|
|
Xiaolong, G., Mo, Z., Xian, L., Ce, S., Changbin, S., & Ying, L. (2016). Effects of LED light quality on the growth, metabolism, and energy budgets of Haliotis discus discus. Aquaculture, 453, 31–39.
Abstract: In this study, a bioenergetics approach was used to examine the effects of different LED light qualities (red, orange, blue, green light, natural light and a dark setting) on the growth and survival of the abalone Haliotis discus discus, and its physiological response mechanism under different light qualities. The results suggest that under blue or green light, the survival rate, specific growth rate, food intake, and food conversion efficiency of H. d. discus were significantly lower than in those groups under red or orange light (P < 0.05). Under red or orange light, pepsin, amylase and cellulose activity was significantly higher than those in any other light quality group (P < 0.05), whereas lipase activity exhibited no significant difference among the light quality groups (P > 0.05). Under blue or green light, lactate dehydrogenase activity and lactic acid content were higher (P < 0.05), suggesting enhanced anaerobic metabolism. Under blue or green light, H. d. discus lost more energy via excretion, feces and respiration than was acquired from its food. Under red or orange light, H. d. discus acquired more energy from its food and lost less energy via excretion and feces; as a result, its assimilation efficiency (K1) and net growth efficiency (K2) were significantly higher than those of any other group (P < 0.05). Therefore, we suggest that red or orange light should be used as a light source for the aquaculture of H. d. discus.
|
|
|
|
Jean, N., Burke, M., Xie, M., Davis, W. M., Lobell, D. B., & Ermon, S. (2016). Combining satellite imagery and machine learning to predict poverty. Science, 353(6301), 790–794.
Abstract: Nighttime lighting is a rough proxy for economic wealth, and nighttime maps of the world show that many developing countries are sparsely illuminated. Jean et al. combined nighttime maps with high-resolution daytime satellite images (see the Perspective by Blumenstock). With a bit of machine-learning wizardry, the combined images can be converted into accurate estimates of household consumption and assets, both of which are hard to measure in poorer countries. Furthermore, the night- and day-time data are publicly available and nonproprietary.
|
|
|
|
Kintisch, E. (2016). Voyage into darkness (Vol. 351).
|
|
|
|
Traill, L. W., Martin, J., & Owen-Smith, N. (2016). Lion proximity, not moon phase, affects the nocturnal movement behaviour of zebra and wildebeest. J Zool, 299(3), 221–227.
Abstract: Moon phase affects nocturnal activity patterns in mammals. Among ungulates, a number of studies have found animals to be more active over full moon nights. This may be because increased luminosity provides increased opportunity to forage and/or increased ability to detect predators; known as the visual acuity hypothesis. Here, we use GPS-derived movement data to test for the influence of moon phase on plains zebra Equus quagga and blue wildebeest Connochaetes taurinus activity in Kruger National Park, South Africa. We compare animal movement (rate and displacement) over full and new moon nights, and consider the effect of lion proximity. We found that lion proximity largely determined the nocturnal movements of zebra and wildebeest, not moon phase. When lions were >1 km away, there was no difference in the nocturnal movement activity of prey animals over full and new moon conditions, contradicting previous findings. When lions were within 1 km of these animals, however, the movement of zebra and wildebeest greatly increased over the new moon, the relatively dark period when lion were most likely hunting. Although we could not explicitly test for predator detection here, our findings suggest that the visual acuity hypothesis does not hold for zebra and wildebeest in Kruger National Park (KNP) given that there is no evidence for increased foraging activity over the full moon. The influence of moon phase on the nocturnal activity of African ungulates may be more complicated than anticipated, and we suggest that this cannot be estimated unless predator proximity is accounted for.
|
|
|
|
ffrench-Constant, R., Somers-Yeates, R., Bennie, J., Economou, T., Hodgson, D., Spalding, A., et al. (2016). Light pollution is associated with earlier tree budburst across the United Kingdom. Proc Roy Soc B Biol Sci, 283(1833), 1–9.
Abstract: The ecological impact of night-time lighting is of concern because of its well-demonstrated effects on animal behaviour. However, the potential of light pollution to change plant phenology and its corresponding knock-on effects on associated herbivores are less clear. Here, we test if artificial lighting can advance the timing of budburst in trees. We took a UK-wide 13 year dataset of spatially referenced budburst data from four deciduous tree species and matched it with both satellite imagery of night-time lighting and average spring temperature. We find that budburst occurs up to 7.5 days earlier in brighter areas, with the relationship being more pronounced for later-budding species. Excluding large urban areas from the analysis showed an even more pronounced advance of budburst, confirming that the urban ‘heat-island’ effect is not the sole cause of earlier urban budburst. Similarly, the advance in budburst across all sites is too large to be explained by increases in temperature alone. This dramatic advance of budburst illustrates the need for further experimental investigation into the impact of artificial night-time lighting on plant phenology and subsequent species interactions. As light pollution is a growing global phenomenon, the findings of this study are likely to be applicable to a wide range of species interactions across the world.
|
|
