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Pavlić K., & Andreić Z. (2020). Comparison Of Night Sky Brightness Above Zagreb And A Nearby Rural Location 2014-2017. Rudarsko-geološko-Naftni Zbornik, 35(2), 45–56.
Abstract: The results of monitoring light pollution near the center of Zagreb at the Faculty of Mining, Geology and Petroleum Engineering (RGN) for the period 2012 – 2017 were presented in a recent article (Andreić, 2018). The question that re- mained unanswered is how the night sky brightness behaves in the suburbs of Zagreb and in the nearby rural area. This article attempts to give some answers to this question by analyzing data gathered at the rural site of Merenje, located north of Zagreb. The main conclusion drawn is that the night sky brightness at both sites follows very similar patterns for clear sky conditions and is often similar for cloudy conditions, too. For both sites, no significant increase in zenithal night sky brightness was found in the observed period of 2014 – 2017. Thus, at least for the areas north of Zagreb that are in the shadow of Medvednica Mountain, the contribution of the light pollution from Zagreb and its growing outskirts remains unaltered. The main difference is in the level of the night sky brightness, the average for the RGN site being 16.9 mag/ arcsec2 and 18.9 mag/arcsec2 for the Merenje site. Additionally, the cloudy conditions enhance the light pollution of Za- greb a lot more, the difference being about 3.2 mag/arcsec2 for RGN, in contrast to 1.9 mag/arcsec2 for the Merenje site. No measurements exist for areas to the south, so no conclusions can be made for the situation there. Last, but not least, it was found that in cloudy conditions, the stronger light pollution of Zagreb is proportionally more enhanced by the clouds/fog than the smaller levels of light pollution at the Merenje site.
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Chukwu A. T., Samaila N., & Okrikata E. (2019). Flight to Light Response of Red Pumpkin Beetle (Aulacophora africana Weise) to Differently Coloured Light-emitting Diode and Incandescent Bulb Lights. Adv. J. Grad. Res., 7(1), 64–69.
Abstract: Red pumpkin beetle (Aulacophora africana Weise) is an important defoliator and vector of pathogens to its numerous crop hosts. Control had largely been by synthetic insecticides with their attendant consequences on man and the environment thus necessitating scientific studies on environmental-friendly management strategies. The experiment was conducted in the Research Farm of Federal University Wukari in the month of May 2019 with the aim of evaluating the attractiveness of A. africana to Light-emitting diode (LED) and Incandescent Light bulb colours. Five colours (red, yellow, green, blue and white) were used for the study. Each colour light was properly projected on 2 metre vertical screen (made of white polyethene) placed one meter above the ground. A setup without bulb served as the control. The light traps were arranged in a completely randomized design (CRD) in 6 replicates and ran simultaneously for six hours (1800 to 2400hrs). The pumpkin beetles attracted were collected in tubs containing soapy water. A. africana collected were counted and recorded according to bulb type and colour. Samples were identified at the Insect Museum of Ahmadu Bello University, Zaria. Among the Incandescent bulbs, White colour was most attractive to A. africana (4.30±0.38) while red attracted the least (0.71±0.01). Among LED bulbs, Blue was most attractive (3.99±1.01) while Red also attracted the least (0.78±0.03). Overall, LED attracted more pumpkin beetles than Incandescent bulb even though Student Newman Keul’s test indicates that the difference between them was due to random variation (p = 0.16). Correlation and regression analyses indicated increase in insect attraction with increased light intensity. The results, therefore, suggest that white Incandescent or blue LED bulb colours can be incorporated into insecticidal light traps to suppress their population/attract them away from host plants or fixed into ordinary light traps to harvest the insect for scientific studies.
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Radetsky L., Patel J. S., & Rea M. S. (2020). Continuous and Intermittent Light at Night, Using Red and Blue LEDs to Suppress Basil Downy Mildew Sporulation. HortScience, 55(4), 483–486.
