MEASUREMENTS OF PHOTOSYNTHETIC PHOTON FLUX (PPF) AND FLUX DENSITY (PPFD) FOR GREENHOUSE LED IRRADIATORS

摘要

In global agriculture and, in particular, in Russia the tendency of artificial lighting in greenhouses growth is clearly visible. Until recently most of greenhouses used irradiators with high pressure sodium lamps (HPS lamps). The photometric system of units and relevant meters (illuminance meters) were successful used for plants irradiation measurements. The advent of LED luminaires with different light spectra, including those that emit in the visible spectrum border regions (in blue and red bands), necessitated the introduction of PAR (photosynthetically active radiation) system into practice. This paper discusses the issues related to PAR measurements of PAR values such as PPF and PPFD. Greenhouses artificial lighting and, therefore, the production of environmentally friendly vegetable products is becoming increasingly popular. According to [1], the global market of artificial greenhouses lighting is growing by 5 % - 6 % per year, and this trend will continue at least until 2022 (Fig. 1). Currently, the greenhouse plant production in Russia is at the stage of dynamic development and implementation of new technologies. At the beginning of 2018 the area of heated greenhouses was about 2500 hectares, and we expect that by 2020 there will be about 1000 hectares of modern greenhouses more. Up to 80% of new areas of greenhouses use the photoculture technology (Fig. 2), and the total number of light points in greenhouses is approaching 1.5 millions. The vast majority of greenhouses are equipped with irradiators with HPS lamps.