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Tidal creeks play a critical role in delivering water, suspended sediments, and nutrients to coastal wetlands, so it is important to understand the characteristics of the tidal creek system to guide the development and sustainable utilization of coastal wetlands. Using the coastal wetlands of the Liao River Estuary (LRE) as a study area, this study accurately divided the tidal flat based on the principle of tidal correction, extracted the linear features of tidal creeks using high-resolution remote sensing (RS) data, and then classified the tidal creeks on a tidal flat using the tidal creek ordering algorithm. Our study aimed to quantify the morphological characteristics of tidal creeks and qualitatively evaluate the parameters of the tidal creek network in the study area. The study results show obvious spatial heterogeneity in the order and the average length of tidal creeks in the coastal wetlands of the LRE. With the increase in the order of tidal creeks, the average length of tidal creeks increased exponentially and the number of tidal creeks decreased exponentially in the study area. The total density of tidal creeks was related to the beach surface elevation gradient, and the density and frequency of tidal creeks reduced substantially with an increase in the order of tidal creeks. The sinuosity ratio of tidal creeks declined sharply with a fall in the beach surface elevation gradient. The average bifurcation ratio of tidal creeks in the upper intertidal zone was higher than that in other zones, indicating that the tidal creeks in the upper intertidal zone were erratic. In addition, the hydrological connectivity of the tidal creek network in the upper intertidal zone and the development of the tidal creek system in the supratidal zone were the highest in the LRE. The study results help understand the spatial variations in tidal creek morphology under the influence of tidal hydrodynamics. [ABSTRACT FROM AUTHOR]

Over the last decades, concern has arisen worldwide about the negative impacts of pesticides on the environment and human health. Exposure via dust ingestion is important for many chemicals but poorly characterized for pesticides, particularly in Africa. We investigated the spatial and temporal variations of 30 pesticides in dust and estimated the human exposure via dust ingestion, which was compared to inhalation and soil ingestion. Indoor dust samples were collected from thirty-eight households and two schools located in two agricultural regions in South Africa and were analyzed using high-performance liquid chromatography coupled to tandem mass spectrometry. We found 10 pesticides in dust, with chlorpyrifos, terbuthylazine, carbaryl, diazinon, carbendazim, and tebuconazole quantified in >50% of the samples. Over seven days, no significant temporal variations in the dust levels of individual pesticides were found. Significant spatial variations were observed for some pesticides, highlighting the importance of proximity to agricultural fields or of indoor pesticide use. For five out of the nineteen pesticides quantified in dust, air, or soil (i.e., carbendazim, chlorpyrifos, diazinon, diuron and propiconazole), human intake via dust ingestion was important (>10%) compared to inhalation or soil ingestion. Dust ingestion should therefore be considered in future human exposure assessment to pesticides. [ABSTRACT FROM AUTHOR]

Water is one of the most basic entities, especially in semiarid regions where low precipitation and limited surface water resources bring more emphasis on the use of groundwater leading to endangering and overexploitation. Therefore, quantity with monitoring of groundwater quality at regular intervals becomes of utmost importance for understanding its suitability for drinking and irrigation. This study aims in understanding spatial variations and their trend in terms of quality over a decade (2010–2020) using different hydrochemical parameters in the vicinity of the coastal tracts of the Mundra block. Samples were analyzed for TDS, pH, EC, TH, major cations, and anions. Drinking suitability was identified by correlating parameters with WHO, BIS standards and by preparing WQI maps. Irrigational suitability was found by SAR, RSC, KI, Na %, MH, and PI. Reduced water level (RWL) values represented a further increase in the reversal flow of groundwater in a decade leading to an increment in salinity and seawater intrusion. The study area in most of the analysis is possessing much higher values above safer limits when compared to 2010 and 2020, making the water very much unacceptable for drinking and irrigation. The major cause in the area is overexploitation and unconditional deeper drilling, resulting in an increase in coastal salinity and seawater intrusion. The use of such water tends to harm agriculture, soil condition as well as human health. [ABSTRACT FROM AUTHOR]

Farmland crop residue burning (FCRB) significantly impacts air quality, necessitating understanding its spatiotemporal variations to evaluate control measures and guide future policies. This study analyzes FCRB across China from 2013 to 2022 using remote sensing technology and spatiotemporal analysis. Results indicate that the first phase (2013-2017) of the "Clean Air Action" control measures has been proven ineffective, with a 30.9 % increase in FCRB. Effective measures implemented in the second phase (2018-2020) resulted in a reduction of 41.4 % and led to a decrease of 34.3 % in 2022 compared to 2013. FCRB exhibits significant seasonal and regional variations, with a 69 % decrease in autumn and a 23 % increase in spring. While the variations in FCRB across regions are found to be significantly negatively correlated with the stringency of control measures, there is a 61.2 % reduction in the central region, 42.4 % in the western region, 29.7 % in the eastern region with the highest intra-regional disparities, and only 4.5 % in the northeastern region, which is attributed to the high FCRB in Heilongjiang province. FCRB demonstrates the "club convergence" phenomenon and the spillover effects of adjacent provinces, leading to high-high clusters in the northeastern region, emphasizing the need for region-specific control measures (e.g., Heilongjiang province in the northeastern) and the implementation of similar control measures in adjacent areas. Additionally, it is necessary to avoid the rebound phenomenon determined by the analysis of the kernel density estimation curve. Our findings underscore the importance of tailored strategies in managing FCRB and improving air quality in critical areas., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Twenty‐two sites, subjected to an IZZI‐modified Thellier‐Thellier experiment and strict selection criteria, recover a paleomagnetic axial dipole moment (PADM) of 62.2 ± 30.6 ZAm2 in Northern Israel over the Pleistocene (0.012–2.58 Ma). Pleistocene data from comparable studies from Antarctica, Iceland, and Hawaii, re‐analyzed using the same criteria and age range, show that the Northern Israeli data are on average slightly higher than those from Iceland (PADM = 53.8 ± 23 ZAm2, n = 51 sites) and even higher than the Antarctica average (PADM = 40.3 ± 17.3 ZAm2, n = 42 sites). Also, the data from the Hawaiian drill core, HSDP2, spanning the last half million years (PADM = 76.7 ± 21.3 ZAm2, n = 59 sites) are higher than those from Northern Israel. These results, when compared to Pleistocene results filtered from the PINT database (www.pintdb.org) suggest that data from the Northern hemisphere mid‐latitudes are on average higher than those from the southern hemisphere and than those from latitudes higher than 60°N. The weaker intensities found at high (northern and southern) latitudes therefore, cannot be attributed to inadequate spatiotemporal sampling of a time‐varying dipole moment or low quality data. The high fields in mid‐latitude northern hemisphere could result from long‐lived non‐axial dipole terms in the geomagnetic field with episodes of high field intensities occurring at different times in different longitudes. This hypothesis is supported by an asymmetry predicted from the Holocene, 100 kyr, and 5 million year time‐averaged geomagnetic field models. Plain Language Summary: According to the Geocentric Axial Dipole hypothesis, the geomagnetic field may be approximated by a dipole that is aligned with the spin axis and positioned in the center of Earth. Such a field would produce field strengths that vary with respect to latitude with high latitudes associated with high intensities, or, converted to equivalent "virtual" dipole moments, would be essentially independent of latitude. It has long been suggested that high latitudes have had lower field strengths than predicted by such a model, when compared to data from mid‐latitudes, but these claims have always been accompanied by caveats regarding differences in temporal coverage or methodological approaches. Here, we present new data from Pleistocene aged rapidly cooled cinder cones and lava flow tops from Israel. We compare these data to other recent data sets obtained from rapidly cooled materials collected in Hawaii, Iceland, and Antarctica. These confirm that virtual dipole moments from mid northern hemisphere latitudes are higher than those from high latitudes and from the southern hemisphere. Global compilations spanning the Pleistocene, when filtered for quality also shows this behavior as do time averaged field models. Therefore, field strengths over even millions of years can have persistent non‐dipole field contributions. Key Points: We present 26 40Ar/39Ar ages from volcanic rocks from Northern Israel (90 ka to 3.3 Ma)Twenty‐two Pleistocene intensity estimates have a mean paleomagnetic dipole moment of 62.2 ± 30.6 ZAm2The northern hemisphere had persistently higher fields than the southern during the Pleistocene [ABSTRACT FROM AUTHOR]

