Hazard and Safety Management subject, chapter 1. According to M.Pharm 2nd semester syllabus of RGUHS.

1. HAZARDS AND SAFETY MANAGEMENT
CHAPTER 1 : MULTIDISCIPLINARY NATURE OF ENVIROMENTAL STUDIES
PRESENTED BY : AHMAD HOJABRIAN
M.PHARM 2ND SEMESTER
DEPARTMEN OF PHARMACEUTICAL QUALITY ASSURANCE
NARGUND COLLEGE OF PHARMACY, BANGALORE- 85
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2. CONTENT:
1. NATURAL RESOURCES
2. FOREST RESOURCES AND ASSOCIATED PROBLEMS
3. WATER RESOURCES AND ASSOCIATED PROBLEMS
4. MINERAL RESOURCES AND ASSOCIATED PROBLEMS
5. ENERGY RESOURCES AND ASSOCIATED PROBLEMS
6. LAND RESOURCES AND ASSOCIATED PROBLEMS
7. ECOSYSTEM – STRUCTURE AND FUNCTION
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3. NATURAL RESOURCES:
 A natural resource may be defined as any material given to us by nature which can be transformed in a way that
it becomes more valuable and useful.
 Any material may be called as a resource provided an appropriate technology is available to transform
that into more valuable goods.
 On the basis of continuity, the resources are classified as under:
 (1) Renewable Resources
 (2) Non-renewable Resources.
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4. 1. Renewable Resources
Resources, which can be renewed along with their exploitation, are always available for use.
Hence they are called renewable resources. For instance, forests are renewable. Likewise, solar energy and
wind energy are examples of renewable resources.
2. Non-renewable Resources
The formation of some resources like iron ore, coal, mineral oil etc. has taken several thousand years.
Once they are used in unlimited way, they cannot be easily replaced. Thus, their exploitation at large scale
will result in their fast depletion. Such resources are called non-renewable resources or exhaustible.
3. Cyclic Resources
For some resources there is no final use as they can be used continuously. For example, water used in
industry and domestic ways can be cleaned and used again for similar or other purpose. Such resources
are given the name of Cyclic Resources.
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5. Forest resources:
The term “forest ”is derived from the Latin word “foris” meaning outside. Originally ,it is uncultivated and
uninhabited village boundary consisting of natural plants, i.e., trees and grasses . It means an association of
plants , natural or cultivated, predominantly trees.
In the words of Allen and Shorpe, “Forest is a community of trees and associated organism covering a
considerable area, utilizing air, water and minerals to attain maturity and to reproduce and capable of
furnishing mankind with indispensable products and services”
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6. Forest resources: Importance of Forest Resources
1. Ecological Balance: Forests and wildlife are essential to
maintain ecological balance of an area.
2. Eco-system: Trees dominate forest ecosystem; their
species content varies in different parts of the world.
3. Economic Development: Forest contributes to the
economic development of the country by providing goods
and services to the people and industry.
4. Environment Quality: The forest enhances the quality of
environment by influencing the life supporting system.
5. Safeguard against Pollution: Forest check air pollution
and soil erosion. Thus, they exercise safety against pollution.
6. Soil Conservation: Forest save the hill-slopes from
landslides.
7. Wind Erosion: In deserts, trees reduce wind erosion by checking wind
velocity.
8. Maintains Ecological Balance: The forest check pollution of air through
increasing oxygen content of the air.
9. Attract Rainfall: By causing condensation of water vapour in clouds,
forests attract rains.
10. Control Floods: The floods are controlled because forests dry up
rainwater.
11. Linked with Cultural and Civilization: Forests are linked with our
culture and civilization.
12. Supply of Raw Material: Forest supply wood, which is used as Fuel,
Raw material for pulp, paper, newsprint, board; Timber for furniture
items; For preparing matches, sport goods etc.
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7. ASSOCIATED PROBLEMS:
 Deforestation.
 Timber extraction.
 Mining and its effects on forest.
 Dams and their effects on forests.
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8. DEFORESTATION:
Deforestation is the permanent destruction of forests in order to make the land available for other uses.
