Would you like to know more? The effect of personalized wildfire risk information and social comparisons on information-seeking behavior in the wildland–urban interface     

Meldrum  James R.  Brenkert-Smith  Hannah  Champ  Patricia A.  Gomez  Jamie  Byerly  Hilary  Falk  Lilia  Barth  Christopher M. 《Natural Hazards》2021,106(3):2139-2161

Natural Hazards - Private landowners are important actors in landscape-level wildfire risk management. Accordingly, wildfire programs and policy encourage wildland–urban interface homeowners...  相似文献   

A machine learning approach for regional geochemical data:Platinum-group element geochemistry vs geodynamic settings of the North Atlantic Igneous Province     

Jordan J. Lindsay  Hannah S.R. Hughes  Christopher M. Yeomans  Jens C.Ø. Andersen  Iain McDonald 《地学前缘(英文版)》2021,12(3):101098

Whilst traditional approaches to geochemistry provide valuable insights into magmatic processes such as melting and element fractionation, by considering entire regional data sets on an objective basis using machine learning algorithms(MLAs), we can highlight new facets within the broader data structure and significantly enhance previous geochemical interpretations.The platinum-group element(PGE) budget of lavas in the North Atlantic Igneous Province(NAIP) has been shown to vary systematically according to age, geographic location and geodynamic environment.Given the large multi-element geochemical data set available for the region, MLAs were employed to explore the magmatic controls on these shifting concentrations.The key advantage of using machine learning in analysis is its ability to cluster samples across multi-dimensional(i.e., multi-element)space.The NAIP data set is manipulated using Principal Component Analysis(PCA) and t-Distributed Stochastic Neighbour Embedding(t-SNE) techniques to increase separability in the data alongside clustering using the k-means MLA.The new multi-element classification is compared to the original geographic classification to assess the performance of both approaches.The workflow provides a means for creating an objective high-dimensional investigation on a geochemical data set and particularly enhances the identification of metallogenic anomalies across the region.The techniques used highlight three distinct multi-element end-members which successfully capture the variability of the majority of elements included as input variables.These end-members are seen to fluctuate in prominence throughout the NAIP, which we propose reflects the changing geodynamic environment and melting source.Crucially, the variability of Pt and Pd are not reflected in MLA-based clustering trends, suggesting that they vary independently through controls not readily demonstrated by the NAIP major or trace element data structure(i.e., other proxies for magmatic differentiation).This data science approach thus highlights that PGE(here signalled by Pt/Pd ratio) may be used to identify otherwise localised or cryptic geochemical inputs from the subcontinental lithospheric mantle(SCLM) during the ascent of plume-derived magma, and thereby impact upon the resulting metallogenic basket.  相似文献   

Acoustic monitoring of gas emissions from the seafloor. Part II: a case study from the Sea of Marmara     

Gaye Bayrakci  Carla Scalabrin  Stéphanie Dupré  Isabelle Leblond  Jean-Baptiste Tary  Nadine Lanteri  Jean-Marie Augustin  Laurent Berger  Estelle Cros  André Ogor  Christos Tsabaris  Marc Lescanne  Louis Géli 《Marine Geophysical Researches》2014,35(3):211-229

A rotating, acoustic gas bubble detector, BOB (Bubble OBservatory) module was deployed during two surveys, conducted in 2009 and 2011 respectively, to study the temporal variations of gas emissions from the Marmara seafloor, along the North Anatolian Fault zone. The echosounder mounted on the instrument insonifies an angular sector of 7° during a given duration (of about 1 h). Then it rotates to the next, near-by angular sector and so forth. When the full angular domain is insonified, the “pan and tilt system” rotates back to its initial position, in order to start a new cycle (of about 1 day). The acoustic data reveal that gas emission is not a steady process, with observed temporal variations ranging between a few minutes and 24 h (from one cycle to the other). Echo-integration and inversion performed on the acoustic data as described in the companion paper of Leblond et al. (Mar Geophys Res, 2014), also indicate important variations in, respectively, the target strength and the volumetric flow rates of individual sources. However, the observed temporal variations may not be related to the properties of the gas source only, but reflect possible variations in sea-bottom currents, which could deviate the bubble train towards the neighboring sector. During the 2011 survey, a 4-component ocean bottom seismometer (OBS) was co-located at the seafloor, 59 m away from the BOB module. The acoustic data from our rotating, monitoring system support, but do not provide undisputable evidence to confirm, the hypothesis formulated by Tary et al. (2012), that the short-duration, non-seismic micro-events recorded by the OBS are likely produced by gas-related processes within the near seabed sediments. Hence, the use of a multibeam echosounder, or of several split beam echosounders should be preferred to rotating systems, for future experiments.  相似文献   

