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  • Organic carbon accumulation in a 2000-year chronosequence of paddy soil evolution
  • Agricultural land use ; Carbonate ; China ; Chronosequence ; Clay mineral ; Humid environment ; Organic materials ; Pedogenesis ; Rice ; Soil ; Soil properties ; Zhejiang
  • Based on a chronosequence derived from marine sediments, the aims of this study are to investigate the accumulation of organic carbon (OC) and the concurrent loss of inorganic carbon (IC) and to identify the role of the soil fractions
  • for the stabilization of OC with increasing duration of paddy soil management. A chronosequence of 6 age groups of paddy soil formation was chosen in the Zhejiang Province (PR China), ranging from 50 to 2000 years (yrs) of paddy management. Soil samples obtained from
  • horizontal sampling of 3 soil profiles within each age group were analyzed for bulk density (BD), OC as well as IC concentrations, OC stocks of bulk soil and the OC contributions to the bulk soil of the particle size fractions. The silt fraction showed a high
  • accretion of OC and seems to be an important long-term OC sink during soil evolution. With longer paddy management, the fractions < 20 μm showed an increasing actual OC saturation level, but did not reach the calculated potential storage capacity.
  • 2011
  • [b2] Soil Sciences, Martin-Luther Univ., Halle, Allemagne
  • [b3] Inst. of Environment and Soil Fertilizer Research, Zhejiang Academy of Agricultural Sciences, Hangzhou, Chine
  • [b4] Inst. of Soil Science, CAS, Nanjing, Chine
  • [b1] Lehrstuhl für Bodenkunde, Dep. Ecology and Ecosystem Sciences, Center of Life and Food Sciences Weihenstephan, Technische Univ., Freising, Allemagne
  • Using Canonical Correspondence Analysis (CCA) to identify the most important DEM attributes for digital soil mapping applications
  • Canonical correspondence analysis ; Cartography ; Digital elevation model ; Iran ; Soil ; Soil properties ; Spatial distribution ; Topography
  • The aim of this study was to analyze relationships between topographical properties derived from DEM and soil distribution and to discuss their applicability in Digital Soil Mapping (DSM). The study was carried out in the Borujen area of central
  • Zagros, Iran. A total of 13 plots were set up to calculate the percentages of the dominant soil series. Fifteen DEM attributes, including slope, aspect, curvature, maximum and minimum curvature, planform curvature, profile curvature, tangent curvature
  • relationships. The results obtained show that there was a relatively strong correspondence between soils' series distribution and topographical properties.
  • 2011
  • [b1] Soil Science Dep., College of Agriculture, Univ., Shahrekord, Iran, Republique Islamique d'
  • [b2] Dep. of Environment and Soil Science, Univ., Lleida, Espagne
  • [b4] Soil Science Dep., College of Agriculture, Vali-e-Asr Univ., Rafsanjan, Iran, Republique Islamique d'
  • Use of palm-mat geotextiles for soil conservation : I. Effects on soil properties
  • Aggregate ; England ; Experimentation ; Geotextile ; Organic materials ; Shropshire ; Soil ; Soil conservation ; Soil properties ; United Kingdom
  • Field experiments were conducted at Hilton, east Shropshire, U.K. during 2007–2009, to study the impacts of Borassus and Buriti mats on selected properties of the topsoil. Ten fixed plots were established, with duplicate treatments : (i) bare soil
  • ; (ii) permanent grassed; (iii) bare soil with 1 m Borassus-mat buffer strips at the lower end of the plots; (iv) bare soil with 1 m Buriti mat buffer strips at the lower end of the plots; and (v) completely-covered with Borassus mats. Initial and final
  • soil samples of the topsoil were collected and analysed for bulk density, aggregate stability, soil organic matter (SOM), total soil C (TSC), total soil N (TSN) and pH. Results and discussion. In summary, utilization of Borassus mats as buffer strips
  • was very successful in conserving soil properties on a loamy sand soil.
