Irrigation Principles (Theory and Application) is a text book intended for students and instructors in University or higher education for Certificate, Diploma and Degree students in a number of courses such as Irrigation and Drainage, Agricultural Engineering, General Agriculture, Agricultural Education and Extension, Horticulture, Water Resources Engineering, applied irrigation engineering and other allied professions.
The content of the text book has been presented in a lucid style, arranged in coherent sequence that adheres to University and higher education curriculum. This makes the book suitable for relaxed reading. For the calculations, worked examples have been solved in a way of illustration and details are presented. Each chapter is concluded with the examples and review questions for the readers to expound on subject knowledge. For the purpose of improvement, any criticism from students, trainers and practitioners will be thankfully received by the author.
Table of Contents
CHAPTER 1 INTRODUCTION TO IRRIGATION
1.1 Definition
1.2 Irrigation for sustainable food security
1.3 Historical perspective of irrigation
1.4 Total and supplemental irrigation
1.6 Spate irrigation
1.7 Importance of Irrigation
1.8 Advantages and disadvantages of Irrigation
1.9 Developmental aspects of irrigation
1.10 Development of irrigation in Kenya
1.11 Challenges of irrigation development
1.12 Strategies for improved irrigation development
1.13 Role of an Irrigation Engineer
1.14 Irrigation schemes in Kenya
CHAPTER 2 IRRIGATION SYSTEMS PLANNING
2.1 Irrigation systems planning
2.2 Irrigation planning process
2.3 Field water balance-based plan
2.4 Fundamental factors in development of irrigation
2.5.1 Technical and physical factors
2.5.2 Economic factors
2.5.3 Social factors
2.5.4 Other factors
CHAPTER 3 SOIL-PLANT-WATER RELATIONSHIP
3.1 Introduction
3.2 Soil
3.2.3 Physical properties
3.2.4 Soil texture
3.2.5 Soil structure
3.2.6 Depth of soil
3.2.7 Chemical nature of soil
3.3 Soil-water relationship
3.3.1 Three phase diagram
3.3.2 Key parameters of soil in irrigation
3.4 Infiltration
3.5 Factors affecting infiltration
3.6 Infiltration models
3.7 Measurement of infiltration
3.7.1 Double-ring infiltrometers
3.7.2 Demerits of ring-infiltiltrometer
3.7.3 Infiltration indices
CHAPTER 4 IRRIGATION-WATER REQUIREMENTS
4.2 Partitioning of evapo-transpiration
4.4.1 Effective rainfall
4.4.2 Factors affecting effective rainfall
4.4.3 Estimation of effective rainfall
4.6 Gross irrigation requirement
4.7 Estimation of evapotranspiration
4.7.1 Lysimeter experiment
4.7.2 Soil moisture depletion method
4.7.3 Field water balance
4.8 Estimation of ET using empirical models
4.8.1 Blaney-Criddle method
4.8.2 Crop Coefficient (Kc)
4.8.5 Thornwaite method
4.9 Irrigation scheduling
4.9.1 Determination of time to Irrigate
4.9.2 Plant Indicator Methods
4.9.4 Soil Indicator Methods
4.9 Delta (Δ)
4.9 Efficiency of irrigation systems
CHAPTER 5 WATER APPLICATION METHODS
5.1 Introduction to methods of irrigation
5.2 Factors that influence the choice of irrigation method
5.3 Surface Irrigation methods
5.3.1 Surface irrigation process
5.4 Basin irrigation
5.4.1 Suitable crops
5.4.3 Basin Layout
5.4.4 Level basin size based on flow time
5.4.5 Shape and dimensions of bunds
5.4.6 Basin Construction
5.4.7 Water application into irrigating basins
5.4.8 Wetting patterns
5.4.9 Water storage in basins
5.4.10 Maintenance of basins
5.4.11 Advantages of basin irrigation
5.4.12 Disadvantages of basin irrigation
5.5 Border irrigation
5.5.1 Application of border irrigation
5.5.2 Border Layout
5.5.3 Maintenance of border irrigation system
5.5.4 Advantages of border irrigation
5.5.5 Disadvantages of border irrigation
5.6 Furrow irrigation
5.6.2 Evaluation of furrow irrigation system
5.6.3 Advantages of furrow irrigation
5.6.4 Disadvantages of furrow irrigation
5.7 Sprinkler irrigation system
5.7.1 Key Components of sprinkler irrigation system
5.8 Sprinkler layout
5.8.1 General rules for sprinkler system layout
5.8.2 Flow of water in sprinkler irrigation system
5.8.3 Performance of sprinkler irrigation system
5.9 Lateral System Design
5.10 Operation of sprinkler systems
5.11 Maintenance of sprinkler systems
5.12 Types of sprinkler irrigation systems
5.12.1 Based on the portability
5.12.2 Based on spraying pattern
5.12.3 Based on arrangement of spraying
5.13 Advantages of sprinkler irrigation
5.14 Drip irrigation
5.15 GSM based irrigation control system
5.15.1 Structure of the GSM module
