WorldWideScience
1

Density and Stability of Soil Organic Carbon beneath Impervious Surfaces in Urban Areas  

OpenAIRE

Installation of impervious surfaces in urban areas has attracted increasing attention due to its potential hazard to urban ecosystems. Urban soils are suggested to have robust carbon (C) sequestration capacity; however, the C stocks and dynamics in the soils covered by impervious surfaces that dominate urban areas are still not well characterized. We compared soil organic C (SOC) densities and their stabilities under impervious surface, determined by a 28-d incubation experiment, with those i...

Wei, Zongqiang; Wu, Shaohua; Yan, Xiao; Zhou, Shenglu

2014-01-01

2

Land surface phenologies viewed in the middle infrared: seasonal contrasts between vegetation, soils, and impervious surfaces  

Science.gov (United States)

The middle infrared (MIR) region of the electromagnetic spectrum spans 3-5 microns. It is the mixing zone between reflected sunlight and emitted earthlight in roughly equal proportions. This region has received very little attention in terrestrial remote sensing. Yet the MIR merits exploration of how it could be used for monitoring land surface phenologies (LSP) and seasonalities due to five characteristics. First, green vegetation is MIR-dark, reflecting just 2-5% of the incident radiation. Second, soils are MIR-bright, reflecting up to one-third of the incident radiation. Third, impervious surfaces, such as concretes, asphalts, and other building and paving materials are also MIR-bright. Fourth, the resulting seasonal contrast in MIR between vegetated and non-vegetated surfaces lets urbanized areas emerge from the vegetated landscape. Fifth, MIR wavelengths penetrate anthropogenic haze and smoke because the particle radii are smaller. Here we use MODIS (MYD02) image time series to illustrate the temporal progressions of MIR at various wavelengths and how they compare to and diverge from the more familiar NDVI and derived LSP metrics.IR portrait of the USA east of W98: maximum value composite of Aqua MODIS MIR band 23 during DOY 219-233 of 2010.

Henebry, G. M.; Krehbiel, C.; Kovalskyy, V.

2012-12-01

3

Impacts of Spatial Distribution of Impervious Areas on Runoff Response of Hillslope Catchments: Simulation Study  

Science.gov (United States)

This study analyzes variations in the model-projected changes in catchment runoff response after urbanization that stem from variations in the spatial distribution of impervious areas, interevent differences in temporal rainfall structure, and antecedent soil moisture (ASM). In t...

4

Continental-scale Sensitivity of Water Yield to Changes in Impervious Cover  

Science.gov (United States)

Projected land conversion from native forest, grassland, and shrubland to urban impervious cover will alter watershed water balances by reducing groundwater recharge and evapotranspiration, increasing surface runoff, and potentially altering regional weather patterns. These hydrologic changes have important ecohydrological implications to local watersheds, including stream channel habitat degradation and the loss of aquatic biodiversity. Many observational studies have evaluated the impact of urbanization on water yield in small catchments downstream of specific urban areas. However it is often difficult to separate the impact of impervious cover from other impacts of urbanization such as leaking water infrastructure, irrigation runoff, water supply withdrawals, and effluent discharge. In addition, the impact of impervious cover has not been evaluated at scales large enough to assess spatial differences in water yield sensitivity to changes in impervious cover. The objective of this study was to assess the sensitivity of water yield to impervious cover across the conterminous U.S., and to identify locations where water yield will be most impacted by future urbanization. We used the Water Supply Stress Index (WaSSI) model to simulate monthly water yield as impacted by impervious cover for the approximately 82,000 12-digit HUC watersheds across the conterminous U.S. WaSSI computed infiltration, surface runoff, soil moisture, and baseflow processes explicitly for ten vegetative land cover classes and impervious cover in each watershed using the 2006 National Land Cover Dataset estimates of impervious cover. Our results indicate that impervious cover has increased total water yield in urban areas (relative to native vegetation), and that the increase was most significant during the growing season. The proportion of stream flow that occurred as baseflow decreased, even though total water yield increased as a result of impervious cover. Water yield was most sensitive to changes in impervious cover in areas where annual evapotranspiration is high relative to precipitation (e.g. the Southwestern States, Texas, and Florida). Water yield was less sensitive in areas with low evapotranspiration relative to precipitation (e.g. Pacific Northwest and Northeastern States). Additionally, water yield was most impacted when high evapotranspiration land cover types (e.g. forests) were converted to impervious cover than when lower evapotranspiration land cover types (e.g. grassland) were converted. Using projections of future impervious cover provided by the U.S. EPA Integrated Climate and Land Use Scenarios project, water yield in urban areas of the Southwest, Texas, and Florida will be the most impacted by 2050, in part because these areas are projected to have significant increases in impervious cover, but also because they are in areas where evapotranspiration is high relative to precipitation. Our study suggests that watershed management should consider the climate-driven sensitivity of water yield to increases in impervious cover and the type of land cover being converted in addition to the magnitude of projected increases in impervious cover when evaluating impacts of urbanization on water resources.

Caldwell, P.; Sun, G.; McNulty, S.; Cohen, E.; Moore Myers, J.

2012-12-01

5

Semi Impervious Subsurface Barrier for Water Conservation in Lateritic Formations  

Science.gov (United States)

The coastal districts of Karnataka in west coast of India experience acute shortage of drinking water during dry season in spite of heavy monsoon rains. Though sufficient recharge of ground water takes place, depletion of water table is very quick, once the rain recedes. It is mainly attributed to the presence of porous and highly permeable laterites and lateritic soils. The hydraulic conductivity of these soils varies in the range of 10-4 to 10-5 cm/s. The conventional water harvesting methods fail to solve the problem. It is necessary to explore innovative method to regulate the lateral subsurface flow and maintain a high water table over a prolonged period of time. The present work is an attempt to explore the possibility of using semi impervious Subsurface Barrier (SSB) to regulate and control the lateral flow of water in the unconfined aquifer in lateritic formations. Appropriate barrier material is arrived at using the locally available soil and the required properties are established. A SSB is built in a suitable location in an identified microwatershed using lateritic soil and the composite soil prepared by mixing requisite percentage of lateritic soil and clay. The hydraulic conductivity of these soils is maintained in the range of 10-6 to 10-7 cm/s so as to behave as semi impervious. The performance analysis is carried out by observing water levels in selected open observation wells before and after the construction of the barrier. The results have shown the successful performance of SSB in maintaining a high water table over a prolonged period of time during summer months, both in u/s and d/s of the barrier.

Udayakumar, G.; Mayya, S. G.

2014-09-01

6

Rerouting Urban Waters: A Historic Examination of the Age of Imperviousness  

Science.gov (United States)

From the 1600's to the 1900's landscapes along the Eastern United States underwent dramatic changes, including transitions from forest to production agriculture and eventually urban development. Legacy effects from decisions on sewer and water infrastructure built during the early 1900's are emerging today in degraded urban waterways. Impervious cover is often a factor used to predict water impairment. However, does imperviousness age or change through the course of landscape evolution? This study reconstructs the history of imperviousness in the Panther Hollow watershed (161 ha, Pittsburgh, PA) to examine these changes. We reconstruct the importance of factors influencing effective imperviousness from the 1800's to present including; (1) pipe and road network technological transitions, (2) land cover changes, particularly the loss of forest cover, and (3) modifications to local topography. Analysis reveals effective imperviousness (impervious area in the basin directly connected to stream channels) increased dramatically after 1900. Prior to 1900, water and sewer infrastructure was very limited. Local drainage networks generally followed the natural topography and households accessed water supplies from wells, precipitation harvesting or surface water. Road networks were sparse and predominantly dirt or aggregate surfaces. Forests and large family farms dominated land cover. Around 1910 public water supply expanded, significantly increasing effective imperviousness due to installation of brick and ceramic sewer infrastructure that routed waste waters directly to stream channels. Road networks also expanded and began transitioning from dirt roads to brick and eventually asphalt. Shifting to impervious paving materials required the installation of stormwater drainage. New drainage systems altered historic flow paths by re-routed large quantities of water through macro-pore sewer networks to local waterways. While this improvement prevented flooding to roadways, it also created new flooding issues downstream of outfalls. Improvements to transit networks also increased mobility and connected towns together facilitating the expansion of development. Significant losses of urban tree canopy cover and the loss of water storage capacity in soils compounded issues, dramatically increasing effective imperviousness. From 1940 - 1960 concerns over polluted waterways resulted in the re-routing of sewage networks from streams to treatment facilities, decreasing sewage subsidies to effective imperviousness. However, connection of stormwater drainage networks to sewage infrastructure designed for earlier flow regimes and the increasing effective imperviousness resulted in frequent overflows of sewage directly to local waterways. Currently, aging infrastructure presents the opportunity to incorporate low impact development techniques in infrastructure repair. This has the potential to reduce effective imperviousness in urban areas by re-establishing lost hydrologic flow paths. This research indicates imperviousness as a parameter incorporates a complicated mix of processes. Examining the causal, mechanistic links between these systems can provide additional perspective on water impairments in urban landscapes throughout the course of landscape evolution.

Hopkins, K. G.; Bain, D. J.

2011-12-01

7

Prior-knowledge-based spectral mixture analysis for impervious surface mapping  

Science.gov (United States)

In this study, we developed a prior-knowledge-based spectral mixture analysis (PKSMA) to map impervious surfaces by using endmembers derived separately for high- and low-density urban regions. First, an urban area was categorized into high- and low-density urban areas, using a multi-step classification method. Next, in high-density urban areas that were assumed to have only vegetation and impervious surfaces (ISs), the vegetation-impervious model (V-I) was used in a spectral mixture analysis (SMA) with three endmembers: vegetation, high albedo, and low albedo. In low-density urban areas, the vegetation-impervious-soil model (V-I-S) was used in an SMA analysis with four endmembers: high albedo, low albedo, soil, and vegetation. The fraction of IS with high and low albedo in each pixel was combined to produce the final IS map. The root mean-square error (RMSE) of the IS map produced using PKSMA was about 11.0%, compared to 14.52% only using four-endmember SMA. Particularly in high-density urban areas, PKSMA (RMSE = 6.47%) showed better performance than four-endmember (15.91%). The results indicate that PKSMA can improve IS mapping compared to traditional SMA by using appropriately selected endmembers and is particularly strong in high-density urban areas.

Zhang, Jinshui; He, Chunyang; Zhou, Yuyu; Zhu, Shuang; Shuai, Guanyuan

2014-05-01

8

Mapping impervious surfaces with the integrated use of Landsat Thematic Mapper and radar data: A case study in an urban-rural landscape in the Brazilian Amazon  

Science.gov (United States)

This research explored the integrated use of Landsat Thematic Mapper (TM) and radar (i.e., ALOS PALSAR L-band and RADARSAT-2 C-band) data for mapping impervious surface distribution to examine the roles of radar data with different spatial resolutions and wavelengths. The wavelet-merging technique was used to merge TM and radar data to generate a new dataset. A constrained least-squares solution was used to unmix TM multispectral data and multisensor fusion images to four fraction images (high-albedo, low-albedo, vegetation, and soil). The impervious surface image was then extracted from the high-albedo and low-albedo fraction images. QuickBird imagery was used to develop an impervious surface image for use as reference data to evaluate the results from TM and fusion images. This research indicated that increasing spatial resolution by multisensor fusion improved spatial patterns of impervious surface distribution, but cannot significantly improve the statistical area accuracy. This research also indicated that the fusion image with 10-m spatial resolution was suitable for mapping impervious surface spatial distribution, but TM multispectral image with 30 m was too coarse in a complex urban-rural landscape. On the other hand, this research showed that no significant difference in improving impervious surface mapping performance by using either PALSAR L-band or RADARSAT C-band data with the same spatial resolution when they were used for multi-sensor fusion with the wavelet-based method.

Lu, Dengsheng; Li, Guiying; Moran, Emilio; Batistella, Mateus; Freitas, Corina C.

2011-11-01

9

Determination effects of impervious areas on urban watershed.  

Science.gov (United States)

After the industrial revolution, urban growth has been increasing, especially with technological advances. Urbanization is accelerating environmental pollution and also affects climate significantly because of land use or land cover changes. In this study, the Hydrological Simulation Program-Fortran (HSPF) model developed by the United States Environment Protection Agency (USEPA) is used for modeling the impervious areas of Eski?ehir which is located in the Porsuk Stream Watershed in Inner Anatolia, Turkey. Effects of impervious areas of Eskisehir on the Porsuk Stream pollution between 1975 and 2010 have been investigated. Important water quality parameters like nitrate, orthophosphate, sediment, chloride, and total coliform are modeled. Impervious land segments have been found to be affecting all parameter concentrations and also surface flows significantly as determined using the t test with a confidence level of 95%. PMID:25182427

?im?ek Uygun, Burcu; Albek, Mine

2015-02-01

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A SUB-PIXEL ACCURACY ASSESSMENT FRAMEWORK FOR DETERMINING LANDSAT TM DERIVED IMPERVIOUS SURFACE ESTIMATES.  

Science.gov (United States)

The amount of impervious surface in a watershed is a landscape indicator integrating a number of concurrent interactions that influence a watershed's hydrology. Remote sensing data and techniques are viable tools to assess anthropogenic impervious surfaces. However a fundamental ...

11

to characterize the impervious water storage with an urban surface-flux parameterization TERRA-MLU: evaluation and calibration for Toulouse city  

Science.gov (United States)

Evaporation from the urban impervious surface could have a considerable impact on the surface energy and moisture balance on rainy days. In particular, the ever increasing urbanization could alter the interaction between evaporation from the surface and precipitation within the urban climate (change) in the future. However, uncertainty exists within the determination of water storage parameters for the impervious surface, and hydrological parameters of the soil for the natural fraction in urban environments. In order to investigate the water balance over urban areas in more detail, TERRA-MLU, a new urban surface-flux parameterization, is applied over Toulouse city centre during the CAPITOUL campaign during 2004. The new urban parameterization covers a direct implementation of urban characteristics in TERRA_ML, Soil-Vegetation-Atmosphere Transfer model of COSMO. Besides anthropogenic heat, specific dynamic, radiative and thermal parameters including roughness length, heat capacity, conductivity, albedo and emissivity are assigned for the urban land-cover. A bluff-roughness thermal roughness length parametrization is used. New surface-layer transfer coefficients are adopted which can deal with very small thermal roughness lengths typical for urban surfaces. An new impervious water storage parameterization is introduced as well. TERRA-MLU is evaluated 'offline' for Marseille, Toulouse, Basel and Vancouver. Sensitivity analysis at the Toulouse site demonstrates that the maximum impervious water storage needs to be equal or less than 1kg/m2 if one only considers evaporation at a potential rate from the impervious surface. Furthermore, results are improved by implementing a storage form parameter that accounts for the reduction of evaporative surface fraction in case of small water content on the impervious surface. An offline sensitivity analysis is performed to estimate the maximum water storage and the storage form parameter. At last, it is found that the rooting depth of the vegetation needs to be described carefully in urban environments with large trees in order not to underestimate the latent heat during summer.

Wouters, Hendrik; Demuzere, Matthias; De Ridder, Koen; van Lipzig, Nicole; Vogel, Gerd

2013-04-01

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Detection of impervious surface change with multitemporal Landsat images in an urban-rural frontier  

Science.gov (United States)

Mapping and monitoring impervious surface dynamic change in a complex urban-rural frontier with medium or coarse spatial resolution images is a challenge due to the mixed pixel problem and the spectral confusion between impervious surfaces and other non-vegetation land covers. This research selected Lucas do Rio Verde County in Mato Grosso State, Brazil as a case study to improve impervious surface estimation performance by the integrated use of Landsat and QuickBird images and to monitor impervious surface change by analyzing the normalized multitemporal Landsat-derived fractional impervious surfaces. This research demonstrates the importance of two-step calibrations. The first step is to calibrate the Landsat-derived fraction impervious surface values through the established regression model based on the QuickBird-derived impervious surface image in 2008. The second step is to conduct the normalization between the calibrated 2008 impervious surface image with other dates of impervious surface images. This research indicates that the per-pixel based method overestimates the impervious surface area in the urban-rural frontier by 50%-60%. In order to accurately estimate impervious surface area, it is necessary to map the fractional impervious surface image and further calibrate the estimates with high spatial resolution images. Also normalization of the multitemporal fractional impervious surface images is needed to reduce the impacts from different environmental conditions, in order to effectively detect the impervious surface dynamic change in a complex urban-rural frontier. The procedure developed in this paper for mapping and monitoring impervious surface area is especially valuable in urban-rural frontiers where multitemporal Landsat images are difficult to be used for accurately extracting impervious surface features based on traditional per-pixel based classification methods as they cannot effectively handle the mixed pixel problem.

Lu, Dengsheng; Moran, Emilio; Hetrick, Scott

13

Global Distribution and Density of Constructed Impervious Surfaces  

Directory of Open Access Journals (Sweden)

Full Text Available We present the first global inventory of the spatial distribution and density ofconstructed impervious surface area (ISA. Examples of ISA include roads, parking lots,buildings, driveways, sidewalks and other manmade surfaces. While high spatialresolution is required to observe these features, the new product reports the estimateddensity of ISA on a one-km2 grid based on two coarse resolution indicators of ISA – thebrightness of satellite observed nighttime lights and population count. The model wascalibrated using 30-meter resolution ISA of the USA from the U.S. Geological Survey.Nominally the product is for the years 2000-01 since both the nighttime lights andreference data are from those two years. We found that 1.05% of the United States landarea is impervious surface (83,337 km2 and 0.43 % of the world’s land surface (579,703km2 is constructed impervious surface. China has more ISA than any other country(87,182 km2, but has only 67 m2 of ISA per person, compared to 297 m2 per person in theUSA. The distribution of ISA in the world’s primary drainage basins indicates that watersheds damaged by ISA are primarily concentrated in the USA, Europe, Japan, China and India. The authors believe the next step for improving the product is to include reference ISA data from many more areas around the world.

Ramakrishna Nemani

2007-09-01

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Global Distribution and Density of Constructed Impervious Surfaces  

Science.gov (United States)

We present the first global inventory of the spatial distribution and density of constructed impervious surface area (ISA). Examples of ISA include roads, parking lots, buildings, driveways, sidewalks and other manmade surfaces. While high spatial resolution is required to observe these features, the new product reports the estimated density of ISA on a one-km2 grid based on two coarse resolution indicators of ISA the brightness of satellite observed nighttime lights and population count. The model was calibrated using 30-meter resolution ISA of the USA from the U.S. Geological Survey. Nominally the product is for the years 2000-01 since both the nighttime lights and reference data are from those two years. We found that 1.05% of the United States land area is impervious surface (83,337 km2) and 0.43 % of the world's land surface (579,703 km2) is constructed impervious surface. China has more ISA than any other country (87,182 km2), but has only 67 m2 of ISA per person, compared to 297 m2 per person in the USA. The distribution of ISA in the world's primary drainage basins indicates that watersheds damaged by ISA are primarily concentrated in the USA, Europe, Japan, China and India. The authors believe the next step for improving the product is to include reference ISA data from many more areas around the world.

Elvidge, Christopher D.; Tuttle, Benjamin T.; Sutton, Paul S.; Baugh, Kimberly E.; Howard, Ara T.; Milesi, Cristina; Bhaduri, Budhendra L.; Nemani, Ramakrishna

2007-01-01

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Impact of Impervious Surface on River Discharge in Lake Kasumigaura Basin, Japan  

Science.gov (United States)

Impervious Surface Area (ISA) is defined as the constructed surface that prevents water from infiltrating into the soil. The ISA has emerged not only as an indicator of the degree of urbanization, but also as a major indicator of environmental quality for drainage basin management. This study focused on the relation between ISA ratio calculated by remote sensing technology and river discharge in Lake Kasumigaura Basin, Japan. ISA ratio was estimated by satellite image using Prescreened and Normalized Multiple Endmember Spectral Mixture Analysis (PNMESMA) developed for drainage basin with the estimating error smaller than 10%. Three types (vegetation, impervious surface, soil) of endmember were selected from the image, and the fraction of each endmember was calculated based on linear mixing model. River discharge dataset was collected from Kasumigaura River Office. Since the monitoring sites do not locate in the down stream, the up stream river basins of the monitoring sites were extracted by hydrological model in Geographic Information System (GIS) instead of the existing basin map. Digital Elevation Model (DEM) data with spatial resolution of 10m was collected from Geospatial Information Authority of Japan (GSI) to estimate the area of drainage. For the extracted drainage basins, the statistical relation between ISA ratio and river discharge were studied in 2000 and 2007 since the Landsat images used to estimate the fraction of ISA were in good image quality. The long-term change of river discharge was also investigated to provide the background value of this research. Results of spatial analysis suggested that the increase of the ISA raised the discharge in the rainy season, and reduced the discharge in the period of water shortage in Lake Kasumigaura Basin.

Yang, F.; Matsushita, B.; Fukushima, T.; Lab of Environmental Modeling; Creation

2011-12-01

16

Detection of impervious surface change with multitemporal Landsat images in an urban-rural frontier  

OpenAIRE

Mapping and monitoring impervious surface dynamic change in a complex urban-rural frontier with medium or coarse spatial resolution images is a challenge due to the mixed pixel problem and the spectral confusion between impervious surfaces and other non-vegetation land covers. This research selected Lucas do Rio Verde County in Mato Grosso State, Brazil as a case study to improve impervious surface estimation performance by the integrated use of Landsat and QuickBird images and to monitor imp...

Lu, Dengsheng; Moran, Emilio; Hetrick, Scott

2011-01-01

17

Comparing Urban Impervious Surface Identification Using Landsat and High Resolution Aerial Photography  

OpenAIRE

This paper evaluates accuracies of selected image classification strategies, as applied to Landsat imagery to assess urban impervious surfaces by comparing them to reference data manually delineated from high-resolution aerial photos. Our goal is to identify the most effective methods for delineating urban impervious surfaces using Landsat imagery, thereby guiding applications for selecting cost-effective delineation techniques. A high-resolution aerial photo was used to delineate impervious ...

Campbell, James B.; Parece, Tammy E.

2013-01-01

18

Effects of spatial resolution of remotely sensed data on estimating urban impervious surfaces.  

Science.gov (United States)

Impervious surfaces are the result of urbanization that can be explicitly quantified, managed and controlled at each stage of land development. It is a very useful environmental indicator that can be used to measure the impacts of urbanization on surface runoff, water quality, air quality, biodiversity and microclimate. Therefore, accurate estimation of impervious surfaces is critical for urban environmental monitoring, land management, decision-making and urban planning. Many approaches have been developed to estimate surface imperviousness, using remotely sensed data with various spatial resolutions. However, few studies, have investigated the effects of spatial resolution on estimating surface imperviousness. We compare medium-resolution Landsat data with high-resolution SPOT images to quantify the imperviousness in Beijing, China. The results indicated that the overall 91% accuracy of estimates of imperviousness based on TM data was considerably higher than the 81% accuracy of the SPOT data. The higher resolution SPOT data did not always predict the imperviousness of the land better than the TM data. At the whole city level, the TM data better predicts the percentage cover of impervious surfaces. At the sub-city level, however, the ring belts from the central core to the urban-rural peripheral, the SPOT data may better predict the imperviousness. These results highlighted the need to combine multiple resolution data to quantify the percentage of imperviousness, as higher resolution data do not necessarily lead to more accurate estimates. The methodology and results in this study can be utilized to identify the most suitable remote sensing data to quickly and efficiently extract the pattern of the impervious land, which could provide the base for further study on many related urban environmental problems. PMID:22128546

Li, Weifeng; Ouyang, Zhiyun; Zhou, Weiqi; Chen, Qiuwen

2011-01-01

19

Procedure to detect impervious surfaces using satellite images and light detection and ranging (lidar) data  

Science.gov (United States)

The detection of impervious surfaces is an important issue in the study of urban and rural environments. Imperviousness refers to water's inability to pass through a surface. Although impervious surfaces represent a small percentage of the Earth's surface, knowledge of their locations is relevant to planning and managing human activities. Impervious structures are primarily manmade (e.g., roads and rooftops). Impervious surfaces are an environmental concern because many processes that modify the normal function of land, air, and water resources are initiated during their construction. This paper presents a novel method of identifying impervious surfaces using satellite images and light detection and ranging (LIDAR) data. The inputs for the procedure are SPOT images formed by four spectral bands (corresponding to red, green, near-infrared and mid-infrared wavelengths), a digital terrain model, and an .las file. The proposed method computes five decision indexes from the input data to classify the studied area into two categories: impervious (subdivided into buildings and roads) and non-impervious surfaces. The impervious class is divided into two subclasses because the elements forming this category (mainly roads and rooftops) have different spectral and height properties, and it is difficult to combine these elements into one group. The classification is conducted using a decision tree procedure. For every decision index, a threshold is set for which every surface is considered impervious or non-impervious. The proposed method has been applied to four different regions located in the north, center, and south of Spain, providing satisfactory results for every dataset.

Rodrguez-Cuenca, B.; Alonso-Rodrguez, M. C.; Domenech-Tofio, E.; Valcrcel Sanz, N.; Delgado-Hernndez, J.; Peces-Morera, Juan Jos; Arozarena-Villar, Antonio

2014-10-01

20

Improving Distributed Runoff Prediction in Urbanized Catchments with Remote Sensing based Estimates of Impervious Surface Cover  

Science.gov (United States)

The amount and intensity of runoff on catchment scale are strongly determined by the presence of impervious land-cover types, which are the predominant cover types in urbanized areas. This paper examines the impact of different methods for estimating impervious surface cover on the prediction of peak discharges, as determined by a fully distributed rainfall-runoff model (WetSpa), for the upper part of the Woluwe River catchment in the southeastern part of Brussels. The study shows that detailed information on the spatial distribution of impervious surfaces, as obtained from remotely sensed data, produces substantially different estimates of peak discharges than traditional approaches based on expert judgment of average imperviousness for different types of urban land use. The study also demonstrates that sub-pixel estimation of imperviousness may be a useful alternative for more expensive high-resolution mapping for rainfall-runoff modelling at catchment scale.

Chormanski, Jaroslaw; Van de Voorde, Tim; De Roeck, Tim; Batelaan, Okke; Canters, Frank

2008-01-01

21

Mapping and Assessing Urban Impervious Areas Using Multiple Endmember Spectral Mixture Analysis: A Case Study in the City of Tampa, Florida  

Science.gov (United States)

The advance in remote sensing technology helps people more easily assess urban growth. In this study, the utility of multiple endmember spectral mixture analysis (MESMA) is examined in a sub-pixel analysis of Landsat Thematic Mapper (TM) imagery to map urban physical components in Tampa, FL. The three physical components of urban land cover (LC): impervious surface, vegetation and soil, were compared using the proposed MESMA with a traditional spectral mixture analysis (SMA). MESMA decomposes each pixel to address the heterogeneity of urban LC characteristic by allowing the number and types of endmembers to vary on a per pixel basis. This study generated 642 spectral mixture models of 2-, 3-, and 4-endmembers for each pixel to estimate the fractions of impervious surface, vegetation, soil, and shade in the study area with a constraint of lowest root mean square error (RMSE). A comparative analysis of the impervious surface areas (ISA) mapped with MESMA and SMA demonstrated that MESMA produced more accurate results of mapping urban physical components than those by SMA. With the multiyear Landsat TM data, we quantified sub-pixel %ISA and the %ISA changes to assess urban growth in the City of Tampa, Florida during the past twenty years. The experimental results demonstrate that the MESMA approach is effective in mapping and monitoring urban land use/land cover changes using moderate-resolution multispectral imagery at a sub-pixel level.

Weng, Fenqing

22

An Integrated Method for Mapping Impervious and Pervious Areas in Urban Environments Using Hyperspectral and LiDAR Data  

Science.gov (United States)

As urbanization continues to increase and extreme climatic events become more prevalent, urban planners and engineers are actively implementing adaptive measures to protect urban assets and communities. To support the urban planning adaptation process, mapping of impervious and pervious areas is essential to understanding the hydrodynamic environment within urban areas for flood risk planning. The application of advance geospatial data and analytical techniques using remote sensing and GIS can improve land surface characterization to better quantify surface run-off and infiltration. This study presents a method to combine airborne hyperspectral and LiDAR data for classifying pervious (e.g. vegetation, gravel, and soil) and impervious (e.g. asphalt and concrete) areas within road allowance areas for the City of Surrey, British Columbia, Canada. Hyperspectral data was acquired using the Compact Airborne Spectrographic Imager (CASI) at 1 m ground spatial resolution, consisting of 72 spectral bands, and LiDAR data acquired from Leica Airborne LiDAR system at a density of 20 points/m2. A spectral library was established using 10 cm orthophotography and GIS data to identify surface features. In addition to spectral functions such as mean and standard deviation, several spectral indices were developed to discriminate between asphalt, concrete, gravel, vegetation, and shadows respectively. A spectral analysis of selected endmembers was conducted and an initial classification technique was applied using Spectral Angle Mapper (SAM). The classification results (i.e. shadows) were improved by integrating LIDAR data with the hyperspectral data.

Hashemi Beni, L.; McArdle, S.; Khayer, Y.

2014-11-01

23

ACCURACY ASSESSMENT OF THE NATIONAL LAND COVER DATABASE 2001 (NLCD 2001) IMPERVIOUSNESS DATA  

Science.gov (United States)

Landscape conditions of watersheds strongly influence the sustainability of aquatic resources valued by society, including quality of drinking water, diversity of stream life, and resilience to catastrophic flooding. The amount of impervious surface area in a watershed is a key ...

24

Extraction of urban impervious surface information based on object-oriented technology  

Science.gov (United States)

Impervious surface is an important part of urban underlying surface, as well as an important monitoring index for city ecological system and environment changes. However, accurate impervious surface extraction is still a challenge. This paper uses the color, shape and overall heterogeneity features from the high spatial resolution remote sensing image to extract the impervious surface. An edge-based image segmentation algorithm is put forward to fuse heterogeneous objects which integrates edge features and multi-scale segmentation algorithm and uses the edge information to guide image objects generation. Results showed that this method can greatly improve the accuracy of image segmentation. Accuracy assessment indicated that the overall impervious surface classification accuracy and a Kappa coefficient yield 87% and 0.84, respectively.

Liu, Aixia; Zhao, Xiaojie; Wang, Jing; He, Ting

2013-10-01

25

Improving Distributed Runoff Prediction in Urbanized Catchments with Remote Sensing based Estimates of Impervious Surface Cover  

Directory of Open Access Journals (Sweden)

Full Text Available The amount and intensity of runoff on catchment scale are strongly determinedby the presence of impervious land-cover types, which are the predominant cover types inurbanized areas. This paper examines the impact of different methods for estimatingimpervious surface cover on the prediction of peak discharges, as determined by a fullydistributed rainfall-runoff model (WetSpa, for the upper part of the Woluwe Rivercatchment in the southeastern part of Brussels. The study shows that detailed informationon the spatial distribution of impervious surfaces, as obtained from remotely sensed data,produces substantially different estimates of peak discharges than traditional approachesbased on expert judgment of average imperviousness for different types of urban land use.The study also demonstrates that sub-pixel estimation of imperviousness may be a usefulalternative for more expensive high-resolution mapping for rainfall-runoff modelling atcatchment scale.

Frank Canters

2008-02-01

26

[Comparison of performances in retrieving impervious surface between hyperspectral (Hyperion) and multispectral (TM/ETM+) images].  

Science.gov (United States)

The retrieval of impervious surface is a hot topic in the remote sensing field in the past decade. Nevertheless, studies on retrieving impervious surface from hyperspectral image and the comparison of the performances in retrieving impervious surface between hyperspectral and multispectral images are rarely reported. Therefore, The present paper focuses on the characteristics of hyperspectral (EO-1 Hyperion) and multispectral (Landsat TM/ETM+) images and implements a complementary study on the comparison based on the retrieved impervious surface information between Hyperion and TM/ETM+ data. For up to 242 bands of Hyperion image, a further study was carried out to select feature bands for impervious surface retrieving using stepwise discriminant analysis. As a result, 11 feature bands were selected and a new image named Hyperion' was thus composed. The new Hyperion' image was used to investigate whether this band-reduced image could obtain higher accuracy in retrieving impervious surface. The three test regions were selected from Fuzhou, Guangzhou and Hangzhou of China, with date-coincident or nearly coincident image pairs of the used sensors. The linear spectral mixture analysis (LSMA) was employed to retrieve impervious surface and the results were accessed for their accuracy. The comparison shows that the Hyperion image has higher accuracy than TM/ETM+, and the Hyperion' composed of the selected 11 feature bands has the highest accuracy. The advantages of Hyperion in spectral and radiometric resolutions over TM/ETM+ are believed to be the main factors contributing to the higher accuracy. The high spectral and radiometric resolutions of Hyperion image allow the sensor to have higher sensitivity in distinguishing subtle spectral changes of ground objects. While, the highest accuracy the 11-band Hyperion' image achieved is owing to the significant reduction of the band dimension of the image and thus the band redundancy. PMID:25007632

Tang, Fei; Xu, Han-Qiu

2014-04-01

27

Synergistic using medium-resolution and high-resolution remote sensing imagery to extract impervious surface for Dianci Basin  

Science.gov (United States)

The knowledge of impervious surfaces, especially the magnitude, location, geometry, spatial pattern of impervious surfaces, is significant to urban ecosystem studies, including urban hydrology, urban climate, land use planning and resource management.Impervious surface area (ISA) is considered a key indicator of environmental quality and can be used to address complex urban environmental issues, particularly those related to the health of urban watersheds. ISA is also an indicator of non-point source pollution or polluted runoff. Remote sensing offers a consistent framework for representing spatial patterns and rates of urbanization over time through accurate observations of impervious surface area. Most of the existing methods of extracting impervious surface based on remote sensing concentrate on an urban scale, but the rapid and accurate methods of extracting impervious surfaces in a basin scale are nearly nonexistent in China and abroad. In recent years,with the rapid urbanization especially surrounding the Dianchi water body, the impervious surface coverage rate also grows rapidly and results in severe degradation of basin water environment within Dianchi watershed. In this study, we developed an approach to extract impervious surface for Dianci Basin by synergistic using medium-resolution and high-resolution remote sensing imagery. Subpixel percent impervious surfaces at Thematic Mapper (TM) images were mapped using the classification and regression tree(CART) algorithm. Sub-pixel impervious surfaces at 30m resolution were mapped in this study area through regression tree models. The estimated ISA results were evaluated through independent ISA reference data derived from high resolution QuickBird. The results prove the suitability of the approach for a widely automated and mapping of impervious surfaces in a basin scale.

Hong, Liang; Yang, Kun; Deng, Ming; Liu, Cun

2014-03-01

28

Mapping Impervious Surfaces Globally at 30m Resolution Using Landsat Global Land Survey Data  

Science.gov (United States)

Impervious surfaces, mainly artificial structures and roads, cover less than 1% of the world's land surface (1.3% over USA). Regardless of the relatively small coverage, impervious surfaces have a significant impact on the environment. They are the main source of the urban heat island effect, and affect not only the energy balance, but also hydrology and carbon cycling, and both land and aquatic ecosystem services. In the last several decades, the pace of converting natural land surface to impervious surfaces has increased. Quantitatively monitoring the growth of impervious surface expansion and associated urbanization has become a priority topic across both the physical and social sciences. The recent availability of consistent, global scale data sets at 30m resolution such as the Global Land Survey from the Landsat satellites provides an unprecedented opportunity to map global impervious cover and urbanization at this resolution for the first time, with unprecedented detail and accuracy. Moreover, the spatial resolution of Landsat is absolutely essential to accurately resolve urban targets such a buildings, roads and parking lots. With long term GLS data now available for the 1975, 1990, 2000, 2005 and 2010 time periods, the land cover/use changes due to urbanization can now be quantified at this spatial scale as well. In the Global Land Survey - Imperviousness Mapping Project (GLS-IMP), we are producing the first global 30 m spatial resolution impervious cover data set. We have processed the GLS 2010 data set to surface reflectance (8500+ TM and ETM+ scenes) and are using a supervised classification method using a regression tree to produce continental scale impervious cover data sets. A very large set of accurate training samples is the key to the supervised classifications and is being derived through the interpretation of high spatial resolution (~2 m or less) commercial satellite data (Quickbird and Worldview2) available to us through the unclassified archive of the National Geospatial Intelligence Agency (NGA). For each continental area several million training pixels are derived by analysts using image segmentation algorithms and tools and then aggregated to the 30m resolution of Landsat. Here we will discuss the production/testing of this massive data set for Europe, North and South America and Africa, including assessments of the 2010 surface reflectance data. This type of analysis is only possible because of the availability of long term 30m data sets from GLS and shows much promise for integration of Landsat 8 data in the future.

Brown de Colstoun, E.; Huang, C.; Wolfe, R. E.; Tan, B.; Tilton, J.; Smith, S.; Phillips, J.; Wang, P.; Ling, P.; Zhan, J.; Xu, X.; Taylor, M. P.

2013-12-01

29

Urban percent impervious surface and its relationship with land surface temperature in Yantai City, China  

Science.gov (United States)

This study investigated percent impervious surface area (PISA) extracted by a four-endmember normalized spectral mixture analysis (NSMA) method and evaluated the reliability of PISA as an indicator of land surface temperature (LST). Landsat Thematic Mapper (TM) and Enhanced Thematic Mapper Plus (ETM+) images for Yantai city, eastern China obtained from USGS were used as the main data source. The results demonstrated that four-endmember NSMA method performed better than the typical three-endmember one, and there was a strong linear relationship between LST and PISA for the two images, which suggest percent impervious surface area provides an alternative parameter for analyzing LST quantitatively in urban areas.

Yu, Xinyang; Lu, Changhe

2014-03-01

30

Commonality of rainfall variables influencing suspended solids concentrations in storm runoff from three different urban impervious surfaces  

Science.gov (United States)

Finding a common set of rainfall variables to explain the concentration of suspended solids in runoff from typical urban impervious surfaces has many applications in stormwater planning. This paper describes a statistical process to identify key explanatory variables to non-coarse particle (suspended solids roof surfaces located in Toowoomba, Australia. The dominant variables for all surfaces were rainfall depth and peak 6-min rainfall intensity. Storm duration, defined as the time period when rainfall intensity exceeds 0.25 mm/h and antecedent storm rainfall were also important predictors, but was less dominant. The regression model fitted to non-coarse particle concentration across all surfaces was proportional to rainfall depth raised to a negative power and peak 6-min rainfall intensity raised to a positive power; the proportionality constant varies by surface type. The form of this common model has a physical basis and is analogous to the modified universal soil loss equation widely used for soil loss estimation for non-urban areas.

Brodie, Ian M.; Dunn, Peter K.

2010-06-01

31

Impervious Surface Area Mapping using Landsat Imagery: Applications to Hydrology and Land Use Change Monitoring  

Science.gov (United States)

Impervious surfaces include rooftops, roads, parking lots and other areas that are impermeable to moisture. As the amount of built environment around urban areas has increased, it has been widely recognized that more impervious surface area (ISA) results in greater volume and intensity of stream flow, which can degrade stream health and require expensive modifications to flood control structures. Other effects include increased urban "heat island" influences and changes in local weather. If impervious areas could be accurately mapped using satellite imagery, it would provide valuable input to many applications, from hydrologic modeling to land use planning. We have developed a method to map subpixel ISA with Landsat Thematic Mapper (TM) imagery and classification - regression tree algorithms. This approach provides highly accurate (90+ percent) maps of ISA, but also permits estimation of the proportion of each cell occupied by impervious materials (between 0-100 percent). We report on a recently completed a map of ISA for the entire 163,000 km2 Chesapeake Bay watershed, a region of highly altered land cover and rapid land use change. We also report on the mapping of change patterns, indicated by ISA changes between 1986 - 2001, in an 18,000 km2 area centered on Baltimore - Washington, D.C. We review the methods, issues, technical challenges, results, accuracy, and advantages of this approach, and provide an overview of various applications for which the products are currently being used.

Smith, A.; Goetz, S. J.; Mazzacato, M. E.; Jantz, C.; Wright, R.

2002-12-01

32

Comparing Urban Impervious Surface Identification Using Landsat and High Resolution Aerial Photography  

Directory of Open Access Journals (Sweden)

Full Text Available This paper evaluates accuracies of selected image classification strategies, as applied to Landsat imagery to assess urban impervious surfaces by comparing them to reference data manually delineated from high-resolution aerial photos. Our goal is to identify the most effective methods for delineating urban impervious surfaces using Landsat imagery, thereby guiding applications for selecting cost-effective delineation techniques. A high-resolution aerial photo was used to delineate impervious surfaces for selected census tracts for the City of Roanoke, Virginia. National Land Cover Database Impervious Surface data provided an overall accuracy benchmark at the city scale which was used to assess the Landsat classifications. Three different classification methods using three different band combinations provided overall accuracies in excess of 70% for the entire city. However, there were substantial variations in accuracy when the results were subdivided by census tract. No single classification method was found most effective across all census tracts; the best method for a specific tract depended on method, band combination, and physical characteristics of the area. These results highlight impacts of inherent local variability upon attempts to characterize physical structures of urban regions using a single metric, and the value of analysis at finer spatial scales.

James B. Campbell

2013-10-01

33

Imperviousness of the hydrophobic silica aerogels against various solvents and acids  

Science.gov (United States)

The experimental results on the imperviousness of the silica aerogels against various organic solvents and acids, are reported. Various types of hydrophobic silica aerogels were prepared using methyltrimethoxysilane (MTMS); tetraethoxysilane (TEOS) with ethyltriethoxysilane (ETES) and phenyltriethoxysilane (PTES) as co-precursors. The organic solvents used were: methanol, ethanol and acetone, and the acids used were: hydrochloric acid (HCl), nitric acid (HNO 3) and sulphuric acid (H 2SO 4). The imperviousness of the aerogels against these solvents and acids were tested with the variation of the percentage of organic solvents and acids in water from 10 to 100% and was characterized by the contact angle measurements. It was observed that in all the cases, the contact angle decreased with an increase in the percentage of solvent in water. While there was no absorption of the solvent up to 20% in water by the ETES and PTES modified aerogels, the MTMS-based aerogels showed the imperviousness up to 60% of the solvent in water. The MTMS aerogels were also impervious against all the three acids up to 100%, while the ETES and PTES modified aerogels could withstand only up to 80% of acids in water.

Venkateswara Rao, A.; Hegde, Nagaraja D.; Shewale, Poonam M.

2007-02-01

34

Object-Oriented Classification to Map Impervious Surfaces for Hydrologic Models 1956  

Science.gov (United States)

Urban growth in the southwestern U.S. influences strongly storm water runoff by creating impervious surfaces. Hydrologic models used to compute runoff from watersheds require an estimate of the area and location of pervious surfaces as input data. In semi-arid regions, this information is provided c...

35

Mapping impervious surfaces using object-oriented classification in a semiarid urban region  

Science.gov (United States)

Mapping the expansion of impervious surfaces in urbanizing areas is important for monitoring and understanding the hydrologic impacts of land development. The most common approach using spectral vegetation indices, however, is difficult in arid and semiarid environments where vegetation is sparse an...

36

Crucible cast from beryllium oxide and refractory cement is impervious to flux and molten metal  

Science.gov (United States)

Crucible from a mixture of a beryllium oxide aggregate and hydraulic refractory cement, and coated with an impervious refractory oxide will not deteriorate in the presence of fused salt- molten metal mixtures such as uranium- magnesium-zinc-halide salt systems. Vessels cast by this process are used in the flux reduction of oxides of thorium and uranium.

Jastrzebski, Z. D.

1966-01-01

37

Updating the 2001 National Land Cover Database Impervious Surface Products to 2006 using Landsat Imagery Change Detection Methods  

Science.gov (United States)

A prototype method was developed to update the U.S. Geological Survey (USGS) National Land Cover Database (NLCD) 2001 to a nominal date of 2006. NLCD 2001 is widely used as a baseline for national land cover and impervious cover conditions. To enable the updating of this database in an optimal manner, methods are designed to be accomplished by individual Landsat scene. Using conservative change thresholds based on land cover classes, areas of change and no-change were segregated from change vectors calculated from normalized Landsat scenes from 2001 and 2006. By sampling from NLCD 2001 impervious surface in unchanged areas, impervious surface predictions were estimated for changed areas within an urban extent defined by a companion land cover classification. Methods were developed and tested for national application across six study sites containing a variety of urban impervious surface. Results show the vast majority of impervious surface change associated with urban development was captured, with overall RMSE from 6.86 to 13.12% for these areas. Changes of urban development density were also evaluated by characterizing the categories of change by percentile for impervious surface. This prototype method provides a relatively low cost, flexible approach to generate updated impervious surface using NLCD 2001 as the baseline. ?? 2010 Elsevier Inc.

Xian, G.; Homer, C.

2010-01-01

38

Subsoil Compaction: A hidden form of Soil Sealing in Europe  

OpenAIRE

There are two definitions of soil sealing: (I) covering (sealing) the soil surface by impervious materials, e.g. concrete, metal, glass, tarmac and plastic; and (II) changing the nature of the soil such that it behaves as an impermeable medium, e.g. by compaction. The main causes of soil sealing according to the first definition (I) are building development (e.g. industrial and residential premises) and transport (e.g. roads). Changing the nature of the soil s...

Jones, Robert J. A.; Montanarella, Luca

2001-01-01

39

Evaluation of land ecological environment in Zhoushan Islands by remotely sensed impervious surfaces  

Science.gov (United States)

Coastal islands are located in a transitional environment where land and ocean interact. During the past 20 years, large areas of the natural landscape of Zhoushan islands have been replaced by human features. There is limited research detailing the amount of impervious surface growth in the Zhoushan islands and trends in the land environment using remotely sensed technologies. The purpose of this paper is to assess the influences of anthropogenic activities on land ecological environment in Zhoushan islands based on remotely sensed impervious surfaces. First the impervious surfaces information of 1986, 1995 and 2006 were estimated using Landsat Thematic Mapper (TM) images, and then an integrated state indicator was built. The results reveal that imperious surfaces areas (ISA) of Zhoushan islands remarkably increased from 19.2 km2 (2.73%) in 1986 to 29.5 km2 (4.20%) in 1995, and to 58.2 km2 (8.27%) in 2006. The average state value for the total area was 0.70, 0.65, and 0.55 respectively for 1986, 1995, and 2006. Of the surrounding islands, the Lujiazhi, Xiaogan, Panzhi, and Cezi suffered the most land disturbance intensity from human activities, followed by the Jintang, Xiushan, and Damao, and the Changbai and Changzhi had the lowest disturbance values. It indicates that the land ecological environment of Zhoushan islands was variously disturbed by growing human activities over time. Further, we found that the topography, island size, spatial location from Zhoushan Island and economic policy had an influence on change of impervious surfaces for each island.

Zhang, Xiaoping; Pan, Delu; Chen, Jianyu; Chen, Peng; Jia, Yonghong

2013-10-01

40

Improving Distributed Runoff Prediction in Urbanized Catchments with Remote Sensing based Estimates of Impervious Surface Cover  

OpenAIRE

The amount and intensity of runoff on catchment scale are strongly determinedby the presence of impervious land-cover types, which are the predominant cover types inurbanized areas. This paper examines the impact of different methods for estimatingimpervious surface cover on the prediction of peak discharges, as determined by a fullydistributed rainfall-runoff model (WetSpa), for the upper part of the Woluwe Rivercatchment in the southeastern part of Brussels. The study shows that detailed in...

Frank Canters; Okke Batelaan; Tim De Roeck; Tim Van de Voorde; Jaroslaw Chormanski

2008-01-01

41

Influence of Vegetation, Impervious Surface and Water Body on Land Thermal Fileld of Karst City  

Directory of Open Access Journals (Sweden)

Full Text Available In order to evaluate the impact of karst Guilin City rapid expansion on urban heat island effect, land surface temperature (LST, seven vegetation indexes (VI, percent impervious surface area (ISA and modified normalized difference water index (MNDWI were retrieved with model from TM image. After the influcence of temporal and spatial variation of vegetation, impervious surface and water body on land thermal field of karst city was studied. Results show that there is a significant negative linear relationship between LST and VI, so is between LST and MNDWI. Howerver, the relationship between LST and ISA shows significant positive linear. From 1989 to 2006, the medium and high vegetation covered area of NDVI>0.4 slashes from 76.89% to 32.65%, and the area without vegetation coverage of NDVI0.9 rises greatly from 12.1% to 32.1%.Those result in the high and sub-high surafce temperature areas rises from 7.9% to 15.9%, the low and sub-low surafce temperature areas drop substantially from 61.8% to 38.9%. Urban heat island effect markedly enhanced. Continuous large impervious surface area is one of the main factors contributing to urban heat island on karst city. But Vegetation on karst hills, urban forest and large water bodies such as rivers and lakes have very great impact on karst urban thermal environment and mitigate urban heat island.

HU Dao-sheng

2014-05-01

42

Importance of High-Resolution LiDAR Data in Modeling Runoff Levels Over Impervious Surfaces  

Science.gov (United States)

Directly connected impervious areas collect and deliver unfiltered runoff to modified and impacted waterways. Modeling water flow over the landscape is an effective method of observing drainage patterns and predicting pollutant and sediment loadings. Improved models applying high-resolution elevation data can identify key areas with high pollutant output. This is a crucial issue in the Lake Tahoe Basin where lakeshore urban development has increased and lake clarity has been declining for years. This study aims to evaluate an integrated LiDAR and GIS-based modeling approach that uses a fine-scaled ground surface and impervious surface connectivity to predict the pollutant load in the Lake Tahoe Basin This study produced a fine-scaled surface model of nine subset catchments in the South Tahoe basin, including areas of low (below 20%), medium (30% to 50%) and high (above 50%) impervious surface cover. Our method integrated LiDAR, multispectral imagery, and GIS data to develop accurate terrain models, hydrologic routing, and directly connected impervious area layers for the Lake Tahoe basin. The high-density ground and object elevation data collected using Light Detection and Ranging (LiDAR) creates an accurate picture of water flow over the land, and obstacles to the flow such as buildings. High-resolution LiDAR data was obtained from the Round 10 Lake Tahoe Southern Nevada Public Land Management capital program from the year 2010. This data was processed to create a digital elevation model of the ground surface. Land use classification used object height information from the LiDAR cloud, NAIP 4-band images with 1-meter resolution and a normalized difference vegetation index image derived from the NAIP imagery. The US Army Core of Engineers hydrologic modeling system (HEC-HMS) will be used to model runoff. Based on long-term simulations the effect of directly connected impervious area on rainfall-runoff characteristics for the South Lake Tahoe catchments will be evaluated. Similar scenarios will be run on data derived from 10-meter resolution USGS elevation models. Regression analyses will be used to compare the simulation results derived using LiDAR data inputs to the results obtained using lower-resolution USGS elevation models and to observed monitoring data.

Melosh, C.; Rao, M.

