Irrigation Systems

TIME REQUIRED: About 50 minutes.

SCIENCE INFORMATION: Irrigation is a process to suplement precipitation by artificial means. It is essential to maintain soil moisture during the growing seasons of plants.

Humans are able to collect, store, and bring water to the land to produce crops and other desirable plants. Whenever plant growing areas receive 20" of precipitation or less (semi-arid), irrigation is necessary to insure continuous plant growth.

The different irrigation systems and their uses are:
1. Flood -- pastures, grassland, alfalfa, and grains
2. Row -- corn, beets, carrots, onions, beans, tomatoes and other row crops
3. Aerial -- alfalfa, corn, wheat and other grains
4. Drip -- flowers and garden vegetables

PURPOSE: The purpose of this activity is to provide learner awareness and experience with a variety of irrigation processes.

OBJECTIVES: The learner will be able to:1. Observe and classify irrigation systems.
2. Infer the need for irrigation systems.
3. Describe the different types of irrigation systems.
4. Construct a model and identify the model by observing the characteristics.
5. Operationally define irrigation.

PROCESS SKILLS: Observing, comparing, variable, classifying, modeling, inferring, operationally, defining and describing.

TEACHER PREPARATION:Provide several magazines for student use. Assemble the materials on a supply table for student access. Students should work as individuals or in pairs. 

WHAT TO USE:    

        
• paper
        
• magazines
        
• pencil
        
• scissors
        
• clay
        
• paste
    

INSTRUCTIONAL STRATEGIES:Engage: Write the word irrigation on the chalkboard and encourage several students to discuss the meaning of the terms. 

Explore: Students will work as individuals or in pairs. They will obsever, identify and describe the characteristics of different irrifation systems and how they are used. Have the students cut out pictures of irrigated land and paste to construction paper to build a model of different types of irrigation. 

Explain: Review the different types of irrigation systems. Provdie closure by discussing the summary questions. 

VOCABULARY:    

        
• dryland farming
        
• row irrigation
        
• irrigation systems
        
• aerial irrigation
        
• flood irrigation
        
• drip irrigation
   

WHAT DID YOU LEARN?
1. What is the purpose of irrigation?
The purpose of irrigation is to supply water to plants during dry periods of plant growth.

2. What are different types of irrigation systems?
The different types of irrigation systems are flood, row or furrow, aerial, and drip.

3. What is the source of irrigation water?
The source of irrigation water is precipitation in the mountains of Colorado. Most of it falls in the winter and early spring. The water is delivered by surface systems or underground water systems.

4. Where does excess irrigation water go?
Excess irrigation water may be stored or returned to a delivery system.

APPLIED LEARNING:
1. What type of crops are irrigated by:
a. dryland systems?
 - Dryland crops are wheat, corn, grasses and other drought resistant plants.

b. flood systems?
 - Flood crops are alfalfa, grasses, and some grains such as wheat, barley and oats.

c. row systems?
 - Row crops are beets, corn, onions, beans, carrots and other vegetables.

d. aerial systems?
 - Aerial irrigation crops are alfalfa, wheat, corn, and other grains.

e. drip systems?
 - Drip plants are flowers and other ornamental plants.

2. What parts of the United States require irrigation systems to grow crops?
 - The arid and semi-arid regions of the mid-west and west require irrigation systems to grow crops.

EXTENSION:
Encourage the students to research how much water it takes to produce different types of food. Have them share their findings with the other students by chart and discussion.