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  • Colloidal stability in some tropical soils of southeastern Nigeria as affected by iron and aluminium oxides
  • Aggregate ; Geochemistry ; Microstructure ; Nigeria ; Soil ; Soil properties ; Structural stability ; Tropical zone ; Weathering
  • The aims of this study are to : identify the rate of colloidal stability of the soils using indices; and identify the different forms of Fe and Al oxides in the soils and relate them to the stability of the colloids and microaggregate indices. Ten
  • soils from southeastern Nigeria on 2 major geological formations were sampled. Discussion of the results.
  • 2009
  • [b1] Dep. of Soil Science, Univ., Nsukka, Nigeria
  • The depiction of soil profiles since the late 1700s
  • Catena ; Cross section ; Eighteenth Century ; Graphics ; History of sciences ; Nineteenth Century ; Photography ; Soil ; Soil properties ; Soil science ; Twentieth Century
  • Catena ; Histoire des sciences ; Photographie ; Profil transversal ; Propriétés du sol ; Pédologie ; Représentation graphique ; Siècle 18 ; Siècle 19 ; Siècle 20 ; Sol
  • This paper traces the depiction of soil profiles in the scientific literature from the late 1700. The first soil profile depictions were simple diagrams illustrating different layers and soil processes. Photographs started to appear in textbooks
  • at the end of the nineteenth century. In the 1950s, several books contained water paintings and from the 1970s onwards textbooks had colour photographs. Soil profile depictions were merely used to illustrate different orders in a classification system. Since
  • the 1990s, efforts have been made to depict the soil profile in 3D. The overall trends and pattern found in this analysis not only reflect the technical ability to depict soils (e.g. camera, printing techniques) but also reflect the state of knowledge
  • on the key properties and processes that have formed a soil.
  • 2009
  • [b1] ISRIC - World Soil Information, Wageningen, Pays-Bas
  • Erosion processes in Slovene Istria. Part 1, Soil erosion
  • Forest ; Geomorphology ; Meadow ; Slovenia ; Soil erosion ; Soil science
  • of flysch debris along erosion gullies, and geomorphic processes on talus slopes. At the same time, measurements of soil erosion were made in three different land use areas: bare soil in an olive grove, an overgrown meadow, and a forest. - (L'A.).
  • 2009
  • Soil indicators for eco-geographic regionalization : a case study in mid-temperate zone of eastern China
  • China ; Eastern China ; Ecogeography ; Ecosystem ; Indicator ; Principal components analysis ; Soil ; Soil properties ; Spatial distribution ; Temperate zone
  • , soil types were often taken as a basis for soil regionalization. Based on the second China's national soil survey data and the provincial soil resource information, by principal analysis and discriminant analysis, this paper dicusses the appropriate
  • soil indicators as the complement of eco-geographic region indicator systems and the relationships between these soil indicators and soil types in regionalization. The results show that 5 indicators are used in eco-geographic zonality in mid-temperate
  • zone of eastern China which are organic matter content, cation exchange capacity, pH, clay content and bulk density in topsoils. By cluster analysis it is proved that these soil indicators are better than the soil types and soil regionalization
  • 2009
  • [b1] Inst. of Geographic Sciences and Natural Resources Research, Beijing, Chine
  • [b2] Graduate University of Chinese Academy of Sciences, Beijing, Chine
  • Time stability of soil water storage measured by neutron probe and the effects of calibration procedures in a small watershed
  • China ; Geophysics ; Land use ; Loess ; Organic materials ; Plateau ; Shaanxi ; Soil properties ; Soil water ; Spatial variation ; Vegetation ; Watershed
  • The knowledge of soil water storage (SWS) of soil profiles is crucial for the adoption of vegetation restoration practices. With the aim of identifying representative sites to obtain the mean SWS of a watershed, a time stability analysis of neutron
  • probe evaluations of SWS was performed by the means of relative differences and Spearman rank correlation coefficients. Correlation analysis showed that the neutron probe calibration was linked to soil bulk density and to organic matter content
  • . Therefore, spatial variability of soil properties should be taken into account during the process of neutron probe calibration. This study provides useful information on the mean SWS observation with a time stable site and on distinct neutron probe
  • calibration procedures, and it should be extended to soil water management studies with neutron probes, e.g., the process of vegetation restoration in wider area and soil types of the Loess Plateau in China.