2013-12-01

43

Ecologically relevant geomorphic attributes of streams are impaired by even low levels of watershed effective imperviousness  

Science.gov (United States)

Urbanization almost inevitably results in changes to stream morphology. Understanding the mechanisms for such impacts is a prerequisite to minimizing stream degradation and achieving restoration goals. However, investigations of urban-induced changes to stream morphology typically use indicators of watershed urbanization that may not adequately represent degrading mechanisms and commonly focus on geomorphic attributes such as channel dimensions that may be of little significance to the ecological goals for restoration. We address these shortcomings by testing if a measure characterizing urban stormwater drainage system connections to streams (effective imperviousness, EI) is a better predictor of change to ecologically relevant geomorphic attributes than a more general measure of urban density (total imperviousness, TI). We test this for 17 sites in independent watersheds across a gradient of urbanization. We found that EI was a better predictor of all geomorphic variables tested than was TI. Bank instability was positively correlated with EI, while width/depth (a measure of channel incision), bedload sediment depth, and frequency of bars, benches, and large wood were negatively correlated. Large changes in all geomorphic variables were detected at very low levels of EI (Urbanization influences stream morphology more than any other land use (Douglas, 2011): it alters hydrology and sediment inputs leading to deepening and widening of streams (Chin, 2006). Concomitantly, urbanization often directly impairs stream morphology through channel and riparian zone interventions, e.g., culverts (Hawley et al., 2012), rock protection (Vietz et al., 2012b), and constricted floodplains (Gurnell et al., 2007). These changes to channel geomorphology in turn contribute to poor in-stream ecological condition (Morley and Karr, 2002; Walsh et al., 2005b; Gurnell et al., 2007; Elosegi et al., 2010).The common conception is that channels undergo gross morphologic alterations if > 10-20% of their watershed is covered by impervious surfaces (total imperviousness, TI; Bledsoe and Watson, 2001; Chin, 2006; Table 1). Many of these studies may, however, underestimate the influence of urbanization by using insensitive channel metrics and assessing streams in early stages of urbanization. Most importantly, TI, as a measure of urban density, may not adequately represent the way in which urbanization alters the master variables of flow and sediment within a watershed.Hydrologists have long recognized that, rather than the proportion of impervious cover within a watershed, it is the proportion that is directly connected to the stream through stormwater drainage systems that may be a better predictor of urban-induced hydrologic change (Leopold, 1968). Referred to as effective imperviousness (EI) the proportion of impervious cover directly connected to the stream through stormwater drainage systems may also be a better predictor of geomorphic response than is TI. Over the last decade a direct measure of EI has been found to be a better predictor of ecological response in urban streams (Walsh et al., 2012), but use of such a metric has not found its way into geomorphic studies even though TI has been found to be ineffective (e.g., Bledsoe et al.,

Vietz, Geoff J.; Sammonds, Michael J.; Walsh, Christopher J.; Fletcher, Tim D.; Rutherfurd, Ian D.; Stewardson, Michael J.

2014-02-01

44

Soils  

Science.gov (United States)

The purpose of the handout is to identify the three major types of soils: pedalfer, pedocal, and laterite, and to understand the soil profile. This is accomplished with brief descriptions of the soil horizons and the designation of common elements to pedalfers, pedocals, and laterite soils. The handout is concluded with a discussion of soil erosion. Links are provided to the online Physical Geology resources at Georgia Perimeter College.

Pamela Gore

1995-08-29

45

Spectral data treatments for impervious endmember derivation and fraction mapping from Landsat ETM+ imagery: a comparative analysis  

Science.gov (United States)

Various spectral data preprocessing approaches have been used to improve endmember extraction for urban landscape decomposition, yet little is known of their comparative adequacy for impervious surface mapping. This study tested four commonly used spectral data treatment strategies for endmember derivation, including original spectra, image fusion via principal component analysis, spectral normalization, and the minimum noise fraction (MNF) transformation. Land cover endmembers derived using each strategy were used to build a linear spectral mixture analysis (LSMA) model in order to unmix treated image pixels into fraction maps, and an urban imperviousness map was generated by combining the fraction maps representing imperviousness endmembers. A cross-map comparative analysis was then performed to rank the four data treatment types based on such common evaluation indices as the coefficient of determination (R 2) and root mean square error (RMSE). A Landsat 7 ETM+ multispectral image covering the metropolitan region of Shanghai, China was used as the primary dataset, and the model results were evaluated using high-resolution colorinfrared aerial photographs of roughly the same time period. The test results indicated that, with the highest R 2 (0.812) and the lowest RMSE (0.097) among all four preprocessing treatments, the endmembers in the form of MNF-transformed spectra produced the best model output for characterizing urban impervious surfaces. The outcome of this study may provide useful guidance for future impervious surface mapping using medium-resolution remote sensing data.

Wang, Wei; Yao, Xinfeng; Ji, Minhe; Zhang, Jiao

2014-07-01

46

Synergistic use of optical and InSAR data for urban impervious surface mapping: A case study in Hong Kong  

Science.gov (United States)

A wide range of urban ecosystem studies, including urban hydrology, urban climate, land use planning and watershed resource management, require accurate and up-to-date geospatial data of urban impervious surfaces. In this study, the potential of the synergistic use of optical and InSAR data in urban impervious surface mapping at the sub-pixel level was investigated. A case study in Hong Kong was conducted for this purpose by applying a classification and regression tree (CART) algorithm to SPOT 5 multispectral imagery and ERS-2 SAR data. Validated by reference data derived from high-resolution colour-infrared (CIR) aerial photographs, our results show that the addition of InSAR feature information can improve the estimation of impervious surface percentage (ISP) in comparison with using SPOT imagery alone. The improvement is especially notable in separating urban impervious surface from the vacant land/bare ground, which has been a difficult task in ISP modelling with optical remote sensing data. In addition, the results demonstrate the potential to map urban impervious surface by using InSAR data alone. This allows frequent monitoring of world's cities located in cloud-prone and rainy areas. ?? 2009 Taylor & Francis.

Jiang, L.; Liao, M.; Lin, H.; Yang, L.

2009-01-01

47

Soils  

SCPinfonet

...Directive:Identification of areas at risk of soil erosion, organic matter decline, compaction, salinisation and landslides and for Member States to establish programmes of measuresMeasures to address soil contamination...

48

High-quality observation of surface imperviousness for urban runoff modelling using UAV imagery  

Science.gov (United States)

Modelling rainfall-runoff in urban areas is increasingly applied to support flood risk assessment particularly against the background of a changing climate and an increasing urbanization. These models typically rely on high-quality data for rainfall and surface characteristics of the area. While recent research in urban drainage has been focusing on providing spatially detailed rainfall data, the technological advances in remote sensing that ease the acquisition of detailed land-use information are less prominently discussed within the community. The relevance of such methods increase as in many parts of the globe, accurate land-use information is generally lacking, because detailed image data is unavailable. Modern unmanned air vehicles (UAVs) allow acquiring high-resolution images on a local level at comparably lower cost, performing on-demand repetitive measurements, and obtaining a degree of detail tailored for the purpose of the study. In this study, we investigate for the first time the possibility to derive high-resolution imperviousness maps for urban areas from UAV imagery and to use this information as input for urban drainage models. To do so, an automatic processing pipeline with a modern classification method is tested and applied in a state-of-the-art urban drainage modelling exercise. In a real-life case study in the area of Lucerne, Switzerland, we compare imperviousness maps generated from a consumer micro-UAV and standard large-format aerial images acquired by the Swiss national mapping agency (swisstopo). After assessing their correctness, we perform an end-to-end comparison, in which they are used as an input for an urban drainage model. Then, we evaluate the influence which different image data sources and their processing methods have on hydrological and hydraulic model performance. We analyze the surface runoff of the 307 individual subcatchments regarding relevant attributes, such as peak runoff and volume. Finally, we evaluate the model's channel flow prediction performance through a cross-comparison with reference flow measured at the catchment outlet. We show that imperviousness maps generated using UAV imagery processed with modern classification methods achieve accuracy comparable with standard, off-the-shelf aerial imagery. In the examined case study, we find that the different imperviousness maps only have a limited influence on modelled surface runoff and pipe flows. We conclude that UAV imagery represents a valuable alternative data source for urban drainage model applications due to the possibility to flexibly acquire up-to-date aerial images at a superior quality and a competitive price. Our analyses furthermore suggest that spatially more detailed urban drainage models can even better benefit from the full detail of UAV imagery.

Tokarczyk, P.; Leitao, J. P.; Rieckermann, J.; Schindler, K.; Blumensaat, F.

2015-01-01

49

High-quality observation of surface imperviousness for urban runoff modelling using UAV imagery  

Directory of Open Access Journals (Sweden)

Full Text Available Modelling rainfallrunoff in urban areas is increasingly applied to support flood risk assessment particularly against the background of a changing climate and an increasing urbanization. These models typically rely on high-quality data for rainfall and surface characteristics of the area. While recent research in urban drainage has been focusing on providing spatially detailed rainfall data, the technological advances in remote sensing that ease the acquisition of detailed land-use information are less prominently discussed within the community. The relevance of such methods increase as in many parts of the globe, accurate land-use information is generally lacking, because detailed image data is unavailable. Modern unmanned air vehicles (UAVs allow acquiring high-resolution images on a local level at comparably lower cost, performing on-demand repetitive measurements, and obtaining a degree of detail tailored for the purpose of the study. In this study, we investigate for the first time the possibility to derive high-resolution imperviousness maps for urban areas from UAV imagery and to use this information as input for urban drainage models. To do so, an automatic processing pipeline with a modern classification method is tested and applied in a state-of-the-art urban drainage modelling exercise. In a real-life case study in the area of Lucerne, Switzerland, we compare imperviousness maps generated from a consumer micro-UAV and standard large-format aerial images acquired by the Swiss national mapping agency (swisstopo. After assessing their correctness, we perform an end-to-end comparison, in which they are used as an input for an urban drainage model. Then, we evaluate the influence which different image data sources and their processing methods have on hydrological and hydraulic model performance. We analyze the surface runoff of the 307 individual subcatchments regarding relevant attributes, such as peak runoff and volume. Finally, we evaluate the model's channel flow prediction performance through a cross-comparison with reference flow measured at the catchment outlet. We show that imperviousness maps generated using UAV imagery processed with modern classification methods achieve accuracy comparable with standard, off-the-shelf aerial imagery. In the examined case study, we find that the different imperviousness maps only have a limited influence on modelled surface runoff and pipe flows. We conclude that UAV imagery represents a valuable alternative data source for urban drainage model applications due to the possibility to flexibly acquire up-to-date aerial images at a superior quality and a competitive price. Our analyses furthermore suggest that spatially more detailed urban drainage models can even better benefit from the full detail of UAV imagery.

P. Tokarczyk

2015-01-01

50

Soil structural behaviour of flooded soils  

International Nuclear Information System (INIS)

The objectives of this presentation are to: identify factors determining of the structural behaviour of flooded soils, as compared to those acting in upland soils; analyse the influence of reductive processes on aggregate stabilising agents; discuss mechanisms of structural deterioration and recovery during the flooding-drying cycle, on the basis of a case study: cattle trampling effects in the flooding Pampa of Argentina. Flooded soils, now known as Hydric soils, are characteristic of wetlands and irrigated fields cropped to rice (paddy soils). In them, water covers the soil, or is present either at or near the surface of the soil all year or for varying periods of time during the year. Hydric soils belong to different taxa of the FAO-UNESCO Soil Map (2000). Fluvisols, Planosols and Gleysols are widespread distributed in the globe. The generation of redoximorphic features is due to different causes in each of them. Fluvisols are covered part of the year by surface water from river overflows; Planosols are soils having an impervious Bt horizon, supporting perched water during short periods; and Gleysols are soils affected by stagnant water tables during long periods

51

Soils  

International Nuclear Information System (INIS)

For Austria there exists a comprehensive soil data collection, integrated in a GIS (geographical information system). The content values of pollutants (cadmium, mercury, lead, copper, mercury, radio-cesium) are given in geographical charts and in tables by regions and by type of soil (forests, agriculture, greenland, others) for the whole area of Austria. Erosion effects are studied for the Austrian region. Legal regulations and measures for an effective soil protection, reduction of soil degradation and sustainable development in Austria and the European Union are discussed. (a.n.)

52

Downscaling of thermal images over urban areas using the land surface temperature-impervious percentage relationship  

Science.gov (United States)

Intensive expansion and densification of urban areas decreases environmental quality and quality of urban life as exemplified by the urban heat island effect. For this reason, thermal information is becoming an increasingly important data source for integration in urban studies. It is expected that future spaceborne thermal sensors will provide data at appropriate spatial and temporal resolutions for urban studies. Until they become operational, research has to rely on downscaling algorithms increasing the spatial resolution of relatively coarse resolution thermal images albeit having a high temporal resolution. Existing downscaling algorithms, however, have been developed for sharpening images over rural and natural areas, resulting in large errors when applied to urban areas. The objective of this study is to adapt the DisTrad method for downscaling land surface temperature (LST) over urban areas using the relationship between LST and impervious percentage. The proposed approach is evaluated by sharpening aggregated LST derived from Landsat 7 ETM+ imagery collected over the city of Dublin on May 24th 2001. The new approach shows improved downscaling results over urban areas for all evaluated resolutions, especially in an environment with mixed land cover. The adapted DisTrad approach was most successful at a resolution of 480 m, resulting in a correlation of R2 = 0.84 with an observed image at the same resolution. Furthermore, sharpening using the adapted DisTrad approach was able to preserve the spatial autocorrelation present in urban environments. The unmixing performance of the adapted DisTrad approach improves with decreasing resolution due to the fact that the functional relationship between LST and impervious percentage was defined at coarse resolutions.

Essa, W.; van der Kwast, J.; Verbeiren, B.; Batelaan, O.

2013-08-01

53

Road Detection from Remote Sensing Images using Impervious Surface Characteristics: Review and Implication  

Science.gov (United States)

The extraction of road network is an emerging area in information extraction from high-resolution satellite images (HRSI). It is also an interesting field that incorporates various tactics to achieve road network. The process of road detection from remote sensing images is quite complex, due to the presence of various noises. These noises could be the vehicles, crossing lines and toll bridges. Few small and large false road segments interrupt the extraction of road segments that happens due to the similar spectral behavior in heterogeneous objects. To achieve a better level of accuracy, numerous factors play their important role, such as spectral data of satellite sensor and the information related to land surface area. Therefore the interpretation varies on processing of images with different heuristic parameters. These parameters have tuned according to the road characteristics of the terrain in satellite images. There are several approaches proposed and implemented to extract the roads from HRSI comprising a single or hybrid method. This kind of hybrid approach has also improved the accuracy of road extraction in comparison to a single approach. Some characteristics related to impervious and non-impervious surfaces are used as salient features that help to improve the extraction of road area only in the correct manner. These characteristics also used to utilize the spatial, spectral and texture features to increase the accuracy of classified results. Therefore, aforesaid characteristics have been utilized in combination of road spectral properties to extract road network only with improved accuracy. This evaluated road network is quite accurate with the help of these defined methodologies.

Singh, P. P.; Garg, R. D.

2014-11-01

54

Using long time series of Landsat data to monitor impervious surface dynamics: a case study in the Zhoushan Islands  

Science.gov (United States)

Islands are an important part of the marine ecosystem. Increasing impervious surfaces in the Zhoushan Islands due to new development and increased population have an ecological impact on the runoff and water quality. Based on time-series classification and the complement of vegetation fraction in urban regions, Landsat thematic mapper and other high-resolution satellite images were applied to monitor the dynamics of impervious surface area (ISA) in the Zhoushan Islands from 1986 to 2011. Landsat-derived ISA results were validated by the high-resolution Worldview-2 and aerial photographs. The validation shows that mean relative errors of these ISA maps are urbanization processes, the rapid ISA expansions may not be stopped in the near feature.

Zhang, Xiaoping; Pan, Delu; Chen, Jianyu; Zhan, Yuanzeng; Mao, Zhihua

2013-01-01

55

Fabrication of gas impervious edge seal for a bipolar gas distribution assembly for use in a fuel cell  

International Nuclear Information System (INIS)

A process is described for the preparation of a bipolar gas reactant distribution assembly having solid, gas impervious edge seals to prevent leakage of gaseous reactants, which comprises providing a pair of porous plate members provided with peripheral slits, the slits being generally parallel to, and spaced from each of two edges of the plate, filling the slits with a non-porous, fusible gas impervious edge sealing compound, assembling the plate members with the slits therein approximately perpendicular to one another and a layer of fusible sealing material interposed therebetween, hot pressing the assembly at a temperature sufficient to cause a redistribution of the sealant layer into the pores of the adjacent plate surfaces and the edge sealing compound to flow and impregnate the region of the plates adjacent the slits and comingle with the redistributed sealant material to form a continuous layer of sealant along the edges of the assembly

56

Sub-Pixel Mapping of Tree Canopy, Impervious Surfaces, and Cropland in the Laurentian Great Lakes Basin Using MODIS Time-Series Data  

Science.gov (United States)

This research examined sub-pixel land-cover classification performance for tree canopy, impervious surface, and cropland in the Laurentian Great Lakes Basin (GLB) using both timeseries MODIS (MOderate Resolution Imaging Spectroradiometer) NDVI (Normalized Difference Vegetation In...

57

A note on MHD flow of an incomprassible conducting fluid through a porous tube with impervious boundary  

International Nuclear Information System (INIS)

Some features of the flow of a viscous incompressible fluid through a porous tube with impervious boundary with a magnetic field transverse to the flow, have been studied in this paper. It is shown that this MHD flow is self-superposable and an irrotational flow on which it is superposable is determined. Some observations have been made about the vorticity and stream function of the flow by using the property of super-posability and self superposability. (author). 10 refs., 2 tabs

58

Relative importance of impervious area, drainage density, width function, and subsurface storm drainage on flood runoff from an urbanized catchment  

Science.gov (United States)

The literature contains contradictory conclusions regarding the relative effects of urbanization on peak flood flows due to increases in impervious area, drainage density and width function, and the addition of subsurface storm drains. We used data from an urbanized catchment, the 14.3 km2 Dead Run watershed near Baltimore, Maryland, USA, and the physics-based gridded surface/subsurface hydrologic analysis (GSSHA) model to examine the relative effect of each of these factors on flood peaks, runoff volumes, and runoff production efficiencies. GSSHA was used because the model explicitly includes the spatial variability of land-surface and hydrodynamic parameters, including subsurface storm drains. Results indicate that increases in drainage density, particularly increases in density from low values, produce significant increases in the flood peaks. For a fixed land-use and rainfall input, the flood magnitude approaches an upper limit regardless of the increase in the channel drainage density. Changes in imperviousness can have a significant effect on flood peaks for both moderately extreme and extreme storms. For an extreme rainfall event with a recurrence interval in excess of 100 years, imperviousness is relatively unimportant in terms of runoff efficiency and volume, but can affect the peak flow depending on rainfall rate. Changes to the width function affect flood peaks much more than runoff efficiency, primarily in the case of lower density drainage networks with less impermeable area. Storm drains increase flood peaks, but are overwhelmed during extreme rainfall events when they have a negligible effect. Runoff in urbanized watersheds with considerable impervious area shows a marked sensitivity to rainfall rate. This sensitivity explains some of the contradictory findings in the literature.

Ogden, Fred L.; Raj Pradhan, Nawa; Downer, Charles W.; Zahner, Jon A.

2011-12-01

59

Understanding the effects of the impervious surfaces pattern on land surface temperature in an urban area  

Science.gov (United States)

It is well known that urban impervious surface (IS) has a warming effect on urban land surface temperature (LST). However, the influence of an IS's structure, components, and spatial distribution on LST has rarely been quantitatively studied within strictly urban areas. Using ETM+ remote sensing images from the downtown area of Shanghai, China in 2010, this study characterized and quantified the influence of the IS spatial pattern on LST by selecting the percent cover of each IS cover feature and ten configuration metrics. The IS fraction was estimated by linear spectral mixture analysis (LSMA), and LST was retrieved using a mono-window algorithm. The results indicate that high fraction IS cover features account for the majority of the study area. The high fraction IS cover features are widely distributed and concentrated in groups, which is similar with that of high temperature zones. Both the percent composition and the configuration of IS cover features greatly affect the magnitude of LST, but the percent composition is a more important factor in determining LST than the configuration of those features. The significances and effects of the given configuration variables on LST vary greatly among IS cover features.

Nie, Qin; Xu, Jianhua

2014-09-01

60

Automated mapping of sub-pixel impervious surface area from landsat imagery  

Science.gov (United States)

The past few decades have seen rapid, global urbanization. Remotely sensed imagery is the best source of information about the extent of urbanization, but extracting urban extent from remotely sensed imagery is often an intensive, supervised task for analysts to perform. This project presents a fully automated method to extract impervious surface area (ISA), an important component of urban expansion, from Landsat TM and similar sensors. These moderate resolution sensors have a multi-decade collection archive, sub-monthly revisit rate and have served as a model for other national and commercial programs. The unsupervised methodology proposed herein, termed the PEEL process (pre-processing, endmember extraction and labeling), is an SMA (spectral mixture analysis) technique that uses as inputs endmembers that have been labeled by a SVM (support vector machine) classification through the fusion of the PanTex GLCM-based texture measure and endmembers drawn from the SMACC (sequential maximum angle convex cone) algorithm. Labels are provided to endmembers with an overall accuracy of 94% across 13 Landsat scenes from different sensor types and of several regions and urban forms. Multiple unmixing methods are tested, with BNMESMA (brightness normalized multiple endmember spectral mixture analysis) performing the best with a RMSE of 0.276. Caution is given regarding the value of RMSE as a metric for comparing method accuracy and more detailed error metrics are introduced. The method is shown as a viable template for mapping ISA across multiple scenes and as a useful framework for analyzing large archives of imagery with a common, automatable methodology.

Kamphaus, Benjamin D.

61

Application of MODIS Normalized Differential Vegetation Index for Local Land Use Indicators of Impervious Surface Areas  

Science.gov (United States)

Data derived from satellite measurements offer tremendous potential to contribute to environmental indicators broadly, and land cover/use indicators specifically, given satellite data's consistent, repetitive nature with broad spatial and temporal coverage. This study focuses on the translation of satellite data into meaningful measures that fit within the frame of environmental indicators used by policymakers, resources managers, and the general public. The study area encompasses the Greater Cincinnati Area (6,898 km2), a mid-sized city seeking to address sustainability in the context of urban change and growth. At the center of the study area is downtown Cincinnati in Hamilton County, with suburban areas extending into parts of the seven surrounding counties. Hamilton County staff are particularly interested in tracking impervious surface areas (ISAs) and forest cover as both have been shown to impact nearby water quality. The purpose of this study is to provide Hamilton County and other planning organizations with near real-time information on ISAs and forest cover through a simple, inexpensive methodology that leverages publicly available satellite data products. We obtained 250m resolution Normalized Differential Vegetation Indices (NDVI) data files derived from NASA MODIS (MOD13Q1) for 16-day periods in June/July of 2001-2006. NDVI is calculated based on transformations of the red (620-670 nm), near- infrared (841-876 nm), and blue (459-479 nm) bands designed to enhance the vegetation signal and allow for comparison in terrestrial photosynthetic activity. We examined multiple thresholds of NDVI to act as a surrogate for ISAs (low NDVI) and forest cover (high NDVI). We also calculated changes in NDVI throughout the study period and correlated large decreases in NDVI to known large developments. While this method has potential, further study is needed to ground truth the results, a process that is currently underway. In addition, calculation of NDVI with higher-resolution LANDSAT or ASTER data may improve the results.

Zell, E.; Weber, S.; Zewatsky, J.; Engel-Cox, J.

2007-12-01

62

EFFECT OF BROKEN IMPERVIOUS IRON LAYER ON WATER AVAILABILITY TO SEMI-ARID NORTHERN GHANAIAN FERRIC LIXISOLS  

OpenAIRE

Rainwater is not readily available to sandy loam Ghanaian ferric lixisols. In an attempt to increase water availability to Nyankpala ferric lixisols, their impervious iron pan was broken. Average yield (number of bags) of maize from ferric lexisol with ironpan broken was compared with that with iron pan unbroken. At an average annual rainfall of 64.125 to 106.775 mm for Nyampkala, ferric lexisol with or without iron pan broken yielded similar quantity (20-25bgs/ha) of maize. Breaking of ironp...

Akwasi Asamoah; Charles Antwi-Boasiako; Kwasi Frimpong-Mensah

2013-01-01

63

Performance of heterogeneous earthfill dams under earthquakes: optimal location of the impervious core  

OpenAIRE

Earthfill dams are man-made geostructures which may be especially damaged by seismic loadings, because the soil skeleton they are made of suffers remarkable modifications in its mechanical properties, as well as changes of pore water pressure and flow of this water inside their pores, when subjected to vibrations. The most extreme situation is the dam failure due to soil liquefaction. Coupled finite element numerical codes are a useful tool to assess the safety of these dams. In this paper th...

Lo?pez-querol, S.; Moreta, P. J. M.

2008-01-01

64

Quantification of Impervious Surfaces Along the Wasatch Front, Utah: AN Object-Based Image Analysis Approach to Identifying AN Indicator for Wetland Stress  

Science.gov (United States)

The Remote Sensing/GIS Laboratory at Utah State University, in cooperation with the United States Environmental Protection Agency, is quantifying impervious surfaces for three watershed sub-basins in Utah. The primary objective of developing watershed-scale quantifications of impervious surfaces is to provide an indicator of potential impacts to wetlands that occur within the Wasatch Front and along the Great Salt Lake. A geospatial layer of impervious surfaces can assist state agencies involved with Utah's Wetlands Program Plan (WPP) in understanding the impacts of impervious surfaces on wetlands, as well as support them in carrying out goals and actions identified in the WPP. The three watershed sub-basins, Lower Bear-Malad, Lower Weber, and Jordan, span the highly urbanized Wasatch Front and are consistent with focal areas in need of wetland monitoring and assessment as identified in Utah's WPP. Geospatial layers of impervious surface currently exist in the form of national and regional land cover datasets; however, these datasets are too coarse to be utilized in fine-scale analyses. In addition, the pixel-based image processing techniques used to develop these coarse datasets have proven insufficient in smaller scale or detailed studies, particularly when applied to high-resolution satellite imagery or aerial photography. Therefore, object-based image analysis techniques are being implemented to develop the geospatial layer of impervious surfaces. Object-based image analysis techniques employ a combination of both geospatial and image processing methods to extract meaningful information from high-resolution imagery. Spectral, spatial, textural, and contextual information is used to group pixels into image objects and then subsequently used to develop rule sets for image classification. eCognition, an object-based image analysis software program, is being utilized in conjunction with one-meter resolution National Agriculture Imagery Program (NAIP) aerial photography from 2011.

Leydsman-McGinty, E. I.; Ramsey, R. D.; McGinty, C.

2013-12-01

65

HISTORICAL ANALYSIS OF THE RELATIONSHIP OF STREAMFLOW FLASHINESS WITH POPULATION DENSITY, IMPERVIOUSNESS, AND PERCENT URBAN LAND COVER IN THE MID-ATLANTIC REGION (1)  

Science.gov (United States)

Historical US Census population data was used to estimate population density for 1930-2000 and satellite imagery from circa 1973, 1992, and 2001 was used to estimate the degree of urban development and the percent imperviousness (for 1992 and 2001) for a set of 150 small (< 13...

66

HISTORICAL ANALYSIS OF THE RELATIONSHIP OF STREAMFLOW FLASHINESS WITH POPULATION DENSITY, IMPERVIOUSNESS, AND PERCENT URBAN LAND COVER IN THE MID-ATLANTIC REGION  

Science.gov (United States)

Methods: This study is an examination of the relationship between stream flashiness and watershed-scale estimates of percent imperviousness, degree of urban development, and population density for 150 watersheds with long-term USGS National Water Information System (NWIS) histori...

67

Mapping Impervious Surface Expansion using Medium-resolution Satellite Image Time Series: A Case Study in the Yangtze River Delta, China  

Science.gov (United States)

Cities have been expanding rapidly worldwide, especially over the past few decades. Mapping the dynamic expansion of impervious surface in both space and time is essential for an improved understanding of the urbanization process, land-cover and land-use change, and their impacts on the environment. Landsat and other medium-resolution satellites provide the necessary spatial details and temporal frequency for mapping impervious surface expansion over the past four decades. Since the US Geological Survey opened the historical record of the Landsat image archive for free access in 2008, the decades-old bottleneck of data limitation has gone. Remote-sensing scientists are now rich with data, and the challenge is how to make best use of this precious resource. In this article, we develop an efficient algorithm to map the continuous expansion of impervious surface using a time series of four decades of medium-resolution satellite images. The algorithm is based on a supervised classification of the time-series image stack using a decision tree. Each imerpervious class represents urbanization starting in a different image. The algorithm also allows us to remove inconsistent training samples because impervious expansion is not reversible during the study period. The objective is to extract a time series of complete and consistent impervious surface maps from a corresponding times series of images collected from multiple sensors, and with a minimal amount of image preprocessing effort. The approach was tested in the lower Yangtze River Delta region, one of the fastest urban growth areas in China. Results from nearly four decades of medium-resolution satellite data from the Landsat Multispectral Scanner (MSS), Thematic Mapper (TM), Enhanced Thematic Mapper plus (ETM+) and China-Brazil Earth Resources Satellite (CBERS) show a consistent urbanization process that is consistent with economic development plans and policies. The time-series impervious spatial extent maps derived from this study agree well with an existing urban extent polygon data set that was previously developed independently. The overall mapping accuracy was estimated at about 92.5% with 3% commission error and 12% omission error for the impervious type from all images regardless of image quality and initial spatial resolution.

Gao, Feng; DeColstoun, Eric Brown; Ma, Ronghua; Weng, Qihao; Masek, Jeffrey G.; Chen, Jin; Pan, Yaozhong; Song, Conghe

2012-01-01

68

Using environmental metrics to describe the spatial and temporal evolution of landscape structure and soil hydrology and fertility  

OpenAIRE

In this work a methodology using Geographical Information Systems was developed and applied to a temporal series of land cover layers (for the years 1956, 1978, 1991 and 2010) in the municipality of Vall dUx, Eastern Spain. Four types of metrics were implemented (1) spatial representation of the degree of artificialisation, (2) patchiness and fragmentation, (3) fertility dynamics of soils according to their land capability, and (4) soils imperviousness and loss of water retention capacit...

Pascual Aguilar, Juan Antonio; Sanz Garci?a, Juana; Bustamante Gutie?rrez, Irene; Kallache, Malaak

2011-01-01

69

Influence of cracking in the desiccation process of clay soils  

OpenAIRE

It is well known that clayey soils undergoing desiccation tend to shrink and eventually crack. Analysis of the behaviour and influence of cracks in these types of soils is very important in several engineering fields such as mine tailing dams, long-term radioactive waste storage, impervious core of earth dams, and in any situation where clay is used as a barrier to fluid flow. Loss of humidity and cracking changes the permeability of such barriers that may no longer work properly and pose pot...

Levatti, Hector Ulises; Prat Catala?n, Pere; Ledesma Villalba, Alberto

2009-01-01

70

Attributes for MRB_E2RF1 Catchments by Major River Basins in the Conterminous United States: NLCD 2001 Imperviousness  

Science.gov (United States)

This tabular data set represents the mean percent impervious surface from the Imperviousness Layer of the National Land Cover Dataset 2001, (LaMotte and Wieczorek, 2010), compiled for every MRB_E2RF1 catchment of selected Major River Basins (MRBs, Crawford and others, 2006). The source data set represents imperviousness for the conterminous United States for 2001. The Imperviousness Layer of the National Land Cover Data Set for 2001 was produced through a cooperative project conducted by the Multi-Resolution Land Characteristics (MRLC) Consortium. The MRLC Consortium is a partnership of Federal agencies (http://www.mrlc.gov), consisting of the U.S. Geological Survey (USGS), the National Oceanic and Atmospheric Administration (NOAA), the U.S. Environmental Protection Agency (USEPA), the U.S. Department of Agriculture (USDA), the U.S. Forest Service (USFS), the National Park Service (NPS), the U.S. Fish and Wildlife Service (USFWS), the Bureau of Land Management (BLM), and the USDA Natural Resources Conservation Service (NRCS). The MRB_E2RF1 catchments are based on a modified version of the U.S. Environmental Protection Agency's (USEPA) ERF1_2 and include enhancements to support national and regional-scale surface-water quality modeling (Nolan and others, 2002;Brakebill and others, 2011). Data were compiled for every MRB_E2RF1 catchment for the conterminous United States covering New England and Mid-Atlantic (MRB1), South Atlantic-Gulf and Tennessee (MRB2), the Great Lakes, Ohio, Upper Mississippi, and Souris-Red-Rainy (MRB3), the Missouri (MRB4), the Lower Mississippi, Arkansas-White-Red, and Texas-Gulf (MRB5), the Rio Grande, Colorado, and the Great basin (MRB6), the Pacific Northwest (MRB7) river basins, and California (MRB8).

Wieczorek, Michael E.; LaMotte, Andrew E.

2010-01-01

71

Extraction and Analysis of Impervious Surfaces Based on a Spectral Un-Mixing Method Using Pearl River Delta of China Landsat TM/ETM+ Imagery from 1998 to 2008  

OpenAIRE

Impervious surface area (ISA) is considered as an indicator of environment change and is regarded as an important input parameter for hydrological cycle simulation, water management and area pollution assessment. The Pearl River Delta (PRD), the 3rd most important economic district of China, is chosen in this paper to extract the ISA information based on Landsat images of 1998, 2003 and 2008 by using a linear spectral un-mixing method and to monitor impervious surface change by analyzing the ...

Renrong Chen; Fenglei Fan; Yingbin Deng

2012-01-01

72

Fabrication of gas impervious edge seal for a bipolar gas distribution assembly for use in a fuel cell  

Science.gov (United States)

A bipolar gas reactant distribution assembly for use in a fuel cell is disclosed, the assembly having a solid edge seal to prevent leakage of gaseous reactants wherein a pair of porous plates are provided with peripheral slits generally parallel to, and spaced apart from two edges of the plate, the slit being filled with a solid, fusible, gas impervious edge sealing compound. The plates are assembled with opposite faces adjacent one another with a layer of a fusible sealant material therebetween the slits in the individual plates being approximately perpendicular to one another. The plates are bonded to each other by the simultaneous application of heat and pressure to cause a redistribution of the sealant into the pores of the adjacent plate surfaces and to cause the edge sealing compound to flow and impregnate the region of the plates adjacent the slits and comingle with the sealant layer material to form a continuous layer of sealant along the edges of the assembled plates.

Kaufman, Arthur (West Orange, NJ); Werth, John (Princeton, NJ)

1986-01-01

73

The use of single-date MODIS imagery for estimating large-scale urban impervious surface fraction with spectral mixture analysis and machine learning techniques  

Science.gov (United States)

Urban impervious surface information is essential for urban and environmental applications at the regional/national scales. As a popular image processing technique, spectral mixture analysis (SMA) has rarely been applied to coarse-resolution imagery due to the difficulty of deriving endmember spectra using traditional endmember selection methods, particularly within heterogeneous urban environments. To address this problem, we derived endmember signatures through a least squares solution (LSS) technique with known abundances of sample pixels, and integrated these endmember signatures into SMA for mapping large-scale impervious surface fraction. In addition, with the same sample set, we carried out objective comparative analyses among SMA (i.e. fully constrained and unconstrained SMA) and machine learning (i.e. Cubist regression tree and Random Forests) techniques. Analysis of results suggests three major conclusions. First, with the extrapolated endmember spectra from stratified random training samples, the SMA approaches performed relatively well, as indicated by small MAE values. Second, Random Forests yields more reliable results than Cubist regression tree, and its accuracy is improved with increased sample sizes. Finally, comparative analyses suggest a tentative guide for selecting an optimal approach for large-scale fractional imperviousness estimation: unconstrained SMA might be a favorable option with a small number of samples, while Random Forests might be preferred if a large number of samples are available.

Deng, Chengbin; Wu, Changshan

2013-12-01

74

The Integrated Use of DMSP-OLS Nighttime Light and MODIS Data for Monitoring Large-Scale Impervious Surface Dynamics: A Case Study in the Yangtze River Delta  

Directory of Open Access Journals (Sweden)

Full Text Available The timely and reliable estimation of imperviousness is essential for the scientific understanding of human-Earth interactions. Due to the unique capacity of capturing artificial light luminosity and long-term data records, the Defense Meteorological Satellite Program (DMSPs Operational Line-scan System (OLS nighttime light (NTL imagery offers an appealing opportunity for continuously characterizing impervious surface area (ISA at regional and continental scales. Although different levels of success have been achieved, critical challenges still remain in the literature. ISA results generated by DMSP-OLS NTL alone suffer from limitations due to systemic defects of the sensor. Moreover, the majority of developed methodologies seldom consider spatial heterogeneity, which is a key issue in coarse imagery applications. In this study, we proposed a novel method for multi-temporal ISA estimation. This method is based on a linear regression model developed between the sub-pixel ISA fraction and a multi-source index with the integrated use of DMSP-OLS NTL and MODIS NDVI. In contrast with traditional regression analysis, we incorporated spatial information to the regression model for obtaining spatially adaptive coefficients at the per-pixel level. To produce multi-temporal ISA maps using a mono-temporal reference dataset, temporally stable samples were extracted for model training and validation. We tested the proposed method in the Yangtze River Delta and generated annual ISA fraction maps for the decade 20002009. According to our assessments, the proposed method exhibited substantial improvements compared with the standard linear regression model and provided a feasible way to monitor large-scale impervious surface dynamics.

Zhenfeng Shao

2014-09-01

75

Land-Cover and Imperviousness Data for Regional Areas near Denver, Colorado; Dallas-Fort Worth, Texas; and Milwaukee-Green Bay, Wisconsin - 2001  

Science.gov (United States)

This report describes the processing and results of land-cover and impervious surface derivation for parts of three metropolitan areas being studied as part of the U.S. Geological Survey's (USGS) National Water-Quality Assessment (NAWQA) Program Effects of Urbanization on Stream Ecosystems (EUSE). The data were derived primarily from Landsat-7 Enhanced Thematic Mapper Plus (ETM+) satellite imagery from the period 1999-2002, and are provided as 30-meter resolution raster datasets. Data were produced to a standard consistent with data being produced as part of the USGS National Land Cover Database 2001 (NLCD01) Program, and were derived in cooperation with, and assistance from, NLCD01 personnel. The data were intended as surrogates for NLCD01 data because of the EUSE Program's time-critical need for updated land-cover for parts of the United States that would not be available in time from the NLCD01 Program. Six datasets are described in this report: separate land-cover (15-class categorical data) and imperviousness (0-100 percent continuous data) raster datasets for parts of the general Denver, Colorado area (South Platte River Basin), Dallas-Fort Worth, Texas area (Trinity River Basin), and Milwaukee-Green Bay, Wisconsin area (Western Lake Michigan Drainages).

Falcone, James; Pearson, Daniel

2006-01-01

76

Toward a geoinformatics framework for understanding the social and biophysical influences on urban nutrient pollution due to residential impervious service connectivity  

Science.gov (United States)

Water sustainability has been recognized as a fundamental problem of science whose solution relies in part on high-performance computing. Stormwater management is a major concern of urban sustainability. Understanding interactions between urban landcover and stormwater nutrient pollution requires consideration of fine-scale residential stormwater management, which in turn requires high-resolution LIDAR and landcover data not provided through national spatial data infrastructure, as well as field observation at the household scale. The objectives of my research are twofold: (1) advance understanding of the relationship between residential stormwater management practices and the export of nutrient pollution from stormwater in urbanized ecosystems; and (2) improve the informatics workflows used in community ecohydrology modeling as applied to heterogeneous urbanized ecosystems. In support of these objectives, I present preliminary results from initial work to: (1) develop an ecohydrology workflow platform that automates data preparation while maintaining data provenance and model metadata to yield reproducible workflows and support model benchmarking; (2) perform field observation of existing patterns of residential rooftop impervious surface connectivity to stormwater networks; and (3) develop Regional Hydro-Ecological Simulation System (RHESSys) models for watersheds in Baltimore, MD (as part of the Baltimore Ecosystem Study (BES) NSF Long-Term Ecological Research (LTER) site) and Durham, NC (as part of the NSF Urban Long-Term Research Area (ULTRA) program); these models will be used to simulate nitrogen loading resulting from both baseline residential rooftop impervious connectivity and for disconnection scenarios (e.g. roof drainage to lawn v. engineered rain garden, upslope v. riparian). This research builds on work done as part of the NSF EarthCube Layered Architecture Concept Award where a RHESSys workflow is being implemented in an iRODS (integrated Rule-Oriented Data System) environment. Modeling the ecohydrology of urban ecosystems in a reliable and reproducible manner requires a flexible scientific workflow platform that allows rapid prototyping with large-scale spatial datasets and model refinement integrating expert knowledge with local datasets and household surveys.

Miles, B.; Band, L. E.

2012-12-01

77

Exploring the Influence of Impervious Surface Density and Shape on Urban Heat Islands in the Northeast USA Using MODIS and Landsat  

Science.gov (United States)

Impervious surface area (ISA) from the National Land Cover Database (NLCD) 2001 and land surface temperature (LST) from MODIS averaged over three annual cycles (2003-2005) are used in a spatial analysis to assess the urban heat island (UHI) signature and its relationship to settlement size and shape, development intensity distribution, and land cover composition for 42 urban settlements embedded in forest biomes in the Northeastern United States. Development intensity zones, based on percent ISA, are defined for each urban area emanating outward from the urban core to nearby rural areas and are used to stratify land surface temperature. The stratification is further constrained by biome type and elevation to insure objective intercomparisons between urban zones within an urban settlement and between settlements. Stratification based on ISA allows the definition of hierarchically ordered urban zones that are consistent across urban settlements and scales. In addition to the surrounding ecological context, we find that the settlement size and shape as well as the development intensity distribution significantly influence the amplitude of summer daytime UHI. Within the Northeastern US temperate broadleaf mixed forest, UHI magnitude is positively related to the logarithm of the urban area size. Our study indicates that for similar urban area sizes, the development intensity distribution is one of the major drivers of UHI. In addition to urban area size and development intensity distribution, this analysis shows that both the shape of the urban area and the land cover composition in the surrounding rural area play an important role in modulating the UHI magnitude in different urban settlements. Our results indicate that remotely sensed urban area size and shape as well as the development intensity distribution influence UHI amplitude across regional scales.

Zhang, Ping; Imhoff, Marc L.; Bounoua, Lahouri; Wolfe, Robert E.

2011-01-01

78

Soil Composition  

Science.gov (United States)

Soil is essential for life on Earth. It is needed for food, air, clothing and so much more. Discussion topics include the terms 'soil', 'dirt', and 'sediment', factors affecting the formation of soils, soil horizons, and the twelve orders of soils. In a hands-on activity, students will collect soil samples from three different locations, use online resources to determine texture and particle makeup, and record their observations.

Chris Fox

79

Soil Moisture  

Science.gov (United States)

NOAA's Climate Prediction Center offers this useful data site on soil moisture across the US. Soil moisture data are provided here as color contour maps that represent calculated soil moisture, anomalies, and percentiles for the most recent day, monthly, and twelve-month time periods. Also provided here are 25-year average soil moisture & soil wetness summaries. In addition to providing recent and historical data, the Soil Moisture site features soil moisture forecasts for two-week, monthly, and seasonal intervals, based on the National Weather Service Medium Range Forecast (MRF) and the Constructed Analog on Soil Moisture (CAS).

2000-01-01

80

Gully Growth Patterns and Soil Loss under Rainfall at Urban Underground Drainage Construction Site, Uyo  

Directory of Open Access Journals (Sweden)

Full Text Available This study investigated, evaluated and modeled patterns of growth of gully morphometric dimension and soil loss volume under prevailing rainfall on the slopes of land graded for the construction of underground drainage at Uyo but delayed in completion. Land grading at underground (tunnel drainage construction site rendered the exposed surface very impervious but young ephemeral gullies developed due to delays in completion. Data on gully morphometric dimension, soil loss and depth of rainfall were analyzed using SPSS ver. 17 statistical package. Mean gully growth in length, width and depth were different at 2.540.86, 0.9230.29 and 0.410.11 m, respectively, yielding 3.870.08 m2 as mean volume of soil loss at full stage. Cubic polynomial was best-fit model for growth in length (R2 = 79% and width (R2 = 69% using weekly rainfall for an annual season. All gully sites had constant depth change, better predicted by quadratic (R2 = 13% than linear (R2 = 9% functions. Mean volume of soil loss per unit rainfall amount varied with low, medium and high rainfall amount and was highest at slope bottom (33 cm3/cm and least at the crest (6.99 cm3/cm with R2 = 38-34%. Land grading to impervious sublayer produced constant depth change in all gullies at the sites. The models for morphometric incremental growth and soil loss volume under the rainfall effect was significantly improved (p<0.05 by bifurcating the lumped annual curve into two growth periods in a year: the periods for increasing rainfall (from week 10-30 and for receding rainfall (from week 31-43 in a year and applying quadratic regressing functions on each (R2 = 91-99%. Rainfall was the principal gully factor and construction delays should be avoided.

O.E. Essien

2012-08-01

81

Mediterranean soils  

OpenAIRE

Mediterranean soils are soils which form under a Mediterranean climate. They are variously called Terra Rossa (on hard limestone) and Red Mediterranean Soils. Not all soils in a Mediterranean environment are, however, qualified as such because normal pedogenetic development may be hampered by erosion (rejuvenation of the profile), lack of time, lack of water or unfavorable parent material characteristics.

Verheyen, Willy; La Rosa, Diego

2005-01-01

82

Modeling urban heat islands in heterogeneous land surface and its correlation with impervious surface area by using night-time ASTER satellite data in highly urbanizing city, Delhi-India  

Science.gov (United States)

The present study is an assessment and identification of urban heat island (UHI) in the environment of one of the fastest urbanizing city of India, Delhi Metropolis, employing satellite image of ASTER and Landsat 7 ETM+ in the thermal infrared region 3-14 ?m. Temporal (2001 and 2005) ASTER datasets were used to analyze the spatial structure of the thermal urban environment subsequently urban heat island (UHI) in relation to the urban surface characteristics and land use/land cover (LULC). The study involves derivation of parameters governing the surface heat fluxes, constructing statistics of ASTER thermal infrared images along with validation through intensive in situ measurements. The average images reveal spatial and temporal variations of land surface temperature (LST) of night-time and distinct microclimatic patterns. Central Business District (CBD) of Delhi, (Connaught Place, a high density built up area), and commercial/industrial areas display heat islands condition with a temperature greater than 4 C compared to the suburbs. The small increase in surface temperature at city level is mainly attributed to cumulative impact of human activities, changes in LULC pattern and vegetation density. In this study the methodology takes into account spatially-relative surface temperatures and impervious surface fraction value to measure surface UHI intensity between the urban land cover and rural surroundings. Both the spatial and temporal variation in surface temperature associated with impervious surface area (ISA) has been evaluated to assess the effect of urbanization on the local climate.

Mallick, Javed; Rahman, Atiqur; Singh, Chander Kumar

2013-08-01

83

Soil Texture  

Science.gov (United States)

This University of Florida website educates the public about soil texture, which is the distribution of sizes of mineral particles found in soils. After learning the basics about soil separates, students and educators can learn about the USDA textural triangle and the characteristics of the twelve textural classes. Researchers can discover how to determine the correct soil texture in the field. The website addresses the important role soil textures play in the determination of proper land use activities and management practices. Visitors will also find a short discussion about other factors that affect the behavior and qualities of soils.

2008-01-04

84

Solarization soil  

International Nuclear Information System (INIS)

Solar energy could be used in pest control, in soil sterilization technology. The technique consists of covering humid soils by plastic films steadily fixed to the soil. Timing must be in summer during 4-8 weeks, where soil temperature increases to degrees high enough to control pests or to produce biological and chemical changes. The technique could be applied on many pests soil, mainly fungi, bacteria, nematods, weeds and pest insects. The technique could be used in greenhouses as well as in plastic film covers or in orchards where plastic films present double benefits: soil sterilization and production of black mulch. Mechanism of soil solarization is explained. Results show that soil solarization can be used in pest control after fruit crops cultivation and could be a method for an integrated pest control. 9 refs

85

Groundwater Dynamics in Drained Soils of the Bi?-fi eld District  

Directory of Open Access Journals (Sweden)

Full Text Available The main goal of five-year stationary investigations (2001-2006 was to assess groundwater dynamics in the Bi?-field district, as well as the type of soil moistening of agricultural soils spreading over 5838 ha. Detailed hydropedological investigations were carried out in 2000 and a soil map of the region was produced (scale = 1:10000 using universal kriging. Soil investigations identified six pedosystematic units: alluvial-gley, semigley-pseudogley, eugley hypogley, humogley, eugley amphigley and drained soils. Based on permanent monitoring of piezometer groundwater (piezometer depth up to 4.0 m in the period from 2001 to 2006, the following major soil moistening types and subtypes of the separated soil units were determined: semigley-pseudogely, hypogley, humogley, amphigley and drained. Using the correlation method, more intensive groundwater communication was determined in the studied soil profiles with the River Bi? water (r = 0.65-0.69 than with the River Sava water (r = 0.23-0.69, notably in hypogley soils, which cover 54.3% of the studied area. Analysis of the obtained piezometer water level curves indicated a very strong mutual correlation between the groundwater level dynamics in monitored hydrogeological piezometers of 9 m depth (r = 0.87-0.98, as well as a strong correlation (r = 0.75-0.94 between hydrogeological and hydropedological piezometers of 4 m depth. A particularly strong correlation (r = 0.85-0.94 was recorded between hydrogeological and hydropedological piezometers installed in hypogley soil. These data confirm marked vertical communication of groundwater in the deep aquifer with water of the shallow soil aquifer, indicating that the surface layer of the studied area, mainly made up of silty clay loams to silty clays, is not impervious.

Ivan Musta?

2011-03-01

86

Soil Erosion  

OpenAIRE

One element of the CIVCAL project Web-based resources containing images, tables, texts and associated data of the Soil Erosion. The word "erosion" is derived from the Latin "erosio", meaning to "to gnaw away". In general terms soil erosion implies the physical removal of topsoil by various agents, including rain, water flowing over and through the soil profile, wind, ice or gravitational pull. This part of the CIVCAL project introduces the processes and control of soil erosion, includi...

Kumaraswamy, Mohan

2002-01-01

87

Extraction and analysis of impervious surfaces based on a spectral un-mixing method using Pearl River Delta of China Landsat TM/ETM+ imagery from 1998 to 2008.  