Leaf N and P stoichiometry in terrestrial ecosystems has been widely investigated in recent years owing to the importance of these elements in improving the predicted vegetation responses to global changes. The vertical distribution of leaf N and P stoichiometry has attracted increasing attention because of the dramatic changes in environmental factors at regional scales. However, the characteristics of leaf N and P stoichiometry in the southeast Qinghai-Tibet plateau (SET) are not clear, although this area is sensitive to global change. Here, we analyzed the leaf N and P concentrations in dominant plant species on natural altitudinal gradients on the Duoxiongla (DXL), Sejila (SJL), Mila (ML), and Gangbala (GBL) mountains across the SET all the way to central Tibet. Our results showed that the leaf N concentrations were comparable among the regions, whereas the leaf P concentrations dramatically decreased from SET to central Tibet (CT). The leaf N concentrations were 23.6, 21.3, 20.8, and 22.4 g kg−1, and the leaf P concentrations were 2.40, 2.49, 1.94, and 1.59 g kg−1 on the SJL, DXL, ML and GBL mountains, respectively. The leaf N/P ratios on the DXL, SJL, ML, and GBL mountains were 8.81, 10.3, 11.2, and 14.2, respectively. Considering the increasing trend of the leaf N/P ratio from southeast Qinghai-Tibet plateau to central Tibet, N limitation might widely exist in well vegetated ecosystems in the Qinghai-Tibet plateau. [ABSTRACT FROM AUTHOR]

The Weihe River Basin (WRB), the largest tributary of the Yellow River Basin (YRB), is located in the northwest of China. As the "mother river" of the Guanzhong Plain, it plays an important role in the development of Guanzhong City Group. Based on pH, electric conductivity (EC), total dissolved solids (TDS), and major ionic concentrations of 227 samples collected from the main stream (MS), northern tributaries (NT), and southern tributaries (ST) of the WRB, we explored spatial differential characteristics of hydrochemistry and their controlling factors, solute sources, and water quality of surface water. The results revealed mildly alkaline pH and much higher TDS values than the global average with mean values of 7.9 and 1037.7 mg L−1, respectively. Except NO3−, the concentrations of major ions in the MS and NT were higher than those of the ST, with similar spatial distribution patterns of Ca2+, Na+, Mg2+, SO42−, and Cl−. Na+ and SO42− were the most dominant cation and anion in the MS and NT controlled by both rock weathering and evaporation-crystallization processes. Ca2+ and HCO3− were the most dominant cation and anion in the ST mainly controlled by rock weathering process. Evaporite dissolution contributed the most to dissolved solutes in the MS and NT, while carbonate weathering dominated dissolved solutes in the ST. These findings were confirmed by the results of correlation matrix, principal component analysis (PCA), stoichiometric plots, and different water types identified as Na-SO4·Cl in the MS and NT, and Ca-HCO3 in the ST. Atmospheric and anthropogenic inputs had a minor effect on the surface water chemistry. However, human activities could not be ignored in the ST accounting for 10.9% of the total dissolved solutes, mainly because of the fertilizer application. And the surface water of the ST was more suitable for irrigation and drinking purposes than that of the MS and NT. Knowledge of our findings could contribute new insights to the solute geochemistry and sustainable management of water resources in the lithologically distinct segments of the WRB and other similar areas. [ABSTRACT FROM AUTHOR]

Background: Accessibility and utilization of postnatal newborn check-ups within 2 days after delivery are critical for a child's survival, growth, and development. However, the service delivery is not yet improved and fluctuates across the geographical locations in Ethiopia. Therefore, this study aimed to assess the spatial distribution and determinants of newborns not received postnatal check-ups within 2 days after birth in Ethiopia.Methods: A secondary data analysis of the Ethiopia Demographic and Health Survey (EDHS) 2016 was done among live births within 2 years preceding the survey. A multilevel binary logistic regression model was fitted to identify the factors associated with the outcome variable. Adjusted Odds Ratio with 95% (Confidence Interval) was calculated and used as a measure of associations and variables with a p-value < 0.05, were declared as statistically significant.Results: A total of 4036 live newborns in Ethiopia were included in the analysis, of whom half (51.21%) were females. The mean age of the mothers was 33+ SD 1.3, and more than 60 % (61.56%) of the mothers were not educated. The national prevalence of newborns not receiving postnatal check-ups within 2 days after birth was 84.29 (95% CI: 83.10-85.41) with significant spatial variations across the study area. Mothers who had no ANC visits were 58% higher than (AOR = 0.42(0.27-0.66) mothers who had > 4 ANC visits. Mothers who gave birth at home and others were 80% (AOR = 0.02(0.01-0.29) and 25% (AOR = 0.76(0.59-0.99), higher than mothers delivered at hospital. Rural mothers were 1.90 times higher (AOR = 1.90(1.29-2.81) than urban mothers, and mothers live in administrative regions of Afar 66% (AOR = 0.34(0.16-0.69), Oromia 47% (AOR = 0.53(0.30-0.91), Somali 60% (AOR = 0.40 (0.22-0.74),Benishangul 50% (AOR = 0.50 (0.27-0.92), SNNPR 67% (AOR = 0.33(0.19-0.57), Gambela 70% (AOR = 0.30 (0.16-0.56), Harari 56% (AOR = 0.44 (0.25-0.78), and Dire Dawa70% (AOR = 0.30 (0.17-0.54) were higher than Addis Abeba for not receiving postnatal checkup of new born within the first 2 days, respectively.Conclusions: Low postnatal check-up utilization remains a big challenge in Ethiopia, with significant spatial variations across regional and local levels. Spatial clustering of not receiving postanal check-ups within 2 days was observed in Afar, Oromia, Gambela, Benishangul, SNNPR, Harari, and Dire Dawa regions. Residence, ANC visits, place of delivery, and administrative regions were significantly associated with not receiving postnatal check-ups. Geographically targeted interventions to improve ANC follow-up and institutional delivery should be strengthened. [ABSTRACT FROM AUTHOR]

The United Nations Sustainable Development Goals (SDGs) include 17 interlinked goals designed to be a blueprint for the world's nations to achieve a better and more sustainable future, and the specific SDG 3 is a public health–related goal to ensure healthy living and promote well-being for all population groups. To facilitate SDG planning, implementation, and progress monitoring, many SDG indicators have been developed. Based on the United Nations General Assembly resolutions, SDG indicators need to be disaggregated by geographic locations and thematic environmental and socioeconomic characteristics for achieving the most accurate planning and progress assessment. High-resolution data such as those captured at the village level can provide comparatively more precise insights into the different socioeconomic and environmental factors relevant to SDGs, therefore enabling more effective sustainable development decision-making. Using India as our study area and the child malnutrition indicators stunting, underweight, and wasting as examples of public health–related SDG indicators, we have demonstrated a process to effectively derive environmental variables at the village level from satellite big datasets on a cloud platform for SDG research and applications. Spatial analysis of environmental variables regarding vegetation, climate, and terrain have shown spatial grouping patterns across the entire study area, with each village group having different statistics. Correlation analysis between these environmental variables and stunting, underweight, and wasting indicators show a meaningful relationship between these indicators and vegetation index, land surface temperature, rainfall, elevation, and slope. Identifying the spatial variation patterns of environmental variables at the village level and their correlations with child malnutrition indicators can be an invaluable tool to facilitate a clearer understanding of the causes of child malnutrition and to improve area-specific SDG 3 implementation planning. This analysis can also provide meaningful support in assessing and monitoring SDG implementation progress at the village level by spatially predicting SDG indicators using available socioeconomic and environmental independent variables. The methodology used in this study has the potential to be applied to other similar regions, especially low-to-middle income countries where a high number of children are severely affected by malnutrition, as well as to other environmentally related SDGs, such as Goal 1 (No Poverty) and Goal 2 (Zero Hunger). [ABSTRACT FROM AUTHOR]

