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Differences in genomic macrorestriction patterns of arabinose-positive (Burkholderia thailandensis) and arabinose-negative Burkholderia pseudomallei.

We reported previously two biochemically and antigenically distinct biotypes of Burkholderia pseudomallei. These two distinct biotypes could be distinguished by their ability to assimilate L-arabinose. Some B. pseudomallei isolated from soil samples could utilize this substrate (Ara+), whereas the other soil isolates and all clinical isolates could not (Ara-). Only the Ara isolates were virulent in animals and reacted with monoclonal antibody directed at the surface envelope, most likely the exopolysaccharide component. In the present study, pulsed-field gel electrophoresis was employed for ka…

Evaluation of phosphogypsum and pore volume water rates for reclaiming saline-sodic cambisols of Metehara sugar estate, Central Rift Valley of Ethiopia.

Soil salinity and sodicity are among the major challenges threatening agricultural productivity in the Central Rift Valley of Ethiopia. A column experiment was conducted in laboratory on saline-sodic soils of Metehara Sugar Estate to evaluate the effectiveness of phosphogypsum and leaching in reclaiming these soils. The treatments comprised of five rates of phosphogypsum equivalent to 50, 75, 100, 150, and 200% gypsum requirement, 100% gypsum requirement of natural gypsum, and an absolute control with no amendments applied, and five volumes of leaching water. The treatments were arranged in Co…

Adaptation of Rhizosphere Microbial Communities to Continuous Exposure to Multiple Residual Antibiotics in Vegetable Farms.

The constant application of manure-based fertilizers in vegetable farms leads to antibiotic residue accumulation in soils, which has become a major stressor affecting agroecosystem stability. The present study investigated the adaptation profiles of rhizosphere microbial communities in different vegetable farms to multiple residual antibiotics. Multiple antibiotics, including trimethoprim, sulfonamides, quinolones, tetracyclines, macrolides, lincomycins, and chloramphenicols, were detected in the vegetable farms; the dominant antibiotic (trimethoprim) had a maximum concentration of 36.7 ng/g. …

Appraisal of groundwater contamination from surface spills of fluids associated with hydraulic fracturing operations.

Contaminated groundwater is a priority issue on the environmental agendas of developed countries. Therefore, there is an obvious need to develop instruments and decision-making mechanisms that allow the estimation of the risk to human health due to the presence of contaminants in soils and groundwater, in a fast and reliable manner. Thus, this study aims to assess whether the spilling of hydraulic fracturing fluids prior to injection has a potential risk to groundwater quality in the Kern County Sub-basin, California, by identifying the hydrological factors and solute transport characteristics…

Agriculture is a major source of NO x pollution in California.

Nitrogen oxides (NO x = NO + NO2) are a primary component of air pollution-a leading cause of premature death in humans and biodiversity declines worldwide. Although regulatory policies in California have successfully limited transportation sources of NO x pollution, several of the United States' worst-air quality districts remain in rural regions of the state. Site-based findings suggest that NO x emissions from California's agricultural soils could contribute to air quality issues; however, a statewide estimate is hitherto lacking. We show that agricultural soils are a dominant source of NO …

Longitudinal occurrence of methylmercury in terrestrial ecosystems of the Tibetan Plateau.

Methylmercury (MeHg), a neurotoxin, is a global concern because of its potential risk to human and ecological health. Elevated mercury (Hg) concentrations were recently reported in the Tibetan Plateau (TP) due to increasing Hg input from distant regions, yet little is known about MeHg production and distribution in the terrestrial ecosystems of the TP. Here, we report longitudinal occurrence of MeHg and the factors regulating net MeHg production in 23 grassland sites from eastern to western TP. The soil MeHg content varied from 0.002 to 0.058 ng g-1, with different distribution patterns betwee…

Mercury distribution across 14 U.S. forests. Part II: Patterns of methyl mercury concentrations and areal mass of total and methyl mercury.

This study characterized distribution patterns of monomethyl mercury (MeHg) and areal mass of total mercury (THg) and MeHg across U.S. upland forests. MeHg concentrations increased from surface litter (average: 0.14 μg kg(-1)) to intermediate (0.47 μg kg(-1)) and deeper, decomposed litter (1.43 μg kg(-1)). MeHg concentrations were lower in soils (0.10 μg kg(-1) at 0-20 cm depth; 0.06 μg kg(-1) at >20 cm depth). Ratios of MeHg to THg were higher in litter compared to soils. In soils, MeHg concentrations positively correlated with THg across all sites, and MeHg concentrations also increased with…

Phosphorus transformations during decomposition of wetland macrophytes.

