Published in Scientific Papers. Series E. Land Reclamation, Earth Observation & Surveying, Environmental Engineering, Vol. IV
Written by Florian STATESCU, Dorin COTIUSCA-ZAUCA, Vasile Lucian PAVEL, Paula COJOCARU, Maria PASTIA
The protection of soils and thus maintaining the ability to perform their ecological function requires careful analysis ofthe soils properties. The diversification of protection and de-pollution techniques of the soil determines the developmentof investigation techniques, both of the composition and of the soil characteristics.In this regard, experimentsperformed in the Laboratory of Soil Science from the Technical University "Gheorghe Asachi" University, and otherinstitutions with which the University has collaborative relationships represents an important contribution to thedevelopment of research methodology of soil for various purposes. Some of the most significant results were obtained insoil physics and refers to: the use of infrared spectrometry in research of soil matrix composition, the study of soilporosity by electron microscopy and medical imaging technique, the experimental determination of hydraulicconductivity of soil and the use of mathematical models in research on aero-hydric soil regime.Themineralogicalcomposition of the clay in soil was studied using IR spectra obtained with a Shimadzu spectrophotometer Iraffinity-1.Colloidal inorganic matrix or clay, as it is commonly called, has a number of properties which are a result of thecharacteristics of its components. The quality of the clay can be established by identification of these components andtheir proportions. Clay minerals identified in studied clay soils are: illite, smectite (montmorillonite), kaolinite andchlorite. In addition, spectrometry revealed the presence of vermiculite elements or poorly expressed interstratifications.QUANTA electron microscope 3D Dual Beam 200, used in the study of the soil porosity, is a combinationof two systems:- SEM is an electron microscope that produces enlarged images of a variety of samples performing amagnification of over 100,000x at a high resolution digital format.- FIB is an ion beam system that provides highresolution images.In the field of soil science, for research on porous environment, axial tomography using X-ray (X-raycomputer tomography - CT) or Gamma is a highly effective and innovative method for investigating soil structure,spatial distribution of porosity and ground water content.Experimental determination of the soil hydraulic conductivitywas made on a modern complex installation, having the possibility of recording data and their automaticprocessing.Land MOHID software was used to simulate water flow through porous media (soil). It solves the Richardsequation for saturated and unsaturated porous media. Currently, soil hydraulic properties are described by using theVan Genuchten equation. However, the model is prepared, where appropriate, to include any model which describeswater content and the hydrostatic pressure or the relationship between the conductivity and hydrostatic pressure,respectively. The simulation results showed that the MOHID Land computer program, with adjustments made byPorous Media Module Properties, PREEQC and Sediment Quality, is a pertinent tool for analysing issues like: soilwater dynamics, transport of solutions and transformations undergone by the different substances and somecomponents of the air from the soil.For the soil water dynamics simulation using Land MOHID software, it is necessarythat the input data such as rainfall, irrigation and soil characteristics (hydraulic parameters) to be representative in thestudied area and obtained as result of high rank analysis and quality studies. The conclusions emphasize theimportance of results and contributions to the development of knowledge, which are appreciated as result of a coherentand relevant analysis of the scientific literature.
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