soil from the central Nile Delta, and a clay soil from the western region of the Nile Delta. Pertinent physical and chemical soil properties of the two soils were determined. Discussion of the results (mechanical resistance, hydraulic resistance, change
In this study, changes and relationships of both resistances under sprinkle irrigation (or rainfall) and sprinkle followed by flooding, were examined. Two typical agricultural soils in the Egyptian Delta were used for the experiment : a silt-loam
Structural stabilities of some soils were measured on aggregates sieved 2-1mm diameter. A hybrid index of structural stability is proposed to predict signs of likely structural instabilities of soils when subjected to mechanical and osmotic stresses
Mechanical consolidation in volcanic ash soils in Impact of water and external forces on soil structure. Selected papers of the 1st Workshop on soilphysics and soilmechanics, Hannover 1986.
The objective of this paper is to evaluate the physical changes and mechanical parameters in soils from southern Chile (39-41o s. l.) with a wide range of andic character reflected by different carbon and clay content on the base consolidation tests
, and to analyse the parameters in soils with different intensity of land use.
Application of SoilMechanical Response Units (SMRU) in regional landslide hazard assessment
Cenozoic ; Escarpment ; Geographical information system ; Geomorphometry ; Germany ; Hessen ; Landslide ; Lithology ; Mass movement ; Model ; Natural hazards ; Soilmechanics
This study defines and describes SoilMechanical Response Units (SMRU) for use as input parameters and is thus a combined heuristic and soilmechanical approach to landslide hazard assessment. SMRU's were delimited using a Geographical Information
for the soil which was most susceptible to wetting. Indices of relative mechanical stability have been developed which will assist interpretation.
In this study, erosion and sediment characteristics were measured in simulated rainfall experiments for 3 forest soils of contrasting physical properties. 4 erosion treatments combined varying slope and kinetic energy of rainfall to provide 3
effective levels of energy from rain and runoff. A comparison of soil loss and size-distribution (quantified as Mean Weight Diameter, MWD) of the uneroded soils with size-distribution of sediment indicated soil loss to be greatest and sediment finest
Soil aggregation in arid and semi-arid environments
Aggregate ; Agropedology ; Land use ; Methodology ; Soil ; Soil properties ; United States of America
be easily constructed from locally purchased materials. The manual versus the mechanized wet-sieving technique was compared, and the proposed method is demonstrated on different soil types and land uses for soil quality assessments.
The most common method for measuring aggregate stability in water is wet sieving. The objective of this paper is to present a low cost modified version of this method that does not require the use of a mechanized wet-sieving machine and can
Based on the data of the electron scanning of loess microstructure and the soil tests, the paper presents a hypothesis : the collapsing deformation of loess comes from the damage of the microstructure stability. In accordance
Presents the results of laboratory experiments on hydrophobic and wettable soils to investigate the differences in 1) the amounts of soil material detached by simulated rainfall, and 2) the splash detachment mechanisms by comparing splash ejection
Quantifying the mechanical and hydrologic effects of riparian vegetation on streambank stability
Bank erosion ; Erosion control ; Geotechnics ; Mississippi ; Modelling ; Riparian vegetation ; Soil properties ; Stream ; United States of America
This paper reports a field monitoring and computer-modelling investigation that has been carried out in northern Mississippi to quantify the separate and combined hydrologic and mechanical effects of 3 different vegetation covers (mature trees
Runoff and interrill erosion on sandy soils under cultivation in the western Paris Basin : mechanisms and an attempt at measurement
Bassin parisien ; Cultivated land ; Experiment plot ; France ; Land use ; Rainfall simulation ; Rill wash ; Sedimentology ; Soil erosion ; Splash ; Water erosion ; Watershed
Measurements made on different scales, such as rainfall simulations on 1 m2 and 20 m2 experimental plots and water sampling at the outlet of a watershed, enable the analysis of the mechanisms of pluvial erosion and therefore the importance
of runoffs and soil losses in the hilly and sandy parts of the western Paris Basin. Sedimentological analyses are used to explain the change in runoff coefficients and the variation in mobility of the soil particles according to the different soil types
. The AA. then draw conclusions about runoff and interrill erosion on sandy soils.