The microbially mediated transformation of detrital P entering wetlands has important implications for the cycling and long-term sequestration of P in wetland soils. We investigated changes in P forms in sawgrass (Cladium jamaicense Crantz) and cattail (Typha domingensis Pers.) leaf litter during 15 months of decomposition at two sites of markedly different nutrient status within a hard-water subtropical wetland (Water Conservation Area 2A, Florida). Leaf litter decomposition at the nutrient enriched site resulted in net sequestration of P from the environment in forms characteristic of microb…

Reduction of trichloroethylene and nitrate by zero-valent iron with peat.

The feasibility of using zero-valent iron (ZVI) and peat mixture as in situ barriers for contaminated sediments and groundwater was investigated. Trichloroethylene (TCE) and nitrate (NO(3)(-)), redox sensitive contaminants were reduced by ZVI and peat soil mixture under anaerobic condition. Peat was used to support the sorption of TCE, microbial activity for biodegradation of TCE and denitrification while TCE and nitrate were reduced by ZVI. Decreases in TCE concentrations were mainly due to ZVI, while peat supported denitrifying microbes and further affected the sorption of TCE. Due to the co…

Влияние ПГПР на структуру микробиологической сообщества ризосферы и урожайность солончаковых зерновых культур.

Растворяющиеся в почве бактерии, способствующие росту растений (PGPR), могут защищать растения от почвенных заболеваний и абиотических стрессовых условий. Основная цель данного исследования заключалась в оценке влияния различных PGPR (TF1, TF2, TF3 и TF4) на микробную сообщество ризосферы зерна для корма в солончаково-щелочной поле с использованием высокопроизводительной технологии последовательного секвенирования Illumina MiSeq. Результаты показали, что различные PGPRs значительно увеличили плотность уборки (на 21,31–45,16%), высоту растения (на 9,12–19,98%), диаметр стебля (на 30,07–45,78%)

Совпадение в аннотации оригинала
Plant Growth Promoting Rhizobacteria, PGPR, can protect plants against soil-borne diseases and abiotic stress conditions. The primary objective of this study was to evaluate the effects of different PGPRs (TF1, TF2, TF3, and TF4) on the rhizosphere microbial community of silage maize in a saline-alkaline field via Illumina MiSeq high-throughput sequencing te…

Molecular detection of potentially zoonotic protozoa in the Chandigarh region, India.

CONTEXT: The contamination of soil by pathogenic protozoan parasites from both human and animal feces, is an important factor in the spread of parasitic infections globally. This contamination also serves as a crucial reservoir for zoonotic diseases, facilitating their transmission. In many developing nations, including India, there's limited documentation on the extent of soil contamination, which poses challenges for implementing effective One Health strategies aimed at controlling these infections. AIM: To study the molecular prevalence and distribution pattern of pathogenic protozoa in so…

Vapor-phase biodegradation and natural attenuation of petroleum VOCs in the unsaturated zone: A microcosm study.

Traditional natural attenuation studies focus on aqueous process in the saturated zone while vapor-phase biodegradation and natural attenuat … phatic hydrocarbons and 3 fuel ethers all have relatively low attenuation rates (<0.54 d-1) in live soil and negligible biodegradation contribution. We explored the effects of soil types (black soil, yellow earth, lateritic red earth and quartz sand), soil moisture (2, 5, 10, and 17 wt%) contents and temperatures (4, 15, 25, 35 and 45 °C) on the vapor …

Ecological Determinants of Sporotrichosis Etiological Agents.

Ecological determinants of sporotrichosis etiological agents remain poorly understood. For this reason, we performed explorations using loca … ere included in the analysis where medically relevant species of Sporothrix have been isolated from soil samples, and described a specific geographical location that could be precisely georeferenced. We approximated temperature and humidity from local climate estimates, integrating geospatial data, temperature, and water vapor pressure from regions or …

Reductive dehalogenation of chlorinated benzenes and toluenes under methanogenic conditions.

