Zbigniew W. CZERNIAKOWSKI and Tomasz OLBRYCHT
INFLUENCE OF LIGHT POLLUTION ON ENTHOMOPHAUNA
The dynamic development of urbanized areas and the increasing intensity of their exposure to light pollution may have far-reaching effects on many living organisms. Observations have shown that environmental pollution by artificial light can affect not only the natural reactions of insects to light – phototropism and photoperiodism, but also as a consequence to the disturbance of their occurrence in the natural habitat. It may be dangerous for the species with very high food specialization, that will not find conditions for their development in the urban environment.
Piotr GRONKOWSKI and Marcin WESOŁOWSKI
SUBLIMATION ACTIVITY OF A COMET AND ITS VISIBILITY ON THE NIGHT SKY
The paper presents an analysis of the sublimation activity of a hypothetical comet as a function of its heliocentric distance. The study shows that the change in brightness of the comet for a fixed heliocentric distance depends significantly on the change in the size of this part of the comet nucleus surface, which is sublimation active. The paper also includes the related discussion of visibility of the selected comets depending on the degree of light pollution of the night sky.
COMPARATIVE ANALYSIS OF LED AND OLED LIGHTING PARAMETERS IN THE CONTEXT OF BLUE LIGHT EMMISION
Amount of blue light in spectral radiation is an important aspect of today’s light sources. The article presents analysis of blue light content in spectral flux of LEDs and OLEDs. In fact, decision about light source selection is mostly driven by some additional factor, thus other parameters have been analyzed: luminous efficacy, color rendering index and lifetime.
Elżbieta JANOSIK and Stanisław MARZEC
CHARACTERISTICS OF BLUE LIGHT
Blue light is a component of the sun and many artificial sources’ radiation spectrum. This light has capacity for not only creation of visual impression but also affecting the human organism otherwise. In accordance with scientific reports, the blue light may have effect on biological rhythm, elderly persons condition, treatment of skin diseases. But its capacity for retina’s injury is recognized in the best way. There are many technological or modern lighting sources at work, domestic and municipal environment, which emit blue light. We can therefore say that blue light is a common existing factor and unexpectedly may pose a threat to human health. In this article, the review of literature and media information about blue light are reported, to acquaint the society with this subject.
DISORDERS OF BIOLOGICAL RHYTHMS RESULTING FROM LIGHT POLLUTION – SELECTED PHYSIOLOGICAL ASPECTS OF MELATONIN AND VITAMIN D DEFICIENCY
The increase in time of exposure to artificial lighting affects physiological processes in animals and humans. Changes in physiological rhythms result mainly from malfunction of the master clock, located in humans in the nucleus suprachiasmaticus of the anterior hypothalamus, and in consequence – from reduction of melatonin amount produced in the pineal gland and secreted into the circulation only in the dark. That hormone regulates a number of body functions, and its deficiency in the conditions of increased exposure to light is associated, among others, with various forms of cancer, including breast cancer. Anticarcinogenic effects of melatonin are due to its antioxidant, immunomodulatory and antiestrogen properties. Reducing the level of melatonin also interferes with the normal rhythm of sleep and wakefulness, making sleep lighter and increasing the risk of depression. Increased exposure to artificial light, with limited time spent under natural, solar light also causes deficit of calcitriol – vitamin D, whose initial synthesis takes place in the skin due to UV radiation. Vitamin D deficiency may lead to cardiovascular disease and atherosclerosis, increased insulin resistance and diabetes, as well as obesity. In the paper, selected aspects of the physiological mechanisms leading to the development of the above disorders.
LIGHT POLLUTION AND ECOSYSTEMS SERVICES AND HUMAN HEALTH
The publication presents a brief history of artificial light, highlighting its salutary effect on the development of civilization, but also showing the effects of photo-pollution associated with wasting energy and the lack of dissemination of information on the ecological, social and economic consequences of light-duty management. Particular attention has been paid to the potential negative impact of artificial lighting on ecosystem services that rely on biodiversity on Earth, and this is often altered by artificial light.
THE CITY’S LIGHT POLLUTION CREATED BY COLOURED ILLUMINATION
The article touches on issues related to colour lighting which occurs in the urban space. For example in Warsaw colour floodlighting applications was discussed and the legitimacy of the use of colour in individual cases. Reviewed of literature on negative effects of unwanted light on organism. Pointed out on proper planning and modernization of lighting in such as way as to reduce the negative interference of light in the ecosystem.
