Recording Earthen Architecture at the Peruvian Andes: the Case of KUÑO Tambo CHURCH'S Historic Wall Paintings

NASA Astrophysics Data System (ADS)

Percy, K.; Hanley, C.; Santana Quintero, M.; Fai, S.; Ouimet, C.; Cancino, C.; Rainer, L.; Villacorta-Santamato, L.

2013-07-01

According to UNESCO "Earthen architecture is one of the most original and powerful expressions of our ability to create a built environment with readily available resources. It includes a great variety of structures, ranging from mosques, palaces and granaries, to historic city centres, cultural landscapes and archaeological sites" (WHEAP, 2007). This contribution looks at developing effective methods for recording earthen historic structures for their rehabilitation and preservation using the Kuño Tambo church in Peru, which is a Peruvian national historic site that requires serious rehabilitation work, as a case study. This project describes the compilation of an effective metric record of the "state-of-conservation" - "as found" of wall paintings in this important and remote building using a toolbox of different "off-the-shelf" heritage recording techniques. This approach was applied by Carleton Immersive Media Studio (CIMS), as part of the Earthen Architecture Initiative of the Getty Conservation Institute (GCI).

Active and passive electrical and seismic time-lapse monitoring of earthen embankments

NASA Astrophysics Data System (ADS)

Rittgers, Justin Bradley

In this dissertation, I present research involving the application of active and passive geophysical data collection, data assimilation, and inverse modeling for the purpose of earthen embankment infrastructure assessment. Throughout the dissertation, I identify several data characteristics, and several challenges intrinsic to characterization and imaging of earthen embankments and anomalous seepage phenomena, from both a static and time-lapse geophysical monitoring perspective. I begin with the presentation of a field study conducted on a seeping earthen dam, involving static and independent inversions of active tomography data sets, and self-potential modeling of fluid flow within a confined aquifer. Additionally, I present results of active and passive time-lapse geophysical monitoring conducted during two meso-scale laboratory experiments involving the failure and self-healing of embankment filter materials via induced vertical cracking. Identified data signatures and trends, as well as 4D inversion results, are discussed as an underlying motivation for conducting subsequent research. Next, I present a new 4D acoustic emissions source localization algorithm that is applied to passive seismic monitoring data collected during a full-scale embankment failure test. Acoustic emissions localization results are then used to help spatially constrain 4D inversion of collocated self-potential monitoring data. I then turn to time-lapse joint inversion of active tomographic data sets applied to the characterization and monitoring of earthen embankments. Here, I develop a new technique for applying spatiotemporally varying structural joint inversion constraints. The new technique, referred to as Automatic Joint Constraints (AJC), is first demonstrated on a synthetic 2D joint model space, and is then applied to real geophysical monitoring data sets collected during a full-scale earthen embankment piping-failure test. Finally, I discuss some non-technical issues related to

Assessment of earthen levee stability for management and response: A NASA-DHS-California Dept. Water Resources collaboration

NASA Astrophysics Data System (ADS)

An, K.; Jones, C. E.; Bekaert, D. P.; Dudas, J.

2016-12-01

Radar remote sensing of the Sacramento-San Joaquin Delta, the largest estuary in the western U.S. (over 2500 km2), and its levee system provides an opportunity for NASA Applied Science to aid the CA Department of Water Resources (CA-DWR) in monitoring and emergency response. The delta contains over 1,500 km of earthen levees, supports about 2.5 million acres of agricultural land, and serves as a main water supply for 23 million California residents. Many of the reclaimed islands are 10-25 feet below sea level, sit atop compressible peat and organic clay soils, and are surrounded by levees only 1 foot above the once in a century flood elevation threshold. Land subsidence in the delta can be attributed to a variety of factors, including: aerobic oxidation of soils, soil compaction from drainage, wind erosion, anaerobic decomposition, dissolved carbon fluxes, floods, seismic events, and even rodent burrowing. Interferometric Synthetic Aperture Radar (InSAR) is an established technique to measure surface displacements and has been used to map large-scale subsidence. The demonstration of earthen levee monitoring is a recent development that has been greatly furthered by the emergence of new instruments such as NASA's Uninhabited Aerial Vehicle Synthetic Aperture Radar (UAVSAR). UAVSAR is an L-band airborne sensor with high signal-to-noise ratio, repeat flight track accuracy, and has a high spatial resolution (7 x 7 m) that is necessary for detailed levee monitoring. The adaptability of radar instruments in their ability to see through smoke, haze, and clouds during the day or night, is especially relevant during disaster events, when cloud cover or lack of solar illumination inhibits traditional visual surveys of damage. We demonstrate the advantages of combining InSAR with geographic information systems (GIS) datasets in locating subsidence features along critical levee infrastructure in the Delta for 2009-2016. The ability to efficiently locate potential areas of