The anaerobic metabolism of chlorinated benzenes and toluenes was evaluated in soil slurry microcosms under methanogenic conditions. A mixture of hexachlorobenzene, pentachlorobenzene, and 1,2,4-trichlorobenzene (TCB) in soil slurries was biotransformed through sequential reductive dechlorination to chlorobenzene (CB). The metabolic pathway for hexachlorobenzene and pentachlorobenzene decay proceeded via 1,2,3,4-tetrachlorobenzene (TTCB)-->1,2,3-TCB + 1,2,4-TCB-->1,2-dichlorobenzene (DCB) + 1,4-DCB-->CB. In a mineral salts medium, the CB-adapted soil microorganisms dehalogenated individual 1,2…

Seasonal shifts in water-source partitioning and fine-root overlap in a Populus simonii-maize shelterbelt system.

INTRODUCTION: Farmland shelterbelts are critical for agricultural production in arid and semiarid regions, but they may compete with crops for limited soil water. This study aimed to quantify seasonal water-source use, soil moisture dynamics, and fine-root distribution in a Populus simonii-maize shelterbelt system. METHODS: The study was conducted in Zhangbei County, northwestern Hebei Province, China. Three land-use conditions were compared: a pure P. simonii shelterbelt (P), a P. simonii-maize intercropping system (PC), and a maize monoculture reference (C). Synchronous sampling was conduct…

Clipping-and-burning alters carbon and nitrogen cycling through bacterial fixation pathways in the key Chinese karst region.

Clip-and-burn is a forestry and land management technique common in China and other tropical regions worldwide to clear land for agriculture or to manage vegetation. However, the dynamics of carbon and nitrogen in karst regions following clip-and-burn practices remain largely unknown. Here, we evaluate the impact of clip-and-burn management practices on carbon and nitrogen cycling in the Karst region of China. The treatments included high-intensity fire (HIF), low-intensity fire (LIF), clipping and fire (CF), clipping (CP), and control (CK). Soil samples were collected one year after treatment…

RhizoMAP: a comprehensive, nondestructive, and sensitive platform for metabolic imaging of the rhizosphere.

BACKGROUND: Elucidating the intricate structural organization and spatial gradients of biomolecular composition within the rhizosphere is critical to understanding important biogeochemical processes, which include the mechanisms of root-microbe interactions for maintaining sustainable plant ecosystem services. While various analytical methods have been developed to assess the spatial heterogeneity within the rhizosphere, a comprehensive view of the fine distribution of metabolites within the root-soil interface has remained a significant challenge. This is primarily due to the difficulty of ma…

Employment of pqqE gene as molecular marker for the traceability of Gram negative phosphate solubilizing bacteria associated to plants.

Insoluble phosphorous compounds solubilization by soil bacteria is of great relevance since it puts available the phosphorus to be used by plants. The production of organic acids is the main microbiological mechanism by which insoluble inorganic phosphorus compounds are solubilized. In Gram negative bacteria, gluconic acid is synthesized by the activity of the holoenzyme glucose dehydrogenase-pyrroloquinoline quinine named GDH-PQQ. The use of marker genes is a very useful tool to evaluate the persistence of the introduced bacteria and allow to follow-up the effect of biotic and abiotic factors…

A Superior Trifunctional Electrocatalyst of Ni-Mn-Co Sulfide Anchored on Nitrogen-Doped Graphene Derived From Spent Lithium-Ion Batteries.

Alpine ecosystems are experiencing warming, leading to alpine greening-an upward migration and enhanced productivity of vegetation. Although soils represent the largest carbon (C) stocks in these ecosystems, impacts of greening on soil organic carbon (SOC) dynamics remain unknown, especially in the high alpine zone. We measured SOC stocks, quality and radiocarbon (14C) based turnover rates along elevation gradients from (sub)alpine forests to periglacial zones on three bedrock types, representing trajectories of changes in climate and vegetation and weathering regime. Data were linked to SOC s…

Between Mosses and Microbes: Stable Isotopes (15N/14N, 13C/12C) Clarify the Trophic Niches of Oribatid Mites on a High-Arctic Permafrost Archipelago (Svalbard, Norway).

Tundra biomes are strongly affected by globally changing temperatures. Rising temperatures will increase soil biota activity and result in higher CO2 release from tundra soils and 'greening' of this biome, which in turn will affect carbon cycling and soil food webs. It is therefore important to better understand those high-latitude soil food webs in tundra biomes. Here, we investigated adult and juvenile soil living oribatid mites (Acari) in eight different microhabitats (i.e., patches of vegetation from Bistorta vivipara, Carex sp./Luzula sp., Cassiope tetragona, Dryas octopetala, Salix spp. …