The correct Answer is A
Explanation
Biogeochemical cycles describe the pathways by which chemical elements move through the biotic and abiotic components of the Earth. These cycles are broadly classified into gaseous and sedimentary cycles based on the primary reservoir of the element.
Statement-wise Analysis
- A. Gaseous cycle - 1. Reservoir in atmosphere or hydrosphere
Correct: Gaseous cycles are characterized by their primary reservoir being the atmosphere or the hydrosphere (oceans). Examples include the nitrogen cycle and the water cycle, where large quantities of the element exist in gaseous or liquid forms in these reservoirs.
- B. Sedimentary cycle - 4. Reservoir in Earth’s crust (General)
Correct: Sedimentary cycles have their main reservoir in the Earth's crust. Elements involved in these cycles are typically found in rocks, minerals, and soil. Examples include the phosphorus cycle and the sulfur cycle.
- C. Carbon cycle - 3. Reservoir in atmosphere (e.g., Carbon)
Correct: The carbon cycle is a gaseous cycle where the atmosphere serves as a significant reservoir in the form of carbon dioxide (CO2). Oceans also act as a major reservoir for dissolved carbon.
- D. Phosphorus cycle - 2. Reservoir in Earth’s crust (e.g., Phosphorus)
Correct: The phosphorus cycle is a sedimentary cycle. Its primary reservoir is the Earth's crust, where phosphorus is found in rocks and mineral deposits. There is no significant gaseous phase for phosphorus.
Key Takeaway
Biogeochemical cycles are categorized into gaseous and sedimentary types based on their primary reservoir, with gaseous cycles having atmospheric or hydrospheric reservoirs and sedimentary cycles having lithospheric (Earth's crust) reservoirs.