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Gómez, C., & Mitchell, C. A. (2016). Physiological and Productivity Responses of High-wire Tomato as Affected by Supplemental Light Source and Distribution within the Canopy. J. Amer. Soc. Hort. Sci., 141(2), 196–208.
Abstract: The relative coolness-to-touch of light-emitting diodes (LEDs) has enabled commercial implementation of intracanopy lighting (ICL) in the greenhouse. Intracanopy lighting, which refers to the strategy of lighting along the side or from within the foliar canopy, can increase canopy photosynthetic activity, but physiological and productivity responses of high-wire greenhouse tomato (Solanum lycopersicum) to intracanopy supplemental lighting (SL) still are not yet fully understood. Two consecutive production experiments were conducted across seasons in a glass-glazed greenhouse located in a midnorthern, continental climate [lat. 40°N (West Lafayette, IN)]. Plants were grown from winter-to-summer [increasing solar daily light integral (DLI)] and from summer-to-winter (decreasing solar DLI) to compare three SL strategies for high-wire tomato production across changing solar DLIs: top lighting with high-pressure sodium lamps (HPS) vs. intracanopy LED vertical towers vs. hybrid SL (HPS + horizontal ICL-LEDs). A control treatment also was included for which no SL was provided. Supplemental DLI for each experimental period was adjusted monthly, to complement seasonal changes in sunlight, aiming to approach a target total DLI of 25 mol·m‒2·d‒1 during fruit set. Harvest parameters (total fruit fresh weight, number of fruit harvested, and average cluster fresh weight), tissue temperature, chlorophyll fluorescence, and stomatal conductance (gS) were unaffected by SL treatment in both experiments. Among the physiological parameters evaluated, CO2 assimilation measured under light-saturating conditions, light-limited quantum-use efficiency, and maximum gross CO2 assimilation (Amax) proved to be good indicators of how ICL reduces the top-to-bottom decline in leaf photosynthetic activity otherwise measured with top lighting only (HPS-SL or solar). Although SL generally increased fruit yield relative to control, lack of SL treatment differences among harvest parameters indicates that higher crop photosynthetic activity did not increase fruit yield. Compared with control, intracanopy SL increased yield to the same extent as top SL, but the remaining photoassimilate from ICL most likely was partitioned to maintain nonharvested, vegetative plant parts as well.
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Grove, L. (2016). Reducing Acadia's Light Pollution. Master's thesis, University of Virginia, Charlottesville.
Abstract: Acadia National Park is among the most visited national parks in the United States, attracting millions of people per year. Thousands of those visitors come to the park for “astro-tourism,” as Acadia has become one of the premier stargazing locations on the east coast. There remains, however, the continued threat from light pollution from the surrounding communities that negatively affects Acadia's darkness, contributing to a lesser visitor experience and potentially harming native ecosystems. Although park management and community organizations have engaged in significant efforts to decrease Acadia's nighttime light levels and raise awareness among visitors and locals regarding the importance of darkness, the park still seek to continue to decrease light pollution. This report developed policy options that could help solve the long-term policy goal of decreasing nighttime lighting levels within and around Acadia while also using the International Dark-Sky Association's Dark-Sky Park designation requirements as a reasonable, short-term policy benchmark.
Working within existing organizations, the policy options crafted to address Acadia’s nighttime lighting levels were analyzed both qualitatively through a criteria evaluation and quantitatively through a Benefit Cost Analysis.
The options included 1) the formation of a Darkness Coalition within the League of Towns, 2) a reimagining of the Worcester Polytechnic Institute Dark-Sky Project into the Dark-Sky Taskforce, 3) the creation of a Lighting Consultant position paid through the Friends of Acadia Wild Acadia initiative, and 4) the combination of Coalition and the Taskforce into the League of Towns – Dark-Sky Partnership (LOT-DSP). The report recommends the adoption of Option 4 – the creation of the LOT – DSP. While this option does not provide the greatest estimated monetary net value compared to the Status Quo in the quantitative evaluation, it still provides an estimated benefit of about $105 million over the course of five years and is the strongest option in the qualitative analysis. The LOT – DSP provides the best opportunity for Acadia to achieve legitimate and long-lasting nighttime light level reduction.
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Grunsven van, R. H. A., Creemers, R., Joosten, K., Donners Maurice, & Veenendaal, E. M. (2016). Behaviour of migrating toads under artificial lights differs from other phases of their life cycle. AMRE, .
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Gutierrez-Escolar, A., Castillo-Martinez, A., Gomez-Pulido, J., Gutierrez-Martinez, J. - M., González-Seco, E., & Stapic, Z. (2016). A review of energy efficiency label of street lighting systems. Energy Efficiency, , 1–18.
Abstract: There are very few countries that have provisions addressing the energy efficiency of the whole street lighting system, such as Spain or the Netherlands. Nevertheless, there is not an agreement about how energy efficiency must be assessed. The Spanish Government contemplates it in the Royal Decree 1890/2008 with the goal of improving energy savings and efficiency. However, this has not obtained the expected results. Nowadays, energy efficiency of this kind of systems is assessed using a label. In the case of Spain, this label only assesses one magnitude. The contributions of this paper are two evaluation systems (kiviat diagram and pie chart) which assess five magnitudes: lamps, energy efficiency index, light pollution, renewable energy contribution, and harness of the luminous flux using dimming. After that, a survey was done to study several subjects: (1) if citizens are aware about the efficiency of street lighting systems, (2) whether the sample of colors used in the label is adequate, and (3) if our proposed systems could replace the current evaluation system. Finally, the paper finishes with the conclusions of the survey.
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Hall, A. S. (2016). Acute Artificial Light Diminishes Central Texas Anuran Calling Behavior. Amer. Midland Naturalist, 175(2), 183–193.
Abstract: Male anuran (frog and toad) advertisement calls associate with fitness and can respond to environmental cues such as rain and air temperature. Moonlight is thought to generally decrease call behaviors â perhaps as a response to increased perceived risk of predation â and this study sought to determine if artificial lighting produces a similar pattern. Using a handheld spotlight, light was experimentally introduced to natural anuran communities in ponds and streams. Custom call surveys where then used to measure anuran calls in paired unlit and lit conditions at six locations in central Texas. Among seven species heard, the number of frogs calling and call index declined in response to the acute light input. Local weather conditions could not explain differences between numbers of frogs calling between species, sites, survey order, or lighting order suggesting the main effect on number calling was light treatment. It appears acute artificial light alone can change calling behavior within several species in natural, mixed species assemblages.
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