  • 2011
  • [b1] School of applied Sciences, Univ., Wolverhampton, Royaume-Uni
  • Spatial delineation of organic carbon-rich colluvial soils in chernozem regions by terrain analysis and fuzzy classification
  • Chernozem ; Czech Republic ; Digital elevation model ; Fuzzy logic ; Geomorphometry ; Loess ; Microrelief ; Model ; Moravia ; Soil erosion ; Spatial distribution ; Topography
  • A method of delineating Colluvial soils is proposed by applying a combination of high resolution digital elevation model analysis and detailed field survey. Two models based on fuzzy classification of soil units were created using different
  • topographic derivatives as the only input parameters to predict the Colluvial soil area on a morphologically diverse study site in the Southern Moravia, Czech Republic. The model that considers only the derivatives with a strong relationship to Colluvial soil
  • occurrence reached 71% accuracy in Colluvial area delineation, while the model combining six commonly used derivatives showed less favorable results. The main advantage of the method lies in a low demand of input soil data and its relatively high accuracy.
  • 2011
  • [b1] Dep. of Soil Science and Soil Protection, Czech Univ. of Life Sciences, Prague, Tcheque, Republique
  • [b3] Dep. of Physical Geography and Geoecology, Fac of Science, Charles Univ., Prague, Tcheque, Republique
  • Impact of subsurface rock fragments on runoff and interrill soil loss from cultivated soils
  • Belgium ; Cultivated land ; Erosion rate ; Experimentation ; Infiltration ; Rainfall simulation ; Rill wash ; Rock fragment ; Soil erosion ; Soil properties ; Splash ; Water erosion
  • In this study interrill laboratory experiments with simulated rainfall for 60 min were conducted to assess the influence of subsurface rock fragments incorporated in a disturbed silt loam soil at different depths below the soil surface
  • , on infiltration, surface runoff and interrill erosion processes for small and large rock fragment sizes. Although only small differences in infiltration rate and runoff volume are observed between the soil without rock fragments (control) and the one
  • with subsurface rock fragments, considerable differences in total interrill soil loss are observed between the control treatment and both contrasting rock fragments sizes. This is explained by a rapid increase in soil moisture in the areas above the rock fragments
  • and therefore a decrease in topsoil cohesion compared with the control soil profile. The results highlight the impacts and complexity of subsurface rock fragments on the production of runoff volume and soil loss and requires their inclusion in process-based
  • 2011
  • [b1] Dep. of Earth and Environmental Sciences, K. Univ., Geo-Inst., Heverlee, Belgique
  • [b3] Dep. of soil and Water, EEAD-CSIC, Zaragoza, Espagne
  • Assessment of soil erodibility in Taleghan drainage basin, Iran, using multivariate statistics
  • Cluster analysis ; Erodibility ; Factor analysis ; Iran ; Land use ; Multivariate analysis ; Principal components analysis ; Soil erosion ; Soil properties ; Watershed
  • The AA. use geological mapping and cluster, principal component, and factor analysis to group soils in the Taleghan Drainage Basin in Iran and subsequently determine their erodibility. Physical and chemical properties that might impact soil
  • erodibility were used to create a matrix of soil properties and parent material. Application of cluster analysis and factor analysis to the data allowed identification of 3 geological (parent material) clusters. To investigate the mutual effect of land use
  • and parent material on soil erodibility, a soil erodibility factor was obtained for 3 land use types in each cluster: rangeland, cropland (irrigated), and dry-land farming (nonirrigated). The study suggests that geological and land use maps provide a useful
  • framework for assessing soil erodibility.
  • 2011
  • [b5] Dep. of Crop and Soil Sciences, State Univ., Pennsylvania, Etats-Unis
  • [b1] Dep. of Physical Geography, Fac. of Earth Sciences, Shahid Beheshti Univ., Tehran, Iran, Republique Islamique d'
  • Changes in soil properties across a chronosequence of vegetation restoration on the Loess Plateau of China
  • China ; Chronosequence ; Ecological restoration ; Land use ; Loess ; Plateau ; Shaanxi ; Soil ; Soil properties ; Watershed
  • The AA. compared soil properties of the Yanhe Watershed in northern Shaanxi across 5 different land uses (shrubland, farmland, natural grassland, woodland and artificial grassland) and a chronosequence of soils undergoing restoration for 5, 10, 15
  • , 20, 25, 30, 35, 40 and 45 years. They found that revegetation had a positive effect on soil bulk density decrease, total porosity and capillary porosity increase in the surface soil layers but not in the subsurface layer. Additionally, soil organic
  • that revegetation on eroded soil can produce important increases in soil fertility on older plantations and in areas with natural succession.