Main causes responsible for deforestation are as under:
a) Felling of trees to meet the ever-increasing demand of the cities.
b) To create room for cattle ranching. Grazing by the local cattle, goats, sheep etc. not only destroys
the vegetation but also pull out the roots of plants.
c) Meeting the growing hunger for land.
d) A major cause of deforestation has been the construction of hill roads. Road construction damages
the protective vegetation cover both above and below roads.
e) To harvest timber to create commercial items such as paper, furniture etc.
f) To create ingredients that are highly prized consumer items, such as the oil from palm trees.
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9. EFFECTS OF DEFORESTATION:
Loss of species: Seventy percent of the world’s plants and animals live in forests and are losing their
habitats due to deforestation, according to National Geographic. Loss of habitat can lead to species
extinction. It also has negative consequences for medicinal research and local populations who rely on
the animals and plants in the forests for hunting and medicine.
Soil erosion: Tree roots anchor the soil. Without trees, the soil is free to wash or blow away.
Life quality: Soil erosion can also lead to sediments entering the lakes, streams and other water sources.
This can decrease local water quality and contribute to poor health in populations in the area.
The deforestation also increases the soil erosion by many folds. The soil so washed leads to an
accentuated cycle of floods and drought.
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10. TIMBER EXTRACTION:
There has been unlimited exploitation of timber for commercial use. Due to increased industrial
demand; timber extraction has significant effect on forest and tribal people.
Logging:
 Poor logging results in degraded forest and may lead to soil erosion especially on slopes.
 New logging roads permit shifting cultivators and fuel wood gatherers to gain access to the logging
area.
 Loss of long-term forest productivity.
 Species of plants and animals may be eliminated.
 Exploitation of tribal people by contractor.
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11. MINING:
Major effects of mining operations on forest are:
 Mining from shallow deposits is done by surface mining while that from deep deposits is done by
sub-surface mining. It leads to degradation of lands and loss of top-soil. It is estimated that about
eighty thousands hectare land is under stress of mining activities in India.
 Mining leads to drying up perennial sources of water sources like spring and streams in mountainous
area.
 Mining and other associated activities remove vegetation along with underlying soil mantle, which
results in destruction of topography and landscape in the area.
 The forested area has declined at an average rate of 33% and the increase in non-forest area due to
mining activities has resulted in relatively unstable zones leading to landslides.
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12. DAMS:
The big dams and rivers valley projects have multi-purpose uses. However, these dams are also
responsible for the destruction of forests. They are responsible for loss of flora and fauna, increase of
water borne diseases, disturbance in forest ecosystems, rehabilitation and resettlement of tribal
peoples.
Big dams have been in sharp focus of various environmental groups all over the world, which is mainly
because of several ecological problems including deforestation and socio-economic problems related to
tribal or people associated with them. For building big dams, large scale devastation of forests takes
place which breaks the natural ecological balance of the region. Floods, droughts and landslides become
more prevalent in such areas. Forests are the sources of invaluable gifts of nature in the form of
biodiversity and by destroying them (particularly, the tropical rain forests), we are going to lose these
species even before knowing them. These species could be having economic or medicinal value and
deforestation results in loss of this storehouse of species which have evolved over millions of years.
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13. WATER RESOURCES:
Water is an important resource. An important use of water is for irrigation. Besides, water is also
required in large amounts for industrial and domestic consumption.
The significance of water needs no elucidation. It is as under:
 It is revealed by the history of human civilization that water supply and civilization are most
synonymous.
 Several cities and civilizations have disappeared due to water shortages originating from climatic
changes.
 Millions of people all over the world, particularly in the developing countries, are losing their lives
every year from water-borne disease.
 An understanding of water chemistry is the basis of knowledge of the multidimensional aspects of
aquatic environment chemistry, which involve the sources, composition, reactions, and transport of
the water.
 About 97% of the earth’s water supply is in the ocean, which is unfit of the remaining 3%, 2% is
locked in the polar ice-caps and only 1% is available as fresh water in rivers, lakes, streams, reservoirs
and ground water which is suitable for human consumption.
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14. SOURCES OF FRESH WATER:
 Surface water: Surface water mainly comes directly from rain or snow covers. The various surface
sources are natural lakes and ponds, rivers and streams, artificial reservoirs. Availability of surface
water decides the economy of the country. On one side surface water availability affects the
productivity, but on the other side water sources may cause floods and drought. Due to unequal
distribution, water may lead to national or international disputes.
