Study Region Research Articles

Atmospheric corrosion of carbon and galvanized steel under high rainfall conditions.

The corrosion rates of carbon steel and galvanized steel according to the ISO 9223 standard, the effect of pollutant contamination and atmospheric aggressiveness under high rainfall conditions in the Chocó department were studied. Carbon and galvanized steel samples, chloride, and sulfur collectors were exposed in three atmospheric stations in three strategic positions covering the Colombian Pacific: Quibdó, Andagoya and Bahía Solano, for different exposure periods (up to 18 months). The structural-micro characterization of corrosion products was evaluated via X-ray diffraction (XRD), Raman spectroscopy and scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy SEM-EDS. The results indicate that all study regions obtained the highest time of wetness category (τ 5). The sulfur-containing pollution (SO2) was categorized as P 0 (rural atmosphere) with average values of P d≤4mg/m2 - day. Bahia Solano station showed the highest chloride deposition rate, reporting an average of 8.3mg/m2-day (categorized as δ1), according to ISO 9223. Due to the extremely high rainfall in the department of Chocó, the results initially suggested hematite formation on carbon steel. After several months, there was a phase transition to lepidocrocite (γ-FeOOH). The formation of γ-FeOOH induces active corrosion on the iron substrate. The zincite phase (ZnO) was observed in the galvanized steel corrosion products. The corrosion rates of carbon and galvanized steel in the location of Quibdó-Colombia were higher than in previous reports. Data analysis reveals that the precipitation variable, which governs the TOW and pollution contaminants, significantly influences the corrosion of these exposed metals.

Managing Demolition Wastes Using GIS and Optimization Techniques

Egypt has experienced vast urbanization and expansion in existing highways, leading to much demolition waste. Construction and demolition waste constitutes around half of the total municipal waste. So, these wastes must be appropriately managed to decrease their negative impacts. As a result, this research presents a framework that automatically detects demolishing wastes’ location and optimizes utilized resources in demolition and transportation processes. It consists of three main components: the GIS module, the optimization module, and the decision-making module. Based on the raster image of the study region, the framework detects existing buildings that should be demolished to enable highways’ expansion. The GIS module is designated to quantify the volume of demolition waste in the studied area using ArcGIS Pro software. The optimization module determines the near-optimum combination of resources involved in the demolition process and waste transportation. These resources include labor crews, excavators, and trucks. The module performs multi-objective optimization using a non-dominated sorting genetic algorithm (NSGA-II). The optimization module considers three objectives in demolition and transportation processes: time, cost, and energy consumption. Finally, the decision-making module is developed to rank the Pareto front solutions. The Entropy Weight Method (EWM) is used to identify the weights of the three criteria. The estimated weights for time, cost, and energy consumption are 38.6%, 17.3%, and 44.1%, respectively. Subsequently, the TOPSIS technique is utilized to normalize, rank, and select the best solution. The proposed framework is applied to an actual case study that involves expanding the ring road project in Cairo to demonstrate its main features.

Petrophysical cobalt exploration indicators in Kuusamo, northern Finland

The increasing global demand for cobalt, a critical green transition metal, encourages the development of improved exploration workflows, as Co typically occurs as a by-product of other metals, and the exploration and processing methods are rarely optimised for it. This paper investigates the possibility of extracting geophysical cobalt exploration indicators from petrophysical properties in Kuusamo, one of the most prominent cobalt-enriched areas in the largest European Co producer, Finland. The study region hosts 20 Au–Co deposits and occurrences classified as orogenic gold deposits with atypical metal association. Two separate mineralization stages have been distinguished: a pyrrhotite-dominated Co-stage and a pyrite-dominated Au–Co stage. The assumption in this study was that Co-enriched samples could be distinguished from Au-enriched samples and host rocks in petrophysical data due to the mineral associations. The investigation used an extensive previously acquired petrophysical and geochemical drill hole dataset from six targets complemented with new thermomagnetic data for magnetic mineral phase detection. The samples were divided into ore classes for the petrophysical data analysis. The results indicate that cobalt’s association with monoclinic pyrrhotite is a key factor for geophysical applications: the high remanent magnetisation characteristic of monoclinic pyrrhotite suggests that Co-enriched ores should typically associate with magnetic anomaly sources. Co enrichment is also related to higher electrical conductivities in comparison to Au. The workflow applied in this study illustrates how key petrophysical parameters can be connected with ore-bearing minerals and rocks, and the results indicate how cobalt could be explored more directly and effectively in the study area.

