Which one of the following options represents the steps of decomposition in sequence?
Fragmentation → Leaching → Catabolism → Humification → Mineralization
Decomposition breaks down complex organic detritus into inorganic substances such as CO2, water and nutrients. NCERT lists its important steps in this order: fragmentation, leaching, catabolism, humification and mineralisation.
Step 1 — Fragmentation: detritivores such as earthworms break detritus into smaller particles.
Step 2 — Leaching: water-soluble inorganic nutrients go down into the soil horizon and get precipitated as unavailable salts.
Step 3 — Catabolism: bacterial and fungal enzymes degrade detritus into simpler inorganic substances.
Step 4 — Humification: a dark, amorphous, colloidal substance called humus accumulates; it is highly resistant to microbial action.
Step 5 — Mineralisation: humus is further degraded by some microbes and inorganic nutrients are released.
Sequences that place humification before leaching or catabolism, or leaching after mineralisation, reverse these steps.
Fragmentation → Leaching → Catabolism → Humification → Mineralization option is correct.
Similar Questions
Given below are two statements.
Statement I: There is less species biodiversity in tropical latitudes than in temperate region
Statement II: Tropical environments unlike temperate ones are less seasonal, relatively more constant and predictable.
In the light of the above statements, choose the correct answer from the options given below.
The Annual Net Primary Productivity on land and ocean respectively are ________ and ________ billion tons.
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Identify the correct option representing the status of age pyramids labelled as A, B and C.
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Important Questions from Ecology
- Given below are two statements : one is labelled as Assertion A and the other is labelled as Reason R.
Assertion A : Abingdon tortoise in Galapagos islands became extinct within a decade after goats were introduced.
Reason R : Goats were more efficient at browsing than Abingdon tortoise.
In the light of the above statements, choose the most appropriate answer from the options given below : - Which of the following statements are correct ?
(a) Energy flow from producers to consumers is unidirectional
(b) Energy pyramid can never be inverted
(c) Transfer of energy follows the 1% law
Choose the correct answer from the options given below : - Arrange the following in descending order of number of species in the Amazonian rain forest.
(a) Plants
(b) Birds
(c) Fishes
(d) Invertebrates
(e) Mammals
Choose the correct answer from the options given below : - Match List-I with List-II.
List-I List-II A. Both species are harmed I. Predation B. One species is harmed and the other is benefited II. Mutualism C. Both species are benefited III. Competition D. One is benefited while the other has no effect IV. Commensalism
Choose the correct answer from the options given below : - Which of the following are primary consumers in a food chain ?