 Ground water: About 9.86% of the total freshwater resources are in the form of ground water, and it
is about 35-50 times that of surface water supplies.
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15. WATER STRESS:
The concept of water stress is relatively simple. According to the World Business Council for Sustainable
Development, it applies to situations where there is not enough water for all uses, whether agricultural,
industrial or domestic. Defining thresholds for stress in terms of available water per capita is more
complex, however, entailing assumptions about water use and its efficiency. Nevertheless, it has been
proposed that when annual per capita renewable freshwater availability is less than 1,700 cubic meters,
countries begin to experience periodic or regular water stress. Below 1,000 cubic meters, water scarcity
begins to hamper economic development and human health and well-being.
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16. OVER-EXPLOITATION OF WATER:
Water Overuse
 Overuse in agriculture
 Overuse in residence
 Overuse in community
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17. Overutilization and pollution of surface
and groundwater:
 With the growth of human population there is an increasing need for larger amounts of water to
fulfill a variety of basic needs.
 Many agriculturists use more water than necessary to grow crops. There are many ways in which
farmers can use less water without reducing yields such as the use of drip irrigation systems.
Agriculture also pollutes surface water and underground water stores by the excessive use of
chemical fertilizers and pesticides.
 Industry tends to maximize short-term economic gains by not bothering about its liquid waste and
releasing it into streams, rivers and the sea.
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18. Global climate change:
 Changes in climate at a global level caused by increasing air pollution have now begun to affect the
climate. In some regions global warming has created unprecedented storms. In other areas, they lead
to long droughts.
 Everywhere the ‘greenhouse effect’ due to atmospheric pollution is leading to increasingly erratic
and unpredictable climatic effects. This has seriously affected regional hydrological conditions.
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19. Floods:
Floods have been a serious environmental hazard for centuries. However, the havoc raised by rivers
overflowing their banks has become progressively more damaging, as people have deforested
catchments and intensified use of river flood plains that once acted as safety valves. Wetlands in flood
plains are nature’s flood control systems into which overfilled rivers could spill and act like a temporary
sponge holding the water, and preventing fast flowing water from damaging surrounding land. Rivers
change their course during floods and tons of valuable soil is lost to the sea. As the forests are degraded,
rainwater no longer percolates slowly into the subsoil but runs off down the mountainside bearing large
amounts of topsoil. This blocks rivers temporarily but gives way as the pressure mounts allowing
enormous quantities of water to wash suddenly down into the plains below.
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20. Drought:
In most dry regions of the world the rains are unpredictable. This leads to periods when there is a
serious scarcity of water to drink, use in farms, or provide for urban and industrial use. Drought prone
areas are thus faced with irregular periods of famine.
While it is not feasible to prevent the failure of the monsoon, good environmental management can
reduce its ill effects. The scarcity of water during drought years affects homes, agriculture and industry. It
also leads to food shortages and malnutrition which especially affects children. One of the factors that
worsens the effect of drought is deforestation. Once hill slopes are detached of forest cover, the
rainwater rushes down the rivers and is lost. Forest cover permits water to be held in the area permitting
it to seep into the ground. This charges the underground stores of water in natural aquifers. This can be
used in drought years if the stores have been filled during a good monsoon. I
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21. MINERAL RESOURCES:
A mineral is a naturally occurring substance of definite chemical composition and identifiable physical
properties. An ore is a mineral or combination of minerals from which a useful substance, such as a
metal, can be extracted and used to manufacture a useful product.
Iron, aluminum, zinc, manganese and copper are important raw materials for industrial use. Important
non-metal resources include coal, salt, clay, cement and silica. Stone used for building material, such as
granite, marble, limestone, constitute another category of minerals. Minerals with special properties
that humans value for their aesthetic and ornamental value are gems such as diamonds, emeralds,
rubies. Gold, silver and platinum are used for ornaments. Minerals in the form of oil, gas and coal were
formed when ancient plants and animals were converted into underground fossil fuels.
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22. MINERAL RESOURCES:
Minerals and their ores need to be extracted from the earth’s interior so that they can be used.
This process is known as mining. Mining operations generally progress through four stages: (1)
Prospecting: Searching for minerals. (2) Exploration: Assessing the size, shape, location, and
economic value of the deposit. (3) Development: Work of preparing access to the deposit so
that the minerals can be extracted from it. (4) Exploitation: Extracting the minerals from the
mines.