Assessment of Aquifer Resistivity, Depth, and Thickness using Vertical Electrical Sounding (VES) in Parts of Bori Metropolis for Groundwater Exploration

Groundwater exploration is vital to guaranteeing a reliable water supply in both urban and rural locations. In Bori Metropolis, the growing demand for potable water necessitates a thorough examination of the aquifer system. Therefore, the purpose of this study is to determine the groundwater potential in Bori Metropolis by assessing aquifer resistivity, depth, and thickness using Vertical Electrical Sounding (VES). A total of 13 VES surveys were completed in the study region using the Schlumberger array. The apparent resistivity measurements were analyzed using 1D inversion techniques to determine aquifer depth and thickness. The results showed that aquifer resistivity values ranged from to at depths ranging from to . Aquifer thicknesses ranged from to , indicating a high groundwater potential in the area. The results indicate that the Bori Metropolis area comprises a well-defined aquifer system with a high potential for groundwater extraction. These findings give important information for future water resource management in the region.

Forward modelling of white spruce radial growth at trailing edge demonstrates high plasticity

Climate conditions throughout the 21st century across much of western Canada's boreal forest have been drier than normal leading to significant impacts on forest productivity and tree growth. Determining the limiting factors of radial growth in common boreal tree species under current and future conditions is crucial to reconcile how they will continue to respond to climate change. In this study, we used a network of 26 white spruce tree-ring chronologies south of its natural range as an artificially constructed trailing edge to assess climate-growth relationships and limiting factors by identifying seasonal climate relationships and using the Vaganov-Shashkin Lite (VS-Lite) model, respectively. Analysis revealed that white spruce in the study region is positively correlated to precipitation and negatively associated with temperature from the current and previous growing seasons. VS-Lite showed that moisture was the primary limiting factor in growth across the entire study area. The modelled radial growth from the VS-Lite model showed moderate success (14 of 26 site models were significant) and was more variable than measured tree-ring index values. The model systematically overestimated drought-related impacts on radial growth, especially during the middle portion of the growth season (June–August) indicating white spruce likely employs a conservative approach to carbohydrate storage as the region is much more susceptible to moisture deficits. The outcome of our research illustrates that white spruce may be resilient to hotter, drier conditions through environmental plasticity in the Boreal Plains.

Testate amoebae as paleohydrological indicators in the boreal and subarctic permafrost mires in the western part of the central Siberian Plateau

Carbon storage capacity of peat deposits in permafrost mires is highly sensitive to climate change which effects might be strongly mediated by mire moisture and permafrost. Thus, it is essential to develop appropriate indicator tools of hydrological regime which can be used for monitoring present and past conditions in these mires. We use testate amoebae to investigate their indicator value to water table depth (WTD) and substrate water content (SWC) and to develop transfer functions for quantitative reconstructions of these environmental characteristics in the permafrost mires on the Central Siberian Plateau. In many cased, direct measurement of WTD in permafrost mires are not possible due to the presence of ice, so that SWC can be used as an alternative characteristic. Overall, 330 surface samples were collected in five study regions together with the corresponding environmental measurements. We find that testate amoebae form diverse assemblages with the species structure strongly controlled by WTD and SWC. We developed two testate amoeba-based transfer functions to reconstruct these characteristics based on Modern Analogue Technique which were assessed using leave-one-out and bootstrap cross-validation. We find that both transfer functions have good predictive power (for WTD: RMSEP = 6.8–7.6 cm, R2 = 0.54, for SWC: RMSEP = 2.0–2.3 %, R2 = 0.74–0.76). The ecological preferences of the majority of testate amoebae were similar to those reported by the studies in lower-latitudes, although some hydrophilic taxa were observed in the drier end of the surface wetness gradient. These data represent an important source for improvement of quantitative reconstructions based on subfossil testate amoebae in permafrost mires.

