Daily Light Integral

μmol m 2s 1 or ppfd x 3600 x photoperiod 1 000 000 dli or moles m2 day.

Daily light integral.

Daily light integral referred to as dli is the amount of photosynthetically active radiation par received each day as a function of light intensity and duration. It is a function of photosynthetic light intensity and duration day length and is usually expressed as moles of light mol photons per square meter m 2 per day d 1 or. Dli is an important variable to consider particularly when growing plants in a greenhouse. The formula for calculating dli is.

Mol m 2 d 1. Daily light integral in simple terms is the amount of photosynthetically active radiation par or plant available light that falls on a location in a 24 hour period. The term daily light integral refers to the number of light particles or photons received during one day in a particular location and area. A light emitting ppfd 1000 running 12 hours emits a dli 43 2 moles day computed as 60 sec min 60 min hr 12 hrs day ppfd 1 million current research indicates cannabis grows best at ppfd 1500 dli 65 and temperature 30 degrees c lighting.

Photons that have a wavelength between 400 and 700 nanometers nm provide the energy for photosynthesis which is the process of converting water and carbon dioxide into sugars and oxygen. Daily light integral dli is a measure of the aggregate amount of par light that a surface receives over the course of a day. Light particles particularly those that have a wavelength between 400 and 700 nm provide plants with the energy for photosynthesis. μmol m 2 s 1 and duration day.

These maps were researched and developed by james faust of clemson university and joanne logan of the university of tennessee. It is a very useful metric to determine if a particular location receives sufficient amounts of light for plants to grow well. Daily light integral dli dli ppfd over the course of a light cycle measured as moles of par photons per day example. Ho 238 w measuring daily light integral in a greenhouse purdue extension 2 daily light integral daily light integral dli is the amount of par received each day as a function of light intensity instantaneous light.

Daily light integral dli describes the number of photosynthetically active photons individual particles of light in the 400 700 nm range that are delivered to a specific area 1m2 over a 24 hour period. The daily light integral dli is the number of photosynthetically active photons photons in the par range accumulated in a square meter over the course of a day. Daily light integral dli maps display the ambient light delivered daily during each month across the entire u s. They are unique because dli is a measurement of light that is particularly valuable for estimating plant.

It is expressed as moles of light mol per square meter m 2 per day. It is expressed in terms of moles of light per square meter per day or mol m 2 d 1.