Miracle-dz/UniFAR-FTUs huggingface dataset:
Mapping health levels of Robinia pseudoacacia forests in the Yellow River delta, China, using IKONOS and Landsat 8 OLI imagery

The largest artificial Robinia pseudoacacia forests in the Yellow River delta of China have been infected by dieback diseases. Over the past several decades, this has caused a large amount of mortality of Robinia pseudoacacia forests in this area. Timely and accurate information on the health levels of the forests is crucial to improving local ecological and economic conditions. Remote sensing has been demonstrated to be a useful tool to map forest diseases over a large area. In this study, IKONOS and Landsat 8 Operational Land Imager (OLI) sensor data were collected for comparing their capability of accurately mapping health levels of the artificial forests. There were three health levels (i.e. healthy, medium dieback, and severe dieback) based on explicit tree crown symptoms. After the IKONOS and OLI images were preprocessed, both spatial and spectral features were extracted from the IKONOS and OLI imagery, and a maximum likelihood classification method was used to identify and map health levels of Robinia pseudoacacia forests. The experimental results indicate that the IKONOS sensor has greater potential for identifying and mapping forest health levels. Furthermore, texture features, especially texture variance, derived from the IKONOS panchromatic band, contributed greatly to the accuracy of classification results, achieving an overall accuracy (OA) of 96% for the IKONOS sensor and an OA of 88% for the OLI 2, which used both OLI spectral and IKONOS spatial features, compared with an OA of 74% for the OLI sensor alone. Our results indicate that the texture features extracted from high resolution imagery can improve the classification accuracy of health levels of planted forests with a regular spatial pattern. Our experimental results also demonstrate that classification of an image with a spatial resolution similar to, or finer than, tree crown diameter outperforms that of relatively coarse resolution imagery for differentiating living tree crowns and understorey dense green grass.
Inter‐annual variation in the topographic controls on catchment‐scale snow distribution in a maritime alpine catchment, New Zealand

Seasonal snow is a globally important water resource that contributes substantially to upland and lowland water resources. As such, there is a need to understand the controls on the spatial and temporal variation in snow distribution. This study meets this research need by investigating the topographic controls on snow depth distribution in the upper Jollie catchment in the Southern Alps of New Zealand. Furthermore, inter‐annual variation in the importance of the topographic controls is examined and linked to variation in the dominant synoptic‐scale weather patterns over a 4‐year period (2007–2010). Through the use of regression trees, the relative importance of the topographic controls on snow depth was shown to vary between the four study years. In particular, elevation explained the greatest amount of variance in 2007 and 2008 and east‐exposure explained the greatest variance in 2009 and 2010. The other wind exposure variables also had a large effect on the snow depth distribution in 2009 and 2010. Differences in the frequency and duration of synoptic weather patterns were physically consistent with the changing importance of these variables. In particular, a higher frequency of troughing events in 2009 and 2010 is thought to be associated with a reduced importance of elevation and greater influence of wind exposure on snow depth in these years. These findings demonstrate the importance of using multi‐year data sets, and of considering topographic and climatic influences, when attempting to model alpine snow distribution. Copyright © 2014 John Wiley & Sons, Ltd.
Competitive Sets for Lodging Properties

This article illustrates the differences in the composition, characteristics, and performance evaluation of competitive sets of hotels determined using two methods—the common product type classification scheme and the less commonly used cluster analysis based on average daily rate (ADR) as the clustering variable. The analysis examined annual ADR, occupancy, and revenue per available room (RevPAR) for a group of hotels in a portion of a single U.S. metropolitan market. The comparison of the two methods shows the following: the average variability of ADR and RevPAR is less for the cluster-based competitors than it is for competitor groups determined using product type; most clusters contain a variety of product types (confirming that competition occurs across product types); most product types are categorized into different clusters; and the average RevPAR difference between the particular hotel and its reference competitive group is less for the ADR-cluster-based reference group than it is for the product type reference group, indicating that the performance of hotels within cluster competitive groups is more similar than in product type competitive groups. Comparing competing hotels based on the two methods can provide information regarding the extent of congruence between the hotel’s intended competitive position and its position as seen by customers.
Origine et devenir de la matière organique des sédiments de mangroves de Guyane française. - Précurseurs, Environnements de dépôt, Processus de décomposition et Relation avec les métaux lourds –

