full final eco system
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Ecosystem
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'.
Ecosystems are dynamic entities composed of the biological community and the abiotic
environment. An ecosystem's a biotic and biotic composition and structure is determined by the
state of a number of interrelated environmental factors. Changes in any of these factors will
result in dynamic changes to the nature of these systems. For example, a fire in the temperate
deciduous forest completely changes the structure of that system. There are no longer any large
trees, most of the mosses, herbs, and shrubs that occupy the forest floor are gone, and the
nutrients that were stored in the biomass are quickly released into the soil, atmosphere and
hydrologic system. After a short time of recovery, the community that was once large mature
trees now becomes a community of grasses, herbaceous species, and tree seedlings.
An ecosystem includes all of the living things (plants, animals and organisms) in a given area,
interacting with each other, and also with their non-living environments (weather, earth, sun,
soil, climate, atmosphere).
In an ecosystem, each organism has its' own niche, or role to play.
Consider a small puddle at the back of your home. In it, you may find all sorts of living things,
from microorganisms, to insects and plants. These may depend on non-living things like water,
sunlight, turbulence in the puddle, temperature, atmospheric pressure and even nutrients in the
water for life.
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This very complex, wonderful interaction of living things and their environment, has been the
foundations of energy flow and recycle of carbon and nitrogen.
Anytime a stranger (living thing(s) or external factor such as rise in temperature) is introduced
to an ecosystem, it can be disastrous to that ecosystem. This is because the new organism (or
factor) can distort the natural balance of the interaction and potentially harm or destroy the
ecosystem.
Usually, biotic members of an ecosystem, together with their abiotics factors depend on each
other. This means the absence of one member, or one abiotic factor can affect all parties of the
ecosystem.
Unfortunately ecosystems have been disrupted, and even destroyed by natural disasters such as
fires, floods, storms and volcanic eruptions. Human activities have also contributed to the
disturbance of many ecosystems andbiomes.
Biodiversity affects ecosystem function, as do the processes ofdisturbance andsuccession.
Ecosystems provide a variety ofgoods and services upon which people depend; the principles of
ecosystem management suggest that rather than managing individual species,natural resources
should be managed at the level of the ecosystem itself. Classifying ecosystems into ecologically
http://eschooltoday.com/ecosystems/what-is-a-biome.htmlhttp://en.wikipedia.org/wiki/Biodiversityhttp://en.wikipedia.org/wiki/Disturbance_(ecology)http://en.wikipedia.org/wiki/Ecological_successionhttp://en.wikipedia.org/wiki/Ecosystem_serviceshttp://en.wikipedia.org/wiki/Ecosystem_managementhttp://en.wikipedia.org/wiki/Natural_resourcehttp://en.wikipedia.org/wiki/Natural_resourcehttp://en.wikipedia.org/wiki/Ecosystem_managementhttp://en.wikipedia.org/wiki/Ecosystem_serviceshttp://en.wikipedia.org/wiki/Ecological_successionhttp://en.wikipedia.org/wiki/Disturbance_(ecology)http://en.wikipedia.org/wiki/Biodiversityhttp://eschooltoday.com/ecosystems/what-is-a-biome.html -
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homogeneous units is an important step towards effective ecosystem management, but there is no
single, agreed-upon way to do this.
Ecosystem & Function
The study of the interaction between organisms and their environment is called ecology and
the complex system of interaction between organisms and physical environment in any unit of
area is known as ecosystem.
The key feature of an ecosystem are the cycling of matter and flow of energy between various
components.
The ecosystem is made up of two main components. Biotic components which represent plants,
animals and micro-organisms and abiotic or physical components which consist of atmospheric
component, lithospheric component and hydrospheric component.
Function:
An ecosystem functions through energy transmission within its components (sourcesolar
radiation). The transfer takes place in a series of steps. Plants use light energy to convert carbon
dioxide and water to produce carbohydrates and other biochemical molecules which support life
and the process is known as photosynthesis.
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Food Chain:
The transfer of energy that takes place in a series of steps or levels is referred to as a food chain.
All organisms, including man need food which provides energy for growth, maintenance and
reproduction. Each group of organism occupies a tropic level.
Plants and other producers occupy the first level known as primary consumers. Herbivores which
feed on plants occupy the second tropic level and Carnivores that eat herbivores are at third
tropic level. The tropic level is represented in the form of a pyramid called ecological pyramid.
