Miracle-dz/UniFAR-FTUs huggingface dataset:
Modeling within field variation of the compaction layer in a paddy rice field using a proximal soil sensing system

A key characteristic of flooded paddy fields is the plough pan. This is a sub‐soil layer of greater compaction and bulk density, which restricts water losses through percolation. However, the thickness of this compacted layer can be inconsistent, with consequences such as variable percolation and leaching losses of nutrients, which therefore requires precision management of soil water. Our objective was to evaluate a methodology to model the thickness of the compacted soil layer using a non‐invasive electromagnetic induction sensor (EM38‐MK2). A 2.7 ha alluvial non‐saline paddy rice field was measured with a proximal soil sensing system using the EM38‐MK2 and the apparent electrical conductivity (ECa) of the wet paddy soil was recorded at a high‐resolution (1.0 × 0.5 m). Soil bulk density (n = 10) was measured using undisturbed soil cores, which covered locations with large and small ECa values. At the same locations (within 1 m2) the depth of the different soil layers was determined by penetrometer. Then a fitting procedure was used to model the ECa – depth response functions of the EM38‐MK2, which involved solving a system of non‐linear equations and a R2 value of 0.89 was found. These predictions were evaluated using independent observations (n = 18) where a Pearson correlation coefficient of 0.87 with an RMSEE value of 0.03 m was found. The ECa measurements allowed the detail estimation of the compacted layer thickness. The link between water percolation losses and thickness of the compacted layer was confirmed by independent observations with an inverse relationship having a Pearson correlation coefficient of 0.89. This rapid, non‐invasive and cost‐effective technique offers new opportunities to measure differences in the thickness of compacted layers in water‐saturated soils. This has potential for site‐specific soil management in paddy rice fields.
Runoff Production in a Forested, Shallow Soil, Canadian Shield Basin

Storm flow in forested basins on the Canadian Shield is largely supplied by subsurface water; however, mechanisms by which this water reaches the stream remain unclear. Side slope contributions to storm flow were studied using throughflow trenches on slopes in a headwater basin near Dorset, Ontario. Discharge, soil water content, and chemical and isotopic signatures of subsurface water were monitored at each site. Four hypotheses were tested: (1) most flow occurs at the soil-bedrock interface on shield slopes with thin soil; (2) a significant fraction of event water moves vertically to bedrock via preferential flow pathways and laterally over the bedrock surface; (3) relative preevent water contribution to subsurface flow on shield slopes is a function of soil thickness; and (4) a significant portion of event water flux in storm flow from forested basins with shallow soil cover is supplied from side slopes via subsurface flow along the soil-bedrock interface. Hypothesis 1 was confirmed from hydrometric observations during spring and fall rainstorms. Hypotheses 2 and 3 were supported by temporal trends in dissolved organic carbon and 18O in flow at the soil-bedrock interface and by isotopic hydrograph separations (IHSs) of hillslope runoff. Comparison with the streamflow IHS indicated that event water flux from the basin in excess of that attributable to direct precipitation onto near-channel saturated areas could be supplied by flow along the bedrock surface (hypothesis 4). Flow at the soil-bedrock interface on side slopes also contributed ∼25% of preevent water flux from the basin. Much of the event water component of basin storm flow may travel considerable distances via subsurface routes and is not necessarily contributed by surface runoff processes (Horton flow or saturation overland flow). Therefore the assumption that event water undergoes little interaction with the soil during its passage downslope may be unwarranted here.
Dynamic–Thermodynamic Sea Ice Model: Ridging and Its Application to Climate Study and Navigation

Abstract A dynamic–thermodynamic sea ice model with the ocean mixed layer forced by atmospheric data is used to investigate spatial and long-term variability of the sea ice cover in the Arctic basin. The model satisfactorily reproduces the averaged main characteristics of the sea ice and its extent in the Arctic Basin, as well as its decrease in the early 1990s. Employment of the average ridge shape for describing the ridging allows the authors to suggest that it occurs in winter and varies from year to year by a factor of 2, depending on an atmospheric circulation pattern. Production and horizontal movement of ridges are the focus in this paper, as they show the importance of interannual variability of the Arctic ice cover. The observed thinning in the 1990s is a result of reduction in ridge formation on the Pacific side during the cyclonic phase of the Arctic Oscillation. The model yields a partial recovery of sea ice cover in the last few years of the twentieth century. In addition to the sea ice cover.
Pseudomorphs after evaporitic minerals interbedded with 2.2 Ga stromatolites of the Yerrida basin, Western Australia: Origin and significance