  • 2009
  • [b1] Key Lab. of Water Cycle and Related Surface Processes, Inst. of Geographic Sciences and Natural resources Research, CAS, Beijing, Chine
  • [b2] State Key Lab. of Soil Erosion and Dryland Farming on the Loes Plateau, Inst. of Soil and Water Conservation, CAS, Univ., Yangling, Chine
  • [b3] Graduate Univ. of Chinese Academy of Sciences, Beijing, Chine
  • [b4] Lab. of Soil Physics, Center for Nuclear Energy in Agriculture, Univ., São Paulo, Bresil
  • Land use history and historical soil erosion at Albersdorf (northern Germany) - Ceased agricultural land use after the pre-historical period
  • Agricultural land use ; C 14 dating ; Erosion rate ; Geoarchaeology ; Geomorphology ; Germany ; Historical period ; Land use ; Landscape ; Neolithic ; Schleswig-Holstein ; Soil erosion ; Soil properties ; Watershed
  • The Holocene landscape history and historical soil erosion were reconstructed at Albersdorf (Schleswig-Holstein) from soils and colluvial layers. In contrast to many landscapes in central Europe, agricultural land use and soil erosion were more
  • frequent during pre-historical times, whereas it has almost ceased after the advent of history. Pre-historical soil erosion rates were reconstructed with no significant differences between the prehistoric cultural phases. The study of buried soils within
  • the soil/soil-sediment-sequences provided evidence for an acceleration of soil formation processes probably as a consequence of excessive prehistoric woodland pasture on poor sandy soils. The results from Albersdorf are compared with data from other sites
  • 2009
  • [b1] Ministry of Science, Research and Culture of the state Brandenburg, Postdam, Allemagne
  • [a1] Dep. of Earth and Environmental Science, K.U., Leuven, Belgique
  • The stone and boulder content of Swedish forest soils
  • Forest soil ; Inventory ; Soil ; Soil properties ; Spatial analysis ; Sweden
  • Stone and boulder content has a strong influence on many soil processes and is a crucial factor to take into account when estimating element pools. In this paper, the AA. present the results of a large scale inventory of the stone and boulder
  • content of forest soils, which employed a surface penetration method (Viro's method) in 1943 plots across Sweden. A relationship was found between stone and boulder content and surface boulder frequency, but the strength of the relationship varied
  • regionally. In some regions surface boulders may provide an indicator of stone and boulder content in the soil.
  • 2009
  • [b1] Swedish Univ. of Agricultural Sciences, Dep. of Soil and Environment, Uppsala, Suede
  • Occurrence and hydrological effects of water repellency in different soil and land use types in Mexican volcanic highlands
  • Ecosystem ; Forest ; Land use ; Mexico ; Michoacán ; Permeability ; Pyroclastic ; Soil erosion ; Soil properties ; Vegetation ; Volcanic ash ; Volcanic soil ; Water erosion
  • In this study the occurrence and hydrological effects of water repellency were investigated at a plot scale for different types of land use and volcanic soils in Mexican volcanic highlands from Michoacan, Mexico: [1] fir, pine and oak mixed forest
  • soils developed from lavas, [2] soils developed from volcanic ashes and pyroclastic sediments under sparse fir, pine and oak forest and shrubland, [3] pine and oak forested soils developed from lavas and pyroclastic sediments, and [4] bare soils
  • on recent ash sediments in plain surfaces. Shallow and irregular wetting fronts were observed at water-repellent zones, reducing the soil water storage capacity. The implications of soil water repellency in soil hydrology and erosion risk in the area shed
  • light on the soil hydrology of the studied ecosystems, and can contribute to develop better management policies.