  • 2011
  • [b2] Inst. of Soil and Water Conservation, Chinese Academy of Science and Ministry of Water Resources, Shaanxi, Yangling, Chine
  • [b1] Inst. of Soil and Water Conservation, Northwest A and F Univ., Yangling, Chine
  • Surface chemical properties and pedogenesis of tropical soils derived from basalts with different ages in Hainan, China
  • Basalt ; China ; Clay mineral ; Geophysics ; Guangdong ; Hainandao ; Pedogenesis ; Soil properties ; Tropical zone ; Weathering
  • Soil samples of 3 profiles derived from basalts of 10, 1330 and 2290 kilo annum (ka) in age were collected from adjacent locations in a tropical region of Hainan Province, China. The changes in soil surface chemical properties and the mineralogy
  • of the soil clay fraction with time were investigated using ion adsorption, micro-electrophoresis, and X-ray diffraction analysis. It is highlighted that the content of kaolinite and gibbsite increased with increasing basalt age and degree of soil development
  • . The positive surface charge of the soils increased with increasing basalt age and degree of soil development. Increasing age also elevated the point of zero net charge of the soil and the isoelectric point of soil colloids.
  • 2011
  • [b1] State Key Lab. of Soil and Sustainable Agriculture, Inst. of Soil Sciences, CAS, Nanjing, Chine
  • C 14 dating ; Classification ; Environmental degradation ; Geochemistry ; Heavy metals ; Nutrient ; Peat bog ; Soil properties ; Turkey
  • in the study area and soil samples were taken based on soil horizons. Additionally, soil samples were taken at the different depths in each profile for radiocarbon dating. It was observed that seasonal ground water fluctuations, eutrophic formation
  • and differences in decomposition degrees have a substantial effect on changing of morphological and chemical properties of organic soils in the study area.
  • 2011
  • [b1] Dep. of Soil Science, Fac. of Agriculture, Univ., Ankara, Turquie
  • [b2] Dep. of Soil Science, Fac. of Agriculture, Selcuk Univ., Konya, Turquie
  • [b3] Dep. of Soil Science, Fac. of Agriculture, YuzuncuYil Univ., Van, Turquie
  • Effects of soil erosion on long-term soil productivity in the black soil region of northeastern China
  • Agricultural productivity ; Agropedology ; China ; Cultivated land ; Impact ; Index ; Model ; North-Eastern China ; Soil erosion
  • China's northeastern Black Soil Region, one of the country's most important crop production areas, has been seriously affected by soil erosion. This study evaluated the effects of soil erosion on the long-term productivity of this region. The AA
  • . used a modified productivity index (MPI) model to assess the current effects of soil erosion on soil productivity, as well as to predict long-term change in productivity. The model predicts a 9.6% productivity reduction over 100 years and a 48.3
  • 2011
  • [b3] Regional Climate group, Dep. of Earth Sciences, Univ., Gothenburg, Suede
  • Atypical soil carbon distribution across a tropical steepland forest catena
  • Carbon ; Catena ; Forest ; Geochemistry ; Litter ; Model ; Nitrogen ; Organic materials ; Puerto Rico ; Slope gradient ; Soil ; Soil properties ; Spatial distribution ; Tropical zone ; Vegetation
  • Soil organic carbon (SOC) in a humid subtropical forest in Puerto Rico is higher at ridge locations compared to valleys, and therefore opposite to what is commonly observed in other forested hillslope catenas. To better understand the spatial
  • distribution of SOC in this system, plots previously characterized by topographic position, vegetation type and stand age were related to soil depth and SOC. Additional factors were also investigated, including topographically-related differences in litter
  • dynamics and soil chemistry. To investigate the influence of litter dynamics, the Century soil organic model was parameterized to simulate the effect of substituting valley species for ridge species. Soil chemical controls on C concentrations were
  • 2011
  • [b1] Dep. of Earth and Environmental Science, Univ. of Pennsylvania, Philadelphia, Etats-Unis
  • [b2] Dep. of Environmental Science, Policy and Management, Univ. of California, Berkeley, Etats-Unis
  • Temporal variation of soil organic matter content and potential determinants in Tibet, China
  • Asia ; Climatic change ; Mountain ; Organic materials ; Over-grazing ; Soil ; Soil properties ; Tibet
  • The main aim of this study was to investigate temporal variations in SOM content in Tibetan soils as an important indicator of climate change. SOM content data were obtained from soil surveys conducted in the 1980s and resampled in the 2000s
  • . In this study, SOM content data from the A horizon of the soil profile were compared over time, and a paired t-test was conducted to verify differences between the 2 datasets. To determine the causes of SOM content decreases in the A horizon, soil samples were
  • grouped into 10 soil types, 4 land-use types, and 7 physiogeographical units. Based on the analysis of some known realities, this change should be attributed to pasture degradation resulting from overgrazing and climate warming.