Earthquake source parameters, such as slip on the planes of finite faults, have spatially variable distributions, and seismic ground motions significantly fluctuate in accordance with the characteristics of complexity. The complexity of fault parameters should thus be evaluated properly. Although self-similar models consider the complexity of the fault parameters, they have not been exhaustively used to validate earthquakes that occur in Japan. In this study, for multiple earthquakes in Japan, the slip complexities of finite faults are evaluated using the self-similar model. Slip spectra are fitted using the von Karman autocorrelation function; furthermore, the Hurst exponents and correlation lengths are compared with previous studies dealing with earthquakes around the world. Differences between source types are also examined. The Hurst exponents H are unaffected by magnitude, and the difference between the source types is small. The median value of H is 0.77, which is nearly the same as the global average value indicated by Mai and Beroza (2002). The correlation lengths along-strike ax have positive correlations with magnitude; furthermore, no differences were observed between source types. The ax characteristics are nearly the same as the global average value; however, the correlation lengths down-dip ay correlates positively with magnitude. Nevertheless, there are differences for each source type. The ay characteristics have saturating trends for each source type, which is attributed to the thickness of the seismogenic layer. The moment magnitude Mw saturates at 6.3 and 8.4 for crustal and interplate earthquakes, respectively. This Mw is nearly consistent with the boundary between the first and second stages of three-stage scaling. [ABSTRACT FROM AUTHOR]

Heat stroke is a serious heat‐related health outcome that can eventually lead to death. Due to the poor accessibility of heat stroke data, the large‐scale relationship between heat stroke and meteorological factors is still unclear. This work aims to clarify the potential relationship between meteorological variables and heat stroke, and quantify the meteorological threshold that affected the severity of heat stroke. We collected daily heat stroke search index (HSSI) and meteorological data for the period 2013–2020 in 333 Chinese cities to analyze the relationship between meteorological variables and HSSI using correlation analysis and Random forest (RF) model. Temperature and relative humidity (RH) accounted for 62% and 9% of the changes of HSSI, respectively. In China, cases of heat stroke may start to occur when temperature exceeds 36°C and RH exceeds 58%. This threshold was 34.5°C and 79% in the north of China, and 36°C and 48% in the south of China. Compared to RH, the threshold of temperature showed a more evident difference affected by altitude and distance from the ocean, which was 35.5°C in inland cities and 36.5°C in coastal cities; 35.5°C in high‐altitude cities and 36°C in low‐altitude cities. Our findings provide a possible way to analyze the interaction effect of meteorological variables on heat‐related illnesses, and emphasizes the effects of geographical environment. The meteorological threshold quantified in this research can also support policymaker to establish a better meteorological warning system for public health. Plain Language Summary: The impact of extreme heat events on population has become of urgent public health concern. In China, the real mortality and morbidity data are not publicly available and data of some diseases are not enough recorded. Thus, it is difficult to build a solid relationship between heat strokes and meteorological variables in large spatial scale. Internet search data, highly correlated with real heat stoke cases, was adopted as a new data set in our research instead of the heat‐related morbidity data to investigate the relationship between heat strokes and multiple meteorological variables. According to Random forest model, temperature and relative humidity (RH) were identified as the most important factor, which mainly affected the severity of heat strokes. We quantified the meteorological threshold that affected the severity of heat strokes as well. Heat strokes may start to occur when temperature exceeds 36°C and RH exceeds 58% in China. The temperature of this threshold is higher in the south or low‐latitude region or coastal region of China. This work provides new insights for health research and help to timely alert the public in adverse weather conditions. Key Points: Internet search data could help to evaluate the health impact in large scale to address the data shortageIncreasing temperature and relative humidity (RH) led to sharply increased heat stroke, particularly when maximum temperature exceeds 36°C and RH exceeds 58%Meteorological threshold was affected by geographical factors like altitude, latitude and distance from ocean [ABSTRACT FROM AUTHOR]

Abstract Twenty‐two sites, subjected to an IZZI‐modified Thellier‐Thellier experiment and strict selection criteria, recover a paleomagnetic axial dipole moment (PADM) of 62.2 ± 30.6 ZAm2 in Northern Israel over the Pleistocene (0.012–2.58 Ma). Pleistocene data from comparable studies from Antarctica, Iceland, and Hawaii, re‐analyzed using the same criteria and age range, show that the Northern Israeli data are on average slightly higher than those from Iceland (PADM = 53.8 ± 23 ZAm2, n = 51 sites) and even higher than the Antarctica average (PADM = 40.3 ± 17.3 ZAm2, n = 42 sites). Also, the data from the Hawaiian drill core, HSDP2, spanning the last half million years (PADM = 76.7 ± 21.3 ZAm2, n = 59 sites) are higher than those from Northern Israel. These results, when compared to Pleistocene results filtered from the PINT database (www.pintdb.org) suggest that data from the Northern hemisphere mid‐latitudes are on average higher than those from the southern hemisphere and than those from latitudes higher than 60°N. The weaker intensities found at high (northern and southern) latitudes therefore, cannot be attributed to inadequate spatiotemporal sampling of a time‐varying dipole moment or low quality data. The high fields in mid‐latitude northern hemisphere could result from long‐lived non‐axial dipole terms in the geomagnetic field with episodes of high field intensities occurring at different times in different longitudes. This hypothesis is supported by an asymmetry predicted from the Holocene, 100 kyr, and 5 million year time‐averaged geomagnetic field models.

Abstract Heat stroke is a serious heat‐related health outcome that can eventually lead to death. Due to the poor accessibility of heat stroke data, the large‐scale relationship between heat stroke and meteorological factors is still unclear. This work aims to clarify the potential relationship between meteorological variables and heat stroke, and quantify the meteorological threshold that affected the severity of heat stroke. We collected daily heat stroke search index (HSSI) and meteorological data for the period 2013–2020 in 333 Chinese cities to analyze the relationship between meteorological variables and HSSI using correlation analysis and Random forest (RF) model. Temperature and relative humidity (RH) accounted for 62% and 9% of the changes of HSSI, respectively. In China, cases of heat stroke may start to occur when temperature exceeds 36°C and RH exceeds 58%. This threshold was 34.5°C and 79% in the north of China, and 36°C and 48% in the south of China. Compared to RH, the threshold of temperature showed a more evident difference affected by altitude and distance from the ocean, which was 35.5°C in inland cities and 36.5°C in coastal cities; 35.5°C in high‐altitude cities and 36°C in low‐altitude cities. Our findings provide a possible way to analyze the interaction effect of meteorological variables on heat‐related illnesses, and emphasizes the effects of geographical environment. The meteorological threshold quantified in this research can also support policymaker to establish a better meteorological warning system for public health.