Science.gov (United States)

Impervious surface area (ISA) is considered as an indicator of environment change and is regarded as an important input parameter for hydrological cycle simulation, water management and area pollution assessment. The Pearl River Delta (PRD), the 3rd most important economic district of China, is chosen in this paper to extract the ISA information based on Landsat images of 1998, 2003 and 2008 by using a linear spectral un-mixing method and to monitor impervious surface change by analyzing the multi-temporal Landsat-derived fractional impervious surface. Results of this study were as follows: (1) the area of ISA in the PRD increased 79.09% from 1998 to 2003 and 26.88% from 2003 to 2008 separately; (2) the spatial distribution of ISA was described according to the 1998/2003 percentage respectively. Most of middle and high percentage ISA was located in northwestern and southeastern of the whole delta, and middle percentage ISA was mainly located in the city interior, high percentage ISA was mainly located in the suburban around the city accordingly; (3) the expanding direction and trend of high percentage ISA was discussed in order to understand the change of urban in this delta; High percentage ISA moved from inner city to edge of urban area during 1998-2003 and moved to the suburban area that far from the urban area mixed with jumpily and gradually during 2003-2008. According to the discussion of high percentage ISA spatial expanded direction, it could be found out that high percentage ISA moved outward from the centre line of Pearl River of the whole delta while a high ISA percentage in both shores of the Pearl River Estuary moved toward the Pearl River; (4) combining the change of ISA with social conditions, the driving relationship was analyzed in detail. It was evident that ISA percentage change had a deep relationship with the economic development of this region in the past ten years. Contemporaneous major sport events (16th Asia Games of Guangzhou, 26th Summer Universidad of Shenzhen) and the government policies also promoted the development of the ISA. Meanwhile, topographical features like the National Nature Reserve of China restricted and affected the expansion of the ISA. Above all, this paper attempted to extract ISA in a major region of the PRD; the temporal and spatial analyses to PRD ISA demonstrated the drastic changes in developed areas of China. These results were important and valuable for land use management, ecological protection and policy establishment. PMID:22438741

Deng, Yingbin; Fan, Fenglei; Chen, Renrong

2012-01-01

88

Extraction and Analysis of Impervious Surfaces Based on a Spectral Un-Mixing Method Using Pearl River Delta of China Landsat TM/ETM+ Imagery from 1998 to 2008  

Directory of Open Access Journals (Sweden)

Full Text Available Impervious surface area (ISA is considered as an indicator of environment change and is regarded as an important input parameter for hydrological cycle simulation, water management and area pollution assessment. The Pearl River Delta (PRD, the 3rd most important economic district of China, is chosen in this paper to extract the ISA information based on Landsat images of 1998, 2003 and 2008 by using a linear spectral un-mixing method and to monitor impervious surface change by analyzing the multi-temporal Landsat-derived fractional impervious surface. Results of this study were as follows: (1 the area of ISA in the PRD increased 79.09% from 1998 to 2003 and 26.88% from 2003 to 2008 separately; (2 the spatial distribution of ISA was described according to the 1998/2003 percentage respectively. Most of middle and high percentage ISA was located in northwestern and southeastern of the whole delta, and middle percentage ISA was mainly located in the city interior, high percentage ISA was mainly located in the suburban around the city accordingly; (3 the expanding direction and trend of high percentage ISA was discussed in order to understand the change of urban in this delta; High percentage ISA moved from inner city to edge of urban area during 19982003 and moved to the suburban area that far from the urban area mixed with jumpily and gradually during 20032008. According to the discussion of high percentage ISA spatial expanded direction, it could be found out that high percentage ISA moved outward from the centre line of Pearl River of the whole delta while a high ISA percentage in both shores of the Pearl River Estuary moved toward the Pearl River; (4 combining the change of ISA with social conditions, the driving relationship was analyzed in detail. It was evident that ISA percentage change had a deep relationship with the economic development of this region in the past ten years. Contemporaneous major sport events (16th Asia Games of Guangzhou, 26th Summer Universidad of Shenzhen and the government policies also promoted the development of the ISA. Meanwhile, topographical features like the National Nature Reserve of China restricted and affected the expansion of the ISA. Above all, this paper attempted to extract ISA in a major region of the PRD; the temporal and spatial analyses to PRD ISA demonstrated the drastic changes in developed areas of China. These results were important and valuable for land use management, ecological protection and policy establishment.

Renrong Chen

2012-02-01

89

Extraction and Analysis of Impervious Surfaces Based on a Spectral Un-Mixing Method Using Pearl River Delta of China Landsat TM/ETM+ Imagery from 1998 to 2008  

Science.gov (United States)

Impervious surface area (ISA) is considered as an indicator of environment change and is regarded as an important input parameter for hydrological cycle simulation, water management and area pollution assessment. The Pearl River Delta (PRD), the 3rd most important economic district of China, is chosen in this paper to extract the ISA information based on Landsat images of 1998, 2003 and 2008 by using a linear spectral un-mixing method and to monitor impervious surface change by analyzing the multi-temporal Landsat-derived fractional impervious surface. Results of this study were as follows: (1) the area of ISA in the PRD increased 79.09% from 1998 to 2003 and 26.88% from 2003 to 2008 separately; (2) the spatial distribution of ISA was described according to the 1998/2003 percentage respectively. Most of middle and high percentage ISA was located in northwestern and southeastern of the whole delta, and middle percentage ISA was mainly located in the city interior, high percentage ISA was mainly located in the suburban around the city accordingly; (3) the expanding direction and trend of high percentage ISA was discussed in order to understand the change of urban in this delta; High percentage ISA moved from inner city to edge of urban area during 19982003 and moved to the suburban area that far from the urban area mixed with jumpily and gradually during 20032008. According to the discussion of high percentage ISA spatial expanded direction, it could be found out that high percentage ISA moved outward from the centre line of Pearl River of the whole delta while a high ISA percentage in both shores of the Pearl River Estuary moved toward the Pearl River; (4) combining the change of ISA with social conditions, the driving relationship was analyzed in detail. It was evident that ISA percentage change had a deep relationship with the economic development of this region in the past ten years. Contemporaneous major sport events (16th Asia Games of Guangzhou, 26th Summer Universidad of Shenzhen) and the government policies also promoted the development of the ISA. Meanwhile, topographical features like the National Nature Reserve of China restricted and affected the expansion of the ISA. Above all, this paper attempted to extract ISA in a major region of the PRD; the temporal and spatial analyses to PRD ISA demonstrated the drastic changes in developed areas of China. These results were important and valuable for land use management, ecological protection and policy establishment. PMID:22438741

Deng, Yingbin; Fan, Fenglei; Chen, Renrong

2012-01-01

90

Overland flow generation on deep soils in Ethiopia (Lake Tana basin): role of soil texture and plough pan  

Science.gov (United States)

Different applications of rainfall/runoff models in Lake Tana basin (Ethiopia) tend to show that on hill slopes there are vast areas that yield a high runoff response and that behave as if the soil would be nearly impervious (up to 20 % of the hilly catchments). This is well beyond the area occupied by rock outcrops. Duricrusts or hardpans of pedogenetic origin are absent in this environment on basaltic rock with mild tropical climate: no silcretes, calcretes or even ferricretes are known to occur in the basin. Field observations show that runoff response from tilled farmlands can however be unexpectedly high, even when deep theoretically well drained Nitisols occur. In the rainy season, rills and ephemeral gullies are created and these often expose a rock-hard plough pan at some 15 cm depth. Due to repeated tillage at constant depth, the downward pressure of the tip of the ox-drawn ard plough compacts the soil aggregates that are located just below the tilled horizon. In this poster we will discuss the need to not only evaluate the effect of soil texture when interpreting rainfall-runoff relations, but also to investigate the structural and hydrological characteristics of such plough pans.

Nyssen, Jan; Dessie, Mekete; Monsieurs, Elise; Poesen, Jean; Admasu, Teshager; Verhoest, Niko; Adgo, Enyew; Deckers, Jozef

2014-05-01

91

Soil suction  

OpenAIRE

Suction is pore water pressure in unsaturated soils and influences other soil characteristics. Suction measurements for 4 different soils (bentonite, stone flour, gray clay sivica and brown clay flysch) are presented. Measurements were performed on compacted and loose material at different water contents using 4 different methods: WP4 dewpoint potentiometer, filter paper, tenziometer and pressure plate apparatus. Additionally the water adsorption was determined for ...

Mac?ek, Matej

2006-01-01

92

Impacts of soil erosion  

OpenAIRE

3.1 Definition of soil functions, soil quality and quality targets The identification of soil functions, properties and processes which are affected by soil erosion is needed to evaluate the impacts of erosion on the soil system. Definition of soil loss tolerance according to soil types and environmental characteristics. 3.2 Development of criteria and indicators to assess soil sustainable use and soil protection measures What are the impacts of soil erosion on soil...

Dorren, Luuk; La Rosa, Diego; Theocharopoulos, Sid P.

2004-01-01

93

Soils electroremediation  

International Nuclear Information System (INIS)

This paper presents data on decontamination experiments performed with soils contaminated by long-lived radioactive caesium isotopes. The contamination was formed about 30 years ago during an accident in the first nuclear power station in the former Czechoslovakia. Because of the large soil quantities that make excavation and storage of these soils in nuclear waste repositories inconvenient from economical and spatial point of view, various methods for in situ or ex situ remediation were sought and tested. For soil contamination by caesium, the time of contact of caesium with the soil is crucial because the caesium ions diffuse inside the crystalline structures of clay minerals where they are virtually irreversibly bound. For such materials, the efficiency of the classic 'soft' decontamination methods, such as leaching, phytoremediation etc., is rather low. Electrochemical decontamination was proposed as the decontamination technique for ex situ application. The method is based on electrolysis at a relatively high current density in a suitable electrolyte. The soil is kept in suspension close to the anode, and owing to the high acidity together with both the high temperature and ion flux, the soil structures are opened or partially disrupted and caesium ions are released. The ions can be separated from the solution, e.g., by using selective ion exchangers. The experimental electrolytic cell was designed for the treatment of thin soil layers containing about 3 g of thein soil layers containing about 3 g of the soil and about 100 mL of electrolyte. The influence of various system parameters, such as electrolyte composition, current-voltage, temperature, and time, on the decontamination efficiency was examined. In the most efficient configuration, a 99+% decontamination level was achieved. For the next step, a bench-scale apparatus was designed that should allow treatment of batches of up to 0.5 kg of soil in one step. (author)

94

Bioremediation of soils contaminated with polycyclic aromatic hydrocarbons  

International Nuclear Information System (INIS)

The Iron Park Superfund site, North Billerica, Massachusetts, is located within a 553 acre operating industrial complex and railyard located approximately 20 miles northwest of Boston. Fifteen acres of this site are designated as the Wastewater Lagoon Area containing lagoons and materials previously dredged from those lagoons. The U.S. Environmental Protection Agency (EPA) placed the Iron Horse Park facility on its National Priorities List in 1984, and a Remedial Investigation (RI) for the site as a whole began n 1985. In September 1988, responding to the presence of these site contaminants, the EPA issued the first Superfund Record of Decision (ROD) in EPA Region I that specified bioremediation as the remedial technology. Specifically, the EPA stipulated biological land treatment cell with an impervious lower liner. In this form of biotreatment, sludges and contaminated soil are placed in the cell in lifts (i.e. layers approximately one foot thick) and the lifts are frequently aerated by tilling while nutrients are applied at optimal levels to stimulate the degradation of organic contaminants by indigenous microorganisms. In its Administrative Order (September 1989), the EPA stipulated cleanup goals to be achieved, and required that a Predesign Evaluation be initiated to ascertain which soil/sludge piles would require treatment. The design and execution of this remediation-focused site evaluation by ENSR forms the subject of this paperthis paper

95

Clay slurry and engineered soils as containment technologies for remediation of contaminated sites  

International Nuclear Information System (INIS)

Clay Slurry and Engineered Soils are containment technologies for remediation of waste disposal sites where leaching, groundwater plumes and surface runoff of contaminants are serious ecological hazards to adjacent environments. This technology is a patent-pending process which involves the use of conditioned clay materials mixed with sand and water to form a readily pourable suspension, a clay slurry, which is either placed into a trench barrier system or allowed to de-water to create Engineered Soils. The Engineered Soil forms a layer impervious to water and air, therefore by inhibiting both water and oxygen from penetrating through the soil the material. This material can be installed in layers and as a vertical barrier to create a surface barrier containment system. The clay percentage in the clay slurry and Engineered Soils varies depending on site characteristics and desired performance standards. For example Engineered Soils with 1-2% of clay (dry wt.) had a hydraulic conductivity (K) of 10-8 to 10-1 cm/sec. Tests of tailing materials from a kyanite and pyrite mine showed that the clay slurry was effective not only in reducing the permeability of the treated tailings, but also in decreasing their acidity due to the inherent alkalinity of the clay. The untreated tailings had pH values in the range of 2.4 - 3.1; whereas, the effluent from clay and tailings mixtures had pH values in a slightly alkaline range (7.7-7.9). Pug-mills and high volume slurry pumps can be readily adapted for use in constructing and placing caps and creating Engineered Soils. Moreover, material on site or from a local sand supply can be used to create clay slurries and engineered soils. Clay materials used in cap construction are likewise readily available commercially. As a result, the clay slurry system is very cost effective compared to other capping systems, including the commonly used High Density Polyethylene (HDPE) liner systems

96

Linking soil biodiversity and agricultural soil management  

OpenAIRE

Soil biodiversity vastly exceeds aboveground biodiversity, and is prerequisite for ecosystem stability and services. This review presents recent findings in soil biodiversity research focused on interrelations with agricultural soil management. Richness and community structure of soil biota depend on plant biodiversity and vice versa. Soil biota govern nutrient cycling and storage, soil organic matter (SOM) formation and turnover. Agriculture manipulates plants, soils and SOM. With intensific...

Thiele-bruhn, S.; Bloem, J.; Vries, F. T.; Kalbitz, K.; Wagg, C.

2012-01-01

97

Soils - Part 9: Fundamentals of Soil Testing  

Science.gov (United States)

The major emphasis in this lesson is soil testing and understanding the procedures needed to take a representative soil sample. You will understand the term variability, how it affects soil tests, and how a soil test is developed.[This lesson, as well as the other nine lessons in the Soils series, is taken from the "Soils Home Study Course," published in 1999 by the University of Nebraska Cooperative Extension.

98

Soil shrinkage characteristics in swelling soils  

International Nuclear Information System (INIS)

The objectives of this presentation are to understand soil swelling and shrinkage mechanisms, and the development of desiccation cracks, to distinguish between soils having different magnitude of swelling, as well as the consequences on soil structural behaviour, to know methods to characterize soil swell/shrink potential and to construct soil shrinkage curves, and derive shrinkage indices, as well to apply them to assess soil management effects

99

Frozen Soil  

Science.gov (United States)

This Topic in Depth explores the world of frozen soil, including permafrost and tundra. The first site is provided by the Missouri Botanical Gardens Web site, entitled Tundra (1). This kids focused site does a good job of clearly explaining what tundra is, where it's located, and what types of plants and animals are found within tundra areas, as well as offering a photo gallery. The second site, Permafrost (2), is a lesson plan that teaches kids about freezing and thawing soil. Maintained by Newton's Apple television show's companion Web site, teachers are given a complete activity description including vocabulary, additional resources, and instructions for completing the lesson plan. The next site, from the PBS Denali Web site, is another Activity for the Classroom called Permawhat? (3). Objectives of the lesson include having students identify the contents of permafrost found in Alaska's Denali Wilderness, creating their own permafrost in the classroom, comparing summer and winter permafrost, and finally experimenting with the results of warming permafrost. The fourth Web site, A Year in the Life of Your Soil (4), is offered by the University of Minnesota Extension. The single-page site explains what physically happens to soil over a one-year period due to climatic conditions. For example, during the winter, surface soil may freeze and thaw several times, but subsoil only freezes once. Other topics covered include structure, temperature, nutrients, organisms, and plant activity. The next Web site from the US Geological Survey is called Earth Science Photographs (5). The collection of twelve permafrost pictures are from various areas within Alaska, and show some of the interesting effects that the freezing and thawing of soil has on surrounding landscapes. From the National Snow and Ice Data Center, the Permafrost: Insights From a New Northern Hemisphere Map (6) Web site offers some unique information. Visitors will find a description, a map, and a graph that explain the extent of permafrost toward the north pole. The seventh site, Tundra: The Not-So Barren Land (7), is maintained by UC Berkley's Museum of Paleontology. The one-page site explains the general characteristics of a tundra biome and what the difference is between arctic and alpine tundra. The last offering is from the US Fish and Wildlife Service called Active Layer at the Soil Surface (8). The site focuses on the thirteen steps of freezing and thawing that tundra soil experiences. Each step is illustrated and explained from spring to winter, and the entire process is shown as an animation at the bottom of the page.

Brieske, Joel A.

2003-01-01

100

Soil-Net.com  

Science.gov (United States)

Soil-Net.com provides teachers and students ages 5 through 16 (UK Key Stages 1-4) with extensive curriculum-based information about soil, one of our three major natural resources alongside air and water. The site helps users learn about what soil is, the teeming life in soil, the many environmental threats facing soils, and current developments affecting soils-related policymaking and soil science. Soil-Net.com was developed by the National Soil Resources Institute (NSRI) of Cranfield University, UK, the leading institution of soil science and soil-related research in England and Wales.

101

Soil Stabilization Using Lime  

OpenAIRE

Soil stabilization can be explained as the alteration of the soil properties by chemical or physical means in order to enhance the engineering quality of the soil . The main objectives of the soil stabilization is to increase the bearing capacity of the soil ,its resistance to weathering process and soil permeability. The long-term performance of any construction project depends on the soundness of the underlying soils. Unstable soils can create significant problems for pavements or structure...

ANKIT SINGH NEGI; MOHAMMED FAIZAN; DEVASHISH PANDEY SIDDHARTH; REHANJOT SINGH

2013-01-01

102

Soils - Part 2: Physical Properties of Soil and Soil Water  

Science.gov (United States)

This lesson will help you understand the major components of the physical properties of soil. You will learn such terms as texture, aggregation, soil structure, bulk density, and porosity as it relates to soils. You will learn how soil holds and transmits water and cultural practices that enhance or degrade physical properties of the soil.[This lesson, as well as the other nine lessons in the Soils series, is taken from the "Soils Home Study Course," published in 1999 by the University of Nebraska Cooperative Extension.

103

Soil microbiology  

International Nuclear Information System (INIS)

The major areas of soil microbiological and biochemical research which have involved both stable and radioactive isotopes are summarized. These include microbial decomposition of naturally occurring materials, microbial biomass, interactions of plants and microbes, denitrification, mineralization and immobilization of nitrogen and biological nitrogen fixation. (U.K.)

104

Laboratory Assessment of Water Flow Simulator for Porous Parking Lots Reservoir and Soil Layers  

Directory of Open Access Journals (Sweden)

Full Text Available Porous parking lots were implemented to fill the scarcity and strengthen the sustainable development of impervious surfaces in Malaysia to reduce surface runoff. The new methodology proposed enable simulation of reservoir course at stipulated air voids despite details study on water levels and infiltration of porous parking lots system. A uniformly graded choker and reservoir stones functioned as reservoir structure for temporary storm water detention. A specially fabricated water flow simulator allows laboratory simulation of the porous parking lot system. The ability to simulate 1.24 to 59.89 cm h-1 rainfall intensities enable laboratory testing to verify water level and discharge time correlations with different soil infiltration rate at various rainfall intensities. The laboratory tests of vertical infiltration were conducted under conditions of saturated soils. At 59.89 cm h-1 simulated rainfall intensity, the highest water level recorded inside the water flow simulators body without reservoir course is 55 cm from the surface of 0.254 cm h-1 soil infiltration rate. A total of 80.5 h duration was required to completely discharge the stored water between large aggregate particles due to low soil infiltration rate. Utilizing the same laterite soil as bottom layer, the depth increased by approximately 60% after installation of reservoir course with approximately 40% air voids. Over a 60 min duration, the soil with coefficient of permeability equaled to 25.4 cm h-1 had recorded water level 20 cm in height and completely dried within 32.2 min only.

Zul Fahmi Mohamed Jaafar

2011-01-01

105

Soils - Part 4: Soil pH  

Science.gov (United States)

Soil pH is defined and its implications for crop production are described in this lesson. How are soil pH and buffer pH determined? How are these assessments used in lime recommendations? The factors that influence pH variations in soils, the chemistry involved in changing the pH of a soil, and the benefits associated with liming acid soils will be discussed.[This lesson, as well as the other nine lessons in the Soils series, is taken from the "Soils Home Study Course," published in 1999 by the University of Nebraska Cooperative Extension.

106

Soil fertility management: Impacts on soil macrofauna, soil aggregation and soil organic matter allocation.  

OpenAIRE

Maintenance of soil organic matter through integrated soil fertility management is important for soil quality and agricultural productivity, and for the persistence of soil faunal diversity and biomass. Little is known about the interactive effects of soil fertility management and soil macrofauna diversity on soil aggregation and SOM dynamics in tropical arable cropping systems. A study was conducted in a long-term trial at Kabete, Central Kenya, to investigate the effects of organic inputs (...

Ayuke, F. O.; Brussaard, L.; Vanlauwe, B.; Six, J.; Lelei, D. K.; Kibunja, C. N.; Pulleman, M. M.

2011-01-01

107

A parameter study of the two-phase ground water transport in the soil surrounding a growing hemispherical in situ vitrification melt  

International Nuclear Information System (INIS)

Numerical simulation is used to test the effect of several parameters on the water balance and pressure field surrounding a growing hemispherical In Situ Vitrification (ISV) melt. In the current project, a hemispherical annulus of unsaturated soil contained between a growing melt and an impervious wall is modeled. Water vapor vents to atmospheric conditions. The soil is considered a porous media; consequently, fluid velocity can be modeled by Darcy's equation. The capillary pressure and relative permeability are modeled using the equations derived by van Genuchten. The computer model employs a grid which adapts to the transient boundary of the growing melt. The parameters considered include: initial liquid saturation, soil permeability, and melt growth rate. The combined effect of capillary pressure and permeability is also studied. The variation of these parameters in a Hanford soil are studied for their effect on pressure history at the melt interface and total liquid mass history. Transport of heat and mass in the soil is illustrated graphically in terms of the saturation and pressure fields as well as mass flux of liquid and vapor water

108

A parameter study of the two-phase ground water transport in the soil surrounding a growing hemispherical in situ vitrification melt  

Energy Technology Data Exchange (ETDEWEB)

Numerical simulation is used to test the effect of several parameters on the water balance and pressure field surrounding a growing hemispherical In Situ Vitrification (ISV) melt. In the current project, a hemispherical annulus of unsaturated soil contained between a growing melt and an impervious wall is modeled. Water vapor vents to atmospheric conditions. The soil is considered a porous media; consequently, fluid velocity can be modeled by Darcy`s equation. The capillary pressure and relative permeability are modeled using the equations derived by van Genuchten. The computer model employs a grid which adapts to the transient boundary of the growing melt. The parameters considered include: initial liquid saturation, soil permeability, and melt growth rate. The combined effect of capillary pressure and permeability is also studied. The variation of these parameters in a Hanford soil are studied for their effect on pressure history at the melt interface and total liquid mass history. Transport of heat and mass in the soil is illustrated graphically in terms of the saturation and pressure fields as well as mass flux of liquid and vapor water.

Schreiber, W.C. [Univ. of Alabama, Tuscaloosa, AL (United States). Dept. of Mechanical Engineering; Lowery, P.S.; Roberts, J.S. [Pacific Northwest Labs., Richland, WA (United States)

1996-12-31

109

The Twelve Soil Orders  

Science.gov (United States)

At this website, the University of Idaho provides information and images of the twelve classifications of soil taxonomy. After learning about the soils, users can find world and United States maps illustrating where each are located. The website offers downloadable documents of the soil taxonomy text, maps and errata sheet for the second edition of _Soil Taxonomy, A Basic System of Soil Classification for Making and Interpreting Soil Surveys_. Students and educators can also find a link to the World Reference Base for Soil Resources. This website is tremendously helpful for anyone involved in soil science or soil mapping.

110

Soil Core Sampling  

Science.gov (United States)

Students learn about one method used in environmental site assessments. They practice soil sampling by creating soil cores, studying soil profiles and characterizing soil profiles in borehole logs. They use their analysis to make predictions about what is going on in the soil and what it might mean to an engineer developing the area.

Integrated Teaching and Learning Program,

111

Soil compaction and soil tillage - studies in agricultural soil mechanics  

OpenAIRE

This thesis deals with various aspects of soil compaction due to agricultural field traffic, the draught force requirement of tillage implements and soil structures produced by tillage. Several field experiments were carried out to study the mechanical impact of agricultural machines. It was shown that the stress interaction from the different wheels in dual and tandem wheel configurations is small and these wheels can be considered separate wheels with regard to soil stress. Hence, soil stre...

Keller, Thomas

2004-01-01

112

Soil Science - 9th Grade  

Science.gov (United States)

What are four different soils in Alabama, and what are the charastics First, Read the Soil Regions page. Soil Regions Second, read the page discussing soil types. Read about the first four soil types. Soil Types Third, Please read the information relating to Marine Sediment soils. In this case, you will be learning about the Dothan variety of Marine Sediment soil. Marine Sediment Soils (Dothan Soils) Here is some useful information on Granite Soils, ...

Allred, Mr.

2011-04-06

113

Does Soil Disturbance Affect Soil Phosphorus Fractions?  

Directory of Open Access Journals (Sweden)

Full Text Available Increased turnover of organic matter as a result of soil disturbance (e.g. by soil tillage is described in principle, but the direct influence of soil disturbance on soil P turnover especially for organic farming systems has not been sufficiently proven. The objective of the study was to evaluate the short term effect of soil disturbance on different soil P fractions in a soil shaking experiment. Four soils were incubated for 10 days in the dark with three different disturbance treatments: 1 no disturbance, 2 overhead shaking for 2 h at the beginning of the experiment and 3 continuous overhead shaking at 5 r. p. m. The four investigated soils were: 1 a silty loam soil with long term bio-compost application and 2 the corresponding soil without bio-compost application, 3 a long-term organically managed clay loam soil and 4 a clay loam soil with long time application of pig manure, all not and from Baden-Wrttemberg, Germany. We determined NaHCO3-, NaOH- and H2SO4-extractable inorganic and organic P fractions (Pi and Po, resp. in a sequential extraction. Furthermore, the potentially plant available P as Calcium-acetate-lactate-extractable P (CAL-P and P extractable by electro-ultra-filtration (EUF-P, and aqua regia extractable total P (PT were determined. Furthermore, we determined microbial biomass carbon (MBC, nitrogen (MBN and phosphorus (MBP, and acid phosphatase activity in soil. The organically managed soil had the highest PT contents (1300 mgkg-1. The soil with pig manure application had the smallest potentially labile P fractions (NaHCO3-Pi and -Po and NaOH-Pi. The ecologically managed soil had the biggest organic P fractions (114 mgkg-1 NaHCO3-Po and 463 mgkg-1 NaOH-Po, but, this soil was the lowest in CAL-P (5 mgkg-1. Short term soil disturbance had effects on labile organic P fractions of two of the four analyzed soils, but inorganic P was rather unaffected. In the compost amended COMP(+ soil, there was an incorporation of P from the less available NaOH-P fractions into the more available NaHCO3-Po fraction. However, if taking all investigated soils and treatments into account, the effects of soil disturbance were limited and not consistent.

Yonathan D. Redel

2013-10-01

114

Teaching Science with Soil.  

Science.gov (United States)

Prepared primarily for junior high school students and utilizing an integrated science approach, this manual offers activities for examining the ecosystem and environmental problems. With organic aspects of soils as the main subject field, it includes study of soil formation, soil fertility, soil contamination, and edaphic relationships. Most of

Schatz, Albert; Kriebs, Jean Oak

115

MILESTONES IN SOIL PHYSICS  

Science.gov (United States)

This special issue of Soil Science celebrates the enormous accomplishments made during the past century or more in the field of soil science, including some of the key articles published in Soil Science during its 90 years of existence. In this article, we focus on the contributions in soil physic...

116

Modeling soil freezing dynamics  

Science.gov (United States)

Seasonally frozen soil strongly influences runoff and erosion on large areas of land around the world. In many areas, rain or snowmelt on seasonally frozen soil is the single leading cause of severe runoff and erosion events. As soils freeze, ice blocks the soil pores, greatly diminishing the permea...

117

Fundamentals of soil science  

Science.gov (United States)

This study guide provides comments and references for professional soil scientists who are studying for the soil science fundamentals exam needed as the first step for certification. The performance objectives were determined by the Soil Science Society of America's Council of Soil Science Examiners...

118

Soil Properties and Geomorphology  

Science.gov (United States)

To prepare for this exercise, the students have been lectured on soil formation and on a field trip, described a simple soil within loess. Here, the students use data collected from a chronosequence to compare the relative age and amount of soil formation on a series of fluvial terraces. The students are to insert the data into a graphic program and generate specific graphs of soil properties. The students then interpret the amount of soil formation compared to the relative age of the fluvial terraces. Finally, the students assess how the 5 soil forming factors (climate, organisms, relief, parent material, and time) influenced soil formation in this setting. Designed for a geomorphology course

Sweeney, Mark

119

Soil physical properties affecting soil erosion in tropical soils  

International Nuclear Information System (INIS)

The total vegetated land area of the earth is about 11,500 hectare. Of this, about 12% is in South America. Of this, about 14% is degraded area. Water erosion, chemical degradation, wind erosion, and physical degradation have been reported as main types of degradation. In South America water erosion is a major process for soil degradation. Nevertheless, water erosion can be a consequence of degradation of the soil structure, especially the functional attributes of soil pores to transmit and retain water, and to facilitate root growth. Climate, soil and topographic characteristics determine runoff and erosion potential from agricultural lands. The main factors causing soil erosion can be divided into three groups: Energy factors: rainfall erosivity, runoff volume, wind strength, relief, slope angle, slope length; Protection factors: population density, plant cover, amenity value (pressure for use) and land management; and resistance factors: soil erodibility, infiltration capacity and soil management. The degree of soil erosion in a particular climatic zone, with particular soils, land use and socioeconomic conditions, will always result from a combination of the above mentioned factors. It is not easy to isolate a single factor. However, the soil physical properties that determine the soil erosion process, because the deterioration of soil physical properties is manifested through interrelated problems of surface sealing, crusting, soil compaction, poor drainage, impeded root growth, excessive runoff and accelerated erosion. When an unprotected soil surface is exposed to the direct impact of raindrops it can produce different responses: Production of smaller aggregates, dispersed particles, particles in suspension and translocation and deposition of particles. When this has occurred, the material is reorganized at the location into a surface seal. Aggregate breakdown under rainfall depends on soil strength and a certain threshold kinetic energy is needed to start detachment. Studies on necessary kinetic energy to detach one kilogram of sediments by raindrop impact have shown that the minimum energy is required for particles of 0.125 mm. Particles between 0.063 to 0.250 mm are the most vulnerable to detachment. This means that soils with high content of particles into vulnerable range, for example silty loam, loamy, fine sandy, and sandy loam are the most susceptible soils to detachment. Many aspects of soil behaviour in the field such as hydraulic conductivity water retention, soil crusting, soil compaction, and workability are influenced strongly by the primary particles. In tropical soils also a negative relation between structure stability and particles of silt, fine sand and very fine sand has been found, this is attributed to low cohesiveness of these particles. The ability of a structure to persist is known as its stability. There are two principal types of stability: the ability of the soil to retain its structure under the action of water, and the ability of the soil to retain its structure under the action of external mechanical stresses. (e.g. by wheels). Both types of stability are related with susceptibility to erosion

120

Soil Erosion Studies  

OpenAIRE

Soil erosion affects a large part of the Earth surface, and accelerated soil erosion is recognized as one of the main soil threats, compromising soil productive and protective functions. The land management in areas affected by soil erosion is a relevant issue for landscape and ecosystems preservation. In this book we collected a series of papers on erosion, not focusing on agronomic implications, but on a variety of other relevant aspects of the erosion phenomena. The book is divided into th...

Godone, Danilo Francesco; Stanchi, Silvia

2011-01-01

121

Electrical properties of soils  

Science.gov (United States)

In this study, thorough analysis is conducted for soil electrical properties, i.e. electrical resistivity, conductivity, and potential. Soil electrical properties are the parameters of natural and artificially created electrical fields in soils and influenced by distribution of mobile electrical charges, mostly inorganic ions, In soils. Distributions of electrical charges and properties in various soil profiles were shown to be results of the soil-forming processes. Soil properties influencing the density of mobile electrical charges were found to be exponentially related with electrical resistivity and potential based on Boltzmann's law of statistical thermodynamics. Relationships were developed between electrical properties and other soil physical and chemical properties, such as texture, stone content, bulk density, water content, cation exchange capacity, salinity, humus content, and base saturation measured in-situ and in soil samples. Geophysical methods of vertical electrical sounding, four-electrode probe, non-contact electromagnetic profiling, and self-potential were modified for measuring soil electrical properties and tested in different soil studies. The proposed methods are extremely efficient, reliable, and non-disturbing. Compared with conventional methods of soil analysis, the electrical geophysical methods allowed evaluating groundwater table, salt content, depth and thickness of soil horizons, Polluted or disturbed layers in soil profiles, and stone content with an estimation error soil genesis, precision agriculture, and environmental engineering. The applications of the methods included studying soil water retention, compaction, and soil morphology; mapping soil spatial variability within fields, catenas, or landscapes; locating genetic horizons, compacted or disturbed layers, hydrocarbon pollutants, stones, and groundwater tables in soil profiles; and monitoring soil drying or freezing.

Pozdnyakova, Larisa A.

122

Soil mapping in Spain  

OpenAIRE

The first soil maps representing Spain date from the beginning of the century: the Universal Soil Map of Glinka and that prepared by Sibirtzev and Ramman (Mudarra 1989). The first research work carried out on Spanish soil however must be attributed to E. Huguet del Villar, who was already pioneering soil surveys of the Iberian Peninsula in 1927 on the occasion of the first Intemational Soil Science Congress held in Washington (Huguet del Villar 1927). At that time, he collaborated on the worl...

Iba?n?ez, J. J.; Rubio, J. L.; Lo?pez-lafuente, A.; Monturiol, F.

1991-01-01

123

Atlas of soil reflectance properties  

Science.gov (United States)

A compendium of soil spectral reflectance curves together with soil test results and site information is presented in an abbreviated manner listing those soil properties most important in influencing soil reflectance. Results are presented for 251 soils from 39 states and Brazil. A narrative key describes relationships between soil parameters and reflectance curves. All soils are classified according to the U.S. soil taxonomy and soil series name for ease of identification.

Stoner, E. R.; Baumgardner, M. F.; Biehl, L. L.; Robinson, B. F.

1979-01-01

124

Soil hydraulic properties of Cuban soils  

International Nuclear Information System (INIS)

Because soil hydraulic properties are indispensable for determining soil water retention and soil water movement, their input for deterministic crop simulation models is essential. From these models is possible to access the effect of the weather changes, soil type or different irrigation schedules on crop yields. With these models, possibilities are provided to answer questions regarding virtual 'what happen if' experiments with a minimum of fieldwork. Nevertheless, determining soil hydraulic properties can be very difficult owing to unavailability of necessary equipment or the lack of personal with the proper knowledge for those tasks. These deficiencies are a real problem in developing countries, and even more so when there is not enough financial possibilities for research work. This paper briefly presents the way these properties have been accessed for Cuban soils, which methods have been used and the work now in progress. (author)

125

Mass Transport within Soils  

Energy Technology Data Exchange (ETDEWEB)

Contaminants in soil can impact human health and the environment through a complex web of interactions. Soils exist where the atmosphere, hydrosphere, geosphere, and biosphere converge. Soil is the thin outer zone of the earth's crust that supports rooted plants and is the product of climate and living organisms acting on rock. A true soil is a mixture of air, water, mineral, and organic components. The relative proportions of these components determine the value of the soil for agricultural and for other human uses. These proportions also determine, to a large extent, how a substance added to soil is transported and/or transformed within the soil (Spositio, 2004). In mass-balance models, soil compartments play a major role, functioning both as reservoirs and as the principal media for transport among air, vegetation, surface water, deeper soil, and ground water (Mackay, 2001). Quantifying the mass transport of chemicals within soil and between soil and atmosphere is important for understanding the role soil plays in controlling fate, transport, and exposure to multimedia pollutants. Soils are characteristically heterogeneous. A trench dug into soil typically reveals several horizontal layers having different colors and textures. As illustrated in Figure 1, these multiple layers are often divided into three major horizons: (1) the A horizon, which encompasses the root zone and contains a high concentration of organic matter; (2) the B horizon, which is unsaturated, lies below the roots of most plants, and contains a much lower organic carbon content; and (3) the C horizon, which is the unsaturated zone of weathered parent rock consisting of bedrock, alluvial material, glacial material, and/or soil of an earlier geological period. Below these three horizons lies the saturated zone - a zone that encompasses the area below ground surface in which all interconnected openings within the geologic media are completely filled with water. Similarly to the unsaturated zone with three major horizons, the saturated zone can be further divided into other zones based on hydraulic and geologic conditions. Wetland soils are a special and important class in which near-saturation conditions exist most of the time. When a contaminant is added to or formed in a soil column, there are several mechanisms by which it can be dispersed, transported out of the soil column to other parts of the environment, destroyed, or transformed into some other species. Thus, to evaluate or manage any contaminant introduced to the soil column, one must determine whether and how that substance will (1) remain or accumulate within the soil column, (2) be transported by dispersion or advection within the soil column, (3) be physically, chemically, or biologically transformed within the soil (i.e., by hydrolysis, oxidation, etc.), or (4) be transported out of the soil column to another part of the environment through a cross-media transfer (i.e., volatilization, runoff, ground water infiltration, etc.). These competing processes impact the fate of physical, chemical, or biological contaminants found in soils. In order to capture these mechanisms in mass transfer models, we must develop mass-transfer coefficients (MTCs) specific to soil layers. That is the goal of this chapter. The reader is referred to other chapters in this Handbook that address related transport processes, namely Chapter 13 on bioturbation, Chapter 15 on transport in near-surface geological formations, and Chapter 17 on soil resuspention. This chapter addresses the following issues: the nature of soil pollution, composition of soil, transport processes and transport parameters in soil, transformation processes in soil, mass-balance models, and MTCs in soils. We show that to address vertical heterogeneity in soils in is necessary to define a characteristic scaling depth and use this to establish process-based expressions for soil MTCs. The scaling depth in soil and the corresponding MTCs depend strongly on (1) the composition of the soil and physical state of the soil, (2) the chemical and p

McKone, Thomas E.

2009-03-01

126

Soil washing technology evaluation  

International Nuclear Information System (INIS)

Environmental Restoration Engineering (ERE) continues to review innovative, efficient, and cost effective technologies for SRS soil and/or groundwater remediation. As part of this effort, this technical evaluation provides review and the latest information on the technology for SRS soil remediation. Additional technology evaluation reports will be issued periodically to update these reports. The purpose of this report is to review the soil washing technology and its potential application to SRS soil remediation. To assess whether the Soil Washing technology is a viable option for SRS soil remediation, it is necessary to review the technology/process, technology advantages/limitations, performance, applications, and cost analysis

127

Gypseous soils and the universal soil taxonomic system  

OpenAIRE

This presentation focus on three aspects of gypseous soils: 1) Soil Taxonomy as a language; 2) The uniqueness of gypseous soils; 3) Why their taxa and the terms used for other mineral soils should be applied with caution.

Herrero Isern, Juan

2012-01-01

128

Tillage effects on soil respiration in Swedish arable soils  

OpenAIRE

The amount of carbon (C) present in soil is greater than the sum of C present in terrestrial vegetation and the atmosphere combined. Small changes in soils can therefore affect atmospheric CO? levels and ultimately the global climate. Soil C is also one of the main soil properties involved in several soil functions critical for soil productivity. Mechanical disturbance of the soil, e.g. through tillage, can influence soil C and has been the focus...

Kainiemi, Veera

2014-01-01

129

Understanding Soil Change  

Science.gov (United States)

Across the world, soils are managed with an intensity and at a geographic scale never before attempted, yet we know remarkably little about how and why managed soils change through time. Understanding Soil Change explores a legacy of soil change in southeastern North America, from the acidic soils of primary hardwood forests that covered the region until about 1800, through the marked transformations affected by long-cultivated cotton, to contemporary soils of rapidly growing and intensively managed pine forests. These well documented records significantly enrich the science of ecology and pedology, and provide valuable lessons for land management throughout the world. The book calls for the establishment of a global network of soil-ecosystem studies, like the invaluable Calhoun study on which the book is based, to provide further information on sustainable land management, vital as human demands on soil continue to increase.

Richter, Daniel D., Jr.; Markewitz, Daniel

2001-06-01

130

Remediation of Contaminated Soils  

International Science & Technology Center (ISTC)

Development of Methods for Remediation of Soils with Increased Contents of Heavy Metals, Radionuclides and Improvement of Soils for Ecologically Clean Agricultural Production Systems Taking into Account the Population Health Indicators

131

Soil Litter: Temperate Zones  

Science.gov (United States)

This two-minute radio program focuses on why temperate soils harbor more biodiversity than do tropical soils. The guest on the program, a soil biologist, explains that cooler temperatures and large-scale disturbances have promoted the evolution of more soil-dwelling species in temperate areas. The program, part of the Pulse of the Planet radio show, is available here in text and audio formats. Copyright 2005 Eisenhower National Clearinghouse

Planet, Pulse O.

2006-06-23

132

What is Soil Liquefaction?  

Science.gov (United States)

This reference explains the phenomenon of soil liquefaction, a common cause of damage to man-made structures that occurs during earthquakes. Students can read an explanation of how the water in wet soils exerts a pressure on the soil particles that influences how tightly the particles themselves are pressed together, causing the soil to lose strength. The text is accompanied by animations that show the phenomenon in action.

133

Technogenic Soils of Poland  

OpenAIRE

In recent years, urban soils have been extensively researched. The growing interest in the related issues contributes to better understanding of the soil cover diversity in the cities, identification of changes and threats resulting from urbanization and industrialisation. This book presents the state of the art of knowledge about diverse technogenic soils in Poland. It includes many examples of urban soil studies conducted in miscellaneous Polish scientific centres. The presented issues conc...

Charzyn?ski, Przemys?aw; Hulisz, Piotr; Bednarek, Renata

2013-01-01

134

A soil science renaissance  

OpenAIRE

The renaissance was an intellectually-rich period following a period of stasis in the medieval period. Something analogous appears to be currently taking place in soil science where novel approaches to thought are combined with a revival of ideas from the past. Renewed interest in agriculture (food, feed, fuel) and numerous publications have brought soils back onto the global research agenda. The need for up-to-date and fine resolution soil information and the revival of soil research has bee...

Hartemink, A. E.

2008-01-01

135

Soil function and "malfunction"  

OpenAIRE

Most of the scientists define soil from an agronomic point of view as the natural system delegated to sustain plant
growth and agricultural productions on the whole. In this paper soil importance, even in environmental and social
terms, is pointed out, considering soil as a natural body with its own functional characteristics, regardless of
its agronomic role and productive ability. Some studies show that soil acts a...

Elio Coppola; Andrea Buondonno

2008-01-01

136

CONSIDERATIONS ON URBAN SOILS  

OpenAIRE

Urban soil is an material that has been manipulated, disturbed or transported by mans activities in the urban environment and is used as a medium for plant growth and for constructions. The physical, chemical, and biological properties are generally less favorable as a rooting medium than soil found on the natural landscape. The main characteristics of urban soils are: great vertical and spatial variability; modified soil structure leading to compaction; presence of a surface crust; modifi...

Radu Lacatusu

2005-01-01

137

Iodine dynamics in soils  

OpenAIRE

The principal aim of this investigation was to understand the transformation and reaction kinetics of iodide and iodate added to soil in relation to soil properties. In addition, to integrate the data into a predictive model of iodide and iodate sorption kinetics parameterised by soil properties. Solid phase fractionation coupled with solution phase speciation (HPLC-ICPMS) was used to follow the assimilation of 129I- and 129IO3- spikes into steady state soil microcosms. The ext...

Shetaya, W. H.; Young, S. D.; Watts, M. J.; Ander, E. L.; Bailey, E. H.

2012-01-01

138

Gravimetric Soil Moisture Protocols  

Science.gov (United States)

The purpose of this resource is to measure soil water content by mass. Students collect soil samples with a trowel or auger and weigh them, dry them, and then weigh them again. The soil water content is determined by calculating the difference between the wet sample mass and the dry sample mass.

The GLOBE Program, University Corporation for Atmospheric Research (UCAR)

2003-08-01

139

Cleaning soil without incineration  

International Nuclear Information System (INIS)

This article addresses the clean up of contaminated soil without burning. The topics of the article include the problems associated with incineration at depths requiring excavation, a description of the contaminated site, pilot testing of the remediation soil washing process, full-scale cleanup, a description of the soil separation and washing process

140

Soil Use and Management  

Science.gov (United States)

This site is part of the US Department of Agriculture\\'s Natural Resource\\'s Conservation Service, providing state-of-the-art soil survey technology, standards, data, and expertise. This site covers soil quality, hydric and urban soils, facts and figures for the United States, and a number of world, national and thematic maps.

141

Neptunium in soils  

International Nuclear Information System (INIS)

A bibliography and compiled data are presented on neptunium isotopes in different soil types, especially 237Np. After surveying soil chemistry and sorption behaviour of a variety of rock types and soil types like loams, sands and clays, the mobility of neptunium is considered. (G.J.P.)

142

Tropical Soil Chemistry  

DEFF Research Database (Denmark)

A new book that is particularly relevant as tropical countries experience increased pressure on land resources to improve agricultural production. To ensure sustainable land use, the potentials and limitations of different kinds of tropical soils must be known in relation to crop production and environmental protection. Tropical Soil Chemistry by Ole K. Borggaard provides an overview of the composition, occurrence, properties, processes, formation, and environmental vulnerability of various tropical soil types (using American Soil Taxonomy for classification). The processes and the external factors that affect soil processes are the same in tropical soils as in temperate region soils, but because of high temperature year round and occurrence in very stable landscapes, some (but not all) tropical soils possess special composition and properties. These features are highlighted in the book, and general soil chemical issues are also presented to assess when, why, and how tropical soils differ from soils in other regions. This knowledge can help agricultural specialists in the tropics establish sustainable crop production. Readers are assumed to be familiar with basic chemistry, physics, and mathematics at a level corresponding to introductory university courses. Knowledge of fundamental geology, geography, and soil science is also needed. The book can be purchased from the Department.

Borggaard, Ole K.

2008-01-01

143

Experimental unsaturated soil mechanics  

CERN Document Server

In this general report, experimental systems and procedures of investigating the hydro-mechanical behaviour of unsaturated soils are presented. The water retention properties of unsaturated soils are commented and linked to various physical parameters and properties of the soils. Techniques of controlling suction are described together with their adaptation in various laboratory testing devices. Some typical features of the mechanical behaviour of unsaturated soils are presented within an elasto-plastic framework. An attempt to describe the numerous and significant recent advances in the investigation of the behaviour of unsaturated soils, including the contributions to this Conference, is proposed.

Delage, Pierre

2008-01-01

144

Soil Particle Density Protocol  

Science.gov (United States)

The purpose of this resource is to measure the soil particle density of each horizon in a soil profile. Students weigh a sample of dry, sieved soil from a horizon, mix it with distilled water and then boil the mixture to remove any air. The mixture cools for a day and then students add water until the volume of the mixture is 100 mL. Students measure the temperature and mass of the final mixture and use the Soil Particle Density Data Sheet to calculate the soil particle density. Three samples should be measured for each horizon.

The GLOBE Program, University Corporation for Atmospheric Research (UCAR)

2003-08-01

145

Bioindication with soil microfauna  

International Nuclear Information System (INIS)

The state of a soil can be characterised through its inhabitant micro-, meso-, and macrofauna. For an appropriate assessment of soil quality at least one representative of each of these size categories should be studied (e.g. testacea, mites, earthworms). This contribution summarizes the insights gained from microscopic soil fauna in this context. The following practical examples are discussed: pesticides, organic and artificial fertilisers, soil compaction, ecological and conventional farming, recolonisation. The 'weighted cenosis index' represents a quantitative measure for the influence of anthropogenic activity on a soil. (orig.)

146

[Applications of soil metaproteomics in soil pollution assessment: a review].  

Science.gov (United States)

Soil microbial indicator is one of the important biological indicators in evaluating the extent of soil contamination. In recent years, with the development of molecular biology, many studies have focused on the ecological functions of soil microorganisms by using metagenomics, metatranscriptome and metaproteomics. Relative to metagenomics and metatranscriptome, soil metaproteomics aims to investigate the spatial and temporal changes of the proteins extracted from soil as well as the functional components of soil microbial genomic expression products, which is more conclusive to explore the ecological functions of soil microbes and their roles in soil pollutants transportation and transformation. Therefore, soil metaproteomics has great potential in soil pollution assessment. Currently, soil metaproteomics is still at its infancy stage, while soil protein extraction method is one of the key factors restraining the potential application of soil metaproteomics. In this paper, the advantages and disadvantage of soil metaproteomics in soil pollution assessment were reviewed, with the focus on the comparison of different soil protein extraction methods. In combining with case studies, the feasibility and limits of soil proteins as an indicator for soil pollution assessment were analyzed. In addition, the future research perspectives on the development of soil metaproteomics were discussed. PMID:23359959

Zhang, Xi; Li, Feng; Liu, Ting-Ting; Chen, Ying-Xu

2012-10-01

147

Soil-dithiocarbamate interactions  

International Nuclear Information System (INIS)

Soil is the ultimate repository of the pesticides applied for the control of plant pests and diseases. A variety of interactions like leaching, adsorption, chemical and microbial degradation etc take place between soil and pesticide. Results on work on two dialkyldithiocarbamates viz. thiram (tetramethylthiuram disulfide) and ziram (zinc dimethyldithiocarbamate) with respect to above interactions in soil are discussed and summarised. 35S-labelled thiram and ziram were used in the studies. (author)

148

Soil Classification Using GATree  

OpenAIRE

This paper details the application of a genetic programming framework for classification of decision tree of Soil data to classify soil texture. The database contains measurements of soil profile data. We have applied GATree for generating classification decision tree. GATree is a decision tree builder that is based on Genetic Algorithms (GAs). The idea behind it is rather simple but powerful. Instead of using statistic metrics that are biased towards specific trees we use a...

Bhargavi, P.; Jyothi, Dr S.