5.15.2 Irrigation control system
5.15.3 Advantages of GSM based controlled irrigation
CHAPTER 6 DRAINAGE ENGINEERING
6.1 Drainage engineering
6.2 Effect of excess water on agricultural land
6.3 Benefits of good drainage to agricultural land
6.4 Components of drainage system
6.5 Types of Agricultural land drainage systems
6.5.6 Surface drainage systems
6.5.7 Advantages of surface drainage system
6.5.8 Disadvantages of surface drainage
6.5.9 Design discharge and velocity for surface drainage system
6.5.10 Rational method
6.5.11 Curve number (CN) approach
6.6 Sub-surface drainage systems
6.6.1 Advantages of sub-surface drainage
6.6.2 Disadvantages of sub-surface drainage
6.6.3 Design of Sub-surface drainage system
6.6.4 Assumptions of Hooghoudt function
6.7 Tile drain
6.7.1 Diameter of tile drainage system
6.7.2 Ground water drainage
6.8 Mole drainage
CHAPTER 7 WATER QUALITY IN IRRIGATION
7.1 Salts in Irrigation Water
7.2 Origin of salts
7.3 Accumulation of salts in Soil
7.4 Quality of Irrigation Water
7.5 Method of Irrigation
7.6 Effect of salts on plants
7.7 Determinations of salinity and sodicity
7.7.1 Saline soils
7.7.2 Sodic soils
7.7.3 Saline-sodic soils
7.8 Managing salt-affected soils
7.9 Managing saline soils
7.9.1 Reclaiming saline soils
7.9.2 Controlling salinity with irrigation water
7.9.3 Salt-tolerant plants
CHAPTER 8 IRRIGATION PUMPING SYSTEMS
8.1 Pumps
8.2 Types of pumps
8.3 Principles of operation of selected pumps
8.3 Single acting positive displacement pump
8.3.1 Discharge of a single acting reciprocating pump
8.4 Double-acting reciprocating pump
8.4.1 Discharge of a double-acting reciprocating pump
8.5 Principles of operation of hydraulic ram
8.6 Principle of operation of centrifugal pump
8.7 Pump characteristics
8.7.1 Affinity Laws
8.8 Power and energy requirements of a pump
8.10 Pump performance curves
8.11 Capacity of irrigation pump
8.12 Pump system configuration
8.12.1 Pumps in series
8.12.2 Pumps in parallel
CHAPTER 9 MEASUREMENT OF IRRIGATION WATER
9.1 Importance of water measurement
9.2 Methods of water measurement
9.2.1 Tracer method
9.2.2 Water measurement by volume
9.2.3 Use of float
9.2.4 Velocity area methods
9.2.5 Manning‟s formula
9.2.6 Weirs
9.2.7 Venturi meter
9.2.8 Flow nozzles
9.2.9 Orifice meters
9.2.10 Parshall flumes
CHAPTER 10 IRRIGATION WATER MANAGEMENT
10.1 Introduction
10.2 Importance of irrigation water management
10.3 Optimum use of irrigation water
10.4 Need for optimum use of irrigation water
10.5 Strategies to improve irrigation water management
10.6 Causes of poor irrigation water management
10.7 Conjunctive water use
10.8 Participatory irrigation management (PIM)
10.9 Principles of PIM
CHAPTER 11 ECONOMIC ASPECTS OF IRRIGATION
11.1 Introduction
11.2 Feasibility of irrigation project
11.3 Increase in land value
11.5 Climate
11.6 Crop types
11.7 Water supply
11.8 Cost of irrigation works
11.9 Marketing of agricultural produce
11.10 Security of irrigation project
CHAPTER 12 IRRIGATION SYSTEMS FOR HYDROPONICS
12.1 Introduction to hydroponic system
12.2 Advantages of Hydroponics
12.3 Disadvantages of hydroponics
12.4 Irrigation within hydroponics
12.5 Water quantity
12.6 Water quality
12.7 Root zone environment
12.8 Layout and performance of hydroponic irrigation systems
12.9 Irrigation amount
12.10 Irrigation frequency in hydroponics
12.11 Hydroponics irrigation control
Objectives and Topics
The book aims to provide comprehensive knowledge on the fundamental theories and practical applications of irrigation engineering. It covers key topics such as irrigation systems planning, soil-plant-water relationships, water requirements, various application methods, and sustainable irrigation water management to ensure optimal food production.
- Irrigation planning concepts and system design
- Soil-plant-water relationships and infiltration processes
- Estimation of irrigation water requirements
- Methods of irrigation, including surface, sprinkler, drip, and hydroponic systems
- Economic and management aspects of irrigation projects
Excerpt from the Book
Irrigation Principles (Theory and Application)
Irrigation is a controlled artificial application, conservation and storage of water to plant root zone for the purpose of crop production. Its fundamental objective is to create an optimal soil moisture system for maximizing crop production and quality while at the same time minimizing any environmental degradation inherent in irrigation of agricultural lands.
