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प्रश्न
The organic horizon is generally absent from agricultural soils because tilling, e.g., plowing, buries organic matter. Why is an organic horizon generally absent in desert soils?
उत्तर
Organic horizon is generally absent in deserts because of the low content of organic matter due to scarcity of plant and animal remains or excreta.
संबंधित प्रश्न
Read the given statements and select the correct option.
- Hydrophytes possess aerenchyma to support themselves in water.
- Seeds of Viscum are positively photoblastic as they germinate only in presence of light.
- Hygroscopic water is the only soil water available to roots of plants growing in soil as it is present inside the micropores.
- High temperature reduces use of water and solute absorption by roots.
Read the given statements and select the correct option.
Statement A: Cattle do not graze on weeds of Calotropis.
Statement B: Calotropis have thorns and spines, as a defense against herbivores.
In soil water available for plants is
The plant of this group are adapted to live partly in water and partly above substratum and free from water
A free-living nitrogen-fixing cyanobacterium which can also form a symbiotic association with the water fern Azolla
In a fresh water environment like pond, rooted autotrophs are
Sandy soil is not suitable for cultivation. Explain why?
What is myrmecophily?
What is a seed ball?
What is co-evolution?
Explain Raunkiaer classification in the world’s vegetation based on the temperature.
Explain different types of hydrophytes with examples.
What are the advantages of seed dispersal?
Identify the A, B, C, and D in the given table
| Interaction | Effects on species X | Effects on species Y |
| Mutualism | A | (+) |
| B | (+) | (-) |
| Competition | (-) | C |
| D | (-) | 0 |
Column I represent the size of the soil particles and Column II represents the type of soil components. Which of the following is the correct match for the Column I and Column IL
| Column - I | Column - II | ||
| I) | 0.2 to 2.00 mm | i) | Slit soil |
| II) | Less than 0.002 mm | ii) | Clayey soil |
| III) | 0.002 to 0.02 mm | iii) | Sandy soil |
| IV) | 0.002 to 0.2 mm | iv) | Loamy soil |
What is the soil profile? Explain the characters of different soil horizons.