3. Earthen berm and water control structure used to regulate ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

3. Earthen berm and water control structure used to regulate water flow into adjacent cultivated area - Natomas Ditch System, Blue Ravine Segment, Juncture of Blue Ravine & Green Valley Roads, Folsom, Sacramento County, CA

The use of seismic tomograms for the identification of internal problems with earthen dams and levees

USDA-ARS?s Scientific Manuscript database

According to the National Inventory of dams (NID, 2009), out of the 84,134 dams in the US, more than 87% (73,423) are earthen dams. The majority of these earthen dams are past or approaching their design life expectancy of 50 years. According to the National committee on Levee Safety (NCLS, 2009),...

Geophysical methods for the assessment of earthen dams

USDA-ARS?s Scientific Manuscript database

Dams and levees are an integral part of the fluvial system in watersheds. Their stability is of utmost concern to the Nation and to those directly impacted should failure occur. There are some 88,000 dams and 110,000 miles of levees in the USA. Many of those are earthen embankments and structures su...

Assessment of soil-gas and soil contamination at the Patterson Anti-Tank Range, Fort Gordon, Georgia, 2009-2010

USGS Publications Warehouse

Caldwell, Andral W.; Falls, W. Fred; Guimaraes, Wladmir B.; Ratliff, W. Hagan; Wellborn, John B.; Landmeyer, James E.

2011-01-01

Soil gas and soil were assessed for contaminants at the Patterson Anti-Tank Range at Fort Gordon, Georgia, from October 2009 to September 2010. The assessment included identifying and delineating organic contaminants present in soil-gas samplers from the area estimated to be the Patterson Anti-Tank Range and in the hyporheic zone and floodplain of Brier Creek. This assessment was conducted to provide environmental contamination data to Fort Gordon personnel pursuant to requirements for the Resource Conservation and Recovery Act Part B Hazardous Waste Permit process. Soil-gas samplers in the hyporheic zone and floodplain of Brier Creek contained total petroleum hydrocarbons, benzene, octane, and pentadecane concentrations above method detection levels. All soil-gas samplers within the boundary of the Patterson Anti-Tank Range contained total petroleum hydrocarbons above the method detection level. The highest total petroleum hydrocarbon mass detected was 147.09 micrograms in a soil-gas sampler located near the middle of the site and near the remnants of a manmade earthen mound and trench. The highest toluene mass detected was 1.04 micrograms and was located in the center of the Patterson Anti-Tank Range and coincides with a manmade earthen mound. Some soil-gas samplers installed detected undecane masses greater than the method detection level of 0.04 microgram, with the highest detection of soil-gas undecane mass of 58.64 micrograms collected along the southern boundary of the site. Some soil-gas samplers were installed in areas of high-contaminant mass to assess for explosives and chemical agents. Explosives or chemical agents were not detected above their respective method detection levels for all soil-gas samplers installed.