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23. MINING ENVIROMENTAL PROBLEMS:
Mining operations are considered one of the main sources of environmental degradation. The
extraction of all these products from the lithosphere has a variety of side effects. Depletion of
available land due to mining, waste from industries, conversion of land to industry and
pollution of land, water and air by industrial wastes, are environmental side effects of the use
of these non-renewable resources. Public awareness of this problem is of a global nature and
government actions to stem the damage to the natural environment have led to numerous
international agreements and laws directed towards the prevention of activities and events
that may adversely affect the environment.
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24. ENERGY RESOURCES :
Energy consumption of a nation is usually considered as an index of its development, because almost all
the development activities are directly or indirectly dependent upon energy. Power generation and
energy consumption are crucial to economic development as economy of any nation depends upon
availability of energy resources. There are wide disparities in per capita energy use of developed and the
developing nations. With increased speed of development in the developing nations energy needs are
also increasing.
The very original form of energy technology probably was the fire, which produced heat and the early
man used it for cooking and heating purposes.
Wind and hydropower has also been used. Invention of steam engineers replaced the burning of wood
by coal and coal was further replaced by oil.
The oil producing has started twisting arms of the developed as well as developing countries by dictating
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25. ENERGY RESOURCES:
Energy resources are primarily divided into two categories viz. renewable and non-renewable sources.
Renewable energy resources must be preferred over the non-renewable resources.
It is inevitable truth that now there is an urgent need of thinking in terms of alternative sources of
energy, which are also termed as non-conventional energy sources which include:
 Solar energy needs equipment such as solar heat collectors, solar cells, solar cooker, solar water
heater, solar furnace and solar power plants .
 Wind energy
 Hydropower, Tidal energy, ocean thermal energy, geothermal energy, biomass, biogas, biofuels etc.
The non renewable energy sources include coal, petroleum, natural gas, nuclear energy.
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26. ENERGY RESOURCES
Energy resources are primarily divided into two categories viz. renewable and non-renewable sources.
Renewable energy resources must be preferred over the non-renewable resources.
It is inevitable truth that now there is an urgent need of thinking in terms of alternative sources of
energy, which are also termed as non-conventional energy sources which include:
 Solar energy needs equipment such as solar heat collectors, solar cells, solar cooker, solar water
heater, solar furnace and solar power plants .
 Wind energy
 Hydropower, Tidal energy, ocean thermal energy, geothermal energy, biomass, biogas, biofuels etc.
The non renewable energy sources include coal, petroleum, natural gas, nuclear energy.
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27. GROWING ENERGY NEEDS:
Between 1950 and 1990, the world’s energy needs increased four fold. The world’s demand for
electricity has doubled over the last 22 years! The world’s total primary energy consumption in 2000 was
9096 million tons of oil. Electricity is at present the fastest growing form of end-use energy worldwide.
For almost 200 years, coal was the primary energy source fueling the industrial revolution in the 19th
century. At the close of the 20th century, oil accounted for 39% of the world’s commercial energy
consumption, followed by coal (24%) and natural gas (24%), while nuclear (7%) and hydro/renewables
(6%) accounted for the rest.
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28. OIL AND COAL ENVIROMENTAL IMPACTS:
Oil powered vehicles emit carbon dioxide, sulphur dioxide, nitrous oxide, carbon monoxide and
particulate matter which is a major cause of air pollution especially in cities with heavy traffic density.
Leaded petrol, leads to neuro damage and reduces attention spans.
Coal and its environmental impacts: Coal is the world’s single largest contributor of green house gases
and is one of the most important causes of global warming.
Burning coal also produces oxides of Sulphur and nitrogen which, combined with water vapour, lead to
‘acid rain’. This kills forest vegetation, and damages architectural heritage sites, pollutes water and
affects human health.
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29. LAND RESOURCES:
Land area constitutes about 1/5th of the earth surface. To meet out the challenging demand of food,
fiber and fuel for human population, food for animals and industrial raw material for industries, efficient
management of land resources will play critical role. Soil, water, vegetation and climate are basic natural
resources for agricultural growth and development. If land is utilized carefully it can be considered a
renewable resource.