The energy is transferred continuously from lower to higher level. This pyramid shows that
availability of energy decreases with successive higher tropic levels.
Energy is dissipated to the environment in the form of heat and respiration. 10 to 50 per cent of
stored energy level is transferred and a perfect harmony is achieved between the cycles and the
inflow of energy establishes a dynamic and fluctuating equilibrium in the ecosystem. This is
known as ecological balance.
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History and development
The term "ecosystem" was first used in a publication by British ecologyArthur Tansley.Tansley
devised the concept to draw attention to the importance of transfers of materials between
organisms and their environment. He later refined the term, describing it as "The whole system,
... including not only the organism-complex, but also the whole complex of physical factors
forming what we call the environment". Tansley regarded ecosystems not simply as natural units,
but as mental isolates. Tansley later defined the spatial extent of ecosystems using the term
ecotope.
G. Evelyn Hutchinson,a pioneeringlimnologist who was a contemporary of Tansley's, combined
Charles Elton's ideas abouttrophic ecology with those of Russian geochemistVladimir
Vernadsky to suggest that mineral nutrient availability in a lake limited algalproduction which
would, in turn, limit the abundance of animals that feed on algae.Raymond Lindeman took these
ideas one step further to suggest that the flow of energy through a lake was the primary driver of
the ecosystem. Hutchinson's students, brothersHoward T. Odum andEugene P. Odum,further
developed a "systems approach" to the study of ecosystems, allowing them to study the flow of
energy and material through ecological systems.
Examples of ecosystems
agro-ecosystems
Agroecosystem
Aquatic ecosystem
Chaparral
Coral reef
Desert
Forest
Greater Yellowstone Ecosystem
Human ecosystem
http://en.wikipedia.org/wiki/Arthur_Tansleyhttp://en.wikipedia.org/wiki/Ecotopehttp://en.wikipedia.org/wiki/G._Evelyn_Hutchinsonhttp://en.wikipedia.org/wiki/Limnologisthttp://en.wikipedia.org/wiki/Charles_Sutherland_Eltonhttp://en.wiktionary.org/wiki/Special:Search/trophichttp://en.wikipedia.org/wiki/Vladimir_Vernadskyhttp://en.wikipedia.org/wiki/Vladimir_Vernadskyhttp://en.wikipedia.org/wiki/Primary_productionhttp://en.wikipedia.org/wiki/Raymond_Lindemanhttp://en.wikipedia.org/wiki/Howard_T._Odumhttp://en.wikipedia.org/wiki/Eugene_P._Odumhttp://en.wikipedia.org/wiki/Eugene_P._Odumhttp://en.wikipedia.org/wiki/Howard_T._Odumhttp://en.wikipedia.org/wiki/Raymond_Lindemanhttp://en.wikipedia.org/wiki/Primary_productionhttp://en.wikipedia.org/wiki/Vladimir_Vernadskyhttp://en.wikipedia.org/wiki/Vladimir_Vernadskyhttp://en.wiktionary.org/wiki/Special:Search/trophichttp://en.wikipedia.org/wiki/Charles_Sutherland_Eltonhttp://en.wikipedia.org/wiki/Limnologisthttp://en.wikipedia.org/wiki/G._Evelyn_Hutchinsonhttp://en.wikipedia.org/wiki/Ecotopehttp://en.wikipedia.org/wiki/Arthur_Tansley -
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Large marine ecosystem
Littoral zone
Lotic
Marine ecosystem
Pond Ecosystem
Prairie
Rainforest
Riparian zone
Savanna
Steppe
Subsurface Lithoautotrophic Microbial Ecosystem
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Classification of Ecosystem:
An ecosystem can be classified as below
There are further classifications in the above chart, but for a beginner level, it is enough to
concentrate on these areas. Also the study of artificial ecosystem is not the scope of an
environmental scientist. The environmentalists deal with natural creations and management only.
Moreover the system in artificial ecosystem does not offer much to study. Therefore we are more
interested in natural ecosystem and dont consider artificial ecosystem
Approach to Ecosystem:
With an ecosystem comprising of large number of species, it would seem and is impractical to
study the interaction of each organism with another, it is impossible to approach an ecosystemby studying the individual organism environment relationship. Therefore we study an
ecosystem following a wholesome approach.