Agnieszka KRZYMIŃSKA, Małgorzata ŚMIGIELSKA and Roman JUSZCZYK
GROWTH AND FLOWERING OF ALLIUM L. ‘IVORY QUEEN’ FORCING IN ARTIFICIAL LIGHT CONDITION
The purpose of the following study was to determine the influence of the light colour onto the forcing of Allium ‘Ivory Queen’. The bulbs cooling was commenced on the 18th of October 2007. After 11.5 weeks the bulbs were planted into pots and the cooling continued. Joint cooling time was 20 weeks. The plants were transferred to the growth room on the 6th March 2008 and were placed on the shelves under the white, blue, green, yellow and red colour light for 6 or 12 hours a day. The quantum irradiance was 12,5 μmol.m-2.s-1. The obtained results indicate that Allium ‘Ivory Queen’ can be forced in pots under the blue light for 12 hours a day.
THE IMPORTANCE OF APPROPRIATE LIGHTING IN DIFFERENT POPULATIONS – THE ELDERS
The use of a proper artificial light source with the safe for the human’s eye spectrum, may support overcoming the limitations of an aging eye, where reduced amount of light reaches the retina. The most important synchronizer of circadian rhythms: the light-dark changes plays the key role for older adults. The light-dark changes plays an important part in many crucial functions of human organisms: they maintain our body rhythms with the 24-hr solar day, improve sleep quality, reduce sleepiness and fatigue level, increase postural stability and reduce falls risk, improve cognitive functions and reduce aggression risks. The preparation of appropriate artificial light source for older adults is an essential issue for the Polish and other populations, where the amount of older people increases rapidly in nowadays.
SLEEP DISORDERS RELATED TO THE EXPOSURE ON ARTIFICIAL LIGHT IN THE NIGHT
Artificial light disturbing period of nocturnal darkness has a negative impact on sleep. A particularly devastating impact on the natural rhythm of sleep and wakefulness is an evening illumination with the blue light. One of the causes of these disorders is blocking the secretion of melatonin, which supports the normal course of sleep. Inadequate lighting of living areas causes a significant increase in sleep onset latency and the latency of stage 2nd and 3rd of NREM sleep. After the evening 2-hour blue light application the power density of the EEG slow waves in deep sleep and the power of the waves of 2-4 Hz were reduced in the first cycle of sleep. Sleeping in an illuminated bedroom leads to the shallow sleep, too. Regular delay of sleep onset caused by an improper lighting and a lower depth of sleep reduces the amount of nightlong sleep and is one of the types of sleep deprivation, the consequences of which shall be borne by the whole body.
Marta PISAREK, Marta GARGAŁA-POLAR and Tomasz DUDEK
ASTRO TOURISM – IN INTEREST OF CHOSEN INHABITANTS OF PODKARPACIE
The survey research made in 2015 among the selected inhabitants of Podkarpacie was to determine the degree of interest in the astro tourism offer and problems related to pollution of the sky with artificial light. Based on the data obtained it should be stated that these issues are little known to them. A small percentage of the respondents was interested in astronomy and looked for information on authorized websites. Only one in six respondents plan in the near future to participate in the attractions offered by astro-tourism even at a considerable distance and at the price of a one-off ticket over 20 zlotys. In Podkarpackie astro tourism attractions are mainly located in the southern part of the voivodship and concern shows in observatories and Sky Park in the Bieszczady Mountains.
LIGHT TRESPASS INTO FLOODLIT BUILDINGS IN RELATION TO THE REQUIREMENTS OF THE POLISH STANDARD
The main aim of this paper is to define the quantitative nature of a new parameter which is called penetrating luminous flux. It is made by the measurement of illuminance on the windows of an actual floodlit object. Additionally, the results of field measurements and simple computer simulations are compared with the valid requirements of the Polish standard connected with light trespass and the light pollution. The results are also carefully commented upon from the point of view of the lighting designer. The object which forms the basis of the analysis in this paper is the Centre for Foreign Mission Veterans in Warsaw
NIGHT SHIFT WORK – DOES IT MEAN LIGHT POLLUTION AS WELL?
Light pollution denotes an excessive presence of the artificial lighting, particularly at night (ALAN). Since the electricity introduction people started to be active all-round the 24-hs period. However, human physiology is adapted to the regular sequence day/night with the activity during the day and the nocturnal relax and sleep. Diurnal organization of the physiological processes is controlled and synchronized by the endogenous molecular mechanism known as a biological clock with a master structure located within the hypothalamic suprachiasmatic nuclei (SCN). Information about the external lighting conditions is relayed from the special retinal receptors via SCN to the pineal gland synthesizing melatonin, a hormone of darkness. ALAN from various sources, including night shift work and/or electronic devices, evokes misalignment of the endogenous clock and physiology desynchronization. These circumstances are resulting in several civilization-related illnesses, including some cancer types, depression, and metabolic and sleep disorders.