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30. Land Degradation:
Farmland is under threat due to more and more intense utilization. Every year, between 5 to 7 million
hectares of land worldwide is added to the existing degraded farmland. When soil is used more
intensively by farming, it is eroded more rapidly by wind and rain. Over irrigating farmland leads to
salinization, as evaporation of water brings the salts to the surface of the soil on which crops cannot
grow. Over irrigation also creates water logging of the topsoil so that crop roots are affected and the
crop deteriorates. The use of more and more chemical fertilizers poisons the soil so that eventually the
land becomes unproductive. As urban centers grow and industrial expansion occurs, the agricultural land
and forests shrink. This is a serious loss and has long term ill effects.
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31. SOIL EROSION:
The characteristics of natural ecosystems such as forests and grasslands depend on the type of soil. Soils
of various types support a wide variety of crops. The misuse of an ecosystem leads to loss of valuable soil
through erosion by the monsoon rains and, to a smaller extent, by wind. The roots of the trees in the
forest hold the soil. Deforestation thus leads to rapid soil erosion. Soil is washed into streams and is
transported into rivers and finally lost to the sea. These areas are called ‘ecologically sensitive areas’ or
ESAs.
To prevent the loss of millions of tons of valuable soil every year, it is essential to preserve what remains
of natural forest cover. It is equally important to reforest denuded areas.
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32. Desertification:
Desertification is a process whereby the productive potential of dry or semidry lands falls by ten percent
or more. Desertification is characterized by de-vegetation and depletion of groundwater, salinization and
severe soil erosion.
Salinization refers to accumulation of soluble salts in the soil. Concentration of soluble salts increases
due to poor drainage facilities. In dry land areas, salt concentration increases where poor drainage is
accompanied by high temperature. High concentration of salts affects the process of water absorption
hence affects the productivity.
Causes of desertification are, i) Deforestation ii) Overgrazing iii) Mining and quarrying
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33. Man Induced Landslides:
Human race has exploited land resources for his own comfort by constructing roads, railway tracks,
canals for irrigation, hydroelectric projects, large dams and reservoirs and mining in hilly areas.
Moreover productive lands under crop production are decreasing because of development activities.
These factors are affecting the stability of hill slopes and damage the protective vegetation cover. These
activities are also responsible to upset the balance of nature and making such areas prone to landslides.
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34. ECOSYSTEM:
The term ecosystem is defined as the system resulting from the integration of all the living and non-living
factors of the environment. The term eco refers the environment, and system implies an interacting and
interdependent complex. The organisms of any community besides interacting among themselves
always have functional relationship with the environment. This structural and functional system of
communities and environment is called ecological system or ecosystem. It is the basic functional unit in
ecology, since it includes both biotic and abiotic environment, influencing each other for maintenance of
life.
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35. CHARACTERISTICS OF ECOSYSTEM:
According to Smith (1966), the ecosystem has the following general characteristics:
 It is a major structural and functional unit of ecology.
 Its structure is related to its species diversity; the more complex ecosystems have high species diversity.
 Its function is related to energy flow and material cycling through and within the system.
 The relative amount of energy needed to maintain an ecosystem depends on its structure. The more complex
the structure, the lesser the energy it needs to maintain itself.
 It matures by passing from fewer complexes to more complex states. Early stages of each succession have an
excess of potential energy and a relatively high energy flow per unit biomass.
 Both the environment and the energy fixation in any given ecosystem are limited and cannot be exceeded
without causing serious undesirable effects.
 Alternations in the environment represent selective pressures upon the population to which it must adjust.
Organisms which are unable to adjust to the changed environment must necessarily vanish.
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36. ECOSYSTEM STRUCTURE: 36

37. ECOSYSTEM STRUCTURE:
The structure of an ecosystem is characterized by the organization of both biotic and abiotic
components. This includes the distribution of energy in our environment. It also includes the climatic
conditions prevailing in that particular environment.
The structure of an ecosystem can be split into two main components, namely:
 Biotic Components
 Abiotic Components
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38. BIOTIC COMPONENTS:
This comprises of all the living organisms. On the nourishment standpoint, they may be divided into two
categories:
 The autotrophs (autotrophic = self nourishing):
These are green plants and certain photosynthetic or chemosynthetic bacteria which can convert the light
energy of sun into potential chemical energy in the form of organic compounds needed by plants for their own
growth and development. Oxygen is produced as a by-product of photosynthesis, needed by all living organisms
for respiration. These green plants are also known as producers because they produce food for all the other
organisms.
