Why is there a need for conservation

www.allenswcd.org/
Conservation is the protection and preservation of natural resources in the environment. There a need to conserve .

1) to prevent extinction of plant species
2) to maintain a stable and balanced ecosystem .this prevents disruption of natural cycles .
3) to maintain a large gene pool many wild plants possess favorable genes , by crossbreeding the variety , we can improve agricultural produce.
4) To ensure the conservation of marine life, as they are a source food
5) Conservation is of scientific value .studying the wildlife provides useful information to humans
6) Conservation preserves natural greenery and wildlife for people to appreciate.
7) To maintain biodiversity ,rainforest is a house of a large number of species and are o graet economic impotance.
a) tropical plants provide raw materials for industries
b) tropical plants provide raw materials for medicinal drugs and natural insecticide.
c)tropical rainforest is a source of food .

Biomagnification

Biomagnification is the bioaccumulation of a substance up the food chain by transfer of residues of the substance in smaller organisms that are food for larger organisms in the chain. It generally refers to the sequence of processes that results in higher concentrations in organisms at higher levels in the food chain (at higher trophic levels). These processes result in an organism having higher concentrations of a substance than is present in the organism’s food. http://toxics.usgs.gov/definitions/biomagnification.html
Organism which feed higher levels of DDT from consuming their prey , it is not poisonous in small amounts and eventually the DDT concentration accumulates to the extend that the top consumers suffer the effects of bioaccumulation

Eutrophication

Eutrophication is a process whereby water bodies, such as lakes, estuaries, or slow-moving streams receive excess nutrients that stimulate excessive plant growth . This enhances plant growth, , reduces dissolved oxygen in the water when dead plant material decomposes and can cause other organisms to die.

http://toxics.usgs.gov/definitions/eutrophication.html

this is the process

fertilizers not absorbed by plants are washed into near lakes, the nitrates and phosphates facilitate plant growth , this added nutrients enhance the growth of algae and water plants , the submerged algae and plants die due to insufficient sunlight, dead bodies get decomposed by bacteria , giving rise to growth of bacteria using up the oxygen in the water thus the other organisms die or are affected eventually

uncontrolled fishing practices

Over fishing occurs when the population decreases in large numbers . some of their methods destroy the seabed and marine habitat.
There are detrimental effects of uncontrolled fishing practices , the species of fish will be caught faster than they can be replaced . the young fishes that are caught are not able to reproduce causing decline in their population and those caught unintentionally would die and more species would become endangered or face extincton.

the impact of human activities on our ecosystem

http://static.howstuffworks.com/gif/deforestation-2.jpgD
deforestation

This refers to the clearing of forest . They are cleared to meet the rising demands of land and materials.
with the use of modern technology , forest are being cleared at a faster rate than it could be replaced. This often results in undesirable consequences
1) soil erosion: the canopy of trees acts as a shield to protect the soil from the rain water . rain water is stored and absorbed by the roots of trees and gradually released into the soil , with the trees gone,soil is exposed directly to the force of rain,topsoil , also the most fertile layer , gets washed away or eroded during heavy rain
2) flooding: the eroded soil might get deposited in the rivers , disrupting the flow of the river , causing a rise in water levels , causing floods .
3) desertification: exposed to sunlight , water is removed from soil causing it to harden , with the topsoil eroded , land becomes barren , plants are not able to grow and the end result is that habitats and organisms get extinct .overgrazing also leads to desertification
4) climate changes : this is caused by deforestation as when rain water is retained in roots of trees , they are lost as transpiration , and producing rain . without trees , the annual rainfall will decrease.

1) In any ecosystem, the ultimate source of energy is the sun. 2) chlorophyll in plants absorb light energy which is converted during photosynthesis.

http://eo.ucar.edu/kids/green/cycles6.htm
The carbon process is made up of processes by which carbon dioxide is removed from and restored to the environment.

Removal of carbon dioxide from the environment

During photosynthesis , green plants absorb carbon dioxide from the atmosphere and use it to manufacture carbohydrates.

The glucose may be changed to other organic compound like amino acid.

The animals feed on green plants , the carbon compounds become part of these animals OR the carbon compounds may also be preserved in fossil fuels like coal

Release of carbon dioxide into environment

carbon dioxide is release into the environment through:
1) respiration
during respiration , carbon compounds are broken down into their bodies and carbon dioxide is released into environment.
2) COMBUSTION: when fossil fuels are burnt, the carbon compounds preserved in the fossil fuels are broken down and carbon dioxide is realeased
3) Decay: when organisms die, their bodies are broken down by decomposers , carbon dioxide is released and some simple substances are absorbed by decomposers and become part of their bodies . when decomposers respire , they too give out carbon dioxide .
The carbon cycle is vital as it provides us a continuous supply of carbon dioxide for plants and allows energy to flow through the ecosystem

What happens to most of the energy in the ecosystem?

1) In any ecosystem, the ultimate source of energy is the sun.
2) chlorophyll in plants absorb light energy which is converted during photosynthesis.
3) Energy that it produce dcrease from one level to another by feeding
4) This flow of energy is non-cyclic . energy is released as heat to the environment as it flows through the ecosystem .This organism neither returns to the same system nor the organisms which produces it, therefore it cannot be recycled in the ecosystem
5) The dead organisms and excreted materials contain trapped energy. This is released by the activity of decomposers, the rest of the energy is loss as heat.

why are short food chains better?