Chlorinated paraffins (CPs), a class of complex mixtures synthesized from polychlorinated n-alkanes, are widely used as flame retardants, plasticizers, lubricant additives, coolants, metalworking cutting fluids, and sealants. This study investigated the spatial distribution, the potential pollution sources, and ecological risk of 24 short-chain CPs (SCCPs) and 24 medium-chain CPs (MCCPs) from 29 surface marine sediment samples from the East China Sea and Yellow Sea in September 2019. All of the 48 CPs were detected. The concentrations of SCCPs and MCCPs ranged from 0.703 to 13.4 ng/g dw and 0.0936 to 4.19 ng/g dw, respectively. C10 congeners showed the highest abundancy. The median concentrations of the SCCPs and MCCPs declined gradually with carbon atoms and chlorine atoms, except for Cl5 congeners. Spatial variations showed that all CP congeners in the East China Sea were larger than in the Yellow Sea and displayed a point-source-type distribution, which is consistent with the industrial park distribution. Although the potential ecological risk was at a relatively low level, bioaccumulation and trophic magnification could amplify the risk to marine organisms. Our results provide data support and theoretical assistance for SCCP and MCCP pollution control and sewage outlets in the East China Sea and Yellow Sea.

Planktonic cells are a vital part of biogeochemical nutrient cycling and play an extremely important role in maintaining the balance of water ecosystems. In this study, surface water samples were collected in three seasons (spring, summer, and winter) 10 km along the estuary of the Bailang River to assess the relationship between environmental factors and the bacterial community structure, which was determined by high-throughput sequencing. The physicochemical properties of the samples, including the pH, salinity, and inorganic nitrogen (NH4+, NO3−, and NO2−), exhibited significant seasonal variations, and the diversity and structure of the bacterial community also varied seasonally. A redundancy analysis showed that the inorganic nitrogen (NH4+, NO3−, NO2−), pH, and salinity are key factors in shaping the bacterial community composition. Among the different seasons, the core taxa of bacterial communities were the same, and Actinobacteria, Cyanobacteria, and Proteobacteria were the key components during the three seasons. The bacterial diversity and structure also varied seasonally, but there were no significant differences in spatial composition. Based on a phylogenetic investigation of communities by reconstruction of unobserved states analysis, nitrogen-cycle-related processes include four dominant processes: nitrogen mineralization, nitrogen fixation, dissimilatory nitrate reduction, and denitrification. These results suggest that the bacterial community structure in the waters of the Bailang River estuary is subject to seasonal rather than spatial variation. These findings provide new evidence for studies of the seasonal variation of bacterial communities in estuaries.

The Alqueva reservoir is essential for water supply in the Alentejo region (south of Portugal). Satellite data are essential to overcome the temporal and spatial limitations of in situ measurements, ensuring continuous and global water quality monitoring. Data between 2017 and 2020, obtained from OLCI (Ocean and Land Color Instrument) aboard Sentinel-3, were explored. Two different methods were used to assess the water quality in the reservoir: K-means to group reflectance spectra into different optical water types (OWT), and empirical algorithms to estimate water quality parameters. Spatial (in five different areas in the reservoir) and temporal (monthly) variations of OWT and water quality parameters were analyzed, namely, Secchi depth, water turbidity, chlorophyll a, and phycocyanin concentrations. One cluster has been identified representing the typical spectra of the presence of microalgae in the reservoir, mainly between July and October and more intense in the northern region of the Alqueva reservoir. An OWT type representing the area of the reservoir with the highest transparency and lowest chlorophyll a concentration was defined. The methodology proposed is suitable to continuously monitor the water quality of Alqueva reservoir, constituting a useful contribution to a potential early warning system for identification of critical areas corresponding to cyanobacterial algae blooms. [ABSTRACT FROM AUTHOR]

The forest ecosystem in Greater Khingan Mountains (GKM) is the largest primary forest in northern China. Accurate assessment of the regional carbon (C) pool of soils and analysis of the control factors are essential for setting appropriate forest management policies. Our study was designed to prove the hypothesis that forest soil acts as a C sink owing to continuous C accumulation, which results from constant biomass production within the GKM forests. We investigated topsoil (0-20 cm) C dynamics and diving force in GKM forests (both the Inner Mongolia and Heilongjiang sectors) based on field data from 2000 to 2019. The mean soil organic C density (SOCD) in the topsoil was 10.64 ± 0.83 kg C m-2 across the GKM, and the increase rate was 0.15±0.05 kg C m-2 y-1. Our results also demonstrated the critical role of precipitation and under vegetation diversity in shaping soil organic C dynamics across the GKM, suggesting that the relationship between the soil C cycle and temperature is unstable in northern ecosystems. Our results provided a new reference range for estimating surface soil C pools in GKM forests ecosystems based on field measurements. [ABSTRACT FROM AUTHOR]

Water is a primary element for human life on Earth. Fresh water, which includes rivers, lakes, streams, and ponds, contributes less than one thousandth of a percent of the total water on Earth, but it is critical for the environment and human life. Change in land use and land cover (LULC) is a foremost concern in global environment change. Rapid changes in LULC lead to the degradation of ecosystems and have adverse effects on the environment. There is an urgent need to monitor changes in LULC and evaluate the effects of these changes in order to inform decision makers on how to support sustainable development. This study used Moderate Resolution Imaging Spectroradiometry images to detect and investigate changes in LULC patterns in Gilgit-Baltistan, Pakistan, between 2008 and 2017. Six types of LULC were used to explain the major changes of LULC in the study area. The results showed that there was a reduction of barren lands and an increase of urban areas. It also showed an inconsistent behavior of water bodies during the study. Snow area, which also increased, needs further investigation. HIGHLIGHTS Comprehensive overview of six different LULC (barren, snow, urban, forest, water bodies, and wetlands) in Gilgit Baltistan were studied.; Representation of the variation in spatial, temporal, compositional, and configurational patterns of different LULC were assessed using MODIS data.; Trend analysis of LULC changes over the last decade was measured using the Mann–Kendall test and Sen's Slope Estimator.;

Summary: Background: Social determinants of health (SDOH) produce a broad range of life expectancy (LE) disparities. In China, limited literatures were found to report association between SDOH and LE at ecological level during a consecutive period of time from the spatial perspectives. This study aimed to determine the existence, quantify the magnitude, and interpret the association between SDOH and LE in China. Methods: Provincial-level LE were estimated from mortality records during 2005–2020 from National Mortality Surveillance System in China. A spatial panel Durbin model was used to investigate LE associated SDOH proxies. Spatial spillover effects were introduced to interpret direct and indirect effects caused by SDOH during long-term and short-term period on LE disparities. Findings: Nationwide, LE increased from 73.1 (95% confidence interval (CI): 71.3, 74.4) years to 77.7 (95%CI: 76.5, 78.7) years from 2005 to 2020. Unequally spatial distribution of LE with High-High clustering in coastal areas and Low-Low clustering in western regions were observed. Locally, it was estimated that SDOH proxies statistically significant related to an increase of LE, including GDP (coefficient: 0.02, 95%CI: 0.00, 0.03), Gini index (coefficient: 2.35, 95%CI: 1.82, 2.88), number of beds in health care institutions (coefficient: 0.02, 95%CI: 0.00, 0.05) and natural growth rate of resident population (coefficient: 0.02, 95%CI: 0.01, 0.02). Direct and indirect effects decomposition during long-term and short-term of LE associated SDOH proxies demonstrated that GDP, urbanization rate, unemployment rate, education attainment, Gini index, number of beds in health care institutions, sex ratio, gross dependence ratio and natural growth rate of resident population not only affected local LE, but also exerted spatial spillover effects towards geographical neighbors. Interpretation: Spatial variations of LE existed at provincial-level in China. SDOH regarding socioeconomic development and equity, healthcare resources, as well as population characteristics not only affected LE disparities at local scale but also among nearby provinces. Externalities of policy of those SDOH proxies should be took into consideration to promote health equity nationally. Comprehensive approaches on the basis of population strategy should be consolidated to optimize supportive socioeconomic environment and narrow the regional gap to reduce health disparities and increase LE. Funding: National Key Research & Development Program of China (Grant No.2018YFC1315301); Ministry of Education of China Humanities and Social Science General Program (Grant No.18YJC790138).

