Sampling Sites Research Articles

Trace element partitioning between natural barite and deep anoxic groundwaters: Implications for radionuclide retention in host rocks of nuclear waste repositories.

Safety assessments for deep geological repositories involve risk calculations for the release of radionuclides like Ra, U, Pu and trivalent actinides from the storage containers to the groundwater. The retention of radionuclides through water-mineral interaction along the groundwater flow path could be a crucial factor in case of a repository failure. Barite (BaSO4) assumes significance in this context, as it has the potential to (re)crystallize and incorporate significant quantities of radioactive elements under relevant physico-chemical conditions.The assessment of mineral-fluid partition coefficients provides a means to evaluate the uptake potential of elements into the mineral. Usually, partition coefficients are determined under well-defined and controlled experimental conditions in laboratories. However, these results have shown discrepancies to partitioning coefficients determined from natural systems.Furthermore, effects like diagenesis or changes in the chemical fluid parameters might lead to a secondary alteration of the phases and affecting the retention ability.Here we investigate the incorporation of trace elements in natural barite from a borehole at 415 m depth in the Äspö Hard Rock Laboratory (Sweden). High-resolution LA-ICP-MS enables the quantitative determination of field-based partition coefficients through the integrated pixel average of selected zones in element distribution maps, combined with existing fluid concentration data. Similarities between the solid solution systems (Ra,Ba)SO4 and (Sr,Ba)SO4 allowed the combination of Sr partitioning data with density-functional theory simulations for an estimation of the partition coefficient value for Ra in natural barite. Values in the 10-2 range were determined, showing a deviation from those reported in previous experimental studies in the 100 range.Moreover, lanthanum serves as an analogue element for the radioactive trivalent actinides. The partition coefficient values for La in natural barite were determined in the range of 10-2 and 10-1, aligning well with experimental partition coefficients. Although density functional theory simulations cannot directly convert a La partition coefficient into a partition coefficient for trivalent actinides, it is assumed that these elements exhibit comparable behavior. Besides primary growth zonation, La also exhibits strong secondary enrichment, probably resulting from groundwater mixing and late fluid-mediated element transport through connected intracrystalline pore space oriented at cleavage plane systems. Additional SIMS analysis provides insights into the temporal variation of the sulphate source at the sampling site reflecting the influence of different waters during mineral growth.This study demonstrates a discrepancy between natural and synthetic PRa for barite and emphasizes that secondary processes significantly impact radionuclide retention in barite. Including these effects in reactive transport models will improve the reliability and applicability of integrative risk models.

Comparative evaluation of swabbing sites for Omicron variant detection in PCR testing

PurposeThe Omicron variant of SARS-CoV-2 raised concerns about the best sampling sites for PCR testing, with early indications suggesting throat swab samples were better than nasal swab samples. Our study evaluated the sensitivity of detecting SARS-CoV-2 across different swabbing sites. MethodsParticipants undergoing testing at NHS Test and Trace sites in England provided self-collected samples using nose only, throat only, and combined nose and throat swabs, which were analysed by realtime PCR. ResultsAmong 815 participants, combined swabs had higher viral concentrations than nose or throat only swabs. Sensitivity was 91% for nose only and 97% for throat only, relative to the combined approach. VC remained stable in nose swabs but declined in throat swabs with time. ConclusionsCombined nose and throat swabs are the most effective for SARS-CoV-2 detection, including Omicron, though individual swabs are viable alternatives. VC variations highlight the importance of sampling sites for accurate diagnosis.

