Irrigation Management (Agricultural)

Lesson Structure

There are 8 lessons in this course:

1. Water Management
   • Human water relationship
   • Water and plant growth
   • Xeriscaping
   • Types of water wastage
   • Waste water treatments using reed beds
   • Suitable plants
2. Irrigation Scheduling
   • Considering climate factors for irrigation scheduling
   • Microclimate
   • Equipment used for monitoring water
   • Measuring water usage
   • Measuring soil moisture
3. Drainage
   • Types of drains
   • Layout of drains
   • Improving permeability during construction
   • Improving surface drainage after construction
   • Contingencies to deal with flood
4. Irrigation Controllers
   • Operating Irrigation Controllers
   • Types of controllers
   • Water volume and duration
   • Pumps and pressure systems
   • Pimping mechanism
5. Irrigation Maintenance
   • Maintaining watering system
   • Maintenance procedure and scheduling
   • Maintaining trickle irrigation
   • Problems of water quality and their remedies
   • Improving water quality from any source
6. Fertigation
   • Advantages and disadvantages of fertigation
   • Fertigation types
   • Fertiliser injectors
   • Application of fertiliser
   • Plant nursey fertiliser injection techniques
7. Design Evaluation
   • Evaluating irrigation designs
   • Surface/flood irrigation
   • Sprinkler irrigation
   • Trickle irrigation
   • Microjet irrigation
8. Irrigation Design
   • Pre planning information for irrigation design
   • Type of systems
   • Underground pipes
   • Drainage

Aims

• Devise ways to optimise water efficiency (ie. minimise wastage), during irrigation of plants.
• Schedule irrigation for a large scale situation such as a large nursery, crop, turf, garden or pasture.
• Analyse the design of different drainage systems
• Formulate procedures to operate irrigation controllers, for appropriate tasks.
• Manage the maintenance of irrigation systems, both small and large scale.
• Manage the fertigation of plants through an irrigation system.
• Evaluate the design of large scale irrigation systems.
• Design an irrigation system, including its drainage.

What You Will Do

• WHAT YOU WILL DO IN THIS COURSE
• Explain different factors which cause water to be wasted including:
• Evaporation
  • Run off
  • Over spray
  • Scheduling
  • Determine where water is wasted, in both the operation and management of a specified irrigation system
  • Determine changes to achieve more efficient water usage, in a specified system.
  • Develop guidelines for determining when to irrigate in a particular situation.
  • Determine through an analysis, when to irrigate on a studied site, by evaluating soil moisture and other characteristics of a site, periodically over two months, and referencing annual rainfall statistics over a period of years.
  • Record in a log book, plant growth and soil moisture for an existing irrigation system operated using two different watering patterns, each for one month, and over two consecutive months.
  • Compare differences in varying the scheduling of a watering system over two months
  • Prepare an irrigation schedule for a specific garden or crop.
  • Develop criteria for designing a specified drainage system.
  • Explain the design criteria for a specified drainage requirement.
  • Devise strategies for dealing with drainage requirements in emergencies, including:
  • extreme weather (eg. hail, storm)
  • burst pipe
  • blocked drains
  • Determine appropriate drainage requirements for a specified situation, and over a specified area, including:
  • Type of drainage required
  • Specifications of drainage required
  • Evaluate the operation of a drainage system, installed under irrigation on a site studied by the learner.
  • Compare four different irrigation controllers with reference to different criteria including:
  • Labour costs
  • Maintenance
  • Reliability
  • Determine appropriate applications for four different types of irrigation controllers
  • Explain the operation of a specific brand of time clock, studied by the learner.
  • Explain the operation of a specified computerised irrigation controller.
  • Develop three different procedures to operate a specific irrigation controller, in order to satisfy three different specified purposes.
  • Determine routine site maintenance requirements for different types of irrigation systems including:
  • spray irrigation
  • micro irrigation
  • surface irrigation
  • flood irrigation
  • Explain routine site maintenance requirements for different types of irrigation systems including:
  • spray irrigation
  • micro irrigation
  • surface irrigation
  • flood irrigation
  • Develop a procedure for maintaining water quality, in a specified irrigation system, at a workplace visited by the learner.
  • Explain water quality maintenance activities required for efficient irrigation practices in a specific situation.
  • Compare the service supplied by different irrigation suppliers, in terms of scope and quality.
  • Develop an irrigation monitoring program, for a specific irrigation system, studied by the learner.
  • Write a maintenance schedule for a specified irrigation system.
  • Explain the use of fertigation, in a specific horticultural workplace.
  • Determine appropriate applications for fertigation in one specific industry sector.
  • Determine inappropriate fertigation applications in different specific industry sector.
  • Explain why certain applications for fertigation are inappropriate.
  • Compare the suitability of six different specified fertilisers for fertigation.
  • Determine resources required to undertake fertigation in a specified situation, including:
  • equipment
  • materials
  • manpower
  • Collate available data on a specified irrigation system, including:
  • system performance data
  • water supply
  • water consumption
  • crop production or plant growth data
  • climatic trends
  • soil characteristics
  • monitor irrigation performance
  • Analyse collated data against different criteria including:
  • benchmarks
  • specifications
  • predictions
  • Compile a comprehensive report evaluating a system, which includes:
  • data evaluation
  • performance indicators
  • conclusions
  • recommendations
  • Prepare design specifications for storage and distribution of water.
  • Explain appropriate methods for recycling, re-use or disposal of water, for three different specified irrigation systems.
  • Are there any legal or health considerations?
  • Design a drainage system for a specified irrigation system, including:
  • Sketch plans
  • Materials lists
  • Cost estimates
  • Determine costing for a specified drainage system.
  • Prepare a report recommending design modifications to an existing irrigation system in a specified situation.
  • Prepare a design for a micro irrigation system for an area of forty square metres, to a standard which is adequate for a contractor to install the system; and including:
  • Plans
  • Calculations
  • Materials specifications

