PQS 1 PAR Quantum Sensor0 pages

PQS 1 PAR Quantum Sensor
FOR MEASURING PHOTOSYNTHETICALLY ACTIVE RADIATION
Designed for outdoor and indoor use
Excellent quantum response
Integrated leveling base

Introduction
Light plays a crucial part in plant and crop growth. Absorption of light (mostly by chlorophyll) drives the photosynthesis process whereby
carbon dioxide and water are photo-chemically converted into glucose and oxygen. Light which a plant can use for this process is called
Photosynthetically Active Radiation (PAR). The actual response diers depending on the plant or crop. A standardised PAR spectral
response in the visible light range between 400nm and 700nm wavelength was dened by McCree (1972) such that each photon within
this region is equally absorbed. ‘Blue’ photons of shorter wavelength (higher frequency) have more energy than ‘Red’ photons of longer
wavelength. The amount of PAR is commonly expressed as Photosynthetic Photon Flux Density (PPFD) with a unit of µmol/m²·s.

Applications
In horticulture, to optimise crop timing and quality in greenhouses,

In agriculture measurement of PAR helps to predict growth

a delicate control of light intensity is necessary. In order to achieve

rates and estimate crop yields.

this continuous monitoring of the PAR levels of natural sunlight
and artificial lighting inside the greenhouse is required.

The PQS 1 PAR Quantum Sensor is designed to provide
accurate, continuous measurement of PAR outdoors or

In forestry applications the amount of PAR is a key research

indoors. The rugged construction makes it well protected

parameter. It can be measured above, within and below the forest

from harsh weather conditions around the world and from

canopy to retrieve valuable data on plant physiology and leaf area.

exposure to pesticides.