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A flash flood is one of the hazardous phenomena, especially in dry regions. In Saudi Arabia, Jazan Province experiences data scarcity especially historical hydrological data and a lack of studies related to flash flood analysis and the rainfall and runoff interrelationship. Thus, this research aims to study the rainfall-runoff inter-relation, predict flash floods, and to map the risk areas in Jazan Province by the geological, geomorphological, and hydrogeological characteristics along with digital elevation model (DEM), watershed modeling system (WMS) and HEC-HMS models. Jazan Province encompasses 25 drainage basins, receiving a considerable amount of rainfall (ranging from 100 to 500 mm) (August, October-November, March) which intermittently cause strong and destructive flash floods. The DEM was used for delineating the catchment (drainage basins) parameters. Physiographic parameters of the catchments have been analyzed for mapping the hazard degree of the flash flood strength. Further, basins with high hazard degrees of flash floods were selected to assess rainfall-runoff inter-relation using the HEC-HMS models, GIS, and morphometric parameters. Forty %, 8%, 52% of the study area are high, medium, and low hazard degrees of flash floods, respectively. The groundwater recharge in the study area was calculated through the integration of satellite image analysis, SWAT and GIS techniques and it ranges from 0.002 mm/km2/year to 8 mm/km2/year with an average of 2.5 mm/km2/year. Rainfall-runoff inter-relation of study basins, assessed based on the integration of WMS and HEC-HMS models, indicates that the resulting runoff volume ranges from 18.5 × 106 m3 to 473.1 × 106 m3 at a recurrence period of 5 and 100 years at rainfall events of 65 mm and 116.8 mm, respectively. [ABSTRACT FROM AUTHOR]

Activity concentrations of 226Ra, 232Th, and 40K were measured in soil samples from several areas of Garhwal Himalaya, Northern India, by gamma-ray spectrometry. In this region, which extends around the Himalayan Main Central Thrust, a tectonic line that separates several geological provinces, background levels of natural terrestrial radiation were assessed. The maximum levels of radium, 285 Bq/kg and 136 Bq/kg, respectively, were found in the Budhakedar and Uttarkashi regions, exceeding the world average value of 35 Bq/kg. The mean radiation levels were found to be different between the areas, which reflects the geological diversity in the region. The overall absorbed dose rate owing to radionuclide presence in the Uttarkashi area ranged from 79 to 188 nGyh−1, with an average of 118 nGyh−1. That is more than UNSCEAR's world-populated weighted average value of 59 nGyh−1. The present investigation indicated that the absorbed dose rates are greater in Uttarkashi and Budhakedar than in other places. The multiple comparison analysis between geology and absorbed dose rate shows that the geology of Uttarkashi and Budhakedar are statistically similar. According to several hazard indices, terrestrial background radiation is not of radiological concern in the investigated region. [ABSTRACT FROM AUTHOR]

In this research, we figure out the lithospheric structures of the western U.S. and assess its tectonic implications with a high resolution using dense gravity data. Gravity data with high spatial resolution enables detailed mapping capabilities, overwhelming other geophysical data. To investigate the physical basis for support of topography in the western U.S., we employed the parker-Oldenburg algorithm to gravity to calculate the depth to Moho. The estimated depth to Moho shows an excellent spatial correlation with the physiographic provinces in the study area following an eastward thicking pattern. Moho of the stable craton reaches 50 km, whereas the western margin shows a shallow Moho of 20 km. Moreover, to assess the tectonic implication of Moho in the study area, we calculated the crustal compensation load to evaluate the isostatic state in the study area. The calculated compensation loads provide isostatic compensation for large-scale crustal structures, such as the broad, elevated Basin and Range Province. To assess the contribution of the crust and mantle to the topographic deformation in the study area, we calculated the crust topography and mantle topography. The Wyoming Craton and Great Plains have negative mantle topography values, contrasting with the relatively constant values in the southern Rockies, Colorado Plateau, and Basin and Range. Crustal topography reveals significant crustal support from the southern Rockies and the Wyoming craton. In addition, we estimated the lithospheric mantle thickness and the depth of the Lithosphere–Asthenosphere Boundary (LAB); the mantle thickness has values reaching 90 km at the stable eastern craton with LAB depth reaching 140 km. This research demonstrates the effect of the tectonic regime on the study area and the implications of this tectonic on the lithospheric structures with a high spatial resolution of a few hundred meters. [ABSTRACT FROM AUTHOR]

The lithology of the roof of the mining roadway is compound and the thickness of each layer varies considerably, and it is disturbed by dynamic load all the year round. The above factors has caused a huge difference in the stability of the roadway surrounding rock. Taking the 11,020 lower tunnel of a mine in Henan Province as the engineering geological background, using on-site investigation, formula derivation, numerical simulation and other methods, the composite roof roadway model group was established to study the deflection evolution characteristics of the surrounding rock under dynamic load disturbance, and summarize the plastic zone of the surrounding rock of the roadway Deformation and evolution of roof surrounding rock to evaluate the stability of surrounding rock with different roof structures. The research results show that the change of the roof surrounding rock structure will also lead to the change of the center deflection of the roadway roof. Therefore, the center deflection of the surrounding rock of various roof composite structures is different, and the deflection is the most direct indicator of the stability of the surrounding rock. The center deflection ( ω 0 ) of the soft rock type is the largest, the center deflection ( ω 0 )of the upper soft and the lower hard type, and the soft and hard type is larger, and the soft and hard progressive type, thin, hard and thick soft type ( ω 0 ) is the smallest, and the dynamic load The relationship between the magnitude of deflection before and after the disturbance is consistent. By constructing a composite roof roadway numerical model group, using the plastic failure zone of the roadway as the evaluation standard, the surrounding rock stability is evaluated and divided, and then the cross-point field measurement method is used to verify the stability of the surrounding rock on the roof of different composite structures. And the development of composite roof roadway surrounding rock deformation and failure mechanism and numerical simulation method has important theoretical significance and practical value for the analysis and control of composite roof roadway surrounding rock stability. [ABSTRACT FROM AUTHOR]

