Agriculture Reference
In-Depth Information
Automated Irrigation
Management with Soil
and Canopy Sensing
11
Dong Wang, Susan A. O'Shaughnessy,
and Bradley King
CONTENTS
11.1 Introduction .................................................................................................. 295
11.2 Automation in Pressurized Irrigation Systems............................................. 296
11.2.1 Control Systems ................................................................................ 296
11.2.2 Instrumentation................................................................................. 298
11.2.3 Evapotranspiration Controls .............................................................300
11.3 Automation with Soil Sensing ...................................................................... 301
11.3.1 Soil Water Sensors ............................................................................ 301
11.3.2 Factors Affecting Soil Water Sensing............................................... 303
11.4 Automation with Canopy Sensing ................................................................304
11.4.1 Field-Based Measurement Systems ..................................................304
11.4.2 Sensor Networks ............................................................................... 307
11.5 Automation with SSI..................................................................................... 308
11.5.1 Site-Specific Irrigation...................................................................... 308
11.5.2 Controlling Water Application ......................................................... 309
11.5.3 Control System Hardware................................................................. 310
11.5.4 Control Map...................................................................................... 311
11.5.5 Determining Irrigation System Location ......................................... 312
11.5.6 Current Status of SSI ........................................................................ 313
11.5.7 Site-Specific Chemigation ................................................................ 314
11.6 Summary ...................................................................................................... 315
References .............................................................................................................. 316
11.1 INTRODUCTION
Automated irrigation management refers to the mechanized scheduling of water
delivery based on timing or sensor data. The decision to irrigate is formulated
within an algorithm that is either calendar-based or uses inputs from
in situ
(soil
water sensors) and/or remote sensing measurements (such as canopy temperature
or reflectance). In the case of moving sprinkler systems, data from geographical
positioning sensors are necessary, whereas for drip irrigation systems, the data allow
295