Widespread quartz pseudomorphs after evaporitic minerals are interbedded with stromatolites in 2.2 Ga sedimentary rocks in the Yerrida rift basin of Western Australia. These deposits preserve diverse original crystal morphologies that grew displacively either as individuals or as clusters within stromatolitic horizons and associated fine-grained siliciclastic beds. The stromatolites were deposited in shallow-marine, restricted environments. Although evaporitic minerals are largely replaced by quartz, their crystal shapes include lenticular, rosette, needle, and nodular forms, suggesting that they formed from calcium sulfate–rich brines. Textures suggest that replacement by quartz occurred during early alteration of the sediments. Original calcium sulfate minerals such as gypsum or anhydrite are indicated by the morphologies of the pseudomorphs; this concept is supported by anhydrite inclusions in the quartz crystals that form the pseudomorphs, and this finding indicates that calcium sulfate existed in Early Proterozoic sedimentary environments.
Spatial Variability of Morphological Properties at a Florida Flatwoods Site

Soil profiles were described on a grid at 60-m intervals to assess the variability of soil morphological properties in 60 ha of Florida flatwoods. Depths from the soil surface to the spodic and argillic horizons were mapped using field data supplemented with kriged values. In addition, a 120 by 120 m subarea was described at 15-m intervals. The occurrence of a single deep spodic horizon at a few peripheral locations influenced the structure of variograms and contributed to anisotropy. The soil profiles adjacent to these locations exhibited two spodic horizons, one much deeper than the other. The variance structure model for spodic horizon depth in the overall 60-ha site accurately described the variance structure for the subarea. At some sampling locations, neither a spodic nor an argillic horizon was observed. Absence of the argillic horizon was more common than absence of the spodic horizon. Areal discontinuity in the argillic horizon was more extensive than in the spodic horizon. Such discontinuity in the argillic horizon was observed near and between depressional areas. Although the variance structure of depth to the argillic horizon could be described using an anisotropic variogram model, better estimates of depth to the argillic horizon were obtained using variograms of residuals and drift functions.
Characterization of suicide attempts and self-harm by adolescents and adults notified in Santa Catarina, Brazil, 2014-2018*

Objective: To characterize adolescent and adult suicide attempts and self-harm reported in Santa Catarina, Brazil, from 2014 to 2018. Methods: This was a cross-sectional descriptive study with data from the Notifiable Health Conditions Information System. The sociodemographic, clinical and type of self-inflicted violence characteristics among adolescents and adults were compared. Results: Among the 8,859 notifications analyzed, suicide attempts predominated in relation to self-mutilation; self-inflected violence was more frequent in females, those of white skin color and with mental disorders; it occurred more at home, in both age groups. Among adolescents, repeated self-mutilation (83.3%) stood out, while among adults, repeated suicide attempts (50.6%) and suspected alcohol use (18.3%) at the time of violence stood out. Conclusion: We identified high prevalence of attempted suicide among adolescents and adults; the characteristics of violence were similar between the age groups analyzed.
Anisotropic wave propagation and zero-offset migration

In reflection seismology, migration may be defined as the transformation of apparent reflector positions to their true positions. In practice this usually means that diffractions are collapsed and reflector dip angles are changed. When a medium is anisotropic, and the axes of velocity symmetry are tilted with respect to the horizontal, horizontal reflection events migrate laterally as well. The lateral migration of reflections from horizontal layers was studied by constructing an anisotropic scale model representing a medium in which the bedding is inclined to the surface. This situation may be classified as one of transverse isotropy with a tilted axis of symmetry. The elastic parameters of the anisotropic model were recovered by P- and SH-wave transmission measurements carried out to simulate a walk-away VSP. Numerical modelling of a P-wave CMP gather above a horizontal reflector in such a medium indicated that there would be an asymmetrical distribution of reflection points. The zero-offset reflection point was displaced laterally by a distance equal to more than 20% of the depth, and the spread of reflection points was 15% of the depth. The NMO velocity was found to be a function of offset. A zero-offset reflection survey was carried out on the model. The P-wave data were migrated with an anisotropic migration algorithm which may be applied to wavefronts of any shape. On the resulting section, the horizontal reflection features are moved laterally by a distance equal to 20% of the depth back to their correct positions. The lateral displacement of reflections from a horizontal reflector beneath a medium with tilted anisotropic velocity characteristics has significance for the selection of drill locations when such a situation is encountered in the field.
Peroxy radicals as measured in ROSE and estimated from photostationary state deviations