WATER RESOURCES ARE PRECIOUS ON A FARM

-So How Do You Optimise their Use?

A certain amount of water will always be misused. That is inevitable. If you understand your land, the climate, your crop or pasture needs, and how water can be wasted; you then have a basis for preventing waste.

1- Evaporation: A certain amount water loss through evaporation is inevitable. Water that is stored in ponds and lakes are more susceptible to evaporation due to large open surface areas. Flood irrigation too, will have more severe evaporation than trickle or drip irrigation. In all cases irrigation that is undertaken at night will suffer less from evaporation losses. Evaporation also takes place through the plants that are being irrigated. This is referred to as transpiration and as a natural process of plants cannot strictly be viewed as water wastage, however it is an important factor in estimating crop irrigation requirements.

• Evaporation - the loss of water as vapour from a free water surface.
• Transpiration - The loss of water as vapour generally through the stomata of leaves.
• Evapotranspiration - Is the combination of the above two factors which is essential when estimating irrigation levels for crops.

The loss of water through evaporation can be controlled either by the type of irrigation employed or by the timing of irrigation practices in relation to local climatic conditions.

2- Seepage: This is another factor which contributes to water loss, which itself, is impossible to check completely. Seepage occurs through the base and walls of canals and dams which are usually constructed from local available soils. The compaction and permeability of these soils are what accounts for the levels of seepage.

3- Runoff: It occurs as a result of too much water, this may be as a result of irrigation or due to excessive rainfall, which in turn may be further intensified by poor drainage. It is the most controllable factor of water wastage but all too often is not given the consideration it deserves. Many variables determine the optimum irrigation rate. These include soil type and quality, climate, soil suction levels (which can be tested using a tensiometre), particular crop requirements, recent watering/rainfall history of the area to be irrigated. Runoff can be reused if the appropriate drainage and recycling techniques have been included into the irrigation design, thus wastage can be minimised.   

4- Overspray: This concerns the use of overhead sprinklers and misters could be included here although this really should not ever be the case. It simply means that too much water has been applied and as a result there is wastage and often the crop growth will be affected as optimum conditions are not in effect.

