 Producers include many photosynthetic bacteria, producers includes algae, producers includes plants all of the plants without those plants no life no life is possible they do photosynthesis utilizes carbon dioxide and water and sunlight energy and makes energy in the chemical form that is usually called ATP the adenosine triphosphate and makes carbohydrates for the use by themselves and for the use for the consumers. We call the producers the entry point of energy inside an ecosystem. Let us have a look on some plants you can see in this picture that plants are growing on a rock on the bank of a river then comes the consumers. These are the second level of feeding or we can call second trophic level but these are themselves divided into further levels as we looked at in a pyramid. Consumers utilizes organic carbon source they can eat upon plants or they can eat upon other animals. Consumers uses utilizes the carbohydrates produced by the plants. Their types are primary, secondary and tertiary consumers. Tertiary consumers which eat upon plants we also call them herbivores then comes the secondary consumers we also call them carnivores they eat upon the herbivore animals. Then comes tertiary consumers which eat upon the other carnivores then we have another category called omnivores we say herbivores the organisms animals which feed upon plants the carnivores the animals which feed upon other animals the omnivores which eat upon both plant and animal material for example human beings we are omnivores we eat vegetables plants we also eat beet the animals so omnivores are the organisms who can feed upon both animal and plant sources they can if they get animal they can eat animal and spas if they get plant for their food they can get plant for their as their food. Few animals you can see a red panda in this picture which is eating some leaves of tree so it is a herbivore an elephant a very huge and large animal but it also feed upon the plants it is a vegetarian animal a consumer a cat it is eating you can see in the picture that it is eating a bone bones you know are the part of animals body so it is a carnivore. Then you can see another carnivore an eagle which is attacking upon a pigeon pigeon we know eats grains so pigeon is a plant eater and the eagle is a carnivore that is the meat eater which is eating upon the pigeon omnivores bears bears can eat both plant and animal matter if they get an animal to eat a small animal they eat upon it if they get plants legumes or other plants they eat upon the plants so they are also omnivore like us then comes the decomposers decomposers are two major groups one are called fungi fungi is a major group which particularly eat upon the dead organic matter then there are lot many types of bacteria which are present in soil in water and other places which break up the dead organic matter and utilize it for making their own food and energy and then they convert those organic matters into small organic molecules these small organic molecules are later utilized by the plants plants actually absorb those inorganic or organic matters from the soil with the help of their roots and the roots gets those materials and make them part of the plant body so decomposers are extremely important because number one they convert all the dead organic matter which is present in large quantities otherwise and could be accumulated and could be bad for environment they convert those dead or dead organic materials into more usable forms and more better forms for the environment so decomposers and secondly decomposers convert the materials into usable forms which are used by the plants so a cycle continues and energy in the ecosystem which is which is coming through sunlight through produces keep flowing in the form of a cycle and the abiotic components there are lot many abiotic components that is non-living components present in an ecosystem the abiotic components the non-living components for example water light air soil water for example is one of the most important abiotic components of an ecosystem water is a limiting factor for the growth and for development of life because we know that water is required for all the life forms to live to continue their life processes water is involved to support life for example plants when they are growing they need water for converting energy from one form to another form they need water animals need to drink water for their metabolic processes they require water water is part of their body light is also very important factor because we know all the energy is coming which is coming inside the ecosystem is coming in the form of sunlight sunlight have energy which is utilized by the plants to make their chemical energy that they can use because sunlight energy they cannot use directly they have to convert it into some chemical form of energy and also plants utilize the sunlight energy to make their food by photosynthesis and the carbon cycle then air is also very important factor because air many most of the times air manages the temperature of the environment and air currents are also responsible for different process of life for example distribution of spores of a plant it depends upon many times air currents then soil soil is very important about a factor because soil is the place to support the plant life and animal life particularly plants grow in specific types of soils soils have their own properties they have their particle size they have pores in it different types of soils have different pore sizes in in themselves and these pores accommodate water these pores accommodate gases and the soil also have soil also have different types of bacteria which convert or decompose the organic matters so soil is also a very important a biotic factor then comes rain rain is also very important factor because when the waters the water bodies they evaporates and the water go in the atmosphere in the form of vaporized water and makes clouds then it causes the raining rain is very important because it provides a runoff water which is available to plants and to other life forms for for example for animals for their drinking and for supporting the plant life in the soil so a biotic factors they are as important as the biotic factor factors living organisms animals the plants in an ecosystem let us have a look a brief look on a picture on a diagram which shows that how energy flowing in an ecosystem and how a biotic factors are interaction with the biotic factors you can see on a site a water body from which through evaporation water is going towards the atmosphere due to the heat of sunlight that water these water vapors collect and condense in the atmosphere to make clouds and these clouds when they rain then they produce a rain this rain is returning that water back to the environment you see you can see the rain on the mountains and then the rain water is coming down and this water is supporting a lot of life different types of plants different types of animals and then slowly this runoff water is going down down down back to the same place from where it was evaporated and then you can see that there are different types of plants which are utilizing the sunlight energy to make their food and then these plants are eaten up by the animals those animals are eaten up by the other animals you can see a bird and then all of these organisms are going back when they die or they shed their parts like plants they are going back to the soil and the decomposer in the soil they are breaking them up into smaller pieces very very small molecules organic and inorganic molecules which are again taken up by the plants make the part of their body and then they come back to the cycle you can see a desert ecosystem now we are going to cover some examples of different types of ecosystems in the world and in Pakistan there are two terms climate and weather weather is a short-term change in any of the abiotic factor like temperature for example we know that temperature of the day is different and of the night is different the seasonal changes are there the climate actually represent long term changes in environmental factors for example due to greenhouse fact we know the temperature of the earth has risen to about 1 to 2 degree centigrade so climate represent long term changes in an environment and the climate of an area is responsible for making different types of ecosystem ecosystems and let them develop and grow we divide ecosystems into two major categories the aquatic ecosystems and the terrestrial ecosystems aquatic ecosystems ecosystems present in water and terrestrial ecosystems ecosystems present on land