Maarg Manthan · Topic 1.13

Distinction Between Ecology, Environment and Ecosystem

Environment & Ecology › Basic Concepts of Ecology · Topic 1.13

Ecology, environment and ecosystem are related but different terms. Ecology is a branch of science: the study of the relationships between living organisms and their surroundings, named by Ernst Haeckel in 1866. Environment is the sum total of all the living and non-living surroundings of an organism, including physical, chemical and biological factors, and also social and cultural factors for humans. In India, the Environment (Protection) Act, 1986 defines environment to include water, air and land and the interrelationship between them and human beings, other living creatures, plants, micro-organisms and property. An ecosystem is a functional unit of nature in which living organisms interact with each other and with their non-living environment, through energy flow and nutrient cycling. Tansley coined the term in 1935.

5 min read · UPSC Prelims · Environment & Ecology · Basic Concepts of Ecology

At a Glance

Ecology Science of relationships
Environment All surroundings
Ecosystem Functional unit
Ecology coined Haeckel, 1866
Ecosystem coined Tansley, 1935
Exam link UPSC Prelims, Environment & Ecology: Basic Concepts of Ecology

Where Does It Fit?

This is the last topic of the macro on basic concepts of ecology. It clears up three terms that are often confused, before the next macro studies ecosystems in detail. Previous topic: Range of Tolerance and Maximum Range. Next topic: homeostasis Stability…">Definition, Functions and Properties of an Ecosystem.

How Do the Three Terms Differ?

Aspect	Ecology, environment and ecosystem
Nature	Ecology: a science or subject of study. Environment: the surrounding conditions. Ecosystem: a real natural unit
Meaning	Ecology: relations between organisms and their surroundings. Environment: everything around an organism. Ecosystem: community plus its non-living environment as one functioning system
Coined by	Ecology: Ernst Haeckel (1866). Ecosystem: A G Tansley (1935). Environment: older general word
Components	Ecology has no components, it is a study. Environment has physical, biological and cultural parts. Ecosystem has abiotic and biotic components
Scale	Ecology studies all scales. Environment is defined for an organism or a place. Ecosystem can be any size, from a pond to a forest
Focus	Ecology: interactions. Environment: conditions. Ecosystem: energy flow and nutrient cycling
Example	Study of a tiger and its prey is ecology. The forest conditions around the tiger are its environment. The whole forest functioning as a system is an ecosystem

How Is Environment Defined in Law and Science?

Environment Protection Act, 1986: Section 2(a) defines environment to include water, air and land and the inter-relationship which exists among and between water, air and land, and human beings, other living creatures, plants, micro-organisms and property
Natural and built environment: natural features such as air and water, and human-made features such as cities
Biotic environment: living things, including plants, animals and microbes
Abiotic environment: non-living factors such as light, temperature, water, soil and minerals
Social environment: culture, economy and institutions of people
Biosphere: the global zone of life that includes all ecosystems
Ecosystem boundaries: often set for convenience, such as the edge of a lake
Environmental science: a wider subject that includes pollution, resources, policy and society along with ecology

What Else Should You Remember?

Ecosphere and biosphere: the whole planet’s life and its processes
Microenvironment: the local conditions around a small organism
Macroenvironment: the larger region and climate
Internal environment: the body fluids that cells live in, kept stable by homeostasis
Man-made ecosystems: farms, reservoirs and cities
Natural ecosystems: forest, grassland, desert and ocean
Terrestrial and aquatic: two broad classes of ecosystem
Ecosystem services: benefits that people get from ecosystems
Environmental factors: climatic, edaphic, topographic and biotic
Constitutional provisions: Article 48A directs the State to protect and improve the environment, and Article 51A(g) makes it a duty of citizens
Ecology in policy: ecological studies inform environmental clearance
World Environment Day: 5 June, started after the Stockholm Conference of 1972
Environment Protection Act year: passed in 1986 after the Bhopal gas tragedy of 1984
Stockholm Declaration: 1972, the first UN conference on human environment
Sustainable development: Brundtland Report, 1987
Ecosystem health: capacity of an ecosystem to function and recover
Link: next topics begin with Definition, Functions and Properties of an Ecosystem
Environment definitions elsewhere: the Water Act of 1974 and Air Act of 1981 use separate definitions of pollution
Components of environment: physical, chemical, biological, social and cultural
Hierarchy: ecosystems sit within the biosphere and form the environment of the organisms living in them
Sample use: a question may ask which of the terms is a functional unit: the answer is ecosystem
Ecosystem examples: pond, forest, grassland, desert, cropland and city
Closed and open: ecosystems are open systems exchanging energy and matter with surroundings
Why the difference matters: a policy for the environment covers pollution and resources, while ecology gives the scientific base, and ecosystem management works on specific units
Ecosystem approach in law: the Convention on Biological Diversity promotes the ecosystem approach
Human environment: includes health, housing and livelihoods