This study attempted a rock physics template (RPT) based approach to model the impact of mechanical compaction and chemical diagenesis on overall porosity reduction of the Barail Sandstone across the Assam Shelf and Schuppen Belt area. Then, a sensitivity analysis was carried out based on the probabilistic amplitude variation with angle (AVA) approach to study the impact of diagenesis, rock frame constituents, and pore fluids on seismic amplitude response. The RPT depth trend suggests a significant upliftment (~ 2500 m) within the supra-thrust region, while the Assam Shelf and sub-thrust part of the Schuppen Belt were normally compacted throughout the geologic time. The geologically constrained RPT was used to (i) identify the primary process for chemical diagenesis as feldspar dissolution and (ii) estimate total cement, non-contact cement (NCC), and contact cement (CC) values. Laboratory-based analysis of rock samples validated the modeled cement volumes. The RPT-based CC (mode value) estimates were observed as 3%, 5%, and 7%, whereas the NCC varied as 6%, 8.5%, and 11% sequentially from extensional through supra-thrust to sub-thrust regions. The extensional and supra-thrust regions dominantly exhibited class IV AVA for oil and gas saturated rocks mainly due to the presence of coal and the relatively under compacted nature of the Barail Sandstones. A change in AVA class was observed to class II and IIP within the sub-thrust region due to enhanced cementation. The forward modeling revealed that a small amount (2%) of coal presence could potentially change the AVA class from II to IV, and an increase in CC from 5 to 7% could cause the AVA class to change from IV to II. This study efficiently modeled the digenetic effects and seismic amplitude in this tectonically complex region. [ABSTRACT FROM AUTHOR]

The geothermal study in India was initiated in 1962 and in the last six decades it grew in concurrence with the international programmes of geothermal study on several fronts, such as, characterizing heat flow for the major geological units; measuring the thermal conductivity of crustal rocks at ambient and elevated temperatures; arriving at the best mathematical model of thermal conductivity from modal mineralogy; calculating radiogenic heat production for the major rock formations; modeling crustal and sub-crustal thermal structure for the stable regions; calculating mantle temperature constrained with seismic velocities and mantle xenoliths; assessing geothermal energy potential regions and using geothermal observations to estimate past climate changes. Systematic heat flow, thermal conductivity, heat production, and thermal modelling carried out during this period of time led to the refinement of classical thermal models of the continental crust, i.e., from linear-step-exponential heat production model based on linear relationship, to realistic heat production models based on regional geology and regional crustal structure from geophysical studies. In many cases, such studies have also helped in the exploration of geothermal energy potential regions, geo-engineering works and deciphering past climate changes. Future research goals include to study (i) crustal and upper mantle thermal structure in the unexplored geological provinces, active tectonic zones, sedimentary basins, and hot spring areas of the Indian sub-continent, (ii) thermal structure in the adjoining oceanic regions, occurrence of potential geothermal energy resources, (iii) thermal properties of rocks at elevated temperature and their implications in refining lithospheric thermal model, (iv) linkage between geothermal and meteorological records for past climate change. [ABSTRACT FROM AUTHOR]

The article reviews the history and accomplishments of CSIR-NGRI over the past 60 years, related to elucidating the seismic structure of the crust and lithospheric mantle of the Indian shield. Extensive investigations have been carried out in diverse geological and tectonic provinces of India, employing seismic reflection, refraction/wide-angle reflection and passive seismology to decipher (a) the evolution of the Indian plate through geological time, (b) hazard and its mitigation and (c) accumulation and disposition of natural resources. These endeavours entailed the application and development of state-of-the-art methodologies. Synthesis of the results from active and passive seismology reveals that the thickness of the crust varies between 28 and 65 km in the Kachchh and Aravalli regions respectively, consistent with their evolutionary histories. The thickest crust is observed in the western Dharwar craton (WDC) and the shallowest lies in the west coast. The crust in the shield region is mostly thicker, while it is thin beneath the rift zones. Results from coincident reflection and wide-angle seismic reflection studies broadly suggest a three-layered crust with magmatic underplating. Interestingly, the seismic sections traversing the Aravalli fold belt, central Indian suture zone, Dharwar craton and Southern Granulite Terrain (SGT) depict paleo-collision and subduction environments. The diverse character of the Moho, crustal fabrics and structure in different geological provinces indicate that contrasting tectonic environments might have influenced their evolution and support the hypothesis that plate tectonic processes were operative since Neoarchean. The thickness of the lithosphere estimated from receiver functions varies from 80 to 140 km. An undulation in the Lithosphere Asthenosphere Boundary reveals evidence for a flexure on a regional scale, owing to the continental collision of the Indian and Asian plates. However, the lithospheric thickness derived from surface wave dispersion studies is somewhat larger, ranging from 100 to 250 km, with some body wave tomographic studies suggesting it to be ∼400 km, in consonance with the concept of Tectosphere. The thickness values derived from both the methods agree at a few locales such as the Eastern Dharwar Craton, SGT, Cambay, Singhbhum and western DVP. However, a broad disagreement prevails in WDC and northern part of the Indian shield where surface wave tomography reveals the thickness of lithosphere to be 140 to 200 km. [ABSTRACT FROM AUTHOR]

Revealing the evolutionary history of the relationship between humans and Earth will help us understand the spatial and temporal distribution of ancient cultural sites (referred to as ancient sites). This research explored the spatial and temporal distribution of ancient sites in Shaanxi Province (China) from the Han Dynasty to the Tang Dynasty and assessed their correlation with the natural environment and economic patterns using geographic information system (GIS) technologies. The results indicated that (1) the ancient sites in the two periods were mainly centered in Xi'an based on kernel density analysis. The number of ancient sites in the Han to the Northern and Southern Dynasties was greater than that in the Sui and Tang Dynasties. The spatial distribution of ancient sites indicated that more sites are present in northern Shaanxi Province than in the south. (2) The ancient sites in Shaanxi Province were concentrated in the plain area with an elevation of approximately 866 m; the aspects were south, east, and southeast; and the slopes were 0 ~ 3° based on an analysis of the topographic features. (3) The ancient sites were concentrated within 10 km of the river. Fewer ancient sites were distributed with increasing distance from the river, indicating a linear distribution of ancient sites. [ABSTRACT FROM AUTHOR]