Assessing inter-basin groundwater input to the Verlorenvlei estuarine lake using stable isotopes and hydrochemistry

Study region: Verlorenvlei Catchment (∼1 890 km2) is an agriculture-dominated area (∼43 % per km2) on South Africa’s west coast. This semi-arid region has variable rainfall and high evaporation rates, affecting the three major aquifers and Verlorenvlei – a RAMSAR-listed estuarine lake. Study focus: Natural processes (i.e., extended dry periods and evaporation) and anthropogenic activities (i.e., agricultural expansion and groundwater abstraction) have threatened Verlorenvlei’s ecological functions. Seasonal and spatial changes between the water sources (i.e., direct rainfall, surface water, and groundwater) supporting Verlorenvlei were determined using δ18O and δ2H isotopes and hydrochemical analyses. Inter-basin aquifer contribution was investigated to assist in explaining Verlorenvlei's slow recovery since the recent 2015 – 2018 Western Cape drought. New insights: A proportion of groundwater from outside the topographic and surface-water delineated catchment supports Verlorenvlei during the dry month of April (i.e., G30F Langvlei sub-catchment). Furthermore, Verlorenvlei experiences high evaporation (evaporation best fit line: δ2H = 12.49 x δ18O - 47.68, average δ2H value of 47.1 ‰ and average δ18O value of 7.64 ‰) compared to its feeding rivers. Two sandstone and shale-dominated sub-catchments exhibit overlapping groundwater δ18O and δ2H values and water types to the sub-catchment in the nearest vicinity of Verlorenvlei, suggesting a disproportionately high groundwater contribution from these sub-catchments to Verlorenvlei. Evaluation of Verlorenvlei’s water balance should consider both surface water and groundwater sources, particularly from inter-basin aquifer sources during prolonged droughts.

Remote sensing applied to biophysical parameters and land cover to identify urban heat islands in Recife (PE), Brazil

Urban growth results in several changes, mainly related to demographic, social, economic, and environmental aspects, leading to a new connotation in the use and occupation of land. This new scenario impacts the local energy balance, creating what is called an “urban heat island”. This study aims to investigate the occurrence of urban heat islands in Recife city, the capital of Pernambuco, Brazil, based on the processing of biophysical parameters, the classification of land use and occupation, and surface temperature. The orbital images of the study region were obtained and processed using the Google Earth Engine cloud processing platform from 2013 to 2021. The results showed an increase in areas with greater urban density and a reduction in areas with vegetation. It was realized that in regions with greater urban density, the surface temperature observed was up to 5.20°C higher than in the area with vegetation.

Examination of the potential for geothermal energy in parts of the Benue trough, Nigeria, through the use of high-resolution aeromagnetic data

Aeromagnetic data from nine sheets covering parts of Benue Trough Nigeria were analyzed to identify potential geothermal locations. The aeromagnetic data sheets were analyzed with Oasis Montaj 8.4, Matlab 7.5, Arcmap 10.7.1, and Surfer 13 combined. The centroid depth method was used to spectrally evaluate the depth of high-resolution aeromagnetic data. The findings showed that the research area's geothermal heat flow values range from 88.52259 mW/m2 to 166.2844 mW/m2, while the Curie Point Depth values range from 8.55 km to 16.38 km with a mean depth of 12.2068 km. The Geothermal Gradient values vary from 35.40904 ℃/km to 66.51376 ℃/km with a mean value of 48.85639 ℃/km. The region's mean thermal transfer is 122.1410 mW/m2. It appears that the Curie Point Depth is highest for the lowest thermal transfer values and lowest for the highest thermal transfer values. The study area's heat flow measurements indicate that the crust is oceanic. The comprehensive geothermal data this study provides may aid the study area's exploitation of geothermal energy. Given the extremely high heat flow recorded, there is a likelihood that the studied area has geothermal energy sources. As a result, it was observed that practically the entire study region had substantial heat flow (>80 mW/m2), suggesting the possibility of a geothermal energy source.