  • 2011
  • [b3] Key Lab. of Mountain Hazards and Earth Surface Processes, Chinese Academy of Sciences, Chengdu, Chine
  • [b4] Graduate School of Chinese Academy of Sciences, Beijing, Chine
  • Soil seed bank composition and distribution on eroded slopes in the hill-gully Loess Plateau region (China): influence on natural vegetation colonization
  • China ; Ecological restoration ; Erosion control ; Experimentation ; Germination ; Gully erosion ; Loess ; Plant colonization ; Plateau ; Shaanxi ; Soil erosion ; Vegetation ; Water erosion ; Watershed
  • In this work, soil seed bank composition and distribution were studied in 3 main microsites selected as sampling plots : fish-scale pits, as artificial deposited micro-topography; under tussocks, as trap microsites; and open areas, as eroded areas
  • . Soil samples were collected at 3 depths. The soil seed bank was identified using germination experiments, and a total of 34 species were identified. The dominant species in the soil seed bank were annual/biennial herbs with an average proportion more
  • than 90%. Compared with the eroded open areas, the fish-scale pits retained a higher density of seeds, and the tussocks retained a larger number of species. However, there was no serious reduction of the soil seed bank in the erosion areas. The present
  • study indicates that, on these eroded slopes, the soil seed bank is not the key factor limiting the colonization of natural vegetation.
  • 2011
  • [b2] Inst. of Soil and Water Conservation, Chinese Academy of Science and Ministry of Water Resources, Shaanxi, Yangling, Chine
  • [b1] Inst. of Soil and Water Conservation, Northwest A and F Univ., Yangling, Chine
  • Evaluating the impact of soil redistribution on the in situ mineralization of soil organic carbon
  • Belgium ; Carbon ; Cultivated land ; Experimentation ; Flemish Brabant ; Geochemistry ; Loess ; Soil ; Soil erosion ; Soil properties ; Water erosion
  • situation on the field ensured that almost none of eroded SOC was exported from the field. Field data were complemented by measurements on incubated, undisturbed soil core samples, in order to disentangle the contribution of environmental factors (moisture
  • , temperature) from any erosional effect on CO2-efflux. Results of these measurements on the field showed that CO2-efflux was regulated by a complex interplay of different factors (mostly soil porosity, soil moisture and soil temperature). In combination
  • 2011
  • [b1] Dep. of Earth and Environmental Science, K.U., Leuven, Belgique
  • Intensive soil erosion periods of Pleistocene on the Central South Loess Plateau
  • China ; Isotope analysis ; Loess ; Magnetic susceptibility ; Oxygen 18 ; Palaeo-environment ; Palaeosol ; Plateau ; Pleistocene ; Shaanxi ; Soil erosion
  • In this study, the AA. analyze the environmental condition that may have caused intensive soil erosion and define what kind of relics can be considered as erosion surfaces. They present results of the field work at Luochuan, Weinan, Tongchuan
  • 2011
  • [b1] State Key Lab. of Soil Erosion and Dryland Farming on the Loes Plateau, Inst. of Soil and Water Conservation, CAS, Univ., Yangling, Chine
  • [b3] Univ. of Chinese Academy of Sciences, Beijing, Chine
  • Soil moisture variability along transects over a well-developed gully in the Loess Plateau, China
  • Arid area ; China ; Gully erosion ; Loess ; Plateau ; Semi-arid area ; Shaanxi ; Soil erosion ; Soil moisture ; Soil properties ; Spatial variation ; Water erosion
  • The AA. examined soil moisture profiles and their variability along 3 transects traversing sidewalls of a well-developed gully with steep slopes in a hilly area of the Chinese Loess Plateau. Revised fitting functions developed and introduced
  • by Famiglietti et al. (2008) captured with confidence the relationship between spatial variability (SD and CV) and spatial mean of moisture content (RMSE). Soil moisture clearly varied along the transects, the vertical distribution of soil moisture differed
  • in different seasons, and correlation analysis showed that soil texture influenced the variability of surface soil moisture more strongly than terrain attributes (except during distinct rainfall events, when this pattern reversed). The results presented here
  • should improve understanding of spatio-temporal variations in soil moisture profiles in well-developed gullies in the Loess Plateau, and potentially elsewhere.