Nation-wide monitoring campaign of 49 biocides and surfactants in surface waters and wastewaters

Despite their intensive use and their impact on ecosystems, biocides and surfactants are still poorly regulated and poorly monitored at large scale. In the frame of the revision of the national regulatory surveillance plan of surface waters, France planned in 2018 a monitoring campaign at national scale focused on these two types of substances of very emerging concern. Forty-nine contaminants (32 biocides and 17 surfactants) were investigated in surface water and sediment samples from 91 sampling sites, and in effluent and sludge samples of 7 wastewater treatment plants (WWTP), in mainland France and overseas regions. Between 33 and 52 % of the target contaminants were quantified at least once in water and sediment. High frequencies of quantification were observed for the surfactants (up to 91 % in water samples and up to 57 % in sediment samples for LAS C10-C13) and for the biocides (up to 64 % for fipronil in water samples and up to 90 % for methyl nonyl ketone in sediment samples). The median concentrations of surfactants were up to 2 μg/L in mainland surface water samples and up to 528 μg/kg in sediment samples, and for biocides, the median concentrations were up to 0.18 μg/L in mainland surface water samples and up to 104 μg/kg in sediment samples. PNEC exceedances in water and sediment were determined for both types of substances. The analysis of effluent and sludge suggested significant but not total removal of these substances in the WWTP. Temporal and spatial variations of the concentrations of both types of substances in surface water samples were also observed, suggesting both punctual and diffuse contamination sources of the surface water investigated.

The species diversity and phylogenetic structure patterns of desert plant communities in the Turpan-Hami region, Xinjiang

Desert plant communities play a crucial role in enhancing desert ecosystem productivity and stability but are highly susceptible to environmental changes owing to their limited resilience and resistance to disturbances, making it essential to understand the factors influencing their diversity patterns and community structure, particularly under the threat of climate change and intensifying droughts. This study focused on the Turpan-Hami desert region, a typical desert ecosystem in which diversity patterns and community structures remain unclear. We established 101 sampling sites ranging from elevations of -134 to 2056m and recorded community information, including species composition, height, coverage, and density, using the sample plot method. The diversity patterns were analyzed using regression analysis, and the phylogenetic structure was assessed. Additionally, Canonical Correspondence Analysis, Mantel tests, and General Linear Models were used to identify the key factors affecting community structure. Our results demonstrated that the species richness and phylogenetic diversity of plant communities exhibited a monotonic increase with elevation, and the phylogenetic structure exhibited low clustering and high dispersion along the elevational gradient. The annual mean temperature emerged as the most significant factor influencing diversity patterns, with soil nutrients, such as total potassium and available phosphorus, also affecting the spatial distribution of diversity. Notably, no significant correlations were found between community phylogenetic structure and abiotic factors, highlighting the complex interactions that drive diversity in the Turpan-Hami region. This study offers valuable insights into the mechanisms shaping desert plant community diversity and is essential for biodiversity conservation efforts in fragile desert ecosystems amid climate change.

Variability of the Microbiota in Chronic Rhinosinusitis: A Scoping Review.

Chronic rhinosinusitis (CRS) is characterized by a persistent inflammation of the nasal and paranasal sinus mucosa that could be potentially linked to a dysregulation between the microbiota and the immune system. We aim to explore general, methodological, and microbiological aspects of microbiota research in CRS compared to disease-free individuals. Embase, Ovid MEDLINE, PubMed, Scopus, and Web of Science. All studies comparing the composition of the resident microbiota of the sinonasal cavities in 2 groups: CRS and normal participants. We conducted systematic study selection, data extraction, and analysis first using the title and abstract, and then the full texts based on predefined inclusion and exclusion criteria. Compiled and presented findings include sampling site and technique, and microbiological results such as the relative abundance and the variability of the composition of the microbiota in both groups. Twenty-seven studies, using genomic identification with 16s RNA were analyzed. Case definitions primarily followed EPOS or AAO-HNS guidelines, with endoscopic swabs (82%), and middle meatus sampling (74%) being prevalent techniques. Despite relative abundance variability, patterns emerged across studies, indicating an increase in Haemophilus (19%) and Pseudomonas (11%), and decrease in Propionibacterium (15%) and Anaerococcus (11%). Another pattern was observed, showing a decreased alpha diversity (6/19; 22%) in CRS compared to normal individuals. While variations exist among studies, analysis of CRS microbiota suggests an association with dysbiosis, potentially contributing to chronic inflammation. Future research must prioritize standardized criteria for diagnostics and patient selection, fostering a more comprehensive understanding of CRS microbiota.

