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UPPCS Environment Gap Sheet: Ecology Basics.
UPPCS has asked 15 of these. 8 have not been asked yet. Lock the first list, then read the second: it holds what UPPCS has not used yet.
First, the concept
Energy flows one way through an ecosystem, from the Sun to producers to consumers, and is lost as heat at each step. Nutrients go round in cycles.
Only about 10 percent of the energy passes from one level to the next (Lindeman's 10 percent law). That is why food chains are short and the pyramid of energy is never upside down.
UPPCS asks the definitions and the exceptions: which pyramid can be inverted, which species is the pioneer, what an ecotone is.
✅ Already asked (15)
Words and their makers
- Ecosystem (Tansley, 1935) · The term was coined by A. G. Tansley
- Ecology (Haeckel) · The word was coined by Ernst Haeckel (1869)
- Ecological niche · The role and position of a species in its habitat
- Biome · A large region with its own climate, plants and animals: desert, tundra, rain forest
Food chains and pyramids
- Grazing and detritus food chains · Grazing starts from green plants; detritus starts from dead matter
- 10 percent law · Lindeman (1942); energy passed to the next level
- Pyramid of biomass · Inverted in the sea (phytoplankton weigh less than the fish)
- Primary productivity · Gross is all food made by plants; net is what is left after their own respiration
Change over time
- Ecological succession · Slow, orderly change in a community till it reaches a stable climax
- Pioneer species · First to settle on bare rock: lichens
- Climax community · The final, stable stage of succession
Edges, species roles and limits
- Ecotone · The meeting zone of two ecosystems, like a mangrove between land and sea
- Indicator species · Shows the health of the environment: lichens for sulphur dioxide
- Biomagnification · A poison like DDT or mercury grows stronger up the food chain
- Ecological footprint and Earth Overshoot Day · The land and sea a person needs; the day each year we use up a year's resources
❌ Not asked yet (8)
Items marked 'asked in other exams' have come in UPSC or other state exams, not yet in UPPCS.
🔒 8 items not asked yet
Food chains and pyramids: 3 · Change over time: 1 · Edges, species roles and limits: 4
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⚠️ The pyramid of energy is never inverted; the pyramids of numbers and biomass can be. Lichens are the pioneers on rock, not mosses.
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