Measuring turfgrass canopy interception and throughfall using co-located pluviometers

Area of Science:

• Horticultural Science
• Environmental Science
• Water Management

Background:

• Turfgrass management frequently involves watering, yet irrigation strategies often overlook canopy interception.
• Canopy interception is the process where water evaporates from plant surfaces before reaching the soil.

Purpose of the Study:

• Quantify precipitation interception and throughfall in 'Meyer' zoysiagrass and '007' creeping bentgrass.
• Evaluate the impact of canopy interception on water reaching the soil surface.

Main Methods:

• Utilized co-located pluviometers with and without turfgrass patches to measure interception and throughfall.
• Collected data from 15 storms and 25 rainfall events, with precipitation ranging from 0.3 mm to 42.4 mm.

Main Results:

• A strong positive linear relationship (r = 0.98) was observed between throughfall amount and precipitation totals.
• Zoysiagrass and creeping bentgrass canopies intercepted an average of 4.4 mm before throughfall.
• Post-throughfall, 16% of additional precipitation/irrigation was lost to interception.

Conclusions:

• No precipitation reaches the soil surface for events under 4.4 mm on average.
• Canopy interception significantly impacts water availability in turfgrass systems, especially in regions like the contiguous U.S.
• Small precipitation and irrigation events are inefficient for turfgrass due to substantial interception losses.