  • 2009
  • [b3] Lab. Soil Science, San Nicolás de Hidalgo Michoacan Univ., Morelia, Mexique
  • Soil development on Late Quaternary river terraces in a high montane valley in Bhutan, Eastern Himalayas
  • Bhutan ; Chemical erosion ; Chronosequence ; Fluvial terrace ; Geochemistry ; High mountain ; Himalaya ; Loess ; Micromorphology ; Pedogenesis ; Quaternary ; Soil ; Weathering
  • The AA. examined the geochemistry and micromorphology of the soils on a suite of morphologically well-defined and visually distinct fluvial terraces, up to 40 m elevation above the current riverbed, at Thangbi in the upper Bumthang Valley, Bhutan
  • . The soils are interpreted mainly as a monoclinal post-incisive chronosequence. The overall impression is of limited pedogenesis, even in the soils on the higher terraces. The AA. examine possibilities that the immaturity of the soils is due to pedogenic
  • rejuvenation by post-incision additions to the soil parent materials.
  • 2009
  • [b2] Inst. of Soil Science, Technical Univ., Munich, Allemagne
  • [b3] Inst. of Soil Science and Forest Nutrition, Univ., Freiburg, Allemagne
  • [b1] National Soil Services Centre, Ministry of Agriculture, Bhoutan
  • [b6] National Soil Resources Inst., Univ., Cranfield, Royaume-Uni
  • The humped soil production function : eroding Arnhem Land, Australia
  • Australia ; Erosion rate ; Geochemistry ; Isotope analysis ; Northern Territory ; Sediment transport ; Soil erosion ; Tropical zone ; Water erosion ; Weathering
  • The AA. report erosion rates and processes, determined from in situ-produced 10Be and 26Al across a soil-mantled landscape of Arnhem Land, northern Australia. Soil production rates peak under a soil thickness of about 35 cm and they observe no soil
  • thicknesses between exposed bedrock and this thickness. These results thus quantify a well-defined humped soil-production function, in contrast to functions reported for other landscapes. They compare this function to a previously reported exponential decline
  • of soil production rates with increasing soil thickness across the passive margin exposed in the Bega Valley, south-eastern Australia, and found remarkable similarities in rates. Quantifying such rates and processes help determine spatial variations
  • of soil thickness as well as helping to predict the sustainability of the Earth's soil resource under different erosional regimes.
  • 2009
  • [b2] Australian Nuclear Science and Technology Organisation (ANSTO), NSW, Menai, Australie
  • [b3] School of Environmental and Life Sciences, Univ. of Newcastle, Callaghan, Australie
  • Assessing parent material uniformity of a red and black soil complex in the landscapes
  • Australia ; Geochemistry ; Grain size distribution ; Micromorphology ; Pedogenesis ; Soil ; Soil properties ; South Australia ; Weathering
  • The distribution of red and black soil (Xeralfs-Xerolls) associations in the Monarto area (South Australia) is complex and their genesis either being derived from a uniform parent material or a lithologic discontinuity is not known. Hence, the aims
  • may be responsible for the textural contrast within the red and black soil profiles.
