HS917: Drip Irrigation: The BMP Era - An Integrated Approach to Water and Fertilizer Management for Vegetables Grown with Plasticulture
Figure 4. Soluble blue dye may be used to visualize wetting patterns and understand how irrigation volume affects water movement in the bed. For short irrigation times (1 hour) a more even water distribution pattern may be expected with a 4-in emitter spacing (4.1) than with an 12-in emitter spacing (4.2). Flow rates were 33 gal/100 ft/hr for the 4-in emitter spacing, and 30 gal/100ft/hr for the 12-in emitter spacing. The presence of an impermeable clay layer at the 10-in depth (in Gadsden county) resulted in lateral movement as shown in (4.3) where the blue dye is in the alley (between the 3rd and 4th bed from the right) after 6 hours of irrigation delivering 180 gal/100ft. The presence of water and soluble nutrients in the row middles will likely promote weed growth. Wetting patterns in the very compacted beds used for strawberry production in Hillsborough county are rectangular which corresponds to an increase in lateral water movement as shown in (4.4) after a 6-hr irrigation that delivered 144 gal/100 ft with a 12-in emitter spacing.