High-grade extrauterine serous carcinoma (HGSC) is an aggressive tumor with high rates of recurrence, frequent chemotherapy resistance, and overall 5-year survival of less than 50%. Beyond determining and confirming the diagnosis itself, pathologist review of histologic slides provides no prognostic or predictive information, which is in sharp contrast to almost all other carcinoma types. Deep-learning based image analysis has recently been able to predict outcome and/or identify morphology-based representations of underlying molecular alterations in other tumor types, such as colorectal carcinoma, lung carcinoma, breast carcinoma, and melanoma. Using a carefully stratified HGSC patient cohort consisting of women (n = 30) with similar presentations who experienced very different treatment responses (platinum free intervals of either ≤ 6 months or ≥ 18 months), we used whole slide images (WSI, n = 205) to train a convolutional neural network. The neural network was trained, in three steps, to identify morphologic regions (digital biomarkers) that are highly associating with one or the other treatment response group. We tested the classifier using a separate 22 slide test set, and 18/22 slides were correctly classified. We show that a neural network based approach can discriminate extremes in patient response to primary platinum-based chemotherapy with high sensitivity (73%) and specificity (91%). These proof-of-concept results are novel, because for the first time, prospective prognostic information is identified specifically within HGSC tumor morphology. [ABSTRACT FROM AUTHOR]

The Mesopotamian Plain is part of the Mesopotamia which extends for vast area bigger than the plain. The plain is almost flat and vast lowland, which has clearly defined physiographic boundaries with the other surrounding physiographic provinces. The plain is a huge accumulation geomorphologic unit, where the fluvial, lacustrine, and the Aeolian landforms prevail; the fluvial units being the abundant among others. However, estuarine and marine forms also are developed, but restricted to the extreme southeastern reaches of the plain. The Mesopotamian Plain is covered totally by Quaternary sediments among which the fluvial origin is the most prevailing and more specifically the flood plain sediments. The flood plain sediments are the Holocene in age, whereas the Pleistocene sediments are restricted to alluvial fan sediments and river terraces. The flood plain sediments cover majority of the Mesopotamian Plain, whereas the alluvial sediments are restricted to the northern–eastern, western and southern peripheral parts only. Different geomorphological features indicate the Neotectonic activity in the plain, such as migrations of rivers due to growing of subsurface anticlines. The extreme southeastern part is covered by the tidal flat and sabkha sediments. Marshes and shallow depressions are also covered by the Holocene sediments which are contaminated by the Aeolian sediments. Mesopotamian Plain is a part of the Mesopotamian Foredeep which is a part of the Zagros Foreland Basin including the Zagros Fold-Thrust Belt. It is large continuously subsiding basin since the Upper Miocene (11.62 Ma). The plain shows no structural features on the surface, except the main fault escarpment representing the part of Abu Jir Active Fault Zone. However, the rolling topography, in the northern parts of the plain indicates subsurface anticlines that are still growing up, such as Balad, Samarra, Tikrit and Baiji anticlines indicating the Neotectonic activity. Moreover, many buried subsurface anticlines are present in different parts of the plain. All of them are growing anticlines and have caused continuous shift to Tigris and Euphrates rivers and their distributaries indicating the Neotectonic activities. The minimum and maximum subsidence amounts in the plain since the Upper Miocene are zero and –2500 m, respectively. [ABSTRACT FROM AUTHOR]

The geology and composition of Archean terrigenous sedimentary rocks of the Karelian province (Baltic Shield) are studied in order to establish their positions in the structures of greenstone belts and their role in the provenance composition. It is shown that metaterrigenous rocks from the greenstone belts of the youngest Central Karelian domain, together with intermediate-to-felsic volcanic rocks, compose the main part of the sections, occurring at their bases, and are about 2745 Ma in age. In the belts of the West Karelian domain, metaterrigenous rocks compose the upper parts of the sections, and their age is 2745–2750 Ma. Geological data on the position of metaterrigenous rocks in the belts of the oldest Vodlozero domain also suggest their Neoarchean age. On this basis, it is concluded that metaterrigenous rocks mark the beginning of the Neoarchean stage of crust formation in the Karelian province. According to geochemical data, metagreywackes are predominant among the Archean metaterrigenous rocks of all three domains. At the bases of the sections of some structures, polymictic conglomerates are present with the predominance of tonalite, trondhjemite, and, less often, granodiorite pebbles and with a subordinate amount of igneous rocks of different compositions. Low CaO and Na2O contents and CIA < 55 indicate an insignificant degree of weathering. The Th, Co, Sc, Hf, and La contents indicate a leading role of the TTG-association rocks in the compositions of the sources for all the studied structures. The influence of the basic source was small and affected exclusively Ti, Y, and heavy REE contents in metaterrigenous rocks. The role of komatiites as a source of detrital material was insignificant. [ABSTRACT FROM AUTHOR]

The groundwater resources of basaltic terrains in peninsular India are decreasing rapidly, due to indiscriminate extraction without considering the recharge capabilities of an aquifer. The main focus of the present study is to develop a good perceptive of the groundwater recharge capabilities in basaltic terrains for long term groundwater sustainability. In the present study 3D aquifer solid model of the sub-surface was integrated with surface variables like geomorphology, lineament density, drainage density, slope, land use along with lithology and soil, derived from earth observation (EO) data. This gives a robust platform to find the complex geology of the study area for facilitating artificial groundwater recharge. The methodology adopted provides an opportunity to integrate all the groundwater-related data for a better understanding of the groundwater and surface water interplay in terms of recharge phenomena. The research signified three categories of recharge zones 'highly-suitable'; 'moderately-suitable'; and 'unsuitable'. The recharge zones are found to be in accord with the observed pre and post-monsoon groundwater table signifying the validity of the model. This study would be helpful to delineate groundwater recharge plan in similar geological provinces for ensuring the balance of groundwater resources. [ABSTRACT FROM AUTHOR]