  • 2009
  • [b1] Dep. of Soil Science, Waite Agricultural Research Inst., Univ., Adelaide, Australie
  • [b2] Div. of Soils, CSIRO, Glen Osmond, Australie
  • Biological indicator ; Ecosystem ; Heavy metals ; Hungary ; Soil ; Soil pollution ; Soil properties ; Urban area
  • Nowadays, urban soils attract more and more attention, as they are one of the key elements of the urban ecosystem. The determination of their properties is of great importance both from the aspect of soil science and human health. Therefore, soil
  • samples were taken at 25 sites from horizons of soil profiles located in the downtown and surroundings of Szeged (S-Hungary) in order to examine diagnostic properties different from natural soils. Furthermore, average topsoil samples were taken citywide
  • 2009
  • Improvements of water-stability of clay aggregates admixed with aqueous polymer soil stabilizers
  • Aggregate ; Applied geomorphology ; Clay ; Erosion control ; Experimentation ; Mass movement ; Microstructure ; Slope ; Soil erosion ; Soil properties ; Structural stability
  • Aqueous soil stabilizers improve soil properties. Water-stability of soil aggregates was determined using 2 different soil stabilizers : S-type and E-type. Various concentrations of the 2 soil stabilizers were tested in soil aggregates (5-10 mm
  • ). Testing the aggregates using the static water-measure method showed that the water-satbility index, K, increased with the concentration of soil stabilizers. Two aggregate collapse models were found and discussed. Their pattern depends on the formation
  • 2009
  • [b1] The School of Earth Sciences and Engineering, Univ., Nanjing, Chine
  • [b2] The School of Geographic and Oceanographic Sciences, Univ., Nanjing, Chine
  • Spatiotemporal features of soil and water loss in Three Gorges Reservoir Area of Chongqing
  • Biodiversity ; China ; Chongqing ; Dam ; Environmental degradation ; Geographical information system ; Land use ; Reservoir ; Soil erosion ; Soil properties ; Soil water ; Spatial analysis ; Water resources ; Watershed
  • The AA. studied the spatiotemporal features of soil and water loss in the Three Gorges Reservoir Area (TGRA) from 1999 to 2004 based on RS and GIS techniques. Results and discussion on the analysis of the correlation between soil and water loss
  • and soil types, land use types, topography, rainfall. The aim of this paper is to further discuss the basic driving mechanism to the changes of soil and water loss, simulate and forecast soil and water loss in the TGRA and its response to eco-environment
  • , so as to lay a foundation for establishing an effective mechanism to improve soil and water conservation and the eco-environmental quality in the TGRA.
  • 2009
  • [b1] College of Resources and Environmental Science, Univ., Chongqing, Chine
  • [b2] College of Geographical Science, Normal Univ., Chongqing, Chine
  • An overview of soil loss tolerance
  • Agropedology ; Erodibility ; Erosion control ; Risk ; Soil ; Soil erosion ; Soil properties
  • As the criterion for judging whether a soil has potential risks of erosion, productivity loss and whether a river has downstream over-sedimentation as well as the ultimate criterion for erosion control for the preservation of soil productivity
  • and environmental security in the long term, the level of soil tolerance (T value) must be determined in a scientific manner. This overview summarized the development of T value. The factors influencing T value were then discussed, and the calculation methods for T
  • value were also presented and evaluated. Two key issues, which can prevent the damage by soil erosion, i.e. tolerance for agrochemicals and self-restoration capacity of ecological environments should be addressed in the near future.
  • 2009
  • [b1] Inst. of Geographic Sciences and Natural Resources Research, Beijing, Chine
  • [b3] Graduate School of Chinese Academy of Sciences, Beijing, Chine
  • [b4] Dep. of Environmental Sciences, Univ. California, Riverside, Etats-Unis
  • Soil microaggregates stability under different land use types in southeastern Nigeria
  • Aggregate ; Clay mineral ; Land use ; Nigeria ; Soil erosion ; Soil properties ; Soil water ; Statistical analysis
  • Low water stability of soil microaggregates accentuated by increased intensity of cultivation, high soil erodibility and climatic erosivity has become a major cause of increased water erosion process on agricultural lands in Imo Statea. Thus
  • , this study was conducted in 2006 to quantify the effects of different land use types (LUTs) on the water stability of their various soil microaggregates in the area. Six LUTs [natural forest (NF); oil palm plantation (OPP); plantain plantation (PP); rubber
