Abstract: Among the many anthropogenic changes that impact humans and wildlife, one of the most pervasive but least understood is light pollution. Although detrimental physiological and behavioural effects resulting from exposure to light at night are widely appreciated, the impacts of light pollution on infectious disease risk have not been studied. Here, we demonstrate that artificial light at night (ALAN) extends the infectious-to-vector period of the house sparrow (Passer domesticus), an urban-dwelling avian reservoir host of West Nile virus (WNV). Sparrows exposed to ALAN maintained transmissible viral titres for 2 days longer than controls but did not experience greater WNV-induced mortality during this window. Transcriptionally, ALAN altered the expression of gene regulatory networks including key hubs (OASL, PLBD1 and TRAP1) and effector genes known to affect WNV dissemination (SOCS). Despite mounting anti-viral immune responses earlier, transcriptomic signatures indicated that ALAN-exposed individuals probably experienced pathogen-induced damage and immunopathology, potentially due to evasion of immune effectors. A simple mathematical modelling exercise indicated that ALAN-induced increases of host infectious-to-vector period could increase WNV outbreak potential by approximately 41%. ALAN probably affects other host and vector traits relevant to transmission, and additional research is needed to advise the management of zoonotic diseases in light-polluted areas.
Abstract: 1.Urban areas affect terrestrial ecological processes and local weather, but we know little about their effect on aerial ecological processes. 2.Here, we identify urban from non-urban areas based on the intensity of artificial light at night (ALAN) in the landscape, and, along with weather covariates, evaluate the effect of urbanization on flight altitudes of nocturnally migrating birds. 3.Birds are attracted to ALAN, hence we predicted that altitudes would be lower over urban than over non-urban areas. However, other factors associated with urbanization may also affect flight altitudes. For example, surface temperature and terrain roughness are higher in urban areas, increasing air turbulence, height of the boundary layer, and affecting local winds. 4.We used data from nine weather surveillance radars in the eastern US to estimate altitudes at five quantiles of the vertical distribution of birds migrating at night over urban and non-urban areas during five consecutive spring and autumn migration seasons. We fit generalized linear mixed models by season for each of the five quantiles of bird flight altitude and their differences between urban and non-urban areas. 5.After controlling for other environmental variables and contrary to our prediction, we found that birds generally fly higher over urban areas compared to rural areas in spring, and marginally higher at the mid layers of the vertical distribution in autumn. We also identified a small interaction effect between urbanization and crosswind speed, and between urbanization and surface air temperature, on flight altitudes. We also found that the difference in flight altitudes of nocturnally migrating birds between urban and non-urban areas varied among radars and seasons, but were consistently higher over urban areas throughout the years sampled. 6.Our results suggest that the effects of urbanization on wildlife extend into the aerosphere, and are complex, stressing the need of understanding the influence of anthropogenic factors on airspace habitat. This article is protected by copyright. All rights reserved.
Keywords: Remote Sensing; Animals; Aeroecology; bird migration; flight altitude; light pollution; radar; urbanization
Abstract: Light exerts a major influence on human behaviour and health, mainly owing to the importance of sight in our lives, but also due to its entrainment of daily rhythms via the suprachiasmatic nucleus, the master pacemaker. Light may also be a useful clinical medium, as in lumino-therapy for the improvement of depressed mood. Further, as discussed herein, local application of near infrared light to the substantia nigra exerts neuroprotective properties in models of Parkinson's disease. However, light also has a darker side. In general, as regards the growing problem to human health – and the natural world – of excess exposure to artificial light: both urban glow and ubiquitous screens. Moreover, over-exposure to light, in particular fluorescent light, disrupts circadian rhythms and sleep, and may damage dopaminergic neurons. Is it, then, a neglected risk factor for Parkinson's disease? The present article discusses epidemiological and experimental evidence supporting beneficial and potentially deleterious impact of light on dopaminergic neurons and highlights the mechanisms whereby light might influence neuronal tissue.
Abstract: This paper examines severe light pollution such as commonly found in large urban areas. Light pollution is the unintended negative consequences of poorly designed and injudiciously used artificial lighting. Light pollution generates significant costs including wasted energy and damage to human health, wildlife, recreation, and the beauty of the night sky. Typically, light-pollution models emphasize population density and ignore economic factors. Economic analysis of the issue has been singularly limited. Previous economic research has focused on widespread, but very low levels of light pollution. This paper makes a unique contribution by analyzing economic factors of severe light pollution. The paper utilizes economic data from the World Bank and unique remote sensing data for 184 countries to quantify the economic causes of severe light pollution. Fractional logit models confirm the importance of population and economic factors alike.
Keywords: Economics; light pollution
Abstract: This paper shows the development of a tourism product in a destination that uses the night sky as its main source of attraction. Using this innovative product has helped to create a distinctive image, which is likely to attract a more diverse range of visitors and has assisted in improving economic, social and environmental sustainability. First, we present an overview about sustainable tourism and the sky as a tourism resource followed by a case study, in Portugal, that illustrates the potential of Dark Sky activities for tourism development in rural regions.
Keywords: Society; light pollution; sustainable tourism; rural tourism; Portugal; Alqueva; Dark Sky Reserve