Compositional-geochemical characterization and multi-element pollution and risk assessment of potentially toxic elements in the urban landfill soil

Urban areas are characterized by the presence of various pollution sources including landfills. During the recent decade, urban landfills were investigated as a source of pollution by potentially toxic elements and potential deposits for landfill mining. The contents of Cr, V, Ti, Ca, K, Mo, Zr, Sr, Rb, As, Zn, Cu, Co, Fe, Mn, Pb, Ba in soils of Vanadzor city landfill site (VL) were determined using the X-ray fluorescence spectrometer to assess multi-element pollution and ecological risk and to identify potentially toxic elements geochemical associations through the application of compositional data analysis. The results showed that Cr, Mo, Zn, Cu, and Pb displayed significant values (>100%) of coefficient of variation suggesting their anthropogenic origin. Moreover, these elements, except Cr, displayed outliers and extreme values in the same sampling sites located directly on the reclaimed part of the landfill. The median contents of Zn, Pb, Cu, Cr, Cd, and As exceeded the global median values by 8.2, 9.8, 19.0, 4.6, 6.1, and 4.5 times, respectively. The multi-element pollution assessment showed that an extremely hazardous level of pollution was observed on the reclaimed part of the VL. From this site, a trend of decrease in the pollution level was observed in the eastern and western directions. In contrast, an allowable level of pollution was observed in the northern part - toward the direction of the above-located hill. The VL was found to be in an inferior ecological condition (a very high level of potential ecological risk was observed), which might also have a negative impact on the ecosystems located in its vicinity. The hierarchical clustering has revealed that the studied elements are grouped in two geochemical associations: a naturally formed - Co, Fe, V, Ti, Mn, Sr, Zr, Rb, K, Ba, As; and an anthropogenic one - Zn, Pb, Cu, Ca.

Prevalence and distribution of trematodes hosted by Bithynia siamensis in Southern Thailand.

This study aimed to investigate the occurrence of larval trematode infections in bithyniid snails across five provinces in southern Thailand. A total of 1,413 Bithynia siamensis snails were collected between October 2021 and October 2022 using handpicking and scooping methods. Among these, 844 were identified as B. s. siamensis and 569 as B. s. goniomphalos. The snail samples were examined for parasitic infections in the laboratory using shedding and crushing methods. Among the 27 sampling sites, snails from 6 sites were infected with various trematode species (infection rate: 4.95%, 70/1,413). Evaluation of the morphological and internal organ characteristics of the cercariae allowed for the categorization of the trematodes into five species of trematodes (belonging to four families). The identified species included Echinochasmus pelecani (family: Echinostomatidae), Echinostoma revolutum (family: Echinostomatidae), Haematoloechus similis (family: Haematoloechidae), Loxogenoides bicolor (family Lecithodendriidae), and Stictodora tridactyla (family: Heterophyidae), and the infection rates for these species were 3.26% (46/1,413), 0.35% (5/1,413), 0.42% (6/1,413), 0.78% (11/1,413), and 0.14% (2/1,413), respectively. The cercariae from the identified trematode species were studied for DNA analysis. The phylogenetic lineage reveals relationships among the species, confirming the morphological distinctions.

Cutaneous tissue samples show significant shrinkage during histopathological work-up: a real-world study.

