Environment & Ecology MCQ Questions 2026 – Topic-wise Practice for UPSC, SSC, Forest Services

What is the term used for the process of converting sunlight into chemical energy by plants?

Respiration

Photosynthesis

Decomposition

Fermentation

Easy

💡 Explanation

Photosynthesis is the process by which plants, algae, and some bacteria convert light energy from the sun into chemical energy in the form of organic compounds, such as glucose.

What is the term used for the process of water cycling through the environment?

Water cycle

Hydrologic cycle

Evaporation

Condensation

Easy

💡 Explanation

The hydrologic cycle, also known as the water cycle, is the continuous process by which water is circulated between the Earth's oceans, atmosphere, and land surfaces.

What is the term used for the movement of organisms from one region to another?

Migration

Dispersal

Invasion

Colonization

Easy

💡 Explanation

Migration refers to the seasonal or permanent movement of organisms from one region to another, often in search of food, water, or suitable habitats.

What is the term used for the amount of living matter in a given area?

Biodiversity

Species richness

Species evenness

Biological productivity

Easy

💡 Explanation

Species richness refers to the number of different species present in a given area, which is a key component of biodiversity.

What is the term used for the process of soil erosion caused by wind?

Water erosion

Wind erosion

Soil creep

Soil liquefaction

Easy

💡 Explanation

Wind erosion refers to the process of soil being blown away by wind, which can lead to soil loss and degradation of ecosystems.

What is the term used for the process of plants releasing water vapor into the atmosphere?

Transpiration

Evaporation

Condensation

Precipitation

Easy

💡 Explanation

Transpiration refers to the process by which plants release water vapor into the atmosphere, which is an important component of the water cycle.

What is the term used for the movement of water from the land to the atmosphere?

Runoff

Infiltration

Evaporation

Transpiration

Easy

💡 Explanation

Evaporation refers to the process by which water moves from the land to the atmosphere, often in the form of water vapor.

What is the term used for the process of soil formation through the weathering of rocks?

Soil creep

Soil erosion

Soil formation

Soil liquefaction

Easy

💡 Explanation

Soil formation refers to the process by which soil is created through the weathering of rocks, often over thousands of years.

What is the term used for the amount of waste generated by a given population?

Waste generation

Waste management

Waste disposal

Waste reduction

Easy

💡 Explanation

Waste generation refers to the amount of waste produced by a given population, which can have significant impacts on the environment.

What is the term used for the process of water being stored in underground aquifers?

Groundwater recharge

Groundwater discharge

Surface water runoff

Evaporation

Easy

💡 Explanation

Groundwater recharge refers to the process by which water is stored in underground aquifers, often through infiltration of precipitation or surface water.

What is the term used for the process of plants releasing nutrients into the environment?

Nutrient cycling

Nutrient release

Nutrient uptake

Nutrient storage

Easy

💡 Explanation

Nutrient cycling refers to the process by which plants release nutrients into the environment, often through decomposition or excretion.

What is the term used for the amount of living matter in a given area?

Biodiversity

Species richness

Species evenness

Biological productivity

Easy

💡 Explanation

Biodiversity refers to the total amount of living matter in a given area, including the variety of species, genetic diversity, and ecosystem processes.

What is the term used for the process of soil formation through the addition of organic matter?

Soil creep

Soil erosion

Soil formation

Soil enrichment

Easy

💡 Explanation

Soil enrichment refers to the process by which soil is formed through the addition of organic matter, such as decaying plants and animals.

What is the term used for the process of water being stored in plants?

Transpiration

Evaporation

Condensation

Precipitation

Easy

💡 Explanation

Transpiration refers to the process by which water is stored in plants, often through the absorption of water from the soil.

What is the term used for the amount of waste that is recycled or reused?

Waste reduction

Waste management

Waste disposal

Waste recycling

Easy

💡 Explanation

Waste recycling refers to the process of reusing or recycling waste materials, which can help reduce waste disposal and environmental impacts.

What is the term used for the process of plants releasing oxygen into the atmosphere?

Photosynthesis

Respiration

Decomposition

Fermentation

Easy

💡 Explanation

Photosynthesis refers to the process by which plants release oxygen into the atmosphere, often through the conversion of sunlight into chemical energy.