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soilsampling, etc ; analytical methods; metaldehyde; methanol; soil types; solvents; Show all 6 Subjects
Abstract:
... Previously published methods for the analysis of metaldehyde were adapted for its reliable quantification in soil extracts. Varied methanol-water extraction solvents were trialed, but the use of pure methanol proved to be the most reliable approach for the scaled down methodology. Analysis of metaldehyde was done using LC-MS. Initially the method had problems with matrix suppression of the signal. ...
soilsampling, etc ; Prosopis juliflora; buried seeds; density; depth; grasslands; rangelands; soil depth; Ethiopia; Show all 9 Subjects
Abstract:
... •We analyzed the composition and spatial variations of soil seed banks of plant species and densities of soil seed banks in Prosopis juliflora invaded and noninvaded grasslands.•Soil samples were collected from soil layers of 0 to 3, 3 to 6, and 6 to 9 cm.•The highest density of 1,037 ± 633 seedlings/m² was recovered from a soil depth of 3 to 6 cm. But, the lowest density of 461 ± 315 seedlings/m² ...
soilsampling, etc ; Globodera pallida; cyst nematodes; detection; extraction; hosts; paper; pathotypes; potatoes; soil; taxonomy; Show all 11 Subjects
Abstract:
... The scope of this paper is limited to the taxonomy, detection, and reliable morphological and molecular identification of the potato cyst nematodes (PCN) Globodera pallida and G. rostochiensis. It describes the nomenclature, hosts, life cycle, pathotypes, and symptoms of the two species. It also provides detailed instructions for soil sampling and extraction of cysts from soil. The primary focus o ...
soilsampling, etc ; ecosystems; pedodiversity; reading; sampling; soil bacteria; soil composition; soil fungi; soil types; Show all 9 Subjects
Abstract:
... The diversity and composition of soil microorganisms needs to be understood as they influence ecosystem processes. MinION is a relatively recent next-generation sequencer, which provides the advantage of sequencing long reads. In this study, two types of soil were prepared experimentally to investigate the possibility of simultaneously analyzing multiple environmental samples using MinION. The Min ...
Wenqi Luo; Runxuan Lan; Dongxia Chen; Bingwei Zhang; Nianxun Xi; Yuanzhi Li; Suqing Fang; Oscar J. Valverde‐Barrantes; David M. Eissenstat; Chengjin Chu; Youshi Wang
... Environmental filtering and limiting similarity mechanisms can simultaneously structure community assemblages. However, how they shape the functional and phylogenetic structure of root neighborhoods remains unclear, hindering the understanding of belowground community assembly processes and diversity maintenance. In a 50‐ha plot in a subtropical forest, China, we randomly sampled > 2700 root clust ...
soilsampling, etc ; mercury; permafrost; vegetation types; China; Show all 5 Subjects
Abstract:
... Permafrost on the Qinghai-Tibetan Plateau (QTP) has been degrading in the past decades. While the degradation may mobilize previously protected material from the permafrost profile, little is known about the stocks and stability of mercury (Hg) in the QTP permafrost. Here we measured total soil Hg in 265 samples from 15 permafrost cores ranging from 3 to 18 m depth, and 45 active layer (AL) soil s ...
soilsampling, etc ; aggregate stability; catenas; sieves; sieving; weight; Show all 6 Subjects
Abstract:
... Many different methods have been proposed to determine aggregate stability. In most of these methods, certain aggregate size is used to estimate the aggregate stability of the whole soil. Determination of aggregate stability on a certain aggregate size is insufficient to represent the aggregate stability of the whole soil and the results are strongly dependent on the size chosen. Therefore, the de ...
soilsampling, etc ; administrative management; agricultural land; area; cities; geostatistics; heavy metals; issues and policy; linear models; pollution; research; risk; soil; China; Show all 14 Subjects
Abstract:
... Soil environmental capacity and risk warning are the core contents of soil security research. In this study, geostatistical analysis, a material balance linear model, and an environmental load capacity method were selected to simulate the environmental capacities of eight heavy metals (Hg, As, Cr, Cu, Ni, Pb, Zn and Cd) in the agricultural land of north Zhongshan City. Then, based on the capacity ...
soilsampling, etc ; correlation; dead wood; fire intensity; fulvic acids; humic acids; humin; moieties; nuclear magnetic resonance spectroscopy; soil organic carbon; wildfires; Show all 11 Subjects
Abstract:
... The composition of humic substances and structural diversity of soil organic carbon (SOC) can be affected by wildfire. In this study, soil samples were collected after 1 year of no fire, low intensity of fire (dead trees ≤ 30%), moderate intensity of fire (dead trees 30–70%) and high intensity of fire (dead trees ≥ 70%). The amounts of humic acid (HA), fulvic acid (FA) and humin (Hu) were investig ...
soilsampling, etc ; behavior; coatings; engineering; estimation; grains; interferometers; mechanical properties; paper; particles; sand; soil; surface roughness; technology; thickness; topography; wettability; white light; Show all 18 Subjects
Abstract:
... Soil grains when treated with dimethyldichlorosilane (DMDCS) create a thin soft coating layer. The presence of such a layer changes the grain surface wettability giving desirable hydraulic properties which has great potential in engineering practice. The thickness of such a layer has been identified to be an influencing parameter for the mechanical properties. But its estimation is not straightfor ...
