Components of an Ecosystem(Organisation or Structural aspect of an ecosystem)

An ecosystem comprises of two basic components

i) Abiotic components and

ii) Biotic components

The relationship between the biotic components and abiotic components of an ecosystem is called 'holocoenosis'.

Sub Topics

1. Abiotic Components 2. Biotic Components

 Abiotic ComponentsBack to Top

These include the non-living, physico - chemical factors such as air, water, soil and the basic elements and compounds of the environment.

Abiotic factors are broadly classified under three categories.

Climatic factors which include the climatic regime and physical factors of the environment like light, humidity, atmospheric temperature, wind, etc.

Edaphic factors which are related to the structure and composition of soil including its physical and chemical properties, like soil and its types, soil profile, minerals, organic matter, soil water, soil organisms.

Inorganic substances like water, carbon, sulphur, nitrogen, phosphorus and so on. Organic substances like proteins, lipids, carbohydrates, humic substances etc.

Biotic ComponentsBack to Top

It comprises the living part of the environment, which includes the association of a number of interrelated populations belonging to different species in a common environment.

The populations are that of animal community, plant community and microbial community.

Biotic community is distinguished into autotrophs, heterotrophs and saprotrophs.

Autotrophs (Gr: auto - self, trophos - feeder) are also called producers, convertors or transducers.

These are photosynthetic plants, generally chlorophyll bearing, which synthesize high-energy complex organic compounds (food) from inorganic raw materials with the help of sunlight, and the process is referred as photosynthesis.

Autortophs form the basis of any biotic system.

In terrestrial ecosystems, the autotrophs are mainly the rooted plants.

In aquatic ecosystems, floating plants called phytoplankton and shallow water rooted plants called macrophytes are the dominant producers.

Heterotrophs (Gr: heteros - other; trophs - feeder) are called consumers, which are generally animals feeding on other organisms.

Consumer's also referred as phagotrophs (phago - to ingest or swallow) or macroconsumers are mainly herbivores and carnivores.

Herbivores are referred as First order consumers or primary consumers, as they feed directly on plants.

For e.g., Terrestrial ecosystem consumers like cattle, deer, rabbit, grass hopper, etc.

Aquatic ecosystem consumers like protozoans, crustaceans, etc.

Carnivores are animals, which feed or prey upon other animals.

Primary carnivores or Second order consumers include the animals which feed on the herbivorous animals.

For e.g., fox, frog, predatory birds, smaller fishes, snakes, etc.

Secondary carnivores or Third order consumers include the animals, which feed on the primary carnivores.

For e.g., wolf, peacock, owl, etc.

Secondary carnivores are preyed upon by some larger carnivores.

Tertiary carnivores or Quaternary consumers include the animals, which feed on the secondary carnivores.

For e.g., lion, tiger, etc.

These are not eaten by any other animals.

The larger carnivores, which cannot be preyed upon further are called top carnivores.

Saprotrophs (Gr: sapros - rotten; trophos - feeder) are also called decomposers or reducers. They break down the complex organic compounds of dead matter (of plants and animals).

Decomposers do not ingest their food. Instead they secrete digestive enzymes into the dead and decaying plant and animal remains to digest the organic material. Enzymes act upon the complex organic compounds of the dead matter.

Decomposers absorb a part of the decomposition products for their own nourishment. The remaining substances are added as minerals to the substratum (mineralisation).

Released minerals are reused (utilised) as nutrients by the plants (producers).

Ecosystem Structure and FunctionIntroduction

     Biogeography reveals that living organisms (plants and animals) are found practically everywhere on this earth. The living components interact among themselves as well as with their physical environment like soil, air and water.

Ecosystem - Definition

     An ecosystem can be defined as 'a structural and functional unit of biosphere or segment of nature consisting of community of living beings and the physical environment, both interacting and exchanging materials between them'.

Components of an Ecosystem

     These include the non-living, physico - chemical factors such as air, water, soil and the basic elements and compounds of the environment.

Ecosystem - Structure and Function

     The characteristic structure of an ecosystem is obtained by the systematic physical organisation of the abiotic and biotic components of that particular ecosystem.

Primary and Secondary Productivity

     'The amount of organic matter or biomass produced by an individual organism, population, community or ecosystem during a given period of time is called productivity'.