Why Does It Matter for the Exam?

Definitions: science, surroundings, unit
Coined by: Haeckel and Tansley
Law: 1986 Act definition
Current affairs link: ecosystem restoration decade
Common errors: calling ecology a place or an ecosystem a science

As an analytical point, ecology gives the knowledge, the environment gives the conditions and the ecosystem gives the functioning unit. Clear use of these terms helps in writing precise answers and in framing environmental law.

Why Is This Topic Important?

Ecology Science
Environment Surroundings
Ecosystem Unit

What Came Next?

The next macro covers ecosystem structure and function, beginning with the definition and properties of an ecosystem. Next topic: Definition, Functions and Properties of an Ecosystem.

Key People and Terms

Ecology Study of relationships
Environment All surroundings
Ecosystem Functional unit
Abiotic Non-living
Biotic Living
Biosphere Global life zone

Exam Corner

Points to Remember

Ecology: 1866, Haeckel.
Ecosystem: 1935, Tansley.
Environment Protection Act: 1986.
Article 48A and 51A(g).
World Environment Day: 5 June.

Do Not Confuse With

Ecology and ecosystem Study versus the system studied
Environment and ecosystem Surroundings versus functioning unit
Ecology and environmental science Natural science versus broader field

Memory Hook

Ecology studies, environment surrounds, ecosystem works.

Mains Angle

Questions ask for definitions and differences. These points help.

Terms Three
Law 1986 Act
Link Policy

A Question You May Face

An original practice question, not a past paper question.

“Differentiate between ecology, environment and ecosystem, and state how the Environment Protection Act, 1986 defines the environment.”

How to Answer

Define Three terms.
Compare Table.
Law 1986 Act.
Example Forest.

GS Relevance

Prelims: definitions, differences, legal definition of environment. GS Paper 3: environment basics.

Frequently Asked Questions

What is the difference between ecology and environment?

Ecology is the scientific study of the relationships between organisms and their surroundings, while environment is the sum of all the living and non-living things and conditions around an organism. Ecology is a subject of study, and environment is the setting that ecology studies.

What is the difference between ecosystem and environment?

An ecosystem is a functional unit made of living organisms and their non-living surroundings that interact through energy flow and nutrient cycling. The environment is simply all the external conditions and surroundings of an organism or a community. An ecosystem includes the organisms, while the environment is defined around them.

How does the Environment Protection Act, 1986 define the environment?

Section 2(a) of the Environment (Protection) Act, 1986 says that environment includes water, air and land and the inter-relationship which exists among and between water, air and land and human beings, other living creatures, plants, micro-organisms and property.

Who coined the terms ecology and ecosystem?

Ernst Haeckel, a German biologist, coined the word ecology in 1866, and the British ecologist A G Tansley coined the word ecosystem in 1935. Haeckel used it for the study of the relations of organisms with their surroundings, and Tansley for the combined system of organisms and their physical environment.

What are abiotic and biotic components of the environment?

Abiotic components are the non-living parts such as light, temperature, water, air, soil and minerals. Biotic components are the living parts such as plants, animals, fungi and microorganisms. Together they form an ecosystem, in which they interact continuously through flows of energy and matter.

PYQ Practice — Statement Analysis

1 Ecology is the study of relations between organisms and their environment.

True

Named by Haeckel.

2 An ecosystem is a branch of science.

False

It is a functional unit of nature.

3 The Environment Protection Act was passed in 1986.