soilsampling, etc ; americium; analytical specificity; plutonium; radioactivity; radionuclides; soil; Show all 7 Subjects
Abstract:
... The methodology for determination of ²⁴¹Pu in soils of the main test sites of the Semipalatinsk Test Site (STS) has been developed. The results of ²⁴¹Am and ²⁴¹Pu activity determination in soil samples sampled at the main testing sites of the STS are presented. ²⁴¹Pu/²⁴¹Am activity ratio is calculated. In most cases, on local sites, ²⁴¹Pu/²⁴¹Am activity ratio is in a rather narrow range, which mak ...
soilsampling, etc ; models; prediction; soil properties; soil surveys; uncertainty; Show all 6 Subjects
Abstract:
... Many predictive soil mapping (PSM) methods encounter two problems. One is how to construct a similarity index that can indicate not only the similarity of an environmental covariate between sites but also the directional difference of the covariate itself between sites and predict the soil property values beyond the range of sample values. Another is how to determine which soil samples should be u ...
soilsampling, etc ; borates; carbon dioxide; chromatography; environment; extraction; helium; humans; mass; mass spectrometry; measurement; mine tailings; reference standards; sampling; separation; separators; uranium; China; Show all 18 Subjects
Abstract:
... ²³⁶U in the environment mainly originates from human nuclear activities. Based on the unique properties of uranium, ²³⁶U can be used as a powerful tracer for investigation of oceanographic and environmental processes. This requires sensitive measuement of ²³⁶U in various environmental samples. Due to the ultra-low radioactive level of ²³⁶U in the environment, its measurement is only possible by ma ...
soilsampling, etc ; DNA; agricultural productivity; corn; fields; functional diversity; grasslands; metagenomics; microbial communities; microbiome; models; physicochemical properties; rhizosphere; soil; species diversity; South Africa; Show all 16 Subjects
Abstract:
... The characterization of microbial functional diversity proffers the opportunity to understand and manipulate them in various agricultural and biotechnological processes. This study analyzed the functional diversity and metabolic potentials of microbial communities in the rhizosphere of a former grassland and an intensively cultivated land using a shotgun metagenomic approach. We assumed that funct ...
soilsampling, etc ; cadmium; cation exchange resins; chromatography; molybdenum; sorption; zirconium; Show all 7 Subjects
Abstract:
... Distribution coefficient (Kd) data provides the analyst with a powerful set of tools for designing elemental chemical separations. While considerable Kd data exists in the literature for traditional anion and cation exchange resins, a comprehensive Kd study for the majority of the periodic table has not been published to date for several newer Eichrom extraction chromatographic resins. Kd values f ...
soilsampling, etc ; Bayesian theory; artificial intelligence; engineering; geology; soil properties; Show all 6 Subjects
Abstract:
... Identification of subsurface stratification and characterization of spatially varying soil properties profiles in multiple soil layers are indispensable in geotechnical site investigation. Subsurface soils are often stratified first through visual inspection of soil samples obtained from boreholes or soil behavior type index from cone penetration tests. Then, the soil property profile within each ...
soilsampling, etc ; Landsat; crystal structure; iron; lakes; models; soil; Iran; Show all 8 Subjects
Abstract:
... Urmia Lake, located in Iran, has a unique pedological feature as fresh soil materials are being exposed as the lake is shrinking. Overuse of its water resources has caused its water level to drop, particularly in the east shore of that lake. This consequence has caused a serious environmental risk, but created a rare opportunity to investigate the spatial distribution of six iron forms and feature ...
... Histosols have a high organic matter content and therefore a high variability of structures and chemical functional groups with adsorptive capacity. This study aimed to select the most appropriate models to describe the sorption phenomena of Cu and Pb in Histosols, identify the types of bonds between these metals and soil samples, and assess the influence of soil attributes and soil humic substanc ...
soilsampling, etc ; DNA; assays; behavior; detection; energy transfer; fluorescence; fluorescent dyes; glutathione; humans; microwave ovens; microwave treatment; quantum dots; reliability; silicon; synthesis; temperature; water; Show all 18 Subjects
Abstract:
... The rapid and sensitive detection of Hg²⁺ is highly required to protect the environmental safety and human healthy. In the present work, a ratiometric fluorescent sensing platform, consisting of silicon quantum dots (SiQDs), Rox-labelled DNA (Rox-DNA), and Exonuclease III (Exo III), is developed for the accurate detection of Hg²⁺. As for fluorescent probe, we report the first use of glutathione as ...
soilsampling, etc ; agriculture; alpine grasslands; alpine meadows; ecological function; ecosystems; environment; grazing; growing season; knowledge; phytomass; sampling; soil; soil-plant interactions; stoichiometry; water erosion; China; Show all 17 Subjects
Abstract:
... Grazing exclusion is one of the most effective practices to recover the degraded alpine grasslands in Tibetan Plateau. In addition, ecological stoichiometry serves as a key regulator of ecosystem function and is also closely related to nutrient process. However, knowledge about the plant-soil interactions of stoichiometry throughout the growing season is still poorly understood. In this study, we ...