Ambient measurements of peroxy radical concentrations were made using the chemical amplifier (CA) and determined independently from photostationary state deviations (PSSD), NO2 + hv (+O2) ⇌ NO + O3, derived from simultaneous measurements of O3, NO, NO2 and jNO2. The data were collected in the Rural Oxidants in the Southern Environment experiment during 19 days of July 1990. A reasonably good correspondence between the two methods is observed for many of the days, although estimates from the PSSD method for some of the days are higher by as much as a factor of 2. Scatter observed between estimates probably results from several sources: uncertainties in the calibration of the RO2-HO2 instrument, rapid changes in the ozone background, rapid alterations in the solar flux induced by intermittent cloud cover, and imprecisions in making simultaneous measurements of [NO], [NO2], [O3], and jNO2 required for the PSSD method. Possible origins of bias in the two measurement techniques are discussed. Theoretical estimates of the peroxy radical concentrations were made using the measured suite of trace gas concentrations for 2 days, one for which the CA and PSSD estimates of peroxy radical concentrations differed significantly (July 14) and one for which they showed good agreement (July 11). Theoretical estimates for July 11 checked well with the results from both methods. Those for July 14 fell between the GA and PSSD estimates. These results suggest that the PSSD method may have a bias toward higher estimates on some days and/or that the CA method may have a bias for the lower estimates for reasons which are discussed.
Detecting soil information in a predominantly black soil region using Indian Remote Sensing Satellite (IRS-1B) Linear Imaging Self-scanning Sensor (LISS-II) data

Spaceborne multispectral data have been operationally used for deriving information on soil resources since the early 1970s. In this study an attempt has been made to evaluate the potential of the Indian Remote Sensing Satellite (IRS-1B) Linear Imaging Self-scanning Sensor (LISS-II) data for mapping soil resources in part of northern India through a systematic monoscopic visual interpretation approach. Soils were classified up to series level. A strong correlation between the image elements and different categories of black soils has been observed, indicating thereby the potential of such data for providing reliable information on soils in the black soil region.
Revisiting the South Pacific subtropical circulation: A synthesis of World Ocean Circulation Experiment observations along 32°S

Hydrographic data about latitudes 30°–32°S in the Pacific Ocean are presented and used together with direct velocity observations from floats and moorings to investigate the spatial distribution of meridional flow and its associated transports. An initial velocity scheme is developed with reference to the water property distributions that is subsequently adjusted to meet constraints on net mass and dissolved silica transports. The resulting circulation is found to be sensitive to a priori scaling assumptions and differs in detail from past estimates of the flow in this region. Additionally constraining the flow with directly measured time averaged estimates of the velocity from floats and a current meter array significantly reduces the uncertainty in the derived flow field and improves consistency between the velocity and the property distributions. The derived circulation includes a nearly closed bottom-to-deep-water overturning circulation of 16–20 Sv, below a subtropical gyre flow of thermocline and surface waters consisting of nearly distinct Tasman Sea (∼30 Sv) and basin interior (∼10 Sv) circulations and (a prescribed) ∼10±5 Sv of net northward flow to supply the Indonesian and Bering Strait throughflows. On the basis of this circulation scheme, the heat flux divergence for the Pacific north of the P6 line is estimated to be 0.75±0.56 pW (ocean gaining heat from the atmosphere) and the net freshwater divergence is estimated to be 0.1±0.1 Sv (ocean gains fresh water via air-sea exchange and runoff). The former is highly dependent on the strength of the Indonesian throughflow; the latter also depends on the intensity of the lateral subtropical gyre circulation, which is constrained by the float data. Combined with estimates from the Indian and Atlantic Oceans, we find the subtropical Southern Hemisphere oceans transport 0.46±0.38 PW poleward, less than half the poleward heat transport achieved by the subtropical oceans in the Northern Hemisphere.
Scaling and physical thresholds : the case of continental topography

Abstract Thresholds derived from statistical inference are used frequently to detect some properties of geometrical distributions. Here, in the case of continental topography, it is shown that an intrinsic physical threshold with a characteristic dimension exists which must be taken into account before applying any standard analysis. For distances ranging from 100m to 100km, the elevation statistical distribution is well approximated by a standard Brownian surface with a fractal dimension D = 2·5. However, this pattern is unable to explain a global drainage. The hypsornetric curve of watersheds is used as an approximation of a drainage profile. Then dealing with continental wide hydrographic basins, it is shown that beyond a threshold around 150km the large-scaleelevation follows a logarithmic trend constrained by two boundary conditions: the sea level and the tectonic ridge.
Asteroid spectroscopy: Progress and perspectives

Abstract The following discussion is divided into seven major sections. The first section outlines the scientific background and justification for asteroid studies in the context of understanding the formation and early evolution of the solar system. The second section briefly reviews the nature and distribution of the asteroid population. The third section discusses several major unresolved issues in asteroid and meteorite science which can potentially be addressed by asteroid remote sensing investigations. The fourth section outlines the nature and definition of the asteroid taxonomic classes. The fifth section summarizes the existing asteroidal spectral (and other remote sensing) data sets which are used to determine compositions and the techniques employed in the interpretation of such data. The sixth section explores the compositional meaning and diversity of these taxonomic classes and suggests meteoritic analogues for the taxonomic types. The seventh section describes the conclusions—or preliminary results—of several recent asteroid investigations which have focused on particular unsolved issues of the asteroid-meteorite relationship and of the early solar system properties. The final section discusses the overall conclusions and future directions.
XII.—The Genus Pitys, Witham, emend