Landslide susceptibility evaluation and determination of critical influencing factors in eastern Sichuan mountainous area, China

Landslide susceptibility evaluation and determination of critical influencing factors is a prerequisite for preventing hazardous risks, especially in landslide-prone mountainous areas. However, in densely vegetated Southwest mountainous areas, identifying assessment approach of shallow landslides susceptibility and their major inducing factors is still a huge challenge. To address this challenge, we applied five advanced machine learning models (Logistic Regression Model, Generalized Additive Model, Random Forest Model, Support Vector Machine Model, Artificial Neural Network Model) to assess the spatial distribution of shallow landslide susceptibility, considering several relevant factors that affect landslide occurrence. These factors include geological, topographic and vegetation factors, as well as four new vegetation factors: stock volume, stand density, average tree age, and stand types. Furthermore, we employed SHAP algorithm and Structural Equation Models to quantify the relative importance and explanatory power of these factors on shallow landslide susceptibility and to clarify the interaction mechanisms among various factors in Huaying Mountain. The results shown that Random Forest Model proves to be the most accurate (95.1 %) in assessing the spatial distribution of shallow landslides susceptibility, followed by the Artificial Neural Network model (78.6 %), the Support Vector Machine model (69.8 %), the Generalized additive model (68.1 %) and the Logistic Regression model (67.6 %).The area with high susceptible landslide possibility was 25.3 km2 occupying 14.8 % of the study region, it is mainly distributed in the west of Tianchi Lake, southeast of Huaying City and west of the study area, along with Xiangyu Railway. Geographical environment and vegetation features were found to significantly explain 67.4 % and 32.6 % of the total effects in shallow landslides susceptibility, respectively. Specifically, the spatial distribution of shallow landslides susceptibility were primarily influenced by geological engineering rock group, distance to faults、stand types and distance to river. Geographical environment factors could indirectly affect changes in vegetation features, thereby indirectly affecting the spatial distribution of shallow landslides susceptibility. Findings from this research could be helpful for scientific decision-making and technical assistance for early warning, prevention, and control of rainstorm-induced landslides in highly vegetation covered areas.

Geo-electrical investigation for groundwater reserves in the Boranakanive Reservoir Catchment in Tumkur district, Karnataka, India

The groundwater resources have been under significant constraints due to excessive exploitation and climate change. It is imperative to comprehend these dwindling resources' characteristics, given their distribution and occurrence variability across the space and time. A semi-arid climate characterizes the study area and agriculture is the primary occupation, their reliance on groundwater is indispensable due to the lack of surface water sources and erratic rainfall patterns. Consequently, the study employed the Schlumberger array of 200 m-spaced half-current electrodes Vertical Electrical Sounding (VES) survey was conducted at 100 VES locations to identify groundwater potential zones. Further, curve-matching and correlation of lithologies have been carried out from various VES-soundings, and also generated pseudo-cross sections of the subsurface geometry. The results revealed the existence of five geoelectrical resistivity layers as follows layer 1–6 to 422 Ωm, layer 2–8 to 7708 Ωm, layer 3–4 to 37117 Ωm, layer 4–37 to 95059 Ωm, and layer 5–205 to 83142 Ωm. The iso-apparent resistivity maps of the study area reveal values ranging for the first layer 11Ωm - 333 Ωm, the second layer 23Ωm - 5347Ωm, the third layer 11Ωm - 26734Ωm and 10Ωm - 67250Ωm for the fourth layer. The present research determined that the third and fourth layer constitute the principal aquifers due to their fractured structures. As a result, these layers produce a significant quantity of groundwater in the north-eastern (NE) and southern (S) regions of the study region. As a consequence of these findings, further exploration and management of groundwater resources in the study areas can be carried out with valuable insight.