ECOSYSTEM
NATURAL ECOSYSTEM ARTIFICIAL ECOSYSTEM
TERRESTRIAL
ECOSYSTEM
Forests
Grasslands
Deserts
AQUATIC
ECOSYSTEM
Fresh Waters
Marine Waters
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We study the ecosystems by studying the two aspects (attributes) of an ecosystem. They are
Structure or Architectural Process
Function or Working Process
Both processes help to understand the concept of ecosystem in simplified manner.
The architectural process classifies ecosystem into biotic and abiotic components while the
working process help to understand the interaction of ecosystem components at different levels.
Let us understand more about these approaches to understand Ecosystem.
STRUCTURE OF AN ECOSYSTEM
By Architecture or Structure of an Ecosystem, we mean
The composition of biological community including species, numbers, biomass, life
history and distribution in space, etc.
The quantity and distribution of non living materials like nutrients, water etc.
The conditions of existence such as temperature, light etc.
An ecosystem possesses both living components and biotic factors and nonliving or abiotic
factors.
The nonliving factors, called abiotic factors, are physical and chemical characteristics of the
environment. They include solar energy (amount of sun light), oxygen, CO2, water, temperature,
humidity, ph, and availability of nitrogen.
The living components of the environment are called Biotic Factors. They include all the Living
Things that affect an organism. Biotic Components are often categorized as Producers,
Consumers, and Decomposer.
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The structure of an ecosystem can be represented as below:
Scales of Ecosystems
Ecosystems come in indefinite sizes. It can exist in a small area such as underneath a rock, a
decaying tree-trunk, or a pond in your village, or it can exist in large forms such as an entire rain
forest. Technically, the Earth can be called a huge ecosystem.
The il lustration above shows an example of a small (decaying tree trunk) ecosystem
ECOSYSTEM
ABIOTIC COMPONENTS BIOTIC COMPONENTS
CLIMATIC
FACTORS
E.g. Rain
LightWind
Temp.
EDAPHIC
FACTORS
E.g. Soil
MineralsOxygen
Topography
PRODUCERS
also known as
autotrophs,
they produce
energy
CONSUMERS
also known as
heterotrophs,
they consume
and transfer
energy
DECOMPOSERS
better known as
reducers or
saptrotrophs
recycle energy
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To make things simple, let us classify ecosystems into three main scales.
Micro:
A small scale ecosystem such as a pond, puddle, tree trunk, under a rock etc.
Messo:
A medium scale ecosystem such as a forest or a large lake.
Biome:
A very large ecosystem or collection of ecosystems with similar biotic and abiotic factors such asan entire Rain forest with millions of animals and trees, with many different water bodies
running through them.
Ecosystem boundaries are not marked (separated) by rigid lines.
They are often separated by geographical barriers such as deserts, mountains, oceans, lakes and
rivers. As these borders are never rigid, ecosystems tend to blend into each other. This is why a
lake can have many small ecosystems with their own unique characteristics. Scientists call this
blending ecotone
Ecosystems can be put into 2 groups. If the ecosystem exists in a water body, like an ocean,
freshwater or puddle, it is called an aquatic ecosystem. Those that exists outside of water bodies
are called terrestrial ecosystems.
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Levels of organization in an ecosystem
To understand the levels of belonging in an ecosystem, let us consider the diagram below.
Individual, Species, Organism:
An individual is any living thing or organism. Individuals do not breed with individuals from
other groups. Animals, unlike plants, tend to be very definite with this term because some plants
can cross-breed with other fertile plants.
In the diagram above, you will notice that Gill, the goldfish, is interacting with its environment,
and will only crossbreed with other gold fishes just like her.
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Population:
A group of individuals of a given species that live in a specific geographic area at a given time.
(example is Gill and his family and friends and other fishes of Gills species) Note that
populations include individuals of the same species, but may have different genetic makeup such
as hair/eye/skin colour and size between themselves and other populations.
Community:
This includes all the populations in a specific area at a given time. A community includes
populations of organisms of different species. In the diagram above, note how populations of
gold fishes, salmons, crabs and herrings coexist in a defined location. A great community usually
includes biodiversity.
Ecosystem:
As explained in the pages earlier, ecosystems include more than a community of living
organisms (abiotic) interacting with the environment (abiotic). At this level note how they
depend on other abiotic factors such as rocks, water, air and temperature.
Biome:
A biome, in simple terms, is a set of ecosystems sharing similar characteristics with their abiotic
factors adapted to their environments.