As energy is lost at each tropic level, lesser energy is available for the organism at the next level, the the food chain . thus a shorter food chain is more efficient than a longer one as more energy is available to the final consumer as less energy is loss to the surroundings

ECOLOGICAL PYRAMIDS

http://www.envf.port.ac.uk/geog/teaching/environ/sect2-3c.htm
http://resources.edb.gov.hk/biology/english/images/environment/pyramid.gif


It allows us to compare the tropic levels in a food chain. There are three types.
Pyramids of numbers
This allows us to compare the number of organisms present in each trophic level at a particular time.

In this pyramid, all the numbers at each trophic level are counted regardless of size and stage development.
http://www.sturgeon.ab.ca/rw/Pyramids/pyrakind.htm







Pyramid of biomass

This allows us to compare the mass of organisms present in each trophic level at a particular time

The pyramid of biomass is constructed based on the dry mass of organisms in each trophic level at any one time. This is called the standing mass of organisms.
The unit of biomass is dry weight of organic matter( per square metre)

pyramid of energy

The total energy at various trophies levels of a food chain represented in a pyramid is called a pyramid of energy.

This is constructed based on total energy level in each trophic level over a certain period of time . down a food chain as energy is transferred from one trophic level to the next, energy is loss. Which is why a this pyramid is always broad at the base and narrow toward the top .


http://resources.edb.gov.hk/biology/english/images/environment/pyramid.gif

Relationship between predator and prey

http://www.tiem.utk.edu/bioed/bealsmodules/pred-prey.gph1.gif
Let me first explain the definitions.

Predator : A predator is an organism that kills and feeds on other organisms
Prey: the organisms that are eaten are called prey.

An increase in the population size would provide more food for the predator, thus the increase in predator will in turn result in a decrease in population of the prey as more predator feed on them and eventually the predator population will decrease as well, and there would be a rise in the prey population again.
This cycle repeats itself but the average size of the prey population is greater than that of the predator population.
Two predators with the same prey

The land snail is eaten by fishes and frogs

food chains and food web

Food chain− series of organisms through which energy is transferred in the form of food
grass→ chicken→ snake→ man

Foodweb
−food chains interlinked
http://www.vtaide.com/png/foodchains.htm

How do energy and nutrients flow through ecosysytem?

The organisms in an ecosystem consist of produces , consumers and decomposers . energy is passed from the producers to consumers to decomposes.

Produces
Produces converts the energy from the sun to chemical energy and stored as food during photosynthesis thus they are either directly or indirectly affect other organisms as they provide energy and oxygen.
Consumers
they feed on other organisms thus all animals are consumer. Herbivores are primary consumers while carnivores are secondary consumers and carnivores that feed on carnivores are tertiary consumers.
www.longleat.co.uk

Decomposes
They achieve their energy by breaking down dead faeces and excretory products

http://infohost.nmt.edu/~klathrop/East%20Mountain%20High%20School%20Virtual%20Nature%20Trail.htm

no organism is independent

Organisms rely on one another , they are interdependent on each other . the populations in a community live interdependently , any change one population affects the other populations and eventually the whole system.

physical features of environment which affect organisms

1) light intensity: It affects the distribution and growth of both plants . green plants grow in areas where there are sufficient light .for survival the plants have got adaptations which enable them to get light .there are also some plants which are adapted to screen off excess light.
2) Temperature: it affects rate of reactions of enzymes , which control metabolic activities of plants and animals .many organisms are not able to tolerate extreme temperature. This is hazardous as too high or low a temperature is able to kill an organism. some flowering plants are adapted to change in seasons as they have special attributes like storing food during winter
3) Amount of available water: this is one of the most essential factors as no organism is able to sustain without water for a prolonged period of time. This factor is also dependent on amount of rain and pattern in which rain falls the whole year. Only those organisms with certain adaptation are able to survive in places where water is scarce. Xerophytes reduce their rate of transpiration by shedding leaves or reducing leaves to spine.
4) Oxygen content: most organisms are aerobic thus they require oxygen for respiration , and are not able to survive in places with a lack of oxygen. However there are a few exceptions . these organisms possessed unique adaptations so as to get oxygen. Like mangrove plants which have pneuatophores.
5) Salinity: this refers to the salt concentrations of water and soil . the organisms living in sea have adaptations , to prevent water loss from body . amoeba have contractile vacuoles to prevent excess water in body which enters by osmosis
6) Ph: this term refers to the acidity or alkalinity of a solution . the ph in the habitat affects the organism as some species are ph sensitive , and drastic change in ph could cause death. Some fishes adapt by secreting the excess salts taken by the body through the skin

Ecology is the study of organisms interacting with one another and their surroundings.
The following are some key terms on ecology
1) habitat: the place where an organism lives. eg:coral reefs is a habitat of clown fish

http://en.wikipedia.org/wiki/Clownfish
2) population: A group of organisms of the same living in a habitat. Eg: the redshanks that lives in mangrove swamps consist of a population.
www.ecologyasia.com/html-loc/sungei-buloh.htm

3) Community: All the populations of organisms which live and interact with one another in a habitat.
4) Ecosystem: A community and its abiotic environment together makes up an ecosystem

www.scienceclarified.com/Di-El/Ecosystem.html
They are all related as populations of organisms live and interact with one another make up a community.
populations→communities→ecosystems.