Ecosystem

Introduction

We all live on this earth along with our environment and surrounding. Our environment consists of various biotic and abiotic factors like air, forest, soil, water, various non- living things and other different types of living organisms. We cannot live without environment. Not only we but also other living organisms cannot live without environment and its factors. Everything living organisms on this earth are interrelated with eachother. We are connected with various factors of the environment directly or indirectly. These factors may be whether living or non- living things. The ecosystem consists of very minute organisms to the huge organisms.
There are various types of green plants like grass, trees, different types of herbs and shrubs. These green plants are known as the producer as they produce foods. These grasses are eaten by the consumer. Consumers are further divided into different types like herbivorous and carnivorous. After the grass is eaten by consumer like deer, the deer is then eaten by primary consumer like a fox. After the fox eats the grass, the fox is again eaten by top consumer like a lion, tiger etc. They are named as the top consumer because they ar not further eaten by other organisms. After the dead of the top consumer, they are decomposed by decomposers like bacteria, mushroom etc. This decomposer changes the complex organic compounds into the simpler form which are used by the producer to produce food.
Like this , every part and the member of the environment are directly or indirectly interconnected with eachother. Therefore, the ecosystem can be defined as a dynamic system where all the biotic and abiotic components of the earth are interrelated directly or indirectly with eachother and are constantly interacting, bringing structural and functional changes. There are two different types of ecosystem. They are terrestrial ecosystem and aquatic ecosystem that are concerned with land and water respectively. Short information about aquatic and terrestrial ecosystem is given below,

• Terrestrial Ecosystem
  Producer: grass, trees, herbs, and shrubs
  Primary consumer: deer, zebra, goat
  Secondary consumer: jackal, fox
  Tertiary consumer: lion and tigers
• Pond Ecosystem
  Producer: hydrilla, algae, etc.
  Primary consumer: small fishes, tadpole, dragonfly etc.
  Secondary consumer: frog, big fishes etc

All the living organisms on this earth cannot live without food. We need the energy to perform our life activities which are only provided by the food. The lion cannot run without eating its food, the goat cannot run without eating grass and many other organisms cannot do their activities without food. All these organisms get food from each other directly or indirectly. They are interconnected with each other in terms of food also. This connection of living organisms for food is known as food chain.

Food Chain

The transfer of energy and materials in the form of food from one trophic level to another trophic level by the repeated process of eating and being eaten is known as food chain. It is of three types: grazing food chain, detritus food chain and parasitic food chain.

Grazing food chain

This type of food chains begins from living plants and goes on grazing herbivores and on to the carnivores. It starts from plant base and goes from smaller to larger animals.

Producers (first trophic level)→ Herbivores (Second trophic level)→ Carnivores(Third trophic level)

Detritus food chain

These types of food chain are characterized by the following ways:

1. The primary source of energy for detritus food chain is dead organic matter called detritus.
2. Main sources of dead organic matter are dead leaves or dead animals.
3. These are shorter than the grazing food chain.
4. Primary consumers are the detritivores (detritus eating).
5. The detritivores, in turn, are eaten by secondary consumers like larvae, nematodes etc.

Parasitic food chain

In this type of food chain, energy goes from large organisms to smaller ones without killing.

Trophic level

The producer consumer arrangement is known as trophic structure and the position that an organism occupies in a food chain is called trophic level. In grassland there are four types of trophic level. From the trophic level we can say that the transfer of energy and materials takes place from one trophic level to another trophic level through food chain.

Food web

A food web is a network of food chains interconnected at various trophic levels. The food web provides the alternative pathways of food availability.

Interrelationship between animals and foods

Plants and animals are closely interconnected with eachother for food. When decomposer decomposes dead and decayed animals into simpler compounds, these compounds are used by plants to produce food. These foods are then eaten by various herbivorous animals. On the basis of food, organisms are divided into two types which are given below,

Autotrophs

Autotrophs are those organisms that can make their own food. They are also called producers. Autotrophs are the green plant which contains chlorophyll. They synthesize organic foods from inorganic materials. The green plants produce organic compounds, sugars from carbon dioxide and water by the process of photosynthesis.