Biosphere:
When we consider all the different biomes, each blending into the other, will all humans living in
many different geographic areas, we form a huge community of humans, animals and plants, in
their defined habitats. A biosphere is the sum of all the ecosystems established on Earth.
What is a biome?
Biomes are very large ecological areas on the earths surface, with fauna and flora (animals and
plants) adapting to their environment. Biomes are often defined by abiotic factors such as
climate, relief, geology, soils and vegetation. A biomeis NOT an ecosystem, although in a way
it can look like a massive ecosystem.
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If you take a closer look, you will notice that plants or animals in any of the biomes have special
adaptations that make it possible for them to exist in that area. You may find many units of
ecosystems within one biome.
There are five major categories of biomes on earth. In these five, there are many sub-biomes,
under which are many more well defined ecosystems.
Let us take a quick look at each of these biomes below:
The Desert Biomes: They are the Hot and Dry Deserts, Semi Arid Deserts, Coastal Deserts and
Cold Deserts.
The Aquatic Biomes: Aquatic biomes are grouped into two, Freshwater Biomes (lakes and
ponds, rivers and streams, wetlands) and Marine Biomes (oceans, coral reefs and estuaries).
The Forest Biomes:There are three main biomes that make up Forest Biomes. These are the
Tropical Rainforest, Temperate and Boreal Forests (also called the Taiga)
The Grassland Biomes:There are two main types of grassland biomes: the Savanna Grasslands
and the Temperate Grasslands.
The Tundra Biomes:There are two major tundra biomesThe Artic Tundra and the Alpine
Tundra.
Biomes play a crucial role in sustaining life on earth. For example, the Aquatic biome is home to
millions of fish species and the source of the water cycle. It also plays a very important role in
climate formation. The terrestrial biomes provide foods, enrich the air with oxygen and absorb
carbon dioxide and other bad gases from the air. They also help regulate climate and so on.
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Food chains
All living things need to feed to get energy to grow, move and reproduce. But what do these
living things feed on? Smaller insects feed on green plants, and bigger animals feed on smaller
ones and so on. This feeding relationship in an ecosystem is called a food chain. Food chains are
usually in a sequence, with an arrow used to show the flow of energy.
A food chain is not the same as a food web.
A food web is a network of many food chains and is more complex.
See the food web illustration belowyou can pick out a basic food chain from the web: Green
plants Grasshopper Frog Bird Hawk
I n the diagram above, arrow shows the dir ection of energy flow. It points to the animal doing
the eating.
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Energy Flow in the Ecosystem:
Energy flows through an ecosystem and is ultimately lost to the environment. Matter, on the
other hand, is recycled. Matter is finite. If matter was not cycled through the ecosystem, the
supply would have been exhausted a long time ago. A simple matter cycle consists of an
exchange of matter between living and non-living components of an ecosystem. Organisms
incorporate various elements (compounds) from the environment into their bodies. When these
organisms die, their bodies are broken down by decomposers and the compounds are released
into the environment.
Water Cycle:
The Water Cycle
The water cycle, also called the hydrologic cycle, follows the continuous path of water. Water
enters the vapor phase through evaporation and transpiration (the release of water vapor from
plants and animals). The sun is the main source of energy that allows the water to undergo a
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phase change. The water vapor raises, cools, and condenses forming clouds. The water droplets
become heavier and eventually fall as precipitation. A small portion of the precipitation will be
taken up by the plants and animals more will infiltrate the soil, entering the water table, with the
largest portion of the precipitation forming runoff on the surface of the land to drain into streams,
rivers, lakes, and ultimately the ocean. The hydrologic cycle is a continuous process that recycles
all the water on the planet.
Trophic levels of food chains
The levels of a food chain (food pyramid) is called Trophic levels. The trophic level of an
organism is the level it holds in a food pyramid.
The sunis the source of all the energy in food chains. Green plants, usually the first level of
any food chain, absorb some of the Suns light energy to make their own food by photosynthesis.
Green plants (autotrophs) are therefore known as Producers in a foodchain.
The second level of the food chains is called the Primary Consumer. These consume the
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green plants. Animals in this group are usually herbivores. Examples include insects, sheep,
caterpillars and even cows.
The third in the chain are Secondary Consumers.These usually eat up the primary
consumers and other animal matter. They are commonly called carnivores and examples include
lions, snakes and cats.
The fourth level is called Tertiary Consumers.These are animals that eat secondary
consumers.
Quaternary Consumerseat tertiary consumers.
