Lesson 2 - Irrigation Engineering Principles Flashcards
Provides a structural base to the plants and allows the root system to spread and get a strong hold.
Soil
A heterogeneous mass consisting of a three phase system of solid, liquid and gas
Soil
A complex mass of mineral and organic particles
Soil
Soil properties
Soil texture
Soil structure
The relative sizes of soil particles in a given soil
Soil texture
Soil particles according to size
Gravel
Sand
Silt
Clay
USDA
United States Department of Agriculture
AASHTO
American Association of State Highway and Transportation Officials
Soil classification
Open or light textural soils
Medium textured soils
Tight or heavy textured soils
Are mainly coarse and sandy with low content of silt and clay
Open or light textural soils
Contains sand, silt and clay
Medium textured soils
Contains high proportion of clay
Tight or heavy textured soils
Refers to the arrangement of soil particles and aggregates with respect to each other
Soil structure
Soil structure
Type
Class
Grade
Four types of primary structure
Platy
Prism-like
Block-like
Spheroidal
Five recognized classes in primary types of soils
Very fine Fine Medium Coarse Very coarse
Represents the degree of aggradation that is the proportion between aggregates and unaggregated material that results when the aggregates are displaced or gently crushed
Grade
Soil group (India)
Alluvial soils Black soils Red soils Laterites and Lateric soils Desert soils Problem soils
Are accumulated sediments transferred by the rivers and rapids
Alluvial soils
Cotton is the most important crop grown in these soils.
Black soils
Has a reddish tinge as a result of the presence of iron compounds in it.
Red soils
Soil and rock type rich in iron and aluminum and is commonly considered to have formed in hot and wet tropical areas
Laterite soils
Are called aridisols (dry soil)
They occur in floodplains after a spring flood
Desert soils
Can affect the stability of the built infrastructure both across a wide area and very locally
Problem soils
Is a form of water which reaches at the soil water table due to the gravitational force after rainfall.
Gravitational water
Water exists between soil particles in a small capillary pores
Capillary water
Thin film of water is tightly held by the soil particles
Hygroscopic water
Importance of water in plant growth
- Water maintains the turgidity of the plant
- Provides both oxygen and hydrogen
- Acts a solvent of plant nutrients
- Food manufactured gets distributed throughout the plants
- Transpiration is vital process in plants when water is adequate
- Dissipate the heat by transpiration
