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Author Ma, T.; Zhou, C.; Pei, T.; Haynie, S.; Fan, J.
Title Quantitative estimation of urbanization dynamics using time series of DMSP/OLS nighttime light data: A comparative case study from China's cities Type Journal Article
Year 2012 Publication Remote Sensing of Environment Abbreviated Journal Remote Sensing of Environment
Volume 124 Issue Pages 99-107
Keywords Urbanization; DMSP-OLS; Nighttime light; Statistical analysis; China; remote sensing; satellite; light at night
Abstract Urbanization process involving increased population size, spatially extended land cover and intensified economic activity plays a substantial role in anthropogenic environment changes. Remotely sensed nighttime lights datasets derived from the Defense Meteorological Satellite Program's Operational Linescan System (DMSP/OLS) provide a consistent measure for characterizing trends in urban sprawl over time (Sutton, 2003). The utility of DMSP/OLS imagery for monitoring dynamics in human settlement and economic activity at regional to global scales has been widely verified in previous studies through statistical correlations between nighttime light brightness and demographic and economic variables ( and ). The quantitative relationship between long-term nighttime light signals and urbanization variables, required for extensive application of DMSP/OLS data for estimating and projecting the trajectory of urban development, however, are not well addressed for individual cities at a local scale. We here present analysis results concerning quantitative responses of stable nighttime lights derived from time series of DMSP/OLS imagery to changes in urbanization variables during 1994–2009 for more than 200 prefectural-level cities and municipalities in China. To identify the best-fitting model for nighttime lights-based measurement of urbanization processes with different development patterns, we comparatively use three regression models: linear, power-law and exponential functions to quantify the long-term relationships between nighttime weighted light area and four urbanization variables: population, gross domestic product (GDP), built-up area and electric power consumption. Our results suggest that nighttime light brightness could be an explanatory indicator for estimating urbanization dynamics at the city level. Various quantitative relationships between urban nighttime lights and urbanization variables may indicate diverse responses of DMSP/OLS nighttime light signals to anthropogenic dynamics in urbanization process in terms of demographic and economic variables. At the city level, growth in weighted lit area may take either a linear, concave (exponential) or convex (power law) form responsive to expanding human population and economic activities during urbanization. Therefore, in practice, quantitative models for using DMSP/OLS data to estimate urbanization dynamics should vary with different patterns of urban development, particularly for cities experiencing rapid urban growth at a local scale.
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Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0034-4257 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number IDA @ john @ Serial 219
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Author Perkin, E.K.; Hölker, F.; Tockner, K.; Richardson, J.S.
Title Artificial light as a disturbance to light-naïve streams Type Journal Article
Year 2014 Publication Freshwater Biology Abbreviated Journal Freshw Biol
Volume 59 Issue 11 Pages 2235–2244
Keywords cutthroat trout; drift; invertebrates; light pollution; urbanization; *Fishes; Oncorhynchus clarkii; British Columbia
Abstract Summary

Artificial light at night is prevalent in human-dominated landscapes, and streams in these landscapes can be expected to be affected by artificial lights. We hypothesised that artificial light at night would reduce the activity of aquatic insects, resulting in reduced drift rates, lower fish growth rates and lower leaf litter decomposition rates.

We tested these hypotheses by installing street lights to reaches in four forested, natural streams of coastal British Columbia each paired with a control reach. Cutthroat trout (Oncorhynchus clarkii) are the top predators in these streams and feed mostly on terrestrial and drifting aquatic invertebrates.

We found that the night-time drift of aquatic invertebrates in lit reaches was ˜50% of the drift in dark reaches. However, the density of emerging aquatic insects, the density of insects falling into reaches, leaf litter decomposition rate and the number and growth rate of trout caught were not significantly different between the dark and experimentally lit reaches.

We conclude that, while short-term exposure to artificial light during the summer changes invertebrate behaviour, it does not significantly alter other trophic levels in forested headwater streams. Our results suggest that low levels of artificial light do not strongly influence stream ecosystems, but future research should determine whether this is true for all seasons and longer-term exposure to light.
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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 0046-5070 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number IDA @ john @ Serial 361
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