Lead is toxic to humans and wildlife. Most studies of lead exposure of raptors focus on the winter, non-breeding season when they scavenge heavily. We evaluated blood lead concentrations (BLCs) of red-shouldered hawks (Buteo lineatus) during the non-scavenging season in the eastern United States. BLCs of 53 of 70 hawks were above the limit of detection ( x ¯ = 9.25 µg/dL ± 19.81; ± SD). Adult hawks had higher BLCs ( x ¯ = 12.86 µg/dL ± 24.72) than did nestlings ( x ¯ = 3.25 µg/dL ± 2.62; p ≤ 0.001, χ2 = 13.2). There was no difference in BLCs of adult hawks among physiographic provinces but there were differences between urban and non-urban settings (p = 0.04, χ2 = 4.2). Soils and invertebrate hawk prey also had quantifiable lead concentrations. Our work shows that red-shouldered hawks are exposed to lead when not scavenging, and suggests pathways by which these birds may be exposed. [ABSTRACT FROM AUTHOR]

Background and aims: Biocrust morphology is often used to infer ecological function, but morphologies vary widely in pigmentation and thickness. Little is known about the links between biocrust morphology and the composition of constituent microbial community. This study aimed to examine these links using dryland crusts varying in stage and morphology.Methods: We compared the microbial composition of three biocrust developmental stages (Early, Mid, Late) with bare soil (Bare) using high Miseq Illumina sequencing. We used standard diversity measures and network analysis to explore how microbe-microbe associations changed with biocrust stage.Results: Biocrust richness and diversity increased with increasing stage, and there were marked differences in the microbial signatures among stages. Bare and Late stages were dominated by Alphaproteobacteria, but Cyanobacteria was the dominant phylum in Early and Mid stages. The greatest differences in microbial taxa were between Bare and Late stages. Network analysis indicated highly-connected hubs indicative of small networks.Conclusions: Our results indicate that readily discernible biocrust features may be good indicators of microbial composition and structure. These findings are important for land managers seeking to use biocrusts as indicators of ecosystem health and function. Treating biocrusts as a single unit without considering crust stage is likely to provide misleading information on their functional roles. [ABSTRACT FROM AUTHOR]

Metal oxide nanowire-based devices have been widely studied for chemical sensors. Based on the knowledge of the work functions of copper oxide nanowires and metal electrodes, the electrical junction properties such as Schottky barrier height could be modulated by changing the electrode material or decorating the nanowires with another material. Especially for the nanowire decoration process, nanoparticle sputtering or wet chemical synthesis has been used as a post processing method, which is complex and costly. These drawbacks have greatly limited the actual applications of the nanowire-based devices. In this work, a facile one-step thermal oxidation of electroplated interdigitated Cu patterns is proposed for multiple copper oxide nanowire-based device fabrication and a modulation mechanism based on adjusting nanowire density and total area of CuO/Cu-Au interface is discussed. The initial thickness of Cu and the electrode configuration play a deterministic role in the final CuO nanowire morphologies and their junction properties, which is a new finding. [ABSTRACT FROM AUTHOR]

The Mexican Golden Trout ( Oncorhynchus chrysogaster) is a threatened native species inhabiting three river basins in the Sierra Madre Occidental. Despite some efforts from science groups to obtain information about this trout, the Rio Sinaloa and Rio Culiacan basins, to the south, remain the least studied area, compared to the Rio Fuerte basin. To overcome this gap, a survey (2014 to 2015) was undertaken to obtain new records and confirm the presence for historic records in both watersheds. After filtering records for this species, eighteen locations were used to model potential distribution, using the GARP and MaxEnt, including landscape characterization based on hydrologic analysis and satellite imagery classification. Coincidence between models was >85% for a potential distribution area of 4300 km, defined by six bioclimatic and physiographic variables, with the hydrologic network covering 3000 km. To avoid overestimation, the final distribution area included only the 100 m fringe surrounding the drainage network and its associated landscape features. Jackknife resampling was used to validate both the models, successfully predicting more than 80% of the locations ( p < 0.001). The estimated area covers 275 km, mainly defined by second- and third-order streams, at altitudes >2000 m, high water quality (transparent, dissolved oxygen >5 mg L-1; temperature < 26 °C), and was part of a matrix of undisturbed forests. This study provides new findings about this endangered species and new elements for designing appropriate monitoring programs supporting trout conservation and management. [ABSTRACT FROM AUTHOR]

Protecting genetic diversity throughout the range of a species is important for conservation, as doing so provides for long-term evolutionary potential and persistence under a changing environment. Conservation of diversity at the intraspecific level requires identification of all genetically distinct population segments within species; i.e., conservation units (CUs). Silene spaldingii occurs in grasslands of the Columbia Plateau region of western North America and is listed as threatened under the Federal Endangered Species Act. The recovery plan identified five physiographic regions across the range of the species to use as surrogates for genetic CUs. We collected leaf samples from an average of 26 plants from each of 19 of the largest populations across all five physiographic regions and used variable microsatellite and chloroplast DNA markers to determine how genetic variation is distributed across the range of the species and how well physiographic regions reflect population structure within this species. Results of several multivariate analyses clustered our samples into four genetic groups which did not correspond well with the physiographic regions. We observed little genetic differentiation among populations in the main range of the species which encompasses nearly all of four contiguous physiographic regions. However, three other distinct genetic groups were identified: two in the disjunct northeast corner and one at the southeast edge of the main range. Modification of the CUs to reflect the genetic groups rather than the physiographic regions would result in CUs which better reflect historical patterns of population structure. Moreover, use of the genetic units to inform translocation and genetic rescue efforts could improve our ability to mimic natural patterns of gene flow. Our results suggest that physiographic regions may not always be an accurate reflection of population structure for threatened or endangered species. [ABSTRACT FROM AUTHOR]