  • plantation (RP); bush fallow (BF) and continuous cassava cropping (CCC)] were chosen for the study. The soil microaggregate stability was measured by clay dispersion ratio (CDR) and aggregated silt and clay, ASC (%) indices. Results showed that the CDR
  • obtained from soil under NF LUT was significantly lower (implying higher microaggregate stability) than what were obtained from other LUT soils. Correlation of each of the microaggregate stability indices (CDR and ASC) with some soil properties suggested
  • 2009
  • [b1] Dep. of Soil Science and Technology, Federal Univ. of Technology, Owerri, Nigeria
  • Arid area ; Erosion control ; Erosion rate ; Fire ; Litter ; Mediterranean area ; Permeability ; Rainfall simulation ; Soil erosion ; Soil properties ; Spain ; Splash ; Water erosion
  • This paper describes the changes in soil water repellency and soil hydrological and erosional responses to rainfall at small-plot scale, arising from a prescribed fire immediately following burning and one year later in a Mediterranean heathland
  • in the area of the Strait of Gibraltar. Although wildfires will increase soil erodibility, the trends observed in this study suggest that this increased susceptibility to erosion from rainsplash processes may be limited while an intact ash and charred litter
  • 2009
  • [b1] Division of Soil Science, Dep. of Crystallography, Mineralogy and Agricultural Chemistry, Univ., Sevilla, Espagne
  • [b2] Division of Soil Science, Dep. of Agricultural Chemistry and Soil Science, Univ., Córdoba, Espagne
  • Thermal characterisation of active layer across a soil moisture gradient in the McMurdo Dry Valleys, Antarctica
  • Active layer ; Antarctica ; Climatic change ; Energy balance ; Numerical model ; Periglacial features ; Soil moisture ; Soil temperature
  • Here, the AA. present results of a study to characterise soil thermal properties along a soil moisture gradient adjacent to Lake Fryxell in Taylor Valley, Antarctica. The goals were to characterise the thermal characteristics of these relatively wet
  • soils (compared to the rest of the McMurdo Dry Valleys landscape), and to assess the response of the active layer to possible increases in soil moisture. The AA. measured subsurfaces temperatures at depths from 3 to 50 cm at 4 locations along a natural
  • gradient of wet to dry soils adjacent to Lake Fryxell from January 2006 to January 2007. They used a numerical model to estimate apparent thermal diffusivity (ATD) and simulate observed temperature time series. Estimated bulk ATD values were consistently
  • greater in locations of enhanced soil moisture, so lakeside soils were more likely to conducte energy into the subsurface. Increased soil moisture across the landscape would likely increase ATD, allowing for greater heat exchange between the atmosphere
  • 2009
  • [b3] Dept. of Biological Sciences, Virgini Polytechnic Univ., Blacksburg, Etats-Unis
  • Biogeochemistry ; Carbon ; Deciduous forest ; Lithology ; Mountain ; Organic materials ; Precipitation ; Slope exposure ; Soil ; Soil properties ; Spain
  • The aim of this study was to determine the effect of bedrock, mean annual precipitation (MAP) and slope orientation (SLO) on soil C accumulation under deciduous forests on the Sierra de Gata Mountains in the Central Iberian Massif (central western
  • Spain). An evaluation of the influence of diagnostic horizon soil properties on that C-sequestration process was also performed.
  • 2009
  • [b1] Area of Soil Science and Soil Chemistry, E.T.S.II.AA., Univ. of Valladolid, Palencia, Espagne
  • Accounting for extensive topographic and pedologic secondary information to improve soil mapping
  • Central Italy ; Digital elevation model ; Geostatistics ; Italy ; Krigeage ; Methodology ; Multivariate analysis ; Siena ; Soil map ; Soil properties ; Soil science ; Soil water ; Spatial variation ; Topography
  • The aim of this paper was to find the method that best improves the estimation of primary attributes through dense secondary information for the study area, the province of Siena in central Italy. Soil samples were taken at 742 locations and depth
  • , sand and clay contents and available water capacity were determined. A multivariate geostatistical analysis was performed using the 4 soil properties and elevation from a digital elevation model of 20x20 m resolution as auxiliary variable. The variables
  • were interpolated using 3 different approaches : cokriging, multicollocated cokriging, multicollocated simple kriging with local mean, estimated by averaging over the soil unit occurring at each node of the interpolation grid. These methods were
  • compared in terms of precision, through cross validation, and of accuracy, through a validation test, using an independent data set of 170 soil depth measurements. The results did not show clear differences among the methods.
  • 2009