UPSC CSE · Environment and Ecology
UPSC Prelims Ecology and Ecosystem Questions (Environment and Ecology): PYQs with Answers
30 UPSC Prelims questions on Ecology and Ecosystem (Environment and Ecology) from 2011–2026, newest first. 2013 had the most (7). Difficulty: 30% easy, 43% medium and 27% hard.
- Mangrove Climate ResilienceWhich of the following best explain(s) the rationale for protecting mangrove ecosystems in the context of climate resilience?
- Rainforest vs Ocean OxygenWith reference to the planet Earth, consider the following statements:
- Fig Wasp CoevolutionWhich one of the following shows a unique relationship with an insect that has coevolved with it and that is the only insect that can pollinate this tree?
- Largest Tropical PeatlandOne of the following regions has the world's largest tropical peatland, which holds about three years worth of global carbon emissions from fossil fuels; and the…
- Parasitoid SpeciesConsider the following:
- Wetlands Kidneys of Earth"If rainforests and tropical forests are the lungs of the Earth, then surely wetlands function as its kidneys." Which one of the following functions of wetlands best…
- Nitrogen Fixing PlantsWhich of the following are nitrogen-fixing plants?
- Primary Producers OceansConsider the following kinds of organisms:
- Phosphorus CycleIn case of which one of the following biogeochemical cycles, the weathering of rocks is the main source of release of nutrient to enter the cycle?
- Detritivores OrganismsWhich of the following are detritivores?
- Symbiotic RelationshipsWhich of the following have species that can establish symbiotic relationship with other organisms?
- Savannah VegetationThe vegetation of savannah consists of grassland with scattered small trees, but extensive areas have no trees. The forest development in such areas is generally kept…
- Biological Oxygen DemandBiological Oxygen Demand (BOD) is a standard criterion for
- Butterfly Population DeclineDue to some reasons, if there is a huge fall in the population of butterflies, what could be its likely consequence/consequences?
- Gadgil Kasturirangan Western Ghats‘Gadgil Committee Report’ and ‘Kasturirangan Committee Report’, sometimes seen in the news, are related to
- Ecosystem DefinitionWhich one of the following is the best description of the term 'ecosystem'?
- Food Chain SequenceWhich one of the following is the correct sequence of a food chain?
- Montreux RecordIf a wetland of international importance is brought under the 'Montreux Record', what does it imply?
- Carbon Dioxide Sources CycleWhich of the following adds/add carbon dioxide to the carbon cycle on the planet Earth?
- Decomposers Food ChainWith reference to food chains in ecosystems, which of the following organisms are known as decomposers?
- Grassland Succession FireIn the grasslands, trees do not replace the grasses as a part of an ecological succession because of:
- Ecosystem Productivity RankingWhich one of the following is the correct sequence of ecosystems in the order of decreasing productivity?
- Food Chain DefinitionWith reference to food chains in ecosystems, consider the following statements:
- Biofertilizer Organisms NostocConsider the following organisms: 1. Agaricus 2. Nostoc 3. Spirogyra
- Soil Nitrogen SourcesWhich of the following adds/add nitrogen to the soil?
- Ecological NicheWhich one of the following terms describes not only the physical space occupied by an organism, but also its functional role in the community of organisms?
- Ecosystem Services Millennium AssessmentThe Millennium Ecosystem Assessment describes the following major categories of ecosystem services—provisioning, supporting, regulating, preserving and cultural. Which…
- Phytoplankton Destruction EffectsWhat would happen if phytoplankton of an ocean is completely destroyed for some reason?
- Marine Upwelling ProductivityIn the context of ecosystem productivity, marine upwelling zones are important as they increase the marine productivity by bringing the
- Rain Forest Slow RegenerationIf a tropical rain forest is removed, it does not regenerate quickly as compared to a tropical deciduous forest. This is because