Full Final Eco System

8/10/2019 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"

Full Final Eco System

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