Ten Percent Law

     Lindemann (1942) put forth ten percent law for the transfer of energy from one trophic level to the next.

Energy Flow

     Energy is the capacity to do work. Solar energy is transformed into chemical energy by the process of photosynthesis, and is stored in plant tissue and then transformed into mechanical and heat forms during metabolic activities.

Laws Governing Energy Transformations

     The storage and expenditure of energy in an ecosystem is in accordance with the laws of thermodynamics (basic laws of thermodynamics).

Food Chain and Food Webs

     Food chain is a series of groups of organisms called trophic levels, in which, there is repeated eating and eaten by so as to transfer food energy.

Characteristics of a Food Chain

     There is repeated eating in which each group eats the smaller one and is eaten by the larger one. Thus, it involves a nutritive interaction between the biotic components of an ecosystem.

Types of Food Chains

     Grazing food chain is generally seen in ecosystems such as grassland, pond or lake where a substantial part of the net primary production is grazed on by herbivores (cattle and rodents). Usually upto 50% of the NPP is grazed on by these animals in their respective ecosystems and the remaining 50% goes to the decomposer organisms as dead organic matter. Thus, in these ecosystems, the food chain is herbivore based.

Characteristics of Grazing Food Chain

     These are directly dependent upon solar radiations as the primary source of energy and the producers (green plants) synthesize their plant biomass by the process of photosynthesis. Producers form the first trophic level.

Characteristics of Detritus Food Chain

     Primary source of energy is dead organic matter called 'detritus' which are fallen leaves, plant parts or dead animal bodies.

Significance of Food Chains

     Understanding the feeding relationships and the interaction between organisms in any ecosystem.

Biological Magnification

     Certain harmful substances, usually ones not found in nature but introduced by man, may get into plants and/or animals. These poisonous substances may not be broken down in the body or excreted easily, efficiently and quickly. Instead, they accumulate in the tissues, and as

the living organism eats more, the concentration of these substances increases and they pass from one trophic level to the next.

Food Web

     In nature, food chain relationships are not isolated. They are very complex, as one organism may form the food source of many organisms. Thus, instead of a simple linear food chain, there is a web like structure formed by these interlinked food chains. Such interconnected matrix of food chains is called 'food web'.

Pyramid of Numbers

     Pyramid of numbers is the graphic representation of number of individuals per unit area of various trophic levels stepwise with producers forming the base and top carnivores the tip.

Pyramid of Biomass

     Pyramid of biomass is the graphic representation of biomass present per unit area of different trophic levels, with producers at the base and top carnivores at the tip.

Pyramid of Energy

     Pyramid of energy is a graphic representation of the amount of energy trapped per unit time and area in different trophic level of a food chain with producers forming the base and the top carnivores at the tip.

Biogeochemical Cycles

     Earth is the source of matter for all living organisms, as they require several (about 40) elements for their growth and life processes.

Types of Biogeochemical Cycles

     In gaseous cycles, the elements have a main reservoir in the gaseous phase, and the reservoir pool is the atmosphere or water. The biogenetic materials involved in circulation pass through a gaseous phase before completing the cycle.

Carbon Cycle

     Carbon is found as graphite and diamond in nature. It also occurs as carbon dioxide in the atmosphere.

Nitrogen Cycle

     Nitrogen is an important structural component of many necessary compounds, particularly proteins. Atmosphere is the reservoir of free gaseous nitrogen and nitrogen compounds are found in bodies of organisms and in the soil.

Oxygen Cycle

     Oxygen is another essential element for living organisms. It is present in large quantities (20.95% v/v) in the atmosphere and is also seen in bound state in water and as oxides and carbonates in rocks.

Water Cycle or Hydrological Cycle

     Water is an indispensable commodity of life. Water determines the distribution, structure and function of organisms in the ecosystem.

Phosphorus Cycle

     Phosphorus is an essential nutrient to biological systems. Its requirement is mainly seen in nucleic acids, cell membrane, bones and teeth.

Sulphur Cycle

     Sulphur is an important component of most proteins, few vitamins and enzymes.

Major Ecosystems (Biomes)

     Biome is a large, regional or sub continental biosystem characterized by a major vegetation type or other distinct landscape characters such as tropical deciduous forest, tundra biome, etc.