At the top of the levels are Predators. They are animals that have little or no natural enemies.
They are the bosses of their ecosystems. Predators feed on preys. A prey is an animal that
predators hunt to kill and feed on. Predators include owls, snakes, wild cats, crocodiles and
sharks. Humans can also be called predators.
When any organism dies, detrivores(like vultures, worms and crabs) eat them up. The rest
are broken down by decomposers (mostly bacteria and fungi), and the exchange of energy
continues. Decomposers start the cycle again.
Carbon Cycle
The carbon cycle is very important to all ecosystems, and ultimately life on earth. The carbon
cycle is critical to the food chain.
Living tissue contain carbon, because they contain proteins, fats and carbohydrates. The carbon
in these (living or dead) tissues is recycled in various processes.
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Human activities like heating homes and cars burning fuels (combustion) give off carbon into the
atmosphere. During respiration, animals also introduce carbon into the atmosphere in the form of
carbon dioxide.
The Carbon dioxide in the atmosphere is absorbed by green plants (producers) to make food in
photosynthesis.
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When animals feed on green plants, they pass on carbon compounds unto other animals in the
upper levels of their food chains. Animals give off carbon dioxide into the atmosphere during
respiration.
Carbon dioxide is also given off when plants and animals die. This occurs when decomposers
(bacteria and fungi) break down dead plants and animals (decomposition) and release the carbon
compounds stored in them.
Very often, energy trapped in the dead materials becomes fossil fuels which is used as
combustion again at a later time.
The Nitrogen Cycle
Nitrogen is also key in the existence of ecosystems and food chains. Nitrogen forms about 78%
of the air on earth. But plants do not use nitrogen directly from the air. This is because nitrogen
itself is unreactive, and cannot be used by green plants to make protein. Nitrogen gas thereforeneeds to be converted into nitrate compound in the soil by nitrogen-fixing bacteria in soil, root
nodules or lightning.
To understand the cycle better, let us consider the diagram below:
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1. Nitrogen is introduced to the soil by precipitation (rain, lightling).
2. Nitrates dont only come from Nitrogen in the air. They can also be obtained by the
conversion of ammonia, commonly used in fertilizers by nitrifying bacteria in the soil. Some root
nodules can also convert nitrogen in the soil into nitrates.
3. Plants build up proteins using nitrates absorbed from the soil.
4. When animals like cows, eat these plants, they in turn use it to build animal protein.
5-6. When these animals (cows) poop, pee or die, the urea, excreta or carcass are broken
down by decomposers and the nitrogen is re-introduced into the soil in the form of ammonia.
7. Nitrates in he soil can also be broken down by denitrifying bacteria (in specific conditions)
and sent into the air as nitrogen. This process can help make the soil infertile, because it will lack
the nitrates needed for plant use.
Once nitrogen gets back into the air, the cycle continues.
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Benefits of ecosystems
The interaction of living things depending on each other and relating to their environments has
immense benefits in terms of the health and spiritual wellbeing of humans, the health of
members of the ecosystem themselves, as well as the environment. Living things do not exist in
isolation. They depend on abiotic factors too. The benefit of ecosystems therefore is not
exclusive to living things.
A. Supportive
Ecosystems provide a supporting role for all its members. In this role, living members serve as
food for others, and their produce and residue serve as nutrients to soils and gases to the
atmosphere. This makes soil nutrient cycle, carbon and oxygen cycle and water cycle possible
and also for living things to continue procreation.
B. Provision
Ecosystems are also the source of all foods, store of all energy, fibre, genetic resources,
medicines, fresh water and minerals. All natural resources that humans depend on, has its source
from ecosystems.
C. Regulation
The function of a healthy ecosystem ensures that there is balance and regulation in the climate,
regulation in fresh water, soils, rocks, and atmosphere. They function to regulate animals and
plant diseases and ensure that biodiversity is preserved.
D. Spiritual Value
Perhaps not exclusive to humans, ecosystems provide humans with deeper spiritual enrichment
and cognitive development. The wonder and breathtaking properties of healthy ecosystems has
recreational effects, as well as aesthetic value to us. From land the remotest places on earth to the
deepest places in the oceans, there are millions of life forms that function in harmony, and
provide humans with meditative and healing benefits.
