Elements of Soil Science
Course Objective:
To develop understanding about soil forming processes and soil as natural body/medium for storage and movement of water, gases, heat, nutrients and physical and chemical properties of soil.
- Definition, Concept and Use of Soil (2 hours)
- Soils in relation to agricultural production
- Concepts of land and soil
- Definition and concept of soil science
- Soil Forming Factors, Processes and Classification (12 hours)
- Soil forming rocks and minerals
- Weathering of rocks and minerals
- Soil profile: horizon designations
- Morphological properties
- Factors of soil formation
- Major soil forming processes
- Introduction and history of soil classification
- Surface and sub-surface diagnostic horizons
- Soil temperature regimes
- Soil moisture regimes
- Classification according to soil taxonomy
- FAO/UNESCO system of soil classification
- Soils of Nepal and their suitability for different purposes
- Processes of soil survey and mapping
- Physical Properties of Soils (8 hours)
- Soil color
- Mechanical composition and textural classification
- Soil structure
- Bulk density, particle density and porosity
- Soil consistency
- Soil aeration
- Soil moisture
- Soil heat
- Soil Physical Properties in Relation to Plant Growth (8 hours)
- Soil moisture:
- quantitative concepts and measurements
- energy concepts and measurement
- soil moisture characteristics curves
- soil water movements (saturated and unsaturated)
- infiltration and percolation
- moisture extraction by plant roots
- Soil aeration:
- significance
- composition
- mechanism of renewal
- Soil temperature:
- energy balance
- soil thermal properties
- diurnal and seasonal variations
- significance
- Soil Chemistry and Fertility (15 hours)
- Soil reaction:
- acidic soils
- saline soils
- alkali soils
- soil amendments
- Soil colloids and their properties
- Cation and anion exchange phenomenon
- Macro and secondary plant nutrients:
- forms
- functions
- deficiency symptoms
- transformation
- availability to the plants
- Introduction to micro nutrients and their significance in plant growth
- Inorganic fertilizers:
- composition
- uses
- behavior in soil
- Soil fertility evaluation:
- soil testing
- plant analysis
- deficiency symptoms
- biological tests
- Soil organic matters and organic manures
- Green manuring and biofertilizers
Practical:
- Identification of important rocks and minerals
- Collection and preparation of soil samples
- Determination of soil texture and consistency by feel method
- Identification of soil structure
- Determination of bulk density, particle density, total porosity and air porosity
- Particle size analysis by hydrometer method
- Determination of aggregate size distribution
- Study of soil profile and morphological properties
- Determination of soil moisture content by weight and volume
- Measurement of soil moisture by metric suction
- Measurement of soil moisture by electrical resistance method (use of soil moisture Meter)
- Observation of capillary phenomenon in soil
- Determination of hydraulic conductivity
- Determination of infiltration characteristics of soils
- Use of soil testing kit
- Determination of organic matter in soils
- Determination of soil pH and electrical conductivity
- Estimation of available nitrogen, phosphorous and potassium
- Identification of nutrient deficiency symptoms of major crops
References:
- Nyle C. Brady. The Nature and Properties of Soils. 10th edition. Prentice Hall of India Ltd.
- Biswas T.D. and S.K. Mukharjee. A Textbook of Soil Science. Tata McGraw Hill Publications
- Oswal M.C. Soil Physics. Oxford and IBH Publishing Co. New Delhi
- Gupta. P.K. Soil, Plant , Water and Fertilizer Anlysis. Agrobios (India)
Evaluation system:
The questions will cover all the chapters of the syllabus. The evaluation scheme will be as indicated in the table below:
Chapters |
Hours |
Marks Distribution* |
1 |
2 |
4 |
2 |
12 |
20 |
3 |
8 |
14 |
4 |
8 |
14 |
5 |
15 |
28 |
Total |
45 |
80 |
*Note: There may be minor deviation in marks distribution
|