The main objective of this study was to determine how stream salamander assemblages and species respond to varying levels of impervious surface cover within Maryland's Piedmont physiographic province. We sampled stream salamanders in 21 first-order streams located in watersheds representing a range of impervious surface cover (0-24 %) across the northeastern part of Maryland's Piedmont region. Habitat data, including stream substrate and riparian characteristics, were measured at each site. Eurycea bislineata was the predominant species of stream salamander encountered during this study (> 99 % of individuals) and most of these individuals were larvae (> 92 %). Consequently, statistical analysis was limited to E. bislineata larvae. We were unable to detect a difference in E. bislineata abundances or body mass index's among varying levels of impervious surface cover % or any individual site habitat variables alone. These results suggest that in smaller watersheds within the Piedmont of Maryland, local habitat variables, in conjunction with land use variables, are necessary in determining the abundance and body mass index of E. bislineata larvae populations. This study makes a strong case for halting the over-simplification of the relationship between urbanization and the presence/abundance of stream salamanders. [ABSTRACT FROM AUTHOR]

Traditional ultrastructural characterization of autophagic processes remains an important approach to be used in parallel with molecular genetics, light microscopy, and other methods. The special nature of Caenorhabditis elegans as an object for transmission electron microscopy makes its introduction into autophagy research a challenging task. The basis of the protocol to prepare C. elegans samples for autophagy studies was worked out around the turn of the millennium and has been used since then in my laboratory with some modifications. The method described here enables the user to prepare samples for systematic morphologic as well as morphometric investigations to characterize autophagy with a high but still realistic investment of effort. [ABSTRACT FROM AUTHOR]

Recent years have witnessed growing interest in the critical role of local/regional governance structures in shaping physical land development and associated natural resource management processes. This article investigates how political fragmentation in local governance can affect land use patterns through a watershed-level analysis of population and employment density changes in the Interior Plains, the largest physiographic division of the US. Population density change rates are found to be negatively associated with a higher degree of political fragmentation, while employment density does not show such a clear relationship with political fragmentation. This finding shows that political fragmentation may present significant challenges to land and water resource management, a result consistent with the previous empirical research. [ABSTRACT FROM AUTHOR]

In this study, a Physiographic Soil Erosion-Deposition Model (PSED) is applied for better management of a watershed. The PSED model can effectively evaluate the key parameters of watershed management: surface runoff discharge, suspended sediment transport rate, quantity of soil erosion, and spatial distribution of soil erosion and deposition. A basin usually contains multiple watersheds. These watersheds may have complex topography and heterogeneous physiographic properties. The PSED model, containing a physiographic rainfall-runoff model and a basin scale erosion-deposition model, can simulate the physical mechanism of the entire erosion process based on a detailed calculation of bed-load transportation, surface soil entrainment, and the deposition mechanism. With the assistance of Geographic Information Systems (GIS), the PSED model can handle and analyze extremely large hydrologic and physiographic datasets and simulate the physical erosion process without the need for simplification. We verified the PSED model using three typhoon events and 40 rainfall events. The application of PSED to Chou-Shui River basin shows that the PSED model can accurately estimate discharge hydrographs, suspended sediment transport rates, and sediment yield. Additionally, we obtained reasonable quantities of soil erosion as well as the spatial distribution of soil erosion and deposition. The results show that the PSED model is capable of calculating spatially distributed soil erosion and suspended sediment transport rates for a basin with multiple watersheds even if these watersheds have complex topography and heterogeneous physiographic properties. [ABSTRACT FROM AUTHOR]

Present changes in the regime and structure of mouths of rivers, which empty into the Caspian Sea, are discussed. The similarities and differences of these processes at the mouths of different rivers of the Caspian Region were revealed. Assessment was made of the impact of changes in river water runoff and sediment load and in the Caspian Sea level as well as the nearshore zone relief and local hydraulic engineering activities on the processes under study. Anomalous features of the processes occurring at the mouths of the Volga and Terek rivers were revealed and explained. Hydrological and morphological processes typical of the present mouths of the rivers of Ural, Sulak, and Kura were revealed; these processes could be accepted as universal and possible analogs in assessing the expected changes at the mouths of other rivers in Russia and the world in the XXI century. [ABSTRACT FROM AUTHOR]

Purpose: This paper investigates soils and sediments from the eastern Padanian Plain (northern Italy) in order to delineate the physiographic evolution of the area. Materials and methods: We present new geochemical, mineralogical and textural analyses of alluvial sediments collected from a 13-m-deep section located a few kilometres south of Ferrara. The chronology of the related depositional events is provided from C dating of tree trunks buried at depths of ca. 9 m and organic matter from the underlying horizons. Results and discussion: The data indicate that (1) the upper part of the sequence (down to depths of 9 m) includes sediments characterized by low nickel-chromium (Ni-Cr) concentrations ascribed to the alluvial deposits of the river Reno, deposited in the last 400 years; (2) buried soils (depths of 9-10.5 m) developed on Ni-Cr-rich sediments related to the river Po; and (3) the deeper facies (depths of 10.5-13 m) are CaCO-free and characterized by higher amounts of organic carbon, sulphur and arsenic, reflecting episodic lacustrine/marsh environments. These wetlands probably developed in the area during the Iron and Roman ages, persisting up to the Middle Ages. Conclusions: The data provide a contribution to the understanding of the evolution of the river network during the last 3,000 years and provide insights on the related paleohydrological framework that can be useful for geographical and historical reconstructions of the area. Results highlight the importance of investigating alluvial sediments to elucidate (1) fluctuations of environmental conditions and (2) anthropogenic impacts on the natural landscape. [ABSTRACT FROM AUTHOR]

Review of morphologic, morphometric and compositional data from Mars suggests that volcanism in the early Hesperian Syrtis Major edifice was predominantly ultramafic, in contrast to the abundant basaltic volcanism of the Hesperian to Amazonian Tharsis and Elysium provinces. Comparisons of edifice characteristics between Syrtis Major and the large, circum-Hellas Noachian to Hesperian volcanoes suggest that these structures may also be formed by ultramafic volcanic activity. The data suggest that a global scale magma compositional change occurred on Mars during the late Hesperian. The occurrence of widespread ultramafic volcanism suggests that a high degree of partial melting in a relatively hot mantle characterized Mars' early thermal history, conditions that may be analogous to those that prevailed in the Archean Earth. [ABSTRACT FROM AUTHOR]