Terrestrial Biomes

     Mainly on the basis of latitude and amount and periodicity of rainfall, terrestrial biomes are classified into several types - tundra, taiga, deciduous forests, tropical rain forests, chapparal, savannah, grassland and desert.

The Tundra Biome (Rus:Tundra - Arctic hill)

     The word 'tundra' means 'North of the timber line'. Tundra biomes lie north of timberline or 60o N latitude between the Arctic ocean and the Coniferous forests. It covers about 8 x 106 sq.km area (8 million km2) extending across North America, Europe and Asia.

The Taiga Biome

     Taiga are the 'northern coniferous forests' which are also referred as 'North Woods', very common in Siberia.

The Deciduous Forests

     Also referred as "Temperate deciduous forests" are found in temperate regions of North central Europe, Eastern Asia and Eastern United States. In southern hemisphere in Australia and New Zealand.

The Chaparral Biome

     Also referred as 'Mediterranean scrub forest' extends along mediterranean, pacific coast of North America, South Africa, South and Western Australia and Chile.

The Savannah Biome

     Also referred as 'tropical grasslands', primarily located in equatorial and sub - tropical regions of the globe (especially South America, Central Africa and Australia).

Forest Biomes in India

     Major forest biomes found in India are: Tropical evergreen forests / Tropical rain forests.

Tropical Rain Forests

     Tropical rain forests grow in regions with plenty of moisture and heat. They are also referred as 'evergreen forests'.

Tropical Deciduous Forests

     In India, tropical deciduous forests occur in the northern and southern parts.

Deserts

     These ecosystems are either barren or with scanty vegetation consisting of mainly thorny bushes. Deserts are classified as warm (hot) and cold (temperate) deserts.

Altitudinal Biomes

     Variations in climatic conditions are observed not only in places on different latitudes but also with altitude. The various types of biomes can also be noted with varying altitudes as seen in the slopes of high Himalayan mountains in Asia, Andes in South America and the Rockies in North America.

Summary

     The biotic and abiotic components form an interacting system called 'ecosystem'. Producers, consumers and decomposers are the various trophic levels, which are linked by their food relationship forming a 'food chain'.

EcologyEcology is derived from Greek word in which "ecos" means "home" and "logy" means "the study

of". Ecology is the study of home. It is an interdisciplinary branch that deals with the study of

biology and earth. The term ecology was coined by a German scientistErnst Haeckel in the

year 1866. It is related to biology, genetics and ethology and an understanding on the effects of

biodiversity on the ecological functioning of an area. 

Ecology explains about 

life processes, 

interaction between organisms with the environment, 

the adaptations of these organisms, 

the movements of energy and materials through the biotic communities, 

the successive developments of ecosystems and 

also the abundance and distribution of organisms and biodiversity.

 DefinitionBack to Top

Ecology is defined as the scientific study of organisms and their interactions with the

environment. 

These interactions are such in which the organisms have with each other and their biotic

environment. 

It also includes study of diversity, distribution, biomass population of organisms and also

the competitions within them and among the ecosystems. 

Ecology is the study of environmental systems and it is sometimes known as economy

of nature. 

Ecosystem is also defined as the structural and functional unit of biosphere or a part of nature which consists of bitoic and abiotic communities, both interacting and exchanging materials between them. BiodiversityBack to Top

Biodiversity is biological diversity which describes the diversity of life which comprises of every level of

biological organization from genes to ecosystems. Biodiversity deals with the variety of life and the

processes of life. This includes all the living entities, their genetic differences, their habitat

and  communities and the ecosystem in which they are present and also the evolutionary processes that

keep the system functioning, changing and adapting. 

There are many ways to represent the term biodiversity like index, measure, characteristics that represent the complex organization of biodiversity. 

An important role of biodiversity is in ecosystem services which maintain and improve quality of human life. 

For the same, biodiversity is conserved in many ways. 

Preventing extinction of species is one way to preserve biodiversity; it can be done by using and implementing methods that preserve genetic diversity, habitat of the organisms and the ability of migration of species. 

Conservation of biodiversity, its precedence and governance systems need different methods and concepts to refer the full ecosystem. 

HabitatBack to Top

Habitat of a certain species depicts the environment in which that species is said to occur and as a result the type of community it forms. 

