An ecosystem is defined as the complex system of living organisms, their interrelationship and their physical environment. These all comprise a particular unit of space. An ecosystem is categorised into the following factors. These are the factors of an ecosystem on which the whole ecosystem relies on.
Biotic factors - All living members
Abiotic factors - Minerals, climate, soil, water, sunlight and all other non-living things.
The fundamental source of energy is from the sun. The energy is used by the ecosystem’s autotrophs, self-sustaining organisms. It consists mainly of green vegetation, which is capable of photosynthesis. It uses the sun’s energy to convert carbon dioxide and water into energy-rich carbohydrates. The autotrophs use this energy stored as carbohydrates to form complex compounds such as proteins, lipids, starch, etc. These all maintain an organisms’ life process. The autotrophic level of the ecosystem is termed as producer level, as these are the driving force of the cycle.
The organic matter generated from autotrophs sustains the other level, i.e., the heterotrophs. These are also termed consumers as they cannot make their food and have to rely on producers for their food. They decompose the complex organic material built up by autotrophs. Animals, bacteria, fungi and other microorganisms come under the category of heterotrophs.
The autotrophs and heterotrophs together make up various feeding levels in an ecosystem. The components of the ecosystem are explained in brief in the following pointers:
The producer level: It composes those organisms that make their food.
The primary consumer level: It composes those organisms that feed on the producer level.
The secondary consumer level: It composes those organisms that feed on primary consumers.
The movement of organic matter and energy consumption from the producer level to the final consumer level makes up a food chain. However, in the process of forming a food chain, it becomes a food web as the ecosystem overlaps and interconnects. The final link in the food chain is always made up of the decomposers (heterotrophs that break down dead organisms and wastes).
(Image will be Uploaded Soon)
Components of Ecosystem
We will consider an ecosystem from a structural perspective. An ecosystem consists of biotic and abiotic components. We observe that organisms living in any ecosystem are nowhere identical, but can be categorised into species. These species provide their contribution towards an ecosystem. The example would include the number of species, number of individuals of each species and their distribution across an ecosystem.
Then comes the functional component of an ecosystem. It comprises of:
Abiotic factors: Abiotic factors are the chemical or physical factors that act on the living organisms as part of their living or life. They are also referred to as ecological factors. The physical and the chemical factors form the abiotic component of an ecosystem and are the characteristics of the environment, light, air, soil, nutrients etc. Generally, the abiotic factors of the ecosystem vary from one ecosystem to the other. Water pH sunlight turbidity salinity e-water death available nutrients and dissolved oxygen are some of the abiotic factors that are included in the aquatic ecosystem. Similarly, soil type rain wind temperature altitude sunlight and nutrients are some of the factors that are essential in terrestrial ecosystems.
The energy source for the terrestrial ecosystem is the Sun. The plants in presence of sunlight synthesise the food in presence of carbon dioxide and chlorophyll. Through various chemical reactions, the energy of the sun is finally converted into chemical energy. Herbivorous plants usually depend on the plants that synthesise food for their energy. The carnivorous animals feed on herbivores and other carnivores. The leftovers of the preyed animals and plants are there and decomposed at any level by microbes that feed on BK and dead organic matter. The molecules are then released back to the environment post decomposition after various chemical reactions in form of chemicals.
Therefore the ecosystem has a complex set of interactions that usually happens between abiotic and biotic components. These components of the ecosystem are linked with one another through the nutrient cycle as well as the energy flow. Though no ecosystem has a definite boundary to it, if one factor is changed or removed in the ecosystem the other interactions also get affected accordingly. This has the power to ultimately affect the entire ecosystem.
Biotic Factor: The living components which are present in the ecosystem are referred to as biotic components. Some of the biotic factors include plants, animals, fungi as well as bacteria. Based on the energy requirement source these biotic components can be further classified into producers, consumers and decomposers that are considered as the three broad factors of biotic components.
Producers: Producers are referred to as plants that can synthesise their own food and energy requirements through photosynthesis in presence of sunlight and chlorophyll. All the other living creatures are dependent on plants for their energy requirement as well as for food in oxygen.
Consumers: Herbivorous carnivorous and omnivorous are the three categories that make the consumers. The herbivorous are the living organisms that survive on plants full stop carnivorous are the living creatures that eat other living organisms. Wild omnivores are living organisms that feed on both plants and animals.
Decomposers: Decomposers are also known as saprophytes that comprise fungi and bacteria. They basically feed on dead indicate plants and animals and convert them into nitrogen and carbon dioxide through various chemical reactions. Saprophytes are a very essential part of the ecosystem cycle as it plays a vital role in recycling the nutrients that can later be used up by the producers that are planted to generate their own energy requirements.
To survive, an ecosystem needs five basic components. All other components follow after. The various components further include energy, minerals, nutrients, water, oxygen and living organisms. Most of the energy in an ecosystem comes from the Sun. It consists of interdependent and interacting elements of the natural environment in a geographical area. The elements of an ecosystem consist of both living as well as non-living things. The material elements cycle through an ecosystem via the food chain and other pathways.
It is by far considered one of the major processes in an ecosystem. It is obtained initially from the Sun and then moves through the food chain. At each stage, the consumer only retains a fraction of the energy it takes in. The remaining energy is dissipated as heat and cannot be recycled further. It is considered an open system concerning energy as it depends on continued energy flow and loses energy in the process.
After energy, the other major process in an ecosystem is the cycling of material in the form of nutrients. Unlike energy, the material is not entered into an ecosystem from any external source. Rather, it is chemically transformed. No material is lost in the cycle. It is also considered as a closed system concerning material flow. The movement of elements of an ecosystem such as carbon, phosphorus and nitrogen through the ecosystem is known as biogeochemical energy.
Energy and nutrient availability constraint an ecosystem’s productivity. In the ocean, light is plentiful at the surface but becomes scarce deep down. Nutrients also become scarce, so productivity is limited. These are certain considerations included while discussing an ecosystem in brief. At all levels, no resource will be equally distributed.
Food Chain and Web
A food chain is a chain that shows how organisms are linked to each other through various foods and energy levels. Whereas a food web shows how food chains are connected to each other. A single food web can consist of one or more food chains. Usually, a food chain starts with a producer and ends with a top carnivore animal. Therefore the trophic level of an ecosystem is attained when the energy flows from one level to another level in a food chain. The producers come as the first trophic level which is followed by Harvey was that are considered as primary consumers and then small Carnivorous was never considered as a secondary consumer and finally the large Canvas is considered as cursory consumers which occupy the fourth trophic levels.
At all levels, all the resources will be equally distributed and all the living and nonliving organisms live in harmony with each other. It results in maintaining a healthy food chain and a healthy ecosystem.