L'originalite des mangroves de Guyane resulte de leur association avec la ceinture sedimentaire mobile se developpant de l'Amazone a l'Orenoque. Cette zone cotiere tropicale se caracterise par des remaniements sedimentaires importants et extremement rapides. Une double problematique s'imposait, avec les conditions de stockage de la matiere organique (MO) dans les sols de mangroves, et l'etude de ses interactions avec la fraction minerale. Cette etude nous a permis de : i) determiner les relations entre geochimie du substrat et parametres externes ; ii) identifier les relations entre evolution des populations vegetales de la mangrove et composition des MO particulaires et dissoutes ; iii) identifier les processus precoces de la diagenese organique, ainsi que des chemins et des produits de decomposition de la MO ; iv) determiner l'extension de la contamination en metaux lourds, ainsi que l'impact de la diagenese organique et des processus d'oxydo-reduction sur le comportement des metaux.
Preservation of detrital shocked minerals derived from the 1.85 Ga Sudbury impact structure in modern alluvium and Holocene glacial deposits

Detrital shocked minerals can provide valuable residual records of eroded impact structures. Recent studies have reported shocked minerals in modern alluvium in a subtropical climate from the deeply eroded 2.02 Ga Vredefort Dome impact basin in South Africa. To evaluate the detrital shocked mineral record at a large impact structure in a temperate setting with a Holocene glacial erosional history, we investigated ∼4000 detrital zircons and ∼20,000 quartz grains at the less-eroded 1.85 Ga Sudbury Basin in Ontario, Canada, for the presence of shocked sand grains. Modern alluvium from rivers within and outside the basin, and Holocene glaciofluvial sands (eskers and outwash deltas) across the basin were investigated for shocked minerals. Shocked zircon and/or quartz were found in all modern rivers and most Holocene glacial deposits within, but not outside, the basin. Petrography and scanning electron microscopy (SEM; backscattered electron [BSE]; cathodoluminescence [CL]) imaging and analysis (energy-dispersive X-ray spectroscopy [EDS], electron backscatter diffraction [EBSD]) were used to document shock microstructures. Of the total detrital zircons surveyed, ∼3% (118/3978) were identified as shocked; Holocene samples contained higher average percentages of shocked zircon (63/1361, or 4.6%, with a high of 29%) compared to modern alluvium (55/2617, or 2.1%, with a high of 6%). EBSD analysis revealed a range of shock microstructures, including planar fractures, deformation microtwins, and crystal plastic deformation. At Sudbury, detrital shocked quartz is rare compared to zircon; only 15 grains (∼0.08%) were identified, all with decorated planar deformation features (PDFs). These results demonstrate that a detrital shocked mineral record exists at a large impact basin that is in a "youthful" stage of erosion, despite its age. In addition to modern alluvium, our results also identify glaciofluvial eskers and deltas as reservoirs for detrital shocked minerals; glacial episodes thus enhance the dispersal and preservation of shocked detritus in sedimentary systems. Despite physical differences, the observation that the two largest Precambrian impact basins continue to contribute detrital shocked minerals 2 b.y. after impact suggests that a shocked mineral record of impacts on early Earth should reside in Precambrian siliciclastic rocks.
Artificial Aurora Experiment: Ground‐based optical observations

Ground-based image-orthicon television systems detected five raylike artificial auroras produced by electron beams with maximum energy of 8.7 kev directed downward from a rocket-borne accelerator flown January 26, 1969, from Wallops Island, Virginia. Four rays produced by 1-sec 8.7-kev pulses were observed at two stations separated enough to enable the spatial coordinates of the rays to be determined by triangulation. The lower ends of the observed rays were located at altitudes of approximately 104 to 106 km; the upper ends, ranging from altitudes of 122 to 132 km, were not so well defined. Widths of the artificial auroral rays (130±50 meters) and altitudes of the lower ends are in agreement with calculations of Berger et al. (1970), for which Coulomb scattering in a standard model atmosphere with a magnetic dip angle of 69° is assumed. The observed ray positions were within 0.1° of arc, or approximately 400 meters, of the positions predicted from knowledge of the rocket trajectory and the direction of the local geomagnetic field. From the observed durations of three of these auroras and from other data, it is concluded that the ratio of N2+ first negative to O I 5577 emission was between 3 and 7. The observations show no delay in the arrival of the electron beams and indicate that most or all of the energy entered the atmosphere in a well-confined beam.
Martian surface heat production and crustal heat flow from Mars Odyssey Gamma‐Ray spectrometry