  • 2011
  • [b1] Inst. of Soil and Water Conservation, Chinese Academy of Science, Shaanxi, Yangling, Chine
  • [b4] Graduate Univ. of Chinese Academy of Sciences, Beijing, Chine
  • Soil loss rates due to piping erosion
  • Ardenne ; Belgium ; Collapse structures ; Erosion rate ; Loess ; Piping ; Soil erosion ; Temperate zone ; Water erosion
  • In this study, the significance of soil loss due to piping is demonstrated through an estimation of soil volume lost from pipes and pipe collapses in parcels under pasture on loess-derived soils in a temperate humid climate (Belgium). The results
  • obtained for the study area in the Flemish Ardennes correspond well to other measurements in temperate environments; they are, however, considerably smaller than soil loss rates due to subsurface erosion in semi-arid environments. Although local slope
  • 2011
  • [b3] Div. of Soil and Water Management, Dep. of Earth and Environmental Sciences, K.U., Leuven, Belgique
  • [b1] Div. Geography, Dep. of Earth and Environmental Sciences, K.U., Leuven, Belgique
  • Agricultural practice ; Agropedology ; China ; Cultivated land ; Experiment plot ; Maize ; Micro-organism ; Mulching ; North-Eastern China ; Seasonal variability ; Soil properties ; Soil temperature
  • Seasonal variability of microbial biomass carbon (MBC) and basal respiration (BR) in surface soil was compared between conventional straw removal (SR) and straw coverage (SC) in a maize field experiment, Northeast China. The straw coverage treatment
  • significantly increased microbial energy, carbon and nutrient sources (soil C and N contents) and improved soil physical environment (moisture and porosity), and thus stimulated MBC and BR across the growth season of maize, as compared to the straw removal
  • treatment. MBC and BR showed similar seasonal trends in soil temperature, with maximum values in summer. In both study years, the straw coverage treatment reduced seasonal variation of soil temperature, therefore it significantly moderated seasonal
  • variability of MBC and BR. These results demonstrate that straw coverage contributes to stabilizing soil microbial characteristics in season.
  • 2011
  • [b1] Inst. of Applied Ecology, Chinese Academy of Sciences, Shenyang, Chine
  • [b2] Inst. of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing, Chine
  • Effects of vegetation type on soil resistance to erosion: Relationship between aggregate stability and shear strength
  • Aggregate ; China ; Erosion control ; Human impact ; Landslide ; Soil erosion ; Soil properties ; Vegetation ; Water erosion
  • The AA. investigated the effect of vegetation on both soil aggregate stability and shear strength (through direct shear tests) in former croplands converted to vegetated erosion protection areas within the context of China's sloping land conversion
  • programme. Significant positive linear relationships were found between vegetation, soil aggregate stability and soil shear strength. Vegetation stabilised soil under different hierarchical levels of aggregate organisation, i.e. intra- and inter-aggregate
  • . As herbaceous vegetation was more efficient than trees in improving aggregate stability, it is suggested that mixtures of different plant functional types would improve soil conservation on slopes, by reducing both surface water erosion and shallow substrate
  • mass movement. Planting trees for cropping or logging, and removing understory vegetation is most likely detrimental to soil conservation.
  • 2011
  • [b2] Chinese Academy of Science, Yunnan, Mengla, Chine
  • Effect of snow amount on runoff, soil loss and suspended sediment during periods of snowmelt in southern West Siberia
  • Asian part of Russia ; Chernozem ; Freeze-thaw cycle ; Meltwater ; Runoff ; Snow ; Soil erosion ; Soil properties ; Suspended load ; Watershed ; West Siberia
  • Surface runoff, soil loss, suspended sediment concentration (SSC), texture of eroded soils and suspended sediment were determined on slightly eroded chernozems (mouldboard fall-ploughed) during years with different amounts of snow in three areas
  • of southern West Siberia (Predsalairye, Priobye and Kuznetsk hollow). These areas have different geomorphological and climatic characteristics and soils. Observations were made from 1969 to 2007. Soil losses in high-snow and very high-snow years varied from
  • slight to severe depending on studied area. Among the three studied regions, Predsalairye had decreased soil erosion resistance and was the area with the greatest danger of erosion.
  • 2011
  • [b1] Institute of Soil Science and Agrochemistry SB RAS, Novosibirsk, Russie, Federation de