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Threats to Ecosystems
Anything that attempts to alter the balance of the ecosystem potentially threatens the health and
existence of that ecosystem. Some of these threats are not overly worrying as they may be
naturally resolved provided the natural conditions are restored. Other factors can destroy
ecosystems and render all or some of its life forms extinct. Here are a few:
Habitat Destruction
Economic activities such as logging, mining, farming and construction often involve clearing out
places with natural vegetative cover. Very often, tampering with one factor of the ecosystem can
have a ripple effect on it and affect many more or all other factors of that ecosystem. For
example, clearing a piece of forest for timber can expose the upper layers of the soil to the sun's
heat, causing erosion and drying. It can cause a lot of animals and insects that depended on the
shade and moisture from the tree to die or migrate to other places.
Pollution
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Water, land and air pollution all together play a crucial role in the health of ecosystems. Pollution
may be natural or human caused, but regardless they potentially release destructive agents or
chemicals (pollutants) into the environments of living things. In a lake, for example, it can
create havoc on the ecological balance by stimulating plant growth and causing the death of fish
due to suffocation resulting from lack of oxygen. The oxygen cycle will stop, and the polluted
water will also affect the animals dependent on the lake water Source: Study the effect of
pollution on an ecosystem, WWF.
Eutrophication
This is the enrichment of water bodies with plant biomass as a result of continuous inflow of
nutrients particularly nitrogen and phosphorus. Eutrophication of water fuels excessive plant and
algae growth and also hurts water life, often resulting in the loss of flora and fauna diversity.
The known consequences of cultural eutrophication include blooms of blue-green algae (i.e.,
cyanobacteria, Figure 2), tainted drinking water supplies, degradation of recreational
opportunities, and hypoxia. The estimated cost of damage mediated by eutrophication in the U.S.
alone is approximately $2.2 billion annually (Dodds et al. 2009) Source: Eutrophication: Causes,
Consequences, and Controls in Aquatic Ecosystems, Michael F. Chislock
Invasive species
Any foreign specie (biological) that finds its way into an ecosystem, either by natural or human
introduction can have an effect on the ecosystem. If this alien has the ability to prey on
vulnerable and native members of that ecosystem, they will be wiped out, sooner or later. One
devastating impact of introducing alien Nile Perch and Nile Tilapia into Lake Victoria in the
1970s was the extinction of almost half of the 350+ endemic species of fish in the cichlid family.
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Overharvesting
Fish species, game and special plants all do fall victim from time to time as a result of over
harvesting or humans over dependence on them. Overharvesting leads to reduction in
populations, community structures and distributions, with an overall reduction in recruitment.
Lots of fish species are know to have reached their maximum exploitation level, and others will
soon be. For example Oreochromis karongae is one of the most valuable food fishes in Malawi,
but populations collapsed in the 1990s due to overfishing, and it is now assessed as Endangered.
Source: IUCN, Major Threats
UV Radiation
The suns rays play an important role in living things. UV rays come in three main wavelengths:
UVA, UVB and UVC, and they have different properties. UVA has long wavelengths and
reaches the earths surface all the time. It helps generate vitamin D for living things. UVB and
UVC are more destructive and can cause DNA and cell damage to plans and animals. Ozone
depletion is one way that exposes living things to UVB and UVC and the harm caused can wipe
lots of species, and affect ecosystems members including humans
Preserving Ecosystems
Considering the threats facing ecosystems, we can begin to appreciate the importance of policy,
rules and regulation in human activity towards ecosystems. Here are a few ways we can ensure
the health and smooth functioning of ecosystems.
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such that when the waste water is deposited into water bodies, it is properly filtered and treated
to reduce the organic nutrient content.
Pollution
Air and land pollution together have effects on water bodies too. Acid rains and chemical runoff
all affect life forms in the water. Oils that are discharged into water bodies can have a
devastating effect. In aquatic ecosystems, air pollution acidifies surface waters, reducing their
ability to sustain native fish. In estuaries and coastal waters, it contributes to nutrient over-
enrichment, producing algal blooms, foul smells and low oxygen levels. It also causes mercury
to accumulate in aquatic food webs, threatening the health of both people and wild animals2
Ozone
Ozone is a secondary pollutant. It is the result of the formation of precursors nitrogen oxides and
Volatile Organic Compounds (VOC). Biomass burning produces this. It is known that forest
cover act as a net sink of ozone. It is therefore important that we preserve natural vegetativecovers on earth and invest in energy forms that reduce the emissions of VOCs.