2010-01-01

149

Soil physics and agriculture  

International Nuclear Information System (INIS)

The approach that integrates knowledge is very important in Agriculture, including farmers, extensionists, researchers and professors. The specialists, including the soil physicists, must have a global view of the crop production system. Therefore, their expertise can be useful for the society. The Essence of scientific knowledge is its practical application. The soil physics is a sub area of Agronomy. There are many examples of this specific subject related to Agriculture. This paper will focus, in general, the following cases: (i) erosion, environmental pollution and human health, (ii) plant population and distribution, soil fertility, evapo-transpiration and soil water flux density, and (iii) productivity, effective root depth, water deficit and yield

150

The Living Soil  

Science.gov (United States)

Soil is home to vast numbers of organisms, and even small sections of earth teem with a diverse array of life. This Topic in Depth takes a closer look at the world beneath our feet through the lens of soil biologists and ecologists. The first website (1) provides information about the activities of a Natural Environment Research Council-supported research program "on the biological diversity of soil biota and the functional roles played by soil organisms in key ecological processes." The second site (2) contains information about several research projects of the Ecology of Soil Organisms Theme Group at Wageningen University and Research Centre. The Theme Group studies "soil organisms at the population, community, and ecosystem level, to ultimately increase understanding of the role of soil organisms." The third site (3) contains a list of publications spanning the past fifteen years from members of the Soil Ecology Group at the University of Jyv'skyl". The site also provides basic information about group members, and concise descriptions of current research projects. From the USDA Natural Resources Conservation Service, the fourth website (4) contains an online version of the _Soil Biology Primer_, "an introduction to the living component of soil and how it contributes to agricultural productivity, and air and water quality. The Primer includes units describing the soil food web and its relationship to soil health, and units about bacteria, fungi, protozoa, nematodes, arthropods, and earthworms." The online version of the Primer contains the entire text of the original published version, but is missing some useful soil organism images. The fifth site (5) links to sixteen movies relating to different aspects of soil biology such as nematodes, mites, springtails, and protozoa. The movies were all produced by Dr. Thomas E. Loynachan, a Professor of Agronomy and Microbiology at Iowa State University. Finally, Soils Are Alive (6) was developed by Professor Lyn Abbot of the University of Western Australia and Jen Slater, a qualified secondary school science teacher. This website contains informative, concise sections addressing Soil Biology, Biological Processes, Living Components, and Ecosystem Management.

151

Radioisotopes in soil science  

International Nuclear Information System (INIS)

Soils form a thin veneer of the Earth that sustain the entire flora and fauna of the terra firma. To that extent the soil as a natural resource is very precious and needs to be managed in a sustainable manner. The fate of degradation of pesticides in soil and build-up of heavy metals in the overall biosafety scenario is also studied gainfully using radioisotopes. Radioisotopes are a very potent tool in the hands of the Soil Scientists, perhaps, the most important among the peaceful applications in service of the mankind

152

Earthworms and Soil Pollutants  

Directory of Open Access Journals (Sweden)

Full Text Available Although the toxicity of metal contaminated soils has been assessed with various bioassays, more information is needed about the biochemical responses, which may help to elucidate the mechanisms involved in metal toxicity. We previously reported that the earthworm, Eisenia fetida, accumulates cadmium in its seminal vesicles. The bio-accumulative ability of earthworms is well known, and thus the earthworm could be a useful living organism for the bio-monitoring of soil pollution. In this short review, we describe recent studies concerning the relationship between earthworms and soil pollutants, and discuss the possibility of using the earthworm as a bio-monitoring organism for soil pollution.

Kazuyoshi Tamae

2011-11-01

153

Shrinking Behaviour of Badland Soil Under Different Soil Covers  

OpenAIRE

Indicators used to estimate the soil structure stability facing erosion are the basis of major indicators of soil quality, and their behaviour is affected by permanent soil properties, vegetation and management. The relation between the pore-volume fraction occupied by water and the pore size distribution in clay soils is studied by the shrinkage curve describing clay soil porosity dynamics as a function of soil moisture. The aim of this work is to study the shrinking behaviour of the surface...

Michele Perniola; Mariana Amato; Stella Lovelli; Teodoro Di Tommaso

2009-01-01

154

How Can Soil Electrical Conductivity Measurements Control Soil Pollution?  

OpenAIRE

Soil pollution results from the build up of contaminants, toxic compounds, radioactive materials, salts, chemicals and cancer-causing agents. The most common soil pollutants are hydrocarbons, heavy metals (cadmium, lead, chromium, copper, zinc, mercury and arsenic), herbicides, pesticides, oils, tars, PCBs and dioxins. Soil Electrical Conductivity (EC) is one of the soil physical properties w hich have a good relationship with the other soil characteristics. As measuring soil electrical condu...

Mohammad Reza; Sharifi, R. Alimardani And A.

2010-01-01

155

Using Soil Color/Reflectance in Predicting Soil Properties  

OpenAIRE

Correlations of soil components, value and chroma with selected soil physical and chemical properties from 563 surface soil samples from the Great Plains area, USA revealed that clay, organic carbon, cation exchange capacity and water held at 1/3 and 15 bars were most highly correlated. Regression correlations based on these soil color components were developed to estimate many soil properties. Surface soil samples from two study sites located in Boone County, Missouri, USA were measured b...

Johannsen, Chris J.; Dacosta, Liovando M.

1980-01-01

156

Microbial diversity as soil quality indicator in agricultural soils  

OpenAIRE

Soil quality is the capacity of a specific kind of soil to function, within natural or managed ecosystem boundaries, to sustain plant and animal productivity, maintain or enhance water and air quality, and support human health and habitation. Soil organisms are assumed to be directly responsible for soil ecosystem processes, especially the decomposition of soil organic matter and the cycling of nutrients. Since soil quality is strongly influenced by microbe-mediated processes, and funct...

Chiurazzi, Mario

2008-01-01

157

Estimating soil water retention using soil component additivity model  

Science.gov (United States)

Soil water retention is a major soil hydraulic property that governs soil functioning in ecosystems and greatly affects soil management. Data on soil water retention are used in research and applications in hydrology, agronomy, meteorology, ecology, environmental protection, and many other soil-related fields. Soil organic matter content and composition affect both soil structure and adsorption properties; therefore water retention may be affected by changes in soil organic matter that occur because of both climate change and modifications of management practices. Thus, effects of organic matter on soil water retention should be understood and quantified. Measurement of soil water retention is relatively time-consuming, and become impractical when soil hydrologic estimates are needed for large areas. One approach to soil water retention estimation from readily available data is based on the hypothesis that soil water retention may be estimated as an additive function obtained by summing up water retention of pore subspaces associated with soil textural and/or structural components and organic matter. The additivity model and was tested with 550 soil samples from the international database UNSODA and 2667 soil samples from the European database HYPRES containing all textural soil classes after USDA soil texture classification. The root mean square errors (RMSEs) of the volumetric water content estimates for UNSODA vary from 0.021 m3m-3 for coarse sandy loam to 0.075 m3m-3 for sandy clay. Obtained RMSEs are at the lower end of the RMSE range for regression-based water retention estimates found in literature. Including retention estimates of organic matter significantly improved RMSEs. The attained accuracy warrants testing the 'additivity' model with additional soil data and improving this model to accommodate various types of soil structure. Keywords: soil water retention, soil components, additive model, soil texture, organic matter.

Zeiliger, A.; Ermolaeva, O.; Semenov, V.

2009-04-01

158

Relaxometry in soil science  

Science.gov (United States)

NMR relaxometry is a sensitive, informative and promising method to study pore size distribution in soils as well as many kinds of soil physicochemical processes, among which are wetting, swelling or changes in the macromolecular status. Further, it is a very helpful method to study interactions between molecules in soil organic matter and it can serve to study the state of binding of water or organic chemicals to soil organic matter. The method of Relaxometry excite the nuclei of interest and their relaxation kinetics are observed. The relaxation time is the time constant of this first order relaxation process. Most applications of relaxometry concentrate on protons, addressing water molecules or H-containing organic molecules. In this context, 1H-NMR relaxometry may be used as an analysis method to determine water uptake characteristics of soils, thus gaining information about water distribution and mobility as well as pore size distribution in wet and moist samples. Additionally, it can also serve as a tool to study mobility of molecular segments in biopolymers. Principally, relaxometry is not restricted to protons. In soil science, relaxometry is also applied using deuterium, xenon and other nuclei to study pore size distribution and interactions. The relaxation time depends on numerous parameters like surface relaxivity, diffusion and interactions between nuclei as well as between nuclei and the environment. One- and two-dimensional methods address the relation between relaxation time and diffusion coefficients and can give information about the interconnectivity of pores. More specific information can be gained using field cycling techniques. Although proton NMR relaxometry is a very promising method in soil science, it has been applied scarcely up to now. It was used to assess changes in molecular rigidity of humic substances. A very recent study shows the potential of NMR relaxometry to assess the pore size distribution of soils in a fast and non-destructive way. Recent studies investigated wetting and swelling processes in soil samples, as well as the formation of microbial biofilms in soil the formation. This contribution gives an overview of current applications and the potential of NMR relaxometry in soil science with special emphasis on proton NMR relaxometry. References Bird, N.R.A., Preston, A.R., Randall, E.W., Whalley, W.R. & Whitmore, A.P. 2005. Measurement of the size distribution of water-filled pores at different matric potentials by stray field nuclear magnetic resonance. 56, 135-143. Bryar, T.R. & Knight, R.J. 2002. Sensitivity of Nuclear Magnetic Resonance Relaxation Measurements to Changing Soil Redox Conditions. Geophysical Research Letters, 29, 50/1-50/4. Conte, P., Spaccini, R. & Piccolo, A. 2006. Advanced CPMAS-13C NMR techniques for molecular characterization of size-separated fractions from a soil humic acid. Analytical and Bioanalytical Chemistry, 386, 382-390. Gunasekara, A.S., Simpson, M.I. & Xing, B. 2003. Identification and characterization of sorption domains in soil organic matter using strucuturally modified humic acids. Environmental Science & Technology, 37, 852-858. Jaeger, F., Grohmann, E., Boeckelmann, U. & Schaumann, G.E. 2006. Microbial effects on 1H NMR Relaxometry in soil samples and glass bead reactors. In Humic Substances - Linking Structure to Functions. Proceedings of the 13th Meeting of the International Humic Substances Societyin Karlsruhe eds. F.H. Frimmel & G. Abbt-Braun), pp. 929-932. Universitt Karlsruhe, Karlsruhe. Hurra, J. & Schaumann, G.E. 2007. Hydration kinetics of wettable and water repellent soil samples. Soil Science Society of America Journal, 71, 280-288. Jaeger, F., Grohmann, E. & Schaumann, G.E. 2006. 1H NMR Relaxometry in natural humous soil samples: Insights in microbial effects on relaxation time distributions. Plant and Soil, 280, 209-222. Jaeger, F., Rudolph, N., Lang, F. & Schaumann, G.E. 2008. Effects of soil solution's constituents on proton NMR relaxometry of soil samples. Soil Science Society of Am

Schaumann, G. E.; Jaeger, F.; Bayer, J. V.

2009-04-01

159

Soil invertebrates as bioindicators of urban soil quality  

International Nuclear Information System (INIS)

This study aimed at relating the abundance and diversity of invertebrate communities of urban soils to chemical and physical soil characteristics and to identify the taxa most sensitive or tolerant to soil stressors. The invertebrate community of five urban soils in Naples, Italy, was sampled. To assess soil quality invertebrate community indices (Shannon, Simpson, Menhinick and Pielou indices), Acarina/Collembola ratios, and the soil biological quality index (QBS) were calculated. The chemical and physical characteristics of the soils strongly differed. Abundance rather than taxa richness of invertebrates were more affected by soil characteristics. The community was more abundant and diverse in the soils with high organic matter and water content and low metal (Cu, Pb, Zn) concentrations. The taxa more resistant to the urban environment included Acarina, Enchytraeids, Collembola and Nematoda. Collembolans appeared particularly sensitive to changing soil properties. Among the investigated indices, QBS seems most appropriate for soil quality assessment. - Highlights: ? The abundance and diversity of invertebrate communities was related to properties and metal contents of urban soils. ? Several (biodiversity) indices were calculated and compared to evaluate soil quality. ? Metal contamination affected invertebrate density and diversity. ? The taxa more tolerant to metal contamination were Acarina, Enchytraeids, Collembola and Nematoda. ? The soil biological qumatoda. ? The soil biological quality index QBS index was most appropriate for soil quality assessment. - Soil metal contamination negatively affected soil invertebrate abundance and diversity.

160

Determining a Soil's Textural Classification  

Science.gov (United States)

In this activity students use screen sieves to determine the percent of sand, silt, and clay in a soil sample. They then use a tertiary soil diagram to determine the generic soil name of their sample. Students will learn to use particle size analysis as a tool to determine a soil's texture and understand the role of sand, silt, and clay sized particles in a soil. The site has a link to obtain the required soil diagram.

161

Soil nematode communities in grasslands  

OpenAIRE

This thesis summarizes the results of five studies investigating the effect of plant species on soil nematode communities in grasslands. Nematodes (roundworms) are ubiquitous members of the soil fauna and have been much used as indicators of soil conditions. Plants have the ability to affect soil organisms through structural modification of the soil habitat and through the quantity and quality of organic matter that is returned to soil, in the form of plant litter and root exudates. The influ...

Viketoft, Maria

2007-01-01

162

A computer model for predicting two-phase ground water transport in the soil surrounding a growing melt in the in situ vitrification process  

Energy Technology Data Exchange (ETDEWEB)

Two different computer models are tested for their usefulness in predicting the water balance and pressure field surrounding a growing hemispherical In Situ Vitrification (ISV) melt. The melt is centered under the flat surface of a hemisphere of soil contained by an impervious wall. The control volume method is employed for balancing heat, and mass in each model. The soil is considered a porous media; consequently, fluid velocity can be modeled by Darcy`s equation. Both computer models employ grids which adapt to the transient boundary of the growing melt. Computational Grid I (CGI) adapts with the melt boundary by contracting in the radial direction only. In addition to adapting to the melt boundary, Computational Grid II (CGII) also adapts to the liquid-vapor interface which moves outward from the 1,700 C melt in response to the formation of Vapor. CGII has been devised in order to attempt to reduce, at a reasonable CPU cost, the numerical pressure oscillation which arises when the grid is too coarse. A very fine CGI is used as a benchmark to test CGII and a coarser version of CGI. Results from the two CGI and the one CGII cases are presented graphically to illustrate the mass flux of liquid and vapor water and the build-up in pressure as the melt boundary approaches the impermeable wall.

Schreiber, W. [Univ. of Alabama, Tuscaloosa, AL (United States). Dept. of Mechanical Engineering

1996-12-31

163

A computer model for predicting two-phase ground water transport in the soil surrounding a growing melt in the in situ vitrification process  

International Nuclear Information System (INIS)

Two different computer models are tested for their usefulness in predicting the water balance and pressure field surrounding a growing hemispherical In Situ Vitrification (ISV) melt. The melt is centered under the flat surface of a hemisphere of soil contained by an impervious wall. The control volume method is employed for balancing heat, and mass in each model. The soil is considered a porous media; consequently, fluid velocity can be modeled by Darcy's equation. Both computer models employ grids which adapt to the transient boundary of the growing melt. Computational Grid I (CGI) adapts with the melt boundary by contracting in the radial direction only. In addition to adapting to the melt boundary, Computational Grid II (CGII) also adapts to the liquid-vapor interface which moves outward from the 1,700 C melt in response to the formation of Vapor. CGII has been devised in order to attempt to reduce, at a reasonable CPU cost, the numerical pressure oscillation which arises when the grid is too coarse. A very fine CGI is used as a benchmark to test CGII and a coarser version of CGI. Results from the two CGI and the one CGII cases are presented graphically to illustrate the mass flux of liquid and vapor water and the build-up in pressure as the melt boundary approaches the impermeable wall

164

Soil and vegetation surveillance  

Energy Technology Data Exchange (ETDEWEB)

Soil sampling and analysis evaluates long-term contamination trends and monitors environmental radionuclide inventories. This section of the 1994 Hanford Site Environmental Report summarizes the soil and vegetation surveillance programs which were conducted during 1994. Vegetation surveillance is conducted offsite to monitor atmospheric deposition of radioactive materials in areas not under cultivation and onsite at locations adjacent to potential sources of radioactivity.

Antonio, E.J.

1995-06-01

165

Campus Field Soil Geomorphology  

Science.gov (United States)

In this activity, students have an opportunity to learn about the geomorphology and soils of your campus. Within a team, students collect soils information and use it to construct of stratigraphic cross-section and outline major geologic events in the history of a given site.

Dolliver, Holly

166

Creative Soil Conservation  

Science.gov (United States)

Take plant lessons outdoors with this engaging and inquiry-based activity in which third-grade students learn how to apply soil conservation methods to growing plants. They also collect data and draw conclusions about the effectiveness of their method of soil conservation. An added benefit to this activity is that the third-grade students played

Smith, Martha

2010-01-01

167

The Soil Series in Soil Classifications of the United States  

Science.gov (United States)

Organized national soil survey began in the United States in 1899, with soil types as the units being mapped. The soil series concept was introduced into the U.S. soil survey in 1903 as a way to relate soils being mapped in one area to the soils of other areas. The original concept of a soil series was all soil types formed in the same parent materials that were of the same geologic age. However, within about 15 years soil series became the primary units being mapped in U.S. soil survey. Soil types became subdivisions of soil series, with the subdivisions based on changes in texture. As the soil series became the primary mapping unit the concept of what a soil series was also changed. Instead of being based on parent materials and geologic age, the soil series of the 1920s was based on the morphology and composition of the soil profile. Another major change in the concept of soil series occurred when U.S. Soil Taxonomy was released in 1975. Under Soil Taxonomy, the soil series subdivisions were based on the uses the soils might be put to, particularly their agricultural uses (Simonson, 1997). While the concept of the soil series has changed over the years, the term soil series has been the longest-lived term in U.S. soil classification. It has appeared in every official classification system used by the U.S. soil survey (Brevik and Hartemink, 2013). The first classification system was put together by Milton Whitney in 1909 and had soil series at its second lowest level, with soil type at the lowest level. The second classification system used by the U.S. soil survey was developed by C.F. Marbut, H.H. Bennett, J.E. Lapham, and M.H. Lapham in 1913. It had soil series at the second highest level, with soil classes and soil types at more detailed levels. This was followed by another system in 1938 developed by M. Baldwin, C.E. Kellogg, and J. Thorp. In this system soil series were again at the second lowest level with soil types at the lowest level. The soil type concept was dropped and replaced by the soil phase in the 1950s in a modification of the 1938 Baldwin et al. classification (Simonson, 1997). When Soil Taxonomy was released in 1975, soil series became the most detailed (lowest) level of the classification system, and the only term maintained throughout all U.S. classifications to date. While the number of recognized soil series have increased steadily throughout the history of U.S. soil survey, there was a rapid increase in the recognition of new soil series following the introduction of Soil Taxonomy (Brevik and Hartemink, 2013). References Brevik, E.C., and A.E. Hartemink. 2013. Soil maps of the United States of America. Soil Science Society of America Journal 77:1117-1132. doi:10.2136/sssaj2012.0390. Simonson, R.W. 1997. Evolution of soil series and type concepts in the United States. Advances in Geoecology 29:79-108.

Indorante, Samuel; Beaudette, Dylan; Brevik, Eric C.

2014-05-01

168

Characterization of Dispersive Soils  

Directory of Open Access Journals (Sweden)

Full Text Available Dispersive soils which occur in many parts of the world are easily erodible and segregate in water pose serious problems of stability of earth and earth retaining structures. The mechanism of dispersivity of soils is reasonably well understood. However there is simple method to identify the dispersivity of the soils and even more difficult to quantify the dispersivity. Visual classification, Atterbergs limits and particle size analysis do not provide sufficient basis to differentiate between dispersive clays and ordinary erosion resistant clays. Pinhole test and double hydrometer test are the only two tests that are in vogue to identify the dispersive soils. This paper explores the possibility of using other standard tests such as shrinkage limit and unconfined compressive strength tests to quantify the dispersivity of the soils. The rationale of using the methods and correlation between the dispersivity determined by various methods has been explained. It has been concluded that dispersivity ascertained from strength tests is more reliable.

S. V. Dinesh

2011-06-01

169

Soil Classification Using GATREE  

Directory of Open Access Journals (Sweden)

Full Text Available This paper details the application of a genetic programming framework forclassification of decision tree of Soil data to classify soil texture. The database containsmeasurements of soil profile data. We have applied GATree for generating classificationdecision tree. GATree is a decision tree builder that is based on Genetic Algorithms(GAs. The idea behind it is rather simple but powerful. Instead of using statistic metricsthat are biased towards specific trees we use a more flexible, global metric of tree qualitythat try to optimize accuracy and size. GATree offers some unique features not to befound in any other tree inducers while at the same time it can produce better results formany difficult problems. Experimental results are presented which illustrate theperformance of generating best decision tree for classifying soil texture for soil data set.

P.Bhargavi

2010-10-01

170

Soil Classification Using GATree  

CERN Document Server

This paper details the application of a genetic programming framework for classification of decision tree of Soil data to classify soil texture. The database contains measurements of soil profile data. We have applied GATree for generating classification decision tree. GATree is a decision tree builder that is based on Genetic Algorithms (GAs). The idea behind it is rather simple but powerful. Instead of using statistic metrics that are biased towards specific trees we use a more flexible, global metric of tree quality that try to optimize accuracy and size. GATree offers some unique features not to be found in any other tree inducers while at the same time it can produce better results for many difficult problems. Experimental results are presented which illustrate the performance of generating best decision tree for classifying soil texture for soil data set.

Bhargavi, P

2010-01-01

171

Soil bacteria for remediation of polluted soils  

Energy Technology Data Exchange (ETDEWEB)

Soil bacteria, specifically adapted to contaminated soils, may be used for the remediation of polluted soils. The Flemish research institute VITO has established a collection of bacteria, which were isolated from contaminated areas. This collection includes microbacteria degrading mineral oils (Pseudomonas sp., Acinetobacter sp. and others), microbacteria degrading polycyclic aromatic hydrocarbons (genera Sphingomonas and Mycobacterium), microbacteria degrading polychlorobiphenyls (genus Ralstonia and strains related to beta-Proteobacteria), and metal resistant bacteria with plasmid borne resistances to Cd, Zn, Ni, Co, Cu, Hg, and Cr. Bench-scale reactors were developed to investigate the industrial feasibility of bioremediation. Batch Stirred Tank Reactors were used to evaluate the efficiency of oil degraders. Soils, contaminated with non-ferrous metals, were treated using a Bacterial Metal Slurry Reactor. It was found that the reduction of the Cd concentration may vary strongly from sample to sample: reduction factors vary from 95 to 50%. Is was shown that Cd contained in metallic sinter and biologically unavailable Cd could not be removed.

Springael, D.; Bastiaens, L.; Carpels, M.; Mergaey, M.; Diels, L.

1996-09-18

172

Soil survey, soil databases and soil monitoring in Spain  

OpenAIRE

Meetings of European Union Heads of Soil Survey Organisations were held in 1989 and 1994 respectively. Both were followed by publication of monographs describing the state-of-the-art in each of the member countries (Hodgson 1991; Le Bas & Jamagne 1996). Limited progress has been made in Spain since then, except for a proposal for an ambitious macroproject (PNCTA), the prospects for which now seem somewhat uncertain. Readers interested in historical aspects of Spanis...

Iba?n?ez Marti?n, Juan Jose?; Sa?nchez Di?az, Juan; La Rosa, Diego; Alba, S.

1999-01-01

173

Introductory Soil Science Exercises Using USDA Web Soil Survey  

Science.gov (United States)

The USDA, Natural Resource Conservation Service (NRCS) Web Soil Survey is a valuable teaching tool for soil science education. By incorporating the Web Soil Survey into an undergraduate-level course, students are able to use the most detailed digital soil survey information without the steep learning curve associated with geographic information

Post, Christopher J.; Mikhailova, Elena; McWhorter, Christopher M.

2007-01-01

174

Describing Soils: Calibration Tool for Teaching Soil Rupture Resistance  

Science.gov (United States)

Rupture resistance is a measure of the strength of a soil to withstand an applied stress or resist deformation. In soil survey, during routine soil descriptions, rupture resistance is described for each horizon or layer in the soil profile. The lower portion of the rupture resistance classes are assigned based on rupture between thumb and

Seybold, C. A.; Harms, D. S.; Grossman, R. B.

2009-01-01

175

Iodine in soil  

International Nuclear Information System (INIS)

A literature study of the migration and the appearance of iodine isotopes in the bio-sphere particularly in soil is presented. Some important papers in the field of iodine appearance in soil and the appearance of 129I in the surroundings of reprocessing plants are discussed. The most important conclusions are: 1. Iodine binds to organic matter in the soil and also to some oxides of aluminium and iron. 2. If the iodine is not bound to the soil a large fraction of added 129I is volatilized after a rather short period. 3. The binding and also the volatilisation seems to be due to biological activity in the soil. It may take place within living microorganisms or by external enzymes excreted from microorganisms. 4. Due to variations in the composition of soil there may be a large variation in the distribution of 129I in the vertical profile of soil - usually most of the 129I in the upper layer - which also results in large variations in the 129I uptake to plants

176

Soil washing treatability study  

International Nuclear Information System (INIS)

Soil washing was identified as a viable treatment process option for remediating soil at the FEMP Environmental Management Project (FEMP). Little information relative to the specific application and potential effectiveness of the soil washing process exists that applies to the types of soil at the FEMP. To properly evaluate this process option in conjunction with the ongoing FEMP Remedial Investigation/Feasibility Study (RI/FS), a treatability testing program was necessary to provide a foundation for a detailed technical evaluation of the viability of the process. In August 1991, efforts were initiated to develop a work plan and experimental design for investigating the effectiveness of soil washing on FEMP soil. In August 1992, the final Treatability Study Work Plan for Operable Unit 5: Soil Washing (DOE 1992) was issued. This document shall be referenced throughout the remainder of this report as the Treatability Study Work Plan (TSWP). The purpose of this treatability study was to generate data to support initial screening and the detailed analysis of alternatives for the Operable Unit 5 FS

177

Climate Strategic Soil Management  

Directory of Open Access Journals (Sweden)

Full Text Available The complex and strong link between soil degradation, climate change and food insecurity is a global challenge. Sustainable agricultural systems must be integral to any agenda to address climate change and variability, improve renewable fresh water supply and quality, restore degraded soils and ecosystems and advance food security. These challenges are being exacerbated by increasing population and decreasing per capita arable land area and renewable fresh water supply, the increasing frequency of extreme events, the decreasing resilience of agroecosystems, an increasing income and affluent lifestyle with growing preference towards meat-based diet and a decreasing soil quality and use efficiency of inputs. Reversing these downward spirals implies the implementation of proven technologies, such as conservation agriculture, integrated nutrient management, precision agriculture, agroforestry systems, etc. Restoration of degraded soil and desertified ecosystems and the creation of positive soil and ecosystem C budgets are important. Urban agriculture and green roofs can reduce the energy footprint of production chains for urban and non-urban areas and enhance the recycling of by-products. Researchable priorities include sustainable land use and soil/water management options, judicious soil governance and modus operandi towards payments to land managers for the provisioning of ecosystem services.

Rattan Lal

2014-02-01

178

Soil washing treatability study  

Energy Technology Data Exchange (ETDEWEB)

Soil washing was identified as a viable treatment process option for remediating soil at the FEMP Environmental Management Project (FEMP). Little information relative to the specific application and potential effectiveness of the soil washing process exists that applies to the types of soil at the FEMP. To properly evaluate this process option in conjunction with the ongoing FEMP Remedial Investigation/Feasibility Study (RI/FS), a treatability testing program was necessary to provide a foundation for a detailed technical evaluation of the viability of the process. In August 1991, efforts were initiated to develop a work plan and experimental design for investigating the effectiveness of soil washing on FEMP soil. In August 1992, the final Treatability Study Work Plan for Operable Unit 5: Soil Washing (DOE 1992) was issued. This document shall be referenced throughout the remainder of this report as the Treatability Study Work Plan (TSWP). The purpose of this treatability study was to generate data to support initial screening and the detailed analysis of alternatives for the Operable Unit 5 FS.

Krstich, M.

1995-12-01

179

SOIL Geo-Wiki: A tool for improving soil information  

Science.gov (United States)

Crowdsourcing is increasingly being used as a way of collecting data for scientific research, e.g. species identification, classification of galaxies and unravelling of protein structures. The WorldSoilProfiles.org database at ISRIC is a global collection of soil profiles, which have been 'crowdsourced' from experts. This system, however, requires contributors to have a priori knowledge about soils. Yet many soil parameters can be observed in the field without specific knowledge or equipment such as stone content, soil depth or color. By crowdsourcing this information over thousands of locations, the uncertainty in current soil datasets could be radically reduced, particularly in areas currently without information or where multiple interpretations are possible from different existing soil maps. Improved information on soils could benefit many research fields and applications. Better soil data could enhance assessments of soil ecosystem services (e.g. soil carbon storage) and facilitate improved process-based ecosystem modeling from local to global scales. Geo-Wiki is a crowdsourcing tool that was developed at IIASA for land cover validation using satellite imagery. Several branches are now available focused on specific aspects of land cover validation, e.g. validating cropland extent or urbanized areas. Geo-Wiki Pictures is a smart phone application for collecting land cover related information on the ground. The extension of Geo-Wiki to a mobile environment provides a tool for experts in land cover validation but is also a way of reaching the general public in the validation of land cover. Here we propose a Soil Geo-Wiki tool that builds on the existing functionality of the Geo-Wiki application, which will be largely designed for the collection and sharing of soil information. Two distinct applications are envisaged: an expert-oriented application mainly for scientific purposes, which will use soil science related language (e.g. WRB or any other global reference soil classification system) and allow experts to upload and share scientifically rigorous soil data; and an application oriented towards the general public, which will be more focused on describing well observed, individual soil properties using simplified classification keys. The latter application will avoid the use of soil science related terminology and focus on the most useful soil parameters such as soil surface features, stone content, soil texture, soil plasticity, calcium carbonate presence, soil color, soil pH, soil repellency, and soil depth. Collection of soil and landscape pictures will also be supported in Soil Geo-Wiki to allow for comprehensive data collection while simultaneously allowing for quality checking by experts.

Skalsk, Rastislav; Balkovic, Juraj; Fritz, Steffen; See, Linda; van der Velde, Marijn; Obersteiner, Michael

2014-05-01

180

Parameterization of radiocaesium soil-plant transfer using soil characteristics  

International Nuclear Information System (INIS)

A model of radionuclide soil-plant transfer is proposed to parameterize the transfer factor by soil and soil solution characteristics. The model is tested with experimental data on the aggregated transfer factor Tag and soil parameters for 8 forest sites in Baden-Wuerttemberg. It is shown that the integral soil-plant transfer factor can be parameterized through radiocaesium exchangeability, capacity of selective sorption sites and ion composition of the soil solution or the water extract. A modified technique of (FES) measurement for soils with interlayer collapse is proposed. (author)

181

Soil chromatographic movement of technetium-99 through selected Minnesota soils  

International Nuclear Information System (INIS)

We monitored the movement of technetium-99 through 41 samples of Minnesota soils, using soil column layer chromatography (CLC), a modification of soil thin layer chromatography. Under the aerobic conditions of soil CLC, 99Tc occurs as the pertechnetate anion. Pertechnetate movement in the soils was characterized by the traditional R/sub f/ chromatographic parameter. Reduced R/sub f/ values were statistically related to elevated levels of soil organic matter. Complexation of 99Tc, related to soil organic matter, was weak. Elution patterns of 99Tc in the soil CLC columns were asymmetric, with pertechnetate retardation associated with both hydrodynamic dispersion and weak retention. Pertechnetate was less mobile than was Cl- in selected soils by soil CLC

182

Remediating munitions contaminated soils  

Energy Technology Data Exchange (ETDEWEB)

The former Nebraska Ordnance Plant (NOP) at Mead, NE was a military loading, assembling, and packing facility that produced bombs, boosters and shells during World War II and the Korean War (1942-1945, 1950-1956). Ordnances were loaded with 2,4,6-trinitrotoluene (TNT), amatol (TNT and NH{sub 4}NO{sub 3}), tritonal (TNT and Al) and Composition B (hexahydro-1,3,5-trinitro-1,3,5-triazine [RDX] and TNT). Process waste waters were discharged into wash pits and drainage ditches. Soils within and surrounding these areas are contaminated with TNT, RDX and related compounds. A continuous core to 300 cm depth obtained from an NOP drainage ditch revealed high concentrations of TNT in the soil profile and substantial amounts of monoamino reduction products, 4-amino-2,6-dinitrotoluene (4ADNT) and 2-amino-4,6-dinitrotoluene (2ADNT). Surface soil contained TNT in excess of 5000 mg kg{sup -1} and is believed to contain solid phase TNT. This is supported by measuring soil solution concentrations at various soil to solution ratios (1:2 to 1:9) and obtaining similar TNT concentrations (43 and 80 mg L{sup -1}). Remediating munitions-contaminated soil at the NOP and elsewhere is of vital interest since many of the contaminants are carcinogenic, mutagenic or otherwise toxic to humans and the environment. Incineration, the most demonstrated remediation technology for munitions-containing soils, is costly and often unacceptable to the public. Chemical and biological remediation offer potentially cost-effective and more environmentally acceptable alternatives. Our research objectives are to: (a) characterize the processes affecting the transport and fate of munitions in highly contaminated soil; (b) identify effective chemical and biological treatments to degrade and detoxify residues; and (c) integrate these approaches for effective and practical remediation of soil contaminated with TNT, RDX, and other munitions residues.

Shea, P.J.; Comfort, S.D. [Univ. of Nebraska, Lincoln, NE (United States)

1995-10-01

183

Development of soil taxation and soil classification as furthered by the Austrian Soil Science Society  

Science.gov (United States)

Soil taxation and soil classification are important drivers of soil science in Austria. However, the tasks are quite different: whereas soil taxation aims at the evaluation of the productivity potential of the soil, soil classification focusses on the natural development and - especially nowadays - on functionality of the soil. Since the foundation of the Austrian Soil Science Society (ASSS), representatives both directions of the description of the soil have been involved in the common actions of the society. In the first years it was a main target to improve and standardize field descriptions of the soil. Although both systems differ in the general layout, the experts should comply with identical approaches. According to this work, a lot of effort has been put into the standardization of the soil classification system, thus ensuring a common basis. The development, state of the art and further development of both classification and taxation systems initiated and carried out by the ASSS will be shown.

Baumgarten, Andreas

2013-04-01

184

Soil temperature and soil moisture induced spatio-temporal variability of soil respiration in winter wheat  

Science.gov (United States)

Soil respiration is the major transfer of CO2 from the soil to the atmosphere and is characterized by a high spatio-temporal variability depending, among others, on variations in soil temperature and soil moisture. We simultaneously measured soil respiration, soil temperature (3 cm depth) and soil moisture (0-5 cm depth) in winter wheat from April to September 2008 at a 50x50 m plot at a site near Jlich, Germany. The average soil respiration rate over the whole sampling period was 3.8 1.5 mol m-2 s-1. Spatial variations of soil respiration, represented by the coefficient of variation (CV), were in average more than 5 times higher than the spatial variations of soil temperature and soil moisture, respectively. Concerning soil respiration, considerably higher spatial variations were observed during the growth period of winter wheat. Semivariogram analysis revealed a strong spatial autocorrelation of soil temperature, whereas a moderate spatial autocorrelation of soil respiration and soil moisture was detected. However, the range of spatial autocorrelation was nearly similar for all three variables, on average 20 m. For the given temporal and spatial scale, a large proportion in temporal changing of the spatial structure of soil respiration could be explained by the spatial distribution of soil moisture.

Prolingheuer, N.; Herbst, M.; Graf, A.; Vanderborght, J.; Vereecken, H.

2009-04-01

185

Soil fauna and soil functions: a jigsaw puzzle  

OpenAIRE

Terrestrial ecologists and soil modelers have traditionally portrayed the inhabitants of soil as a black box labeled as "soil fauna" or "decomposers or detritivores assuming that they just merely recycle the deposited dead plant material. Soil is one of the most diverse habitats on Earth and contains one of the most diverse assemblages of living organisms; however, the opacity of this world has severely limited our understanding of their functional contributions to soil processes and to ec...

Briones, Mariaj I.

2014-01-01

186

SCALING METHODS IN SOIL PHYSICS  

Science.gov (United States)

Soil physical properties are needed to understand and manage natural systems spanning an extremely wide range of scales. Much of soil data are obtained from small soil samples and cores, monoliths, or small field plots, yet the goal is to reconstruct soil physical properties across fields, watershed...

187

HOW SOIL FORMING PROCESSES DETERMINE SOIL-BASED VITICULTURAL ZONING  

Directory of Open Access Journals (Sweden)

Full Text Available The aim of this study was to elucidate the soil forming processes of representative vineyard soils, and to discuss the implications on a soil-based viticultural zoning at very detailed scale. The study area is located in Priorat, Penedes and Conca de Barbera viticultural areas (Catalonia, North-eastern Spain. The studied soils belong to representative soil map units determined at 1:5,000 scale, according to Soil Taxonomy classification. The soil forming processes, identified through morphological and micromorphological analyses, have significant effects on some soil properties. For example, the different processes of clay accumulation in soils developed from granodiorites in Priorat or gravel deposits in Conca de Barbera, are primarily responsible for significant differences in clay content, available water capacity and cation exchange capacity. These soils properties, especially those related to soil moisture regime, have a direct influence on vineyard management and grape quality. However, soil forming processes are not always reflected on soil classification, especially in soils modified by man. We show that climate or geology alone cannot be used in viticultural zoning at very detailed scale, unless soil forming processes are taken into account.

J.M Ubalde

2011-01-01

188

HOW SOIL FORMING PROCESSES DETERMINE SOIL-BASED VITICULTURAL ZONING  

Scientific Electronic Library Online (English)

Full Text Available SciELO Chile | Language: English Abstract in english The aim of this study was to elucidate the soil forming processes of representative vineyard soils, and to discuss the implications on a soil-based viticultural zoning at very detailed scale. The study area is located in Priorat, Penedes and Conca de Barbera viticultural areas (Catalonia, North-east [...] ern Spain). The studied soils belong to representative soil map units determined at 1:5,000 scale, according to Soil Taxonomy classification. The soil forming processes, identified through morphological and micromorphological analyses, have significant effects on some soil properties. For example, the different processes of clay accumulation in soils developed from granodiorites in Priorat or gravel deposits in Conca de Barbera, are primarily responsible for significant differences in clay content, available water capacity and cation exchange capacity. These soils properties, especially those related to soil moisture regime, have a direct influence on vineyard management and grape quality. However, soil forming processes are not always reflected on soil classification, especially in soils modified by man. We show that climate or geology alone cannot be used in viticultural zoning at very detailed scale, unless soil forming processes are taken into account.

J.M, Ubalde; X, Sort; R.M, Poch.

189

Soil and soil environmental quality monitoring in China: a review.  

Science.gov (United States)

Over the past few decades, numerous concerns have been raised in China over the issue of environmental sustainability. Various soil survey and monitoring programs have been carried out in China to study soil quality, and to provide a scientific basis for environment policy making. This paper provides an overview of past and current soil quality surveys and monitoring activities in China. This paper includes a summary of concerns over background concentrations of elements in soil, and soil environmental standards and guidelines in China. Levels of pollution in urban soil, agricultural soil, and soil in mining and smelting areas were compared using the concentrations and pollution indexes. In addition to soil surveys, soil monitoring is essential to study the data and to examine the effects of contaminants in soils. However, the current soil quality monitoring system was insufficient to accurately determine the soil quality status of soils across China. For accurate soil monitoring in China, it will be necessary to set up routine monitoring systems at various scales (national, provincial, and local scales), taking into consideration monitoring indicators and quality assurance. This is currently an important priority for the environmental protection administration of China. PMID:24875802

Teng, Yanguo; Wu, Jin; Lu, Sijin; Wang, Yeyao; Jiao, Xudong; Song, Liuting

2014-08-01

190

Attenuation coefficients of soils  

International Nuclear Information System (INIS)

As a prerequisite to the interpretation of gamma-spectrometric in situ measurements of activity concentrations of soil radionuclides the attenuation of 60 to 1332 keV gamma radiation by soil samples varying in water content and density has been investigated. A useful empirical equation could be set up to describe the dependence of the mass attenuation coefficient upon photon energy for soil with a mean water content of 10%, with the results comparing well with data in the literature. The mean density of soil in the GDR was estimated at 1.6 g/cm3. This value was used to derive the linear attenuation coefficients, their range of variation being 10%. 7 figs., 5 tabs. (author)

191

Airborne soil concentrations  

International Nuclear Information System (INIS)

Airborne soil concentrations downwind of an isolated field were measured during one dust storm. Concentration increased as the friction velocity increased, but the increase was a function of particle diameter

192

Soil degradation in Pakistan  

International Nuclear Information System (INIS)

This paper diagnoses the issues involved behind the current state, usage, interactions and linkages in the soils in Pakistan. The condition of soils is deteriorating due to developmental and environmental factors such as soil degradation, water pollution, fauna degeneration etc. Issues, problems and constraints faced in the management and usage of soils are diagnosed at different levels in the ecosystems predominant in Pakistan. The research questions propose effective solutions, types of instruments, methods or processes to resolve the issues within the various areas or ecosystems in the most sustainable and effective manner [23]. Biological solutions and methods can be applied at the sub-system level by private individuals or communities at a lower cost, and at a more localized level than engineering methods. Engineering methods may be suited for interventions at a system level rather than at a sub-system level; but even at this level they will be complementary with biological methods. (author)

193

European Atlas of Soil Biodiversity  

DEFF Research Database (Denmark)

Soil is one of the fundamental components for supporting life on Earth. Most ecosystem processes and global functions that occur within soil are driven by living organisms that, in turn, sustain life above ground. However, despite the fact that soils are home to a quarter of all living species on Earth, life within the soil is often hidden away and suffers by being 'out of sight and out of mind'. What kind of life is there in soil? What do we mean by soil biodiversity? What is special about soil biology? How do our activities affect soil ecosystems? What are the links between soil biota and climate change? The first ever European Atlas of Soil Biodiversity uses informative texts, stunning photographs and maps to answer these questions and other issues. The European Atlas of Soil Biodiversity functions as a comprehensive guide allowing non-specialists to access information about this unseen world. The first part of the book provides an overview of the below ground environment, soil biota in general, the ecosystem functions that soil organism perform, the important value it has for human activities and relevance for global biogeochemical cycles. The second part is an 'Encyclopedia of Soil Biodiversity'. Starting with the smallest organisms such as the bacteria, this segment works through a range of taxonomic groups such as fungi, nematodes, insects and macro-fauna to illustrate the astonishing levels of heterogeneity of life in soil. The European Atlas of Soil Biodiversity is more than just a normal atlas. Produced by leading soil scientists from Europe and other parts of the world under the auspice of the International Year of Biodiversity 2010, this unique document presents an interpretation of an often neglected biome that surrounds and affects us all. The European Atlas of Soil Biodiversity is an essential reference to the many and varied aspects of soil. The overall goal of this work is to convey the fundamental necessity to safeguard soil biodiversity in order to guarantee life on this planet.

2010-01-01

194

Degradation and resilience of soils  

OpenAIRE

Debate on global soil degradation, its extent and agronomic impact, can only be resolved through understanding of the processes and factors leading to establishment of the cause-effect relationships for major soils, ecoregions, and land uses. Systematic evaluation through long-term experimentation is needed for establishing quantitative criteria of (i) soil quality in relation to specific functions; (ii) soil degradation in relation to critical limits of key soil properties and processes; and...

Lal, R.

1997-01-01

195

Collapsible soils an overview  

OpenAIRE

Collapse potential in unsaturated soil was first identified and quantified by researchers in South Africa. A landmark paper was published by Ken Schwartz in 1985 presenting the state of the art at that time. Since then, international researchers have expanded on the understanding of what collapsible soils might entail. These include saturated silts and sensitive clays. This article highlights some of the new developments and presents a theoretical yield model in an attempt to improve th...

Rust, Eben; Heymann, Gerhard; Jones, Gary

2010-01-01

196

Climate Strategic Soil Management  

OpenAIRE

The complex and strong link between soil degradation, climate change and food insecurity is a global challenge. Sustainable agricultural systems must be integral to any agenda to address climate change and variability, improve renewable fresh water supply and quality, restore degraded soils and ecosystems and advance food security. These challenges are being exacerbated by increasing population and decreasing per capita arable land area and renewable fresh water supply, the increasing freque...

Rattan Lal

2014-01-01

197

Active synthetic soil  

Science.gov (United States)

A synthetic soil/fertilizer for horticultural application having all the agronutrients essential for plant growth is disclosed. The soil comprises a synthetic apatite fertilizer having sulfur, magnesium and micronutrients dispersed in a calcium phosphate matrix, a zeolite cation exchange medium saturated with a charge of potassium and nitrogen cations, and an optional pH buffer. Moisture dissolves the apatite and mobilizes the nutrient elements from the apatite matrix and the zeolite charge sites.

Ming, Douglas W. (Inventor); Henninger, Donald L. (Inventor); Allen, Earl R. (Inventor); Golden, Dadigamuwage C. (Inventor)

1995-01-01

198

Classification of Organic Soils  

OpenAIRE

The presence of organics in soils is generally associated with high compressibility, significant secondary compression, often unsatisfactory strength characteristics, and low unit weight. As a result of the above, many state DOTs (Departments of Transportation) in the United States have strict limits on the maximum value of the organic content (2-7%) that can be present in soils to be used as sub grades and backfills. The loss on ignition test is the most widely used technique for measuring o...

Huang, Pao-tsung; Patel, Mital; Santagata, Maria Caterina; Bobet, Antonio

2009-01-01

199

Earthworms and Soil Pollutants  

OpenAIRE

Although the toxicity of metal contaminated soils has been assessed with various bioassays, more information is needed about the biochemical responses, which may help to elucidate the mechanisms involved in metal toxicity. We previously reported that the earthworm, Eisenia fetida, accumulates cadmium in its seminal vesicles. The bio-accumulative ability of earthworms is well known, and thus the earthworm could be a useful living organism for the bio-monitoring of soil pollution. In this short...

Kazuyoshi Tamae; Takeshi Hirano

2011-01-01

200

SOIL MOISTURE EFFECTS ON ENERGY REQUIREMENTS AND SOIL DISRUPTION OF SUBSOILING A COASTAL PLAIN SOIL  

Science.gov (United States)

An experiment was conducted to determine the optimum moisture content to subsoil based on tillage forces and soil disruption. Two different shanks, a straight shank and a "minimum- tillage" shank, were tested in a Coastal Plain soil in the soil bins of the National Soil Dynamics Laboratory in Aubur...

201

Evaluating Soil Contamination  

Science.gov (United States)

This compilation was designed to help U.S. Fish and Wildlife Service contaminant specialists evaluate the degree of contamination of a soil, based on chemical analyses. Included are regulatory criteria, opinions, brief descriptions of scientific articles, and miscellaneous information that might be useful in making risk assessments. The intent was to make hard-to-obtain material readily available to contaminant specialists, but not to critique the material or develop new criteria. The compilation is to be used with its index, which includes about 200 contaminants. There are several entries for a few of the most thoroughly studied contaminants, but for most of them the information available is meager. Entries include soil contaminant criteria from other countries, contaminant guidelines for applying sewage sludge to soil, guidelines for evaluating sediments, background soil concentrations for various elements, citations to scientific articles that may help estimate the potential movement of soil contaminants into wildlife food chains, and a few odds and ends. Articles on earthworms were emphasized because they are a natural bridge between soil and many species of wildlife.

Beyer, W.N.

1990-01-01

202

Soil physics and the water management of spatially variable soils  

International Nuclear Information System (INIS)

The physics of macroscopic soil-water behaviour in inert porous materials has been developed by considering water flow to take place in a continuum. This requires the flow region to consist of an assembly of representative elementary volumes, repeated throughout space and small compared with the scale of observations. Soil-water behaviour in swelling soils may also be considered as a continuum phenomenon so long as the soil is saturated and swells and shrinks in the normal range. Macroscale heterogeneity superimposed on the inherent microscale heterogeneity can take many forms and may pose difficulties in the definition and measurement of soil physical properties and also in the development and use of predictive theories of soil-water behaviour. Thus, measurement techniques appropriate for uniform soils are often inappropriate, and criteria for soil-water management, obtained from theoretical considerations of behaviour in equivalent uniform soils, are not applicable without modification when there is soil heterogeneity. The spatial variability of soil-water properties is shown in results from field experiments concerned with water flow measurements; these illustrate both stochastic and deterministic heterogeneity in soil-water properties. Problems of water management of spatially variable soils when there is stochastic heterogeneity appear to present an insuperable problem in the application of theory. However, for soils showing deterministic heterogeneity, soil-water theory has been used in the solution of soil-water management problems. Thus, scaling using similar media theory has been applied to the infiltration of water into soils that vary over a catchment area. Also, the drain spacing to control the water-table height in soils in which the hydraulic conductivity varies with depth has been calculated using groundwater seepage theory. (author)

203

Effects of environmental factors and soil properties on topographic variations of soil respiration  

Directory of Open Access Journals (Sweden)

Full Text Available Soil respiration rates were measured along different parts of a slope in (a an evergreen forest with mature soil and (b a deciduous forest with immature soil. The effects of soil temperature, soil moisture, and soil properties on soil respiration rates were estimated individually, and the magnitudes of these effects were compared between the deciduous and evergreen forests. In the evergreen forest with mature soil, soil properties had the greatest effect on soil respiration rates, followed by soil moisture and soil temperature. These results may be explained by different properties of soils that matured under different environments. Thus, we argue that the low soil respiration rates in Plot L of the evergreen forest resulted from soil properties and not from wet soil conditions. In the deciduous forest, soil respiration rates were more strongly affected by soil moisture and soil temperature than by soil properties, which were likely due to the immaturity of the forest soil.

K. Tamai

2009-11-01

204

GLOBE Videos: Soil Characterization - Soil Moisture (18:23 min)  

Science.gov (United States)

This video describes how to select a soil moisture study site and sampling strategy, and identifies what laboratory instruments will be needed to complete a soil moisture analysis. Students are shown collecting soil moisture data and asking questions about what soil moisture data might tell them about the environment. The resource includes a video and a written transcript, and is supported by the Soil Moisture Protocol in the GLOBE Teacher's Guide. This is one of five videos about soils in the 24-part instructional video series describing scientific protocols used by GLOBE (Global Learning and Observation to Benefit the Environment), a worldwide, hands-on, K-12 school-based science education program.

