Temporal Stability of Apparent Soil Electrical Conductivity Measured by Electromagnetic Induction Techniques

Assessing and managing the spatial variability of hydropedological properties are important in environmental,agricultural,and geological sciences.The spatial variability of soil apparent electrical conductivity(ECa) measured by electromagnetic induction(EMI) techniques has been widely used to infer the spatial variability of hydrological and pedological properties.In this study,temporal stability analysis was conducted for measuring repeatedly soil ECa in an agricultural landscape in 2008.Such temporal stability was statistically compared with the soil moisture,terrain indices(slope,topographic wetness index(TWI),and profile curvature),and soil properties(particle size distribution,depth to bedrock,Mn mottle content,and soil type).Locations with great and temporally unstable soil ECa were also associated with great and unstable soil moisture,respectively.Soil ECa were greater and more unstable in the areas with great TWI(TWI > 8),gentle and concave slope(slope < 3%; profile curvature > 0.2).Soil ECa exponentially increased with depth to bedrock,and soil profile silt and Mn mottle contents(R2= 0.57),quadratically(R2 = 0.47),and linearly(R 2 = 0.47),respectively.Soil ECa was greater and more unstable in Gleysol and Nitosol soils,which were distributed in areas with low elevation(< 380 m),thick soil solum(> 3 m),and fluctuated water table(shallow in winter and spring but deep in summer and fall).In contrast,Acrisol,Luvisol,and Cambisol soils,which are distributed in the upper slope areas,had lower and more stable soil ECa.Through these observations,we concluded that the temporal stability of soil ECa can be used to interpret the spatial and temporal variability of these hydropedological properties.

Summary of Experience from the Long-Term Pedological Research on the Banks and Slopes of Lake Most

This paper briefly assesses the conclusions from the long-term research of soil properties of the banks and shore of Lake Most. This paper mainly deals with the long-term development of the soil parameters of the anthropogenic soil profile and, to a lesser extent, the assessment of soil habitats with a typical flora. The experience gained will aid in the planning of further hydrological reclamation.

Soils of Fildes Peninsula,King George Island,the maritime Antarctic:Part^->.Formation processesand pedogenetic particu-larities

Based on the data obtained from tens of the investigated soil profiles scattered over the Fildes Peninsula, King George Island, the maritime Antarctic, the soil forming processes were discussed. It was concluded that on the weathering crusts resulted from various physical courses, the strong freeze thaw action within regolith, significant organic matter accumulation, evident leaching and illuviation, as well as initial argillification dominated the formation and development of the soils on the Fildes Peninsula. Furthermore, this study indicated that the juvenility of genesis, poor profile expression, variation in column thickness, etc. characterized the pedogenetic features of the soils of the Fildes Peninsula.

Soil Mapping of a Small Watershed in a Brazilian Savanna Biome: A Semi-Automatic Approach

The objective of this work is to propose a semi-automatic methodology for the creation of a semidetailed to detailed watershed’s soil map. This methodological proposal is based on the traditional method (field work and photo interpretation) and on morphometric variables analysis, using data originated from the Digital Elevation Model (DEM) of the Shuttle Radar Topography Mission (SRTM) program. The steps taken through this methodological proposal were the identification of the hydromorphic areas boundaries through interpretation of aerial orthophotographs;the compartmentalization of the relief through color composition techniques using the morphometric variables—slope, altimetry and horizontal curvature;the development of a pedological database based on data gathered in the field;the elaboration of a preliminary soil map based on the compartmentalized relief and on the dataset of the soils sampled in the field;the elaboration and adjustment of the final soil map according to the interpretation of aerial photographs and also the physical and chemical analyses of the soils. This semi-automatic methodology demonstrated improved efficiency in defining the soil units, reducing operation time and subjectivity of the process, thereby contributing to the systematization of soil mapping at watershed level in scale 1:50,000, as well as, promoting better knowledge between the relation of the geomorphic and soil variables in the Brazilian Savanna Cerrado.

Clay Sorbents in the Area of the Most and Sokolov Basins as a Possible Use in Agriculture Reclamations

This paper is devoted to the possibilities of the reclamation use of claystone sorbents of the Most and Sokolov basins. The properties of phytotoxic areas suitable for the application of sorbents, the locality, and parameters of the main clay sorbents of both brown coal basins are briefly summarized in the paper. Clay sorbents are suitable for the reclamation of phytotoxic surfaces contaminated by coal. This paper provides a brief evaluation of the properties of the claystone sorbents of the North Bohemian and Sokolov basins. In the region of the North Bohemian brown coal basin, potential sorbents can be used for the reclamation works.

Micromorphological description of vernacular cob process and comparison with rammed earth

Past builders have developed very low-embodied energy construction techniques optimizing the use of local building materials.These techniques are a source of inspiration for modern sustainable building.Unfortunately,this know-how was orally transmitted and was lost as earth construction fell into disuse during the 20th century in European countries.The absence of written documents makes necessary to use an archaeological approach in order to rediscover these construction strategies.Micromorphological analysis of thin sections collacted in earth building walls was used for the first time to describe cob construction technique and highlighted several typical pedofeatures allowing to clearly identifying this process.Finally,a first comparison of the cob and rammed earth micromorphological features permitted to identify two key factors to distinguish these two techniques,the manufacturing state(solid or plastic)and the organization of the material in the wall.