4. GENERAL VIEW SHOWING EARTHEN BERM AROUND STRUCTURE. NOTE INSTRUMENTATION ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

4. GENERAL VIEW SHOWING EARTHEN BERM AROUND STRUCTURE. NOTE INSTRUMENTATION TRENCH IN FOREGROUND RIGHT; VIEW TO WEST. - Cape Canaveral Air Station, Launch Complex 17, Facility 28401, East end of Lighthouse Road, Cape Canaveral, Brevard County, FL

4. OVERVIEW TO EAST, FROM WEST END OF EARTHEN EMBANKMENT, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

4. OVERVIEW TO EAST, FROM WEST END OF EARTHEN EMBANKMENT, SHOWING DOWNSTREAM FACE OF DAM, AND SPILLWAY FACE IN DISTANCE AT UPPER RIGHT. - Prado Dam, Embankment, Santa Ana River near junction of State Highways 71 & 91, Corona, Riverside County, CA

A Study of Pattern Prediction in the Monitoring Data of Earthen Ruins with the Internet of Things.

PubMed

Xiao, Yun; Wang, Xin; Eshragh, Faezeh; Wang, Xuanhong; Chen, Xiaojiang; Fang, Dingyi

2017-05-11

An understanding of the changes of the rammed earth temperature of earthen ruins is important for protection of such ruins. To predict the rammed earth temperature pattern using the air temperature pattern of the monitoring data of earthen ruins, a pattern prediction method based on interesting pattern mining and correlation, called PPER, is proposed in this paper. PPER first finds the interesting patterns in the air temperature sequence and the rammed earth temperature sequence. To reduce the processing time, two pruning rules and a new data structure based on an R-tree are also proposed. Correlation rules between the air temperature patterns and the rammed earth temperature patterns are then mined. The correlation rules are merged into predictive rules for the rammed earth temperature pattern. Experiments were conducted to show the accuracy of the presented method and the power of the pruning rules. Moreover, the Ming Dynasty Great Wall dataset was used to examine the algorithm, and six predictive rules from the air temperature to rammed earth temperature based on the interesting patterns were obtained, with the average hit rate reaching 89.8%. The PPER and predictive rules will be useful for rammed earth temperature prediction in protection of earthen ruins.

Closing the loop of the soil water retention curve

USGS Publications Warehouse

Lu, Ning; Alsherif, N; Wayllace, Alexandra; Godt, Jonathan W.

2015-01-01

The authors, to their knowledge for the first time, produced two complete principal soil water retention curves (SWRCs) under both positive and negative matric suction regimes. An innovative testing technique combining the transient water release and imbibition method (TRIM) and constant flow method (CFM) was used to identify the principal paths of SWRC in the positive pore-water pressure regime under unsaturated conditions. A negative matric suction of 9.8 kPa is needed to reach full saturation or close the loop of the SWRC for a silty soil. This work pushes the understanding of the interaction of soil and water into new territory by quantifying the boundaries of the SWRC over the entire suction domain, including both wetting and drying conditions that are relevant to field conditions such as slope wetting under heavy rainfall or rapid groundwater table rise in earthen dams or levees.

Performance evaluation of low cost microbial fuel cell fabricated using earthen pot with biotic and abiotic cathode.

PubMed

Behera, Manaswini; Jana, Partha S; Ghangrekar, M M

2010-02-01

An attempt has been made to produce low cost MFC from the commercially available earthen pots in India, without involving any costly membrane. This MFC gave a maximum power output of 16.8 W/m(3) at a Coulombic efficiency (CE) of 31.3% with graphite plate cathode. With stainless steel mesh cathode and KMnO(4) as cathodic electrolyte the power production and CE of 70.48 W/m(3) and 64.5%, respectively, was obtained. The performance of this earthen pot MFC was evaluated with biotic and abiotic cathode. Although, biofilm formation on the cathode is observed to be helpful in enhancing power out put, the thicker biofilm on the cathode showed reduction in power. This MFC demonstrated competitive performance as compared to MFC incorporated with membrane. This low cost MFC, with total production cost of less than 1.0$, as per Indian market, demonstrated its utility as a wastewater treatment and onsite power generation device.

Effects of season on ecological processes in extensive earthen tilapia ponds in Southeastern Brazil.

