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Author Taylor, G.; Davies, W.J. url  doi
openurl 
  Title The Control Of Leaf Growth Of Betula And Acer By Photoenvironment Type Journal Article
  Year 1985 Publication New Phytologist Abbreviated Journal New Phytol  
  Volume 101 Issue 2 Pages 259-268  
  Keywords Plants  
  Abstract Leaf extension of one‐year‐old seedlings of silver birch (Betula pendula Roth.) and sycamore (Acer pseudoplatanus L.), was measured using linear variable transducers (LVDTs) interfaced to a microcomputer. Birch and sycamore seedlings exhibited contrasting patterns of leaf extension during a diurnal cycle with a 16 h photoperiod. Birch leaves grew more rapidly when illuminated; growth during the photoperiod was approximately doubled when compared with growth in the dark. Mean relative growth rates ±SE at ‘lights‐on + 3 h’ and ‘lights‐off + 5 h’ were 0.0136 ± 0.0016 and 0.0066 ± 0.0005 h−1 respectively. In direct contrast, growth of sycamore leaves was increased when leaves were darkened; mean relative growth rates + SE at ‘lights‐on+3 h’ and ‘lights‐off + 5 h’ were 0.0056 ± 0.0005 and 0.0094 ± 0.0008 h‐1 respectively.

When leaves of birch and sycamore were darkened, increased leaf turgor was measured in both species, but only in sycamore was this higher night‐time turgor associated with a higher rate of leaf growth.

Cell wall extensibility (WEX), an indication of the ability of cell walls to loosen and extend irreversibly, and cell surface pH were assessed in darkened and illuminated leaves of both species. An increase in WEX was measured when birch leaves were illuminated (P≤ 0.001) and this was accompanied by a decline in cell surface pH (P≤ 0.001). However, when leaves of sycamore were illuminated, WEX declined (P≤ 005) and cell surface pH increased (P≤ 0.001).

The ability of these species to survive beneath a woodland canopy is discussed in relation to the cellular factors controlling their leaf growth.
 
  Address (up)  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0028-646X ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number GFZ @ kyba @ Serial 1992  
Permanent link to this record
 

 
Author Wren, W.; Locke, S. url  doi
openurl 
  Title Upgraded Rig Lighting Improves Night Time Visibility While Reducing Stray Light and the Threat to Dark Skies in West Texas Type Conference Article
  Year 2015 Publication Society of Petroleum Engineers Abbreviated Journal Soc. Petrol. Engr.  
  Volume Issue Pages  
  Keywords Lighting; outdoor lighting; petroleum; oil and gas; lighting engineering  
  Abstract McDonald Observatory, part of the University of Texas at Austin, is a world-class astronomical-research facility representing hundreds of millions of dollars of public and private investment that is increasingly threatened by nighttime lighting from oil-and-gas-related activities in and around the Permian Basin. Established in the remote Davis Mountains of West Texas in 1932, the observatory is home to some of the world's largest telescopes and it has continued as a world-renowned research center. Dark night skies are crucial to its mission. Since 2010, however, the sky along the observatory's northern horizon, in the direction of the Permian Basin, has been steadily and rapidly brightening, due to new exploration for oil and gas. The pace has been accelerating: More than 2,000 applications were filed over the past year to drill in the region. In 2011, the State of Texas enacted a law that instructs the seven counties surrounding McDonald Observatory, an area covering some 28,000 square miles, to adopt outdoor lighting ordinances designed to preserve the dark night skies for ongoing astronomical research at the observatory. Most had already done so voluntarily, but additional effort is needed throughout the area to address fast-moving energy-exploration activities.

A joint project between McDonald Observatory and Pioneer Energy Services (PES) has demonstrated that many of the adverse effects of oilfield lighting can be mitigated, without jeopardizing safety, through proper shielding and aiming of light fixtures. Beginning July, 2013, PES granted the observatory access to a working rig, Pioneer Rig #29. Every time the rig moved to a new location, there was an opportunity to install shields, re-aim floodlights, and evaluate effectiveness.

This joint project demonstrated that, in many cases, nighttime visibility on the rig can be significantly improved. Many light fixtures, which had been sources of blinding glare due to of lack of shielding, poor placement, or poor aiming, were made better and safer, using optional glare shields that are offered by manufacturers for a variety of fixture models. Proper shielding and aiming of existing fixtures improves visibility and reduces wasted uplight. New lighting systems that take advantage of light-emitting-diode technology also promise better directionality, reduced fuel consumption, and darker skies overhead.

The oil-and-gas industry has been lighting its exploration and production activities in much same way for more than 100 years, with little to no consideration of environmental impacts. The opportunity exists to adopt new lighting practices and technologies that improve safety, reduce costs, and help preserve our vanishing night skies so that important ongoing scientific exploration can continue.
 