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39. BIOTIC COMPONENTS:
 The heterotrophs (heterotrophic = other nourishing)
They are dependent directly or indirectly upon the autotrophs for their food. The organisms involved are
also known as consumers because they consume the materials built up by producers. These may be
subdivided into two kinds:
 Macroconsumers: These are organisms which ingest food and digest it inside their bodies. They may
be herbivores, carnivores, or omnivores. The herbivores are primary consumers. For example, insects
like grass hopers, chew up stems and leaves, animals like goat, cow, deer and rabbit eat up entire
aerial portion of green plants, and man eats up plant products, are all primary consumers. Frog, a
carnivore, is a secondary consumer as it eats the herbivores, the snake that eats the frog is a tertiary
consumer, there is also a class of top consumers, which are not killed and eaten by any other animals
e.g. lion, tiger, leopard, vulture, etc.
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40. BIOTIC COMPONENTS:
 Microconsumers: These are the organisms which secrete digestive enzymes to breakdown food into
simpler substances and then absorb the digested food. They are mostly parasitic and saprophytic
bacteria, actinomycetes and fungi. They are also known as decomposers because of their role in
decomposition of dead organic matter. However, the parasites are not decomposers and also some
consumers (e.g. insects and such small animals) also which help in decomposition by breaking down
the organisms into small bits. Decomposers breakdown the complex compounds of dead or living
protoplasm, absorb some of the decomposition products and release inorganic nutrients which are
cycled back to the soil and the atmosphere from where they are once again made available to the
primary producers.
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41. ABIOTIC COMPONENTS:
Structurally abiotic components include -
Climate regime: Precipitation, temperature, light, and other physical factors.
Inorganic substances: Elements such as C, N, H, O, P, S, etc., involved in material cycles.
Organic Compounds: Carbohydrates, proteins, lipids and humic substances that link the abiotic
components with the biotic components.
The minerals and atmospheric gases keep on cycling. They enter into biotic systems and after the death
and decay of organisms return to the soil and atmosphere. This is known as biogeochemical cycle. This
circulation of materials involves trapping of the solar energy by the green plants which are ultimately lost
by the organisms in several ways. The amount of abiotic materials present in an ecosystem is called
standing stage.
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42. FUNCTION OF ECOSYSTEM:
The components of the ecosystem are seen to function as a unit when we consider the following
aspects:
 Productivity
 Decomposition
 Energy flow
 Nutrient cycling
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43. FUNCTION OF ECOSYSTEM:
 Productivity: The productivity of an ecosystem is the rate at which solar energy is fixed by the
vegetation of the ecosystem; it is further classified into,
Primary productivity- It is associated with the autotrophs, most of which are photosynthetic. Thus, they
are to a much lesser extent the chemosynthetic micro organisms. These are the green plants, higher
saprophytes as well as lower forms, the phytoplankton and some photosynthetic bacteria. We can define
Primary productivity as “the rate at which radiant energy is stored by photosynthetic and chemosynthetic
activity of producers.”
Secondary productivity- These are the rates of energy storage at consumers.
level.
Net productivity- Net productivity refers to the rate of storage of organic matter not
used by the heterotrophs.
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44. FUNCTION OF ECOSYSTEM:
 Decomposition: The breakdown of complex organic matter into inorganic substances like carbon
dioxides, water and nutrients is called decomposition. Steps in decomposition :
o Fragmentation
o Leaching
o Catabolism
o Humification
o Mineralization
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45. FUNCTION OF ECOSYSTEM:
 Energy flow : The flow of energy is a one-way direction from producer to consumers, and ends in
decomposition process. It is seen that in the various biotic components of the ecosystem the energy
flow is the main driving force of nutrient circulation. The organic and inorganic substances are moved
reversibly through various closed systems in the biosphere, atmosphere, hydrosphere and
lithosphere. This activity is done in such a way that total mass of these substances remains almost the
same and is always available to biotic communities.
 Nutrient cycle : A nutrient cycle is the movement and exchange of organic and inorganic matter back
into the production of living matter.
-The process is regulated by food web pathways that decompose matter into mineral nutrients.
-Nutrient cycles occur within ecosystems
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