PubMed

Favaro, E G P; Sipaúba-Tavares, L H; Milstein, A

2015-11-01

In Southeastern Brazil tilapia culture is conducted in extensive and semi-intensive flow-through earthen ponds, being water availability and flow management different in the rainy and dry seasons. In this region lettuce wastes are a potential cheap input for tilapia culture. This study examined the ecological processes developing during the rainy and dry seasons in three extensive flow-through earthen tilapia ponds fertilized with lettuce wastes. Water quality, plankton and sediment parameters were sampled monthly during a year. Factor analysis was used to identify the ecological processes occurring within the ponds and to construct a conceptual graphic model of the pond ecosystem functioning during the rainy and dry seasons. Processes related to nitrogen cycling presented differences between both seasons while processes related to phosphorus cycling did not. Ecological differences among ponds were due to effects of wind protection by surrounding vegetation, organic loading entering, tilapia density and its grazing pressure on zooplankton. Differences in tilapia growth among ponds were related to stocking density and ecological process affecting tilapia food availability and intraspecific competition. Lettuce wastes addition into the ponds did not produce negative effects, thus this practice may be considered a disposal option and a low-cost input source for tilapia, at least at the amounts applied in this study.

Potential use of calcareous mudstones in low hydraulic conductivity earthen barriers for environmental applications.

PubMed

Musso, T B; Francisca, F M; Musso, T B; Musso, T B

2013-01-01

Earthen layers play a significant role in isolating contaminants in the subsurface, controlling the migration of contaminant plumes, and as landfill liners and covers. The physical, chemical and mineralogical properties of three calcareous mudstones from the Jagüel and Roca formations in North Patagonia, Argentina, are evaluated to determine their potential for the construction of liners. These mudstones were deposited in a marine environment in the Upper Cretaceous-Paleocene. The tested specimens mainly comprise silt and clay-sized particles, and their mineralogy is dominated by a smectite/illite mixed layer (70-90% Sm) and calcite in smaller proportion. Powdered mudstone samples have little viscosity and swelling potential when suspended in water. The hydraulic conductivity of compacted mudstones and sand-mudstone mixtures is very low (around 1-3 x 10(-10) m/s) and in good agreement with the expected hydraulic behaviour of compacted earthen layers. This behaviour can be attributed to the large amount of fine particles, high specific surface and the close packing of particles as confirmed by scanning electron microscope analysis. The tested materials also show a high cation exchange capacity (50-70 cmol/kg), indicating a high contaminant retardation capability. The calcareous mudstones show satisfactory mineralogical and chemical properties as well as an adequate hydraulic behaviour, demonstrating the potential use of these materials for the construction of compacted liners for the containment of leachate or as covers in landfills. These findings confirm the potential usage of marine calcareous mudstones as a low-cost geomaterial in environmental engineering projects.

7 CFR 330.302 - Domestic movements of earth (including soil), stone, etc.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 5 2010-01-01 2010-01-01 false Domestic movements of earth (including soil), stone...; GENERAL; PLANT PESTS; SOIL, STONE, AND QUARRY PRODUCTS; GARBAGE Movement of Soil, Stone, And Quarry Products § 330.302 Domestic movements of earth (including soil), stone, etc. The interstate movement from...

7 CFR 330.302 - Domestic movements of earth (including soil), stone, etc.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 7 Agriculture 5 2012-01-01 2012-01-01 false Domestic movements of earth (including soil), stone...; GENERAL; PLANT PESTS; SOIL, STONE, AND QUARRY PRODUCTS; GARBAGE Movement of Soil, Stone, And Quarry Products § 330.302 Domestic movements of earth (including soil), stone, etc. The interstate movement from...

7 CFR 330.302 - Domestic movements of earth (including soil), stone, etc.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 7 Agriculture 5 2011-01-01 2011-01-01 false Domestic movements of earth (including soil), stone...; GENERAL; PLANT PESTS; SOIL, STONE, AND QUARRY PRODUCTS; GARBAGE Movement of Soil, Stone, And Quarry Products § 330.302 Domestic movements of earth (including soil), stone, etc. The interstate movement from...