Summary: Background: Cardiovascular disease (CVD) is the leading cause of death (COD) in China. Understanding the characteristics of place of death (POD) among CVD deaths would be of great importance to evaluate the healthcare service utilization at the end stage of life. Limited studies have reported the POD distribution among CVD deaths, and little was known about the associated factors of hospital CVD deaths. Methods: By using data from National Mortality Surveillance System (NMSS) in China, this study presented the characteristics of POD distribution during 2008 and 2020. Afterwards, multilevel logistic regression was used to explore associated factors of hospital CVD deaths and quantify the magnitude to which the spatial variations of hospital CVD deaths could be explained by those associated factors. Findings: During 2008-2020, there was 7101871 CVD deaths collected by NMSS in China, with 77·13% home deaths and 18·49% hospital deaths. Shanghai (59·40%) had the highest percentage of hospital CVD deaths. Age, sex, ethnicity, marital status, education, occupation, underlying COD were significant influential factors of hospital CVD deaths. Spatial variations were shown at provincial level, with 33·88% of them being explained by factors at individual level. Interpretation: Home was the leading POD among CVD deaths in China, those CVD decedents characterized as the female, the youngest, Han population, the married, the retiree, lived in urban areas, with higher socioeconomic status and died of chronic CVDs had a higher probability of hospital deaths. Providing accessible and available healthcare services were priorities to improve quality of end-of-life care, significant variations among provinces and sub-population also reminded us of the requirements for equal healthcare resources allocation and multiple options for minorities of POD preference at the end stage of life. Funding: National Key Research & Development Program of China (grant number 2018YFC1315301)

Methods for the generation and application of process variation-aware compact models for silicon photonics are presented. Three categories of process variations are considered. First, systematic variations, including die-to-die and spatial variations, are addressed with parameterized variation-aware compact models, and demonstrated for coupled resonator optical waveguide variation impact and yield analysis. Second, methods for random variation are presented, with ensemble and adjoint-based variation modeling methods. Third, particle defects are addressed with an extension to adjoint methods, enabling efficient analysis and identification of photonic component areas that are sensitive to defects. Finally, methods for extraction of variation models using variation test chip design and measurement are presented. Together, these methods are key components toward design-for-manufacturability approaches to achieve high yield and high performance in photonic integrated circuit design. [ABSTRACT FROM AUTHOR]

Objective: Child undernutrition is a global public health problem with serious implications. In this study, we estimate predictive algorithms for the determinants of childhood stunting by using various machine learning (ML) algorithms.Design: This study draws on data from the Ethiopian Demographic and Health Survey of 2016. Five ML algorithms including eXtreme gradient boosting, k-nearest neighbours (k-NN), random forest, neural network and the generalised linear models were considered to predict the socio-demographic risk factors for undernutrition in Ethiopia.Setting: Households in Ethiopia.Participants: A total of 9471 children below 5 years of age participated in this study.Results: The descriptive results show substantial regional variations in child stunting, wasting and underweight in Ethiopia. Also, among the five ML algorithms, xgbTree algorithm shows a better prediction ability than the generalised linear mixed algorithm. The best predicting algorithm (xgbTree) shows diverse important predictors of undernutrition across the three outcomes which include time to water source, anaemia history, child age greater than 30 months, small birth size and maternal underweight, among others.Conclusions: The xgbTree algorithm was a reasonably superior ML algorithm for predicting childhood undernutrition in Ethiopia compared to other ML algorithms considered in this study. The findings support improvement in access to water supply, food security and fertility regulation, among others, in the quest to considerably improve childhood nutrition in Ethiopia. [ABSTRACT FROM AUTHOR]

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Water elements pollution has attracted public attention globally. Wuxi is located in East China, and its water source, Taihu Lake, has been severely polluted since 2007. Studies of elemental pollution profiles have yet to be conducted in this area. In this study, 56 water samples were collected in 2018, and 33 elements were determined using inductively coupled plasma-mass spectrometry (ICP-MS). The results showed that the levels of 33 elements ranged from 1.35 × 10–3 μg/L(Tl) to 101 mg/L(Ca), with Sr, Al, Fe, B, Ti, Ba, and Zn levels being relatively higher. A comprehensive literature review showed spatial distribution of conspicuous elements in drinking water worldwide. Meanwhile, Monte Carlo simulations were applied to evaluate exposure health risks. The total hazard index(HI) for 14 non-carcinogens and the average incremental lifetime cancer risk (ILCR) of As and Pb exposure through drinking water were found acceptable. Sensitivity analyses suggested that Sb and As in the drinking water represent an increasing risk to human health. The results of this study provide key data on local metal pollution characteristics, help identify potential risk factors, and contribute to the development of effective environmental management policies for Taihu Lake. [ABSTRACT FROM AUTHOR]

This paper deals with the spatial analysis of the educational performance measured by the average percentage Maths scores achieved in individual districts of Slovakia in Testing 9 during the school year 2018/2019. Besides identification of the spatial patterns in test scores achievements, the paper tries to investigate the impact of selected socio-economic variables (average nominal monthly wage and unemployment rate) onto the test scores achievements. Since we suppose the significant impact of the socially disadvantaged background onto the test results, corresponding dummy variable was taken into consideration as well. The ordinary least squares (OLS) estimation of the global linear regression model was followed by the local spatial approach using the geographically weighted regression (GWR) to capture the geographical variability of estimated parameters. Spatial variations in the relationship among the educational performance and the selected socio-economic variables were confirmed.

Following the unbalanced development and overexploitation of the countrychr('39')s watersheds, land fragmentation has become a major concern for the conservation of ecosystem services and land health. For this purpose, the present study was planned to evaluate and compare the landscape connectivity indices of KoozehTopraghi Watershed as one of the ecologically susceptible watersheds located in Ardabil Province. To this end, the landscape connectivity was investigated according to both structural and functional viewpoints, based on the green patches (rangelands and orchard) distributed at 36 sub-watershed areas. The mentioned indices were first calculated using the Fragstats Software and graph theory at each sub-watershed; then, they were standardized according to interval standardization between zero and one in order to consider the scale effect and draw a comparison in the same variation range. Therefore, the landscape connectivity was calculated, classified and mapped for each studied sub-watershed and the whole watershed. Structural connectivity results showed the high level of landscape connectivity between green patches in all studied sub-watersheds. In addition, the results showed that the landscape connectivity was obtained with the mean and standard deviation of 0.50 ± 0.52, being varied from 0.50 to 0.97. The results also proved that out of the 36 sub-watersheds located in the KoozehTopraghi, only 15 sub-watersheds had natural lands (orchard and rangelands). Also, the sub-watershed 27, with the highest value of landscape connectivity (0.97), had the highest priority.

We assayed the fatty acid composition of muscles of the northern pike Esox lucius Linnaeus, 1758 inhabiting the Gyda River, Siberia, Russia using gas-liquid chromatography. Of 43 fatty acids identified in the pike samples, 23 fatty acids accounted for 99.3% of the total content. The most abundant saturated fatty acids (SFA, 31.6%) were palmitic (C16:0, 20.0%) and stearic (C18:0, 7.3%) acids. Among monounsaturated fatty acids (MUFA, 15.1%), oleic acid (C18:1n9, 10.2%) and palmitoleic acid (C16:1, 4.1%) demonstrated the highest levels. The most represented polyunsaturated fatty acids (PUFA, 53.3%) were arachidonic acid (C20:4n-6, 7.6%), eicosapentaenoic acid (EPA, C20:5n-3, 7.3%), and docosahexaenoic acid (DHA, C22:6n-3, 26.3%). The fatty acid profile of specimens from the Gyda River was different in comparison to profiles found in other pike populations, most likely due to different diets. Pike flesh has good nutrition quality in terms of a low n-6/n-3 ratio (0.36), low atherogenic (0.39), and thrombogenic (0.22) indices, and a high ratio of hypocholesterolemic to hypercholesterolemic fatty acids (2.83), and this species can be recommended as a replacement or alternative to other fish sources in traditional diets.

