on teeth.

• But excessive exposure to fluoride in drinking water can give rise to number of adverse effects. (damages teeth, bone, brain and endocrine system.)

Source of Fluoride

• (a) Flouridated water supplies

• (b) Food processed with flouridated water

• (c) Mouthwash enhanced with fluoride

• (d) Toothpaste enhanced with fluoride

• (e) Food supplements

Mineral Resources

Natural resources in the form of minerals are known as mineral resources.

Minerals and Their Classification

• Minerals are naturally occurring, inorganic, solid, crystalline substances which contain a specific composition of elements and is classified into Metallic and non-metallic forms.

• A mineral which can be extracted and processed at a profit is known as an ore.
  *almost all rocks are made of minerals. They have high aesthetic value, e.g. gemstones and have natural resource value. (raw materials for making glass, plaster, etc.)

Environmental Effects of Extracting and using Mineral Resources

*Extraction and use of mineral resources impacts on forest, land, occupation, water, ecological functions, rehabilitation of population. Including the loss of flora and fauna.

Conservation of Mineral Resources

Encourage use of improved technologies so as to reduce waste generation, recycling of metals, research for ecofriendly alternatives for fossil fuels and provide solutions for the sustainable use of mineral resources.

Land Resources

• A naturally occurring finite resource.

• It provides the base for survival of living things and the store house for minerals and raw materials
  *It regulates flow of surface mineral, is the biological habitat for plant and animals, buffers chemical pollutants, the physical space industry and recreation.

• Land resources are essential for the maintenance of all terrestrial ecosystems

Forest Resources

• Forests are the dominant terrestrial ecosystem and vital for the ecological balance.

• Usefulness of Forest Resources: forest provides timber, oil, resins, gum, fuel and home to medicinal herbs.

Energy Resources

• Energy is defined by physicists as the capacity to do work.
  *Growing population energy has always been closely linked to man‘s economic growth and industrialization.

Renewable and Non-renewable Energy Sources

Conventional energy sources (non renewable)vs. Nonconventional sources of energy (renewable):

Important Energy Sources

Wind energy, solar energy, biomass energy hydropower and geothermal power are important renewable energy resources
Fossil fuel and gas (natural and compressed) are non-renewable resources

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