Excision and histological examination of cutaneous neoplasms are very common diagnostic and therapeutic procedures in dermatological practice. There are often discrepancies between tissue seize in vivo and after histopathological work-up. This may raise questions according to tumor sizes or safety margins. To investigate the effect of excision and histological processing on the properties of cutaneous neoplasms in real-life 401 specimens in 324 patients were prospectively investigated. Delineated excision margins of cutaneous neoplasms were documented prior to (T0) and post excision (T1). Length, width and thickness were measured after ≥48 h of formalin fixation (T2) and after sectioning (T3) on final histological slices. Accompanying parameters such as patient age, gender, anatomical site, and tumor entity were evaluated. All post-processed tissue exhibited a significant (P<0.001) median (interquartile range) reduction in length, width and thickness of 21.0% (9.5-30.0), 30.7% (20.0-40.0), and 28.0% (4.8-46.7), respectively, irrespective of site, patient age or tumor entity. Maximum median (IQR) reduction for the length and the width was observed right after excision (17.0% [4.3-25.0] and 14.0% [11.1-28.6] reduction). No significant median (IQR) tissue changes between T1 and T2 were observed (length: 4.8% (-4.3-13.3); width: 0% (-17.6-11.1); thickness 0% (-32.0-20.0). Subgroup analyses showed significantly greater tissue shrinkage in younger patients and for tissue sample sites (trunk or lower extremities). Most relevant shrinkage of cutaneous samples occurs right after excision. Age- and site-depended tissue contractility can influence these effects. Formalin fixation does not affect tissue shrinkage. Smaller tissue sizes on histopathological reports are to be expected.

Exploring the pathways of urban green space exposure on respiratory health: An empirical study in Nanjing, China

Pathways of association between green space (GS) exposure and respiratory health continue stimulating scholars' research interest. However, the mechanisms underlying the multidimensional association between GS exposure and respiratory health remain to be clarified. Therefore, this study aimed to construct a research framework for exploring the mechanisms affecting the hypothesized pathways (physical activity, air pollution) based on the dynamic quantification of multidimensional exposure indicators (spatial and visual exposure). This study used urban green spaces in Nanjing, China, as sample sites for a pilot experiment. The parallel mediating effect of GS exposure on respiratory health through physical activity and air pollution was explored by partial least squares (PLS) modeling, and the effect of differences in GS exposure levels on this parallel mediating model was explored. The results showed that a dynamic monitoring system of multiple indicators is more conducive to characterizing the actual GS exposure of the population. Promoting physical activity and reducing air quality were both mediating pathways affecting GS exposure and respiratory health, with physical activity being the most critical mediating variable, accounting for 43.06% and 51.02% of the total indirect effects, respectively. And variables such as age, BMI, and gender do not affect the mechanism. The respiratory health-promoting benefits of performing short-term exposure in urban green spaces had a lagged effect of at least 4hours. The results of this study will help environmental epidemiologists to elucidate the pathways and mechanisms by which the green space system affects respiratory health and provide evidence for local governments to implement efficient and respiratory-healthy green space planning and design.

Determination of the Iron and Zinc Contents for Teff Types in The NorthWestern Part of Ethiopia

A simple and efficient method was used to determine the levels of iron and zinc in the teff flour samples. The aim of this study was to determine the concentration levels of iron and zinc in teff samples across different locations and to compare with other reported values due to different agricultural applications. The levels of Fe and Zn in the three types of teff samples collected from the three sampling areas were determined by using Micro-plasma atomic emission spectroscopy. The iron mean concentration of white teff was highest in the Bure site followed by Bahir Dar and Debre Markos sampling sites. The level of iron in the red teff was highest in the Debre Markos site followed by Bure and Bahir Dar sampling sites respectively. Similarly, the iron content of the mixed teff was highest in Bahir Dar site followed by Debre Markos and Bure sampling sites. However, the amounts of Zn determined in the three types of teff samples collected from the three different locations were almost similar. The overall mean concentrations determined (mg/kg, air dry weight) for the teff samples collected from the Bure, Debre Markos and Bahir Dar sites were in the ranges of Fe (719) &gt; Zn (86) &gt;, Fe (728) &gt; Zn (87) and Fe (668) &gt; Zn (73), respectively. The one way ANOVA indicated the mean concentrations of the two studied metals found in the three types of teff samples within and between the sampling sites was not significant at 95% confidence level.

