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प्रश्न
What is the soil profile? Explain the characters of different soil horizons.
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उत्तर
| Horizon | Description |
| O-Horizon (Organic horizon) Humus SamacheerKalvi.Guru | It consists of fresh or partially decomposed organic matter. 01 - Freshly fallen leaves, twigs, flowers, and fruits. O2 - Dead plants, animals, and their excreta decomposed by micro-organisms. Usually absent in agricultural and deserts. |
| A-Horizon (Leached horizon) Topsoil - Often rich in humus and minerals. | It consists of topsoil with humus, living creatures, and in-organic minerals. A1 - Dark and rich in organic matter because of the mixture of organic and mineral matters. A2 - Light-colored layer with large-sized mineral particles. |
| B-Horizon (Accumulation horizon) (Subsoil - Poor in humus, rich in minerals) | It consists of iron, aluminum, and silica-rich clay organic compounds. |
| C - Horizon (Partially weathered horizon) Weathered rock Fragments - Little or no plant or animal life. | It consists of parent materials of soil, composed of a little amount of organic matter without life forms. |
| R Horizon (Parent material) Bedrock | It is a parent bedrock upon which underground water is found. |
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.
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
Ophrys an orchid resembling the female of an insect so as to able to get pollinated is due to phenomenon of
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
Strong, sharp spines that get attached to animal’s feet are found in the fruits of
Why are some organisms called as eurythermals and some others as stenohaline?
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?
Sandy soil is not suitable for cultivation. Explain why?
What is thermal stratification? Mention their types.
What is a seed ball?
Explain Raunkiaer classification in the world’s vegetation based on the temperature.
What are the advantages of seed dispersal?
Describe the dispersal of fruit and seeds by animals.
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 |