6CO₂ + 6H₂O → C₆H₁₂O₆ + 6O₂

Heterotrophs

Those organisms which cannot prepare their own food and depends on upon autotrophs for food are called heterotrophs. They come under consumer and decomposer. On the basis of nature of food, heterotrophs are divided into the following categories:

• Holozoic: This includes those organisms which feed on solid organic substances obtained from other organisms. They can be of three types: herbivorous, carnivorous and omnivorous.
• Saprophytic: These types of organisms feed on dissolved organic and inorganic substances produced as a result of decomposition of plants and animals. Examples: euglena, bacteria etc.
• Parasitic: Parasitic organisms like an earthworm, tapeworm, liver fluke etc. obtain their liquid or solid food from other living organisms.

Ecosystem Services

We get various services from the ecosystem. They are discussed below in terms of provisioning services and regulating services.

Provisioning ecosystem: We get foods, wood, and various products from the ecosystem. There are various provisioning services which are given below,

• Food and fibre: We need the energy to perform our life activities. We get energy from food and we get food from the ecosystem. We get fibres like jute, wood, silk, etc from the forest and various types of animals.
• Fuel: Various things like wood, waste of animals and various things from ecosystem are used as fuel. We get this types of fuel from our environment.
• Ornamental resources:Various ornamental are made by carving wood, metals, bones etc. We get wood, metals etc from the ecosystem.

Regulating services: Ecosystem regulates various factors of the earth. Some of them are discussed below,

• Climate regulation: Ecosystem greatly affects the climate of the world. The forest regulates the temperature of the earth and helps in rainfall. It gives out carbon dioxide that contributes to climate change.
• Water Purification: The ecosystem performs an important role in purifying water. They filter the water and remove aquatic germs through the different process. The ecosystem also helps in pollination, regulation of human diseases and erosion control.
• Cultural services: Ecosystem contributes in natural scenery, fresh environment, culture, and tradition etc. Ecosystem effects in religious and cultural change. It promotes the social relation and cultural heritage. It also greatly contributes to the tourism industry.
• Supportive services: Ecosystem supports nutrient recycling among plants,primary production, and soil formation. It regulates food production and purifies water.

Basic requirement of human

We need various things to live our life. Some things are very important while other are not so important. Important things are termed as basic needs. The basic needs of the human are food, shelter and clothing. Among this, food is one of the very important needs of our life because our body cannot perform life activities without food as food provide us energy. We cannot live outside. We need a roof above us to prevent us from rain, strong wind, sunlight etc. We need something that protects us from fire, animals, criminals etc. We become safe from all these things if only we stay inside our house. We cannot sleep outside as it is very dangerous to our health and life. So, shelter is very important for humans as there are many dangerous things outside including natural disaster.

Another basic need of humans is clothing. Clothing is very important for us as it protects us from various things like germs, dirt, etc. We cannot walk naked around our home. We need clothes to protect our body. These all basic needs of human life does not evolve from anything but instead, all these things are provided by the ecosystem or the environment on which we live. Human beings depend on upon different biotic and abiotic factors of the ecosystem. Some topic are discussed below how the human beings have depended on ecosystem for their basic needs.

• Food: We need food to survive. We cannot live without food. Food provides us energy. Our body use foods to perform various functional activities. We eat vegetables, fruits, meats etc. We get all these things from the ecosystem. We grow vegetables and fruits on soil which is the part of the ecosystem. We cannot get food without the ecosystem.
• Shelter: Home is very important for us. We cannot stay outside. To make house we used woods, bricks, muds,etc which are the abiotic factors of the ecosystem. We are very much dependent on the ecosystem.
• Clothes: We cannot walk without clothes. We need clothes to protect our body from various germs, dirt, etc. We do not obtain clothes directly from the ecosystem. Industries made clothes by using various parts of the ecosystem like cotton, wool, silk etc.