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Fungal communities colonizing Ophiocordyceps spp. plays a crucial ecological role in their natural habitat, contributing to infect the host larvae, and influencing their occurrence. Although associated fungi with the newly described Ophiocordyceps indica, from the Indian Western Himalaya remains unclear. Therefore, we untangled the culturable fungal communities associated with O. indica and soil adhered to it, collected from low‐height areas of Himachal Pradesh, India. The study resulted in the identification of 111 fungal isolates representing 17 families, with maximum fungal isolates (36.03%) within Cordycipitaceae. Interestingly, a total of 24 genera were found associated with O. indica and adhered soil, of which 12 were common, 8 were exclusive to O. indica and 4 were only limited to soil. Additionally, the influence of soil physicochemical parameters on fungal diversity indices revealed a positive correlation with humidity and available nitrogen and a negative correlation with pH and available phosphorus. These findings provide insights into the culturable fungal diversity of O. indica and the soil adhering to it, thus can contribute to the understanding of host‐microbial interactions. Furthermore, these associations can be explored as a source of bioactive metabolites to combat the unending industrial demands. [ABSTRACT FROM AUTHOR]

The combined application of geotechnical and geophysical methods provides an effective means of subsurface exploration. The insufficient correlation between geotechnical and geophysical methods prevents the conversion of geophysical data to geotechnical information and vice versa. In the present study, a correlation has been proposed between the geotechnical and geoelectrical properties of two soil deposits in India. Eleven boreholes along with a Standard Penetration Test (SPT) and different laboratory tests have been conducted to obtain the different engineering and physical properties of the soil layers. Twelve Electrical Resistivity Tomography (ERT) profiles have also been conducted to obtain the resistivity profile of the subsurface layers. The variation of the resistivity of the soil layers is analyzed and explained. Results show a strong linear correlation between resistivity and SPT blow counts (N′) of the soil layer for one site while a weak correlation for another site. A strong linear correlation between transverse resistivity (T) and N′ values has been observed for both sites. A comparison with the other existing correlation between resistivity/transverse resistivity and N′-values has also been presented. The range of resistivity values and engineering properties of soil layers are mentioned. The study is useful for the development of similar correlations and provides an approximate estimation of different geotechnical parameters for infrastructure design. • The study investigates the site-specific correlation between geotechnical and geoelectrical properties of two sites in India. • The subsurface exploration of the site has been conducted through SPT N and resistivity measurement. • Correlation between N and resistivity has been developed and presented. • Correlation between N and transverse resistivity has been developed and presented. • A comparison between the previous and present study has been made. [ABSTRACT FROM AUTHOR]

Soil cation exchange capacity (CEC) is an important measure of soil fertility, owing to the large number of plant essential nutrients which are taken up by plants as cations. However, current methods for evaluating soil CEC are arduous and require analysis in a laboratory. Portable X-ray fluorescence (PXRF) spectrometry is a proximal sensing technique which provides elemental data in-situ, in seconds. This study examined the potential of using PXRF for soil CEC prediction by evaluating 450 soil samples from California and Nebraska, USA representing a wide variety of soil textures found in active farm fields. Multiple linear regression was applied to a modeling dataset to establish the relationship between lab-determined CEC and PXRF elemental data. A second model also included auxiliary input data (soil clay, pH, organic matter) as potential modeling variables. Both models were shown to perform similarly, with the auxiliary input model providing slightly higher R 2 (0.926 vs. 0.908) and slightly lower RMSEs (2.236 vs. 2.498) compared to pure elemental data models. Independent validation datasets were compelling for both pure elemental models (0.904) and auxiliary input models (0.953). Summarily, PXRF was able to predict soil CEC accurately, thereby minimizing the need for lab-based CEC data for many applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • Short-term reactivity of arsenate [As(V)] in different soil microsites was assessed. • Arsenate binding did not solely depend on Fe and Al (hydr)oxides. • Solids containing Mn, Zn, Ti, and Cu can potentially enhance As(V) retention. • Variations in As(V) retention across soils could not be ascribed to pedogenic effects. • Microscale heterogeneity affects As retention regardless of the pedogenic environment. Determining reaction mechanisms that control the mobility of nutrients and toxic elements in soil matrices is confounded by complex assemblages of minerals, non-crystalline solids, organic matter, and biota. Our objective was to infer the chemical elements and solids that contribute to As binding in matrices of soil samples from different pedogenic environments at the micrometer spatial scale. Arsenic was reacted with and imaged in thin weathering coatings on eight quartz sand grains separated from soils of different drainage classes to vary contents of Fe and Al (hydr)oxides, organic carbon (OC), and other elements. The grains were analyzed using X-ray fluorescence microprobe (µ-XRF) imaging and microscale X-ray absorption near edge structure (μ-XANES) spectroscopy before and after treatment with 0.1 mM As(V) solution. Partial correlation analyses and regression models developed from multi-element µ-XRF signals collected across 100 × 100 µm2 areas of sand-grain coatings inferred augmenting effects of Fe, Zn, Ti, Mn, or Cu on As retention. Significant partial correlations (r′ > 0.11) between Fe and Al from time-of-flight secondary ion mass spectrometry (TOF-SIMS) analysis of most samples suggested that Fe and Al (hydr)oxides were partially co-localized at the microscale. Linear combination fitting (LCF) results for As K-edge μ-XANES spectra collected across grain coatings typically included >80% of As(V) adsorbed on goethite, along with varying proportions of standards of As(V) adsorbed on boehmite, As(V) or As(III) bound to Fe(III)-treated peat, and dimethylarsinic acid. Complementary fits for Fe K-edge μ-XANES spectra included ≥50% of the Fe(III)-treated peat standard for all samples, along with goethite. Our collective results inferred a dominance of Fe and possibly Al (hydr)oxides in controlling As immobilization, with variable contributions from Zn, Ti, Cu, or Mn, both across the coating of a single sand grain and between grains from soils developed under different pedogenic environments. Overall, these results highlight the extreme heterogeneity of soils on the microscale and have implications on soil management for mitigating the adverse environmental impacts of As. [ABSTRACT FROM AUTHOR]