The broadening and deepening of Europe as a macro-region impels processes of expansion, contraction and transformation in sub-regions positioned within the EU and across the EU's border. Recent arguments stress the idea of regionalization as a multi-layered process. Using Northern Europe as a study site, three such layers are explored: territorially bounded regionalization in the voting patterns of the Eurovision Song Contest, networked regionalization in the membership of intergovernmental organizations, and fluid regionalization in the geography of language. The associated regionalization processes are explained and visualized using mixed methodologies. Across these three layers of regionalization we can see the persistence of a Scandinavian core, but various territorial, networked and fluid forms of regionalization are stretching and pulling at the edges of Nordic regionalizations. [ABSTRACT FROM AUTHOR]

A large multi-institutional nearshore field experiment was conducted at Truc Vert, on the Atlantic coast of France in early 2008. Truc Vert'08 was designed to measure beach change on a long, sandy stretch of coast without engineering works with emphasis on large winter waves (offshore significant wave height up to 8 m), a three-dimensional morphology, and macro-tidal conditions. Nearshore wave transformation, circulation and bathymetric changes involve coupled processes at many spatial and temporal scales thus implying the need to improve our knowledge for the full spectrum of scales to achieve a comprehensive view of the natural system. This experiment is unique when compared with existing experiments because of the simultaneous investigation of processes at different scales, both spatially (from ripples to sand banks) and temporally (from single swash events to several spring-neap tidal cycles, including a major storm event). The purpose of this paper is to provide background information on the experiment by providing detailed presentation of the instrument layout and snapshots of preliminary results. [ABSTRACT FROM AUTHOR]

The article discusses the gold-bearing potential and geological-structural characteristics of the Amur Province's Lower Selemdzha cluster in Russia. It states that gold mineralization creates paragenesis with dikes of dioritic porphyrites, porphyries, and granite of the Lower Cretaceous Burinda complex. It says that the Lower Selemdzha cluster is near to gold-polymetallic and gold-ore deposits in the province. It mentions that the gold fineness in the Lower Selemdzha cluster's placers varies from 810% to 950% and gold particles have several shapes including crystalline, platy, and clotty.

Detailed analyses of habitat associations with rare species are typically constrained by limited sample size and the availability of habitat data. The dense spatial coverage of stream sampling by the Maryland Biological Stream Survey provides ample data to quantitatively examine correlations between habitat and rare species distributions. The shield darter, Percina peltata, has a widespread distribution on the Atlantic Slope of the United States, but is uncommon throughout its range in Maryland. Associations of in situ physical habitat, water chemistry, and alterations in landscape with shield darter presence in the Eastern Piedmont physiographic province in Maryland were examined. Shield darter occurrence was associated with larger sized streams in concordance with the species' known ecology. Shield darter distribution was further associated with stream segments with deep riffle habitats with diverse velocities, low concentrations of chloride and sulfate, low levels of urbanization in upstream catchments, and several pollution intolerant fish species. Although the exact mechanism of the effects is not clear, results indicate that the shield darter is sensitive to urban development and habitat and water quality alteration that typically accompanies urbanization. Shield darter conservation in Maryland necessitates the protection and restoration of minimally urbanized watersheds where they are known to occur. The results from this study indicate that habitat information on rare species may be important in elucidating important habitat associations that are not evident via examination of community level data. [ABSTRACT FROM AUTHOR]

This study has been carried out for Sonar basin of Ken River system in the Madhya Pradesh. The study was aimed at devising a suitable method for assessment of vulnerability to drought. Analysis of annual and seasonal rainfall records for the period from 1901-2007 revealed that the study basin had faced drought condition with an average frequency of once in every 5 years. The maximum rainfall deficiency recorded in the basin was of the order of −68% in 1979. Recently, drought conditions prevailed in the study basin in the years 2006 and 2007 with annual rainfall deficiency of −35% and −43%, and Standardized Precipitation Index (SPI) values as −1.14 and −1.24 respectively. The paper presents a method for spatially representative depiction of vulnerability to drought using multiple indicators in Sonar basin. These indicators include topography characteristics, land-use types, soil types, relative availability of surface water and groundwater, water demand and utilization and the rainfall departures from corresponding mean values. Spatial information of above indicators was categorized in to various sub classes and maps were prepared in spatial domain using Geographic Information system (GIS). Different layers of above independent indicators and rainfall deficiency have been integrated using a weighing scheme. Thus, the integrated values of weights of various indicators have been computed on 100 × 100 m grid scale in spatial domain and maps have been prepared to represent integrated vulnerability to drought. For rationalization of the approach drought vulnerability Index (DVI) for each grid has been calculated. The DVI has been defined as the ratio of sum of the weights of factors to the sum of their maximum weight values. The results have been validated with intensive field surveys. The proposed method represented drought vulnerability scenarios in the Sonar basin appropriately. It is hoped that this method may set a better direction for the studies on drought monitoring and mitigation. [ABSTRACT FROM AUTHOR]

Chemical studies on 19 lakes of the Argentine sector of the Patagonian Tierra del Fuego Island were performed. These lakes are placed in two geological provinces, Extra Andine (northern) and Fueguian Cordillera (southern). Range of the results obtained, pH (5.80–8.60), TDS (29.5–10,232 mg/l), ionic composition (from calcium bicarbonate to sodium chloride type), Secchi disc depth (0.05–12 m), total inorganic nitrogen (20–237 μg N/l), orthophosphate (5–498 μg P/l), total phosphorus (5–3,800 μg P/l) and chlorophyll a (0.1–63.0 μg/l), indicated the presence of a wide variety of aquatic ecosystems. According to Gibbs model, the mechanisms that control the water chemistry are mainly rock dominance and evaporation–crystallization processes. [ABSTRACT FROM AUTHOR]

