Search results for " compaction"
showing 10 items of 36 documents
Use of BEST Procedure to Assess Soil Physical Quality in the Baratz Lake Catchment (Sardinia, Italy)
2016
Conversion of Mediterranean maquis and/or natural forest into agro-pastoral lands is a cause of soil degradation in many Mediterranean areas. Indicators of soil physical quality (SPQ) quantitatively linked to soil hydraulic properties are a valuable tool to assess the effect of land use changes. In this investigation, the Beerkan Estimation of Soil Transfer parameters (BEST) procedure for soil hydraulic characterization was used to estimate SPQ indicators. Four areas of the Baratz Lake watershed, Sardinia, Italy, characterized by both typical natural vegetation (holm oak [ Quercus ilex L.] forest and high maquis) and degraded vegetation (grassland established after fire or clearing of the m…
Unveiled the Source of the Structural Instability of HKUST Powders upon Mechanical Compaction: Definition of a Fully Preserving Tableting Method
2019
Metal–organic frameworks (MOFs) are getting closer to finally being used in commercial applications. In order to maximize their packing density, mechanical strength, stability in reactive environments, and many other properties, the compaction of MOF powders is a fundamental step for the application field of research of these extraordinary materials. In particular, HKUST-1 is among the most promising and studied MOF. Contrary to what reported so far in the literature, here we prove that the tableting of HKUST-1 powders without any damage of the lattice is possible and easy to get. For the first time, this kind of investigation has been performed exploiting its peculiar magnetic properties w…
Morphological characterisation of soil structure in tilled fields: from a diagnosis method to the modelling of structural changes over time
2004
Characterisation of soit structure within the tilled layer of cultivated fields is crucial because the importance of this soil characteristic on the biological, chemical and physical properties of the soil and its repercussions on water cycle, root growth and functioning. We present in this paper a method for field characterisation of soil structure. This method, practised since the 1970s, was designed for field diagnosis of the effects of cropping systems on soil structure. It is based on a stratification of the observation face of a pit dug perpendicular to the direction of tillage and traffic: spatial compartments are distinguished, according to the nature of the mechanical stresses they…
Strategies to Mitigate the Effects of Soil Physical Disturbances Caused by Forest Machinery: a Comprehensive Review
2022
Abstract Purpose of Review Ground-based mechanized forest operations can cause severe soil disturbances that are often long lasting and detrimental to the health of forested ecosystems. To reduce these soil disturbances, focus is being increasingly directed at identifying and using appropriate mitigation techniques. This systematic review considered 104 scientific articles and reported the main findings according to four core themes: terrain-related factors, operational planning, machine modifications, and types of amendments used to mitigate machine-induced soil impacts. Recent Findings For terrain-related factors, most severe disturbances occur on machine operating trails exceeding 20% sl…
Impacts of wood extraction on soil: assessing rutting and soil compaction caused by skidding and forwarding by means of traditional and innovative me…
2021
AbstractIntensive forestry operations may cause soil compaction, plastic soil disturbances and rutting, which are responsible for undesirable effects on soils, vegetation and water bodies. Despite the numerous studies aimed to identify the main factors affecting soil damages, it still remains unclear whether wood extraction methods and driving direction (uphill or downhill) may affect the impacts of forest machines. This research analyses soil compaction and soil penetration resistance as well as rutting from forwarding and skidding using the same farm tractor in up- and downhill wood extraction. Rutting was estimated by 3D soil reconstruction derived by portable laser scanning (PLS) and cl…
A system for the real-time geo-referenced measurement of soil parameters
2011
The aim of this research is to develop a system for accurately measuring in real-time, collecting and processing a high amount of geo-referenced data of soil physical-mechanical parameters, e.g. cone penetrometer resistance, index of soil compaction, and draft force. The system for measuring the soil cone penetrometer resistance is comprised of a load cell, connected to a rod, ending with a cone, and is mounted on a frame, fixed to the front part of a tractor. The system for measuring the draft force required to till the soil is comprised of a load cell, mounted on the hitch hook of a tool carrier, towed by the tractor. Moreover, in order to test the usefulness of the system with different …
Mapping soil compaction measuring cone penetrometer resistance
2003
The quickest way for monitoring soil compaction differences in a field is measuring cone penetrometer resistance. Soil compaction can be significantly spatially variable, depending on the amount and distribution of the traffic of agricultural machines in the field. Therefore, it could be useful to measure soil compaction on a localised basis, in order to produce maps of the damages caused by the traffic of agricultural machines and/or the action of tillage implements. Aim of this paper is to present a system developed by the Department I.T.A.F. for the geo-referenced measurement of cone penetrometer resistance and for mapping soil compaction. This system was built fitting a minitransporter …
Systems for evaluating the correlation between soil cone penetrometer resistance and shear strength
2008
The aim of this research is to study possible correlations between soil compaction (and related soil cone penetrometer resistance measurements) and shear strength normal to the field plane, required to cut the soil with a subsoiler. A measurement system for sensing the soil cone penetrometer resistance was built mounting, on a frame fixed to the front part of a tractor, a rod and a penetration cone with a load cell. A load cell, mounted on the tractor drawbar, pulling a subsoiler, allowed to measure the shear strength normal to the field plane, required to cut the soil. Both load cells were connected, through a display, to a portable computer, where a software was used for acquiring the dat…
Isolated non-compaction, stroke and trabecular meshwork fibrosis
2009
Left ventricular non compaction: epidemiology, clinical findings, diagnosis and therapy
2014
Abstract Left ventricular non compaction (LVNC) is a cardiomyopathy due to an arrest of the normal development of myocardium which determines the persistence of foetal myocardium in post--natal life in at least 2/3 of the wall (criterion known as non compacted/ compacted ratio greater than 2). Although in absence of a confirmed prevalence of LVNC, reviewing literature shows an increasing number of reports over the years, though diagnosed cases represent just the tip of a realistically far wider phenomenon. Clinical manifestations are variable, ranging from the absence of any symptom to congestive heart failure, arrhythmias and systemic thromboembolism. Echocardiography is the gold standard …