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Ecological Imbalance - Imperiling the Ecosystem:
Industrialization exploiting Ecological Balance
With the increased industrialization and scientific approach to our life, the natural resources and
rich natural heritage which were being preserved for centuries have begun dwindling greatly.
Any kind of imbalance in nature results into severe danger to our ecosystem.
Its treatment with nature has posed today many serious challenges and problems like climate
change, vector-borne disease, decay in wildlife and its resources and food and water shortage.
Exploitation of natural resources prevalent all over the world has erupted into severe ecological
degradation, which is definitely the biggest threat to proper functioning of our ecosystem.
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Biodiversity & Ecosystem Conservation:
Biodiversity and Ecosystem
Biodiversity and ecosystems sustain each other. They are the living natural capital on which
human beings, as one species among others, depend for existence and well-being. Biodiversity
and ecosystems are the natural basis for the development of sustainable resource uses, including
forestry, farms, renewable energy, urban land use, fisheries and other coastal & marine uses.
Proactive programs to conserve biodiversity include research and management for wild
populations and habitats, protected areas, large ecosystems such as Great Lakes, grasslands,
forests, wetlands, deserts, major rivers and estuaries, oceans, and more sustainable resource
practices. They also include planning, monitoring and enforcement related to land, sea and
resource uses, environmental assessment, pollution and species at risk.
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The need for conservation action is urgent, nationally and globally. The last two centuries have
seen increasing rates of depletion of natural capital, with resulting changes increasingly evident
even at global levels, such as climate change, large ecosystem fragmentation and degradation,
and species extinctions. There is now a higher level of multilateral and national fora and talk for
conservation, but the negative momentum is as yet only barely affected.
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Ways to Preserve Ecosystems
Defining the Issues
Identify the problem. The first step in developing a solution is defining exactly what is affecting
an ecosystem. Soil and water testing are two ways to assess an ecosystems health. Surveys and
inventories of plants and wildlife are other tools resource managers can use. This information
allows managers to quantify the effects and provide a way to gauge the success of preservation
efforts.
Correcting Environmental Problems
Reduce nonpoint source pollution (NSP). Nonpoint source pollution occurs when precipitation
creates runoff that transports pollutants from the contamination source. NSP does not always
have a single, identifiable source. The causes of NSP can be diffuse and far from the point of
impact. Emissions from fossil-burning coal plants can drift hundreds of miles from their source.
The U.S. Environmental Protection Agency has identified agricultural runoff, one form of NSP,
as the primary source of water pollution.
Eradicate invasive and nonnative plant species. Many ecosystems are severely affected by these
species. They often invade an ecosystem where the land has been disturbed. Once they take hold,
they can crowd out native plant species, destroying the biodiversity of an ecosystem. Often, these
weed species replace food resources, affecting wildlife in the ecosystem.
Limit or restrict human activity in sensitive areas. Even the most innocuous activities, such as
walking a trail, can inadvertently introduce invasive and nonnative plant species into a pristinearea. Seeds can easily be transported on clothing or shoes. More intense activities such as
mountain biking and horseback riding can do widespread damage, leading to erosion and loss of
topsoil.
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Keep ecosystems intact. Many species rely on unbroken tracts of habitat to fulfill their basic
needs. Ecosystems evolve with the organisms that depend upon it. Managing for plants and
wildlife, therefore, makes good ecological sense. A fragmented habitat also increases an
ecosystems vulnerability to invasion of weed species by providing more area for potential
contact.
Early Detection
Continue to monitor plant and animal populations, including those in aquatic environments.
Often, the plant and animal species within an ecosystem can be indicators of the ecosystem's
health. Macro-organism and amphibians in aquatic habitats are vulnerable to changes in water
chemistry. These organisms can indicate a potential problem long before it becomes evident in
other wildlife populations or on the landscape itself.
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References
Biology Concepts & Connections Sixth Edition, Campbell, Neil A. Retrieved
1. Geosystems: An Introduction to Physical Geography. Prentice Hall Inc.
2. ^ Odum, EP Fundamentals of ecology, third edition, Saunders New York
3. ^ a b Tansley, AG "The use and abuse of vegetational terms and concepts".
4. ^ Tansley, AG The British islands and their vegetation. Cambridge University Press, United.
Kingdom.
5. ^ United Nations Environment Programme. Convention on Biological Diversity.
6. ^ Mller-Dombois & Ellenberg: "A Tentative Physiognomic-Ecological Classification of
Plant Formations of the Earth"