A multivariate statistical framework for mixed storm types in compound flood analysis

Abstract. In coastal regions, compound flooding can arise from a combination of different drivers, such as storm surges, high tides, excess river discharge, and rainfall. Compound flood potential is often assessed by quantifying the dependence and joint probabilities of flood drivers using multivariate models. However, most of these studies assume that all extreme events originate from a single population. This assumption may not be valid for regions where flooding can arise from different generation processes, e.g., tropical cyclones (TCs) and extratropical cyclones (ETCs). Here we present a flexible copula-based statistical framework to assess compound flood potential from multiple flood drivers while explicitly accounting for different storm types. The proposed framework is applied to Gloucester City, New Jersey, and St. Petersburg, Florida, as case studies. Our results highlight the importance of characterizing the contributions from TCs and non-TCs separately to avoid potential underestimation of the compound flood potential. In both study regions, TCs modulate the tails of the joint distributions (events with higher return periods), while non-TC events have a strong effect on events with low to moderate joint return periods. We show that relying solely on TCs may be inadequate when estimating compound flood risk in coastal catchments that are also exposed to other storm types. We also assess the impact of non-classified storms that are not linked to either TCs or ETCs in the region (such as locally generated convective rainfall events and remotely forced storm surges). The presented study utilizes historical data and analyzes two populations, but the framework is flexible and can be extended to account for additional storm types (e.g., storms with certain tracks or other characteristics) or can be used with model output data including hindcasts or future projections.

Exploring hydrological system performance for alpine low flows in local and continental prediction systems

Study region: The European alpine space.Study focus: Despite the advancements in hydrological modeling, there is a lack of comparative studies quantifying the performance differences between local and large-scale models, particularly in the context of drought and low flow assessment. This study addresses this gap by designing a framework to evaluate the European Flood Awareness System (EFAS), a continental system, in simulating low flow events across 101 alpine stations from 1999–2018, with detailed comparisons to two local systems — GR6J in France and PREVAH in Switzerland — at 34 of these stations.New hydrological insights for the region: The results show that the local systems, PREVAH and GR6J, generally outperform the continental system EFAS for almost all stations. The performance gap between the systems increases as low flow conditions intensify, highlighting the importance of local systems for extreme low flow events. Despite EFAS not being specifically set up for low flows, it has shown an overall acceptable performance compared to the local hydrological systems, especially at locations that are not calibrated within the EFAS system, indicating its potential in ungauged areas. This study lays a foundation for understanding how a continental hydrological system like EFAS can complement local systems or fill the gap when a local system is unavailable to provide reliable predictions of low flow conditions.

Apatite as an indicator of tectono-magmatic evolution of silica-undersaturated to silica-oversaturated rocks on the NW Indian Plate margin

