Loading Events

College of Agriculture and Life Sciences Calendar

Substrate Conditioning Influences Water Capture Efficiency

  • This event has passed.
April 30 @ 9:00 am - 10:00 am

Event Navigation

Substrate Conditioning Influences Water Capture Efficiency of Common Greenhouse Substrate Components
Brian Schulker, MS Seminar
Under the direction of Dr. Brian Jackson
Thursday, April 30, 2020, 9:00 am
Join Zoom Meeting: https://ncsu.zoom.us/j/97791309557?pwd=TnhydWNiVDgrTkpRbjFMdUZHZFZCUT09
Meeting ID: 977 9130 9557; One tap mobile: 646 518 9805 US (New York)

The dynamics of water use in horticultural substrates is a determining factor in the efficacy of an irrigation technique. Substrates are engineered to have different characteristics with individual factors that influence the wettability of each. Reduced substrate wettability can lead to lower substrate water capture, excessive leachate, and poor plant growth. Matching substrate characteristics with irrigation techniques can reduce overall water use and increase system efficiency.

Subirrigation techniques rely on capillary action to transport and capture water within the substrate, while surface irrigation techniques are a combination of infiltration and percolation into the substrate through gravitational potential. Coconut coir, sphagnum peatmoss, and pine bark were tested for water capture efficiency and water capture rate (CR) based on two irrigation techniques and three preconditioned mass wetness’ of 0.5w, 1.0 w, and 2.0w. Coir, the inherently hydrophilic material, demonstrated the greatest ability for water capture across all moisture levels. Conversely, at lower moisture levels peat exhibited difficulty in capturing and retaining water through subirrigation. Pine bark split the difference between peat and coir under drier conditions.
Across all substrates, water capture efficiency decreased as moisture levels decreased. Notably, surface application of water represented the highest water capture efficiency and CR for all three substrates, demonstrating the benefits of gravimetric flow, even in low moisture conditions.


Rachel McLaughlin