In the context of this book, Irrigation Engineering is the application of scientific and mathematical principles to practical solutions in design, manufacture, and operation of efficient and economical irrigation structures, machines, systems and processes.
Summary of Chapters
CHAPTER 1 INTRODUCTION TO IRRIGATION: Defines irrigation and irrigation engineering, explores its history and importance for food security, and discusses different irrigation classifications and development challenges.
CHAPTER 2 IRRIGATION SYSTEMS PLANNING: Details the systematic nine-step process for planning irrigation projects, emphasizing the analysis of technical, economic, social, and political factors.
CHAPTER 3 SOIL-PLANT-WATER RELATIONSHIP: Examines how soil acts as a reservoir for water and nutrients, covering soil physical properties, root zone dynamics, and various infiltration models.
CHAPTER 4 IRRIGATION-WATER REQUIREMENTS: Explains how to estimate evapotranspiration and net irrigation needs, including concepts like effective rainfall and the calculation of scheduling intervals.
CHAPTER 5 WATER APPLICATION METHODS: Describes different irrigation techniques such as surface (basin, border, furrow), sprinkler, and drip irrigation, including design considerations and modern automated control systems.
CHAPTER 6 DRAINAGE ENGINEERING: Discusses the necessity of controlling excess water to prevent waterlogging and soil degradation through various surface and sub-surface drainage methods.
CHAPTER 7 WATER QUALITY IN IRRIGATION: Analyzes the composition of salts in water, the management of salinity and sodicity in soils, and strategies for using salt-tolerant crops.
CHAPTER 8 IRRIGATION PUMPING SYSTEMS: Provides an overview of pump types and principles of operation, including performance curves, power requirements, and system configuration for series or parallel operation.
CHAPTER 9 MEASUREMENT OF IRRIGATION WATER: Covers common techniques for measuring water flow, including tracer methods, volumetric measurement, velocity-area approaches, weirs, and venturi meters.
CHAPTER 10 IRRIGATION WATER MANAGEMENT: Focuses on the strategic importance of managing water resources optimally and introduces the principles of Participatory Irrigation Management (PIM).
CHAPTER 11 ECONOMIC ASPECTS OF IRRIGATION: Outlines the economic evaluation of irrigation projects, including feasibility studies, cost-benefit analysis, and engineering economy principles.
CHAPTER 12 IRRIGATION SYSTEMS FOR HYDROPONICS: Discusses the requirements and layout of hydroponic irrigation systems, including irrigation control and oxygen management in the root zone environment.
Keywords
Irrigation engineering, soil-plant-water relationship, evapotranspiration, irrigation scheduling, water quality, drainage engineering, pumping systems, water measurement, hydroponics, crop water requirement, salinity management, surface irrigation, sprinkler irrigation, drip irrigation, irrigation planning.
Frequently Asked Questions
What is the core focus of this book?
The book provides an essential academic and practical foundation for understanding the theoretical principles of irrigation and how they are applied to improve agricultural efficiency and food security.
Which agricultural engineering fields are covered?
It covers a wide range, including irrigation planning, soil science, hydraulic engineering for water measurement and pumping, drainage engineering, and advanced systems like hydroponics.
What are the primary objectives of the work?
The goal is to equip students and practitioners with the skills needed to design, operate, and manage efficient irrigation structures, ensuring that water is utilized effectively to maximize crop yield.
What scientific methods are utilized?
The text employs mathematical and scientific principles to solve problems related to water requirements, drainage design (e.g., Hooghoudt equation), and hydraulics (e.g., Manning’s and Hazen-Williams equations).
What topics are included in the main body?
The main body covers a systematic approach to irrigation starting from planning and site feasibility, moving through soil-plant-water interactions, water application methods, drainage, water quality, pumping systems, and finishing with economic management and hydroponic techniques.
Which keywords define this work?
Key concepts include irrigation engineering, evapotranspiration, soil management, drainage, irrigation scheduling, and hydraulic system design.
How is the 4-3-2-1 rule applied?
The 4-3-2-1 rule describes the percentage of water extraction by plant roots from different quarters of the root zone, helping to identify the optimal zones for water application.
What are the primary differences between series and parallel pump configurations?
Pumps in series are connected to increase the total head when the discharge remains constant, while pumps in parallel are used to combine individual flows and increase the total discharge while the head remains constant.
Why is the "Porous block" sensor important?
It is a cost-effective tool for measuring soil moisture by detecting changes in electrical and thermal conductivity properties as soil moisture content changes.
What does the Hooghoudt equation determine?
It is used in drainage engineering to calculate the required drain spacing in soil to effectively control the groundwater table level.
- Arbeit zitieren
- Raphael Muli Wambua (Autor:in), 2019, Irrigation Principles. Theory and Application, München, GRIN Verlag, https://www.grin.com/document/458531