Permo-Carboniferous intrusive rocks situated on the NW boundary of the Indian Plate between the Main Mantle Thrust (MMT) and Main Boundary Thrust (MBT) have tremendous potential for enhancing our knowledge of regional tectono-magmatic activity in Pakistan, yet these units have received only limited investigation to date. Here, we examine the petrology, apatite geochemistry and Sr-Nd isotopes, and geochronology of the silica-undersaturated (sodalite syenite and nepheline syenite), silica-saturated (monzonite and quartz syenite), and silica-oversaturated (granite and quartz monzonite) intrusive suites of the Ambela Granitic Complex (AGC) in northern Pakistan. Cathodoluminescent (CL) images of apatite in the three suites show mostly oscillatory zonation and a homogenous texture. The apatite chemistry of three intrusives is characterized by high fluorine (F), rare earth element (REE), yttrium (Y), and thorium (Th) contents, and low levels of chlorine (Cl), iron oxide (FeO) and magnesium oxide (MgO), suggesting a magmatic origin. The three suites exhibit variation in Sr-Nd isotopes, i.e., 87Sr/Sr86i = 0.7035 to 0.7057 and εNd(t) = +0.3 to +6.0 for the silica-undersaturated group, 87Sr/Sr86i = 0.7044 to 0.7205 and εNd(t) = +1.8 to +3.8 for the silica-saturated group, and 87Sr/Sr86i = 0.7075 to 0.7186 and εNd(t) = −2.5 to +1.2 for the silica-oversaturated group. Garnet stability field indicators in the nepheline syenite imply a deeply sourced magma, with Sr-Nd isotopic, and trace-element compositions of the apatite indicating formation in the subcontinental lithospheric mantle. In contrast, the silica-oversaturated melts formed during magma ascent through crustal interactions at a range of depths, with their apatites showing affinity with A-type granites. Apatite grains from the three magmatic groups show distinctive Sr, Eu and Y patterns, reflecting less fractionation of the silica-undersaturated and -saturated suites than of the silica-oversaturated suite. Furthermore, apatites of the former suites have higher Eu/Eu* and SO3 and lower Ce/Ce* than those of the latter suite, suggesting development under more oxidizing magmatic conditions. TDM2 ages demonstrate parent material of Mesoproterozoic to Neoproterozoic age, whereas LA-ICP-MS U-Pb dating of magmatic apatite indicates cooling of all suites concurrently at ∼322–262 Ma. The latter ages document significant magmatic activity in the study region during the Late Carboniferous to Middle Permian, probably in connection with rifting of the northern margin of the supercontinent Gondwana, leading to opening of the Neo-Tethys Ocean.

Identification of Anthropogenic Impact and Indicators of Landscape Transformation in the Fatala River Basin (Republic of Guinea)

The aim of this study is to identify the main factors of anthropogenic impact and indicators of landscape transformation in the Fatala River Basin in the Republic of Guinea. Our fieldwork in the Boke and Kindia regions was the main source of materials and data. The landscape and ecological situation of nine key study plots were characterized. These key plots make up a representative series of transformed and natural landscapes. We complemented our fieldwork with Landsat satellite image analysis. We learned that the main factors of anthropogenic impact in the Fatala River Basin are the systematic burning of vegetation, mechanical disturbances of soil and vegetation cover, the depletion of fertile topsoil, grazing, and the littering of the landscape with household waste. The indicators of landscape transformation are deforestation, changes in the natural vegetation cover, and mechanically disturbed lands. We identified five main stages of agro-landscape development, starting from the clearing of a plot by burning vegetation (stage I) and ending with the completion of the agricultural activity in the plot and its abandonment to restore the topsoil (stage V). The limiting factors of nature management are elevation differences, the rapid restoration of vegetation cover, and rocky/gravelly substrate. It is possible to identify transformed landscapes in large or hard-to-reach regions using satellite images. Thus, natural or quasi-natural landscapes can be identified based on the lower surface temperature relative to the surrounding lands. The normalized difference vegetation index (NDVI) and normalized difference moisture index (NDMI) could be useful for identifying agricultural pasture plots within a tropical forest using long-term satellite data series. We revealed a tendency for landscape deterioration in the middle and upper parts of the Fatala River Basin, while vegetation cover is being restored in the lower part of the basin. Finally, we propose some measures to rehabilitate transformed landscapes and increase the efficiency of agricultural production in the study region.

Effect of complex orography on numerical simulations of a downburst event in Spain