205

Diagenetic variation in the Oregon Coast Range: Implications for rock strength, soil production, hillslope form, and landscape evolution  

Science.gov (United States)

mechanisms by which lithology modulates geomorphic processes are poorly known. In the Oregon Coast Range (OCR), rhythmically bedded sandstones of the Eocene Tyee Formation underlie steep, soil-mantled hillslopes, with relatively uniform ridge-valley spacing. These characteristic landforms are perturbed where diagenetic variations manifest as resistant cliffs. Here we use petrology, rock mechanics, and lidar to characterize grain-scale variations in rock properties and their influence on rock strength, hillslope processes, and landscape morphology in two adjacent watersheds. Petrographic analyses suggest that a suite of diagenetic products in the "resistant" bedrock account for a 2.5 times increase in tensile strength relative to "typical" Tyee bedrock. Our reference catchment exhibits negligible resistant outcrops, and consistent hillslope gradients and longitudinal valley profiles. By contrast, the adjacent catchment teems with resistant, 1 to 10 m thick, noncontiguous sandstone beds that form hanging valleys with gentle upstream hillslopes and anomalously narrow valleys. Mechanical and topographic analyses suggest that the low fracture density characteristic of these resistant beds may render them relatively impervious to comminution by tree root activity, the dominant OCR soil production mechanism. Based on both hillslope gradient- and hilltop curvature-erosion models, we estimate that hillslopes perched above resistant beds erode at approximately half the pace of hillslopes unencumbered by downstream knickpoints. The diagenetic variations likely influence relief at the watershed scale. Depositional position and diagenetic processes appear to control the occurrence of resistant beds, providing a framework to quantify how seemingly subtle variations in rock properties can impose first-order controls on landscape form and evolution.

Marshall, Jill A.; Roering, Joshua J.

2014-06-01

206

Engineering Significant of Swelling Soils  

Directory of Open Access Journals (Sweden)

Full Text Available This study describes some of the most important swelling characters of expansive soils when used as foundation materials to support various types of civil engineering structures. Expansive soils are considered among difficult foundation materials and expand upon wetting and shrink upon losing moisture. They are considered problematic soils for architectural and civil engineers. These types of soils may cause minor to major structural damages to pavements as well as buildings. It is therefore essential to detect swelling soils from non-problematic foundation soils before any civil engineering projects are constructed over or adjacent to them. The study begins with definition of expansive soils and shows its distributions in the world as well as the basic causes for swelling potential that these type of soils poses. It is also shown that, the most probable depth of expansion to check for possible swelling potential for swelling soils is soils active zone. This zone is the most upper depth of expansive soil and it may extend up to 20 ft. (6 m below ground level. The moisture content of soil through active zone varies during different seasons while in lower part of expansive soil the moisture content stays constant during hot and cold season. Among various methods to check for swelling potential, plastic index and liquid limits are two most crucial factors, as these factors tend to increase, the swelling potential increase as well.

Behzad Kalantari

2012-08-01

207

Use of Landsat imagery to detect land cover changes for monitoring soil sealing; case study: Bologna province (Italy)  

Science.gov (United States)

Landsat archives (made accessible by USGS at no charge since 2011) have made available to the scientific community a large amount of satellite multispectral images, providing new opportunities for environmental information, such as the analysis of land use/cover changes, which represent important tools for planning and sustainable land management. Processing a time series images, the creation of land cover maps has been improved in order to analyze phenomena such as the soil sealing. The main topic of this work is in fact the detection of roads and buildings construction or everything that involve soil removing. This subject is highly relevant, given the impact of the phenomenon on land use planning, environmental sustainability, agricultural policies and urban runoff. The analysis, still in progress, has been applied to Bologna Province (Emilia-Romagna Region, Italy) that covers 3703 Km2. This area is strongly urbanized: 8,9% of the total surface is sealed against a national value of 6,7%, with the soil sealing rate which has been defined from recent studies as the fourth Italian value in the 2001/2011 period. Other information available for this territory derive from CORINE Land Cover and Copernicus Projects. In the first one, the minimum mapping unit is 25 ha and the one for change is 5 ha; these values are too large for an accurate detection of the soil sealing dynamics. On the other hand, the Copernicus Project provides an imperviousness layer with a better resolution (20x20 m2), but its maps start from 2006. Therefore, the potential of multispectral remote sensing analysis over large areas and the multitemporal Landsat availability have been combined for a better knowledge about land cover changes. For this work, Landsat 5 and Landsat 8 images have been acquired between 1987 and 2013, according to basic requirements as low cloud cover and a common acquisition season (summer). A supervised pixel-based classification has been performed, with maximum likelihood algorithm. Due to landscape heterogeneity, classification has been improved with auxiliary data, such as NDVI. Therefore, the obtained maps have been compared with a post-classification change detection procedure in order to quantify land use changes, with particular attention to the soil sealing increase.

Casciere, Rossella; Franci, Francesca; Bitelli, Gabriele

2014-08-01

208

Effects of Land Cover / Land Use, Soil Texture, and Vegetation on the Water Balance of Lake Chad Basin  

Science.gov (United States)

Lake Chad Basin (LCB) has experienced drastic changes of land cover and poor water management practices during the last 50 years. The successive droughts in the 1970s and 1980s resulted in the shortage of surface water and groundwater resources. This problem of drought has a devastating implication on the natural resources of the Basin with great consequence on food security, poverty reduction and quality of life of the inhabitants in the LCB. Therefore, understanding the effects of land use / land cover must be a first step to find how they disturb cycle especially the groundwater in the LCB. The abundance of groundwater is affected by the climate change through the interaction with surface water, such as lakes and rivers, and disuse recharge through an infiltration process. Quantifying the impact of climate change on the groundwater resource requires reliable forecasting of changes in the major climatic variables and other spatial variations including the land use/land cover, soil texture, topographic slope, and vegetation. In this study, we employed a spatially distributed water balance model WetSpass to simulate a long-term average change of groundwater recharge in the LCB of Africa. WetSpass is a water balance-based model to estimate seasonal and spatial distribution of surface runoff, interception, evapotranspiration, and groundwater recharge. The model is especially suitable for studying the effect of land use/land cover change on the water regime in the LCB. The present study describes the concept of the model and its application to the development of recharge map of the LCB. The study shows that major role in the water balance of LCB. The mean yearly actual evapotranspiration (ET) from the basin range from 60mm - 400 mm, which is 90 % (69mm - 430) of the annual precipitation from 2003 - 2010. It is striking that about 50 - 60 % of the total runoff is produced on build-up (impervious surfaces), while much smaller contributions are obtained from vegetated, bare soil and open water surfaces. The result of this study also shows that runoff is high in the clay, clay loam and sandy-clay loam due to the lack of infiltration process in clay soil from capping or crusting or sealing of the soil pores, therefore this situation will aid runoff. The application of the WetSpass model shows that precipitation, soil texture and land use / land cover are three controlling factors affecting the water balance in the LCB. Key words: Groundwater recharge, surface runoff, evapotranspiration, water balance, meteorological, draught, Landuse changes, climate changes, WetSpass, GIS.

Babamaaji, R. A.; Lee, J.

2013-12-01

209

Shrinking Behaviour of Badland Soil Under Different Soil Covers  

Directory of Open Access Journals (Sweden)

Full Text Available Indicators used to estimate the soil structure stability facing erosion are the basis of major indicators of soil quality, and their behaviour is affected by permanent soil properties, vegetation and management. The relation between the pore-volume fraction occupied by water and the pore size distribution in clay soils is studied by the shrinkage curve describing clay soil porosity dynamics as a function of soil moisture. The aim of this work is to study the shrinking behaviour of the surface soil in a badland site through the shrinkage curve and to assess its relations with vegetation. Six treatments with different soil vegetation cover and aspect were selected on a badland site in Pisticci (Southern Italy. Shrinkage curves were built from natural aggregates collected in the 0-10 cm soil depth. Soil stability under shaking in water was also determined, with pre-treatments in water, alcohol and benzene for the determination of the SSI (Soil Stability Index. Soil organic matter, electrical conductivity, ESP were determined in order to investigate the relations between soil cover, chemical properties, SSI and shrink-swell behaviour. Vegetation was associated with lower soil salinity and ESP, and higher soil organic matter content. Vegetated sites showed a higher SSI and a lower overall swelling. The shrinkage curves for samples from vegetated areas lack of the structural phase of shrinkage, likely due to the combined effect of lower ESP and the mechanical effect of plant roots. All soil properties and indicators point to a higher stability of soils under grass in the south aspect and under shrub in the north one.

Michele Perniola

2009-06-01

210

Shrinking Behaviour of Badland Soil Under Different Soil Covers  

Directory of Open Access Journals (Sweden)

Full Text Available Indicators used to estimate the soil structure stability facing erosion are the basis of major indicators of soil quality, and their behaviour is affected by permanent soil properties, vegetation and management. The relation between the pore-volume fraction occupied by water and the pore size distribution in clay soils is studied by the shrinkage curve describing clay soil porosity dynamics as a function of soil moisture. The aim of this work is to study the shrinking behaviour of the surface soil in a badland site through the shrinkage curve and to assess its relations with vegetation. Six treatments with different soil vegetation cover and aspect were selected on a badland site in Pisticci (Southern Italy. Shrinkage curves were built from natural aggregates collected in the 0-10 cm soil depth. Soil stability under shaking in water was also determined, with pre-treatments in water, alcohol and benzene for the determination of the SSI (Soil Stability Index. Soil organic matter, electrical conductivity, ESP were determined in order to investigate the relations between soil cover, chemical properties, SSI and shrink-swell behaviour. Vegetation was associated with lower soil salinity and ESP, and higher soil organic matter content. Vegetated sites showed a higher SSI and a lower overall swelling. The shrinkage curves for samples from vegetated areas lack of the structural phase of shrinkage, likely due to the combined effect of lower ESP and the mechanical effect of plant roots. All soil properties and indicators point to a higher stability of soils under grass in the south aspect and under shrub in the north one.

Michele Perniola

2011-02-01

211

Soils and the soil cover of the Valley of Geysers  

Science.gov (United States)

The results of field studies of the soil cover within the tourist part of the Valley of Geysers in Kamchatka performed in 2010 and 2011 are discussed. The morphology of soils, their genesis, and their dependence on the degree of hydrothermal impact are characterized; the soil cover patterns developing in the valley are analyzed. On the basis of the materials provided by the Kronotskii Biospheric Reserve and original field data, the soil map of the valley has been developed. The maps of vegetation conditions, soil temperature at the depth of 15 cm, and slopes of the surface have been used for this purpose together with satellite imagery and field descriptions of reference soil profiles. The legend to the soil map includes nine soil units and seven units of parent materials and their textures. Soil names are given according to the classification developed by I.L. Goldfarb (2005) for the soils of hydrothermal fields. The designation of soil horizons follows the new Classification and Diagnostic System of Russian Soils (2004). It is suggested that a new horizona thermometamorphic horizon TRMcan be introduced into this system by analogy with other metamorphic (transformed in situ) horizons distinguished in this system. This horizon is typical of the soils partly or completely transformed by hydrothermal impacts.

Kostyuk, D. N.; Gennadiev, A. N.

2014-06-01

212

Soil mechanics and analysis of soils overlying cavitose bedrock  

International Nuclear Information System (INIS)

The stability of the residual soils existing at the West Chestnut Ridge Site, Oak Ridge Reservation, Tennessee, was evaluated. The weathered bedrock below this residual soil contains numerous solution cavities, and several karst features were identified. The West Chestnut Ridge site was evaluated with respect to deformation and collapse of the residual soil into the bedrock cavities. A finite element analysis investigated the effects of bedrock cavity radius, thickness of soil overburden, and surface surcharge upon the deformational and stability characteristics of the residual soil. The results indicate that for small cavity radii, the thickness of the soil cover has little effect on the zone of yielded soil. For large cavity radii, a smaller zone of distressed soil occurs under thick soil cover than under thin soil cover. Dimensionless curves are presented to enable the prediction of the vertical extent of the zone of yielded soil for a range of site geometries. Although the thick soil deposits (100 feet or greater) typically found on the ridges result in high stresses adjacent to the cavity, the area of the distressed or yielded soil is small and unlikely to extend to the surface. In addition, the surface deformation or subsidence is expected to be minimal. Thus, the siting of waste facilities on the ridges where the overburden is maximum would tend to reduce the effects of deformation into the cavities. 29 refs., 37 figs., 7 tabs

213

University of Florida: Soil Texture  

Science.gov (United States)

This University of Florida website educates the public about soil texture, which is the distribution of sizes of mineral particles found in soils. After learning the basics about soil separates, students and educators can learn about the USDA textural triangle and the characteristics of the twelve textural classes. Researchers can discover how to determine the correct soil texture in the field. The website addresses the important role soil textures play in the determination of proper land use activities and management practices. Visitors will also find a short discussion about other factors that affect the behavior and qualities of soils.

214

Lasagna trademark soil remediation  

International Nuclear Information System (INIS)

Lasagna trademark is an integrated, in situ remediation technology being developed which remediates soils and soil pore water contaminated with soluble organic compounds. Lasagna trademark is especially suited to sites with low permeability soils where electroosmosis can move water faster and more uniformly than hydraulic methods, with very low power consumption. The process uses electrokinetics to move contaminants in soil pore water into treatment zones where the contaminants can be captured and decomposed. Initial focus is on trichloroethylene (TCE), a major contaminant at many DOE and industrial sites. Both vertical and horizontal configurations have been conceptualized, but fieldwork to date is more advanced for the vertical configuration. Major features of the technology are electrodes energized by direct current, which causes water and soluble contaminants to move into or through the treatment layers and also heats the soil; treatment zones containing reagents that decompose the soluble organic contaminants or adsorb contaminants for immobilization or subsequent removal and disposal; and a water management system that recycles the water that accumulates at the cathode (high pH) back to the anode (low pH) for acid-base neutralization. Alternatively, electrode polarity can be reversed periodically to reverse electroosmotic flow and neutralize pH

215

Microwave backscatter dependence on surface roughness, soil moisture, and soil texture. II - Vegetation-covered soil  

Science.gov (United States)

Results are presented for an experimental investigation to determine the relationship between radar backscatter coefficient (sigma) and soil moisture for vegetation-covered soil. These results extend a previous report which showed the experimental relationship between sigma and soil moisture for bare soil. It is shown that the highest correlation between sigma and soil moisture is 0.92 for the combined response of four crop types measured at 4.25 GHz, 10 deg incidence angle, and HH polarization. Radar look direction, relative to the crop row direction, is shown to have an insignificant effect on soil-moisture estimation if the radar frequency is higher than 4 GHz. The dependence on soil type can be minimized by expressing soil moisture in units of percent of field capacity. The possibility of using a single radar for measuring soil moisture for both bare and vegetated fields is demonstrated with a linear estimation algorithm having an experimental correlation coefficinet of 0.8.

Ulaby, F. T.; Bradley, G. A.; Dobson, M. C.

1979-01-01

216

Soil Genesis and Development, Lesson 5 - Soil Classification and Geography  

Science.gov (United States)

This lesson discusses the characteristics of the 12 soil orders defined by the USDA soil classification system, the major factors involved with their formation, and their geographic distribution across the USA and the world.

217

Predicting Radiocaesium Sorption with Soil Chemical Properties in Japanese Soils  

Energy Technology Data Exchange (ETDEWEB)

The soil-to-plant transfer mechanism of radiocaesium ({sup 137}Cs) in the Fukushima accident affected area is not fully understood. The sorption of {sup 137}Cs in soils holds a key to evaluating the variation of transfer of {sup 137}Cs to plant among different soil types. This study aims to investigate how differences in {sup 137}Cs adsorption in different soils can be explained by soil chemical and mineralogical properties. The Radiocaesium Interception Potential (RIP), a parameter for quantifying immediate {sup 137}Cs adsorption, and the soil texture were determined for 52 surface soils covering a wide range of texture classes collected from the area contaminated by the Fukushima accident. These soils include Andosols, Fluvisols, Gleysols, and Cambisols. In addition, we are currently performing analyses for other soil chemical properties (i.e. exchangeable cation, CEC, pH, organic matter content, etc) and for the properties affecting {sup 137}Cs sorption in soils (i.e. Frayed Edge Site capacity, K{sup +} and NH{sub 4}{sup +} selectivity, effect of wet-dry cycles, etc). The average RIP varied from 80 to 4300 mmol kg{sup -1} between soils. Contrary to what was found for temperate region soils by Absalom et al., the RIP (log(RIP)) and soil clay content were not significantly correlated (R2= 0.066). These initial results seem to indicate that the {sup 137}Cs sorption is affected by the clay mineralogy in soils. We postulate that by considering also the differences in clay K content, the relationship will improve since the frayed edges are formed at high K content in the clay. This knowledge could improve the prediction of RIP for different Japanese soil groups. Further analysis of the data will explore the relationship between RIP and other soil chemical properties. In our study, we will take specific note of Andosols (range of average RIP from 80 to 2400 mmol kg{sup -1}), typical soils in Japan originated from volcanic ash. It is expected that soil properties ruling the {sup 137}Cs sorption for Japanese Andosols will differ compared to other temperate mineral soils, for which most {sup 137}Cs transfer studies have been performed after the Chernobyl accident. We start by investigating the role of amorphous Al and Fe in {sup 137}Cs sorption. We believe that our findings could contribute to improved predictions of soil-to-plant transfer in Japanese soils and to the development of feasible countermeasures to reduce {sup 137}Cs transfer to plants for different soil-crop combinations in Japan. (authors)

Uematsu, Shinichiro [SCK.CEN, Belgian Nuclear Research Centre, Boeretang 200, B-2400 Mol (Belgium); Faculty of Bioscience Engineering, Katholieke Universiteit Leuven, Kasteelpark Arenberg 20, B-3001 Leuven (Belgium); Van Hees, May; Wannijn, Jean; Sweeck, Lieve; Vandenhove, Hildegarde [SCK.CEN, Belgian Nuclear Research Centre, Boeretang 200, B-2400 Mol (Belgium); Smolders, Erik [Faculty of Bioscience Engineering, Katholieke Universiteit Leuven, Kasteelpark Arenberg 20, B-3001 Leuven (Belgium)

2014-07-01

218

Predicting Radiocaesium Sorption with Soil Chemical Properties in Japanese Soils  

International Nuclear Information System (INIS)

The soil-to-plant transfer mechanism of radiocaesium (137Cs) in the Fukushima accident affected area is not fully understood. The sorption of 137Cs in soils holds a key to evaluating the variation of transfer of 137Cs to plant among different soil types. This study aims to investigate how differences in 137Cs adsorption in different soils can be explained by soil chemical and mineralogical properties. The Radiocaesium Interception Potential (RIP), a parameter for quantifying immediate 137Cs adsorption, and the soil texture were determined for 52 surface soils covering a wide range of texture classes collected from the area contaminated by the Fukushima accident. These soils include Andosols, Fluvisols, Gleysols, and Cambisols. In addition, we are currently performing analyses for other soil chemical properties (i.e. exchangeable cation, CEC, pH, organic matter content, etc) and for the properties affecting 137Cs sorption in soils (i.e. Frayed Edge Site capacity, K+ and NH4+ selectivity, effect of wet-dry cycles, etc). The average RIP varied from 80 to 4300 mmol kg-1 between soils. Contrary to what was found for temperate region soils by Absalom et al., the RIP (log(RIP)) and soil clay content were not significantly correlated (R2= 0.066). These initial results seem to indicate that the 137Cs sorption is affected by the clay mineralogy in soils. We postulate that by considering also the differences in clay K content, the relationship will improve since the frayed edges are formed at high K content in the clay. This knowledge could improve the prediction of RIP for different Japanese soil groups. Further analysis of the data will explore the relationship between RIP and other soil chemical properties. In our study, we will take specific note of Andosols (range of average RIP from 80 to 2400 mmol kg-1), typical soils in Japan originated from volcanic ash. It is expected that soil properties ruling the 137Cs sorption for Japanese Andosols will differ compared to other temperate mineral soils, for which most 137Cs transfer studies have been performed after the Chernobyl accident. We start by investigating the role of amorphous Al and Fe in 137Cs sorption. We believe that our findings could contribute to improved predictions of soil-to-plant transfer in Japanese soils and to the development of feasible countermeasures to reduce 137Cs transfer to plants for different soil-crop combinations in Japan. (authors)

219

Soil moisture distribution over time in a clay loam soil in Kosovo  

OpenAIRE

Studying the soil moisture distribution over time in a given soil profile is the object of the present study. The way the soil moisture gets distributed over soil profile depends particularly on the soil texture and on the soil suction gradients developed. However, it changes continuously over time for a given soil depth. The method of determining the soil moisture distribution over time is based on the measuring of soil moisture suctions developed and the soil moisture contents in various ti...

Abdullah Nishori; Besnik Gjongecaj; Deme Abazi

2013-01-01

220

Soil fungi as indicators of pesticide soil pollution  

OpenAIRE

Soil fungi, with their pronounced enzymic activity and high osmotic potential, represent a significant indicator of negative effects of different pesticides on the agroecosystem as a whole. In that respect, a trial was set up on the alluvium soil type with the aim to investigate the effect of different herbicides (Simazine, Napropamid, Paraquat), fungicides (Captan and Mancozeb) and insecticides (Fenitrothion and Dimethoate) on a number of soil fungi under apple trees. The number of soil fung...

Mandi? Leka; ?uki? Dragutin; ?or?evi? Sneana

2005-01-01

221

Terrain attribute soil mapping for predictive continuous soil property maps  

OpenAIRE

The current U.S. Soil Survey information is provided in polygon map units with soil property attributes represented with overlapping ranges between map units. The polygon maps do not represent the soil continuum that conforms to the actual landscape and the soil scientist expert knowledge accumulated during the field survey. Geographic Information System (GIS) technologies and software in combination with high resolution spatial data provide an opportunity to generate continuous raster based ...

Libohova, Zamir

2010-01-01

222

SOIL AND LEACHED BLACK SOIL ENVIRONMENTAL EVALUATION OF WEST CAUCASUS ????????-????????????? ?????? ????????? ????????????? ????????? ????????????  

Directory of Open Access Journals (Sweden)

Full Text Available The analysis of foreign and domestic methods to evaluate soil productivity sowings has been presented. It has shown the need for soil environmental assessment in the West Central Caucasus. The soil-environmental index and index scores for an experimental field of individual crops rotation, which will promptly assess the fertility of the soil, give recommendations for rational allocation of fertilizer has been given

Slyusarev V. N.

2013-05-01

223

Wood-soil interactions in soil bioengineering slope stabilization works  

OpenAIRE

In this work we propose the use of soil quality indicators with the aim of assessing the environmental impact of soil bioengineering works. This study was carried out in central Italy where soil bioengineering slope stabilization works were established using chestnut wood. In particular the goal of this study was to determine the occurrence of a wood-effect, that is changes of soil properties due to the presence of decomposing logs in two sites characterized by different time span since works...

Mc, Moscatelli; Romagnoli M; Cenfi S; Lagomarsino A; Di Tizio A; Spina S; Grego S

2009-01-01

224

Radon mitigation in soils  

International Nuclear Information System (INIS)

Radon is produced in soil by radium decay, Ra-226 for radon (Rn-222) and Ra-224 for thoron (Rn-220). The radium content is about 40 Bq.kg-1 in crustal rocks and soils, 70 Bq.kg-1 in granite and only about 8 Bq.kg-1 in limestone. Being the heaviest gas in atmosphere, radon presents high concentration at surface and it is accumulating in closed or poorly ventilated places, both in underground cavities (caves or mines) and in dwelling. In comparison with the average radon concentration in atmospheric air of 8 Bq.m-3, the average indoor radon concentration reaches 10-100 Bq.m-3. International statistics indicate that radon contribution on natural irradiation is about 60%. The main sources of indoor radon are: radium content of the soil and of the concretes, water supply and natural gases

225

A Laboratory Exercise Relating Soil Energy Budgets to Soil Temperature  

Science.gov (United States)

Enrollment by students in degree programs other than traditional horticulture, agronomy, and soil science has increased in basic plant and soil science courses. In order to broaden the appeal of these courses to students from majors other than agriculture, we developed a hands-on laboratory exercise relating the basic concepts of a soil energy

Koenig, Richard T.; Cerny-Koenig, Teresa; Kotuby-Amacher, Janice; Grossl, Paul R.

2008-01-01

226

Soil Genesis and Development, Lesson 5 - Soil Geography and Classification  

Science.gov (United States)

The system of soil classification developed by the United States Department of Agriculture (USDA) is called Soil Taxonomy. Soil Taxonomy consists of a hierarchy of six levels which, from highest to lowest, are: Order, Suborder, Great Group, Subgroup, family, and series. This lesson will focus on bro...

227

Soil and ground cover  

International Nuclear Information System (INIS)

The monitoring programmes set up in accordance with the directives for the surveillance of effluents from nuclear installations oblige operators of such installations to take samples of vegetation (grass) and soil twice a year at the least favourable place in the industrial plant's environment, and at a reference site, for radioactivity monitoring by gamma spectroscopy. In addition, the samples are to be examined for their Sr-90 content. Data recorded over the years show that nuclear facilities do not significantly contribute to soil and vegetation contamination with Sr-90 or Cs-137. The directives require regular interlaboratory comparisons, which are coordinated by the directing centre at Kiel. (DG)

228

Elementary GLOBE: Soil Treasure Hunt  

Science.gov (United States)

A learning activity for the Scoop on Soils book in the Elementary GLOBE Series. Students will make predictions about what they think they will find in a sample of soil. They will investigate the sample and sort out the various items they find. Next they will spend time outside observing one or more sites to see what they find in the soil. After recording and sharing their observations they will create their own stories about the things they found in the soil. The purpose of the activity is to learn about natural things commonly found in soil and how these things impact how the soil looks and feels as well as to introduce students to the concept of decomposition. After completing this activity, students will know about various things found in soil including rocks, critters, roots, and other organic material. They will also understand that animals and microorganisms aid in the decomposition process that contributes organic materials to soils.

2008-12-01

229

Soil texture; 1 : 500 000  

International Nuclear Information System (INIS)

The characteristics of soil texture are based on an abundant database of the agricultural and forest soils. The character of the texture of the upper soil horizons is assessed. The colour scale represents the classes of texture, and the raster distinguishes the individual classes of stoniness (in mountain ranges) or graveliness in the river alluvia. Soils with at least 10 % of area representation of rock basement are classified as very rocky. Very rocky soils are mostly rankers to Lithosols in the mountain areas of Slovakia. Medium stony are Cambisols to rankers on the crystalline rocks and volcanic complexes. The relatively heaviest soils are to be found in the Vychodoslovenska nizina Lowland, the lightest soils occur in the Zahorska nizina Lowland with prevalence of soils on aeolian sands. (authors)

230

Monitoring and evaluating soil quality  

OpenAIRE

This book provides a selection of microbiological methods that are already applied in regional or national soil quality monitoring programs. It is split into two parts: part one gives an overview of approaches to monitoring, evaluating and managing soil quality. Part two provides a selection of methods, which are described in sufficient detail to use the book as a practical handbook in the laboratory. The methods are described in chapters on soil microbial biomass and numbers, soil microbial ...

Bloem, J.; Schouten, A. J.; Srensen, S. J.; Rutgers, M.; Werf, A. K.; Breure, A. M.

2006-01-01

231

Agronomy / Soil Microbiology - Purdue University  

OpenAIRE

The graduate student interviewed for this data curation profile is studying studying the management strategies for bioenergy crops and their effect on soil structure and the sustainability of soil quality. She collects data on the soil structure and quality through a series of experiments and analysis to identify the effects of a particular soil treatment. Data management issues surround the use of a physical, rather than electronic, lab notebook that is hard to connect to the digital files t...

Carlson, Jake R.

2011-01-01

232

Decomposition of soil organic matter  

OpenAIRE

The climate is changing and with it the capacity of soils to store carbon in all likelihood, since there is strong evidence that decomposition increases with increasing temperature. The soil contains about twice as much carbon as the atmosphere, so decreasing soil carbon will increase atmospheric CO? concentrations proportionally more, further contributing to temperature increase. Different types of soil carbon may respond differently to climate change. A central theory in explaining temper...

Wetterstedt, Martin

2010-01-01

233

Persistence of benomyl in soil  

International Nuclear Information System (INIS)

Using 14C labelled benomyl, it has been shown that rapid degradation, as indicated by decrease in radioactivity in the acetone extract, occurred within 15 days in unsterilised soil while the process was not so rapid in sterilised soil. Fusarium solani, an important soil borne pathogen, has been found to be capable of detoxifying the fungicide in soil. With rise in temperature, increase in degradation of benomyl was observed, maximum being at 35deg C. (auth.)

234

Engineering Significant of Swelling Soils  

OpenAIRE

This study describes some of the most important swelling characters of expansive soils when used as foundation materials to support various types of civil engineering structures. Expansive soils are considered among difficult foundation materials and expand upon wetting and shrink upon losing moisture. They are considered problematic soils for architectural and civil engineers. These types of soils may cause minor to major structural damages to pavements as well as buildings. It is therefore ...

Behzad Kalantari

2012-01-01

235

Soil carbon determination by thermogravimetrics  

OpenAIRE

Determination of soil constituents and structure has a vital role in agriculture generally. Methods for the determination of soil carbon have in particular gained greater currency in recent times because of the potential that soils offer in providing offsets for greenhouse gas (CO2-equivalent) emissions. Ideally, soil carbon which can also be quite diverse in its makeup and origin, should be measureable by readily accessible, affordable and reliable means. Loss-on-ignition is still a widely u...

Robert Pallasser; Budiman Minasny; Mcbratney, Alex B.

2013-01-01

236

Soil Erosion Control After Wildfire  

Science.gov (United States)

The potential for severe soil erosion is a consequence of wildfire because as a fire burns it destroys important plant material and the litter layer that stabilizes soil and slows water movement after severe rainstorms. This information sheet discusses how intense heat from fire can make soils hydrophobic, or water repellent, and identifies the actions landowners can take to minimize erosion after a fire.

237

Soil carbon: Resisting climate change  

Science.gov (United States)

Increasing temperatures are expected to increase decomposition rates in soils, potentially reducing ecosystem carbon storage. Research now indicates that -- in a tropical montane forest -- soil carbon stocks are unaffected by higher temperatures despite substantially increased rates of CO2 release from the soil.

Hartley, Iain P.

2014-09-01

238

The Science of Soil Textures  

Science.gov (United States)

Off-road motorcycle racing and ATV riding. Gardening and fishing. What do these high-adrenaline and slower-paced pastimes have in common? Each requires soil, and the texture of that soil has an effect on all of them. In the inquiry-based lessons described here, students work both in the field or laboratory and in the classroom to collect soil

Bigham, Gary

2010-01-01

239

SOIL PHYSICS AND HYDROLOGY: CONDITIONERS  

Science.gov (United States)

Soil conditioners have been used since ancient times, even before the chemical and physical basis of conditioner effectiveness was accurately understood. Soil conditioners have included both organic and mineral materials as well as natural and synthetic materials. Examples of natural organic soil ...

240

Soil-Transmitted Helminth Infections  

Science.gov (United States)

Soil-transmitted helminth infections Fact sheet N366 Updated April 2014 Key facts Soil-transmitted helminth infections are caused by different species ... eggs present in human faeces, which contaminate the soil in areas where sanitation is poor. Approximately two ...

241

SOIL SURVEY GEOGRAPHIC DATABASE (SSURGO)  

Science.gov (United States)

This data set is a digital soil survey and is the most detailed level of soil geographic data developed by the National Cooperative Soil Survey. This data set consists of georeferenced digital map data and computerized attribute data. The map data are in a 7.5 minute quadrangle ...

242

Tannins Influence Soil Chemical Processes  

Science.gov (United States)

Tannins, plant secondary compounds, can affect soil and water quality by interacting with inorganic and organic compounds. However, the fate of tannins and their effect on soil metal cycling dynamics and soil chemical processes is poorly understood. We examined the effects of commercial available ...

243

Biochar addition impacts soil microbial community in tropical soils  

Science.gov (United States)

Studies on the effect of biochar on soil microbial activity and community structure in tropical areas are scarce. In this study we report the effect of several types of biochar (sewage sludge biochar, paper mill waste biochar, miscanthus biochar and pinewood biochar) in the soil microbial community of two tropical soils, an Acrisol and an Oxisol. In addition we study the effect of the presence or absence of earthworms in soil microbial community. Soil microbial community was more strongly affected by biochar than by the presence or absence of macrofauna.

Paz-Ferreiro, Jorge; Fu, Shenglei; Mndez, Ana; Gasc, Gabriel

2014-05-01

244

How soil shapes the landscape  

Science.gov (United States)

There has been an increase in interest in quantitative modelling of soil genesis, which can provide prediction of environmental changes through numerical models. Modelling soil formation is a difficult task because soil itself is highly complex with interactions between water, inorganic materials and organic matter. This paper will provide a review on the research efforts of modelling soil genesis, their connection with landscape models and the inexorable genesis of the IUSS soil landscape modelling working group. Quantitative modelling soil formation using mechanistic models have begun in the 1980s such as the 'soil deficit' model by Kirkby (1985), Hoosbeek & Bryant's pedodynamic model (1992), and recently the SoilGen model by Finke (2008). These profile models considered the chemical reactions and physical processes in the soil at the horizon and pedon scale. The SoilGen model is an integration of sub-models, such as water and solute movement, heat transport, soil organic matter decomposition, mineral dissolution, ion exchange, adsorption, speciation, complexation and precipitation. The model can calculate with detail the chemical changes and materials fluxes in a profile and has been successfully applied. While they can simulate soil profile development in detail, there is still a gap how the processes act in the landscape. Meanwhile research in landscape formation in geomorphology is progressing steadily over time, slope development models model have been developed since 1970s (Ahnert, 1977). Soil was also introduced in a landscape, however soil processes are mainly modelled through weathering and transport processes (Minasny & McBratney 1999, 2001). Recently, Vanwalleghem et al. (2013) are able to combine selected physical, chemical and biological processes to simulate a full 3-D soil genesis in the landscape. Now there are research gaps between the 2 approaches: the landscape modellers increasingly recognise the importance of soil and need more detailed soil processes, and the soil profile modellers need to consider material fluxes at the landscape scale. The IUSS working group (WG) on modelling of soil and landscape evolution has been recently proposed, accepted and established. The WG tries to engage scientists (landscape and pedon scale modellers, critical zone scientists, palaeopedologists, process-quantifying pedologists, and others) to work actively together towards a better soil-landscape model. Some aspects of the work include (i) improving ways to generate boundary conditions (climate, vegetation, human impacts) along the timeline, both at landscape and pedon scale; (ii) better model validation and its consequences for data collection; (iii) finding a more efficient simulation algorithms (iv) an inventory of the (mis-)match between present and needed process coverage to answer societal questions on soil behavior under global change.

Minasny, Budiman; Finke, Peter; Vanwalleghem, Tom Tom; Stockmann, Uta; McBratney, Alex

2014-05-01

245

Fresh Soil for Inspection  

Science.gov (United States)

The Mars Exploration Rover Opportunity dragged one of its wheels back and forth across the sandy soil at Meridiani Planum to create a hole (bottom of image) measuring approximately 50 centimeters (19.7 inches) long by 20 centimeters (7.9 inches) wide by 9 centimeters (3.5 inches) deep. The rover's instrument deployment device, or arm, will begin studying the fresh soil at the bottom of this trench later today for clues to its mineral composition and history. Scientists chose this particular site for digging because previous data taken by the rover's miniature thermal emission spectrometer indicated that it contains crystalline hematite, a mineral that sometimes forms in the presence of water. The brightness of the newly-exposed soil is thought to be either intrinsic to the soil itself, or a reflection of the Sun. The rock outcrop lining the inner edge of the small crater encircling the rover and lander can be seen on the horizon. This fish-eye image was taken by the rover's hazard-avoidance camera.

2004-01-01

246

Opportunity Trenches Martian Soil  

Science.gov (United States)

The Mars Exploration Rover Opportunity dragged one of its wheels back and forth across the sandy soil at Meridiani Planum to create a hole (bottom left corner) approximately 50 centimeters (19.7 inches) long by 20 centimeters (7.9 inches) wide by 9 centimeters (3.5 inches) deep. The rover's instrument deployment device, or arm, will begin studying the fresh soil at the bottom of this trench later today for clues to its mineral composition and history. Scientists chose this particular site for digging because previous data taken by the rover's miniature thermal emission spectrometer indicated that it contains crystalline hematite, a mineral that sometimes forms in the presence of water. The brightness of the newly-exposed soil is thought to be either intrinsic to the soil itself, or a reflection of the Sun. Opportunity's lander is in the center of the image, and to the left is the rock outcrop lining the inner edge of the small crater that encircles the rover and lander. This mosaic image is made up of data from the rover's navigation and hazard-avoidance cameras.

2004-01-01

247

Soil and Sediment Erosion  

Science.gov (United States)

This brief article discusses the effect of soil and sediment erosion and its significance in social and economic aspects. The methods of measuring erosion and knowledge of past erosion rates are also briefly discussed to use as a predictor of future erosion rates.

2008-09-22

248

Spirit Sees Salty Soil  

Science.gov (United States)

This graph compares amounts of magnesium and sulfur in the soil lining the trenches dug by the Mars Exploration Rover Spirit on sols 114 and 140 (April 28 and May 25, 2004) at Gusev Crater. Measurements were taken of the soil at the surface, floor and walls of the trench dug on sol 140 (squares), and at the surface and floor of the trench dug on sol 114 (diamonds). Non-trenched soil samples from Gusev Crater are represented as dots. The more recently made trench is located near the base of the 'Columbia Hills.' Because concentrations of magnesium and sulfur occur in the same ratio throughout the trench dug on sol 140, scientists believe the soil there contains the salt magnesium sulfate. The walls of this trench appear to contain the highest concentrations of the salt. The trench from sol 114 may also possess magnesium sulfate, but the data is less clear. These data were taken by Spirit's alpha particle X-ray spectrometer. One possible explanation for these findings is that water percolated through underground material and dissolved out minerals, then as the water evaporated near the surface, it left concentrated salts behind.

2004-01-01

249

Surface soil contamination standards  

International Nuclear Information System (INIS)

The purpose of this document is to define surface soil contamination limits for radioactive materials below which posting, restrictions and environmental controls are not necessary in order to protect personnel and the environment. The standards can also be used to determine if solid waste or other material is contaminated relative to disposal requirements. The derivation of the standards is given

250

Remediation for contaminated soils  

Energy Technology Data Exchange (ETDEWEB)

A versatile remediation centre for contaminated soils has operated at Virkkala close to Helsinki since 1998. It is the first regional soil remediation centre in Finland and serves a large area in south- western Finland. Contaminated soils are collected from tens of small and large sites each year and transported to Virkkala for a very high class and environmentally safe treatment under controlled conditions. The centre consists of a 2 ha large hall for storage and treatment of the soils, a 1 ha outside bio-remediation field and a service and truck washing hall. Three treatment technologies are available at the centre: Stabilization/solidification, washing and bio-remediation. With these methods all the most common types of contamination can be treated: Heavy metals, oils, PAHs, creosotes and chlorophenols. Special care has been taken with prevention of environmental emissions, because the centre is located close to a housing area and on a lake-front. All the storage and treatment areas are covered with a double or triple bottom liner system and all environmental emissions are being monitored constantly. EU's Life Environment -fund has supported the project. (orig.)

Kivekaes, L. [Lohja Envirotec, Helsinki (Finland)

2000-07-01

251

Soils. Transparency Masters.  

Science.gov (United States)

This document is a collection of 43 overhead transparency masters to be used as teaching aids in a course of study involving soils such as geology, agronomy, hydrology, earth science, or land use study. Some transparencies are in color. Selected titles of transparencies may give the reader a better understanding of the graphic content. Titles are:

Clemson Univ., SC. Vocational Education Media Center.

252

Wood-soil interactions in soil bioengineering slope stabilization works  

Directory of Open Access Journals (Sweden)

Full Text Available In this work we propose the use of soil quality indicators with the aim of assessing the environmental impact of soil bioengineering works. This study was carried out in central Italy where soil bioengineering slope stabilization works were established using chestnut wood. In particular the goal of this study was to determine the occurrence of a wood-effect, that is changes of soil properties due to the presence of decomposing logs in two sites characterized by different time span since works setting up. The presence of the logs did not affect soil physico-chemical properties. Conversely, soil biochemical properties such as soil microbial biomass, basal and cumulative respiration activities as well as microbial indexes, were influenced by the presence of the logs confirming the role of these bioindicators as early predictors of changes occurring in soil. Although a general positive trend was observed for the biochemical properties at both sites with respect to the control soils, significant differences were recorded mainly at the site where works were established six years before soil sampling. Soil bioengineering slope stabilization works establish a positive feed-back which ultimately can benefit plants; in fact the increase in microbial mineralization activity can enhance nutrient cycling and thus promote adequate growth conditions for the plant cuttings used in the wooden-work.

Moscatelli MC

2009-10-01

253

MINIRHIZOTRON INSTALLATION IN SANDY, ROCKY SOILS WITH MINIMAL SOIL DISTRUBANCE  

Energy Technology Data Exchange (ETDEWEB)

We developed and demonstrated the utility of a technique for installing minirhizotron tubes in sandy, rocky soils where more traditional installation methods are inadequate. The method uses a pneumatic rock-drill alternately to drill and drive drill casing into the soil. Soil particles and drilling debris are removed from the casing as it is installed. The minirhizotron tube is inserted into the drill casing and the casing is withdrawn. A pneumatic screw-drive guide system powers the downward and upward movement of the rock-drill and controls the angle of installation. Working from a platform suspended from a center-pivot elevated catwalk minimized soil disturbance. Soil contact and root ingrowth around the minirhizotron tubes were very satisfactory. This method, while fairly labor intensive, allows minirhizotron studies of root dynamics in sandy, rocky soils where they would otherwise not be possible. Also, there is much less soil compaction and disturbance than traditional installation techniques entail.

D.L. PHILLIPS; M. G. JOHNSON; D. T. TINGEY; CRAIG BIGGART; R. S. NOWAK; J. C. NEWSOM

2000-03-01

254

Soil moisture estimation with limited soil characterization for decision making  

Science.gov (United States)

Many decisions in agriculture are conditional to soil moisture. For instance in wet conditions, farming operations as soil tillage, organic waste spreading or harvesting may lead to degraded results and/or induce soil compaction. The development of a tool that allows the estimation of soil moisture is useful to help farmers to organize their field work in a context where farm size tends to increase as well as the need to optimize the use of expensive equipments. Soil water transfer models simulate soil moisture vertical profile evolution. These models are highly sensitive to site dependant parameters. A method to implement the mechanistic soil water and heat flow model (the TEC model) in a context of limited information (soil texture, climatic data, soil organic carbon) is proposed [Chanzy et al., 2008]. In this method the most sensitive model inputs were considered i.e. soil hydraulic properties, soil moisture profile initialization and the lower boundary conditions. The accuracy was estimated by implementing the method on several experimental cases covering a range of soils. Simulated soil moisture results were compared to soil moisture measurements. The obtained accuracy in surface soil moisture (0-30 cm) was 0.04 m3/m3. When a few soil moisture measurements are available (collected for instance by the farmer using a portable moisture sensor), significant improvement in soil moisture accuracy is obtained by assimilating the results into the model. Two assimilation strategies were compared and led to comparable results: a sequential approach, where the measurement were used to correct the simulated moisture profile when measurements are available and a variational approach which take moisture measurements to invert the TEC model and so retrieve soil hydraulic properties of the surface layer. The assimilation scheme remains however heavy in terms of computing time and so, for operational purposed fast code should be taken to simulate the soil moisture as with the Ross model [Ross, 2003, Crevoisier et al, 2009]. To meet the decision support context, we evaluated the model ability of evaluating the soil moisture level in comparison to a moisture threshold that splits soil conditions into desirable and undesirable cases. This threshold depends on soil properties, the farming operation and equipment characteristics. We evaluate the rate of making good decisions using either the TEC model with and without soil moisture measurements or an empirical algorithm that simulate the decision processes followed by farmers, currently. This later is a reference case that allows appreciating the adding value of using soil water transfer models. We found a significant improvement with a rate of success, which increases from 65% with the reference case to 90% when using the model with soil moisture assimilation. Chanzy, A., Mumen M., Richard, G.. (2008), Accuracy of top soil moisture simulation using a mechanistic model with limited soil characterization, Water Resources Research, 44(3), W03432. Crevoisier, D., Chanzy, A., Voltz M. (2009), Evaluation of the Ross Fast Solution of Richards' Equation in Unfavourable Conditions for Standard Finite Element Methods, Advances in Water Ressources, In revision. Ross, P. J. (2003). Modeling soil water and solute transport - Fast, simplified numerical solutions. Agronomy Journal 95:1352-1361.

Chanzy, A.; Richard, G.; Boizard, H.; Dfossez, P.

2009-04-01

255

[Effects of nitrogen fertilization, soil moisture and soil temperature on soil respiration during summer fallow season].  

Science.gov (United States)

On the loess plateau, summer fallow season is a hot rainy time with intensive soil microbe activities. To evaluate the response of soil respiration to soil moisture, temperature, and N fertilization during this period is helpful for a deep understanding about the temporal and spatial variability of soil respiration and its impact factors, then a field experiment was conducted in the Changwu State Key Agro-Ecological Experimental Station, Shaanxi, China. The experiment included five N application rates: unfertilized 0 (N0), 45 (N45), 90 (N90), 135(N135), and 180 (N180) kg x hm(-2). The results showed that at the fallow stage, soil respiration rate significantly enhanced from 1.24 to 1.91 micromol x (m2 x s)(-1) and the average of soil respiration during this period [6.20 g x (m2 x d)(-1)] was close to the growing season [6.95 g x (m2 x d)(-1)]. The bivariate model of soil respiration with soil water and soil temperature was better than the single-variable model, but not so well as the three-factor model when explaining the actual changes of soil respiration. Nitrogen fertilization alone accounted for 8% of the variation soil respiration. Unlike the single-variable model, the results could provide crucial information for further research of multiple factors on soil respiration and its simulation. PMID:22295609

Zhang, Fang; Guo, Sheng-Li; Zou, Jun-Liang; Li, Ze; Zhang, Yan-Jun

2011-11-01

256

Nitrification in Dutch heathland soils.  

OpenAIRE

This thesis is the result of a study on the production of nitrate in Dutch heathland soils. Most of the heathlands are located on acid, sandy soils. Therefore , it has dealt mainly with the occurrence, nature and mechanisms of nitrification in acid soils. In the Netherlands, the production of nitrate in acid soils is a matter of great concern because it has become obvious that this process contributes to a continuous acidification of such soils that are exposed to high levels of deposition of...

Boer, W.

1989-01-01

257

Acid Rain Experiments: Soil Buffering  

Science.gov (United States)

This experiment will help students understand that soil sometimes contains substances, like limestone, that buffer acids or bases, and that some salts in soil may also act as buffers. They will collect soil samples from their lawn, garden, or school and look for buffering effects by observing the pH change of an acid mixture poured through the samples. If the water collected from the sample is less acidic than the original mixture, then the soil is buffering some of the acid. If it does not change, then the soil may not be capable of buffering acids.

258

Mine soil classification and mapping  

International Nuclear Information System (INIS)

This presentation covers the history of surface coal mining and reclamation methods and equipment for the pre-Federal law, interim-Federal law, and post-Federal law periods. It discusses the difficulties with traditional mine soil mapping methods on five soils series in Illinois. These methods fail to recognize the effects of compaction and methods to ameliorate compaction. The current status of mine soil mapping methods on eight soil series in Illinois are presented. Areas where additional work is needed and future potential difficulties are identified for mine soil mapping efforts

259

Remote assessment of soil moisture  

International Nuclear Information System (INIS)

Soil moisture can be estimated in the upper few centimeters of the soil profile by three separate remote sensing techniques. The simplest and least costly method uses the ratio of reflected to incoming solar radiation (albedo). Just as simple, but more costly for equipment, is the use of emitted thermal radiation. Surface soil temperature and air temperature are the only measurements required to estimate water content near the soil surface. Both active and passive microwave techniques can be used to infer soil water content, potentially to depths of 10 cm; however, they require more sophisticated and bulky equipment than the other two methods. (author)

260

Spatial and temporal variability of soil electrical conductivity related to soil moisture  

OpenAIRE

Soil electrical conductivity (ECa) is a soil quality indicator associated to attributes interesting to site-specific soil management such as soil moisture and texture. Soil ECa provides information that helps guide soil management decisions, so we performed spatial evaluation of soil moisture in two experimental fields in two consecutive years and modeled its influence on soil ECa. Soil ECa, moisture and clay content were evaluated by statistical, geostatistical and regression analyses. Semiv...

Jos Paulo Molin; Gustavo Di Chiacchio Faulin

2013-01-01

261

Effects of environmental factors and soil properties on topographic variations of soil respiration  

OpenAIRE

Soil respiration rates were measured along different parts of a slope in (a) an evergreen forest with common brown forest soil and (b) a deciduous forest with immature soil. The effects of soil temperature, soil moisture and soil properties were estimated individually, and the magnitudes of these effects in the deciduous and evergreen forests were compared. In the evergreen forest with common brown forest soil, soil properties had the greatest effect on soil respiration rates, followed by soi...

Tamai, K.

2010-01-01

262

Communicating soil property variability in heterogeneous soil mapping units  

Science.gov (United States)

Soil properties and classes can change over very short distances. For the purpose of scale, clarity and field sampling density, soil maps in England and Wales commonly use mapping units which are groupings of taxonomic soil series, commonly found in association with each other in the landscape. These mixed units (Soil Associations), typically contain between 3 and 7 soil series with physical or chemical properties, which can vary across the mapping unit, or may be relatively homogeneous. The degree of variation is not constant between soil properties, for instance, pH may be relatively constant, but volumetric shrinkage potential may be highly variable. Over the past ten years, the number of users of GIS soil property maps has dramatically increased, yet the vast majority of these users do not have a soil or geoscience background. They are instead practitioners in specific industries. As a result, new techniques have been developed to communicate the variation in maps of soil properties to a non-expert audience. GIS data structures allow more flexibility in the reporting of uncertainty or variation in soil mapping units than paper-based maps. Some properties are categorical, others continuous. In England and Wales, the national and regional memberships of soil associations are available, with areal percentages of the comprising soil series being estimated for each association by a combination of expert judgment and field observations. Membership at a local scale can vary considerably from the national average. When summarizing across a whole map unit, for continuous variables, rarely is it appropriate to provide a mean value, or even a weighted average based on membership percentage of the association. Such approaches can make a nonsense of wide-ranging data. For instance a soil association comprising soil series with highly different percentages of sand, silt and clay may result in a 'loamy' mean soil texture which is not reflective of any of the comprising soils. For categorical data, the choice of the property of the spatially dominant soil series may provide the 'most likely' answer, but this may not be the most helpful answer for the end user. Additionally, when aggregating to select the dominant property or class, rather than the dominant taxonomic soil series, it is not uncommon for the 'dominant' class to change. One example of our new approach is to communicate the attributes of the soil associations on the basis of the worst-case scenario at various confidence levels, based on the percentage of the soil series of the association. As an example, when soil maps are used to help underwriters understand the vulnerability of an area to soil related subsidence, the maximum subsidence rating can be chosen from soils which comprise, for example, more than 5% or more than 30% of the soil association in question. Developing an understanding of end-user requirements allows optimization of soil datasets to suit their needs, and encourages engagement between soil scientists and industry.