Habitats are defined as a part in the environment of multiple dimensions that represent both the biotic and abiotic components of the environment or any component that is related to the use of the location of that organism.

Physical features like soil, temperature, moisture and light availability and living factors like food and predators make up a habitat. 

NicheBack to Top

Niche is defined as the set of living and non-living factors in which a particular species is able of live and maintain a stable population. 

Ecological niche is a basic concept in the ecology of living organisms, the ecological niche of these organism are sub-divided as fundamental niche and realized niche. 

Fundamental niche is the environmental conditions in which the species can prevail. The realized niche is a group of environmental and ecological conditions in which the species can prevail. 

Ecological niche is a term with in actual describes a relative position of a species or population in an ecosystem. 

It also includes the response of the population or species to the available resources and enemies and the effect of these species on those factors. 

The non-living, physical factor is also a part of a niche as it influences the effect of the population and how the effects by resources and its enemies.

BiomeBack to Top

Biomes are defined as areas which are similar climatically and geographically on Earth; they

are communities of plants, animals and soil flora and fauna, which are often referred to as

ecosystems. 

They are larger units of regions which are categorized according to the structure and

composition of vegetation. 

The biotic and abiotic factors are the same in some parts of the earth and are spread

over a large area composing a typical ecosystem in an area. Such ecosystems are

known as biomes. 

Many factors like structures of plant, types of leafs, spacing of plants and climate define

a biome. They are not defined by factors like genetic, taxonomic similarities like in

ecozones.  

BiosphereBack to Top

Biosphere is the sum of all ecosystems. Biosphere is the largest scale of ecological

organization. 

Biosphere includes the spheres, lithosphere, hydrosphere and the atmosphere. 

It includes all living organisms and also the dead organic matter which is produced by

the living organisms. 

Biosphere interacts between and the exchange of matter and energy with other

spheres. 

Biosphere from an ecological point of view comprises the total biodiversity on earth and

performs all forms of ecological functions like photosynthesis, respiration, nitrogen

fixation, denitrification and decomposition.  

Population Ecology

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Population ecology deals with the dynamics of populations of species and the interaction of these species with theenvironment.

It also deals with the changes over time and space of the species living together in groups. 

Population consists of the same species that live, interact and migrate through the same habitat and niche. 

Population ecology plays an important role in conservation biology especially in the development of PVA.

It also helps in predicting long-term probability of species present in a given habitat. 

Ecosystem EcologyBack to Top

Ecosystem ecology is the study which integrates the concepts of biotic and abiotic components of ecosystem and their interaction within an ecosystem framework. 

Ecosystem ecology deals with the physical and biological factors and the interaction of the ecosystem characteristics with each other. 

In an ecosystem, organism are linked to the abiotic and biotic components of their environment to which they are adapted. 

Ecosystems are complex systems, are adaptive and have interactions of life processes. Ecosystem are broadly classified as terrestrial, freshwater, marine, or atmospheric. 

Food WebBack to Top

Food web is an ecological network, which depicts the connections of feeding in a community. 

Solar energy is used by plants to synthesize sugars during the process of

photosynthesis. 

The plants are consumed by herbivorous animals, and the energy id transferred through

a chain of organisms. 

Linear food pathways are known as food chains. 

Interconnected food chains in a community of the ecosystem creates a food web. 

Life forms are broadly classified based on their feeding practices into trophic levels as

autotroph and heterotrophs. 

Food webs consist of subgroups in a community which are linked by strong and weak

interactions between the subgroups. Interactions like this increase the stability of the

food webs. 

Trophic Level

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Trophic level of an organism is the position of that organism in a food chain. A food chain represent the organism that prey on others organisms which in turn are preyed upon by organisms of higher trophic level. Biodiversity in an ecosystem can be organized into trophic pyramids. In a trophic pyramid the vertical dimension represents feeding relations, which are consumed from the base of the food chain up to the top predators and the horizontal dimension represents the abundance at each level. Species of an ecosystem community are categorized as autotrophs, heterotrophs and detritivores. 

Autotrophs are organisms that produce their own food by the process of photosynthesis. Heteritrophs are consumers which feed on the the producers for nourishment.  Detritivores or decomposers are organisms that feed on the dead matter and convert the

matter in the basic organic compounds.