7 CFR 330.302 - Domestic movements of earth (including soil), stone, etc.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 7 Agriculture 5 2014-01-01 2014-01-01 false Domestic movements of earth (including soil), stone...; GENERAL; PLANT PESTS; SOIL, STONE, AND QUARRY PRODUCTS; GARBAGE Movement of Soil, Stone, And Quarry Products § 330.302 Domestic movements of earth (including soil), stone, etc. The interstate movement from...

7 CFR 330.302 - Domestic movements of earth (including soil), stone, etc.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 7 Agriculture 5 2013-01-01 2013-01-01 false Domestic movements of earth (including soil), stone...; GENERAL; PLANT PESTS; SOIL, STONE, AND QUARRY PRODUCTS; GARBAGE Movement of Soil, Stone, And Quarry Products § 330.302 Domestic movements of earth (including soil), stone, etc. The interstate movement from...

Monitoring earthen dams and levees with ambient seismic noise

NASA Astrophysics Data System (ADS)

Planès, T.; Mooney, M.; Rittgers, J. B.; Kanning, W.; Draganov, D.

2017-12-01

Internal erosion is a major cause of failure of earthen dams and levees and is difficult to detect at an early stage by traditional visual inspection techniques. The passive and non-invasive ambient-noise correlation technique could help detect and locate internal changes taking place within these structures. First, we apply this passive seismic method to monitor a canal embankment model submitted to piping erosion, in laboratory-controlled conditions. We then present the monitoring of a sea levee in the Netherlands. A 150m-long section of the dike shows sandboils in the drainage ditch located downstream of the levee. These sandboils are the sign of concentrated seepage and potential initiation of internal erosion in the structure. Using the ambient-noise correlation technique, we retrieve surface waves propagating along the crest of the dike. Temporal variations of the seismic wave velocity are then computed during the tide cycle. These velocity variations are correlated with local in-situ pore water pressure measurements and are possibly influenced by the presence of concentrated seepage paths.

Water-quality data from an earthen dam site in southern Westchester County, New York, 2015

USGS Publications Warehouse

Chu, Anthony; Noll, Michael L.

2017-10-11

The U.S. Geological Survey, in cooperation with the New York City Department of Environmental Protection, sampled 37 sites in the reservoir area for nutrients, major ions, metals, pesticides and their degradates, volatile organic compounds, temperature, pH, and specific conductance during fall 2015. Data collection was done to characterize the local groundwater-flow system and identify potential sources of seeps from the southern embankment at the Hillview Reservoir. Water-quality samples were collected in accordance with standard U.S. Geological Survey methods at 37 sites in and adjacent to Hillview Reservoir. These 37 sites were sampled to determine (1) baseline water-quality conditions of the saturated, low-permeability sediments that compose the earthen embankment that surrounds the reservoir, (2) water-quality conditions in the southwestern part of the study area in relation to the seeps on the embankment, and (3) temporal variation of water-quality conditions between 2006 and 2015 (not included in this report). The physical parameters and the results of the water-quality analysis from the 37 sites are included in this report and can be downloaded from the U.S. Geological Survey National Water Information System website.

Rice mill wastewater treatment in microbial fuel cells fabricated using proton exchange membrane and earthen pot at different pH.

