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Reclamation variants diversely influenced the physical state of technogenic soil.All soils had favourable values of macroporosity and water available for plants.Application of ...lignite resulted in the lowest air and water permeability.Spontaneous succession contributed to the most preferred soil physical state.
For the assessment of the extent of post-mine land degradation, arranging management practices for sustainable land use, and evaluation of reclamation success research on soil physical properties plays a significant role. The aim of this study was to quantify and interpret the effects of varied agricultural reclamation methods in order to assess which of the treatments yielded higher soil quality with respect to its physical state. Basic physical and chemical parameters (texture, particle and bulk density, total porosity, total organic carbon and pH), soil water characteristic curves, water and air permeability, structure of the soil damaged by mining in the area of internal dumping ground PĿtnów (Central Poland) were therefore measured. The soil samples were taken from the following 5 different variants of over 30-year-long reclamation: black fallow (BF), monoculture of winter wheat (WW), monoculture of winter wheat with a single application in 1992 of lignite dust (WW+L), monoculture of alfalfa with orchard grass in the proportion of 90/10% (A+G), and spontaneous succession (SS). We collected from each treatment: 12 soil cores for soil water and air properties; 6-kg composite bulk samples for basic physical and chemical properties of soil; 1 undisturbed soil block for structure analysis. The reclamation methods applied on the post-mining grounds influenced in a diverse manner the physical state of the 0⿿10cm layer of the developed technogenic soil. Bulk density values generally decreased with the increase of number of factors potentially loosening the soil structure. The studied plots had sandy loam or loamy sand texture which determined their overall air and water properties. The soils were characterized by high macroporosity and favourable content of water available for plants. Less beneficial conditions of the soil were associated with air and water permeability. The present studies indicated that spontaneous succession, with the highest typological diversity of vegetation, contributed to the most preferred soil physical state. Remaining variants of reclamation (including black fallow without vegetation) also provided sufficient air and water relations in the soils. However, it should be emphasised that plants play an important role in TOC accumulation and ensuring relative stability of soil structure. Therefore rehabilitation of post-mining grounds involving vegetation is recommended.
A study was conducted on the physical properties of anthrosols in the Park Ludowy in Lublin. Soil samples for analyses were taken from five pedons, from layers of 0-25, 25-50 and 50-75 cm, into ...cylinders with volume of 100 cm3. Determinations included the bulk density of the soils, particle density, and water capacities at states of high and low water potential. Calculations of total porosity, retention of productive water and water usable for plants, as well as of air capacities at various states of water potential were performed. The physical status of the soils in the Park, formed as an effect of intensive anthropogenic activity, and especially of the introduction of large amounts of foreign material – sugar beet flume mud and loess, should be assessed as very good. The soils were most often characterised by very low bulk density, very high total porosity, full water capacity and field water capacity, very high and high retention of water usable for plants and productive water, and by diversified field air capacity – from low to excessive.
Soils are three-phase systems which undergo changes as soon as the external stresses exceed the internal soil strength, defined by the precompression stress value. The three-dimensional stress ...propagation induces corresponding volumetric soil strain. Soil compaction can result either in a higher bulk density or, when soil loading is attended with retarded water fluxes and high dynamic forces, in a completely homogenised soil characterised by a lower bulk density and a predominance of fine pores. While in natural soils the structure can be described as macroscopically homogeneous, less careful mechanical treatment or reduced addition of organic substances results in less favourable types of soil aggregates. As a result of applied external stresses, physical and chemical processes, such as mass flow and diffusion of water, ions and gases, are at least retarded or even completely altered. Both increased bulk density and homogenisation cause decreased aeration and increased penetration resistance, which results in impeded root development. Reduced water permeability may result in soil erosion, with serious negative effects on the environment. Compacted soil may also contribute to global atmospheric warming due to increased emission of CO2, CH4 and N2O from such soils. Anthropogenic changes in soil structure and soil functions remain constant for extended periods of time and efforts to restore deteriorated soil structure very often fail because of excessive loosening and homogenisation, cultivation of too wet soil or, afterwards, ill-adapted soil management practices, resulting in even worse soil properties. The present paper gives a summary of relevant work performed by the authors.
The paper aimed at a description of the direction of pore cross-sections in soil lessivé after different treatments during onion cultivation in the growing season and in changeable weather ...conditions. The measurements were taken on the basis of opaque soil blocks using computer assisted image analysis. For the statistical evaluation of the obtained results the statistics of two-dimensional vectorial data (circular statistics) was used. In order to compare soil states the Pearson compatibility test 2 was carried out. The obtained results showed that the applied methods of the vectorial data statistics allowed defining the distribution type of pore cross-sections considering their direction. The taken measurements proved that the applied cultivation treatments led to the soil material homogenisation, which was supported by a generally random pore crosssections orientation. The tested soil in most cases showed an isotropic pore distribution. The observed anisotropy resulted mainly from the compaction and intensive or long-lasting rainfall.
A morphometrical analysis was made of soil lessivé surface layer (0–8 cm) after different cultivation treatments and in changeable weather conditions. The basic parameters were discussed ...(macroporosity, i.e. the relative area of pore cross-sections, quantity, mean pore crosssection size characteristic of macropores sized above 42 μm). It was found out that macroporosity is the factor which can best describe changes in the soil structure caused by different external conditions. The other parameters allow for a deeper analysis of soil structure changeability. The structure of the surface layer of the tested soil lessivé developed from silt showed low stability and high susceptibility to compaction by rain.
The present paper aimed at a definition of the pore cross-sections elongation index in soil lessivé (0–8 cm layer) under onion field after different cultivation treatments and in changeable weather ...conditions. The measurements were taken using binary images of opaque soil blocks surfaces sized 75.0 mm × 65.0 mm. Considering difficulty in shape classification of smaller pores for the shape analysis the pores sections with the surfaces of at least 100 pix2 were chosen, which corresponds to 0.179 mm2. The following groups of pore cross-sections were defined according to elongation index: circular 0–0.1, elliptical 0.11–0.5 and elongated > 0.51. It was stated that elongated pores dominated in each tested state of soil, regardless of differentiation of external factors. Circular pores had a little percentage in total numbers of pores. The lowest values of numbers of all pores were observed in soil samples after passage of tractor during fertilization and a month after tractor pressure and onion removal.
The paper aimed at a description of the direction of pore cross-sections in soil lessivé after different treatments during onion cultivation in the growing season and in changeable weather ...conditions. The measurements were taken on the basis of opaque soil blocks using computer assisted image analysis. For the statistical evaluation of the results the statistics of two-dimensional vectorial data (circular statistics) was used. In order to compare soil states the Pearson compatibility test χ2 was carried out. The results showed that the applied methods of the vectorial data statistics made it possible to define the distribution type of pore cross-sections considering their direction. The measurements proved that the applied cultivation treatments led to the soil material homogenisation, which was supported by a generally random pore cross-sections’ orientation. The tested soil in most cases showed an isotropic pore distribution. The observed anisotropy resulted mainly from the compaction and intensive or long-lasting rainfall.
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