A downburst is a localized and intense downdraft of air that descends quickly from the middle troposphere and reaches the Earth's surface. It is frequently originated by a thunderstorm or a supercell. Downburst winds can cause significant damage to buildings, infrastructure, and pose a great threat to aviation traffic. On July 1, 2018, many supercells were spotted near the Zaragoza Airport (Spain), and at least one of them generated a downburst that affected the airport, causing significant damage in the surrounding area. This event is here simulated using the Weather Research and Forecasting (WRF-ARW) numerical weather prediction model. Three different WRF-ARW orography experiments are carried out to investigate if the region's complex orography has an important role in supercell and downburst development over the research area. One of the three experiments uses the default orography as control; another one uses a 90 % smoothed orography, and the third experiment is configured with a high-resolution dataset. Several atmospheric and convective variables are compared for each orography experiment. Results show that MUCAPE is clearly higher when the orography complexity is reduced. The smoothing process leads to a more uniform wind flow, contributing to the formation of numerous supercells. However, supercells channel through valleys and mountains in the control and high-resolution orography experiments, where the surface wind divergences are uniquely reproduced, and the highest reflectivity values are observed. Moisture advection from the Mediterranean Sea is essential in the process, reaching more deeply into the study region in the smoothed orography experiment due to the lack of orographic barriers. Orography affects dynamic and thermodynamic features, which have considerable effects on the formation and development of downbursts.

Association of serum uromodulin with diabetic kidney disease: a systematic review and meta-analysis

BackgroundSeveral studies have investigated the association between the changes of serum uromodulin and diabetic kidney disease (DKD). However, the results are still controversial. Therefore, this meta-analysis was conducted to provide a comprehensive evaluation of the association between serum uromodulin levels and DKD.MethodsPubMed, Cochrane library, Web of Science, and Scopus were systemically searched following the PRISMA protocol to identify the studies that reported the relationship between serum uromodulin level and DKD. To investigate the association between uromodulin and DKD, a standardized mean difference (SMD) with a 95% confidence interval (CI) was used. When significant heterogeneity was detected (I2 > 50%), sensitivity and subgroup analyses were performed to determine the source of heterogeneity. The quality assessment was determined using the Newcastle-Ottawa scale (NOS), and the publications bias were determined by the funnel plot and Egger’s test.ResultsIn total, 6 studies with 1774 patients were included in the final analysis. The random effect model was used. The pooled results showed that the serum uromodulin levels were significantly decreased in patients with DKD (SMD: -0.31; 95% CI: -0.48 to -0.13) (I2 = 45%). Upon applying the sensitivity analysis, it showed (SMD: -0.38; 95% CI: -0.49 to -0.27) (I2 = 3%). Subgroup analysis showed that uromodulin level was significantly decreased in DKD regardless of the region of study, in America (SMD: -0.34; 95% CI: -0.51 to -0.17; p < 0.0001), Europe (SMD: -0.54; 95% CI: -1.06 to -0.02; p = 0.04), and Asia (SMD: -0.63; 95% CI: -1.15 to -0.11; p = 0.02), with stronger predictive value in America and Asia than in Europe. Additionally, uromodulin levels were significantly decreased in both type 1 (SMD: -0.34; 95% CI: -0.51 to -0.17; p < 0.0001) and type 2 diabetes (SMD: -0.58; 95% CI: -0.95 to -0.22; p = 0.002).ConclusionThis meta-analysis showed a significant association between low levels of serum uromodulin and DKD. So, it could have a predictive role for DKD. However, its performance varied across subgroup analyses restricted by race and clinical settings. Moreover, further studies are required with a focus on the cut-off value for predicting diagnostic accuracy.

Vertical electrical sounding technique for evaluating and characterizing weathered Neogene basaltic aquifer in Jbab area, Southern Syria

ABSTRACT Vertical electrical sounding (VES) technique with Schlumberger array is used to characterize the subsurface basaltic aquifers in Jbab area, Southern Syria. The Dar-Zarrouk (D-Z) parameters of 18 VES points allow to characterize the subsurface basaltic environment and the weathered Neogene basalt aquifer in the study region. The Neogene basaltic aquifer exists at a depth varying between 12.40 and 291.8 m, its thickness varies between 32.3 and 244.4 m. Its resistivity is between 12.53 and 53.40 Ω.m. The hydraulic conductivity (K) varies between 0.64 and 0.68 m/day, while the transmissivity (T) ranges between 21.94 and 162.68 m2/day. The overburden protective capacity (OPC) is evaluated through modeling the longitudinal conductance of the layers above the Neogene basaltic aquifer. OPC varies between 0.064 Ω-1 and 2.90 Ω-1, reflecting that more than 83% of the study region is identified by relatively moderate to good aquifer protective capacity. The use of the VES technology with its related D-Z parameters provides a vital information about the subsurface weathered basaltic aquifer in the study area, and can be practiced worldwide to characterize areas with similar geological context.