Response of Plant Endophyte Communities to Heavy Metal Stress and Plant Growth Promotion by the Endophyte Serratia marcescens (Strain JG1)

Effects of heavy metals on soil microbial communities have been extensively studied due to their persistence in the environment and imposed threats to living organisms; however, there is a lack of in-depth studies of the impacts of heavy metals on plant endophyte communities. Therefore, the responses of plant endophyte communities to different concentrations of heavy metals were investigated in this study. The endophyte communities of plants existing in severely (W1, Pb, 110.49 mg/kg, Cd, 1.11 mg/kg), moderately (W2, Pb, 55.06 mg/kg, Cd, 0.48 mg/kg), and mildly (W3, Pb, 39.06 mg/kg, Cd, 0.20 mg/kg) contaminated soils were analyzed by 16s rRNA high-throughput Illumina sequencing. Furthermore, networks were constructed to illustrate the relationships between microorganisms and environmental factors. High-quality sequences were clustered at a 97% similarity level. Results revealed that the diversity of the community and relative abundance of Cyanobacteria phylum increased with decreasing levels of pollution. Cyanobacteria and Proteobacteria were found to be the dominant phylum, while Methylobacterium and Sphingomonas were observed as the dominant genus. Tukey’s HSD test showed that the relative abundances of Cyanobacteria and Proteobacteria phyla and Methylobacterium and Sphingomonas genera differed significantly (p &lt; 0.01) among the plants of the three sample sites. Environmental factor analysis revealed a significant negative correlation (p &lt; 0.01) of Cyanobacteria and a significant positive correlation (p &lt; 0.01) of Methylobacterium with the heavy metal content in the environment. These findings suggest that Cyanobacteria and Methylobacterium may be phylum and genus indicators, respectively, of heavy metal toxicity. Tax4Fun analysis showed the effect of heavy metal toxicity on the abundance of genes involved in plant metabolism. In addition, culturable endophytic strains were isolated to study their resistance to heavy metal stress and their ability to promote plant growth. The potting tests showed that the JG1 strain was tolerant to heavy metals, and it could significantly promote the growth of the host plant under stress caused by multiple heavy metals. Compared to the control, the JG1-treated plants showed a 23.14% increase in height and a 12.84% increase in biomass. Moreover, AP, AK, and HN contents in JG1-treated plants were 20.87%, 12.55%, and 9.03% higher, respectively, under heavy metal stress. The results of this study provide a scientific basis for the construction of an efficient plant endophyte restoration system.

Mosquitoes on a chip-environmental DNA-based detection of invasive mosquito species using high-throughput real-time PCR.

The monitoring of mosquitoes is of great importance due to their vector competence for a variety of pathogens, which have the potential to imperil human and animal health. Until now mosquito occurrence data is mainly obtained with conventional monitoring methods including active and passive approaches, which can be time- and cost-consuming. New monitoring methods based on environmental DNA (eDNA) could serve as a fast and robust complementary detection system for mosquitoes. In this pilot study already existing marker systems targeting the three invasive mosquito species Aedes (Ae.) albopictus, Ae. japonicus and Ae. koreicus were used to detect these species from water samples via microfluidic array technology. We compared the performance of the high-throughput real-time PCR (HT-qPCR) system Biomark HD with real-time PCR (qPCR) and also tested the effect of different filter media (Sterivex® 0.45 µm, Nylon 0.22 µm, PES 1.2 µm) on eDNA detectability. By using a universal qPCR protocol and only 6-FAM-MGB probes we successfully transferred these marker systems on the HT-qPCR platform. All tested marker systems detected the target species at most sites, where their presence was previously confirmed. Filter media properties, the final filtration volume and observed qPCR inhibition did not affect measured Ct values via qPCR or HT-qPCR. The Ct values obtained from HT-qPCR were significantly lower as Ct values measured by qPCR due to the previous preamplification step, still these values were highly correlated. Observed incongruities in eDNA detection probability, as manifested by non-reproducible results and false positive detections, could be the result of methodological aspects, such as sensitivity and specificity issues of the used assays, or ecological factors such as varying eDNA release patterns. In this study, we show the suitability of eDNA-based detection of mosquito species from water samples using a microfluidic HT-qPCR platform. HT-qPCR platforms such as Biomark HD allow for massive upscaling of tested species-specific assays and sampling sites with low time- and cost-effort, thus this methodology could serve as basis for large-scale mosquito monitoring attempts. The main goal in the future is to develop a robust (semi)-quantitative microfluidic-based eDNA mosquito chip targeting all haematophagous culicid species occurring in Western Europe. This chip would enable large-scale eDNA-based screenings to assess mosquito diversity, to monitor species with confirmed or suspected vector competence, to assess the invasion progress of invasive mosquito species and could be used in pathogen surveillance, when disease agents are incorporated.

