Abstract: A short exposure to light during relative night (night break; NB) delays flowering in the short day plant rice. NB acts by downregulating Heading date 3a (Hd3a) expression. Because phytochrome B mutants do not respond to NB and their flowering time is not affected even under NB conditions, phyB is required for the suppression of Hd3a expression. The effect of NB is quantitatively controlled by light quality and by either light intensity or duration. However, the molecular mechanisms that regulate these interactions are poorly understood. Here, we examine the roles of phytochromes in the regulation of Hd3a transcription under NB conditions using monochromatic red, far-red and blue light. Red and blue light downregulated Hd3a expression, but far-red light NB did not. The effect of red light NB on Hd3a is dependent on photon fluence and is restored by subsequent far-red light irradiation. Our results suggest that quantitative effect of light on flowering in rice NB is mediated by the regulation of Hd3a transcription by phyB.
Keywords: Plants; Flowers/*genetics/growth & development; Gene Expression Regulation, Developmental/drug effects; Gene Expression Regulation, Plant/drug effects; Light; Mutation; Oryza/*genetics/growth & development; Photoperiod; Phytochrome B/genetics/*physiology; Plant Proteins/*genetics; Transcription, Genetic
Abstract: The persistent increase of artificial light emissions is causing a progressive brightening of the night sky in most regions of the world. This process is a threat for the long-term sustainability of the scientific and educational activity of ground-based astronomical observatories operating in the optical range. Huge investments in building, scientific and technical workforce, equipment and maintenance can be at risk if the increasing light pollution levels hinder the capability of carrying out the top-level scientific observations for which these key scientific infrastructures were built. Light pollution has other negative consequences, as e.g. biodiversity endangering and the loss of the starry sky for recreational, touristic and preservation of cultural heritage. The traditional light pollution mitigation approach is based on imposing conditions on the photometry of individual sources, but the aggregated effects of all sources in the territory surrounding the observatories are seldom addressed in the regulations. We propose that this approach shall be complemented with a top-down, ambient artificial skyglow immission limits strategy, whereby clear limits are established to the admissible deterioration of the night sky above the observatories. We describe the general form of the indicators that can be employed to this end, and develop linear models relating their values to the artificial emissions across the territory. This approach can be easily applied to other protection needs, like e.g. to protect nocturnal ecosystems, and it is expected to be useful for making informed decisions on public lighting, in the context of wider spatial planning projects.
Keywords: Skyglow; Regulation; Lighting
Abstract: Artificial lighting has received increased attention from urban scholars and geographers in recent years. It is celebrated for its experimental aesthetics and experiential qualities and critiqued for its adverse effects on biological life and the environment. Yet scholars and practitioners unite in their disapproval of uniform and homogenous lighting that follows from standardised lighting technologies and design principles. Absent from debates in urban scholarship and geography, however, is any serious consideration of how lighting designers respond to such standardised measures and regulations. In this article, I address this lack of academic attention by exploring how designers overturn the restrictive challenges posed by the standards and regulations of the design and planning process. Drawing on interviews with designers involved in the lighting design of a mixed-use redevelopment project in Canning Town, East London, I demonstrate how the interpretation and translation of lighting standards and regulations resist the tendency to predetermine design aesthetics and functions. By drawing attention away from the technical specifications and numerical values that are prescribed in standards and regulations, and towards lighting’s experiential and performative effects, the article argues that lighting designers can play an important role in challenging how standards and regulations are measured, defined and maintained. Calling on urban scholars to play a more prominent role in foregrounding this process of translation, I suggest that standards and regulations can provide frameworks within which luminous differentiation and preservation of darkness can be achieved, playing a potentially crucial role in ensuring a socially and environmentally sustainable transition to energy efficient lighting.
Keywords: Regulation; Lighting; Conservation; Darkness; Planning; Society
Abstract: A substantial body of research on natural quiet and natural darkness in national
parks, and protected areas more broadly, has been reported in the scientific and professional literature in recent years. However, this literature is widely scattered over many academic and professional journals that cover both the natural and social sciences. To help integrate and synthesize this body of work, we surveyed this diverse literature and collected representative examples in a book (Manning et al. 2018). We conclude our book with a series of principles
that we have distilled to help guide park managers to protect natural quiet and natural darkness. This paper presents those principles.
Much of our book focuses on national parks in the United States, and in the remainder of this paper the phrase “the national parks” refers to them. But we feel that the principles we have derived from our review of the scientific and professional literature on natural quiet and natural darkness apply equally well to a variety of parks and protected areas in the United States and elsewhere.
Natural quiet is generally defined as the sounds of nature uninterrupted by human-caused noise, and natural darkness is darkness unaffected by human-caused light. It is important to note that natural quiet and natural darkness do not necessarily mean absolute quiet or darkness, as the natural world often generates sounds of its own (e.g., birds calling, wind blowing,
rivers rushing) and has sources of illumination (e.g., the glow of celestial bodies and the fluorescence of some plants and animals).
parks, and protected areas more broadly, has been reported in the scientific and professional literature in recent years. However, this literature is widely scattered over many academic and professional journals that cover both the natural and social sciences. To help integrate and synthesize this body of work, we surveyed this diverse literature and collected representative examples in a book (Manning et al. 2018). We conclude our book with a series of principles
that we have distilled to help guide park managers to protect natural quiet and natural darkness. This paper presents those principles.
Much of our book focuses on national parks in the United States, and in the remainder of this paper the phrase “the national parks” refers to them. But we feel that the principles we have derived from our review of the scientific and professional literature on natural quiet and natural darkness apply equally well to a variety of parks and protected areas in the United States and elsewhere.
Natural quiet is generally defined as the sounds of nature uninterrupted by human-caused noise, and natural darkness is darkness unaffected by human-caused light. It is important to note that natural quiet and natural darkness do not necessarily mean absolute quiet or darkness, as the natural world often generates sounds of its own (e.g., birds calling, wind blowing,
rivers rushing) and has sources of illumination (e.g., the glow of celestial bodies and the fluorescence of some plants and animals).
Keywords: Conservation; Planning; Regulation
Abstract: This comment explores the negative effects of light pollution and considers whether current levels of artificial light at night (LAN) warrant federal control by the Environmental Protection Agency (EPA). This study first identifies the negative effects of light pollution on human health and the environment, treatment of which aligns with the mission statement of the EPA. Light pollution comprises both a private and a public nuisance. Next, this comment assesses the effectiveness of the common law approach, local government, state government, and federal control over light pollution in this context to determine which form of governance is most effective. Then, EPA involvement through federal and state implemented plans, as well as federal regulation of manufacturing is investigated. Last, this comment considers the necessity of private action through an emerging legal reform called new governance, which emphasizes public-private approaches. The negative effects of light pollution on human health and the environment could eventually lead the EPA to assert control over the regulation of light pollution, but under the current presidential administration this is highly unlikely. The predicted lack of government action leads me to call for nongovernment organizations (NGOs) to step in and take action to privately regulate light pollution and mitigate its negative effects through certification regimes, insurance premium incentives, and corporate social responsibility until government exerts regulatory control.
Keywords: Society; law; light pollution; regulation; environmentalism