Abstract  The nature of shallow aquifers and the impacts of seawater intrusion in small islands within the Pacific Ocean are reviewed. Many Pacific islands rely on shallow fresh groundwater lenses in highly permeable aquifers, underlain and surrounded by seawater, as their principal freshwater source. It is argued here that, in small islands, the nature of fresh groundwater lenses and their host aquifers coupled with frequent natural and ever-present anthropogenic threats make them some of the most vulnerable aquifer systems in the world. A simple steady-state approximation is used to provide insight into the key climatic, hydrogeological, physiographic, and management factors that influence the quantity of, and saline intrusion into freshwater lenses. Examples of the dynamic nature of freshwater lenses as they respond to these drivers are given. Natural and human-related threats to freshwater lenses are discussed. Long dry periods strongly coupled to sea surface temperatures impact on the quantity and salinity of fresh groundwater. The vulnerability of small island freshwater lenses dictates careful assessment, vigilant monitoring, appropriate development, and astute management. Strategies to aid future groundwater sustainability in small islands are presented and suggested improvements to donor and aid programs in water are also advanced. [ABSTRACT FROM AUTHOR]

Pan and Malaise traps have been used widely to sample insect abundance and diversity, but no studies have compared their performance for sampling pollinators in forested ecosystems. Malaise trap design and color of pan traps are important parameters that influence insect pollinator catches. We compared pan trap (blue, yellow, white, and red) and Malaise trap catches from forests in three physiographic provinces (Piedmont, Coastal Plain, and Blue Ridge) of the southeastern United States. Similarities in trap performance between sites were observed with blue pan traps being most effective overall. Our results showed that various pollinator groups preferred certain pan trap colors and that adding color to Malaise traps influenced insect pollinator catches. However, pan traps generally caught more pollinators than Malaise traps. Because of their low cost and simplicity, using several colors of pan traps is an effective way to sample relative abundance and species richness of flower-visiting insects. [ABSTRACT FROM AUTHOR]

Mites in the genus Tropilaelaps are parasites of social honeybees. Two species, Tropilaelaps clareae and T. koenigerum, have been recorded and their primary hosts are presumed to be the giant honeybees of Asia, Apis dorsata and A. laboriosa. The most common species, T. clareae, is also an economically important pest of the introduced Western honeybee (A. mellifera) throughout Asia and is considered an emerging threat to world apiculture. In the studies reported here, genetic (mtDNA CO-I and nuclear ITS1-5.8S-ITS2 gene sequence) and morphological variation and host associations were examined among Tropilaelaps isolates collected from A. dorsata, A. laboriosa and A. mellifera throughout Asia and neighbouring regions. The results clearly indicate that the genus contains at least four species. Tropilaelaps clareae, previously assumed to be ubiquitous in Asia, was found to be two species, and it is here redefined as encompassing haplotypes (mites with distinct mtDNA gene sequences) that parasitise native A. dorsata breviligula and introduced A. mellifera in the Philippines and also native A. d. binghami on Sulawesi Island in Indonesia. Tropilaelaps mercedesae n. sp., which until now has been mistaken for T. clareae, encompasses haplotypes that, together with haplotypes of T. koenigerum, parasitise native A. d. dorsata in mainland Asia and Indonesia (except Sulawesi Island). It also parasitises introduced A. mellifera in these and surrounding regions and, with another new species, T. thaii n. sp., also parasitises A. laboriosa in mountainous Himalayan regions. Methods are described for identifying each species. These studies help to clarify the emerging threat of Tropilaelaps to world apiculture and will necessitate a revision of quarantine protocols for countries that import and export honeybees. [ABSTRACT FROM AUTHOR]

We use morphological image processing for classifying spatial patterns at the pixel level on binary land-cover maps. Land-cover pattern is classified as 'perforated,' 'edge,' 'patch,' and 'core' with higher spatial precision and thematic accuracy compared to a previous approach based on image convolution, while retaining the capability to label these features at the pixel level for any scale of observation. The implementation of morphological image processing is explained and then demonstrated, with comparisons to results from image convolution, for a forest map of the Val Grande National Park in North Italy. [ABSTRACT FROM AUTHOR]

We studied life history and secondary production of a caddisfly scraper, Glossosoma nigrior, in two Alabama streams. Collier Creek, located within the Appalachian Plateau physiographic province, is underlain by sandstone bedrock, while Hendrick Mill Branch is located in the Valley and Ridge physiographic province with limestone bedrock. G. nigrior populations in both streams exhibited trivoltine life histories, which were attributed to the higher water temperature regimes than those found in more northern streams. Mean larval density (556 m−2) and biomass (B) (49.2 mg AFDM m−2) were much higher in Hendrick Mill Branch than Collier Creek (78 m−2 and 6.7 mg AFDM m−2). G. nigrior in Hendrick Mill Branch maintained continuous larval growth and higher larval density than Collier Creek throughout the year mainly due to a greater availability of optimal habitat, a more stable hydrology, and warmer winter water temperature. These factors also resulted in the much higher annual secondary production (P) in Hendrick Mill Branch (965 mg AFDM m−2; P/B = 18.3) than Collier Creek (115 mg AFDM m−2; P/B = 17.9). Gut content analysis revealed that algae (>50%) and detritus (>40%) were the major diet items for G. nigrior, and the majority of secondary production (>80%) was contributed by the consumption of algae. Glossosoma populations play an important role in trophic linkage in these streams with their high production and grazing activities. [ABSTRACT FROM AUTHOR]

This study was undertaken to determine the importance of riparian buffers to stream ecology in agricultural areas. The original Maryland Biological Stream Survey (MBSS) data set was partitioned to represent agricultural sites in Maryland's Coastal Plain and Piedmont regions. ANOVA, multiple linear regression (MLR), and CART regression tree models were developed using riparian and site catchment landscape characteristics. MBSS data were both stratified by physiographic region and analyzed as a combined data set. All models indicated that land management at the site was not the controlling factor for fish IBIs (FIBI) at that site and, hence, using FIBI to evaluate site-scale factors would not be a prudent procedure. Measures of instream habitat and location in the stream network were the dominant explanatory factors for FIBI models. Both CART and MLR models indicated that forest buffers were influential on benthic IBIs (BIBI). Explanatory variables reflected instream conditions, adjacent landscape influence, and chemistry in the Coastal Plains sites, all of which are relatively site specific. However, for Piedmont sites, hydrologic factors were important, in addition to adjacent landscape influence, and chemistry. Both Coastal Plain and Piedmont CART models identified several hydrologic factors, emphasizing the dominant control of hydrology on the physical habitat index (PHI). Riparian buffers were a secondary influence on PHI in the Coastal Plain, but not in the Piedmont. Between 40% and 70% of the variation in FIBI, BIBI, and PHI was explained by the “easily obtainable” variables available from the MBSS data set. While these are empirical results specific to Maryland, the general findings are of use to other locations where the establishment of forest buffers is considered as an aquatic ecosystem restoration measure. [ABSTRACT FROM AUTHOR]