RESEARCH OF THE POSSIBILITY OF USING CHP ASH IN THE PRODUCTION OF FIRED ASH GRAVEL

The article presents a comparative analysis of the characteristics of the dump ash of the Kyzylorda CHP hydraulic removal. A huge amount of ash, slag waste is collected in the dumps of the CHP, their accumulation in the dumps leads to a violation of the ecology of the environment. The issue of ash, slag waste disposal is an urgent problem. The use of ash and slag not only solves the issue of availability of raw materials, but also allows to improve the quality of products while reducing their cost. One of the valuable components of ash and slag waste is hydraulic removal ash. Hydraulic removal ash as a raw material can be used for the manufacture of artificial concrete aggregates (ash, agglomerate gravel, etc.). Studies were conducted to study the physico-chemical composition, determine the specific effective activity of natural radionuclides, loss during calcination of two types of hydraulic removal ash samples from Kyzylorda CHP (black and gray), which differ in sampling sites from ash dump. When studying the properties of the ash, X-Ray phase analysis was carried out, with the help of which the phase composition of the ash was determined. Work was carried out on the X-Ray phase analysis of ash, determination of the specific effective activity of natural radionuclides, calcination losses, which showed the possibility of using ash for the production of building materials. The conducted studies have confirmed the expediency of using the ash of the Kyzylorda thermal power plant in the production of fired ash gravel.

Diversity of Anuran Amphibian Using Visual Encounter Survey Method Implemented in Three Different Habitats

Amphibian diversity in the study area of Karode Village is located in Vilavancode Taluk of Kanniyakumari District, Tamilnadu, and was surveyed for three months and 12 weeks nights between October to Dec 2024. The amphibians were surveyed during day and night sessions using the visual encounter survey (VES) method at three sampling sites. A total 4 species were recorded, comprised of 3 families. This study contributed of amphibians at despite limited sampling time and sampling outside of the breeding peak. The information generated from this study could be utilised for conservation and long-term monitoring of amphibians of the lowland.

Pollen atlas from bat guano deposits in southeastern Amazonia

The botanical literature lacks pollen resources such as atlases and identification keys for bat guano deposits. To address this gap, our dataset describes modern pollen and spore assemblages from five caves in the Carajás region, southeastern Amazonia. A comprehensive atlas featuring illustrations and detailed descriptions of pollen and spores was created using both original and published data. It aims to simplify the identification of different pollen and spores taxa within bat guano deposits, featuring light micrographs and descriptions of 105 pollen taxa, including 81 arboreal and shrub taxa, 11 lianas taxa, 7 herbaceous taxa, 3 palm taxa, and 3 ferns. Among the total pollen assemblage, entomophilous plant taxa represented 42.8%, followed by wind-pollinated taxa at 9.5% and bat-pollinated taxa at 7.6%. Our data indicate that bat guano can provide valuable information on plant taxa that are underrepresented in more traditional pollen sampling sites such as peat bogs and lake sediments.

Differential microbiome features in lake-river systems of Taihu basin in response to water flow disturbance.