Alpes de Haute-Provence ; Alps (The) ; France ; Landslide ; Mass movement ; Methodology ; Natural hazards ; Slope ; Soilmechanics
This study focuses on the assessment of the hazard on local and regional scale of a particular type of mass movement, the landslide. The general aim is to extend the probabilistic soilmechanical approach to landslide hazard analysis. The study area
Temperature and moisture trends in non-sorted earth hummocks and stripes on the Old Man Range, New Zealand : implications for mechanisms of maintenance
Freezing ; New Zealand ; Patterned ground ; Periglacial features ; Soil moisture ; Soil temperature ; South Island ; Temperature gradient
The mechanisms of maintenance of earth hummocks and non-sorted stripes in seasonally frozen ground on the Old Man Range, Otago, were investigated. An array of thermistors at each of 2 sites was used to monitor soil temperature gradients during 3
winters, and replicate soil cores were taken in autumn and winter to determine soil moisture gradients. Freezing occurred mainly in the crests and sides (heavily influenced by aspect), and patterns of freezing showed strong interannual consistency. Soil
In this paper, soil erodibility in water and wind erosion research is discussed on analyzing the concept and mechanism of soil erodibility, methods to measure and calculate soil erodibility. At the same time, the defect and researching orientations
of soil erodibility in water and wind erosion are also discussed.
Hydrology ; Mass movement ; Pedogenesis ; Slope ; Slope dynamics ; Soil properties
response. This research represented the first attempt to link the mechanical properties of developing regolith with slope angle changes over geological time, and is a significant milestone in the integration of engineering soilmechanical principles
This article considers the role of progressive changes which occur within individual horizons to produce an increasingly differentiated soil cover. The increasing internal differentiation of the soil cover has complex effects on its hydrological
This study demonstrates the contrasting mechanisms of landslides in adjoining hills with permeable (sandstone) and impermeable (mudstone) bedrock in the Boso Peninsula. The characteristics of slope hydrology were inferred from pressure-head
monitoring and rainfall-runoff observations. An analysis of slope stability provided critical conditions for several previously occurring landslides. This study also postulates that the difference in the landslide mechanisms account for varying hill
Responses of soil nutrient to driving mechanism in Taihu Lake basin in last 20 years
Agricultural practice ; China ; Human impact ; Sichuan ; Soil ; Soil improvement ; Soil pollution ; Soil properties ; Sustainable development ; Watershed
The aim of this study is to understand the changing law of soil nutrient quality in Taihu Lake basin in the recent 20 years, and reveal the relationship between soil nutrient changes and human driving forces at a regional level over long time
. Hopefully, this approach will provide a tool to indicate soil nutrient changes, optimize efficiency of chemical fertilizer applied, lessen environmental pollution, and develop sustainable land management.
Soil slips on weathering-limited slopes underlain by coarse-grained granite or fine-grained gneiss near Seoul, Republic of Korea
Gneiss ; Granite ; Landslide ; Recurrence interval ; Rock mechanics ; Seoul ; Shear stress ; Slope ; Slope gradient ; South Korea ; Weathering
The chemical, mineral, physical, and mechanical properties of 2 soil layers on soil-slip scars in slopes underlain by coarse-grained granite and fine-grained granitic gneiss near Seoul, were examined. The aim is to study the effects of the mineral
grain size of the bedrock on the soil layer structure and the return period of shallow soil slips. In the granite soil layers, the sliding plane corresponds to the minimum shearing resistance, whereas in the gneiss soil layers, the shearing resistance
increases gradually with soil depth, and the sliding plane is formed when the weathering front is located deeper.