Characteristics of Urban–Rural Integration at the County-Scale Interface: The Case of Linqu County, China

Urban–rural integration (URI) has emerged as a crucial strategy to bridge urban and rural disparities and promote more sustained urbanisation paradigms in China and abroad. The urban–rural interface, where urban and rural spaces and daily activities are closely intertwined, reflects the complex and evolving dynamics of this integration, serves as a focal point for studying URI, and requires unique considerations in spatial planning. This study focuses on the scale of the county level and the basic spatial units for spatial planning practice in China to examine different types of urban–rural interfaces and their URI dynamics at a county level. By taking Linqu County as a case study region, land use data from Landsat remote sensing datasets were collected every 5 years from 2000 to 2020 to support the analysis of changes in the urban–rural interface. Three dimensions of land mixed-use features were employed, including the area and density, edge and shape, and aggregation and dispersion of the construction land in the region. When combined with the proportion of rural land use, the urban–rural interfaces were identified using the entropy method. This study then employed spatial analysis, the standard deviation ellipse method, and spatial autocorrelation to recognise URI dynamics, and three driving forces were identified and further analysed to support suggestions for county-level spatial planning. This research empirically enriches the understanding of the urban–rural interfaces and URI dynamics of Linqu, China. The methods and suggestions derived from the empirical study can offer potential solutions to promote URI in China and enhance urban–rural linkage in the global context to reach more sustained development.

Spatial distribution pattern of soil organic matter in the wind erosion region of northeastern China based on the cokriging method

Soil wind erosion triggers complex particle migration from the source to downwind regions. During this process, soil organic matter (SOM), primarily adsorbed onto particle surfaces, exhibits distinct spatial differentiation across affected areas. Knowledge about the spatial distribution of SOM and its impact factors in wind erosion regions is essential for a deep understanding of global carbon cycling. In the wind erosion region of northeastern China, a crucial base for livestock and commercial grain production, profound changes in land quality driven by climate change and human activities have intricately altered SOM spatial patterns. However, detailed studies on the spatial variability of surface SOM in this region remain scarce. A total of 374 surface soil samples from this region were analyzed for SOM and soil pH. Combined with spatial data sets including particle-size distribution, soil moisture (SM), air temperature (T), and the normalized difference vegetation index (NDVI), the regional spatial distribution patterns of SOM were revealed and mapped using the ordinary kriging (OK) and cokriging (CK) approaches. The results indicated strong variations of SOM in space, with corresponding coefficients of variation exceeding 35 % across the entire region and each land use. According to the semivariogram analysis, SOM demonstrates moderate spatial dependency in the study region, exhibiting spatially positive correlations with clay content (CLAY), SM, and NDVI, and negative correlations with pH, soil sand content (SAND), and T. Among the various impact factors, incorporating SAND as an auxiliary variable in CK interpolation achieved the greatest improvement in the accuracy of SOM spatial distribution simulation compared to the OK model, increasing the explained variance from 35 % to 75 %. This simulation showed a general downward trend of SOM from the northeast to the southwest of the study region, with 65.24 % of the area displaying SOM ranging from 10-30 g·kg−1. The values of SOM greater than 30 g·kg−1, comprising 19.43 % of the total region, were primarily located in the humid and semi-humid meadow steppes and forests. In contrast, areas with SOM below 10 g·kg−1 accounted for only 15.33 %, mainly situated in the arid desert steppe and the Horqin sandy lands. These findings provide a scientific basis for understanding regional SOM loss and developing efficient measures for sand prevention and control.