Key Features and Types of Natural Ecosystems Explained
An ecosystem can be defined as a community where living beings co-exist in their physical environment and interact with each other to maintain the lifecycle and facilitate the flow of energy and nutrients. It consists of two main components – biotic and abiotic.
Biotic components include plants, animals, and other living organisms. The physical elements in an ecosystem such as temperature, mineral, rainfall, and humidity make up the abiotic components. Ecosystems can be found anywhere and vary greatly in terms of size and types. It can range from a garden, freshwater ponds to vast oceans and forests.
Types of Ecosystems
There are two types of ecosystems:
Natural Ecosystem – These are ecosystems that occur naturally and can survive without any intervention from human beings. Examples of natural ecosystems are forests, mountains, rivers, etc.
Human-Made or Artificial Ecosystem – When human beings modify the already existing ecosystem to meet their purpose or create an ecosystem of their own that mimics the natural condition, those are called artificial ecosystems.
One of the main differences between natural and artificial ecosystems is that the latter requires constant attention as they are not self-sustainable. Examples of this type of ecosystem include aquariums, crop fields, gardens, dams, etc.
In this article, we will focus on naturally occurring ecosystems only.
Natural Ecosystem
Natural ecosystem definition is that it is an ecosystem found in nature where organisms freely interact with other components of that environment. One of the main characteristics of this ecosystem is that it is a self-sufficient system.
For instance, a forest has both herbivores and carnivores. Herbivores consume grass, fruits, and seeds. They are in turn, consumed by the carnivores. When carnivores die, their body decomposes into the soil and provides it with essential nutrients which help in the growth of trees and grass, which is consumed by herbivores. Thus, the biological cycle continues.
Categories of Natural Ecosystems
There are two types of natural ecosystems:
Terrestrial Ecosystem: These refer to the ecosystems found on land. They can be classified based on climate and temperature. These are discussed in detail below:
1. Forests:
They comprise about 31% of the total land on the Earth. Based on the climate condition and type of forest, there are three different kinds of forest ecosystems in the world. These include temperate forest, tropical rainforest, and coniferous forest.
A tropical rainforest is seen in areas that experience heavy rainfall. A coniferous forest can be found in cold, mountainous regions, unlike temperate forests which grow in areas with warm summers and cold winters.
They act as habitats for a large variety of animals, birds, insects, and other organisms, being the world’s largest terrestrial biodiversity. Additionally, we also rely on forests for a number of things.
2. Deserts:
There are two types of deserts – hot and cold. These ecosystems have extreme weather conditions – the air is dry, the weather is too hot in the day and too cold at night, and they receive very little rainfall. As a result, the vegetation is sparse and very few animals live in the desert. Camels, desert snakes, and scorpions are few insects and animals that can be found in a desert.
3. Grasslands:
Some of the examples of natural ecosystems of this type are temperate grasslands and tropical savannahs. The significant vegetations are tall grass with few shrubs and trees. Animals that can be seen in the grasslands are rabbits, wolves, zebras, gazelles, etc.
Aquatic Ecosystem:
As the name suggests, these include the ecosystems found within water bodies. They are the most common types of ecosystem found on the Earth as water covers around 75% of the Earth’s surface. It is divided into two groups –
1. Freshwater – Freshwater constitutes only about 3% of a total 75%. Some examples of natural ecosystems that fall within this category are lakes, rivers, ponds, streams, wetlands, etc.
Rivers and streams originating from mountains carry essential nutrients which are then deposited in lakes and ponds. Freshwater is also the habitat for a variety of plants, animals, and microbes.
2. Marine Ecosystem – This is one of the most diverse forms of ecosystems. It consists of coral reefs, kelp forests, mangroves, salt marshes, rocky shores, deep sea, the open ocean, and so on.
Marine ecosystems depend on physical factors like high salt content, availability of light, temperature, tides, geology, and geography. For this reason, some areas, such as mangroves, and salt marshes, are full of life, while the presence of life in areas such as the abyssal plain at the bottom of the sea is scarce.
FAQs on What Is a Natural Ecosystem?
1. What is the primary definition of a natural ecosystem?
A natural ecosystem is a biological community of interacting organisms (biotic components) and their physical, non-living environment (abiotic components) that has developed and functions without any significant human interference. It is self-sustaining and regulated by natural processes like energy flow and nutrient cycling.
2. What are the main components of any natural ecosystem?
Every natural ecosystem is composed of two primary types of components:
- Biotic Components: These are all the living or once-living parts of the ecosystem. They include producers (like plants that make their own food), consumers (like animals that eat other organisms), and decomposers (like bacteria and fungi that break down dead material).
- Abiotic Components: These are the non-living chemical and physical factors in the environment. Examples include sunlight, temperature, water, soil composition, and atmospheric gases.
3. How do natural and artificial ecosystems differ?
The key difference lies in their origin and sustainability. Natural ecosystems (e.g., a forest) are self-regulating, possess high biodiversity, have complex food webs, and maintain a closed-loop nutrient cycle. In contrast, artificial ecosystems (e.g., a crop field or an aquarium) are man-made, require constant human intervention for maintenance (like adding fertilisers or food), have low biodiversity, and feature simple food chains.
4. What are the major types of natural ecosystems with examples?
Natural ecosystems are broadly classified into two main categories:
- Terrestrial Ecosystems: These are land-based ecosystems. Major examples include forests, grasslands, deserts, and tundra.
- Aquatic Ecosystems: These are water-based ecosystems. They are further divided into Freshwater Ecosystems (like rivers, lakes, and ponds) and Marine Ecosystems (like oceans, coral reefs, and estuaries).
5. What makes natural ecosystems self-sustaining while artificial ones require human intervention?
Natural ecosystems are self-sustaining due to three core factors. First, they have high biodiversity, ensuring that various ecological roles are filled. Second, they possess complete nutrient cycles, where decomposers efficiently return nutrients from dead organic matter back to the soil for producers. Third, they feature complex food webs that create resilience. Artificial ecosystems lack this complexity and biodiversity, making their nutrient cycles incomplete and requiring humans to manage energy inputs and waste removal.
6. Can an ecosystem like a pond be considered truly natural?
It depends on its origin. A pond that forms naturally through geological or ecological processes is a perfect example of a natural freshwater ecosystem. It contains a balanced community of plants, animals, and microbes. However, a pond created by humans, such as a garden pond or a fish farm, is considered an artificial ecosystem because its existence and stability depend on human maintenance like stocking fish, managing water levels, and controlling algae.
7. Why is energy flow, not cycling, a key principle in a natural ecosystem?
Energy in an ecosystem follows a unidirectional path; it does not cycle. It originates from the sun, is captured by producers (plants), and is then transferred through different trophic levels (consumers). At each transfer, a significant amount of energy is lost as heat, as described by the 10% rule. This energy cannot be reused by the producers. In contrast, nutrients (like carbon and nitrogen) are finite and are continuously recycled by decomposers, making them available again for the producers. Therefore, energy is said to 'flow' through an ecosystem, while nutrients 'cycle' within it.