PROPAGATION OF AN ARTIFICIAL LIGHTING IN THE ATMOSPHERE
The work discussed the problem of propagation of light originating from ground light sources. Such light impacts on the environment both directly as well as indirectly by dispersing on the atmospheric aerosols, contributing to the so-called artificial airglow. Such effect is especially important in the case of protected areas located in the vicinity of human settlements, which are the strong sources of light pollution. Extinction of light in the atmosphere, as well as terrain or vegetation causes that at a distance just a few kilometres from light source its direct impact on the environment is negligible. In case of an artificial airglow, the situation is more complex. The analysis of the measurement data collected within a few years has shown that artificial airglow is ecologically important only in the case of overcast sky and that the important factor is the cloud base. It seems that with the low clouds this effect is practically limited to the part of celestial sphere located directly above the light source and disappears very quickly with increasing distance. In case of a cloudless sky or with high clouds, the area of the lighted part of the sky is growing, but the contribution of light pollution in its surface brightness decreases significantly. This means that while the artificial airglow of the cloudless sky is an important problem in astronomical observations, it has a rather negligible ecological impact. The described analysis points to the need of protection of the near vicinity of protected areas first of all from defectively constructed ground lighting. It also indicates the possibility of preserving ecologically dark sky even in the vicinity of large urban centres. At the same time it confirms the necessity of location of astronomical observatories away from any human settlements.
Przemysław TABAKA and Irena FRYC
THE IMPACT OF GROUND REFLECTANCE ON RELATIVE VALUES OF LIGHT POLLUTION CREATED BY OUTDOOR LAMP
The article contains the research results on light pollution relative values. The effect of used luminaire type was analyzed and the kind of ground on which the lamp was installed. Calculations were performed by using professional computer-aided lighting design software DIALux. A number of typical outdoor lighting fixtures were taken into account. These lamps were placed on a grass, soil, concrete, asphalt and snow ground. It was assumed that these luminaires emit the same value of luminous flux. It has been shown that the degree of light pollutions dependent not only on the intensity curve of given luminaire but also on the reflective properties of the ground under the lamp.
Agnieszka WOLSKA and Dariusz SAWICKI
THE BRIGHT AND DARK SIDES OF BLUE LIGHT
In the spectrum of visual radiation the blue light covers the range from about 440 nm to about 490 nm. The scientific reports about significant importance of blue light in human chronobiology, photosynthesis of plants and human health have been published since about 2000. It was demonstrated that blue light could influence human health both positively (sleep and circadian rhythm disorders treatment, enhancement of psychophysical performance and vigilance) and negatively (potential photochemical retinal injury, hormone dependent cancers development). The article presents selected aspects of blue light effects on human body as well as positive and negative results of exposure to that light.
Anita WOŹNY and Dominika RYMARZ
LEDS APPLICATION IN ROOTING OF CHRYSANTHEMUM
Supplementary lighting is commonly used to increase yield and quality of ornamental plants. Light – emitting diodes (LEDs) represent a promising technology for the greenhouse industry that has technical advantages over traditional sodium lamps. In the production of chrysanthemums it is particularly important to have properly developed and well-rooted cuttings. In year – round controlled cultivation of chrysanthemums it is necessary to use supplementary lighting from November to mid-February. The possibility of application of LED during the rooting of two cultivars of chrysanthemums was investigated. Our data suggest that LEDs are suitable replacements for HPS lamps as supplemental light sources during the cuttings rooting. Lower energy consumption compared to conventional sodium lamps will increase the profitability of year – round controlled production of chrysanthemums.
LED OUTDOOR ADVERTISING – NEW TECHNOLOGY AND NEW HAZARDS
The use of LED technology in outdoor advertising has opened up new possibilities impact on the psyche of the potential recipient. However a way of presenting advertising content leaves much to be desired, especially, after dark, when the luminance in the environment of these objects are several times lower than the luminance of the surface screens. The article presents the basic technological solutions for displaying images on LED screens, showing the attractiveness of this type of media, from the point of view of the owners, identified key risks for drivers and discussed nuisance to people living near such billboards.
‘REACH THE SKY’ ERASMUS + PROJECT
Public awareness of the risks arising from broadly defined light pollution is low. Numerous actions taken by ILO as well as its partner schools show how you can take care of the starry sky in every environment. ‘Reach the Sky’ project was very successful which can be attributed to the great interest of our students in physics, geography, natural science and astronomy. Desired results are also achieved due to the fact that astronomy was introduced into the ILO’s curriculum as an extracurricular subject taught. The great interest and engagement of students in astronomy classes as well as in ‘Reach the Sky’ project show that the subject is really necessary in schools.