Ecological sensitivity is defined as the ecosystem's reaction to environmental change caused by internal and external factors. The degree of ecological sensitivity varies in spatial dimension depending on the natural and cultural features. Ecological sensitivity analysis is based on basis of mapping these differences. As a result of the analysis, an important data that can be a base for spatial plans at different scales is provided. In accordance with this aim, Denizli province was selected for the study area in this research. The factors affecting sensitivity were determined by the literature survey, which was conducted by considering the characteristics of the study area. In this context, elevation, slope, aspect, the proximity to water surface, land cover, and vegetation coverage were evaluated as natural factors, and the proximity to primary traffic roads and residential areas as cultural factors. Each factor was spatially grouped by means of geographic information systems (GIS) according to the degree of impact on ecological sensitivity. Scale 1 (lowest ecological sensitivity) to 5 (highest ecological sensitivity) was used for the spatial grouping. A analytical hierarchy process (AHP) was applied to weight the factors. The overlay method was used in line with the weighted scores in order to determine the composite ecological sensitivity. As a result of the study, the area of 286.26 sq km (2.37%) as highly and more sensitive, 5267.47 sq km (43.50%) as moderately sensitive, and 6554.56 sq km (54.13%) as mildly and less sensitive was determined. In line with the results, suggestions for protection-utilization balance were developed. [ABSTRACT FROM AUTHOR]

There are small pieces of evidence, suggesting that South America's hydrological cycle is changing, which impacts its water availability and, consequently, the Earth's surface due to its elastic response to the surface mass loading/unloading. Therefore, we analyzed 3 to 15 years of vertical crustal displacements (VCDs) due to mass loadings using 292 Global Positioning System (GPS) stations in South America, which are essential for studies related to tectonic phenomena, for example. Thus, we investigated whether the intra-annual variabilities of the displacements could be reduced using modeled VCDs and inverted displacements from Gravity Recovery and Climate Experiment (GRACE) harmonic solutions (Release 06). The modeled VCDs come from the combination of nontidal atmospheric and ocean loadings with the hydrological loadings from the land-surface model (GLDAS) and reanalysis (MERRA). We found that the highest amplitudes of VCDs of the annual signals are concentrated mainly over the Amazon Rainforest and Brazilian Highlands. However, the results also show different behavior throughout other physiographic provinces of South America, which shows low water capabilities as "sensed" by GRACE and described by the GLDAS and MERRA models. Accordingly, when we disregard the stations over the Andes Mountains and Patagonia in the analysis, the highest reduction in the variability of GPS-observed VCDs is achieved while using GRACE (79% of the sites), MERRA (75% of the sites), and GLDAS (74% of the sites). For these stations, the amplitudes (and phases) of the annual signals depicted by the geodetic sensors generally agree, while those from GLDAS and MERRA explain only approximately 50% of the deformation. However, in the southwest region of South America (between the latitude bands of − 40° to − 30°), GPS annual signals, which reached up to 11 mm, are much larger than those from GRACE and the models due to the existence of lakes that are not resolved in global analysis. These inconsistencies between GPS-observed VCDs and those derived from GRACE and the other models require further investigation, specifically for Chile. [ABSTRACT FROM AUTHOR]

In this study, we developed a physiographic soil erosion-deposition model to simulate sediment yield from a watershed into Agongdian reservoir and sediment flushing to estimate the efficiency of empty flushing. The model was verified using data related to Typhoons Morakot and Fanapi. Thereafter, we calculated the sediment flushing efficiency of empty storage under the conditions of 1- and 2-day storms with seven return periods. The simulated results revealed that the amount of sediment yield from Joushui River watershed was approximately 70% on average, whereas that from Wanglai River watershed was approximately 30%. These results are consistent with those of a government research report, which suggested that the sediment yield figures from Joushui and Wanglai River watersheds were 72 and 28%, respectively. Furthermore, the efficiency of empty flushing was more than 55% when using the shaft spillway pipe, suggesting that the model can be applied to estimate sediment yield and flushing efficiency. [ABSTRACT FROM AUTHOR]

Geomagnetic field data obtained through the INTERMAGNET program are convolved with with magnetotelluric surface impedance from four EarthScope USArray sites to estimate the geoelectric variations throughout the duration of a magnetic storm. A duration of time from June 22, 2016, to June 25, 2016, is considered which encompasses a magnetic storm of moderate size recorded at the Brandon, Manitoba and Fredericksburg, Virginia magnetic observatories over 3 days. Two impedance sites were chosen in each case which represent different responses while being within close geographic proximity and within the same physiographic zone. This study produces estimated time series of the geoelectric field throughout the duration of a magnetic storm, providing an understanding of how the geoelectric field differs across small geographic distances within the same physiographic zone. This study shows that the geoelectric response of two sites within 200 km of one another can differ by up to two orders of magnitude (4484 mV/km at one site and 41 mV/km at another site 125 km away). This study demonstrates that the application of uniform 1-dimensional conductivity models of the subsurface to wide geographic regions is insufficient to predict the geoelectric hazard at a given site. This necessitates that an evaluation of the 3-dimensional conductivity distribution at a given location is necessary to produce a reliable estimation of how the geoelectric field evolves over the course of a magnetic storm. [ABSTRACT FROM AUTHOR]

Reports that the Bureau of Topographic and Geologic Survey has announced the release of Map 67, "Geologic Shaded-Relief Map of Pennsylvania," a colored map of the state showing the bedrock geologic units superimposed on a shaded-relief image. Key features of the map; Use of the regional elevation data in generating the shaded-relief image, which gives the map its three dimensional appearance; Inclusion of two full-color inset maps showing physiographic provinces and sections of the state and general ages of the geologic units.