Farewell, Timothy

2014-05-01

263

Dynamical soil-structure interactions: influence of soil behaviour nonlinearities  

International Nuclear Information System (INIS)

The interaction of the soil with the structure has been largely explored the assumption of material and geometrical linearity of the soil. Nevertheless, for moderate or strong seismic events, the maximum shear strain can easily reach the elastic limit of the soil behavior. Considering soil-structure interaction, the nonlinear effects may change the soil stiffness at the base of the structure and therefore energy dissipation into the soil. Consequently, ignoring the nonlinear characteristics of the dynamic soil-structure interaction (DSSI) this phenomenon could lead to erroneous predictions of structural response. The goal of this work is to implement a fully nonlinear constitutive model for soils into a numerical code in order to investigate the effect of soil nonlinearity on dynamic soil structure interaction. Moreover, different issues are taken into account such as the effect of confining stress on the shear modulus of the soil, initial static condition, contact elements in the soil-structure interface, etc. During this work, a simple absorbing layer method based on a Rayleigh/Caughey damping formulation, which is often already available in existing Finite Element softwares, is also presented. The stability conditions of the wave propagation problems are studied and it is shown that the linear and nonlinear behavior are very different when dealing with numerical dispersion. It is shown that the 10 points per wavelength rule, recommended in the literature for the elastic media is not sufficient for the nonlinear case. The implemented model is first numerically verified by comparing the results with other known numerical codes. Afterward, a parametric study is carried out for different types of structures and various soil profiles to characterize nonlinear effects. Different features of the DSSI are compared to the linear case: modification of the amplitude and frequency content of the waves propagated into the soil, fundamental frequency, energy dissipation in the soil and the response of the soil-structure system. Through these parametric studies we show that depending on the soil properties, frequency content of the soil response could change significantly due to the soil nonlinearity. The peaks of the transfer function between free field and outcropping responses shift to lower frequencies and amplification happens at this frequency range. Amplification reduction for the high frequencies and even de-amplification may happen for high level input motions. These changes influence the structural response. We show that depending on the combination of the fundamental frequency of the structure and the the natural frequency of the soil, the effect of soil-structure interaction could be significant or negligible. However, the effect of structure weight and rocking of the superstructure could change the results. Finally, the basin of Nice is used as an example of wave propagation on a heterogeneous nonlinear media and dynamic soil-structure interaction. The basin response is strongly dependent on the combination of soil nonlinearity, topographic effects and impedance contrast between soil layers. For the selected structures and soil profiles of this work, the performed numerical simulations show that the shift of the fundamental frequency is not a good index to discriminate linear from nonlinear soil behavior. (author)

264

Soil Carbon Sequestration in India  

International Nuclear Information System (INIS)

With a large land area and diverse ecoregions, there is a considerable potential of terrestrial/soil carbon sequestration in India. Of the total land area of 329 million hectares (Mha), 297 Mha is the land area comprising 162 Mha of arable land, 69 Mha of forest and woodland, 11 Mha of permanent pasture, 8 Mha of permanent crops and 58 Mha is other land uses. The soil organic carbon (SOC) pool is estimated at 21 Pg (petagram = Pg = 1 x 1015 g billion ton) to 30-cm depth and 63 Pg to 150-cm depth. The soil inorganic carbon (SIC) pool is estimated at 196 Pg to 1-m depth. The SOC concentration in most cultivated soils is less than 5 g/kg compared with 15 to 20 g/kg in uncultivated soils. Low SOC concentration is attributed to plowing, removal of crop residue and other biosolids, and mining of soil fertility. Accelerated soil erosion by water leads to emission of 6 Tg C/y. Important strategies of soil C sequestration include restoration of degraded soils, and adoption of recommended management practices (RMPs) of agricultural and forestry soils. Potential of soil C sequestration in India is estimated at 7 to 10 Tg C/y for restoration of degraded soils and ecosystems, 5 to 7 Tg C/y for erosion control, 6 to 7 Tg C/y for adoption of RMPs on agricultural soils, and 22 to 26 Tg C/y for secondary carbonates. Thus, total potential of soil C sequestration is 39 to 49 (44 5) Tg C/y

265

Discovering the essence of soil  

Science.gov (United States)

Science, and what it can learn, is constrained by its paradigms and premises. Similarly, teaching and what topics can be addressed are constrained by the paradigms and premises of the subject matter. Modern soil science is founded on the five-factor model of Dokuchaev and Jenny. Combined with Retallack's universal definition of soil as geologic detritus affected by weathering and/or biology, modern soil science emphasizes a descriptive rather than an interpretive approach. Modern soil science however, emerged from the study of plants and the need to improve crop yields in the face of chronic and wide spread famine in Europe. In order to teach that dirt is fascinating we must first see soils in their own right, understand their behavior and expand soil science towards an interpretive approach rather than limited as a descriptive one. Following the advice of James Hutton given over two centuries ago, I look at soils from a physiological perspective. Digestive processes are mechanical and chemical weathering, the resulting constituents reformed into new soil constituents (e.g. clay and humus), translocated to different regions of the soil body to serve other physiological processes (e.g. lamellae, argillic and stone-line horizons), or eliminated as wastes (e.g. leachates and evolved gasses). Respiration is described by the ongoing and diurnal exchange of gasses between the soil and its environment. Circulatory processes are evident in soil pore space, drainage capacity and capillary capability. Reproduction of soil is evident at two different scales: the growth of clay crystals (with their capacity for mutation) and repair of disturbed areas such as result from the various pedo-perturbations. The interactions between biotic and abiotic soil components provide examples of both neurological and endocrine systems in soil physiology. Through this change in perspective, both biotic and abiotic soil processes become evident, providing insight into the possible behavior of ancient prebiotic soils. Furthermore, the physiological approach sheds light on the emergence of new soil components (e.g. spodic horizons) as ancient prebiotic soils adapt to a plethora of biotic carbon compounds. Other emergent soil properties and behaviors can be linked to the kinds, frequencies, order and intensities of various ubiquitous pedo-perturbations.

Frink, D.

2012-04-01

266

Soil physical properties on Venezuelan steeplands: Applications to soil conservation planning  

International Nuclear Information System (INIS)

This paper presents a framework to support decision making for soil conservation on Venezuelan steeplands. The general approach is based on the evaluation of two important land qualities: soil productivity and soil erosion risk, both closely related to soil physical properties. Soil productivity can be estimated from soil characteristics such as soil air-water relationships, soil impedances and soil fertility. On the other hand, soil erosion risk depends basically on soil hydrologic properties, rainfall aggressiveness and terrain slope. Two indexes are obtained from soil and land characteristics: soil productivity index (PI) and erosion risk index (ERI), each one evaluates the respective land quality. Subsequently, a matrix with these two qualities shows different land classes as well as soil conservation priorities, conservation requirements and proposed land uses. The paper shows also some applications of the soil productivity index as an approach to evaluate soil loss tolerance for soil conservation programs on tropical steeplands. (author)

267

Bioremediation of soils  

International Nuclear Information System (INIS)

Bioremediation of hydrocarbon contaminated soils has evolved from the refinery land treatment units of thirty years ago to the modern slurry reactors of today. Modifications in the process include engineering controls designed to prevent the migration of hydrocarbons into the unsaturated zone, the saturated zone and groundwater, and the atmosphere. Engineering innovations in the area of composting and bioaugmentation that have focused on further process control and the acceleration of the treatment process will form the basis for future improvements in bioremediation technology. Case studies for established methods that have survived this development process and continue to be used as cost effective biological treatments like engineered land farms, soil heap treatment and in situ treatment will be discussed

268

Soil column leaching of pesticides.  

Science.gov (United States)

In this review, I address the practical and theoretical aspects of pesticide soil mobility.I also address the methods used to measure mobility, and the factors that influence it, and I summarize the data that have been published on the column leaching of pesticides.Pesticides that enter the unsaturated soil profile are transported downwards by the water flux, and are adsorbed, desorbed, and/or degraded as they pass through the soil. The rate of passage of a pesticide through the soil depends on the properties of the pesticide, the properties of the soil and the prevailing environmental conditions.Because large amounts of many different pesticides are used around the world, they and their degradates may sometimes contaminate groundwater at unacceptable levels.It is for this reason that assessing the transport behavior and soil mobility of pesticides before they are sold into commerce is important and is one indispensable element that regulators use to assess probable pesticide safety. Both elementary soil column leaching and sophisticated outdoor lysimeter studies are performed to measure the leaching potential for pesticides; the latter approach more reliably reflects probable field behavior, but the former is useful to initially profile a pesticide for soil mobility potential.Soil is physically heterogeneous. The structure of soil varies both vertically and laterally, and this variability affects the complex flow of water through the soil profile, making it difficult to predict with accuracy. In addition, macropores exist in soils and further add to the complexity of how water flow occurs. The degree to which soil is tilled, the density of vegetation on the surface, and the type and amounts of organic soil amendments that are added to soil further affect the movement rate of water through soil, the character of soil adsorption sites and the microbial populations that exist in the soil. Parameters that most influence the rate of pesticide mobility in soil are persistence (DT50) of the pesticide, and its sorption/desorption(Koc) characteristics. These parameters may vary for the same pesticide from geographic site-to-site and with soil depth. The interactions that normally occur between pesticides and dissolved organic matter (DOM) or WDC are yet other factors that may complicate pesticide leaching behavior.The soil mobility of pesticides is normally tested both in the laboratory and in the field. Lab studies are initially performed to give researchers a preliminary appraisal of the relative mobility of a pesticide. Later, field lysimeter studies can be performed to provide more natural leaching conditions that emulate the actual field use pattern. Lysimeter studies give the most reliable information on the leaching behavior of a pesticide under field conditions, but these studies are time-consuming and expensive and cannot be performed everywhere. It is for this reason that the laboratory soil column leaching approach is commonly utilized to profile the mobility of a pesticide,and appraise how it behaves in different soils, and relative to other pesticides.Because the soil structure is chemically and physically heterogenous, different pesticide tests may produce variable DT50 and Koc values; therefore, initial pesticide mobility testing is undertaken in homogeneously packed columns that contain two or more soils and are eluted at constant flow rates. Such studies are done in duplicate and utilize a conservative tracer element. By fitting an appropriate mathematical model to the breakthrough curve of the conservative tracer selected,researchers determine key mobility parameters, such as pore water velocity, the column-specific dispersion coefficient, and the contribution of non equilibrium transport processes. Such parameters form the basis for estimating the probable transport and degradation rates that will be characteristic of the tested pesticide. Researchers also examine how a pesticide interacts with soil DOM and WDC, and what contribution from facilitated transport to mobility is made as a result of the effects of

Katagi, Toshiyuki

2013-01-01

269

Food, soil, and agriculture  

International Nuclear Information System (INIS)

The growing pressures on the world's land resources will result in problems requiring a major research effort.The first group of problems relates to increased soil degradation. The research to alleviate this will have to incorporate not only physical and biological solutions, but also pay much more attention to the socio-economic context in which the conservation programmes need to succeed.The second major area for research on land resource is to make better use of low-capacity or problem soils.This could be by reducing the existing limitations, such as changing physical or chemical characteristics of the soil, or by developing plants and production techniques which reduce the detrimental effects of constraints. Example of these are acidity, salinity, and aluminium toxicity. Finally the broadest and more important area is that of research to enable more intensive use of better-quality land. Research topics here may relate to optimal plant nutrient management, soil moisture management, and developing cultivation techniques with minimum commercial energy requirements. Making plants more productive will involve research aimed at increasing photosynthetic efficiency, nitrogen fixation, disease and pest resistance, improved weed control, and bio-engineering to adjust plant types to maximize production potentials. Improved rotational systems for the achievement of many of the above goals will become increasingly important, as the potential problems or inappropriate cultivattential problems or inappropriate cultivation practices become evident. In conclusion, food supplies of the world could meet the rapidly rising demands that are made on them, if agriculture receives sufficient attention and resources. Even with most modern development, land remains the base for agriculture, and optimal use of the world's land resources is thus crucial for future agricultural production

270

Directory of soil physicists  

Science.gov (United States)

The new International Directory of Soil Physicists, compiled by Philippe Baveye and Charles Boast (University of Illinois, Urbana), will be available in early June 1988. The directory has some 750 entries and a geographical index. It is not subject to copyright, may be freely duplicated, and will be updated annually. For more information, contact Philippe Baveye, Department of Agronomy , University of Illinois, 1102 South Goodwin Avenue, Urbana, IL 61801; telephone: 217-333-3420.

271

Fallout fractionation in silicate soils  

International Nuclear Information System (INIS)

The existing models for testing radiochemical fractionation in nuclear weapon debris are discussed and compared. A method which extends the existing theory for the case of surface bursts over silicate soils is developed and validated with weapons test data. There is evidence that fission product absorption by soil and weapon debris is diffusion controlled. There is also evidence that there are two superimposed distributions of soil particles. A portion of the soil is fully vaporized along with the weapon debris while some soil is merely melted. As the fireball cools, the refractory fission products will be absorbed by this liquid material. After the fireball has cooled below the soil solidification temperature, the remaining fission products can be adsorbed onto any available surfaces. Any soil which entered the fireball at the soil solidification time or later will also adsorb fission products. Test data and other evidence indicate that the distributions of melted and unmelted soil particles have different modes. This model uses Henry's Law to find surface concentrations. It then uses diffusion theory to transport the fission products into the particles. In addition, it allows for injection of unmelted material near the time of soil solidification. The results of the research indicate that in standard DELFIC calculations too much activity is carried in the larger particles and too little in the smaller particles

272

Soils and organic sediments  

International Nuclear Information System (INIS)

The organic component of soils is basically made up of substances of an individual nature (fats, waxes, resins, proteins, tannic substances, and many others), and humic substances (Kononova, 1966). These are complex polymers formed from breakdown products of the chemical and biological degradation of plant and animal residues. They are dark coloured, acidic, predominantly aromatic compounds ranging in molecular weight from less than one thousand to tens of thousands (Schnitzer, 1977). They can be partitioned into three main fractions:(i) Humic acid, which is soluble in dilute alkaline solution, but can be precipitated by acidification of the alkaline extract.(ii) Fulvic acid, which is soluble in alkaline solution, but is also soluble on acidification.(iii) Humin that cannot be extracted from the soil or sediment by dilute acid or alkaline solutions. It has mostly been assumed that the humic and fulvic acid components of the soil are part of the mobile, or 'active' component, and the humin component is part of the 'passive' component. Other types of organic sediments are likely to contain chemical breakdown products of plant material, plant fragments and material brought in from outside sources. The outside material can be contemporaneous with sediment deposition, can be older material, or younger material incorporated into the sediment long after deposition. Recognition of 'foreign' material is essential for dating, but is not an easy task. Examples of separation techniques for humic and non humic components are evaluated for their efficiency

273

Intercomparison measurement - Orava soil  

International Nuclear Information System (INIS)

In 1997 our laboratory organized intercomparison measurement in gamma spectrometry. The soil samples were delivered to 20 laboratories in 4 countries. The main aim was check the laboratory practice of member of the Slovak Radiation Monitoring Network. This summary contains the results of the intercomparison on the determination of radionuclides in soil by gamma spectrometry. The soil was collected in autumn 1996 near Namestovo (Orava region) from layer 0 -5 cm. Although data on 20 radionuclides were received, only data for 134Cs, 137Cs, 226Ra, 226Ra, 232Th and 40K were statistically evaluated. The received activities are (mean activity, [Bq/kg]; standard deviation, [Bq/kg]; range [Bq/kg]): for 134Cs: 1.05, 0.36, .0.31-1.85; for 137Cs: 59.7, 1.6, 57.5-62.7; for 226Ra: 24.0, 1.5, 21.8-26.9; for 232Th: 27.3, 2.8, 22.4-33.1; for 40K: 411, 39, 346-480. The used half-times and yields do not differ significantly. The differences between laboratories in reported results are due to mainly by sample treatment and spectra evaluation (used efficiency)

274

Radionuclide migration in soils  

International Nuclear Information System (INIS)

Unplanned releases from a nuclear installation - e.g., leakage from a storage tank or other incident - can result in the escape of contaminants such as U, Pu, Cs, Sr, T etc. Nuclide transport through the ground is governed by characteristics of the subsurface hydrology and the specific nuclides under consideration. Unsaturated soil layers result in a transport rate so low as to negligible. Radionuclides reaching the ground water are assumed to endanger human life because of potential uncontrolled ingestion. The most dangerous nuclides are long-lived and not absorbed, or very poorly absorbed, in the soil. During migration of nuclides through saturated soil layers, the concentration can be reduced by dilution. Preliminary results indicate that tritium is spread with ground water velocity. Its concentration can be reduced only by diffusion, dispersion and radioactive decay. Alpha-emitters are strongly retained velocities of alpha-emitters are approximately one thousandth (10-3) that of T. Transport velocities of Cs and Sr are approximately one hundreth (10-2) and one tenth (10-1) that of T respectively. (orig./HP)

275

Effects of Soil Treatments on The Survival of Soil Microorganisms  

OpenAIRE

In biological control studies of plant-parasitic nematodes in field soil improved methods are needed for reducing or eliminating specific soil inhabiting microorganisms. Microwave heating of soil decreases soilborne fungi and bacteria, but not Pasteuria spp. Bacterial and fungal colony forming units were reduced to nondetectable levels in microwaved heated field soft (650 watts) at 5.2% moisture when treated for 6 minutes and 4 minutes, respectively.

Chen, S. Y.; Dickson, D. W.; Mitchell, D. J.

1995-01-01

276

A Study of Effective Soil Compaction Control of Granular Soils  

OpenAIRE

Although it is known that impact compaction tests are not appropriate for granular soils, these tests continue to be widely used. Excessive settlements frequently occur in granular soils where specified field compaction is based on Standard Proctor (ASTM D 698; AASHTO T 99) maximum dry unit weights. A laboratory test program evaluated alternative test methods for granular soil compaction control and showed that a Vibrating Hammer method (similar to British Standard BS 1377:1975, Test 14) has ...

Drnevich, Vincent P.; Evans, Aaron C.; Prochaska, Adam Buser

2007-01-01

277

Soil vapor extraction of JP-4 jet fuel contaminated soils  

International Nuclear Information System (INIS)

This paper presents findings and lessons learned from the investigation, pilot, design, and remedial action phases of a soil vapor extraction (SVE) project. Soil vapor extraction was performed on JP-4 jet fuel contaminated soils at two fire training pits at Luke AFB, Arizona. The site was used for fire training exercises on a quarterly basis from 1973 to as late as 1990. Petroleum wastes were originally used for fire training exercised but this practice was discontinued during 1973. Five soil borings were drilled and sampled in each of the two fire training pits during the investigations

278

Soil Properties Database of Spanish Soils Volume I.-Galicia  

International Nuclear Information System (INIS)

The soil vulnerability determines the sensitivity of the soil after an accidental radioactive contamination due to Cs-13 7 and Sr-90. The Department de Impacto Ambiental de la Energia of CIEMAT is carrying out an assessment of the radiological vulnerability of the different Spanish soils found on the Iberian Peninsula. This requires the knowledge of the soil properties for the various types of existing soils. In order to achieve this aim. a bibliographical compilation of soil profiles has been made to characterize the different soil types and create a database of their properties. Depending on the year of publication and the type of documentary)' source, the information compiled from the available bibliography is very heterogeneous. Therefore, an important effort has been made to normalize and process the information prior to its incorporation to the database. This volume presents the criteria applied to normalize and process the data as well as the soil properties of the various soil types belonging to the Comunidad Autonoma de Galicia

279

Soil Properties Database of Spanish Soils. Volume XIV.- Cataluna  

International Nuclear Information System (INIS)

The soil vulnerability determines the sensitivity of the soil after an accidental radioactive contamination due to Cs-137 and Sr-90. The Departamento de Impacto Ambiental de la Energia of CIEMAT is carrying out an assessment of the radiological vulnerability of the different Spanish soils found on the Iberian Peninsula. This requires the knowledge of the soil properties for the various types of existing soils. In order to achieve this aim, a bibliographical compilation of soil profiles has been made to characterize the different soil types and create a database of their properties. Depending on the year of publication and the type of documentary source, the information compiled from the available bibliography is very heterogeneous. Therefore, an important effort has been made to normalize and process the information prior to its incorporation to the database. This volume presents the criteria applied to normalize and process the data as well as the soil properties of the various soil types belonging to the Comunidad Autonoma of Cataluna. (Author) 57 refs

280

Soil Properties Database of Spanish Soils. Volume V.- Madrid  

International Nuclear Information System (INIS)

The soil vulnerability determines the sensitivity of the soil after an accidental radioactive contamination due to Cs-137 and Sr-90. The Departamento de Impacto Ambiental de la Energia of CIEMAT is carrying out an assessment of the radiological vulnerability of the different Spanish soils found on the Iberian Peninsula. This requires the knowledge of the soil properties for the various types of existing soils. In order to achieve this aim, a bibliographical compilation of soil profiles has been made to characterize the different soil types and create a database of their properties. Depending on the year of publication and the type of documentary source, the information compiled from the available bibliography is very heterogeneous. Therefore, an important effort has been made to normalize and process the information prior to its incorporation to the database. This volume presents the criteria applied to normalize and process the data as well as the soil properties of the various soil types belonging to the Comunidad Autonoma de Madrid. (Author) 39 refs

281

Copper activity in soil solutions of calcareous soils  

International Nuclear Information System (INIS)

Copper partitioning was studied in seven calcareous soils at moisture content corresponding to 1.2 times the field moisture content (soil water potential 7.84 J kg-1). Copper retention was accompanied by the release in soil solution of Ca2+, Mg2+, Na+, and H+, and the total amount of these cations released was 0.8 to 1.09 times the amount of Cu sorbed (molc:molc). The relationships between Cu activity and pH, and the balance of cations in soils correspond with the surface precipitation of CuCO3 as the main mechanism of Cu retention. The values of ion activity product of surface precipitate were close for all studied soils with the average log(IAPCuCO3) = -15.51. The relationship between copper activity in soil solutions and soil properties is well fit by a regression relating pCu (-log copper ion activity) with soil ph, total Cu, and carbonate content. - Copper activity in contaminated calcareous soils is controlled by surface precipitated CuCO3 with log ion activity product of -15.51

282

Quantifying Shrink Swell Capacity of Soil Using Soil Moisture Isotherms  

Science.gov (United States)

Vertisols, soils instinctively known for their expansive clays that cause them to have a high shrink swell potential, cover 2.4% of the earths ice-free land. In the United States these expansive soils can cause upwards of 6 billion in damages to pavements, foundations, and utility lines annually (Brady & Weil, 2010). Because of this, it is especially important that a soils ability to shrink and swell is well characterized when making engineering decisions. One traditional method for measuring a soil's expansive potential, the Coefficient of Linear Extensibility (COLE), can take weeks to months to complete (Grossman et al., 1968; Schafer and Singer, 1976b). Use of soil moisture isotherms, or the Soil Moisture Characteristic Curve (SMCC), in recent research has shown that the slope of the SMCC is related to a soils swelling potential (McKeen, 1992). The goal of this research is to evaluate the robustness of the relationship between the SMCC and COLE for a set of well-characterized test soils with COLE ranging from 0 to 0.176. If expansive potential can be reliably predicted from the SMCC, then data from recently developed automatic soil moisture isotherm generators could be used to characterize expansive potential with a fraction of the time and effort necessary for traditional techniques.

Rivera, L. D.; Cobos, D. R.; Campbell, C. S.; Morgan, C.

2013-12-01

283

Soil Properties Database of Spanish Soils. Volume XV.- Aragon  

International Nuclear Information System (INIS)

The soil vulnerability determines the sensitivity of the soil after an accidental radioactive contamination due to Cs-137 and Sr-90. The Departamento de Impacto Ambiental de la Energia of CIEMAT is carrying out an assessment of the radiological vulnerability of the different Spanish soils found on the Iberian Peninsula. This requires the knowledge of the soil properties for the various types of existing soils. In order to achieve this aim, a bibliographical compilation of soil profiles has been made to characterize the different soil types and create a database of their properties. Depending on the year of publication and the type of documentary source, the information compiled from the available bibliography is very heterogeneous. Therefore, an important effort has been made to normalize and process the information prior to its incorporation to the database. This volume presents the criteria applied to normalize and process the data as well as the soil properties of the various soil types belonging to the Comunidad Autonoma of Aragon. (Author) 47 refs

284

Geochemical Modeling of Soils: A Soil-Component Approach  

Science.gov (United States)

Quantitative modeling of pedological processes begins by placing measured soil properties within a framework that allows the identification and testing of geochemical and biological mechanisms. For example, mass-balance interpretations of pedogenesis describe gains and losses of chemical elements in a manner that can implicate specific mineral reactions and biological processes. Soil-component modeling is an extension of the mass-balance interpretation of pedogenesis that describes observed gains and losses in chemical elements, ion-exchange capacity, and soil volume with hypothesized sets of soil components such as minerals and soil organic matter. These models are calculated using mole-balance equations for mineral components, associated equations for ion-exchange capacities and volumes of minerals and soil organic matter, and equations that account for the uncertainties of all analytical data. The GRex computer program was written to evaluate these relations and identify combinations of minerals and organic matter that can simultaneously account for the observed chemical and physical properties of a single soil or net-change in properties between two related soils. The power of this approach is that many alternative scenarios of mineral and organic matter assemblages can be quickly defined that may provide insight into the geochemical mechanisms of pedogenesis, or suggest additional field and laboratory work. Examples of this modeling method, as applied to data on soils from sites along a marine terrace chronosequence in Oregon and a basalt climosequence on the island of Hawaii, will be shown.

Lee, L.

2004-12-01

285

Elementary GLOBE: Getting to Know Soil  

Science.gov (United States)

A learning activity for the Scoop on Soils book in the Elementary GLOBE Series. Each student will make predictions about the properties of various soil samples. Then they will examine several types of soils and record their observations. Next, they will learn about soil profiles and horizons by both examining a soil sample in a jar and by creating a soil profile flip chart. The purpose of the activity is to provide the opportunity for students to ask questions and make observations about soil and introduce students to the properties of soil and to the concept of soil profiles and horizons. After completing this activity, students will know about soil's different properties and about soil profiles. Students will know that soils have different properties including texture, color, and size. They will know that soil forms layers based on these properties.

2008-12-01

286

ASPECTS REGARDING THE METHODS OF SOIL AERATION  

Directory of Open Access Journals (Sweden)

Full Text Available Aspects regarding the methods of soil aeration. Soil aeration is a process to be carried out continuously the gas exchange between soil and atmosphere. The process is done mainly by the movement of water inside and outside him. There are three major gases in the soil (nitrogen,oxygen and carbon dioxide. Soil air composition differs from that of air by higher CO2 content (0,3 to 0,5%. The air in the soil is very important for the dynamics of soil. Soil aeration is accomplished through mass flow and diffusion. In this paper the authors present these methods of soil aeration

A. UNGURA?U

2011-03-01

287

Stochastic Modeling of Soil Salinity  

CERN Document Server

A minimalist stochastic model of primary soil salinity is proposed, in which the rate of soil salinization is determined by the balance between dry and wet salt deposition and the intermittent leaching events caused by rainfall events. The long term probability density functions of salt mass and concentration are found by reducing the coupled soil moisture and salt mass balance equation to a single stochastic differential equation driven by multiplicative Poisson noise. The novel analytical solutions provide insight on the interplay of the main soil, plant and climate parameters responsible for long-term soil salinization. In particular, they show the existence of two distinct regimes, one where the mean salt mass remains nearly constant (or decreases) with increasing rainfall frequency, and another where mean salt content increases markedly with increasing rainfall frequency. As a result, relatively small reductions of rainfall in drier climates may entail dramatic shifts in long-term soil salinization trend...

Suweis, S; Van der Zee, S E A T M; Daly, E; Maritan, A; Porporato, A; 10.1029/2010GL042495

2012-01-01

288

Modelling soil organic carbon concentration of mineral soils in arable lands using legacy soil data  

DEFF Research Database (Denmark)

Soil organic carbon (SOC) concentration is an essential factor in biomass production and soil functioning. SOC concentration values are often obtained by prediction but the prediction accuracy depends much on the method used. Currently, there is a lack of evidence in the soil science literature as to the advantages and shortcomings of the different commonly used prediction methods. Therefore, we compared and evaluated the merits of the median approach, analysis of covariance, mixed models and random forests in the context of prediction of SOC concentrations of mineral soils under arable management in the A-horizon. Three soil properties were used in all of the developed models: soil type, physical clay content (particle size <0.01 mm) and A-horizon thickness. We found that the mixed model predicted SOC concentrations with the smallest mean squared error (0.05%2), suggesting that a mixed-model approach is appropriate if the study design has a hierarchical structure as in our scenario. We used the Estonian National Soil Monitoring data on arable lands to predict SOC concentrations of mineral soils. Subsequently, the model with the best prediction accuracy was applied to the Estonian digital soil map for the case study area of Tartu County where the SOC predictions ranged from 0.6 to 4.8%. Our study indicates that predictions using legacy soil maps can be used in national inventories and for up-scaling estimates of carbon concentrations from county to country scales.

Suuster, E; Ritz, Christian

2012-01-01

289

Dependence of soil respiration on soil temperature and soil moisture in successional forests in Southern China  

Science.gov (United States)

The spatial and temporal variations in soil respiration and its relationship with biophysical factors in forests near the Tropic of Cancer remain highly uncertain. To contribute towards an improvement of actual estimates, soil respiration rates, soil temperature, and soil moisture were measured in three successional subtropical forests at the Dinghushan Nature Reserve (DNR) in southern China from March 2003 to February 2005. The overall objective of the present study was to analyze the temporal variations of soil respiration and its biophysical dependence in these forests. The relationships between biophysical factors and soil respiration rates were compared in successional forests to test the hypothesis that these forests responded similarly to biophysical factors. The seasonality of soil respiration coincided with the seasonal climate pattern, with high respiration rates in the hot humid season (April-September) and with low rates in the cool dry season (October-March). Soil respiration measured at these forests showed a clear increasing trend with the progressive succession. Annual mean (?? SD) soil respiration rate in the DNR forests was (9.0 ?? 4.6) Mg CO2-C/hm2per year, ranging from (6.1 ?? 3.2) Mg CO2-C/hm2per year in early successional forests to (10.7 ?? 4.9) Mg CO2-C/hm2 per year in advanced successional forests. Soil respiration was correlated with both soil temperature and moisture. The T/M model, where the two biophysical variables are driving factors, accounted for 74%-82% of soil respiration variation in DNR forests. Temperature sensitivity decreased along progressive succession stages, suggesting that advanced-successional forests have a good ability to adjust to temperature. In contrast, moisture increased with progressive succession processes. This increase is caused, in part, by abundant respirators in advanced-successional forest, where more soil moisture is needed to maintain their activities. ?? 2006 Institute of Botany, Chinese Academy of Sciences.

Tang, X.-L.; Zhou, G.-Y.; Liu, S.-G.; Zhang, D.-Q.; Liu, S.-Z.; Li, J.; Zhou, C.-Y.

2006-01-01

290

In-situ vitrification of soil  

International Nuclear Information System (INIS)

A method of vitrifying soil at or below a soil surface location. Two or more conductive electrodes are inserted into the soil for heating of the soil mass between them to a temperature above its melting temperature. Materials in the soil, such as buried radioactive waste, can thereby be effectively immobilized. (author)

291

Field Book for Describing and Sampling Soils  

Science.gov (United States)

This field guide is useful for making or reading soil and site descriptions. The major sections address soil profile description, geomorphology, geology, soil taxonomy, soil map symbols, and field sampling strategies. Rock charts and timescales are provided to help with soil identification.

292

Correlation between Soil Test Phosphorus of Kaolinitic and Smectitic Soils with Phosphorus Uptake of Lowland Rice  

OpenAIRE

Correlation between soil test phosphorus (P) and plant-available P parameters were affected by soil properties, such as soil pH, particle-size composition, and mineralogy. The objectives of this research were: (1) to determine P concentration extracted by several soil P test method in kaolinitic and smectitic soil, and (2) to determine correlation between soil P test and soil properties, P fractions, P sorption parameters, and P uptake of lowland rice. The soil P test in kaolinitic and smecti...

Mohammad Masjkur

2009-01-01

293

Role of soil properties in water retention characteristics of main Hungarian soil types  

OpenAIRE

Relationship between easily available soil properties and soil water retention at given matric potentials were analysed on brown forest soils, chernozems and meadow soils of Hungarian Detailed Soil Hydrophysical Database (Hungarian acronym: MARTHA). We studied the influence of soil properties displayed on the 1:10000 scale Hungarian soil maps on soil water retention at -0.1, -33, -1500 and -150000 kPa. Continuous (particle size distribution, organic matter content, calcium carbonate content a...

Brigitta Toth; Andras Mako; Gergely ToTH

2014-01-01

294

Soil classes and acceleration response  

International Nuclear Information System (INIS)

It could not enough for determination of only geotechnical properties (soil classification, soil type, bearing capacity etc.) in order to define assessment of areas being settle in terms of suitability of settlement or how settled area is affected from natural disaster and to get necessary precautions. Damages on the engineering structure in the region posses an earthquake hazard are affected one or more site condition from source point to soil of engineering structure

295

Stochastic Models of Soil Denitrification  

OpenAIRE

Soil denitrification is a highly variable process that appears to be lognormally distributed. This variability is manifested by large sample coefficients of variation for replicate estimates of soil core denitrification rates. Deterministic models for soil denitrification have been proposed in the past, but none of these models predicts the approximate lognormality exhibited by natural denitrification rate estimates. In this study, probabilistic (stochastic) models were developed to understan...

Parkin, T. B.; Robinson, J. A.

1989-01-01

296

Indicators for Monitoring Soil Biodiversity  

DEFF Research Database (Denmark)

The European Union (EU) soil policy is described in general terms in the EU Soil Strategy (EC 2006a) and the legally binding elements of the policy are proposed in the draft Soil Framework Directive (SFD; EC 2006b). In these documents, eight main threats to soil were identified by the EU Commission. The EU FP6 project ENVASSO (Environmental Assessment of Soil for Monitoring) had the aim to design a single, integrated and operational set of EU-wide criteria and indicators to provide the basis for a harmonised comprehensive soil and land information system for monitoring in Europe. Here, a proposal is made for a set of suitable indicators for monitoring the decline in soil biodiversity (Bispo et al. 2007). These indicators were selected both from a literature review and an inventory of national monitoring programmes. Decline in soil biodiversity was defined as the reduction of forms of life living in soils (both in terms of quantity and variety) and of related functions, causing a deterioration of one or more soil functions or ecosystem services. Whereas literature review allows the identification of about 100 possible indicators, the inventory of existing monitoring networks shows that few indicators are actually measured. For monitoring application it was considered in ENVASSO that only three key indicators per soil stress were practical. For indicating biodiversity decline it was difficult to arrive at a small set of indicators due to the complexity of soil biota and functions. Therefore, three stringent criteria were applied: an indicator should 1) have a standardized sampling and/or measuring methodology; 2) be complementary to other indicators; and 3) be easy to interpret at both scientific and policy levels.

Bispo, A.; Cluzeau, D.

2009-01-01

297

HUMUS SUBSTANCES AND SOIL FERTILITY  

OpenAIRE

The humus substances play an important role in obtaining high yields and stable over time. He is permanently double process: the humus improvement of organic material reaching the soil and the mineralization of components at different stages of humus improving, The results of this process is influenced by soil type, climate, irrigation, fertilization. The beneficial effect of humus substances on plant growth may be related to indirect effects (fertilization efficiency or reduce soil compacti...

Neagu, Cecilia Violeta; Oprea, Georgeta

2012-01-01

298

Soil fauna and global change  

OpenAIRE

To examine possible effects of global change on soil fauna abundance and diversity, two long-term field experiments in Norway spruce stands in Sweden were studied. Soil fauna (Oribatida, Mesostigmata, Collembola, predatory macroarthropods and Enchytraeidae) were sampled in plots experimentally simulating altered precipitation patterns and increased soil temperature. Six years of summer drought caused large decreases in abundance in all faunal groups and a reduction in species diversity of Ori...

Lindberg, Niklas

2003-01-01

299

Biogeochemical processes in frozen soils  

OpenAIRE

High latitude ecosystems are important for global carbon (C) balances and are among the most sensitive ecosystems to climate change. Microbial CO2 production in soil is known to proceed at temperatures < 0C in these regions and winter CO2 emissions can significantly affect annual C balances. However, the low-temperature processes involved were poorly understood. In frozen soils, the microbial activity must be confined to small pools of liquid water present in the bulk soil. Therefore, in la...

Harrysson Drotz, Stina

2010-01-01

300

Anlise espacial dos fatores da equao universal de perda de solo em rea de nascentes / Spatial analysis of universal soil loss equation factors of a watershed area relief  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese O objetivo deste trabalho foi avaliar a perda de solo de rea de nascentes da Microbacia do Crrego do Tijuco, SP. Foi utilizada a anlise espacial dos fatores da equao universal da perda de solo (EUPS), em integrao com anlise de componentes principais e geoestatstica. A perda de solo mdia, e [...] stimada para a rea, foi de 118,5 Mg ha?1 por ano, considerada alta. Prximo zona urbana, houve alta interao dos fatores erosividade da chuva e prticas conservacionistas, o que evidencia grande perda de solo, em razo da concentrao da gua proveniente da camada impermeabilizada urbana, com alta velocidade de escoamento. Nos divisores de guas, a atuao da erodibilidade foi proeminente, em contraste com o fator topogrfico. Foram observadas reas com atuao conjunta destes fatores, inclusive em locais de inclinao suave, porm com alto potencial natural de eroso. A interao das anlises multivariadas e geoestatstica permite a estratificao da rea, identifica locais com propriedades especficas quanto perda de solo, e espacializa os fatores do processo erosivo e suas interaes ao longo do relevo. Abstract in english The objective of this work was to evaluate the soil loss of an area of springs in the Microbacia do Crrego do Tijuco, SP, Brazil. Spatial analysis of the universal soil loss equation (USLE) factors, in integrated with principal component analysis and geostatistics, was used. The average soil loss e [...] stimated for the area was 118.5 Mg ha?1 per year, which is considered high. Near the urban zone, there was a high interaction of rainfall erosivity and conservation practices, which shows a high?soil loss, due to the concentration of water from impervious urban layer with a high?flow velocity. In the water partings, the performance of erodibility was prominent, in contrast to the topographic factor. Areas were observed with joint action of these factors, including sites with gentle slope, but with a high, natural potential of erosion. The interaction of multivariate and geostatistic analyses allows the area stratification, identifies locations with specific properties as to soil loss, and spatialises the erosion factors and their interactions along the landscape.

Daniela Popim, Miqueloni; Clia Regina Paes, Bueno; Antonio Sergio, Ferraudo.

1358-13-01

301

Imidacloprid and pyrimethanil soil sorption  

OpenAIRE

The sorption of imidacloprid and pyrimethanil was measured in different soils of southern Europe. Pyrimethanil sorption (Kf=1.2-4.60) was higher than that of imidacloprid (Kf=0.31-1.99). Sorption was influenced by organic carbon content and increased with time when the soil was incubated at 25 $^\\circ$C and 35% soil water content. Over a period of 14 days, the distribution coefficient between solid (soil) and solution phases increased by orders of magnitude of 2 and 4 respectively, for imidac...

Capri, Ettore; Camisa, M.; Flores-ce?spedes, F.; Glass, C.; Gonzalez-pradas, E.; Trevisan, Marco

2001-01-01

302

Soil Moisture Monitoring for Agriculture  

International Science & Technology Center (ISTC)

Elaboration of a Modern Technology for Operational Agrometeorological Soil Moisture Monitoring Spring Wheat, Yield and Disease Damage Forecasting and Recommendations for Plant Protection on the Kazakhstan Territory

303

The Systems Mapping of Soils  

Science.gov (United States)

Soil, together with rocks, waters, air, and living organisms, is one of the natural elements, which make up landscapes. At the same time soil is a unique (derivative) natural element because only it originates from the interaction of all the other (basic) natural elements. Reasoning from this fact, soil maps must be unique too - fundamentally different from geological, geomorphological, natural vegetation, and other thematic maps of the basic natural elements. It is suggested creating conceptually new soil maps, namely the systems soil maps, which are derived from the systems landscape maps. Legends of such maps are based on hierarchical classification of natural landscapes-systems. The last-mentioned are regarded as elementary structural units of the Earth's landscape envelope comprised of interacting landscape elements. The landscapes-systems step by step are divided into divisions and subdivisions of different hierarchical levels unless reaching separate and isolated landscapes-systems, which can not be divided further because of their homogeneity. Criteria used to differentiate between landscapes-systems include the most prominent properties of natural landscape elements, for instance: sequence of the elements, range of altitudes and slopes, zonal vegetation types associated with effective heat sum and precipitation ratio, the main genetic soil horizons, genetic types and forms of relief, lithology of parent materials, depth of humus horizons, chemical composition of ground waters, and so forth. Levels at which criteria of classification are soil properties are named the "soil" one; they are the lowest one in each scale range. The systems soil maps are produced for "soil" levels and show certain soil properties in connection with those properties of the basic natural elements, which cause these soil properties. In GIS environment the systems soil maps are produced automatically from an integrated polygon layer created manually on the basis of expert analysis of the maximum possible quantity of thematic, mainly paper, maps, and texts. The hierarchy of the natural landscapes, as well as hierarchy of the properties of their elements, is displayed with the help of an additional line layer containing information about rank-ordered natural boundaries. Currently, polygon systems maps of Saratov oblast in GIS format and paper systems maps of the Nechernozemnaya Zone of the European Russia have been created. Scale of the main topographic maps, which were used, is 1:1,500,000. The systems soil mapping is regarded as a pathway to development of a global soil data infrastructure and universal soil classification system.

Nikiforova, Alexandra; Fleis, Maria; Borisov, Mickail

2013-04-01

304

Soils and Geomorphology, Third Edition  

Science.gov (United States)

In accepting the Kirk Bryan Award in 1988 from the Quaternary Geology and Geomorphology Division of the Geological Society of America, Pete Birkeland commented that he was passing the soil geomorphology baton on to the next generation. Fortunately for us, the hand-off is still incomplete, as evidenced by the publication of a new third edition of his award winning book, Soils and Geomorphology.Birkeland's book is notable for being a survey of soil science from a geological perspective. Thus the focus is on field aspects of soil science, particularly on pedology the study of soil genesis. The book is studded with field examples, drawn from the literature and from his own nearly forty years of fieldwork in the American West and around the world. The issues he addresses are often geological in nature: dating landforms, reading past climates from information in soils, and using soils as stratigraphic markers. His philosophy is that the principles of soil genesis must be learned and understood before one can interpret the geological record in soils.

Anderson, Suzanne Prestrud

305

Soil fauna community in the black soil of northeast China under different conservation tillage systems  

Science.gov (United States)

Soil fauna is an important component in soil ecosystem. Through the soil moisture changes, soil environment is changed under different tillage systems, and then the population of soil fauna also is changed. This study tested whether conservation tillage or conventional tillage (CT) of black soil fie...

306

Soil fauna and soil functions: a jigsaw puzzle  

Directory of Open Access Journals (Sweden)

Full Text Available Terrestrial ecologists and soil modelers have traditionally portrayed the inhabitants of soil as a black box labeled as "soil fauna" or "decomposers or detritivores assuming that they just merely recycle the deposited dead plant material. Soil is one of the most diverse habitats on Earth and contains one of the most diverse assemblages of living organisms; however, the opacity of this world has severely limited our understanding of their functional contributions to soil processes and to ecosystem resilience. Traditional taxonomy, based on morphological and anatomical aspects, is becoming replaced by rapid processing molecular techniques (e.g. with marker gene-based approaches. However, this may be impracticable in many ecological studies and consequently, the majority of the current knowledge, still contributes little to our understanding of their role in ecosystem functioning. Over the years, different workers have produced several functional classifications based on the body width, feeding regime, certain behavioral and reproductive aspects and ecological niches of soil organisms. Unfortunately, the information available is severely restricted to major groups. A better physiological and metabolic understanding of when and how a complex community of soil organisms access nutrients, alter their environment and in turn, affect soil processes, will allow a more realistic quantitative evaluation of their ecological roles in the biogeochemical cycles. Here, I review the applicability of the available approaches, highlight future research challenges and propose a dynamic conceptual framework that could improve our ability to solve this functional puzzle.

MariaJ.I.Briones

2014-04-01

307

New perspectives on the soil erosion-soil quality relationship  

International Nuclear Information System (INIS)

The redistribution of soil has a profound impact on its quality (defined as its ability to function within its ecosystem and within adjacent ecosystems) and ultimately on its productivity for crop growth. The application of 137Cs-redistribution techniques to the study of erosion has yielded major new insights into the soil erosion-soil quality relationship. In highly mechanized agricultural systems, tillage erosion can be the dominant cause of soil redistribution; in other agroecosystems, wind and water erosion dominate. Each causal factor results in characteristic landscape-scale patterns of redistribution. In landscapes dominated by tillage redistribution, highest losses occur in shoulder positions (those with convex downslope curvatures); in water-erosion-dominated landscapes, highest losses occur where slope gradient and length are at a maximum. Major impacts occur through the loss of organically-enriched surface material and through the incorporation of possibly yield-limiting subsoils into the rooting zone of the soil column. The potential impact of surface soil losses and concomitant subsoil incorporation on productivity may be assessed by examining the pedological nature of the affected soils and their position in the landscape. The development of sound conservation policies requires that the soil erosion-quality relationship be rigorously examined in the full range of pedogenic environments, and future applications of the 137Cs technique hold considerable promise for providing this comprehensive global database. (author)

308

Pedotransfer functions estimating soil hydraulic properties using different soil parameters  

DEFF Research Database (Denmark)

Estimates of soil hydraulic properties using pedotransfer functions (PTF) are useful in many studies such as hydrochemical modelling and soil mapping. The objective of this study was to calibrate and test parametric PTFs that predict soil water retention and unsaturated hydraulic conductivity parameters. The PTFs are based on neural networks and the Bootstrap method using different sets of predictors and predict the van Genuchten/Mualem parameters. A Danish soil data set (152 horizons) dominated by sandy and sandy loamy soils was used in the development of PTFs to predict the Mualem hydraulic conductivity parameters. A larger data set (1618 horizons) with a broader textural range was used in the development of PTFs to predict the van Genuchten parameters. The PTFs using either three or seven textural classes combined with soil organic mater and bulk density gave the most reliable predictions of the hydraulic properties of the studied soils. We found that introducing measured water content as a predictor generally gave lower errors for water retention predictions and higher errors for conductivity predictions. The best of the developed PTFs for predicting hydraulic conductivity was tested against PTFs from the literature using a subdata set of the data used in the calibration. The test showed that the developed PTFs gave better predictions (lower errors) than the PTFs from the literature. This is not surprising since the developed PTFs are based mainly on hydraulic conductivity data near saturation and sandier soils than the PTFs from the literature.

Brgesen, Christen Duus; Iversen, Bo Vangs

2008-01-01

309

Soil Carbon Changes Influenced by Soil Management and Calculation Method  

OpenAIRE

Throughout the years, many studies have evaluated changes in soil organic carbon (SOC) mass on a fixed-depth (FD) basis without considering changes in soil mass caused by changing bulk density (?b). This study evaluates the temporal changes in SOC caused by two factors: 1) changing SOC concentration; and...

Mikha, Maysoon M.; Benjamin, Joseph G.; Halvorson, Ardell D.; Nielsen, David C.

2013-01-01

310

Soil carbon sequestration estimated with the soil conditioning index  

Science.gov (United States)

Rapid and reliable assessments of the potential of different agricultural management systems to sequester soil organic carbon are needed to promote conservation and help mitigate greenhouse gas emissions. The soil conditioning index (SCI) is a relatively simple model to parameterize and is currentl...

311

Desert soil collection at the JPL soil science laboratory  

Science.gov (United States)

Collection contains desert soils and other geologic materials collected from sites in the United States and foreign countries. Soils are useful for test purposes in research related to extraterrestrial life detection, sampling, harsh environmental studies, and determining suitable areas for training astronauts for lunar exploration.

Blank, G. B.; Cameron, R. E.

1969-01-01

312

Online Soil Science Lesson 3: Soil Forming Factors  

Science.gov (United States)

This lesson explores the five major factors of soil formation, namely: 1) climate; 2) organisms; 3) time; 4) topography; and 5) parent material and their influence in forming soil. The distinction between active and passive factors, moisture and temperature regimes, organism and topographic influen...

313

Soil Chapter-Soils as Sponges: How Much Water does Soil Hold?  

Science.gov (United States)

Students determine the moisture content of a sponge after squeezing the water out of the sponge, and allowing water to evaporate from the sponge. Students also measure the amount of water that has evaporated from the soil samples. This learning resource is part of the Soils chapter of the GLOBE Teacher's Guide, and is supported by the GLOBE soils protocols. GLOBE (Global Learning and Observation to Benefit the Environment) is a worldwide, hands-on, K-12 school-based science education program.

314

Assessment of Soil Intrinsic Properties Effects on Soil Structural Stability of Some Soils in Hamadan Province  

OpenAIRE

The effects of soil intrinsic properties on soil structural stability were evaluated. Soil samples (33 series) with wide ranges of properties and structural stability were collected from Hamadan province. Two structural stability indices were used: mean weight diameter (MWD) using Yoder method and De Leenheer-De Boodt index (DDI). Wetting pre-treatments (fast wetting to saturation and slow wetting to a matric suction of 30 kPa) were applied before wetting. Linear and multiple regression relat...

Nikpur, M.; Mahboubi, A. A.; Mosaddeghi, M. R.; Safadoust, A.

2012-01-01

315

Stochastic Modeling of Soil Salinity  

Science.gov (United States)

Large areas of cultivated land worldwide are affected by soil salinity. Estimates report that 10% of arable land in over 100 countries, and nine million km2 are salt affected, especially in arid and semi-arid regions. High salinity causes both ion specific and osmotic stress effects, with important consequences for plant production and quality. Salt accumulation in the root zone may be due to natural factors (primary salinization) or due to irrigation (secondary salinization). Simple (e.g., vertically averaged over the soil depth) coupled soil moisture and salt balance equations have been used in the past. Despite their approximations, these models have the advantage of parsimony, thus allowing a direct analysis of the interplay of the main processes. They also provide the ideal starting point to include external, random hydro-climatic fluctuations in the analysis of long-term salinization trends. We propose a minimalist stochastic model of primary soil salinity, in which the rate of soil salinization is determined by the balance between dry and wet salt deposition and the intermittent leaching events caused by rainfall events. The long term probability density functions of salt mass and concentration are found by reducing the coupled soil moisture and salt mass balance equation to a stochastic differential equation driven by multiplicative Poisson noise. The novel analytical solutions provide insight on the interplay of the main soil, plant and climate parameters responsible for long-term soil salinization. In fact, soil salinity statistics are obtained as a function of climate, soil and vegetation parameters. These, in turn, can be combined with soil moisture statistics to obtain a full characterization of soil salt concentrations and the ensuing risk of primary salinization. In particular, the solutions show the existence of two quite distinct regimes, the first one where the mean salt mass remains nearly constant with increasing rainfall frequency, and the second one where mean salt content increases markedly with increasing rainfall frequency. As a result, relatively small reductions of rainfall in drier climates may entail dramatic shifts in long-term soil salinization trends, with significant consequences e.g. for climate change impacts on rain-fed agriculture. The analytical nature of the solution allows direct estimation of the impact of changes in the climatic drivers on soil salinity and makes it suitable for computations of salinity risk at the global scale as a function of simple parameters. Moreover it facilitates their coupling with other models of long-term soil-plant biogeochemistry.

