ecological succesion n ecosystem regulation

Slide 1: 

ECOSYSTEM REGULATION All Ecosystems regulate to maintain themselves under a set of environmental conditions. Also known as Biological Equilibrium. Any environmental stress tries to disturb the normal ecosystem, the ecosystem, by itself tries to resist the change and maintain itself in equilibrium, this property is known as HOMEOSTASIS. The system can show this tolerance or resistance only within a max. or min. range. This range of tolerance is known as Homeostatic Plateau.

Slide 2: 

COUNTERACT MECHANISM If any stress tries to disturb this equilibrium then the system has its own mechanism to counteract this disturbance which are known as:- Negative feedback mechanism Positive feedback mechanism

Slide 3: 

POSITIVE FEEDBACK The increase in the population of the organisms at the different levels increases the population of organisms at a lower level and is known as the positive feedback mechanism. For example:- When the population of plants increases it leads to increase in the population of herbivore animals. It increases the population of frogs and birds. NEGATIVE FEEDBACK Deviation counteracting mechanisms which try to bring the system back its ideal conditions, this is known as negative feed back mechanism. For example:- The increased population of insectivorous animals acts on the herbivorous insect by the process of predation

Ecological Succession : 

Ecological Succession

Primary Succession : 

Primary Succession Soil starts to form as lichens and the forces of weather and erosion help break down rocks into smaller pieces When lichens die, they decompose, adding small amounts of organic matter to the rock to make soil Simple plants like mosses and ferns can grow in the new soil. The simple plants die, adding more organic matter.

Primary Succession : 

Primary Succession

Secondary Succession : 

Secondary Succession Begins in a place that already has soil and was once the home of living organisms Occurs faster and has different pioneer species than primary succession Example: After forest fires, the soil remains intact, thus, the area return to its natural community. Because these habitats previously supported life, secondary succession, begins on substrates that already bear soil.

The Circle of Life in Secondary Succession : 

The Circle of Life in Secondary Succession

Why Does Ecological Succession Occur? : 

Why Does Ecological Succession Occur? Because it is the process of life for plants, soil and other living organisms. Because organisms alter soil structure, chemistry, and microclimates, the species composition of ecological communities constantly changes over time. Succession will continue until the environment reaches it’s final stage…the Climax Community.

Climax Community : 

Climax Community A stable group of plants and animals that is the end result of the succession process Does not always mean big trees Grasses in prairies Cacti in deserts

Does Ecological Succession Ever Stop? : 

Does Ecological Succession Ever Stop? We must recognize that any ecosystem, no matter how inherently stable and persistent, could be subject to massive external disruptive forces (like fires and storms) that could re-set and re-trigger the successional process. As long as these random and potentially catastrophic events are possible, it is not absolutely accurate to say that succession has stopped.

CONCLUSIONS : 

CONCLUSIONS Contribute to negative feedback mechanism. Slow down the process of ecological succession by using less pesticides. Removal of weeds by herbicides which humans do every growing season because of the force of ecological succession.

Prepared by:- : 

Prepared by:- Ronit Madan A-42 (10ME 106) Sahil Garg A-43 (10CS 085) Shalini Sharma A-45 (10EC 119 ) Sankalp A-44 (10CS 098) Shashi Kant A-46 (10ME 118 )