Martian thermal state and evolution depend principally on the radiogenic heat‐producing element (HPE) distributions in the planet's crust and mantle. The Gamma‐Ray Spectrometer (GRS) on the 2001 Mars Odyssey spacecraft has mapped the surface abundances of HPEs across Mars. From these data, we produce the first models of global and regional surface heat production and crustal heat flow. As previous studies have suggested that the crust is a repository for approximately 50% of the radiogenic elements on Mars, these models provide important, directly measurable constraints on Martian heat generation. Our calculations show considerable geographic and temporal variations in crustal heat flow, and demonstrate the existence of anomalous heat flow provinces. We calculate a present day average surface heat production of 4.9 ± 0.3 × 10−11 W · kg−1. We also calculate the average crustal component of heat flow of 6.4 ± 0.4 mW · m−2. The crustal component of radiogenically produced heat flow ranges from <1 mW · m−2 in the Hellas Basin and Utopia Planitia regions to ∼13 mW · m−2 in the Sirenum Fossae region. These heat production and crustal heat flow values from geochemical measurements support previous heat flow estimates produced by different methodologies.
A GIS-Based Approach to Evaluating Changes in Wetland Areal Extent and Structure Between 1926 and 1999 for Selected Hydrological Sub-Basins in Pinellas County, Florida

A GIS-based study was undertaken comparing wetland coverages in 1926 and 1999 in selected sub-basins within Pinellas County, Florida, one of the most highly urbanized counties in south-central Florida with almost 50% of the existing land area developed into industrial, commercial or residential land uses (Pinellas County Planning Department, 2002). Wetlands were digitized from rectified 1926 aerials and classified according to the FLUCCS classification system. Wetland coverage for the 1999 data set was extracted from FLUCCS 1999 land use coverage provided by the SWFWMD, and topology for both the 1926 and 1999 wetland and surface waters were created. Statistical and spatial analysis was then performed on the vector feature class layers to determine net wetland loss and gain, by watershed, within the sub-basin study area. Results indicate that substantial and statistically significant net losses in areal extent occurred between the 1926 and 1999 study time frames in most sub-basins for freshwater forested, freshwater herbaceous, saltwater herbaceous, non-vegetated wetlands and in total wetland areal extent. Both open water and upland exhibited statistically significant net increases in areal extent over the same time period. Losses are directly attributable to human-activity such as excavation, ditching, draining, and filling. 1 Chapter One: Resarch Objectives and Development History of Pinellas County
Early Permian Foraminifera from Eastern Himalaya and their palaeobiogeographic significance

Foraminiferal assemblage from Permian rocks of Eastern Himalaya, India are recorded for the first time. Twenty-two genera and twenty-eight species are documented from the Garu Formation, Eastern Himalaya. The foraminiferal assemblage supports previous age determinations based on megafauna. The distinctive foraminiferal assemblage from India supports the recognition of Australian and Afghanistan-Indian provinces in the Early Permian Austral realm. An appreciable number of common species in these provinces is indicative of close geographic links.
Ductile shear zones beneath strike-slip faults: Implications for the thermomechanics

We have carried out two-dimensional (2-D) numerical experiments on the bulk flow of a layer of fluid that is driven in a strike-slip sense by constant velocities applied at its boundaries. The fluid has the (linearized) conventional rheology assumed to apply to lower crust/upper mantle rocks. The temperature dependence of the effective viscosity of the fluid and the shear heating that accompanies deformation have been incorporated into the calculations, as has thermal conduction in an overlying crustal layer. Two end-member boundary conditions have been considered, corresponding to a strong upper crust driving a weaker ductile substrate and a strong ductile layer driving a passive, weak crust. In many cases of practical interest, shear heating is concentrated close to the axial plane of the shear zone for either boundary condition. For these cases, the resulting steady state temperature field is well approximated by a cylindrical heat source embedded in a conductive half-space at a depth corresponding to the top of the fluid layer. This approximation, along with the application of a theoretical result for one-dimensional shear zones, permits us to obtain simple analytical approximations to the thermal effects of 2-D ductile shear zones for a range of assumed rheologies and crustal geotherms, making complex numerical calculations unnecessary. Results are compared with observable effects on heat flux near the San Andreas fault using constraints on the slip distribution across the entire fault system. Ductile shearing in the lower crust or upper mantle can explain the observed increase in surface heat flux southeast of the Mendocino triple junction and match the amplitude of the regional heat flux anomaly in the California Coast Ranges. Because ductile dissipation depends only weakly on slip rate, faults moving only a few millimeters per year can be important heat sources, and the superposition of effects of localized ductile shearing on both currently active and now inactive strands of the San Andreas system can explain the breadth of the heat flux anomaly across central California.
Coastal shell middens of the Abydos coastal plain, Western Australia