In riverine ecosystems, dynamic interplay between hydrological conditions, such as flow rate, water level, and rainfall, significantly shape the structure and function of bacterial and microeukaryotic communities, with consequences for biogeochemical cycles and ecological stability. Lake Taihu, one of China's largest freshwater lakes, frequently experiences cyanobacterial blooms primarily driven by nutrient over-enrichment and hydrological changes, posing severe threats to water quality, aquatic life, and surrounding human populations. This study explored how varying water flow disturbances influence microbial diversity and community assembly within the interconnected river-lake systems of the East and South of Lake Taihu (ET&ST). The Taipu River in the ET region accounts for nearly one-third of Lake Taihu's outflow, while the ST region includes the Changdougang and Xiaomeigang rivers, which act as inflow rivers. These two rivers not only channel water into Lake Taihu but can also cause the backflow of lake water into the rivers, creating distinct river-lake systems subjected to different intensities of water flow disturbances. Utilizing high-throughput sequencing, we selected 22 sampling sites in the ET and ST interconnected river-lake systems and conducted seasonally assessments of bacterial and microeukaryotic community dynamics. We then compared differences in microbial diversity, community assembly, and co-occurrence networks between the two regions under varying hydrological regimes. This study demonstrated that water flow intensity and temperature disturbances significantly influenced diversity, community structure, community assembly, ecological niches, and coexistence networks of bacterial and eukaryotic microbes. In the ET region, where water flow disturbances were stronger, microbial richness significantly increased, and phylogenetic relationships were closer, yet variations in community structure were greater than in the ST region, which experienced milder water flow disturbances. Additionally, migration and dispersal rates of microbes in the ET region, along with the impact of dispersal limitations, were significantly higher than in the ST region. High flow disturbances notably reduced microbial niche width and overlap, decreasing the complexity and stability of microbial coexistence networks. Moreover, path analysis indicated that microeukaryotic communities exhibited a stronger response to water flow disturbances than bacterial communities. Our findings underscore the critical need to consider the effects of hydrological disturbance on microbial diversity, community assembly, and coexistence networks when developing strategies to manage and protect river-lake ecosystems, particularly in efforts to control cyanobacterial blooms in Lake Taihu.

CHARACTERIZATION AND CLASSIFICATION OF SOILS DEVELOPED ON COASTAL PLAIN SOILS FOR CROP PRODUCTION IN ORON LGA, SOUTH- SOUTH, NIGERIA

Soils are characterized and classified based on its unique properties. Detailed characterization of four representative areas of Oron coastal plain soils in South –South, Nigeria was carried out. Soil samples were collected from pedogenic horizons of soils in four sampling sites. Routine analysis of soil properties was carried out in the laboratory with standard laboratory procedures. Soil data was subjected to descriptive statistics using statistical analytical system. The soils have a deep well drafted profile of about deep 200 cm. The soil texture varied in areas ranging from loamy sand to sandy loam, sandy and sandy clay loam while bulk density increased down the natural horizons. The pH varied between moderately acidic to strongly acidic in the soils of the study area. The morphology of soils ranged in various colour matrix of hues (10-7.5) and Chroma values (1-8) in all horizons. The soils were characterized by Dark Brown (10YR3/3), Dark Greyish Brown (10YR4/2) and Yellowish Brown (10YR 5/4) to Grey (7.5YR6/2). The soils had low concentrations of exchangeable cations (Ca, Mg, Na and K). The Coefficient of variation (CV%) values ranged from 0.74 to 91.6 in Ca, Mg, Na and K. All the parameters in the soils of the study area showed low and medium mean values except soils of Esin Ufot1 and 2 which showed high mean values of Na with Esin Ufot 2 having the highest mean value of sodium to be 0.18 Cmol/kg. Suborder soils were classified as Grossarenic Kandiaqualfs (CEC &gt; 16 Cmol/kg) for Esin Ufot1.Esin Ufot2, Esuk Oron1 while Esuk Oron 2 were classified as Typic Kandaquults (CEC &lt; 16 Cmol/kg). A great importance in providing adequate data to enable right decision taking in the choice of site for developmental projects and crop production.