Human EcologyBack to Top

Human ecology is an interdisciplinary branch which deals with the investigation or study of ecology of our species. It deals with the study of the relationship of between humans and their natural, built and social environments. It deals with the study of relationship between humans and the natural environments and the built environment. 

Pyramid CalculatorTop

Pyramid Calculator is used to area of base, surface area and volume for triangular and square

pyramid.

Triangular pyramid is one type of three dimensional figure. It has a four vertices. Three vertices

are at the base of pyramid and another vertex is on top. Vertices are nothing, its a corner points

of the pyramid.

Square pyramid is one type of three dimensional figure. Depending upon the base shape of

pyramid, the name of the pyramid will be varied. For example, if the base of the pyramid is a

square shape, that pyramid is know as square pyramid.

 

Step by Step Calculation

Back to Top

Step 1 :  

Square Pyramid Formula:

Area of Square Base = s2

Surface Area of Square Pyramid = s2 + 2sl

Volume of Square Pyramid = 13 b2h

Where,

s (b) = side length

l = slant height

 

h = height

 

Triangular Pyramid Formula:

 

Area of Triangular Base = 12 as

 

Surface Area of Triangular Pyramid = 12as + 32 sl

 

Volume of Triangular Pyramid = 16 abh

 

Where,

 

a = apothem

 

s = side length

 

l = slant height

 

h = height

Step 2 :  

Put the values in the formula and calculate it further.

Example ProblemsBack to Top

1. Square pyramid is having side length 5 cm, height 7 cm and slant height 6 cm. Find the area of base, volume and surface area of square pyramid.

Step 1 :  

Given:

 

s = 5 cm

 

h = 7 cm

 

l = 6 cm

 

Square Pyramid Formula:

 

Area of Base = s2

 

Surface Area of Square Pyramid = s2 + 2sl

 

Volume of Square Pyramid = 13 b2h

Step 2 :  

Put the values in the formula and calculate it further.

 

Area of Square Base = 52 cm

 

                   = 25 cm2

 

Surface Area of Square Pyramid = 52 + 2 * 5 * 6

 

                                             = 25 + 60

 

                                              = 85 cm2

 

Volume of Square Pyramid = 13 52 * 7

 

                                      = 58.33 cm3

Answer  :  

Area of Square Base = 25 cm2

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Surface Area of Square Pyramid = 85 cm2

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Volume of Square Pyramid = 58.333 cm3

2. Triangular Pyramid has height 8 cm, slant height 6 cm, apothem 7 cm and side length is 5 cm. Calculate Area of base, surface area and volume of triangular pyramid.

Step 1 :  

Given:

 

s = 5 cm

 

l = 6 cm

 

a = 7 cm

 

h = 8 cm

 

Triangular Pyramid Formula:

 

Area of Triangular Base = 12 as

 

Surface Area of Triangular Pyramid = 12as + 32 sl

 

Volume of Triangular Pyramid = 16 abh

Step 2 :  

Put the values in the formula and calculate it further.

 

Area of Triangular Base = 12 * 5 * 7

 

                   = 17.5 cm2

 

Surface Area of Triangular Pyramid = 12 * 5 * 7 + 32 * 5 * 6

 

                                                  = 62.5 cm2

 

Volume of Triangular Pyramid = 16 * 7 * 6 * 8

 

                                          = 56 cm3

Answer  :  

Area of Triangular Base = 17.5 cm2

 

 

 

Surface Area of Triangular Pyramid = 62.5 cm2

 

 

 

Volume of Triangular Pyramid = 56 cm3

Ecological nicheIn ecology, a niche is a term describing the relational position of a species or population in an ecosystem.More formally, the niche includes how a population responds to the abundance of its resources and enemies (e. g., by growing when resources are abundant, and predators, parasites and pathogens are scarce) and how it affects those same factors (e. g., by reducing the abundance of resources through consumption and contributing to the population growth of enemies by falling prey to them).The abiotic or physical environment is also part of the niche because it influences how populations affect, and are affected by, resources and enemies.The description of a niche may include descriptions of the organism's life history, habitat, and place in the food chain.According to the competitive exclusion principle, no two species can occupy the same niche in the same environment for a long time.