ASSIGNMENT

ASSIGNMENT

1. MANNAM FOUNDATION CENTRE FOR
EDUCATION TECHNOLOGY
PORUVAZHY, EDAKKADU, KOLLAM
2014-2015




ASSIGNMENT


Submitted to Submitted by
Rintu Chacko Saranya T S
Natural Science Natural Science
Reg. No: 18114373023

Submitted on
27-10-2015

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TOPIC

ECOSYSTEM

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INDEX

Sl No. Contents Page No.
1 Introduction 3
2 Components of Eco system 4-5
3 Conclusion 6
4 Reference 7

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INTRODUCTION


An ecosystem consists of the biological community that occurs in some
locale, and the physical and chemical factors that make up its non-living or
abiotic environment. There are many examples of ecosystems -- a pond, a
forest, an estuary, a grassland. The boundaries are not fixed in any objective
way, although sometimes they seem obvious, as with the shoreline of a small
pond. Usually the boundaries of an ecosystem are chosen for practical reasons
having to do with the goals of the particular study.
The study of ecosystems mainly consists of the study of certain processes
that link the living, or biotic, components to the non-living, or abiotic,
components. Energy transformations andbiogeochemical cycling are the main
processes that comprise the field of ecosystem ecology. As we learned earlier,
ecology generally is defined as the interactions of organisms with one another
and with the environment in which they occur. We can study ecology at the
level of the individual, the population, the community, and the ecosystem.
Studies of individuals are concerned mostly about physiology, reproduction,
development or behavior, and studies of populations usually focus on the habitat
and resource needs of individual species, their group behaviors, population
growth, and what limits their abundance or causes extinction. Studies
of communities examine how populations of many species interact with one
another, such as predators and their prey, or competitors that share common
needs or resources.
In ecosystem ecology we put all of this together and, insofar as we can,
we try to understand how the system operates as a whole. This means that,
rather than worrying mainly about particular species, we try to focus on major
functional aspects of the system.

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COMPONENTS OF AN ECOSYSTEM


1. Abiotic Substances:
These include basic inorganic and organic compounds of the environment or
habitat of the organism. The inorganic components of an ecosystem are carbon
dioxide, water, nitrogen, calcium, phosphate, all of which are involved in matter
cycles (biogeochemical cycles).
The organic components of an ecosystem are proteins, carbohydrates,
lipids and amino acids, all of which are synthesized by the biota (flora and
fauna) of an ecosystem and are reached to ecosystem as their wastes, dead
remains, etc, The climate, temperature, light, soil, etc., are other abiotic
components of the ecosystem.
2. Producers:
Producers are autotrophic organisms like chemosynthetic and photosynthetic
bacteria, blue green algae, algae and all other green plants. They are called
ecosystem producers because they capture energy from non-organic sources,
especially light, and store some of the energy the form of chemical bonds, for
the later use.
Algae of various types are the most important producers of aquatic
ecosystems, although in estuaries and marshes, grasses may be important as
producers. Terrestrial ecosystems have trees, shrubs, herbs, grasses, and mosses
that contribute with varying importance to the production of the ecosystem.
Since heterotrophic organisms depend on plants and other autotrophic
Organisms like bacteria and algae for their nutrition, the amount of energy that
the producers capture, sets the limit on the availability of energy for the
ecosystem. Thus, when a green plant captures a certain amount of energy from
sunlight, it is said to “produce” the energy for the ecosystem.

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3. Consumers:
They are heterotrophic organisms in the ecosystem which eat other living
creatures. There are herbivores, which eat plants, and carnivores, which eat
other animals. They are also called phagotrophs or macroconsumers. Sometimes
herbivores are called primary macroconsumers and carnivores are called
secondary Macroconsumers.
4. Reducers or Decomposers:
Reducers, decomposers, saprotrophs or Macroconsumers are heterotrophic
organisms that breakdown dead and waste matter. Fungi and certain bacteria are
the prime representatives of this category. Enzymes are secreted by their cells
into or onto dead plant and animal debris. These chemicals digest the dead
organism into smaller bits or molecules, which can be absorbed by the fungi or
bacteria (saprotrophs).
The decomposers take the energy and matter that they harvest during this
feeding process for their own metabolism. Heat is liberated in each chemical
conversion along the metabolic pathway.
No ecosystem could function long without decomposers. Dead organisms
would pile up without rotting, as would waste products. It would not be long
before an essential element, phosphorus, for example, would be first in short
supply and then gone altogether, because the dead corpses littering the
landscape would be hoarding the entire supply.
Thus, the importance of the decomposers to the ecosystem is that they
tear apart organisms and in their metabolic processes release to the environment
atoms and molecules that can be reused again by autotrophic organisms. They
are not important to the ecosystem from the energy point of view but from the
material (nutrient) point of view. Energy cannot be recycled, but matter can be.
Energy must be fed into ecosystem to keep up with the dissipation of heat or the
increase in entropy.

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CONCLUSION


An ecosystem is a community of living organisms in conjunction with
the nonliving components of their environment (things like air, water and
mineral soil), interacting as a system. These biotic and abiotic components are
regarded as linked together through nutrient cycles and energy flows. As
ecosystems are defined by the network of interactions among organisms, and
between organisms and their environment, they can be of any size but usually
encompass specific, limited spaces (although some scientists say that the entire
planet is an ecosystem).
Energy, water, nitrogen and soil minerals are other essential abiotic
components of an ecosystem. The energy that flows through ecosystems is
obtained primarily from the sun. It generally enters the system
through photosynthesis, a process that also captures carbon from the
atmosphere. By feeding on plants and on one another, animals play an important
role in the movement of matter and energy through the system. They also
influence the quantity of plant and microbial biomass present. By breaking
down dead organic matter, decomposers release carbon back to the atmosphere
and facilitate nutrient cycling by converting nutrients stored in dead biomass
back to a form that can be readily used by plants and other microbes

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REFERENCE
1. http://www.globalchange.umich.edu
2. http://www.yourarticlelibrary.com