Background: Traditional birth attendant utilization has become a common malpractice and a leading cause of maternal morbidity and mortality in the developing world, such as Ethiopia. Therefore, this study was aimed at determining the geospatial variation and determinant factors of traditional birth attendant utilization among mothers of reproductive age in Ethiopia., Methods: The data were taken from the 2019 Ethiopian Demographic and Health Survey. Arc GIS, Excel, and STATA-14 software were used for the data analysis. The adjusted odds ratio with a 95% confidence interval was used to declare significant determinants of traditional birth attendance among mothers of reproductive age in Ethiopia., Results: Among 5,753 mothers of reproductive age, 34.59% of them utilized traditional birth attendants in Ethiopia during the 2019 Ethiopian Demographic and Health Survey. There was a geospatial variation of traditional birth attendants among mothers of reproductive age in Ethiopia; the Global Moran's index value was 0.39 with a p -value <0.001. The significant factors associated with traditional birth attendant utilization were the age of mothers; higher odds were observed among older mothers aged 35-49 years (AOR = 1.31; 95% CI (1.04-1.63)); educational level of mothers (AOR = 3.04; 95% CI (2.13-4.33)); higher odds were observed in uneducated mothers, wealth index (AOR = 2.76; 95% CI (1.83-4.19)); higher odds were observed among the poorer and poorest households, place of residence (AOR = 5.69; 95% CI (3.35-9.67)); and the regions; the highest odds were observed in Somali (AOR = 12.1; 95% CI (4.99-25.68)) and Afar (AOR = 7.13; 95% CI (2.37-21.38))., Conclusions: The utilization of traditional birth attendants among reproductive-age mothers became a major public health concern, and the distribution showed geo-spatial variations among the regions of the country. We recommend taking appropriate measures to alleviate the current problem by improving access to maternal healthcare services., Competing Interests: The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article., (© The Author(s) 2024.)

The southern coast of Hainan Island, China, is one of the most frequently hit areas of tropical cyclones in the Northwest Pacific regions. Although some of the extreme typhoon events were known in historical times, quantitative information on the timing and magnitude of paleo-typhoon events in this coastal area remains rare. In the present study, a large number of coral reef boulders were found on the Xiaodonghai reef platform, on the south coast of Hainan Island. Morphometric analysis of the boulders shows an exponentially fining landward trend, indicating a storm origin; a wave-induced current velocity of 2.41–5.71 m/s during the storm events is required to transport the boulders that were originally situated outside the reef edge. Based on the U/Th and 14C dating for the age-indicating samples taken from the boulders, seven major periods with intense typhoon activities were identified for the last 4,000 years, i.e., 1800–1500 BCE, 1200–900 BCE, 50–120 CE, 550–800 CE, 900–1000 CE, 1350–1900 CE, and 1910–2000 CE. A comparison with the regional typhoon records in terms of climatic parameters in the northwestern Pacific and the South China Sea regions indicates that the longitudinal variations of intense typhoon frequency were mainly controlled by El Niño-Southern Oscillation (ENSO), dominantly modulated by the Intertropical Convergence Zone. Because of the future warming climate, there will be a trend of enhanced typhoon risk for the southern Hainan Island coasts.

Tidal creeks play a critical role in delivering water, suspended sediments, and nutrients to coastal wetlands, so it is important to understand the characteristics of the tidal creek system to guide the development and sustainable utilization of coastal wetlands. Using the coastal wetlands of the Liao River Estuary (LRE) as a study area, this study accurately divided the tidal flat based on the principle of tidal correction, extracted the linear features of tidal creeks using high-resolution remote sensing (RS) data, and then classified the tidal creeks on a tidal flat using the tidal creek ordering algorithm. Our study aimed to quantify the morphological characteristics of tidal creeks and qualitatively evaluate the parameters of the tidal creek network in the study area. The study results show obvious spatial heterogeneity in the order and the average length of tidal creeks in the coastal wetlands of the LRE. With the increase in the order of tidal creeks, the average length of tidal creeks increased exponentially and the number of tidal creeks decreased exponentially in the study area. The total density of tidal creeks was related to the beach surface elevation gradient, and the density and frequency of tidal creeks reduced substantially with an increase in the order of tidal creeks. The sinuosity ratio of tidal creeks declined sharply with a fall in the beach surface elevation gradient. The average bifurcation ratio of tidal creeks in the upper intertidal zone was higher than that in other zones, indicating that the tidal creeks in the upper intertidal zone were erratic. In addition, the hydrological connectivity of the tidal creek network in the upper intertidal zone and the development of the tidal creek system in the supratidal zone were the highest in the LRE. The study results help understand the spatial variations in tidal creek morphology under the influence of tidal hydrodynamics.

BACKGROUND: The conversion of arable land to grassland and/or forested land is a common strategy of restoration because the development of plant communities can inhibit the erosion of soil, increase biodiversity and improve associated ecosystem services. The vertical profiles of microbial communities, however, have not been well characterized and their variability after land conversion is not well understood. We assessed the effects of the conversion of arable land (AL) to grassland (GL) and forested land (FL) on bacterial communities as old as 29 years in 0–200‐cm profiles of a Chinese Mollisol. RESULTS: The soil in AL has been a stable ecosystem and changes in the assembly of soil microbiomes tended to be larger in the topsoil. The soil properties and microbial biodiversity of arable land were larger following revegetation and reforestation. The conversion caused a more complex coupling among microbes, and negative interactions and average connectivity were stronger in the 0–20‐cm layers in GL and in the 20–60‐cm layers in FL. The land use dramatically influenced the assembly of the microbial communities more in GL than AL and FL. The bacterial diversity was an important component of soil multinutrient cycling in the profiles and microbial functions were not as affected by changes in land use. CONCLUSION: The spatial variation of the microbiomes provided critical information on below‐ground soil ecology and the ability of the soil to provide crucial ecosystem services. © 2021 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

• The dynamics of CO 2 and CH 4 partial pressures are co-regulated by various nutrients. • CO 2 and CH 4 emission from lakes decreased and increased with longitude, respectively. • Freshwater lakes emit mainly CH 4 , while salt lakes are main contributor of CO 2. • NPP, NDVI and human activities enhance CH 4 emissions but reduce CO 2 emissions. Lakes are important component of the regional carbon cycle and a significant sources of greenhouse gases (GHGs) to the atmosphere. However, the regional variations in carbon dioxide (CO 2) and methane (CH 4) emissions, as well as the factors regulating these emissions are poorly constrained. To investigate the regional GHG emission from lakes and their potential influencing factors, we conducted field measurements in 13 lakes in Inner Mongolia from July to August 2020. We found that the studied lakes were predominantly sources of atmosphere CO 2 and CH 4. The CO 2 partial pressure (p CO 2) exhibited supersaturation in 80 % of samplings, but all samplings of CH 4 partial pressure (p CH 4) showed supersaturation. Moreover, the average p CH 4 is 40 times greater than that in the atmosphere. The lakes emitted substantial amounts CO 2 and CH 4 with average values of 25.8 ± 4.9 mmol m−2 d−1 and 2.1 ± 0.3 mmol m−2 d−1, respectively. At the regional scale, the dynamics of p CO 2 and p CH 4 are regulated by combination of various environmental factors. CO 2 emissions from studied lakes decreased with the catchment net primary productivity (NPP), normalized difference vegetation index (NDVI), and nighttime lights which is indicative of urbanization. Conversely, CH 4 fluxes increased with NPP, NDVI, and nighttime lights. We conclude that terrestrial carbon-cycling related variables and human activities significantly affect CO 2 and CH 4 emissions from lakes by transporting different nutrients, but they show opposite trends. Our results also exhibited that the freshwater lakes are the main contributors of CH 4 , while saline lakes are the main contributors of CO 2. We suggest that increased human activity leads to changes in terrestrial carbon-cycle related processes which affects lake carbon emissions by altering the amount of nutrients input to the lakes. [ABSTRACT FROM AUTHOR]

