River deltas are often considered as hotspots of atmospheric carbon regulation, but few studies have paid attention to the differences between topsoil and subsoil for sequestration. Here physical chemical stabilization mechanisms sources soil organic (OC) accumulation in different layers a major river delta (Yellow delta) were studied by fractionation isotopic analysis. We found that topsoil, c...

Introduction: In the search for life on Mars nearsurface soil environments may be important habitats for life accessible to future missions. Serpentinite rocks have been documented on Mars [1], as well as other clay minerals including smectite and kaolinites [2, 3]. Previous studies of soils formed on serpentinites on Earth have documented the formation of extensive clays, including smectite [4...

Understanding the plant species diversity could be used as an importantindicator applied for the natural areas management. The aim of this study was toinvestigate the relationships between soil characterizes with distribution and diversity ofplant in vegetation types in Karvan district (located in west of Isfahan province). For thispurpose, three vegetation types were selected as follows: Scari...

ABST RACT: Tritium accumulation in clay minerals (kaolinite, montmorillonite, palygorskite) was studied experimentally over a one year contact with tritiated water (initial activity 1.67610 Bq/m) under room conditions, and was compared to theoretical calculations. The amounts of tritium ions in bound water and structural hydroxyls were measured by the activity of water fractions released at cha...

Soil biotic and abiotic factors strongly influence nitrogen (N) availability and increases in nitrification rates associated with the application of manure. In this study, we examine the effects of edaphic properties and a dairy (Bos taurus) slurry amendment on N availability, nitrification rates and nitrifier communities. Soils of variable texture and clay mineralogy were collected from six US...

Weathering products of two fragments of Dronino iron ungrouped meteorite found in the wet and drier clay sand were studied using X-ray diffraction and Mössbauer spectroscopy with a high velocity resolution. The products of metal oxidation in the internal and external surface layers were different for both fragments. The weathering products in fragment found in the wet clay sand contain magnetit...

Both climate and plant species are hypothesized to influence soil organic carbon (SOC) quality, but accurate prediction of how SOC process rates respond to global change will require an improved understanding of how SOC quality varies with mean annual temperature (MAT) and forest type. We investigated SOC quality in paired hardwood and pine stands growing in coarse textured soils located along ...

A controlled greenhouse experiment was conducted to study the fraction, uptake and fixation of phosphorus (P) and potassium (K) in three soils with contrasting characteristics. The experiment was carried out in two phases, viz., sorghum-Sudangrass depletion and test crop experiment with maize with three levels of fertility status (depleted, original and fertilized with 40 mg kg-1 P and K) and t...

The similarities and differences in the structures of the nifH gene pools of six different soils (Montrond, LCSA-p, Vernon, Dombes, LCSA-c, and Thysse Kaymor) and five soil fractions extracted from LCSA-c were studied. Bacterial DNA was directly extracted from the soils, and a region of the nifH gene was amplified by PCR and analyzed by restriction. Soils were selected on the basis of differenc...

Both climate and plant species are hypothesized to influence soil organic carbon (SOC) quality, but accurate prediction of how SOC process rates respond to global change will require an improved understanding of how SOC quality varies with mean annual temperature (MAT) and forest type. We investigated SOC quality in paired hardwood and pine stands growing in coarse textured soils located along ...