Suweis, Samir; Rinaldo, Andrea; van der Zee, Sjoerd E. A. T. M.; Maritan, Amos; Porporato, Amilcare

2010-05-01

316

Stool Soiling and Constipation in Children  

Science.gov (United States)

MENU Return to Web version Stool Soiling and Constipation in Children Stool Soiling and Constipation in Children What are the causes of stool ... toilet trained accidentally leak feces into their underwear. Constipation is often the cause of stool soiling. Usually, ...

317

Soil management practices for sustainable crop production  

International Nuclear Information System (INIS)

In a sustainable system, the soil is viewed as a fragile and living medium that must be protected and nurtured to ensure its long-term productivity and stability. However, due to high demand for food brought about by high population as well as the decline in agricultural lands, the soil is being exploited beyond its limit thus, leading to poor or sick soils. Sound soil management practices in the Philippines is being reviewed. The technologies, including the advantages and disadvantages are hereby presented. This includes proper cropping systems, fertilizer program, soil erosion control and correcting soil acidity. Sound soil management practices which conserve organic matter for long-term sustainability includes addition of compost, maintaining soil cover, increasing aggregates stability, soil tilt and diversity of soil microbial life. A healthy soil is a key component to sustainability as a health soil produce healthy crop plants and have optimum vigor or less susceptible to pests. (author)

318

Soil sampling for environmental contaminants  

International Nuclear Information System (INIS)

The Consultants Meeting on Sampling Strategies, Sampling and Storage of Soil for Environmental Monitoring of Contaminants was organized by the International Atomic Energy Agency to evaluate methods for soil sampling in radionuclide monitoring and heavy metal surveys for identification of punctual contamination (hot particles) in large area surveys and screening experiments. A group of experts was invited by the IAEA to discuss and recommend methods for representative soil sampling for different kinds of environmental issues. The ultimate sinks for all kinds of contaminants dispersed within the natural environment through human activities are sediment and soil. Soil is a particularly difficult matrix for environmental pollution studies as it is generally composed of a multitude of geological and biological materials resulting from weathering and degradation, including particles of different sizes with varying surface and chemical properties. There are so many different soil types categorized according to their content of biological matter, from sandy soils to loam and peat soils, which make analytical characterization even more complicated. Soil sampling for environmental monitoring of pollutants, therefore, is still a matter of debate in the community of soil, environmental and analytical sciences. The scope of the consultants meeting included evaluating existing techniques with regard to their practicability, reliability and applicability to different purposes, developing strategies of representative soil sampling for cases not yet considered by current techniques and recommending validated techniques applicable to laboratories in developing Member States. This TECDOC includes a critical survey of existing approaches and their feasibility to be applied in developing countries. The report is valuable for radioanalytical laboratories in Member States. It would assist them in quality control and accreditation process

319

The interdisciplinary nature of SOIL  

Science.gov (United States)

The holistic study of soils requires an interdisciplinary approach involving biologists, chemists, geologists, and physicists, amongst others, something that has been true from the earliest days of the field. In more recent years this list has grown to include anthropologists, economists, engineers, medical professionals, military professionals, sociologists, and even artists. This approach has been strengthened and reinforced as current research continues to use experts trained in both soil science and related fields and by the wide array of issues impacting the world that require an in-depth understanding of soils. Of fundamental importance amongst these issues are biodiversity, biofuels/energy security, climate change, ecosystem services, food security, human health, land degradation, and water security, each representing a critical challenge for research. In order to establish a benchmark for the type of research that we seek to publish in each issue of SOIL, we have outlined the interdisciplinary nature of soil science research we are looking for. This includes a focus on the myriad ways soil science can be used to expand investigation into a more holistic and therefore richer approach to soil research. In addition, a selection of invited review papers are published in this first issue of SOIL that address the study of soils and the ways in which soil investigations are essential to other related fields. We hope that both this editorial and the papers in the first issue will serve as examples of the kinds of topics we would like to see published in SOIL and will stimulate excitement among our readers and authors to participate in this new venture.

Brevik, E. C.; Cerd, A.; Mataix-Solera, J.; Pereg, L.; Quinton, J. N.; Six, J.; Van Oost, K.

2015-01-01

320

Anthropogenic effects on soil micromycetes  

Directory of Open Access Journals (Sweden)

Full Text Available This paper is a synthesis of long-term investigations based on the effect of different authropogenic pollutants (mineral and organic fertilizers, heavy metals, contaminated irrigation water, nitrification inhibitor and detergents on the dynamics of soil fungi number. The investigations were performed at the Microbiology Department and trial fields of the Faculty of Agronomy in ?a?ak on smonitza and alluvium soils in field and under greenhouse conditions. Maize, wheat, barley and red clover were used as test plants in these studies. The quantitative composition of the fungi in the soils investigated was determined by the ?apek selective agar dilution method. The study results show that the number of soil fungi was dependent on the type and rate of agrochemicals used, on the growing season, and the soil zone the samples were taken from for the analysis. Lower nitrogen fertiliser rates (80 and 120 kg x ha-1 and organic fertilizers stimulated the development of soil fungi, unlike the rate of 150 kg x ha-1. Heavy metals, mercury and cadmium in particular, as well as high rates of the N-serve nitrification inhibitor, inhibited the development of this group of soil microorganisms. Generally, the adverse effect of contaminated irrigation water on the soil fungi was recorded in both soil types, and particularly in the smonitza under red clover. Low detergent (Meril concentrations did not have any significant effect on this group of microorganisms. In this respect, it can be concluded that the soil fungi number dynamics can be used in monitoring soils polluted by different toxinogenic substances.

?uki? Dragutin A.

2007-01-01

321

Soil fungi as indicators of pesticide soil pollution  

Directory of Open Access Journals (Sweden)

Full Text Available Soil fungi, with their pronounced enzymic activity and high osmotic potential, represent a significant indicator of negative effects of different pesticides on the agroecosystem as a whole. In that respect, a trial was set up on the alluvium soil type with the aim to investigate the effect of different herbicides (Simazine, Napropamid, Paraquat, fungicides (Captan and Mancozeb and insecticides (Fenitrothion and Dimethoate on a number of soil fungi under apple trees. The number of soil fungi was determined during four growing seasons by an indirect method of dilution addition on the Czapek agar. The study results indicate that the fungi belong to the group of microorganisms that, after an initial sensible response to the presence of pesticides in the soil, very rapidly establish normal metabolism enabling them even to increase their number. The fungicides and insecticides applied were found to be particularly effective in that respect.

Mandi? Leka

2005-01-01

322

Soil properties related to 60Co bioavailability in tropical soils  

International Nuclear Information System (INIS)

This work presents the results of field experiments to obtain soil to plants Transfer factor (TF) for 60Co in reference plants cultivated in Ferralsol, Acrisol and Nitisol. These soils represent the majority of Brazilian agricultural area. Values of TF varied from 0.001 to 0.05 for corn and from 0.001 to 0.81 for cabbage. Results of 60Co TF were discussed in relation to the physical and chemical properties of the soils and 60Co geochemical partition. The sequential chemical extraction showed that more than 40% of the 60Co present in the soils are associated to manganese oxides. These results will provide regional values for parameters used in the environmental radiological modeling aiming to optimize the planning of emergency interventions or the waste management related to tropical soils. (author)

323

Thermal stability of soils and detectability of intrinsic soil features  

Science.gov (United States)

Soils are products of long term pedogenesis in ecosystems. They are characterized by a complex network of interactions between organic and inorganic constituents, which influence soil properties and functions. However, the interrelations cannot easily be determined. Our search for unifying principles of soil formation focuses on water binding. This approach was derived from water-dependent soil formation. It considers the importance of water binding in theories about the origin of genes, in the structural arrangement and functionality of proteins, and in the co-evolution of organism species and the biosphere during the history of earth. We used thermogravimetry as a primary experimental technique. It allows a simple determi-nation of bound water together with organic and inorganic components in whole soil samples without a special preparation. The primary goal was to search for fingerprinting patterns using dynamics of thermal mass losses (TML) caused by water vaporization from natural soils, as a reference base for soil changes under land use. 301 soil samples were collected in biosphere reserves, national parks and other areas as-sumingly untouched by human activity in Siberia, North and South America, Antarctica, and in several long term agricultural experiments. The results did not support the traditional data evaluation procedures used in classical differ-ential thermogravimetry. For example, peak positions and amplitudes did not provide useful information. In contrast, using thermal mass losses (TML) in prefixed smaller, e.g. 10 C temperature intervals allowed the determination of the content of carbon, clay, nitrogen and carbonates with high accuracy. However, this approach was applicable for soils and neither for soil-like carbon containing mineral substrates without pedogenetic origin, nor for plant residues or soils containing ashes, cinder, or charcoal. Therefore, intrinsic soil regulation processes are discussed as a possible factor causing applicability of thermogravimetry for soil property determination. Despite of the extreme diversity of individual substances in soils, the thermal decay can be predicted with simple mathematical models. For example, the sum of mass losses in the large temperature interval from 100 C to 550 C (known from organic matter determination by ignition mass loss in past) can be predicted using TML in two small temperature intervals: 130 - 140 C and 320 - 330 C. In this case, the coefficient of determination between measured and calculated results reached an R2 above 0.97. Further, we found close autocorrelations between thermal mass losses in different temperature intervals. They refer to interrelations between evaporation of bound water and thermal decay of organo-mineral complexes in soils less affected by human influence. In contrast, deviations from such interrelations were found under extreme environmental conditions and in soils under human use. Those results confirm current knowledge about influence of clay on both water binding and organic matter accumulation during natural soil formation. Therefore, these interrelations between soil components are discussed as intrinsic features of soils which open the opportunity for experimental distinction of natural soils from organic and inorganic materials which do not have pedogenetic origin.

Siewert, Christian; Kucerik, Jiri

2014-05-01

324

Soil invertebrate fauna affect N2 O emissions from soil.  

Science.gov (United States)

Nitrous oxide (N2 O) emissions from soils contribute significantly to global warming. Mitigation of N2 O emissions is severely hampered by a lack of understanding of its main controls. Fluxes can only partly be predicted from soil abiotic factors and microbial analyses - a possible role for soil fauna has until now largely been overlooked. We studied the effect of six groups of soil invertebrate fauna and tested the hypothesis that all of them increase N2 O emissions, although to different extents. We conducted three microcosm experiments with sandy soil and hay residue. Faunal groups included in our experiments were as follows: fungal-feeding nematodes, mites, springtails, potworms, earthworms and isopods. In experiment I, involving all six faunal groups, N2 O emissions declined with earthworms and potworms from 78.4 (control) to 37.0 (earthworms) or 53.5 (potworms) mg N2 O-N m(-2) . In experiment II, with a higher soil-to-hay ratio and mites, springtails and potworms as faunal treatments, N2 O emissions increased with potworms from 51.9 (control) to 123.5 mg N2 O-N m(-2) . Experiment III studied the effect of potworm density; we found that higher densities of potworms accelerated the peak of the N2 O emissions by 5 days (P soil aeration by the soil fauna reduced N2 O emissions in experiment I, whereas in experiment II N2 O emissions were driven by increased nitrogen and carbon availability. In experiment III, higher densities of potworms accelerated nitrogen and carbon availability and N2 O emissions, but did not increase them. Overall, our data show that soil fauna can suppress, increase, delay or accelerate N2 O emissions from soil and should therefore be an integral part of future N2 O studies. PMID:23625707

Kuiper, Imke; de Deyn, Gerlinde B; Thakur, Madhav P; van Groenigen, Jan Willem

2013-09-01

325

A method to detect soil carbon degradation during soil erosion  

Science.gov (United States)

Soil erosion has been discussed intensively but controversial both as a significant source or a significant sink of atmospheric carbon possibly explaining the gap in the global carbon budget. One of the major points of discussion has been whether or not carbon is degraded and mineralized to CO2 during detachment, transport and deposition of soil material. By combining the caesium-137 (137Cs) approach (quantification of erosion rates) with stable carbon isotope signatures (process indicator of mixing versus degradation of carbon pools) we were able to show that degradation of carbon occurs during soil erosion processes at the investigated mountain grasslands in the central Swiss Alps (Urseren Valley, Canton Uri). Transects from upland (erosion source) to wetland soils (erosion sinks) of sites affected by sheet and land slide erosion were sampled. Analysis of 137Cs yielded an input of 2 and 4.6 tha-1 yr-1 of soil material into the wetlands sites. Assuming no degradation of soil organic carbon during detachment and transport, carbon isotope signature of soil organic carbon in the wetlands could only be explained with an assumed 500-600 and 350-400 years of erosion input into the wetlands Laui and Spissen, respectively. The latter is highly unlikely with alpine peat growth rates indicating that the upper horizons might have an age between 7 and 200 years. While we do not conclude from our data that eroded soil organic carbon is generally degraded during detachment and transport, we propose this method to gain more information on process dynamics during soil erosion from oxic upland to anoxic wetland soils, sediments or water bodies.

Alewell, Christine; Conen, Franz; Schaub, Monika

2010-05-01

326

Soil Respiration: Concept and Measurement Methods  

Directory of Open Access Journals (Sweden)

Full Text Available Soil respiration is the main element in the carbon cycle that makes possible for plants carbon plants to return inthe atmosphere. The objective of this work was to present and discuss some aspects of the soil CO2 efflux. We definedherein, some terms associated to the soil respiration concept, we tackled some aspects regarding the influence oftemperature, humidity and soil pH on soil respiration and we presented the principle of soil respiration measurement byusing dynamic closed chamber system.

SANDOR M.

2010-08-01

327

Field scale soil characterization using pedostructural properties  

OpenAIRE

Accurate soil characterization is crucial for understanding soil-water interactions and allow for better on-farm agricultural and environmental management. Current soil characterization methods lack quantitative attributes that integrate the soil mapping units with environmental and agronomical models. In this research we propose a methodology to physically characterize the soil water medium using quantitative parameters. We incorporated the continuously measured soil water potential curve an...

Salahat, Mohammed Ali

2006-01-01

328

Peculiarities of soil covers in fluvioglacial formations  

OpenAIRE

Soils developed in fluvioglacial sediments usually show a high diversity of features both in horizontal cover and vertical soil profile. The old classification of Lithuanian soils was not differentiated by their granulometric composition. The new classification system contains a separate group of sandy soils (Arenosols), but it is a common case that soils of this group can also be assigned to other soil groups. It is most convenient to classify sands by their genesis, granulometric and minera...

Galvydyte?, Daina; Lukauskas, Evaldas; Volungevic?ius, Jonas

2007-01-01

329

Managing soils for long-term productivity  

OpenAIRE

Meeting the goal of long-term agricultural productivity requires that soil degradation be halted and reversed. Soil fertility decline is a key factor in soil degradation and is probably the major cause of declining crop yields. There is evidence that the contribution of declining soil fertility to soil degradation has been underestimated. Sensitivity to soil degradation is implicit in the assessment of the sustainability of land management practices, with wide recognition of the fact that...

Syers, J. K.

1997-01-01

330

Mitigation of phosphorus leaching from agricultural soils  

OpenAIRE

Phosphorus (P) is an essential element in crop production, but P losses from agricultural soils are a major contributor to surface water eutrophication. This thesis examined the effects of chemical soil properties and soil structure, as governed by agricultural management practices, on P leaching from agricultural soils and how this leaching can be reduced. An initial investigation on the effect of plant-available P concentration in the soil (P-AL) on topsoil P leaching from five soils clearl...

Svanba?ck, Annika

2014-01-01

331

Managing soil remediation problems.  

Science.gov (United States)

Soil remediation has only a short history but the problem addressed is a significant one. Cost estimates for the clean-up of contaminated sites in the European Union and the United States are in the order of magnitude of 1,400 billion ECU. Such an enormous operation deserves the best management it can get. Reliable cost estimations per contaminated site are an important prerequisite. This paper addresses the problems related to site-wise estimations.When solving soil remediation problems, we have to deal with a large number of scientific disciplines. Too often solutions are presented from the viewpoint of only one discipline. In order to benefit from the combined disciplinary knowledge and experience, we think that it is necessary to describe the interrelations between these disciplines. This can be realized by developing an adequate model of the desired process which enables to consider and evaluate the essential factors as interdependent components of the total system.The resulting model provides a binding paradigm to the contributing disciplines which will result in improved efficiency and effectivity of the decision and the cost estimation process. In the near future, we will release the "Biosparging and Bioventing Expert Support System", an expert support system for problem owners, consultants and authorities dealing with the design and operation of a biosparging and/or a bioventing system. PMID:24233422

Okx, J P; Hordijk, L; Stein, A

1996-12-01

332

Geotechnical characteristics of residual soils  

Energy Technology Data Exchange (ETDEWEB)

Residual soils are products of chemical weathering and thus their characteristics are dependent upon environmental factors of climate, parent material, topography and drainage, and age. These conditions are optimized in the tropics where well-drained regions produce reddish lateritic soils rich in iron and aluminum sesquioxides and kaolinitic clays. Conversely, poorly drained areas tend towards montmorillonitic expansive black clays. Andosols develop over volcanic ash and rock regions and are rich in allophane (amorphous silica) and metastable halloysite. The geological origins greatly affect the resulting engineering characteristics. Both lateritic soils and andosols are susceptible to property changes upon drying, and exhibit compaction and strength properties not indicative of their classification limits. Both soils have been used successfully in earth dam construction, but attention must be given to seepage control through the weathered rock. Conversely, black soils are unpopular for embankments. Lateritic soils respond to cement stabilization and, in some cases, lime stabilization. Andosols should also respond to lime treatment and cement treatments if proper mixing can be achieved. Black expansive residual soils respond to lime treatment by demonstrating strength gains and decreased expansiveness. Rainfall induced landslides are typical of residual soil deposits.

Townsend, F.C.

1985-01-01

333

Permafrost soils and carbon cycling  

Science.gov (United States)

Knowledge of soils in the permafrost region has advanced immensely in recent decades, despite the remoteness and inaccessibility of most of the region and the sampling limitations posed by the severe environment. These efforts significantly increased estimates of the amount of organic carbon (OC) stored in permafrost-region soils and improved understanding of how pedogenic processes unique to permafrost environments built enormous OC stocks during the Quaternary. This knowledge has also called attention to the importance of permafrost-affected soils to the global C cycle and the potential vulnerability of the region's soil OC stocks to changing climatic conditions. In this review, we briefly introduce the permafrost characteristics, ice structures, and cryopedogenic processes that shape the development of permafrost-affected soils and discuss their effects on soil structures and on organic matter distributions within the soil profile. We then examine the quantity of OC stored in permafrost-region soils, as well as the characteristics, intrinsic decomposability, and potential vulnerability of this OC to permafrost thaw under a warming climate.

Ping, C. L.; Jastrow, J. D.; Jorgenson, M. T.; Michaelson, G. J.; Shur, Y. L.

2014-10-01

334

Strategies for remediating polluted soils  

OpenAIRE

For several years, a group of researchers from several institutions has been evaluating strategies for remediating soils polluted with heavy metals and inorganic compounds (such as salts that separate into their anions and metals). Both these substances may be taken up as mineral nutrients of the plants growing in these soils.

Pastor Pin?eiro, Jesu?s; Milla?n, Roci?o; Herna?ndez, A. J.; Sierra, M. J.; Lobo, M. Carmen

2009-01-01

335

Uptake of radionuclides from soil  

International Nuclear Information System (INIS)

Experiments to determine the transfer factors for the radionuclides 90Sr, 139Cs, 60Co, and 54Mn have been carried out at Juelich research centre since June 1978. A temporary soil contamination caused by an accident (radionuclides entering the 0 to 1 cm soil layer) and a continuous soil contamination (radionuclides entering the 0 to 20 cm topsoil, AP horizon) are simulated. The test plants are agricultural plants such as alfalfa, mixtures of meadow grass, potatoes, sugar beets, winter wheat, spring barley, and clover. If crop rotation on specific soil permits it, also garden cultures such as lettuce, radishes, carrots, and dwarf beans are grown. Preliminary results of the first vegetation period show a wide variation of transfer factors for the radionuclides under investigation in dependence of the type of soil and plant. These variations and the specific dependence of transfer factors on certain soil properties, on the type of plant and its stage of growth at the time of harvesting, on the part of the plant, and on the experimental conditions set a limit to the establishment of a transfer factor to predict the concentration of a radionuclide in a certain plant in a certain soil. Still, it may be possible to give conservative transfer factors for certain types of soil and for the most common crops. (orig.)

336

Brazilian Cerrado Soil Actinobacteria Ecology  

OpenAIRE

A total of 2152 Actinobacteria strains were isolated from native Cerrado (Brazilian Savannah) soils located in Passos, Luminrias, and Arcos municipalities (Minas Gerais State, Brazil). The soils were characterised for chemical and microbiological analysis. The microbial analysis led to the identification of nine genera (Streptomyces, Arthrobacter, Rhodococcus, Amycolatopsis, Microbacterium, Frankia, Leifsonia, Nakamurella, and Kitasatospora) and 92 distinct species in both seasons studied (...

Monique Suela Silva; Alenir Naves Sales; Karina Teixeira Magalhes-Guedes; Disney Ribeiro Dias; Rosane Freitas Schwan

2013-01-01

337

CHEMICAL EQUILIBRIUM OF SOIL SOLUTION IN STEPPE ZONE SOIL  

Directory of Open Access Journals (Sweden)

Full Text Available Dynamics of material composition, migration and accumulation of salts is determined by chemical equilibrium in soil solution. Soil solution contains associated electrically neutral ion pairs CaCO30; CaSO40, MgCO30, MgSO40, charged ion pairs CaHCO3+, MgHCO3+, NaCO3-, NaSO4-, CaOH+, MgOH+. Calculation method is proposed for quantitative assessment of real ion forms in the soil solution of chestnut solonetz soil complex. Were proposed equations to calculate free and associated forms of ions. To solve the equations were used an iteration, a linear interpolation of equilibrium constants, a Method of Ionic Pairs including a law of initial concentration preservation, a law of the operating masses of equilibrium system, the concentration constants of ion pair dissociation on the law of operating masses. Was determined the quantity of ion free form and a coefficient of ion association as ratio of ions free form to analytical content ?e = Cass/Can. The association of ions varies in individual soils and soil layer. Increasing soil solution salinity amplifies the ions association. In form of ionic pairs in soil solution are: 11.8-53.8% of Ca2+; 9.4-57.3% of Mg2+; 0.7-11.9% of Na+; 2.2-22.3% of HCO3-, 11.8-62.7% of SO42-. The ion CO32- is high associated, the share of ions in associated form is up to 92.7%. The degree of soil solution saturation was obtained for three level of approximation accounting on analytical concentration, calculated association coefficient, calculated coefficient of association. Relating to thermodynamic solubility product S0, the mathematical product of analytical ionic pairs indicated super saturation of soil solutions up to K1 = 100, taking into account calculated coefficient of association ion activity super saturation of soil solutions is absent, K3?1. Only for solonetz chestnut meadow K3?2-5. The soil solution saturation degree in soil profile and laterally in landscape varies. The quantitative assessment of real ion forms in the soil solution allows explain evolution of landscape of salted soils, structure of soil cover. Calculations fulfilled show that a possibility of soil degradation scenario taking into account the laws of association of ions in soil solution is much more probable and dangerous than it was assessed before. New understanding of water-salt transfer, geochemical barriers and ecological functions of soil will help to improve rainfed and irrigational agriculture.

A. A. Batukaev

2014-01-01

338

Soil Erosion Threatens Food Production  

Directory of Open Access Journals (Sweden)

Full Text Available Since humans worldwide obtain more than 99.7% of their food (calories from the land and less than 0.3% from the oceans and aquatic ecosystems, preserving cropland and maintaining soil fertility should be of the highest importance to human welfare. Soil erosion is one of the most serious threats facing world food production. Each year about 10 million ha of cropland are lost due to soil erosion, thus reducing the cropland available for world food production. The loss of cropland is a serious problem because the World Health Organization and the Food and Agricultural Organization report that two-thirds of the world population is malnourished. Overall, soil is being lost from agricultural areas 10 to 40 times faster than the rate of soil formation imperiling humanitys food security.

Michael Burgess

2013-08-01

339

How Soil Organic Matter Composition Controls Hexachlorobenzene-Soil-Interactions: Adsorption Isotherms and Quantum Chemical Modelling  

CERN Document Server

Hazardous persistent organic pollutants (POPs) interact in soil with the soil organic matter (SOM) but this interaction is insufficiently understood at the molecular level. We investigated the adsorption of hexachlorobenzene (HCB) on soil samples with systematically modified SOM. These samples included the original soil, the soil modified by adding a hot water extract (HWE) fraction (soil+3 HWE and soil+6 HWE), and the pyrolyzed soil. The SOM contents increased in the order pyrolyzed soil < original soil < soil+3 HWE < soil+6 HWE. For the latter three samples this order was also valid for the HCB adsorption. The pyrolyzed soil adsorbed more HCB than the other samples at low initial concentrations, but at higher concentrations the HCB adsorption became weaker than in the samples with HWE addition. This adsorption behaviour combined with the differences in the chemical composition between the soil samples suggested that alkylated aromatic, phenol, and lignin monomer compounds contributed most to the HC...

Ahmed, Ashour; Khn, Oliver

2013-01-01

340

Role of soil properties in water retention characteristics of main Hungarian soil types  

Directory of Open Access Journals (Sweden)

Full Text Available Relationship between easily available soil properties and soil water retention at given matric potentials were analysed on brown forest soils, chernozems and meadow soils of Hungarian Detailed Soil Hydrophysical Database (Hungarian acronym: MARTHA. We studied the influence of soil properties displayed on the 1:10000 scale Hungarian soil maps on soil water retention at -0.1, -33, -1500 and -150000 kPa. Continuous (particle size distribution, organic matter content, calcium carbonate content and pH and category type (ordinal: soil texture, ordinal type information on organic matter content, calcium carbonate content and pH; nominal: soil subtype classes variables were used in the analyses. The relationships was analysed with random forest method based on conditional inference trees (cforest. Water retention of different soil types was characterized. Importance of soil properties in the prediction of soil water content varies according to soil type and matric potentials.

Brigitta Toth

2014-06-01

341

Evaluation of soil washing for radiologically contaminated soils  

International Nuclear Information System (INIS)

Soil washing has been applied internationally to decontaminate soils due to the widespread increase in environmental awareness manifested in the United States by promulgation of the Comprehensive Environmental Response, Compensation and Liability Act, yet we continue to lack understanding on why the technique works in one application and not in another. A soil washing process typically integrates a variety of modules, each designed to decontaminate the matrix by destroying a particular phase or segregating a particle size fraction in which the contaminants are concentrated. The more known about how the contaminants are fixed, the more likely the process will succeed. Much can be learned from bioavailability studies on heavy metals in soils. Sequential extraction experiments designed to destroy one fixation mechanism at a time can be used to determine how contaminants are bound. This knowledge provides a technical basis for designing a processing strategy to efficiently decontaminate soil while creating a minimum of secondary wastes. In this study, a soil from the Idaho National Engineering Laboratory was physically and chemically characterized, then sequentially extracted to determine if soil washing could be effectively used to remove cesium, cobalt and chromium

342

Soil characteristics driving arbuscular mycorrhizal fungi communities in semiarid soils  

Science.gov (United States)

Arbuscular mycorrhizal fungi (AMF) are an important soil microbial group that affects multiple ecosystems functions and processes, including nutrient cycling, plant productivity and competition, and plant diversity. We carried out a study to investigate AMF communities in the roots and the rhizosphere of Brachypodium retusum (Pers.) Beauv., a common plant species of great ecological importance that grows in different type of soils in semiarid Mediterranean areas with similar climatic conditions. We hypothesized that if both factors, host plant species and climatic conditions, cannot influence the differences in AMF communities in the roots and in the rhizosphere of Brachypodium retusum, variances in AMF richness and diversity could be due to soil characteristics. Hence we study the relationships between physical, chemical and biological soil characteristics and AMF community composition found in the roots and in the rhizospheres. We recorded sixty-seven AMF operational taxonomical units (OTUs). Each soil type presented a different AMF community composition and thus, can be characterized by its own AMF communities. A combination among some of the soil parameters could define the AMF species present in the roots and the rhizosphere of B. retusum. It was the case for calcium, urease, protease and -glucosidase which explained the variation in the AMF communities. In conclusion, soil charactristics can be decisive in the assembling of the AMF communities, managing the diversity and composition of these communities.

Torrecillas, Emma; del Mar Alguacil, Maria; Torres, Pilar; Daz, Gisela; Caravaca, Fuensanta; Montesinos, Alicia; Roldn, Antonio

2014-05-01

343

Mathematical simulation of soil-plant relationships and soil genesis  

Energy Technology Data Exchange (ETDEWEB)

Mathematical simulation is a technique drawn from the engineering disciplines which shows promise in dealing with some problems in soil-plant relationships and soil genesis. Its potential usefulness is derived from the fact that it offers the possibility of making predictions about soil-plant systems in situations which make it unrealistic to obtain data by direct measurement. The predictions are based on simulation of system processes rather than on statistical extrapolation. In this paper three examples are presented in which fairly realistic simulations of the effects of radioactive fallout and fertilization in soil-plant systems have been made. Finally, a proposal is made for an initial approach to the simulation of some aspects of soil formation. If adequate simulation models can be devised for soil formation or system perturbations, it opens the possibility for computer gaming exercises. Such exercises may make it possible to examine the effect of independent variables, such as climate and vegetation, on soil genesis in an experimental setting or to optimize management strategies in the use of fertilizers and pesticides in agriculture. 13 references, 5 figures.

Kline, J.R.

1973-01-01

344

know Soil Know Life - Getting Kids Excited About Soils  

Science.gov (United States)

In the United States soils are often taught in primary school (grade 3-6) but with little excitement or passion. We have been working with schools and teachers to bring our passion about soils to this audience. The methods and message can be conveyed simply and effectively by engaging the students in a dialog and through kinematic learning. Our approach is to begin with a simple question - what are 4 things we cannot live without. The answer - Air, Water, Sunlight, and Soil. Most students say "food, shelter, clothing, plants, animals etc." so we then explain all of those come from soil. This leads us to a quick "dance" illustrating that without soils we would be 'Hungry. Homeless, and Naked". The results are that students and teachers remember this simple message. From this point it is our hope that students will continue to understand the importance of soils and stop treating soils like dirt. Other simple exercises for this younger audience will also be presented.

Lindbo, David L.; Robinson, Clay; Kozlowski, Deborah

2014-05-01

345

Evaluation of soil washing for radiologically contaminated soils  

Energy Technology Data Exchange (ETDEWEB)

Soil washing has been applied internationally to decontaminate soils due to the widespread increase in environmental awareness manifested in the United States by promulgation of the Comprehensive Environmental Response, Compensation and Liability Act, yet we continue to lack understanding on why the technique works in one application and not in another. A soil washing process typically integrates a variety of modules, each designed to decontaminate the matrix by destroying a particular phase or segregating a particle size fraction in which the contaminants are concentrated. The more known about how the contaminants are fixed, the more likely the process will succeed. Much can be learned from bioavailability studies on heavy metals in soils. Sequential extraction experiments designed to destroy one fixation mechanism at a time can be used to determine how contaminants are bound. This knowledge provides a technical basis for designing a processing strategy to efficiently decontaminate soil while creating a minimum of secondary wastes. In this study, a soil from the Idaho National Engineering Laboratory was physically and chemically characterized, then sequentially extracted to determine if soil washing could be effectively used to remove cesium, cobalt and chromium.

Gombert, D. II

1994-03-01

346

Soil management impacts on soil carbon sequestration by switchgrass  

Energy Technology Data Exchange (ETDEWEB)

Increased atmospheric carbon dioxide (CO{sub 2}) could have negative impacts on the environment. Producing and creating bioenergy in the form of biofuels and electricity from crops is a practical approach to reducing CO{sub 2} buildup by displacing fossil fuels and sequestering carbon (C). The use of switchgrass (Panicum virgatum L.) as an energy crop can contribute to clean burning fuels, but no studies addressing soil C sequestration as influenced by use of switchgrass as an energy crop have been conducted. Our objective was to determine the effect of different cultural practices on soil C sequestration under switchgrass. Field experiments were designed to provide differences in row spacing, nitrogen (N) rate, switchgrass cultivar, and harvest frequency on a variety of soils. Our results showed that N application, row spacing, harvest frequency, and switchgrass cultivar did not change soil organic C in the short-term (2-3 yr) after switchgrass establishment. However, after 10 yr under switchgrass soil organic C was 45 and 28% higher at depths of 0-15 and 15-30 cm, respectively, compared with fallowed soil in an adjacent area. It appears that several years of switchgrass culture will be required to realize a soil C sequestration benefit. (author)

Ma, Z.; Wood, C.W.; Bransby, D.I. [Auburn University (United States). Dept. of Agronomy and Soils

2000-07-01

347

40 CFR 796.2750 - Sediment and soil adsorption isotherm.  

Science.gov (United States)

...horizon (i.e., the surface layer of soil). (xiv) Soil texture is a classification of soils that is based...n, and l/n. (7) Soil information: Soil Order, series, texture, sampling location, horizon, general...

2010-07-01

348

Soil-structure interaction on inclined soil layers  

International Nuclear Information System (INIS)

The case history presented deals with a Category I building having two-thirds of its base founded on a wedge of hard material. This wedge is underlain by an inclined layer of softer material, which also directly supports the remaining one-third of the foundation. The inclined layer is underlain by a third material, possessing large stiffness and extending to great depth. This case is analyzed with the methodology described below: - Determination of the static soil compliances by discretizing the foundation area into a number of strips and taking the soil profile as horizontally layered under each strip. Lumped parameter soil compliances for the whole foundation are obtained by weighting the contributions to stiffness in proportion to the area of each strip. - Definition of the degree of coupling between modes. The soil compliances defined in the previous step include coupling between the vertical and rocking modes and the horizontal and torsional modes through the positioning of the corresponding soil springs. The degree of coupling is checked through a static finite element analysis. - Frequency correction of the static soil compliances taking into account the inhomogeneity of the foundation conditions. The correction is based on obtaining dynamic stiffness coefficients for extreme configurations of the soil profile. - Assessment of the sliding potential of the structure under earthquake loading, considering eccentricities of the dynamic forces and non-uniform fricti the dynamic forces and non-uniform friction resistance over the foundation area, accounting for the frictional capacity of the different bearing materials. It is concluded that the simplified technique can provide accurate soil compliances, coupling and frequency corrections for soil-structure interaction on sloping layers, and an appropriate assessment of the sliding potential. (orig./HP)

349

Soil organic carbon covariance with soil water content; a geostatistical analysis in cropland fields  

Science.gov (United States)

Soil texture has traditionally represented the rate of soil water drainage influencing soil water content (WC) in the soil characteristic curves, hydrological models and remote sensing field studies. Although soil organic carbon (OC) has been shown to significantly increase the water holding capacity of soil in individual field studies, evidence is required to consider soil OC as a significant factor in soil WC variability at the scale of a remote sensing footprint (25 km2). The relationship of soil OC to soil WC was evaluated over 50 fields during the Soil Moisture Active Passive (SMAP) soil WC field sampling campaign over southern Manitoba, Canada. On each field, soil WC was measured at 16 sample points, at 100 m spacing to 5 cm depth with Stevens hydra probe sensors on 16 sampling dates from June 7 to July 19, 2012. Soil cores were also taken at sampling sites on each field, each sampling day, to determine gravimetric moisture, bulk density and particle size distribution. On 4 of the sampling dates, soil OC was also determined by loss on ignition on the dried soil samples from all fields. Semivariograms were created from the field mean soil OC and field mean surface soil WC sampled at midrow, over all cropland fields and averaged over all sampling dates. The semivariogram models explained a distinct relationship of both soil OC and WC within the soil over a range of 5 km with a Gaussian curve. The variance in soil that soil OC and WC have in common was a similar Gaussian curve in the cross variogram. Following spatial interpolation with Kriging, the spatial maps of soil OC and WC were also very similar with high covariance over the majority of the sampling area. The close correlation between soil OC and WC suggests they are structurally related in the soil. Soil carbon could thus assist in improving downscaling methods for remotely sensed soil WC and act as a surrogate for interpolation of soil WC.

Manns, H. R.; Berg, A. A.; von Bertoldi, P.

2013-12-01

350

Soil dry aggregate size distribution: effects of soil type and land use  

OpenAIRE

Soil structure is an important physical property of soil and has a great impact on the environment and agriculture. Dry aggregate size distribution and related soil structure indices are essential parameters in understanding the structural state of the soil. This study was conducted to determine the effects of different soil types and land uses on structure parameters and to relate them to selected soil properties. The investigation was performed on five soil types (Arenosols, Fluvisols, Cher...

Ciric, V.; Manojlovic, M.; Lj Nesic; Belic, M.

2012-01-01

351

Evaluation of soil structure in the framework of an overall soil quality rating  

DEFF Research Database (Denmark)

Soil structure is an important aspect of agricultural soil quality, and its preservation and improvement are key to sustaining soil functions. Methods of overall soil quality assessment which include visual soil structure information can be useful tools for monitoring and managing the global soil resource. The aim of the paper is: (i) to demonstrate the role of visual quantification of soil structure within the procedure of the overall soil quality assessment by the Muencheberg Soil Quality Rating (M-SQR), (ii) to quantify the magnitude and variability of soil structure and overall M-SQR on a number of agricultural research sites and (iii) to analyse the correlations of soil quality rating results with crop yields. We analysed visual soil structure and overall soil quality on a range of 20 experimental sites in seven countries. To assess visual soil structure we utilised the Visual Soil Assessment (VSA) and Visual Evaluation of Soil Structure (VESS) methods. Results showed the feasibility and reliability of both VSA and VESS methods and the overall soil quality M-SQR rating approach to give scores and classes which characterised the soil potential for cropping. The structure status of soil can be reliably assessed by these procedures. In soils with clay contents > 30% unfavourable soil structure could not be reliably recognised by measurements of the dry bulk density, but significantly by evaluation of visual soil structure. Structure scores were clearly associated with the drainage status of soil. More than 70% of the variability of crop yields at a given intensity of input may be explained by the overall M-SQR-score which includes information on soil texture, relief and climate in addition to soil structure. We conclude that methods of visual soil assessment are useful diagnostic tools for monitoring and controlling agricultural soil quality over different scales, ranging from within-fields to global. Controlling the drainage status of land and action of machinery at appropriate drainage states are pre-conditions for preserving a suitable soil structure.

Mueller, L; Shepherd, T G

2013-01-01

352

Spatial variation of soil physical properties in adjacent alluvial and colluvial soils under Ustic moisture regime  

OpenAIRE

Soils vary spatially due to differences in soil management and soil formation factors. The soil spatial variability is an important determinant of efficiency of farm inputs and yield. This study was carried out to identify and compare spatial variation of some soil physical properties by geostatistics in alluvial and adjacent colluvial soils formed under ustic moisture regime at Gkhyk State Farm (1750 ha), Amasya, Turkey. Seventy four soil samples were collected on a regular grid (500 ?...

Sag?lam, M.; O?ztu?rk, H. S.; Ers?ahin, S.; I? O?zkan, A.

2011-01-01

353

Long-term Impact of Rotary Method of Soil Mechanical Treatment on Soil Properties  

OpenAIRE

The imitating approach to the technique and technology of soil cultivation excels the influence of natural factors of soil formation and leads to the anthropogenic biosphere degradation. The article fundamentally justifies the rotary soil cultivation in terms of genesis of soil. This method provides the formation of a new layer in the soil depth, which intensifies the geological and biological processes, influences the overlying soil layers, increases the biological productivity of the soil a...

Kalinichenko, Valeriy P.; Sharshak, Vladimir K.; Zinchenko, Vladimir E.; Zarmaev, Ali A.; Ladan, Evgeny P.; Chernenko, Vladimir V.; Ilina, Ludmila P.

2012-01-01

354

Direct soil moisture controls of future global soil carbon changes: An important source of uncertainty  

OpenAIRE

The nature of the climatecarbon cycle feedback depends critically on the response of soil carbon to climate, including changes in moisture. However, soil moisturecarbon feedback responses have not been investigated thoroughly. Uncertainty in the response of soil carbon to soil moisture changes could arise from uncertainty in the relationship between soil moisture and heterotrophic respiration. We used twelve soil moisturerespiration functions (SMRFs) with a soil carbon model (RothC) ...

Fallon, Pete; Jones, Chris D.; Ades, Melanie; Paul, Keryn

2011-01-01

355

The Spatial Variability of Soil Dehydrogenase Activity: A Survey in Urban Soils  

OpenAIRE

Information on soil microorganisms and their activity used to determine microbiological characteristics are very important for soil quality and productivity. Studies of enzyme activities provide information on the biochemical processes occurring in soil. There is growing evidence that soil biological parameters may be potential and sensitive indicators of soil ecological conditions and soil management. Soil microbiological parameters may be evaluated statistically due to application of geosta...

Ridvan Kizilkaya; Tayfun A?kin

2007-01-01

356

Root Patterns in Heterogeneous Soils  

Science.gov (United States)

Heterogeneous water availability is a typical characteristic of soils in which plant roots grow. Despite the intrinsic heterogeneity of soil-plant water relations, we know little about the ways how plants respond to local environmental quality. Furthermore, increasing use of soil amendments as partial water reservoirs in agriculture calls for a better understanding of plant response to soil heterogeneity. Neutron radiography is a non-invasive imaging that is highly sensitive to water and root distribution and that has high capability for monitoring spatial and temporal soil-plant water relations in heterogeneous systems. Maize plants were grown in 25 x 30 x 1 cm aluminum slabs filled with sandy soil. On the right side of the compartments a commercial water absorbent (Geohumus) was mixed with the soil. Geohumus was distributed with two patterns: mixed homogeneously with the soil, and arranged as 1-cm diameter aggregates (Fig. 1). Two irrigation treatments were applied: sufficient water irrigation and moderate water stress. Neutron radiography started 10 days after planting and has been performed twice a day for one week. At the end of the experiment, the containers were opened, the root were removed and dry root weight in different soil segments were measured. Neutron radiography showed root growth tendency towards Geohumus treated parts and preferential water uptake from Geohumus aggregates. Number and length of fine lateral roots were lower in treated areas compared to the non-treated zone and to control soil. Although corn plants showed an overall high proliferation towards the soil water sources, they decreased production of branches and fine root when water was more available near the main root parts. However there was 50% higher C allocation in roots grown in Geohumus compartments, as derived by the relative dry weight of root. The preferential C allocation in treated regions was higher when plants grew under water stress. We conclude that in addition to the inherent effect of water absorbent materials on increasing soil water availability, the distribution pattern of the soil amendments had an important role on root growth strategy and plant water uptake. Neutron radiography of the top, right corner of one sample. The Geohumus is arranged as aggregates.

Dara, A.; Moradi, A. B.; Carminati, A.; Oswald, S. E.

2010-12-01

357

The use of isotopes in soil fertility and soil chemistry  

International Nuclear Information System (INIS)

The concept of radioactive and enriched stable isotopes is reminded. The main topics studied with isotopes which are pointed out are the following: the isotopic exchange and its application; the E and L values; the determination of CEC; the fixing capacity of some ions by the soil particles; the measurement of the A value; the efficiency of fertilizers utilization, the interaction between nutrients, their movements through the soil, the residual effect of the fertilizers and, finally, the root system and soil organic matter. (author)

358

SoilNet - A Zigbee based soil moisture sensor network  

Science.gov (United States)

Soil moisture plays a key role in partitioning water and energy fluxes, in providing moisture to the atmosphere for precipitation, and controlling the pattern of groundwater recharge. Large-scale soil moisture variability is driven by variation of precipitation and radiation in space and time. At local scales, land cover, soil conditions, and topography act to redistribute soil moisture. Despite the importance of soil moisture, it is not yet measured in an operational way, e.g. for a better prediction of hydrological and surface energy fluxes (e.g. runoff, latent heat) at larger scales and in the framework of the development of early warning systems (e.g. flood forecasting) and the management of irrigation systems. The SoilNet project aims to develop a sensor network for the near real-time monitoring of soil moisture changes at high spatial and temporal resolution on the basis of the new low-cost ZigBee radio network that operates on top of the IEEE 802.15.4 standard. The sensor network consists of soil moisture sensors attached to end devices by cables, router devices and a coordinator device. The end devices are buried in the soil and linked wirelessly with nearby aboveground router devices. This ZigBee wireless sensor network design considers channel errors, delays, packet losses, and power and topology constraints. In order to conserve battery power, a reactive routing protocol is used that determines a new route only when it is required. The sensor network is also able to react to external influences, e.g. such as rainfall occurrences. The SoilNet communicator, routing and end devices have been developed by the Forschungszentrum Juelich and will be marketed through external companies. We will present first results of experiments to verify network stability and the accuracy of the soil moisture sensors. Simultaneously, we have developed a data management and visualisation system. We tested the wireless network on a 100 by 100 meter forest plot equipped with 25 end devices each consisting of 6 vertically arranged soil moisture sensors. The next step will be the instrumentation of two small catchments (~30 ha) with a 30 m spacing of the end devices. juelich.de/icg/icg-4/index.php?index=739

Bogena, H. R.; Weuthen, A.; Rosenbaum, U.; Huisman, J. A.; Vereecken, H.

2007-12-01

359

A Review of Fishpond Soil Management Principles in Nigeria  

OpenAIRE

The suitability of sites for culture fisheries depends on the soil. There is therefore the need to have proper background on the nature and properties of soils. The pond oils, soil functions in fish pond, soil characterization, components and soil mineral constituents, oil profile soil classification, soil fertility, nutrients, primary and secondary nutrients, soil organic matter, common soil problems, field and laboratory methods in acid sulphate soil identification, management of acid sulph...

Ekubo, A. T.; Abowei, J. F. N.

2011-01-01

360

Soil CO2 Dynamics in a Tree Island Soil of the Pantanal: The Role of Soil Water Potential  

Science.gov (United States)

The Pantanal is a biodiversity hotspot comprised of a mosaic of landforms that differ in vegetative assemblages and flooding dynamics. Tree islands provide refuge for terrestrial fauna during the flooding period and are particularly important to the regional ecosystem structure. Little soil CO2 research has been conducted in this region. We evaluated soil CO2 dynamics in relation to primary controlling environmental parameters (soil temperature and soil water). Soil respiration was computed using the gradient method using in situ infrared gas analyzers to directly measure CO2 concentration within the soil profile. Due to the cost of the sensors and associated equipment, this study was unreplicated. Rather, we focus on the temporal relationships between soil CO2 efflux and related environmental parameters. Soil CO2 efflux during the study averaged 3.53 mol CO2 m?2 s?1, and was equivalent to an annual soil respiration of 1220 g C m?2 y?1. This efflux value, integrated over a year, is comparable to soil C stocks for 020 cm. Soil water potential was the measured parameter most strongly associated with soil CO2 concentrations, with high CO2 values observed only once soil water potential at the 10 cm depth approached zero. This relationship was exhibited across a spectrum of timescales and was found to be significant at a daily timescale across all seasons using conditional nonparametric spectral Granger causality analysis. Hydrology plays a significant role in controlling CO2 efflux from the tree island soil, with soil CO2 dynamics differing by wetting mechanism. During the wet-up period, direct precipitation infiltrates soil from above and results in pulses of CO2 efflux from soil. The annual flood arrives later, and saturates soil from below. While CO2 concentrations in soil grew very high under both wetting mechanisms, the change in soil CO2 efflux was only significant when soils were wet from above. PMID:23762259

Johnson, Mark S.; Couto, Eduardo Guimares; Pinto Jr, Osvaldo B.; Milesi, Juliana; Santos Amorim, Ricardo S.; Messias, Indira A. M.; Biudes, Marcelo Sacardi

2013-01-01

361

Soil CO? dynamics in a tree island soil of the Pantanal: the role of soil water potential.  

Science.gov (United States)

The Pantanal is a biodiversity hotspot comprised of a mosaic of landforms that differ in vegetative assemblages and flooding dynamics. Tree islands provide refuge for terrestrial fauna during the flooding period and are particularly important to the regional ecosystem structure. Little soil CO? research has been conducted in this region. We evaluated soil CO? dynamics in relation to primary controlling environmental parameters (soil temperature and soil water). Soil respiration was computed using the gradient method using in situ infrared gas analyzers to directly measure CO? concentration within the soil profile. Due to the cost of the sensors and associated equipment, this study was unreplicated. Rather, we focus on the temporal relationships between soil CO? efflux and related environmental parameters. Soil CO? efflux during the study averaged 3.53 mol CO? m? s?, and was equivalent to an annual soil respiration of 1220 g C m? y?. This efflux value, integrated over a year, is comparable to soil C stocks for 0-20 cm. Soil water potential was the measured parameter most strongly associated with soil CO? concentrations, with high CO? values observed only once soil water potential at the 10 cm depth approached zero. This relationship was exhibited across a spectrum of timescales and was found to be significant at a daily timescale across all seasons using conditional nonparametric spectral Granger causality analysis. Hydrology plays a significant role in controlling CO? efflux from the tree island soil, with soil CO? dynamics differing by wetting mechanism. During the wet-up period, direct precipitation infiltrates soil from above and results in pulses of CO? efflux from soil. The annual flood arrives later, and saturates soil from below. While CO? concentrations in soil grew very high under both wetting mechanisms, the change in soil CO? efflux was only significant when soils were wet from above. PMID:23762259

Johnson, Mark S; Couto, Eduardo Guimares; Pinto, Osvaldo B; Milesi, Juliana; Santos Amorim, Ricardo S; Messias, Indira A M; Biudes, Marcelo Sacardi

2013-01-01

362

Tracing soil erosion impacts on soil organisms using 137Cs and soil nematodes  

Science.gov (United States)

The application of environmental radionuclides in soil tracing and erosion studies is now well established in geomorphology. Sediment and erosion-tracing studies are undertaken for a range of purposes in the earth sciences but until now few studies have used the technique to answer biological questions. An experiment was undertaken to measure patterns of soil loss and gain over 50 years, effectively calculating a field-scale sediment budget, to investigate soil erosion relationships between physical and biological soil components. Soil nematodes were identified as a model organism, a ubiquitous and abundant group sensitive to disturbance and thus useful indicator taxa of biological and physico-chemical changes. A field site was selected at the James Hutton Institute's experimental Balruddery Farm in NE Scotland. 10 metre-resolution topographical data was collected with differential GPS. Based on these data, a regular 30 m-resolution sampling grid was constructed in ArcGIS, and a field-sampling campaign undertaken. 104 soil cores (~50 cm-deep) were collected with a percussion corer. Radio-caesium (137Cs) activity concentrations were measured using high-purity germainum gamma-ray spectroscopy, and 137Cs areal activities derived from these values. Organic matter content by loss on ignition and grain-size distribution by laser granulometry were also measured. Additional samples were collected to characterise the soil nematode community, both for abundance and functional (trophic) composition using a combination of low-powered microscopy and molecular identification techniques (dTRFLP). Results were analysed with ArcGIS software using the Spatial Analyst package. Results show that spatial relationships between physical, chemical and biological parameters were complex and interrelated. Previous field management was found to influence these relationships. The results of this experiment highlight the role that soil erosion processes play in medium-term restructuring of the physico-chemical soil environment and the soil community.

