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What is the objective of soil classification?

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Ans: Objectives of soil classification are as follows: 1) Classification helps to group soils that have similar properties. Soils behavior can be estimated based on experience gained from similar group soil. 2) It facilitate communication. It provides common language between engineers dealing with soil. 3) It provides a really convenient shorthand notation. Just providing a little symbol can pack a whole lot of information.

Similar question like above that can be asked. What are the requirements for soil classification system to be useful for Geotechnical Engineering? Ans: Requirements for soil classification system are: 1) It should have a limited number of groups. 2) It should be based on the engineering properties that are most relevant for the purpose for which the classification has been made. 3) It should be simple and should use the terms that are easily understood.

Discuss about propagation methods in bioengineering.

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Ans: Plant propagation is the process of creating new plants from a variety of sources: seeds, cuttings and other plants. Several propagation methods can be used according to our requirements. For example, Perennial grasses usually form the main part of a bioengineering scheme. Seed is a cheap means of propagating these grasses, but requires much longer growing in the nursery before the plants can be used on site. Grasses from cuttings always grow much faster than those produced from seed. Also, they are tougher and do not go through such a delicate stage as seedlings. Propagation method further provide us with best options for sowing according to plant species. Such as, Polypot seedling ( Plants are raised from seed in a nursery. They are grown on in polythene containers 'polypots') propagation method is mainly applied for plants like chilaune, gobre salla, kalo siris, khayer, painyu, khote salla, rato siris, seto siris and utis. Similarly Hardwood cutting ( a section of woody stem is cut from parent plant and inserted into soil) is suitable for Assuro, kanda phul, namdi phul and simal. And stump cutting ( 'Stumps' are cuttings consisting of sections of the plant that include both root and shoot.) method is mainly applied for utis. Some propagation method such as

budding and grafting can combine different plants for specific properties. Such as one plant can contribute better root stock to plant where as an other plant can serve as a fodder plant for livestock.

Sometime if propagation method is asked for large marks. Propagation method Slip cutting

Stem cutting

Seeds

Propagation method Polypot seedling Hardwood cutting Stump cuttings Budding and Grafting

Propagation method Traditional method

Rooted single node culm cutting

Propagation method for grass Description The main method of propagating grasses for bio-engineering. Rooted cuttings are made by splitting out grass clumps grown in the nursery. If the grass is rhizomatous (like amliso or tite nigalo), then the slip consists of a section of the rhizome and some shoots, and must include root buds Propagation by planting a section of the stem, usually with 2 nodes and a section of culm. This is carried out either in the nursery for transplanting as rooted cutting or directly on the site. Grass plants are grown up from seeds. This is carried out either in the nursery for transplanting as a rooted plant, or directly on site. Propagation method for shurbs and trees

Main species All bio-engineering grass species

Napier, Narkat

Babiyo, Khar, phurke,sito

Description Main species Plants are raised from seeds in nursery. They are grown in polythene container Chilaunay, gobre salla, kalo siris, Khayer, (polypot), and also moved in them to site for final transplanting. painyu,utis A section of woody stem is cut from parent plant and inserted into soil. From the buds on the cutting, shoots and roots develop to form new plant. Assuro, Kanda phul, namdi phul, simal Stumps are cutting consisting of section of plant that include both root and shoot. Sisau They are made from seedling more than one year old raised in soil beds. Budding and grafting can combine different plants for specific properties. Such as one plant can provide better root stock where as other plant can serve as fodder plant for live stock Not normally used in bioengineering. Propagation method for Bamboos Description Main species A section of rooted rhizome and an entire culm is cut out of an established All bamboos bamboo clump. It is replanted with the culm cut off about 2m above the ground, leaving branches emerging from one or two of the nodes. Single node of a bamboo culm is planted in a wet, well-shaded nursery bed and choya/tama, dhanu or kalo bans allowed to root over a period of atleast one year. It is then transported for planting on site as a newly rooted plant.