5- Scheduling: Often in irrigation the water to be used is scheduled. For instance the farmer may have talked to the water bailiff and ordered so many megalitres to be available for a certain day of the week. The water bailiff then releases that amount of water into the river or canal system. There are times however, when the water is not required due to a heavy local rainfall or evaporation rates are markedly less than expected. In this instance the water that is earmarked for the irrigation is not going to aid the crop but more than likely hinder its growth. It will still have to be paid for and will be wasted.

A bailiff may be able to allocate the waste water which you collect to be recycled onto another property; but the main strategy to avoid this scenario is to avoid scheduling until you (the irrigator) are certain of when and how much water you require. This is a good management issue and can be critical in times of uncertain water allocation due to drought.

FREQUENTLY ASKED QUESTIONS

Q. What will these studies lead to?
 
A.  When you understand irrigation, you have an improved capacity to understand all aspects of broad acre water management.
People who have studied irrigation are better equipped to succeed, and that is an advantage in any situation, either as farmer, an farm employee, or working in a farm supply or service business.

 
Q.  Can I get a credit toward a Certificate or Diploma if I wish to continue further studies after this?
 
A.  Yes; both with our schools in Australia and the UK and with a number of affiliated colleges across the world
 

Q. What happens if I have to stop studying for a while? (e.g. Get sick, go on holidays, have a baby).

A. Apply for an extension. It's OK to take a break and start up your study at a later point in time. Just let us know.
 
Q. What level is this course?
 
A.  We designed this course with adults in mind, and with the flexibility to allow students to work to a level that they are comfortable with. People who have a university level education can approach their work in greater depth, and will have the support of an expert to guide and support them. People who have far less experience and education, may work to a lower academic level, and may take longer to complete studies; but with persistence, they will (with help from tutors) still achieve the minimum goals set for the course. This course should not be seen as rigidly being a degree, diploma or certificate level; rather you should simply see it as an opportunity to extend your skills and knowledge in this discipline, starting wherever you currently are, and finishing with a heightened understanding and capacity to work in this field.

 
Q. What do I get as a student?
 
A. First, understand a good course is quite different to a book or a web site

• A course should be something that changes you; making things stick in your mind, improving your capacity to do thing, remember things, solve problems and understand the subject
• A book on this subject is a reference that can be read, but might not be understood as the author intended, and most of which probably will not be remembered unless a lot of time is devoted to studying it.
• A web site is like a book; except there is a stronger likelihood that it could contain biased and even incorrect information.
• An ACS course differs to books, seminars, web sites and other sources of "information" in several key ways.
• It is a constructed learning pathway that is designed with the purpose of bringing about a change in the student
• It is constructed by a team of experts, credible in their field, from across the world (it reflects input from many people, from different countries and climates. (A book more commonly reflects only one).
• Every student is guided as an individual through the learning experience. The learning pathway and the precise information encountered is commonly different for every single student.
• You are monitored; motivated and where necessary your path is corrected as you move through the course. A book is a one way communication (a monologue), whereas a course is two way communication.
• A course filters out and organises information; serving you up a quantity of resources that is "digestible" in a way that is designed to help you digest it.
• ACS provides all essential learning resources (eg. notes or books), and all the tutor support that is needed to successfully complete a course. Some students may choose to buy extra books -but this really is not necessary.
  
  

Q. Will I have problems with practical tasks, because I cannot travel or attend workshops?
 
A. Our college has developed lots of ways of providing for practical learning, that can be done by anyone, anywhere and anytime. Students come from over 150 countries, and the practicals have never been a factor that has stopped someone completing their studies in this course.
All courses include set tasks that add a practical element to the learning experience, but we often give options.
Courses are as far as possible written to cope with the widest range of situations, from people living in Antarctica to someone confined to their home due to illness.
Example -We may ask you to visit a workplace and observe something; but also say or if you have restricted mobility make a virtual visit, on the internet, if possible, or if not, by reviewing a place through an article in a magazine. If you can't find
reference material, ask us and we will send you what you need.
If the course does not provide an option that is achievable, you contact us, and we will give you other options.