The digital economy (DE) has profoundly transformed social production and life. With its characteristics of high efficiency, high productivity, and low emissions, it plays a significant role in the low-carbon transition of the energy market (EM). This study scientifically evaluates the integration level between urban digital economy and energy market (DEI) using panel data from 281 Chinese cities between 2011 and 2020. The Dagum Gini coefficient, variance decomposition, and QAP methods are employed to analyze the spatiotemporal evolution characteristics and reveal the sources and formation mechanism of integration differences. The findings are as follows: ①The integration level between China's urban digital economy and energy market exhibits an apparent upward trend, but significant differences exist among the four major regions. ②Inter-regional disparities serve as the primary spatial source of the integration differences between China's urban digital economy and energy market. ③The difference in integration efficiency is the primary structural source of the integration differences, with the western and northeastern regions experiencing the greatest impact. ④The four structural-layer factors, namely integration efficiency, integration foundation, integration structure, and integration scale, contribute positively to integration differences, with the effect intensity decreasing in sequence. Accordingly, several policy implications derive. These include implementing targeted measures to address inter-regional disparities and promote balanced integration across different region, efforts to enhance integration efficiency in underperforming regions, and prioritizing investment in infrastructure to enhance the overall integration level. In conclusion, this study provides valuable insights into the integrated development between China's urban DE and EM, offering guidance for countries seeking to optimize DE and EM. [Display omitted] • An urban digital economy and energy market integration level (DEI) evaluation system is established. • China's urban DEI exhibits an apparent upward trend, but significant differences exist among the four major regions. • The inter-regional disparity is the primary spatial source of the differences in China's urban DEI. • Integration efficiency is the most significant structural source of China's urban DEI differences. • Integration efficiency, foundation, structure, and scale contribute positively toDEI, with decreasing effect intensity. [ABSTRACT FROM AUTHOR]

Abstract Background Accessibility and utilization of antenatal care (ANC) service varies depending on different geographical locations, sociodemographic characteristics, political and other factors. A geographically linked data analysis using population and health facility data is valuable to map ANC use, and identify inequalities in service access and provision. Thus, this study aimed to assess the spatial patterns of ANC use, and to identify associated factors among pregnant women in Ethiopia. Method A secondary data analysis of the 2016 Ethiopia Demographic and Health Survey linked with the 2014 Ethiopian Service Provision Assessment was conducted. A multilevel analysis was carried out using the SAS GLIMMIX procedure. Furthermore, hot spot analysis and spatial regressions were carried out to identify the hot spot areas of and factors associated with the spatial variations in ANC use using ArcGIS and R softwares. Results A one-unit increase in the mean score of ANC service availability in a typical region was associated with a five-fold increase in the odds of having more ANC visits. Moreover, every one-kilometre increase in distance to the nearest ANC facility in a typical region was negatively associated with having at least four ANC visits. Twenty-five percent of the variability in having at least four ANC visits was accounted for by region of living. The spatial analysis found that the Southern Nations, Nationalities and Peoples region had high clusters of at least four ANC visits. Furthermore, the coefficients of having the first ANC visit during the first trimester were estimated to have spatial variations in the use of at least four ANC visits. Conclusion There were significant variations in the use of ANC services across the different regions of Ethiopia. Region of living and distance were key drivers of ANC use underscoring the need for increased ANC availability, particularly in the cold spot regions.

Soil characteristics have spatial variations. Understanding spatial variations of soil characteristics is among the effective factors in sustainable land management. A better understanding the effects of management factors on soil characteristics need to quantify their heterogeneity and variability. This research was conducted with the aim of investigating spatial variations of some soil characteristics such as soil texture (clay, silt and sand), calcium carbonate (CaCo3), soil acidity (pH), and soil salinity using geostatistic methods. For this purpose, 252 soil samples (from 0 to 20 cm depth) were prepared from the study area and physical and chemical properties of soil were measured. After normalizing the data, the half-shift of each of the studied characteristics was calculated and the best model was fitted to them. Then, the characteristics of the study were estimated through different methods of conventional Kriging, simple Kriging, discrete Kriging and Inverse Distance Weighted (IDW) using ArcGIS software. The accuracy of the estimation was evaluated using the mean absolute error (MAE), the mean bias error (MBE), and the root mean square error (RMSE). The results showed that the best model for the acidity was the spherical model and for the other measured variables was the exponential model. Moreover, the conventional CoKriging method for clay, calcium carbonate and acidity (pH), IDW method for silt and soil salinity, and conventional Kriging method for sand were better than other methods used and provided more accurate estimates.

The hourly data of the vertical Z and the horizontal H components of 37 ground–based DC–ULF geomagnetic stations are examined during 20 April–12 May 2008. On 9 May 2008, three days before the Wenchuan MS 8.0 shock, anomalies — a double low-point and a decreased amplitude — are registered on the curves of the Z component at 25 stations in a large-scale area surrounding the Wenchuan epicentral area. The H component shows none of the double low-point phenomenon but does exhibit a reduced magnitude at the same time. The geomagnetic index Kp is also examined and indicates that the anomalies appear at a solar quiet period. The appearing time shift (Tzs) between the first low-point on May 9 and the minimum point occurring time of May 1–5, 2008 is also checked. The results show that Tzs is on the order of 1–2 hours earlier or later than usual and there is a 2–6 hours’ gap between these two low-points. However, there is still a transition area which includes the epicenter where Tzs = 0. Variation amplitude examined on vertical Z increases as the distance from the epicenter decreases. An Earth–air–ionosphere model has been employed to investigate a possible mechanism of this phenomenon and positive results have been unexpectedly attained. All these above-related results tend to prove that the variations of the Z and H on May 9, 2008 during the solar quiet period are probably associated with the forthcoming Wenchuan MS 8.0 earthquake.

Soil contamination produced by Cd and Pb released from vehicles is a serious environmental problem. Lead as a result of using leaded petrol fuels and cadmium in the car tire is introduced into the environment through vehicle depreciation and traffic. This study aimed to investigate the spatial distribution of heavy metals such as Pb and Cd at the roadside soils of Zabol - Zahedan route. 252 soil samples were taken from a depth of 0 -20 cm and the concentration of total lead and cadmium metals, physicochemical properties of soil including pH, EC and organic matter were measured. The contamination assessment of soil was done through using enrichment factor and geoaccumulation index. Metals’ spatial distribution maps for heavy metals concentration were used kriging methods. The mean concentration at 0, 50 and 100 meters, respectively, was 2.12, 2.03 and 2 mg kg-1 for lead, which is less than the global mean (25 mg kg-1) for this metal, and respectively 0.21, 0.21 and 0.20 mg kg-1 for cadmium, which was lower than the global average (0.53 mg kg-1). The results of the geospatial analysis showed that both variables were anisotropic and the exponential model for lead and Gaussian model for cadmium had the best fit.Interpolation map's analysis showed that the cadmium and lead has geological and human origins. In fact, these metals naturally exist in soils, but human activity has caused the accumulation of these metals in the soil.

