ENVIRONMENTAL

PROJECT

By-MAHADEV KANGRALKAR

11ME08

date.14/12/2011

Energy flow in the ecosystemEcological successionFood chains , food web & ecological pyramids

TOPICS

Energy flow in

the ecosystem The community of independent

organisms along with the inorganic components

(chiefly soil, water, air, and rocks) that make up our

ecosystem/environment

ENERGY CYCLEEnergy cycle is based on the flow of energy through the

ecosystem That is flow/transfer of energy from one body to another for eg 1,000 carrots to support 100

rabbits, 10 owls, and one hawk. mainly sunlight is at the apex of all energy cycle

The Water cycle

Water cycle is common to us. The rain water which falls on ground flow into rivers/sea or falls directly into the sea gets evaporates due to solar energy and some rainwater

which percolates into the ground is drawn up by plants. These water then transpired from

leaves as water vapor. This vapors are lighter then air so they rise high and forms

clouds as clouds rise higher. The vapor condenses and changes into droplets which

falls on the land as rain

The Carbon cycleThe oxygen on which the whole mankind & animal kind depend is generated through

this cycle. In the atmosphere carbon occurs as carbon dioxide (co2). In the presence of sunlight plants take carbon dioxide from

atmosphere through their leaves the carbon dioxide from soil is also absorbed by their roots. In the presence of sunlight they are able to to form carbohydrates that contain

carbon this process is known as photosynthesis. In these process plants

releases oxygen into atmosphere on which animals depend for their respiration animals release carbon dioxide during respiration so they return fixed carbon to the soil and also when they die they return their carbon to

soil

The Oxygen cycleOxygen cycle and carbon cycle is linked with each other oxygen is absorbed by plants and animals from air during their respiration and gives carbon dioxide these carbon dioxide is absorbed by

plants during photosynthesis and give out oxygen

The Nitrogen cycle

Herbivores feed on plants carnivores feed on herbivores thus the bodies of

dead plants and animals or their wastes material is broken down by worms &insects mostly beetles and ants these small soil animals breaks

the waste material into smaller bits on which microscopic bacteria &fungi can act this material is broken down further into nutrients that plant absorb & use

for their growth in this manner nutrient are recycled back from animal to plants

Ecological SUCCESSIONEcological succession is a

process through which ecosystem tends to change

over a period of time succession can be related to

seasonal environmental changes which create change

in the community of plants and animals living in the

ecosystem

Primary successionSecondary succession

Cyclic succession

*Types of succession

Primary successionSuccessional dynamics beginning with colonization of an area that has not been previously occupied by an ecological community, such as newly exposed rock or sand surfaces, lava flows, newly exposed glacial tills, etc., are referred to as primary succession.

Secondary succession

Successional disturbance or removal of a pre-existing community are called secondary succession. Dynamics in secondary succession are strongly

influenced by pre-disturbance conditions, including soil development, seed banks, remaining organic matter,

and residual living organisms. Secondary succession is much more

commonly observed and studied than primary succession.

Cyclic successionUnlike secondary succession, these types of vegetation change are not dependent on disturbance but are periodic changes arising from fluctuating species interactions or recurring events. These models propose a modification to the climax concept towards one of dynamic states.

Factors Influencing Succession

The trajectory of successional change can be influenced by site conditions, by the interactions of the species present, and by more stochastic factors such as availability of colonists or seeds, or weather conditions at the time of disturbance. Some of these factors contribute to predictability of succession dynamics; others add more probabilistic elements. In general, communities in early succession will be dominated by fast-growing, well-dispersed species As succession proceeds, these species will tend to be replaced by more competitive species.

Food chains, food web and ecological pyramids

The transfer of energy from the source in plants

through a series of organisms by eating and

being eaten constitutes food chains. The

interconnection between different food chain is

known as food webs. Each step of the food web

is called tropic level these tropic level to gather

form the ecological pyramid

Food ChainsFood chains are the sequence of

feeding relationships through which plants and animals depend on each other for food. Food provides the

nutrients plants and animals need to build and repair their body parts, and

the energy they need to grow and function. There are countless food chains involving different plant and

animal species in a variety of habitats all around the world. Every plant and animal belongs to at least one food

chain, and these chains can be simple or very complex.

*In an ecosystem there are a very large number of interlinked food chains, these forms a food web

*Food Webs

Ecological pyramids The green plants the producers in ecosystem form the first trophic level in food pyramid. The herbivores that eat plant are at the second trophic level and are called primary consumers the predators that feed on them form the third trophic level and called carnivores they are at the apex of food pyramid

11ME0809/01/12

The End