Middens and mounds dominated by Anadara granosa began to be formed on the Abydos Coastal Plain sometime between 4400 and 5300 calibrated years before present, and while mounds appear to have ceased forming some 1800-1600 years ago, middens continued to form until the early twentieth century or later. In some cases, the earliest of these middens and shell mounds formed on top of older middens from which Anadara granosa is totally absent, and in which Terebralia spp. (while occurring in relatively low concentrations) is the dominant shell species. Anadara granosa dominated middens (sensu lato) occur in a variety of forms across the landscape, including large shell mounds, earth mounds (or mounded shell middens), lenses of shell eroding out of well-developed dunes, and undifferentiated surface shell scatters. The large number of middens which occur throughout the region from the mid Holocene, and the volume of shell represented by these sites, point to the occurrence of significant economic and social changes from the mid to late Holocene. The Abydos Coastal Plain experienced increasing aridity, and, as a result, increased resource stress during the mid-Holocene. We suggest that the large, single species Anadara granosa middens were occupied during regular periods when large groups of Aboriginal people undertook ceremonial activities after the wet season, when resources were abundant. Changes apparent in the archaeological record, including the occurrence of large numbers of Anadara granosa dominated middens and shell mounds, increased establishment of archaeological sites and increased complexity and distance of exchange systems, came about as a result of social, economic and logistical restructuring. This in turn was the result of the effects of resource stress on local Aboriginal people over the course of the mid to late Holocene.
Statistics of Breaking Waves Observed as Whitecaps in the Open Sea

Abstract Conventional observations of waves carried out with a buoy in open sea conditions were supplemented with simultaneous visual observations of whitecaps to identify breaking events in the buoy records. A statistical wave-by-wave analysis of these records indicates that such seemingly obvious parameters as wave steepness or wave asymmetry cannot be used to separate breakers from nonbreakers and the breaking occurs at wave steepness values much less than the theoretically expected steepness of a limiting wave. The observed fraction of breaking waves varied from about 0.10 to about 0.16, depending on wind speed. Two-thirds of the breaking waves were breaking in one-third of the wave groups for which a Hrms-threshold definition was used.
An EPR study on mollusk shells from loess-paleosol sequences in the Loess Plateau, central China

Electron Paramagnetic Resonance (EPR) analysis was employed to extract paleoclimatic information from mollusk shells taken from the Luochuan section located on the Loess Plateau of central China. The results show that the EPR spectrum of Mn2+ in mollusk shells is complicated and consists of two sets of six hyperfine lines of Mn2+ that arise from two non-equivalent Mn2+ sites in aragonite. There is no obvious inconsistency of EPR spectral intensities among different species of modern mollusks at Luochuan area; the magnitude of EPR spectra intensities of mollusk shells is correlative with the Mn2+ concentration of the environments. The EPR signals from mollusk shells taken from the loess, which is considered to be formed in the cold and dry glacial environment, are stronger than those from the paleosol deposited under the warm and humid interglacial condition suggesting that the Mn2+ available for mollusks in a cold climate is higher than in a warm climate. We propose that during the glacial period, the mollusks lived in a relatively reductive soil environment with more Mn2+ while during the interglacial period its environment was more oxidizing with less Mn2+. This result provides direct evidence that the loess-paleosol interlayers came into being under alternating redox conditions resulting from fluctuating paleoclimate. The analysis of the EPR spectra of mollusk shells serves as a new tool for retrieving climatic information from the mollusk records.
Trends in the upper atmosphere and ionosphere: Recent progress

The upper atmosphere and embedded ionosphere respond to increasing concentration of greenhouse gases and other drivers of long‐term changes and trends. In this paper, the progress reached in investigations of long‐term trends in the upper atmosphere and mesosphere in the last 2 years is briefly summarized. First information appeared about trends in electron temperature (positive trend), thermospheric neutral wind (complex pattern), and total electron content (nonnegative trend). Some new information created partial apparent discrepancies, particularly in the case of ion temperature trends. The quantitative discrepancy between observation‐based and model‐based trends in mesospheric temperatures and in polar mesospheric clouds has largely been removed. The first observations of trends in CO2 concentration in the lower thermosphere suggest a way how to reduce the observation‐model difference in the thermosphere and ionosphere. The scenario of trends in the upper atmosphere and ionosphere is now more complete than it was 2 years ago, but still some gaps and discrepancies occur for further investigations.
Subcentering and Commuting: Evidence from the San Francisco Bay Area, 1980-1990

The dominant spatial trend in U.S. metropolitan areas during the fast-growing 1980s was decentralization of employment. Between 1980 and 1990, the number of jobs in U.S. metropolitan areas increased by 49.2 percent outside of central cities compared to 13.1 percent within them. In all, two-thirds of all metropolitan job growth occurred outside of central cities during the 1980s (Hughes, 1992).