Millimeter-wave (mm-wave) frequency range is among operating bands designated for terrestrial 5G networks. A critical challenge of link-budgeting in mm-wave 5G networks is the precise estimation of rain attenuation for short-path links. The difficulties are further amplified in tropical and subtropical regions where the rainfall rate has a higher intensity. Different models have been proposed to predict rain attenuation. The distance factor is an important parameter in predicting total attenuation from specific rain attenuation. This study investigates the distance factor based on rain gauge networks and measured rain attenuation at 26 GHz for a 300 m link in Malaysia. Considerable discrepancies between available models were observed especially when applied for shorter path links. Also, significant variability of rain intensity is observed from the rain gauge network. This study recommends further investigation of the distance factor for a shorter link. Hence, a measurement campaign incorporating rain gauge networks was established to examine spatial variations of rain intensity over a less than 1 km link. The motivation is to develop a suitable distance factor model for 5G mm-wave propagation. [ABSTRACT FROM AUTHOR]

The Alqueva reservoir is essential for water supply in the Alentejo region (south of Portugal). Satellite data are essential to overcome the temporal and spatial limitations of in situ measurements, ensuring continuous and global water quality monitoring. Data between 2017 and 2020, obtained from OLCI (Ocean and Land Color Instrument) aboard Sentinel-3, were explored. Two different methods were used to assess the water quality in the reservoir: K-means to group reflectance spectra into different optical water types (OWT), and empirical algorithms to estimate water quality parameters. Spatial (in five different areas in the reservoir) and temporal (monthly) variations of OWT and water quality parameters were analyzed, namely, Secchi depth, water turbidity, chlorophyll a, and phycocyanin concentrations. One cluster has been identified representing the typical spectra of the presence of microalgae in the reservoir, mainly between July and October and more intense in the northern region of the Alqueva reservoir. An OWT type representing the area of the reservoir with the highest transparency and lowest chlorophyll a concentration was defined. The methodology proposed is suitable to continuously monitor the water quality of Alqueva reservoir, constituting a useful contribution to a potential early warning system for identification of critical areas corresponding to cyanobacterial algae blooms.

The aim of the present study was to evaluate the spatio-temporal variability of various physical and chemical parameters of water quality and to determine the trophic state of Lake Ardibo. Water samples were collected from October 2020 to September 2021 at three sampling stations in four different seasons. A total of 14 physico-chemical parameters, such as water temperature, pH, dissolved oxygen (DO), electrical conductivity, turbidity, alkalinity, Secchi-depth, nitrate, ammonia, silicon dioxide, soluble reactive phosphorus, total phosphorus, chloride, and fluoride were measured using standard methods. The results demonstrated that temporal variation existed throughout the study period. Except for turbidity, the water quality of the lake varied significantly within the four seasons (ANOVA, p < 0.05). DO levels decreased significantly during the dry season following water mixing events. Chlorophyll-a measurements showed significant seasonal differences ranging from 0.58 μg L -1 in the main-rainy season to 8.44 μg L -1 in the post-rainy period, indicating moderate algal biomass production. The overall category of Lake Ardibo was found to be under a mesotrophic state with medium biological productivity. A holistic lake basin approach management is suggested to maintain water quality and ecological processes and to improve the lake ecosystem services., Competing Interests: The authors declare there is no conflict., (© 2024 The Authors This is an Open Access article distributed under the terms of the Creative Commons Attribution Licence (CC BY 4.0), which permits copying, adaptation and redistribution, provided the original work is properly cited (http://creativecommons.org/licenses/by/4.0/).)

Sea level changes play an important role as an indicator of climate change. However, without climate change, the sea level itself shows strong regional patterns, both in space and time, that could deviate significantly from global averages. The spatial variability of sea level changes in Indonesia can be divided based on its drivers, i.e., climatic and seasonal weather-driven and non-climatic and geological-driven. Seasonally, the sea level in Indonesia is generally high in northwest monsoon and low in southeast monsoon. Nevertheless, there is a possibility of extreme natural phenomenon influences that generate anomalies and a thermosteric process that also affects the sea level. On the non-climatic and geological theory, the uniqueness of the tectonic setting in Indonesia will create spatial variations in regional sea levels, as both static and dynamic changes in a long period of time. Land subsidence is also often regarded as a significant contributor to the rise of relative sea level in coastal environments. Combined with the rise in sea level, land subsidence will escalate coastal flooding risks, contribute to shoreline retreat, and be further aggravated by anthropogenic forces such as groundwater extraction and land development. This scientific review will summarize the spatial variation of sea level rise in Indonesia, examines the underlying drivers that control it, and provides an overview of the combined sea level rise and land subsidence as a significant threat in Indonesia.

The quality of air breathed in South Africa is of great concern, especially in industrialised regions where PM2.5 concentrations are high. Long term exposure to PM2.5 is associated with serious adverse health impacts. Traditionally, PM2.5 is monitored by a network of ground-based instruments. However, the coverage of monitoring networks in South Africa is not dense enough to fully capture the spatial variability of PM2.5 concentrations. This study explored whether satellite remote sensing could offer a viable alternative to ground-based monitoring. Using an eight-year record (2009 to 2016) of satellite retrievals (MODIS, MISR and SeaWIFS) for PM2.5 concentrations, spatial variations and temporal trends for PM2.5 are evaluated for the Vaal Triangle Airshed Priority Area (VTAPA). Results are compared to corresponding measurements from the VTAPA surface monitoring stations. High PM2.5 concentrations were clustered around the centre and towards the south-west of the VTAPA over the highly industrialised cities of Vanderbijlpark and Sasolburg. Satellite retrievals tended to overestimate PM2.5 concentrations. Overall, there was a poor spatial agreement between satellite-retrieved PM2.5 estimates and ground-level PM2.5 measurements. Root mean square error values ranged from 6 to 11 µg/m3 and from -0.89 to 0.32 for the correlation coefficient. For satellite remote sensing to be effectively exploited for air quality assessments in the VTAPA and elsewhere, further research to improve the precision and accuracy of satellite-retrieved PM2.5 is required.

Abstract The characteristics of the southwest monsoon (SWM) rainfall over Myanmar were studied using APHRODITE gridded daily rainfall datasets for the period 1951–2010. Myanmar, being an agrarian economy, is predominantly dependent on the SWM rainfall. The spatial distribution of rainfall (rainy days) has shown higher rainfall of 2,000 mm (>140 rainy days) over southwest parts, rainfall of ~1,000 mm (100–120 days) over north and eastern parts and an arid zone with rainfall of less than approximately 500 mm (

Abstract In the inner area of the Sea of Ariake, rearing experiments were conducted to examine how the survival rates of juveniles of three bivalve species (Anadara kagoshimensis, Ruditapes philippinarum, Atrina sp.) vary among sea areas and heights above the seabed. In three runs of the experiment, replicate samples of the three bivalves were kept in trays set at various heights above the seabed (range 0–40 cm) at one to six stations for 15–16 days. Results were as follows. (1) Survival rates varied among heights and stations more markedly for Atrina sp. than for A. kagoshimensis and R. philippinarum; (2) Atrina sp. always showed higher survival rates at greater heights above the seabed, whereas the other species did not always show this pattern. (3) Survival rates of Atrina sp. showed a different station-to-station variation pattern between experimental runs. (4) In statistical model selection, the spatial variations in the survival rate were not associated for either A. kagoshimensis or R. philippinarum with any of the environmental factors recorded (density of suspended solids, density of chlorophyll a, water temperature). In contrast, for Atrina sp. they were strongly and negatively associated with the spatial variations in density of suspended solids.