Soil Nutrients Inversion in Open‐Pit Coal Mine Reclamation Area of Loess Plateau, China: A Study Based on ZhuHai‐1 Hyperspectral Remote Sensing

ABSTRACTSoil nutrients are crucial to assess land reclamation quality, and the use of various types of remote sensing data for soil nutrient inversion has been a key focus for soil monitoring. However, fewer studies have been conducted using satellite‐based hyperspectral remote sensing. To explore the potential of satellite‐based hyperspectral remote sensing in soil nutrient monitoring, this study selected soil organic matter, total nitrogen, available phosphorus, and available potassium content data from 83 sample sites using ZhuHai‐1 hyperspectral data. After spectral transformation and feature extraction, various inversion models were constructed, including partial least squares regression, support vector machine, recurrent neural network, and random forest. After verification by accuracy, the best spectral‐model combination was used for inversion. The results showed that the R‐squared range of the inversion models was 0.67748–0.78115. High content areas of soil organic matter and available potassium exhibited concentrated and contiguous features, while high content areas of total nitrogen and available phosphorus were more fragmented and fine‐grained. Alfalfa grassland plays a vital role in improving reconstructed soil in the early reclamation stage, and agricultural activities have differential impacts on soil nutrient accumulation. This study provides a theoretical basis for verifying the application capability of ZhuHai‐1 hyperspectral satellite data in soil monitoring.

Using Tillandsia usneoides as Biomonitor for Toxic Metals in the Air of Guanajuato's Tunnel Network

Guanajuato town is an important touristic center of Mexico, and one of its main attractions is its tunnel network (subterranean streets). In this work the air quality inside this tunnel network was evaluated using samples of Tillandsia usneoides as a biomonitor. Twenty-one plastic passive samplers, containing 50 g of plants each, were installed at different points of this tunnel network. In addition, surface layer of the tunnel walls, close to the plant sampling sites, were collected. Estimates for the enrichment factor, using Fe as reference and standard metal crustal data, suggest that the origin of the suspended metals is probably geogenic for Cr, a mix for Cu, and anthropogenic for Zn and Hg. It is important to emphasize that the Guanajuato’s tunnel network is used both by pedestrians and vehicular traffic and, probably, the last one is acting as the main source for toxic elements for the tunnel’s air.

Altitudinal Variation in Soil Acid Phosphomonoesterase Activity in Subalpine Coniferous Forests in China

Studying the altitudinal variation and driving factors of soil acid phosphomonoesterase (ACP) activity in subalpine regions is crucial for understanding nutrient cycling processes within mountainous ecosystems. This study focused on fir (Abies fabri (Mast.) Craib) forests located at three altitudes (2781 m, 3044 m, and 3210 m) on the eastern slope of Mt. Gongga in southwest China. We measured soil ACP activity alongside soil climate, nutrients, and microorganisms at various depths and elevations to investigate how these factors influence ACP activity. The results indicated that in the organic matter horizons (Oe and Oa horizons), ACP activity gradually decreased with elevation. However, the surface mineral horizon (A horizon) did not show a decline in ACP activity with increasing elevation, which could be attributed to significantly lower ACP activity recorded at the 2781 m sample site compared to the 3044 m site. Variance partitioning analysis revealed that among soil climate, nutrients, and microorganisms, soil nutrients had the most substantial impact on ACP activity across all horizons, with a particularly high contribution of 89.4% observed in the A horizon. Random forest model analysis further demonstrated that soil total carbon (TC) played a crucial role in determining ACP activity in the Oe and Oa horizons, with importance values of 8.5% and 7.3%, respectively. Additionally, soil total nitrogen (TN) was identified as the primary factor influencing ACP activity in the A horizon, with an importance value of 12.6%. Furthermore, soil ACP activity was positively regulated by the soil TC:TP and TN:TP ratios, indicating a stoichiometric control of ACP activity in the Abies fabri (Mast.) Craib forests on Mt. Gongga.