  Address (up)  
  Corporate Author Thesis  
  Publisher Society of Petroleum Engineers Place of Publication Editor  
  Language English Summary Language English Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Medium  
  Area Expedition Conference  
  Notes SPE E&P Health, Safety, Security and Environmental Conference-Americas held in Denver, Colorado, USA, 16–18 March 2015 Approved no  
  Call Number IDA @ john @ Serial 1993  
Permanent link to this record
 

 
Author Zhao, N.; Cao, G.; Zhang, W.; Samson, E.L. url  doi
openurl 
  Title Tweets or nighttime lights: Comparison for preeminence in estimating socioeconomic factors Type Journal Article
  Year 2018 Publication ISPRS Journal of Photogrammetry and Remote Sensing Abbreviated Journal ISPRS Journal of Photogrammetry and Remote Sensing  
  Volume 146 Issue Pages 1-10  
  Keywords Remote Sensing  
  Abstract Nighttime lights (NTL) imagery is one of the most commonly used tools to quantitatively study socioeconomic systems over large areas. In this study we aim to use location-based social media big data to challenge the primacy of NTL imagery on estimating socioeconomic factors. Geo-tagged tweets posted in the contiguous United States in 2013 were retrieved to produce a tweet image with the same spatial resolution of the NTL imagery (i.e., 0.00833° × 0.00833°). Sum tweet (the total number of tweets) and sum light (summed DN value of the NTL image) of each state or county were obtained from the tweets and the NTL images, respectively, to estimate three important socioeconomic factors: personal income, electric power consumption, and fossil fuel carbon dioxide emissions. Results show that sum tweet is a better measure of personal income and electric power consumption while carbon dioxide emissions can be more accurately estimated by sum light. We further exploited that African-Americans adults are more likely than White seniors to post geotagged tweets in the US, yet did not find any significant correlations between proportions of the subpopulations and the estimation accuracy of the socioeconomic factors. Existence of saturated pixels and blooming effects and failure to remove gas flaring reduce quality of NTL imagery in estimating socioeconomic factors, however, such problems are nonexistent in the tweet images. This study reveals that the number of geo-tagged tweets has great potential to be deemed as a substitute of brightness of NTL to assess socioeconomic factors over large geographic areas.  
  Address (up)  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0924-2716 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number GFZ @ kyba @ Serial 1994  
Permanent link to this record
 

 
Author Ma, T. url  doi
openurl 
  Title Multi-Level Relationships between Satellite-Derived Nighttime Lighting Signals and Social Media–Derived Human Population Dynamics Type Journal Article
  Year 2018 Publication Remote Sensing Abbreviated Journal Remote Sensing  
  Volume 10 Issue 7 Pages 1128  
  Keywords Remote Sensing  
  Abstract Satellite-based measurements of the artificial nighttime light brightness (NTL) have been extensively used for studying urbanization and socioeconomic dynamics in a temporally consistent and spatially explicit manner. The increasing availability of geo-located big data detailing human population dynamics provides a good opportunity to explore the association between anthropogenic nocturnal luminosity and corresponding human activities, especially at fine time/space scales. In this study, we used Visible Infrared Imaging Radiometer Suite (VIIRS) day/night band (DNB)–derived nighttime light images and the gridded number of location requests (NLR) from China’s largest social media platform to investigate the quantitative relationship between nighttime light radiances and human population dynamics across China at four levels: the provincial, city, county, and pixel levels. Our results show that the linear relationship between the NTL and NLR might vary with the observation level and magnitude. The dispersion between the two variables likely increases with the observation scale, especially at the pixel level. The effect of spatial autocorrelation and other socioeconomic factors on the relationship should be taken into account for nighttime light-based measurements of human activities. Furthermore, the bivariate relationship between the NTL and NLR was employed to generate a partition of human settlements based on the combined features of nighttime lights and human population dynamics. Cross-regional comparisons of the partitioned results indicate a diverse co-distribution of the NTL and NLR across various types of human settlements, which could be related to the city size/form and urbanization level. Our findings may provide new insights into the multi-level responses of nighttime light signals to human activity and the potential application of nighttime light data in association with geo-located big data for investigating the spatial patterns of human settlement.  
  Address (up)  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2072-4292 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number GFZ @ kyba @ Serial 1996  
Permanent link to this record
 

 
Author Jiang, W.; He, G.; Long, T.; Guo, H.; Yin, R.; Leng, W.; Liu, H.; Wang, G. url  doi
openurl 
  Title Potentiality of Using Luojia 1-01 Nighttime Light Imagery to Investigate Artificial Light Pollution Type Journal Article
  Year 2018 Publication Sensors Abbreviated Journal Sensors  
  Volume 18 Issue 9 Pages 2900  
  Keywords Remote Sensing; Instrumentation  
  Abstract The successful launch of Luojia 1-01 complements the existing nighttime light data with a high spatial resolution of 130 m. This paper is the first study to assess the potential of using Luojia 1-01 nighttime light imagery for investigating artificial light pollution. Eight Luojia 1-01 images were selected to conduct geometric correction. Then, the ability of Luojia 1-01 to detect artificial light pollution was assessed from three aspects, including the comparison between Luojia 1-01 and the Suomi National Polar-Orbiting Partnership Visible Infrared Imaging Radiometer Suite (NPP-VIIRS), the source of artificial light pollution and the patterns of urban light pollution. Moreover, the advantages and limitations of Luojia 1-01 were discussed. The results showed the following: (1) Luojia 1-01 can detect a higher dynamic range and capture the finer spatial details of artificial nighttime light. (2) The averages of the artificial light brightness were different between various land use types. The brightness of the artificial light pollution of airports, streets, and commercial services is high, while dark areas include farmland and rivers. (3) The light pollution patterns of four cities decreased away from the urban core and the total light pollution is highly related to the economic development. Our findings confirm that Luojia 1-01 can be effectively used to investigate artificial light pollution. Some limitations of Luojia 1-01, including its spectral range, radiometric calibration and the effects of clouds and moonlight, should be researched in future studies.  
  Address (up)  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1424-8220 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number GFZ @ kyba @ Serial 1997  
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