Environmental impact and geochemical behavior of soil contaminants from an industrial waste landfill in Southern Brazil     

P. V. Augustin Jr.  A. P. Viero 《Environmental Earth Sciences》2012,67(5):1521-1530

Industrial waste landfills produce great impacts on soil and groundwater. There are many industrial waste landfills in Vale dos Sinos, Southern Brazil, which were inadequately planned and maintained since the industry started in the first half of the twentieth century. The largest industrial landfill in the Valley, which causes the most severe impacts on soil and groundwater, is the subject of this paper, which studies the environmental impacts and behavior of contaminants in soil. The landfill was carefully mapped on a scale of 1:1,000; 88 samples were collected from soil probes; the leachate of three samples was comprehensively analyzed; and soils mineralogy and chemistry were studied. Few studies have been made on this landfill. This study shows widespread contamination of soil in the surrounding areas of the landfill. Chromium, chloride and ammonium have the highest contamination levels, reflecting their high contents in landfill leachate. Contamination by petroleum hydrocarbons, cyanide and mercury is registered in more than 65% of soil samples with low concentrations. Lead, copper and barium show low contamination restricted to a few soil samples. Soil contamination occurs mainly in the unsaturated zone of the aquifer at the convergence points of stormwater, showing that the preferential transport of contaminants occurs on surface flow followed by soil infiltration. The results of leaching tests indicate high metal sorption capacity of soil. The remediation of contaminated soil must contain at least the following actions: sealing the top of the landfill, installation of geochemical barriers, removal of the liquid waste basins without sealing the base and collection and treatment of the rainwater drainage.  相似文献   

Distinguishing human from animal faecal contamination in water: A review     

L. W. Sinton  R. K. Finlay  D. J. Hannah 《新西兰海洋与淡水研究杂志》2013,47(2):323-348

Management of faecal contamination of water would be improved if sources could be accurately identified through water analysis. Human faeces are generally perceived as constituting a greater human health risk than animal faeces, but reliable epidemiological evidence is lacking. United States waterborne disease data suggest that human‐specific enteric viruses account for over half the documented outbreaks. However, in New Zealand, where there is a high grazing animal:human ratio (increasing the relative importance of water‐transmissible zoonoses), it seems prudent to assume that human and animal faecal pollution both constitute a risk to human health. Irrespective of the relative risks, the ability to identify sources would assist in overall management of microbial water quality. Faecal streptococci do not appear to provide reliable faecal source identification. Human and animal sources, respectively, maybe distinguishable by two tests on Bifidobacterium spp.—growth at 45°C in trypticase phytone yeast broth and sorbitol fermentation. Different species of Bacteroides tend to be present in humans and animals, but poor survival in water is a problem. Phages of the Bacteroides fragilis strain HSP40 appear to be human specific, but low counts in effluent in some countries, including New Zealand, may limit their usefulness. Different F‐RNA phage subgroups appear to be associated with human and animal faecal sources. The actinomycete Rhodococcus coprophilus has potential as a grazing animal indicator but it is persistent, and existing culturing techniques are time consuming. The development of DNA‐based techniques, such as polymerase chain reaction (PCR), may assist in the assay of some microbial faecal source indicators. Various faecal sterol isomers offer the possibility of distinguishing between human and animal sources, and even between different animals. Washing powder constituents such as fluorescent whitening agents, sodium tripolyphosphate and linear alkyl benzenes, offer useful human source identifiers. It is unlikely that any single determinand will be useful in all situations, but statistical analysis of appropriate “baskets” of microbial and chemical determinands offers the possibility of identifying and apportioning human and animal faecal inputs to natural waters.  相似文献