Few plants of Carboniferous age have appealed so strongly to the scientific observer as the huge woody trunks of a coniferous type that have been discovered from time to time in beds of that system. The appeal has come from different points of view at different times; thus these trees were hailed by Witham (1831, pp. 1–2), Lindley and Hutton (1831, p. xiii), and Hugh Miller (1849, p. 186) as evidence of the existence of higher coniferous plants in abundance during a period to which the current consensus of scientific opinion had assigned only members of the lower plant families, or would admit only an infrequent occurrence of higher forms. These remains were therefore important in discussions concerning the development of plant life, and were cited by Hugh Miller (1849, p. 185) in his attempt to combat the then embryonic ideas of evolution—the recrudescence of Lamarckian ideas—current under the name of “the development hypothesis. ” Miller, however, recognised one significant point, namely, that they represented a land flora as distinct from one occupying a water habitat (1849, p. 202).
Velocity of compressional waves in limestones, marbles, and a single crystal of calcite to 20 kilobars

Velocity of compressional waves in Solenhofen limestone, Oak Hall Quarry limestone, Danby marble, Rutland white marble and a single crystal of calcite (along the c axis) are measured under hydrostatic condition to 20 kb. All measurements show the following characteristics: The velocity rises with increasing pressure to a maximum, falls to a minimum at 15.5±0.5 kb, and rises again with pressure. The measurements are reproducible during the course of lowering the pressure. The peculiar change of velocity at about 15.5 kb is associated with one of the calcite transitions discovered by Bridgman.
Benthic phosphorus regeneration, net primary production, and ocean anoxia: A model of the coupled marine biogeochemical cycles of carbon and phosphorus

We examine the relationships between ocean ventilation, primary production, water column anoxia, and benthic regeneration of phosphorus using a mass balance model of the coupled marine biogeochemical cycles of carbon (C) and phosphorus (P). The elemental cycles are coupled via the Redfield C/P ratio of marine phytoplankton and the C/P ratio of organic matter preserved in marine sediments. The model assumes that on geologic timescales, net primary production in the oceans is limited by the upwelling of dissolved phosphorus to the photic zone. The model incorporates the dependence on bottom water oxygenation of the regeneration of nutrient phosphorus from particulate matter deposited at the water-sediment interface. Evidence from marine and lacustrine settings, modern and ancient, demonstrates that sedimentary burial of phosphorus associated with organic matter and ferric oxyhydroxides decreases when bottom water anoxia-dysoxia expands. Steady state simulations show that a reduction in the rate of thermohaline circulation, or a decrease of the oxygen content of downwelling water masses, intensifies water column anoxia-dysoxia and at the same time increases surface water productivity. The first effect reflects the declining supply of oxygen to the deeper parts of the ocean. The second effect is caused by the enhanced benthic regeneration of phosphorus from organic matter and ferric oxyhydroxides. Sedimentary burial of organic carbon and authigenic calcium phosphate mineral (francolite), on the other hand, is promoted by reduced ocean ventilation. According to the model, global-scale anoxia-dysoxia leads to a more efficient recycling of reactive phosphorus within the ocean system. Consequently, higher rates of primary production and organic carbon burial can be achieved, even when the continental supply of reactive phosphorus to the oceans remains unchanged.
On observing the compositional variability of the surface of Venus using nightside near‐infrared thermal radiation

[1] There are several windows in the near-infrared wavelength range (∼1 μm), in which thermal radiation emitted from the planetary surface penetrates through the thick Venus atmosphere and clouds. In this study we develop an improved method to estimate the surface emissivity on the basis of near-infrared thermal emission from the nightside Venus, which is observed through these windows. A simple radiative transfer model demonstrates that multiple reflection of thermal radiation between the atmosphere (including clouds) and the solid surface has a significant influence on the observed radiance under the condition of Venus, where reflectivity of overlying atmosphere and clouds is high. Thus it is necessary to take the effect of the reflection by the planetary surface into account in order to estimate accurately the variation in the surface emissivity on the basis of near-infrared observation of Venus. The net effect of multiple reflection of surface thermal radiation between the atmosphere and the surface is to significantly reduce the spatial contrast in thermal radiation due to surface compositional variation. The model calculation demonstrates that despite this effect, detection of granitic rocks on the Venus surface using near-infrared windows is feasible. Since granitic and basaltic rocks have dramatically different 1 μm emissivities, granitic rocks are distinguishable from basaltic rocks by ground-based telescopic observation. A Venus orbiter that measures both the near-infrared thermal radiation and the surface altitude with great accuracy will provide us with a reliable surface emissivity map of Venus, which is a very valuable tool to detect granitic (i.e., Earth-like continental) rocks on Venus.