Baxter, Craig; Rowan, John S.; McKenzie, Blair M.; Neilson, Roy

2014-05-01

363

Afforestation effects on soil carbon  

DEFF Research Database (Denmark)

Understanding carbon (C) dynamics has become increasingly important due to the major role of C in global warming. Soils store the largest amount of organic C in the biosphere; therefore, changes in this compartment can have a large impact on the C storage of an ecosystem. Land-use change is a main driver of changes in soil organic carbon (SOC) pools worldwide. In Europe, afforestation (i.e. the establishment of new forest on non-forested land), is a major land-use change driven by economic and environmental interests due to its role as a C sequestration tool following the ratification of the Kyoto Protocol. Despite research efforts on the quantification of SOC stock change and soil C fluxes following this land-use change, knowledge is still scarce in regions where afforestation currently is and has been widespread, like Denmark and the rest of Northern Europe. This PhD thesis explored three main aspects of the impact of afforestation on soil C: i) changes in SOC stocks (in forest floors and mineral soils) on afforested cropland in Denmark and in afforested soils of Northern Europe; ii) changes in CH4 oxidation (uptake) potential of soils; iii) changes in soil CO2 efflux through heterotrophic respiration. In Denmark chronosequences (i.e. space-for-time substitution) of oak and Norway spruce stands at the Vestskoven site were the tool used to explore these changes. Soil OC dynamics predicted by the chronosequence approach have often been used, however they never been validated by resampling before. According to the chronosequence approach covering a time span of 40 years, topsoils (0-25 cm soil depth including forest floors) in Vestskoven are currently neither a sink nor a source for C. The more specific decadal trends at the stand level provided by repeated sampling revealed a change in source-sink C balance between soil compartments over time, with C accumulation in the mineral soil becoming increasingly important as the sink strength of forest floors decreased within 4 decades of afforestation. The chronosequence approach is an appropriate tool to assess SOC stock changes following afforestation given that assumptions of similar site conditions are met. However, repeated sampling can not only validate the chronosequence trajectories but also provide refined temporal trends. Changes in SOC in Northern Europe investigated by meta-analysis, revealed that following afforestation, significant C sequestration in soils from this region requires at least three decades or even longer time, when afforestation is performed on former agricultural soils. The faster C accretion in forest floors compensates the initial lag-phase found in mineral soils. The chronosequences also indicated that afforestation increases the CH4 sink potential of soils over time due to the gradual increase in SOC and decrease of bulk density favoring CH4-oxidation, as long as soils remain well drained. The CO2 efflux from soils may increase, due to heterotrophic respiration of a larger SOC pool and not due to higher reactivity of the SOC. However, these C sources are likely to be compensated by the C sink in the growing forest biomass.

Brcena, Teresa G

2013-01-01

364

Decay characteristics of soil thermoluminescence  

International Nuclear Information System (INIS)

Thermoluminescent decay of five different types of soils (soil no. 4FF, Yolo sandy loam, Hanford sandy loam, soil no. 9RDG, and Egbert muck) irradiated by 60Co photons and in the reactor was examined. Although the glow output and the glow curve shapes differed considerably among the soils, the shape of the thermoluminescent decay curves, in general, was quite similar, whether the soil was irradiated by 60Co photons or in the reactor. Regardless of the soil type, the most rapid decay occurred within the first 24 hr after irradiation. After the lapse of sufficient decay time, an apparent isothermal equilibrium state was approached. Curves were fitted to the decay data by the use of a computer program which obtains a weighted least squares fit of a function to the data by means of stepwise Gauss-Newton iterations on the parameters. The results indicated that the thermoluminescent decay curves of soils were hyperbolic [Y= ?(? + X)/sup gamma/ + delta] in form. (U.S.)

365

The soil reference shrinkage curve  

CERN Document Server

A recently proposed model showed how a clay shrinkage curve is transformed to the soil shrinkage curve at the soil clay content higher than a critical one. The objective of the present work was to generalize this model to the soil clay content lower a critical one. I investigated (i) the reference shrinkage curve, that is, one without cracks; (ii) the superficial layer of aggregates, with changed pore structure compared with the intraaggregate matrix; and (iii) soils with sufficiently low clay content where there are large pores inside the intraaggregate clay (so-called lacunar pores). The methodology is based on detail accounting for different contributions to the soil volume and water content during shrinkage. The key point is the calculation of the lacunar pore volume variance at shrinkage. The reference shrinkage curve is determined by eight physical soil parameters: (1) oven-dried specific volume; (2) maximum swelling water content; (3) mean solid density; (4) soil clay content; (5) oven-dried structural...

Chertkov, V Y

2014-01-01

366

Hillslope Soils and Life (Invited)  

Science.gov (United States)

That hillslope processes are impacted by biology has been long understood, but the complexities of the abiotic-biotic processes and their feedbacks are quantitatively emerging with the growing body of pertinent literature. The concept that plants modulate both the disaggregation and transport of soil particles on hillslopes was clearly articulated by G.K. Gilbert. Yet earlier, James Hutton (starting from very different intellectual boundary conditions) argued that soil, which results from the dynamic balance of rock destruction and removal, is a prerequisite for plants - a concept that underscores the need to more deeply examine the feedback of geomorphic processes on terrestrial ecosystems. We compiled the results of recent studies that have been conducted on gentle convex hillslopes across a broad range of rainfall. We found that vegetated landscapes appear to have strong controls on hillslope soil thickness, landscape denudation rates, and soil residence times. The restricted range in residence times - despite large differences in climate - appear in turn to sustain relatively high levels of both nitrogen (N) and phosphorus (P) fertility, suggesting ecological resilience and resistance to non-anthropogenic environmental perturbations. At the most arid end of Earth's climate vegetation disappears, but not all water. The loss of plants shifts soil erosion to abiotic processes, with a corresponding thinning or loss of the soil mantle. This reinforces the hypothesis that a planet without vegetation, but with a hydrologic cycle, would be largely devoid of soil-mantled hillslopes and would be driven toward hillslope morphologies that differ from the familiar convex-up forms of biotic landscapes. While our synthesis of the effects of vegetation on soil production and soil thickness provides a quantitative view of the suggestions of Gilbert, it also identifies that vegetation itself responds to the geomorphic processes, as believed by Hutton. There is a complex interplay between physical and biological processes on the Earth's surface that requires further elucidation in order to fully understand the ramifications of further climatic and physical alteration of our planet's surface.

Amundson, R.; Owen, J. J.; Heimsath, A. M.; Yoo, K.; Dietrich, W. E.

2013-12-01

367

Soil carbon determination by thermogravimetrics  

Directory of Open Access Journals (Sweden)

Full Text Available Determination of soil constituents and structure has a vital role in agriculture generally. Methods for the determination of soil carbon have in particular gained greater currency in recent times because of the potential that soils offer in providing offsets for greenhouse gas (CO2-equivalent emissions. Ideally, soil carbon which can also be quite diverse in its makeup and origin, should be measureable by readily accessible, affordable and reliable means. Loss-on-ignition is still a widely used method being suitably simple and available but may have limitations for soil C monitoring. How can these limitations be better defined and understood where such a method is required to detect relatively small changes during soil-C building?Thermogravimetric (TGA instrumentation to measure carbonaceous components has become more interesting because of its potential to separate carbon and other components using very precise and variable heating programs. TGA related studies were undertaken to assist our understanding in the quantification of soil carbon when using methods such as loss-on-ignition. Combining instrumentation so that mass changes can be monitored by mass spectrometer ion currents has elucidated otherwise hidden features of thermal methods enabling the interpretation and evaluation of mass-loss patterns. Soil thermogravimetric work has indicated that loss-on-ignition methods are best constrained to temperatures from 200 to 430C for reliable determination for soil organic carbon especially where clay content is higher. In the absence of C-specific detection where mass only changes are relied upon, exceeding this temperature incurs increasing contributions from inorganic sources adding to mass losses with diminishing contributions related to organic matter. The smaller amounts of probably more recalcitrant organic matter released at the higher temperatures may represent mineral associated material and/or simply more refractory forms.

Robert Pallasser

2013-02-01

368

Methods of soil organic carbon determination in Brazilian savannah soils  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english Several methods exist for determining soil organic carbon, and each one has its own advantages and limitations. Consequently, a comparison of the experimental results obtained when these methods are employed is hampered, causing problems in the comparison of carbon stocks in soils. This study aimed [...] at evaluating the analytical procedures used in the determination of carbon and their relationships with soil mineralogy and texture. Wet combustion methods, including Walkley-Black, Mebius and Colorimetric determination as well as dry combustion methods, such as Elemental and Gravimetric Analysis were used. Quantitative textural and mineralogical (kaolinite, goethite and gibbsite) analyses were also carried out. The wet digestion methods underestimated the concentration of organic carbon, while the gravimetric method overestimated. Soil mineralogy interfered with the determination of carbon, with emphasis on the gravimetric method that was greatly influenced by gibbsite.

Juliana Hiromi, Sato; Ccero Clio de, Figueiredo; Roblio Leandro, Marcho; Beta Emke, Madari; Luiz Eduardo Celino, Benedito; Jader Galba, Busato; Diego Mendes de, Souza.

2014-08-01

369

Radionuclides distribution coefficient of soil to soil-solution  

International Nuclear Information System (INIS)

The present book addresses various issues related with the coefficient of radionuclides distribution between soil and soil solution. It consists of six sections and two appendices. The second section, following an introductory one, describes the definition of the coefficient and a procedures of its calculation. The third section deals with the application of the distribution coefficient to the prediction of movements of radionuclides through soil. Various methods for measuring the coefficient are described in the fourth section. The next section discusses a variety of factors (physical and chemical) that can affect the distribution coefficient. Measurements of the coefficient for different types of oils are listed in the sixth section. An appendix is attached to the book to show various models that can be helpful in applying the coefficient of distribution of radionuclides moving from soil into agricultural plants. (N.K.)

370

Uranium soils integrated demonstration: Soil characterization project report  

International Nuclear Information System (INIS)

An Integrated Demonstration Program, hosted by the Fernald Environmental Management Project (FEMP), has been established for investigating technologies applicable to the characterization and remediation of soils contaminated with uranium. Critical to the design of relevant treatment technologies is detailed information on the chemical and physical characteristics of the uranium waste-form. To address this need a soil sampling and characterization program was initiated which makes use of a variety of standard analytical techniques coupled with state-of-the-art microscopy and spectroscopy techniques. Sample representativeness is evaluated through the development of conceptual models in an effort to identify and understand those geochemical processes governing the behavior of uranium in FEMP soils. Many of the initial results have significant implications for the design of soil treatment technologies for application at the FEMP

371

Soil Organic Carbon dynamics in agricultural soils of Veneto Region  

Science.gov (United States)

One of the eight soil threats expressed in the European Commission's Thematic Strategy for Soil Protection (COM (2006)231 final) it's the decline in Soil Organic Matter (SOM). His preservation is recognized as with the objective to ensure that the soils of Europe remain healthy and capable of supporting human activities and ecosystems. One of the key goals of the strategy is to maintain and improve Soil Organic Carbon (SOC) levels. As climate change is identified as a common element in many of the soil threats, the European Commission (EC) intends to assess the actual contribution of the soil protection to climate change mitigation and the effects of climate change on the possible depletion of SOM. A substantial proportion of European land is occupied by agriculture, and consequently plays a crucial role in maintaining natural resources. Organic carbon preservation and sequestration in the EU's agricultural soils could have some potential to mitigate the effects of climate change, particularly linked to preventing certain land use changes and maintaining SOC stocks. The objective of this study is to assess the SOC dynamics in agricultural soils (cropland and grassland) at regional scale, focusing on changes due to land use. A sub-objective would be the evaluation of the most used land management practices and their effect on SOC content. This assessment aims to determine the geographical distribution of the potential GHG mitigation options, focusing on hot spots in the EU, where mitigation actions would be particularly efficient and is linked with the on-going work in the JRC SOIL Action. The pilot area is Veneto Region. The data available are coming from different sources, timing and involve different variables as: soil texture, climate, soil disturbance, managements and nutrients. The first source of data is the LUCAS project (Land Use/Land Cover Area Frame statistical Survey). Started in 2001, the LUCAS project aims to monitor changes in land cover/use and management of the EU territory by field observations of geo-referenced points. In 2009, a topsoil (0-30 cm) module was included to the survey and a subset of around 21,000 sites was sampled in 23 Member States. The second source is a soil survey monitoring pilot campaign carried in Veneto Region last year. The pilot campaign has been organized with the collaboration between JRC, University of Padova and ARPAV Veneto. The scope was to apply the LUCAS methodology to an experimental soil survey of 40 samples. The selection of the points to survey has been done on the basis of the LUCAS project related to Veneto Region, pedo-climatic and management unit conditions and the database on soils belonging to ARPAV Soil Unit, collected ante 2000. Data started to be investigated and permit to show changes in SOC content in a decade for different land use/cover and climatic areas. Through the bulk density data collected and the data already available from ARPAV library, it's possible to evaluate the Carbon stocks of Veneto region. Possible changes in Carbon can be related to land use changes and different strategies of management practices adopted over time.

Bampa, F. B.; Morari, F. M.; Hiederer, R. H.; Toth, G. T.; Giandon, P. G.; Vinci, I. V.; Montanarella, L. M.; Nocita, M.

2012-04-01

372

Soil Data Analysis Using Classification Techniques and Soil Attribute Prediction  

Directory of Open Access Journals (Sweden)

Full Text Available Agricultural research has been profited by technical advances such as automation, data mining. Today ,data mining is used in a vast areas and many off-the-shelf data mining system products and domain specific data mining application soft wares are available, but data mining in agricultural soil datasets is a relatively a young research field. The large amounts of data that are nowadays virtually harvested along with the crops have to be analyzed and should be used to their full extent. This research aims at analysis of soil dataset using data mining techniques. It focuses on classification of soil using various algorithms available. Another important purpose is to predict untested attributes using regression technique, and implementation of automated soil sample classification.

Jay Gholap

2012-05-01

373

Soil test for some micronutrients and selenium in Egyptian soil  

International Nuclear Information System (INIS)

Several factors have simulated the need for research on the development of soil tests for micronutrients. Increased crop yield have resulted in more attention being given to the need for these elements. One of the most effective means of determining whether a particular nutrient is limiting or not is the soil test. Many studies were established in our department in order to find out the best-fit method for the most reliable estimation of some micronutrients such as: Mn, Fe, Zn and Se. Tracer technique was used as a method for determining these elements in different soils of Egypt. A review of pertinent research concerning types of extractants, the need for considering other soil properties in interpretation, and critical levels are presented

374

Cesium-137 in Montana soils  

International Nuclear Information System (INIS)

Fallout 137Cs levels in soil were measured at 11 diverse sites throughout Montana. Concentrations in near-surface samples ranged from 20-200 mBq g-1 (0.51-5.41 pCi g-1). Most of the 137Cs was in the top 10 cm of soil. Deeper occurrences were attributed to disturbances by animals and to interstitial flow of small sediment particles within saturated soils. The areal concentrations ranged from 130-748 mBq cm-2 (3.6-20.2 pCi cm-2) and were highly correlated with annual precipitation

375

Optimization of electrochemical soil decontamination  

International Nuclear Information System (INIS)

At the Czech Technical University in Prague, soil decontamination techniques have been studied for several years. The leaching procedures (batch or 'sorption' leaching) did not allow to achieve more than 30% caesium desorption. Caesium thermodesorption was demonstrated not to be very efficient either; quantitative caesium separation could be achieved only from solutions resulting from fusion of the soil with special fluxes. The most promising results were achieved by electrolytic decontamination. In preliminary experiments, more than 97% of caesium was released from soils contaminated long time ago. The aim of this study was to perform optimisation of the parameters of this method. (orig.)

376

Soil Erosion Threatens Food Production  

OpenAIRE

Since humans worldwide obtain more than 99.7% of their food (calories) from the land and less than 0.3% from the oceans and aquatic ecosystems, preserving cropland and maintaining soil fertility should be of the highest importance to human welfare. Soil erosion is one of the most serious threats facing world food production. Each year about 10 million ha of cropland are lost due to soil erosion, thus reducing the cropland available for world food production. The loss of cropland is a serious ...

Michael Burgess; David Pimentel

2013-01-01

377

Salt overload: How quickly does road salt move from road to groundwater to stream in Baltimore County, MD and what are the effects on soil, groundwater, and stream chemistry?  

Science.gov (United States)

The portion of the landscape covered by roads and other impervious surfaces has increased over the last 50 years. Concurrently, application of road salt, primarily sodium chloride (NaCl), as a de-icer has increased in areas of North America with regular ice and snowfall events. Over the last 10 - 15 years, numerous investigators reported that decades of road salt application has resulted in growing concentrations of sodium and chloride in groundwater and surface water. These road salt-derived elements are present at elevated levels in the surface and groundwaters of impacted watersheds year round. An understudied aspect of road salt impacts has been the role that stormwater management basins (SMBs) play in altering the timing and location of road salt loading to urban and suburban groundwater-surface water systems. SMBs have become common in construction and development over the last 15-20 years. One of the major goals of SMBs is to decrease direct runoff from impervious surfaces to streams by redirecting that runoff into shallow groundwater and thus reducing the flashiness of streams in urban and suburban areas. An unintended consequence of SMBs is that road salt runoff from impervious surfaces is focused into the SMBs and loaded into the vadose zone and shallow groundwater in the winter and then exported to surface water throughout the year. As part of an onging project in a suburb northwest of Baltimore, MD, water samples were collected several times a year from groundwater below two SMBs, a shallow groundwater aquifer downgradient of the SMBs, and a second-order stream for which the aquifer provides baseflow. The major elemental chemistry of the samples was measured. Conductivity and water level loggers were installed to collect data in wells and surface water between grab sampling events. The logger records will be analyzed using spatio-temporal data mining techniques to extract important patterns in the data and to highlight and understand seasonal trends and storm events. A persistent groundwater plume of water with high NaCl concentrations is present below the SMBs and downgradient in the shallow groundwater aquifer. Concentrations vary seasonally with the highest concentrations in the winter and early spring. Na+ clearly interacts with the cation exchange complex (CEC) along a flowpath between the SMB and the stream. As a result, the Na:Cl ratio falls from 1:1 in groundwater below the SMBs to as low as ~1:10 and also seems to vary seasonally along the flowpath. Preliminary measurements of the CEC show that the Ca:Na ratio decreases by a factor of 2 - 5 in soil and aquifer materials affected by road salt. Preliminary strontium (Sr) isotope data indicate that groundwater and CEC within the road salt plumes are similar to Sr isotope values for seawater and are isotopically distinct from the relatively radiogenic natural weathering Sr isotope signal. Our findings indicate that SMBs increase the residence time of road salt in groundwater and stream systems with potential negative implications for ecosystems downgradient of SMBs.

Moore, J.; Sandosky, B.; McGuire, M.; Casey, R.; Snodgrass, J.; Lev, S. M.

2013-12-01

378

Soils apart from equilibrium consequences for soil carbon balance modelling  

Directory of Open Access Journals (Sweden)

Full Text Available Many projections of the soil carbon sink or source are based on kinetically defined carbon pool models. Parameters of these models are often determined in a way that the steady state of the model matches observed carbon stocks. The underlying simplifying assumption is that observed carbon stocks are near equilibrium. This assumption is challenged by observations of very old soils that do still accumulate carbon. In this modelling study we explored the consequences of the case where soils are apart from equilibrium. Calculation of equilibrium states of soils that are currently accumulating small amounts of carbon were performed using the Yasso model. It was found that already very small current accumulation rates cause big changes in theoretical equilibrium stocks, which can virtually approach infinity. We conclude that soils that have been disturbed several centuries ago are not in equilibrium but in a transient state because of the slowly ongoing accumulation of the slowest pool. A first consequence is that model calibrations to current carbon stocks that assume equilibrium state, overestimate the decay rate of the slowest pool. A second consequence is that spin-up runs (simulations until equilibrium overestimate stocks of recently disturbed sites. In order to account for these consequences, we propose a transient correction. This correction prescribes a lower decay rate of the slowest pool and accounts for disturbances in the past by decreasing the spin-up-run predicted stocks to match an independent estimate of current soil carbon stocks. Application of this transient correction at a Central European beech forest site with a typical disturbance history resulted in an additional carbon fixation of 5.71.5 tC/ha within 100 years. Carbon storage capacity of forest soils is potentially much higher than currently assumed. Simulations that do not adequately account for the transient state of soil carbon stocks neglect a substantial amount of current carbon accumulation.

T. Wutzler

2006-10-01

379

Quantifying soil complexity using network models of soil porous structure  

Directory of Open Access Journals (Sweden)

Full Text Available This paper describes an investigation into the properties of spatially embedded complex networks representing the porous architecture of soil systems. We suggest an approach to quantify the complexity of soil pore structure based on the node-node link correlation properties of the networks. We show that the complexity depends on the strength of spatial embedding of the network and that this is related to the transition from a non-compact to compact phase of the network.

M. Samec

2013-01-01

380

Deformation Parameters of Macrofragment Soils in Soil Dams  

OpenAIRE

The author tries to generalize the results of testing of macrofragment soils, made by other authors and to give recommendations on defining nonlinear model soils parameters. The article gives definitions of volume weight of gravel and pebble ground and mined rock. Its shown that starting shift modules depending on stress due to prestress can be described in power formula. The author confirms Professor L.N. Rasskazovs idea about the possibility of describing volume deformation in contrac...

Sainov Mikhail Petrovich

2014-01-01

381

Relationship between 85Sr sorption by soils and soil characteristics  

International Nuclear Information System (INIS)

Taking correlation coefficients into account, the statistical processing of the results of measurements of 10 characteristics of soils from the surroundings of the nuclear power plants Mochove and Dukovany showed that 85Sr sorption is mostly influenced by the proportion of 0.01 and 0.001 mm fractions, the humus content and pH/KCl. The obtained equations of multiple regression allow a rough estimation of the percentage sorption of 85Sr in soils with known characteristics. (author)

382

Soils - Part 6: Phosphorus and Potassium in the Soil  

Science.gov (United States)

This lesson explains the importance of phosphorus fixation and describes methods for applying phosphorus and the advantages (and disadvantages) of each. It also describes the three forms of potassium and how form determines availability of potassium to plants.[This lesson, as well as the other nine lessons in the Soils series, is taken from the "Soils Home Study Course," published in 1999 by the University of Nebraska Cooperative Extension.

383

Adaptative responses of soil eukaryotic micoorganisms to soil metal contaminations  

OpenAIRE

Heavy metal-polluted soils are colonised by microbial communities which have developed different adaptations that allow them to resist to these pollutants. The objectives of this study were to reveal at the molecular level the diversity of these adaptations. To this aim,we implemented an innovative approach based upon the analysis of soil eukaryotic metatranscriptome to compare resistance mechanisms expressed by eukaryotic microorganisms living in heavy metal contaminated and control non cont...

Lehembre, Fre?de?ric

2009-01-01

384

A method to detect soil carbon degradation during soil erosion  

OpenAIRE

Soil erosion has been discussed intensively but controversial both as a significant source or a significant sink of atmospheric carbon possibly explaining the gap in the global carbon budget. One of the major points of discussion has been whether or not carbon is degraded and mineralized to CO2 during detachment, transport and deposition of soil material. By combining the caesium-137 (137Cs) approach (quantification of erosion rates) with stable c...

Conen, F.; Schaub, M.; Alewell, C.

2009-01-01

385

Soil survey - a basis for european soil protection  

International Nuclear Information System (INIS)

The information available on soils varies greatly from country to country. In view of the fact that, together with water, soils represent the most important natural resource in the EC, it is recommended that steps should be taken to ensure a reasonable level of information for all countries and that emphasis be placed on assembling an adequate database. Such information is fundamental to future land use and environmental protection

386

The use of some soil aggregate indices to assess potential soil loss in soils of south-eastern nigeria  

OpenAIRE

Six aggregate indices and some soil properties were evaluated to predict potential soil loss in soils of Southeastern Nigeria. Of the aggregate indices tested, dispersion ratio (DR), Wischmeier's erodibility index (K), clay dispersion index (CDI) and clay floccula-tion index (CFI) ranked higher than geometric mean diameter (GMD) and mean-weight diameter (MWD) in predicting potential soil loss. Some aggregate indices found to correlate well with soil loss are in order of decreasing predictabil...

Mbagwu, J. S. C.; Akamigbo, F. O. R.; Ca, Igwe

1995-01-01

387

Soil CO2 Dynamics in a Tree Island Soil of the Pantanal: The Role of Soil Water Potential  

OpenAIRE

The Pantanal is a biodiversity hotspot comprised of a mosaic of landforms that differ in vegetative assemblages and flooding dynamics. Tree islands provide refuge for terrestrial fauna during the flooding period and are particularly important to the regional ecosystem structure. Little soil CO2 research has been conducted in this region. We evaluated soil CO2 dynamics in relation to primary controlling environmental parameters (soil temperature and soil water). Soil respiration was computed u...

Johnson, Mark S.; Couto, Eduardo Guimara?es; Pinto Jr, Osvaldo B.; Milesi, Juliana; Santos Amorim, Ricardo S.; Messias, Indira A. M.; Biudes, Marcelo Sacardi

2013-01-01

388

Elementary GLOBE Unit: The Scoop on Soils  

Science.gov (United States)

In this book and activities set, tThe GLOBE Kids are on the trail of Scoop, an eager dog who loves to dig holes in the soil. At each hole Scoop has dug, the kids make observations of the soil, learn about soil color, texture, structure, and about the treasures one can find in soil. *Activity 1: Getting to Know Soil* Students learn about soil profiles and the different properties of soil, including texture, color, and size. They will know that soil forms layers based on these properties. *Activity 2: Soil Treasure Hunt* Students learn about things found in soil, such as rocks, roots, critters, and organic material. They will understand that animals and microorganisms aid in the decomposition process that contributes organic materials to soil. *Activity 3: We All Need Soil!* Students will understand the importance of soil science and that soil is a limited resource on Earth. They will learn about soils function for plants and animals. The Elementary GLOBE unit was designed to introduce K-4 students to the study of Earth System Science. It includes five storybooks and 15 learning activities. The science content provided in the books serves as a springboard to GLOBEs scientific protocols, and also provides student with an introduction to technology, a basic understanding of the methods of inquiry, and connections to math and literacy skills. Each book has associated hands-on learning activities to support learning exploration.

Becca Hatheway

2006-01-01

389

Occurrence of entomopathogenic fungi in arable soil  

Directory of Open Access Journals (Sweden)

Full Text Available Samples of soil were taken from arable field and from balk. Larvae of Galleria mellonella and Ephestia khniella were used as an "insect bait" for isolation of entomopathogenic fungi from soil. Metarhizium anisopliae and Paecilomyces fumosoroseus were isolated from both kind of soil. but Beauveria bassiana was present only in soil taken from balk.

Ryszard Mi?tkiewski

1993-06-01

390

Getting a Feel for Soils - Lab  

Science.gov (United States)

This is a lab activity in which students start to put together what they have learned as separate soil attributes in the context of the world they know. This activity involves hypothesizing geologic and soils relationships using state and world maps, conducting texture-by-feel tests, reflecting on the definition of 'soil', and evaluating soil granulometric methods.

Fadem, Cynthia

391

Fusarium Species Isolated from Forest Soil Samples  

OpenAIRE

A total of 46 isolates of Fusarium were isolated from six forest soil samples in Muka Head, Teluk Bahang, Pulau Pinang. Two Fusarium species were identified from the soil samples namely, F. solani (93.5%) and F. oxysporum (6.5%). The present study showed that the diversity and occurrences of Fusarium species in forest soil was low compared to cultivated soils.

Azaman, R. S.; Latiffah, Z.

2011-01-01

392

Soil-Structural Stability as Affected by Clay Mineralogy, Soil Texture and Polyacrylamide Application  

Science.gov (United States)

Soil-structural stability (expressed in terms of aggregate stability and pore size distribution) depends on (i) soil inherent properties, (ii) extrinsic condition prevailing in the soil that may vary temporally and spatially, and (iii) addition of soil amendments. Different soil management practices...

393

EuroSoil2012: Soil science for the benefit of mankind and environment  

Science.gov (United States)

EuroSoil2012 was convened in Bari ITALY from 2-6 July 2012 as the 4th International Congress of the European Confederation of Soil Science Societies (ECSSS). The theme of EuroSoil2012 as soil science for the benefit of mankind and environment aimed to cover several broad aspects of soil science w...

394

Soil acidification in forest and organic soils in Alberta  

Energy Technology Data Exchange (ETDEWEB)

The Terrestrial Environmental Effects Monitoring Committee (TEEM) of the Wood Buffalo Environmental Association (WBEA) is jointly funded by all oil sand industries in northern Alberta to monitor the environmental impacts associated with oil sand mining in the Athabasca deposit. Soil acidification is among the environmental effects that are monitored. TEEM represents industry, government, regional communities, First Nations and non-governmental environmental stakeholders. The program is based on 15 permanent monitoring stations located across the acidifying deposition gradient from near the emission sources to about 120 km from the emission sources. Ten passive dry deposition monitors, 1 wet deposition monitor and dispersion modeling are used to estimate the acidic deposition at these sites. Sampling and assessment of the sites is conducted at 6 year intervals, beginning in 1998. Sampling and assessment near the emission sources is conducted at 3 year intervals. The assessment of vegetation performance included radial and height growth of trees, biodiversity and percent cover of forest floor vegetation. The assessment of soil chemistry included soil stratification by depth and by zone in relation to trees. Soil samples were analyzed for base saturation, base cation:aluminium, base cations, nitrogen and sulphur. No soil chemistry gradient corresponding to the acidic deposition gradient was observed in 1998. Once the data for 2004 becomes available, it will be compared with soil chemistry data from 1998 to find evidence of change related to the deposition gradient. The monitoring program is an fundamental part of acidifying emissions management in the region.

Pauls, R.

2005-07-01

395

Worldwide organic soil carbon and nitrogen data  

Energy Technology Data Exchange (ETDEWEB)

The objective of the research presented in this package was to identify data that could be used to estimate the size of the soil organic carbon pool under relatively undisturbed soil conditions. A subset of the data can be used to estimate amounts of soil carbon storage at equilibrium with natural soil-forming factors. The magnitude of soil properties so defined is a resulting nonequilibrium values for carbon storage. Variation in these values is due to differences in local and geographic soil-forming factors. Therefore, information is included on location, soil nitrogen content, climate, and vegetation along with carbon density and variation.

Zinke, P.J.; Stangenberger, A.G. [Univ. of California, Berkeley, CA (United States). Dept. of Forestry and Resource Management; Post, W.M.; Emanual, W.R.; Olson, J.S. [Oak Ridge National Lab., TN (United States)

1986-09-01

396

Physical and Chemical Characteristics of Dokdo Soil  

OpenAIRE

To understand the properties of soil in Dokdo, we collected soil samples from 12 locations on Seodo and 23 locations on Dongdo, in Dokdo of Gyeongsangbuk-do Province in 2007-2008 and analyzed the soils physical and chemical characteristics. Sand comprises the largest component (49.37%) of Dokdo soil, followed by silt (40.70%) and clay (9.93%). The soil structure consists mostly of sand loam, followed by loam and silt loam. The pH level of soils from Dokdo varied dramatically among sampling...

Gil Seong Lee; Yeon Sik Choo

2009-01-01

397

Stocks of organic carbon in Estonian soils  

OpenAIRE

The soil organic carbon (SOC) stocks (Mg ha1) ofautomorphic mineral (9 soil groups), hydromorphic mineral (7), and lowland organic soils (4) are given for the soil cover or solum layer as a whole and also for its epipedon (topsoil) layer. The SOC stocks for forest, arable lands, and grasslands and for the entire Estonian soil cover were calculated on the basis of the mean SOC stock and distribution area of the respective soil type. In the Estonian soil cover (42 400 km2), a total of 593.8 ...

Ko?lli, Raimo; Ellerma?e, Olav; Ko?ster, Tiia; Lemetti, Illar; Asi, Endla; Kauer, Karin

2009-01-01

398

Impact of soil properties on selected pharmaceuticals adsorption in soils  

Science.gov (United States)

The presence of human and veterinary pharmaceuticals in the environment has been recognized as a potential threat. Pharmaceuticals may contaminate soils and consequently surface and groundwater. Study was therefore focused on the evaluation of selected pharmaceuticals adsorption in soils, as one of the parameters, which are necessary to know when assessing contaminant transport in soils. The goals of this study were: (1) to select representative soils of the Czech Republic and to measure soil physical and chemical properties; (2) to measure adsorption isotherms of selected pharmaceuticals; (3) to evaluate impact of soil properties on pharmaceutical adsorptions and to propose pedotransfer rules for estimating adsorption coefficients from the measured soil properties. Batch sorption tests were performed for 6 selected pharmaceuticals (beta blockers Atenolol and Metoprolol, anticonvulsant Carbamazepin, and antibiotics Clarithromycin, Trimetoprim and Sulfamethoxazol) and 13 representative soils (soil samples from surface horizons of 11 different soil types and 2 substrates). The Freundlich equations were used to describe adsorption isotherms. The simple correlations between measured physical and chemical soil properties (soil particle density, soil texture, oxidable organic carbon content, CaCO3 content, pH_H2O, pH_KCl, exchangeable acidity, cation exchange capacity, hydrolytic acidity, basic cation saturation, sorption complex saturation, salinity), and the Freundlich adsorption coefficients were assessed using Pearson correlation coefficient. Then multiple-linear regressions were applied to predict the Freundlich adsorption coefficients from measured soil properties. The largest adsorption was measured for Clarithromycin (average value of 227.1) and decreased as follows: Trimetoprim (22.5), Metoprolol (9.0), Atenolol (6.6), Carbamazepin (2.7), Sulfamethoxazol (1.9). Absorption coefficients for Atenolol and Metoprolol closely correlated (R=0.85), and both were also related to absorption coefficients of Carbamazepin (R=0.67 and 0.68). Positive correlation was found between Trimetoprim absorption coefficients and Atenolol, Metoprolol or Carbamazepin absorption coefficients. The negative relationship was found between absorption coefficients of Sulfomethoxazol and Clarithromycin (R=-0.80). Sulfamethoxazol absorption coefficient was negatively related to pH_H2O, pH_KCL or sorption complex saturation and positively to the hydrolytic acidity or exchangeable acidity. Trimetoprim absorption coefficient was positively related to the oxidable organic carbon content, cation exchange capacity, basic cation saturation or silt content and negatively to particle density or sand content. Clarithromycin absorption coefficient was positively related to pH_H2O, pH_KCL, CaCO3 content, basic cation saturation or sorption complex saturation and negatively to hydrolytic acidity or exchangeable acidity. Atenolol and Metoprolol absorption coefficients were positively related to the oxidable organic carbon content, cation exchange capacity, basic cation saturation, salinity, clay content or silt content, and negatively to the particle density or sand content. Finally Carbamazepin absorption coefficient was positively related to the oxidable organic carbon content, cation exchange capacity or basic cation saturation, and negatively to the particle density or sand content. Evaluated pedotransfer rules for different pharmaceuticals included different sets of soil properties. Absorption coefficients could be predicted from: the hydrolytic acidity (Sulfamethoxazol), the oxidable organic carbon content (Trimetoprim and Carbamazepin), the oxidable organic carbon content, hydrolytic acidity and cation exchange capacity (Clarithromycin), the basic cation saturation (Atenolol and Metoprolol). Acknowledgement: Authors acknowledge the financial support of the Czech Science Foundation (Project No. 13-12477S).

Kodesova, Radka; Kocarek, Martin; Klement, Ales; Fer, Miroslav; Golovko, Oksana; Grabic, Roman; Jaksik, Ondrej

2014-05-01

399

Ash in the Soil System  

Science.gov (United States)

Ash is the organic and inorganic residue produced by combustion, under laboratory and field conditions. This definition is far away to be accepted. Some researchers consider ash only as the inorganic part, others include also the material not completely combusted as charcoal or biochar. There is a need to have a convergence about this question and define clear "what means ash". After the fire and after spread ash onto soil surface, soil properties can be substantially changed depending on ash properties, that can be different according to the burned residue (e.g wood, coal, solid waste, peppermill, animal residues), material treatment before burning, time of exposition and storage conditions. Ash produced in boilers is different from the produced in fires because of the material diferent propertie and burning conditions. In addition, the ash produced in boilers is frequently treated (e.g pelletization, granulation, self curing) previously to application, to reduce the negative effects on soil (e.g rapid increase of pH, mycorrhiza, fine roots of trees and microfauna). These treatments normally reduce the rate of nutrients dissolution. In fires this does not happen. Thus the implications on soil properties are logically different. Depending on the combustion temperature and/or severity, ash could have different physical (e.g texture, wettability) and chemical properties (e.g amount and type of total and leached nutrients) and this will have implications on soil. Ash can increase and decrease soil aggregation, wettablity and water retention, bulk density, runoff and water infiltration. Normally, ash increases soil pH, Electrical Conductivity, and the amount of some basic nutrients as calcium, magnesium, sodium and potassium. However it is also a potential source of heavy metals, especially if ash pH is low. However the effect of ash on soil in space and time depends especially of the ash amount and characteristics, fire temperature, severity, topography, aspect, climate/meteorological conditions after the ash spread/fire and soil background characteristics. In addition, after the fire heating can change soil original properties increasing the complexity of the ash effects on soil properties. After fire, ash is highly dynamic and very easily transported by wind until the first rains. When wetted, ash compacts and binds onto soil surface, and wind has low capacity to transport it. The post-rain ash dynamic is influenced by water erosion (in slope areas), infiltration into soil profile and vegetation recuperation. This means that ash produced in one place will have implications in other areas, including not burned areas (e.g wind transport and water erosion). This is a clear indication that ash effects go much further than the fire affected area. Due the heterogeneity of soil and ash properties and their dynamic across the landscape, the impacts of ash on soil system can be diverse, producing a mosaic of different effects and responses after ash treatment and/ or fire. In this communication it will be presented and discussed the advances and scientific development of ash effects and dynamic in soil system.

Pereira, P.

2012-04-01

400

Phytoremediation of Soil Trace Elements  

Science.gov (United States)

Phytoremediation includes several distinct approaches to using plants to achieve soil remediation goals. Phytoextraction uses rare hyperaccumulator plants to accumulate in their shoots enough metals per year to achieve decontamination goals. Phytomining uses hyperaccumulators and biomass burn to pro...

401

Scientists Sift Through Urban Soils  

Science.gov (United States)

City soil gets tramped on, dumped on, and pushed around, but some soil scientists are carefully examining what is underfoot in urban areas. During a 3 May session on urban soils at the European Geosciences Union's General Assembly in Vienna, Austria, scientists discussed various aspects of city dirt. In a presentation about the large amount of rubble from buildings that were bombed during World War II, Beate Mekiffer with the Soil Protection Group at the Berlin Institute of Technology, Germany, noted that the sulfate concentration in Berlin's upper aquifer has increased continuously for decades. Many areas in Berlin now exceed a 240-milligram-per-liter precaution value for sulfate in drinking water, according to Mekiffer.

Showstack, Randy

2010-05-01

402

Proceedings of hydrocarbon contaminated soils  

International Nuclear Information System (INIS)

While the 1980s witnessed a concentrated effort toward identifying the scientific concerns associated with hydrocarbon contaminated soils, the 1990s offer the hope that even more reliable solutions, both scientific and regulatory, will emerge. The hope for this transition from problem identification to problems solution is evident in these papers from the 5th Annual Conference on Hydrocarbon Contaminated Soils (formerly called Petroleum Contaminated Soils), as the presentations more clearly reflect the maturation of a rapidly evolving field in the areas of chemical analysis, fate, remediation, public health, and regulatory evaluation. This book attempts to address the multidimensional facets of soil contamination by providing various current general perspectives as well as those from the regulatory and the international communities. Technical information is also provided in specific contamination areas such as diesel fuel, as well as analysis and site assessment, remediation, risk assessment, and management

403

Radionuclide migration studies in soil  

International Nuclear Information System (INIS)

In this work a brief description about retention and migration parameters of radionuclides in soil, including main methods to determine the distribution coefficient (K) are given. Some of several factors that can act on the migration are also mentioned. (author)

404

Mobility of radionuclides in soil  

International Nuclear Information System (INIS)

Recent public interest in nuclear power production and waste disposal has led to increased awareness and concern about the biological hazards of radionuclide cycling in soil. Various radionuclides found in soils are shown and can be seen to originate from numerous sources including: radioisotopes formed during earth genesis, cosmic irradiation, fallout from atmospheric testing, uranium mill tailings, phosphate mill wastes, nuclear and coal fired power plants, defense activities, medical, industrial and research use. The objectives of this review are to summarize the factors that affect radionuclide mobility in soil, including adsorption-desorption, precipitation-dissolution reactions for liquid phase radionuclides as well as the transport of gaseous radionuclides in soils. Areas where more information is needed are also discussed. The mobility of selected radionuclides including isotopes of Sr, Cs, Co, Tc, I, Se, Pu, Am, Np, and Rn are discussed in additional detail. Two brief examples of waste management systems to control radionuclide mobility are presented

405

Death of Micrococcus luteus in Soil  

OpenAIRE

Micrococcus luteus cells died relatively quickly when they were added to natural soil. The results were similar for soil in nature and as soil samples in the laboratory. The cells died more quickly when nutrients were added to the soil. Those cells that survived soil residence exhibited a temporary lengthening of the time required for colonial growth and pigment formation on laboratory media. They had not gained increased survival capability, however. This was evident when they were retested ...

Casida, L. E.

1980-01-01

406

Agriculture Canada Central Saskatchewan Vector Soils Data  

Science.gov (United States)

This data set consists of GIS layers that describe the soils of the BOREAS SSA. These original data layers were submitted as vector data in ARC/INFO EXPORT format. These data also include the soil name and soil layer files, which provide additional information about the soils. There are three sets of attributes that include information on the primary, secondary, and tertiary soil type within each polygon. Thus, there is a total of nine main attributes in this data set.

Knapp, David; Hall, Forrest G. (Editor); Rostad, Harold

2000-01-01

407

Soil parameter effects on steamdisinfestation efficiency  

OpenAIRE

Steam soil disinfestation is now reconsidered by many growers for its efficacy in soil borne pathogens, nematodes and weed seeds control, ensuring a low ecological impact. At present time, some disinfestation machines and tractor implements, which supply steam to the soil using different distribution systems and devices, are commercially available. Soil conditions play an important role and can significantly influence the efficacy of the treatment, changing thermal properties of soil and i...

Piccarolo, Pietro; Tortia, Cristina; Gay, Paolo; Ricauda Aimonino, Davide

2008-01-01

408

Soil Ecosystem Management in Birdlime Utilization  

Directory of Open Access Journals (Sweden)

Full Text Available The article deals with the management of material composition of the soil ecosystem, offers the technology and the technical solution for biological, inorganic substances and pollutants dispersal, passivation of soil pollutants at the depth of the current anthropogenic illuviation of 3060 cm, works out the device for soil application of substances by rotary inter-soil cultivation providing soil and landscape conditioning.

Mohammed A. Bazgiev

2012-07-01

409

Tropical Volcanic Soils From Flores Island, Indonesia  

OpenAIRE

Soils that are developed intropical region with volcanic parent materials have many unique properties, and high potential for agricultural use.The purpose of this study is to characterize the soils developed on volcanic materials from Flores Island, Indonesia,and to examine if the soils meet the requirements for andic soil properties. Selected five soils profiles developed fromandesitic volcanic materials from Flores Island were studied to determine their properties. They were compared inthei...

Hikmatullah; Kesumo Nugroho

2010-01-01

410

A Field View of Soil - Digging Around  

Science.gov (United States)

In this field activity, students learn about the five soil-forming factors and their influence on soil properties such as moisture, temperature, color and texture. They identify factors such as slope, shade, plants and compaction, and investigate how these factors affect the a soil's appearance and moisture holding ability. This is a learning activity associated with the GLOBE soil investigations and is supported by the Soil chapter of the GLOBE Teachers Guide.

411

Sampling and hydraulic properties of stony soils  

OpenAIRE

Subjects of this thesis were sampling and hydraulic properties of stony soils. Sampling is important to achieve knowledge of soil spatial variability. Soil surveys are generally time-consuming, labour-intensive and costly. This is especially true in stony soils where large numbers of samples are required to obtain a rappresentative sample size, and where sampling efforts are bigger than in non-stony soils. The potential use, of electromagnetic induction scans (EMI) to measure bulk electri...

Pagliarin, Chiara

2009-01-01

412

Soil erosion and agricultural sustainability  

OpenAIRE

Data drawn from a global compilation of studies quantitatively confirm the long-articulated contention that erosion rates from conventionally plowed agricultural fields average 12 orders of magnitude greater than rates of soil production, erosion under native vegetation, and long-term geological erosion. The general equivalence of the latter indicates that, considered globally, hillslope soil production and erosion evolve to balance geologic and climate forcing, whereas conventional plow-b...

Montgomery, David R.

2007-01-01

413

Soil biodiversity for agricultural sustainability  

OpenAIRE

We critically highlight some evidence for the importance of soil biodiversity to sustaining (agro-)ecosystem functioning and explore directions for future research. We first deal with resistance and resilience against abiotic disturbance and stress. There is evidence that soil biodiversity does confer stability to stress and disturbance, but the mechanism is not yet fully understood. It appears to depend on the kind of stress and disturbance and on the combination of stress and disturbance ef...

Brussaard, L.; Ruiter, P. C.; Brown, G. G.

2007-01-01

414

Anthropogenic effects on soil micromycetes  

OpenAIRE

This paper is a synthesis of long-term investigations based on the effect of different authropogenic pollutants (mineral and organic fertilizers, heavy metals, contaminated irrigation water, nitrification inhibitor and detergents) on the dynamics of soil fungi number. The investigations were performed at the Microbiology Department and trial fields of the Faculty of Agronomy in ?a?ak on smonitza and alluvium soils in field and under greenhouse conditions. Maize, wheat, barley and red clover...

?uki? Dragutin A.; Mandi? Leka G.; umanov Vesna; Raketi? Svetlana

2007-01-01

415

Microbiological research of soil bioremediation  

OpenAIRE

Bioremediation is the application of biological processes for the clean up of pollutants present in the environment. The scope of the review encompasses the following subjects: biodegradation of various polymeric and natural origin compounds; the applications of microorganisms to laboratory scale and field scale soil bioremediation, with a focus on petroleum hydrocarbons; bioaugmentation and characterization of microbial communities; the factors affecting soil bioremediation processes includi...

Kale?diene?, Lilija

2009-01-01

416

CAS-1 lunar soil simulant  

Science.gov (United States)

Lunar soil simulant is a geochemical reproduction of lunar regolith, and is needed for lunar science and engineering researches. This paper describes a new lunar soil simulant, CAS-1, prepared by the Chinese Academy of Sciences, to support lunar orbiter, soft-landing mission and sample return missions of Chinas Lunar Exploration Program, which is scheduled for 2004 2020. Such simulants should match the samples returned from the Moon, all collected from the lunar regolith rather than outcrops. The average mineral and chemical composition of lunar soil sample returned from the Apollo 14 mission, which landed on the Fra Mauro Formation, is chosen as the model for the CAS-1 simulant. Source material for this simulant was a low-Ti basaltic scoria dated at 1600 years from the late Quaternary volcanic area in the Changbai Mountains of northeast China. The main minerals of this rock are pyroxene, olivine, and minor plagioclase, and about 20 40% modal glass. The scoria was analyzed by XRF and found to be chemically similar to Apollo 14 lunar sample 14163. It was crushed in an impact mill with a resulting median particle size 85.9 ?m, similar to Apollo soils. Bulk density, shear resistance, complex permittivity, and reflectance spectra were also similar to Apollo 14 soil. We conclude that CAS-1 is an ideal lunar soil simulant for science and engineering research of future lunar exploration program.

Zheng, Yongchun; Wang, Shijie; Ouyang, Ziyuan; Zou, Yongliao; Liu, Jianzhong; Li, Chunlai; Li, Xiongyao; Feng, Junming

2009-02-01

417

The nature of lunar soil  

Science.gov (United States)

Characteristics of lunar soil are examined. The paper includes topics such as lunar soil genesis, particle types, grain size distribution, grain shape distribution, specific gravity, minimum and maximum density, and relative density. Lunar soil, consisting of complex mixtures of mineral fragments, miscellaneous glasses, agglutinates, and lithic fragments, is produced primarily by meteorite impacts. The grain size distributions for soils exposed to meteorite reworking for 100 million yr or more are classified as well-graded silty sands and sandy silts. The specific gravity of submillimeter lunar soil samples varies from 2.9 to 3.24 and individual particles range from 1.0 to greater than 3.32. Differences in specific gravity, intragranular porosity, particle shape, surface texture, and grain arrangements result in wide ranges in minimum and maximum densities. Meteorite impacts cause in situ lunar soil to have a low relative density at the surface which increases rapidly to a very high relative density at depths greater than 10 cm to 20 cm.

Carrier, W., III; Mitchell, J. K.; Mahmood, A.

1973-01-01

418

Brazilian Cerrado soil Actinobacteria ecology.  

Science.gov (United States)

A total of 2152 Actinobacteria strains were isolated from native Cerrado (Brazilian Savannah) soils located in Passos, Luminrias, and Arcos municipalities (Minas Gerais State, Brazil). The soils were characterised for chemical and microbiological analysis. The microbial analysis led to the identification of nine genera (Streptomyces, Arthrobacter, Rhodococcus, Amycolatopsis, Microbacterium, Frankia, Leifsonia, Nakamurella, and Kitasatospora) and 92 distinct species in both seasons studied (rainy and dry). The rainy season produced a high microbial population of all the aforementioned genera. The pH values of the soil samples from the Passos, Luminrias, and Arcos regions varied from 4.1 to 5.5. There were no significant differences in the concentrations of phosphorus, magnesium, and organic matter in the soils among the studied areas. Samples from the Arcos area contained large amounts of aluminium in the rainy season and both hydrogen and aluminium in the rainy and dry seasons. The Ac