Abstract: Lighting from red and blue light-emitting diodes (LEDs) is common for crop production in controlled environments. Continuous application of red or blue light at night has been shown to suppress sporulation by Peronospora belbahrii, the causal organism of basil downy mildew (DM), but the suppressing effects of intermittent applications of red and blue LEDs have not been thoroughly researched. This study examined the effects of red (λmax = 670 nm) and blue (λmax = 458 nm) LED top lighting, at two photosynthetic photon flux densities (PPFD = ≈12 and ≈60 µmol·m−2·s−1), using continuous (10-hour) nighttime and two intermittent nighttime exposures, to suppress basil DM sporulation. The two intermittent treatments consisted of one 4-hour exposure and three 1.3-hour exposures spaced 3 hours apart. Continuous nighttime treatments with blue or red LED top lighting at ≈60 µmol·m−2·s−1 were able to suppress basil DM sporulation by more than 99%. At a given nighttime dose of light that did not completely suppress sporulation, continuous lighting was more effective than intermittent lighting, and for these partially suppressing doses, red LEDs were not significantly different from blue LEDs for suppressing sporulation. The present study showed that horticultural lighting systems using red and blue LEDs to grow crops during the day can also be used at night to suppress basil DM sporulation by up to 100%.
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Saito, R., Sasaki, H., Yamada, H., Hiroe, Y., Inagake, D., & Saito, T. (2020). Development of a technique to estimate the horizontal distribution of lit fishing vessels in the East China Sea using satellite luminescence. Fish Sci, 86(1), 13–25.
Abstract: The East China Sea is a semi-enclosed sea, surrounded by Japan, China, South Korea and Taiwan, and is continuously influenced by lit fishing vessels overexploiting fishery resources. Quantitative analysis of this fishing activity is essential to sustainable resource management. Recent advances in satellite remote sensing technology, notably the introduction of the Suomi National Polar-orbiting Partnership (Suomi NPP) satellite, which gathers luminescence data, have enabled the detection of lit fishing vessels operating at night. In the present study, we collected in situ observation data (ship radar images and visual observation data for lit fishing gear types) for the period when the Suomi NPP satellite passed over the East China Sea at night. The geographical position of each fishing gear type was extracted from the radar image and compared with the corresponding position of satellite luminescence in order to obtain the luminescence specific to each fishing gear type. We statistically analyzed the luminescence data to specify the luminescence range of each fishing gear type. The luminescence range of Chinese lit falling-net fishing vessels during nighttime fishing operations was distinguished from the ranges of other fishing gear types. We are now able to estimate the horizontal distribution of Chinese lit falling-net fishing vessels from Suomi NPP satellite luminescence, using its own luminescence range.
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Fallows, C., Fallows, M., & Hammerschlag, N. (2016). Effects of lunar phase on predator-prey interactions between white shark (Carcharodon carcharias) and Cape fur seals (Arctocephalus pusillus pusillus). Environ Biol Fish, 99(11), 805–812.
Abstract: Predator-prey relationships can be influenced by environmental conditions, including changes in moon phase and associated lunar illumination. Two primary hypotheses have been proposed underlying the effects of moonlight on predator-prey interactions: the predation risk hypothesis and visual acuity hypothesis. However, few studies have tested these hypotheses during twilight hours or involved large mobile aquatic species. In the present study, we evaluated these hypotheses using data collected over 16 years on predator-prey interactions between white shark (Carcharodon carcharias) and Cape fur seals (Arctocephalus pusillus pusillus) at sunrise. Data from 1476 natural predation events demonstrated shark attack frequency and seal capture success was significantly higher at sunrise during periods of low (0–10 %) versus high (90–100 %) lunar illumination, which is consistent with the visual acuity hypothesis. We propose that during full moon periods, white sharks at night are at a visual and tactical advantage over seals which are silhouetted at the surface in the moonlight and thus easier to isolate in darkness, while sharks remain camouflaged hunting from below through deep water. However, at sunrise, we hypothesize this advantage shifts to seals as the added lunar illumination, combined with emerging sunlight, may decrease shark stealth and increase the ability of seals to detect and avoid sharks. These finding suggest that lunar effects on predator-prey dynamics can be context specific, likely moderated by visual acuity of predators and prey which may change according to the photoperiod.
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