PubMed

Behera, Manaswini; Jana, Partha S; More, Tanaji T; Ghangrekar, M M

2010-10-01

Performance of microbial fuel cells (MFCs), fabricated using an earthen pot (MFC-1) and a proton exchange membrane (MFC-2), was evaluated while treating rice mill wastewater at feed pH of 8.0, 7.0 and 6.0. A third MFC (MFC-3), fabricated using a proton exchange membrane (PEM), was operated as control without pH adjustment of the acidic raw wastewater. Maximum chemical oxygen demand (COD) removal efficiencies of 96.5% and 92.6% were obtained in MFC-1 and MFC-2, respectively, at feed pH of 8.0. MFC-3 showed maximum COD removal of 87%. The lignin removal was 84%, 79%, and 77% and the phenol removal was 81%, 77%, and 76% in MFC-1, MFC-2, and MFC-3, respectively. Maximum sustainable volumetric power was obtained at feed pH of 8.0, and it was 2.3 W/m(3) and 0.53 W/m(3), with 100 ohm external resistance, in MFC-1 and MFC-2, respectively. The power was lower at lower feed pH. MFC-3 generated lowest volumetric power (0.27 W/m(3)) as compared to MFC-1 and MFC-2. More effective treatment of rice mill wastewater and higher energy recovery was demonstrated by earthen pot MFC as compared to MFC incorporated with PEM. 2010 Elsevier B.V. All rights reserved.

Geophysical investigation of seepage beneath an earthen dam.

PubMed

Ikard, S J; Rittgers, J; Revil, A; Mooney, M A

2015-01-01

A hydrogeophysical survey is performed at small earthen dam that overlies a confined aquifer. The structure of the dam has not shown evidence of anomalous seepage internally or through the foundation prior to the survey. However, the surface topography is mounded in a localized zone 150 m downstream, and groundwater discharges from this zone periodically when the reservoir storage is maximum. We use self-potential and electrical resistivity tomography surveys with seismic refraction tomography to (1) determine what underlying hydrogeologic factors, if any, have contributed to the successful long-term operation of the dam without apparent indicators of anomalous seepage through its core and foundation; and (2) investigate the hydraulic connection between the reservoir and the seepage zone to determine whether there exists a potential for this success to be undermined. Geophysical data are informed by hydraulic and geotechnical borehole data. Seismic refraction tomography is performed to determine the geometry of the phreatic surface. The hydro-stratigraphy is mapped with the resistivity data and groundwater flow patterns are determined with self-potential data. A self-potential model is constructed to represent a perpendicular profile extending out from the maximum cross-section of the dam, and self-potential data are inverted to recover the groundwater velocity field. The groundwater flow pattern through the aquifer is controlled by the bedrock topography and a preferential flow pathway exists beneath the dam. It corresponds to a sandy-gravel layer connecting the reservoir to the downstream seepage zone. © 2014, National Ground Water Association.

29 CFR 780.110 - Operations included in “cultivation and tillage of the soil.”

Code of Federal Regulations, 2014 CFR

2014-07-01

... 29 Labor 3 2014-07-01 2014-07-01 false Operations included in âcultivation and tillage of the soil... FAIR LABOR STANDARDS ACT General Scope of Agriculture Cultivation and Tillage of the Soil § 780.110 Operations included in “cultivation and tillage of the soil.” “Cultivation and tillage of the soil” includes...

29 CFR 780.110 - Operations included in “cultivation and tillage of the soil.”

Code of Federal Regulations, 2010 CFR

2010-07-01

... 29 Labor 3 2010-07-01 2010-07-01 false Operations included in âcultivation and tillage of the soil... FAIR LABOR STANDARDS ACT General Scope of Agriculture Cultivation and Tillage of the Soil § 780.110 Operations included in “cultivation and tillage of the soil.” “Cultivation and tillage of the soil” includes...

29 CFR 780.110 - Operations included in “cultivation and tillage of the soil.”

Code of Federal Regulations, 2012 CFR

2012-07-01

... 29 Labor 3 2012-07-01 2012-07-01 false Operations included in âcultivation and tillage of the soil... FAIR LABOR STANDARDS ACT General Scope of Agriculture Cultivation and Tillage of the Soil § 780.110 Operations included in “cultivation and tillage of the soil.” “Cultivation and tillage of the soil” includes...

29 CFR 780.110 - Operations included in “cultivation and tillage of the soil.”

Code of Federal Regulations, 2013 CFR

2013-07-01

... 29 Labor 3 2013-07-01 2013-07-01 false Operations included in âcultivation and tillage of the soil... FAIR LABOR STANDARDS ACT General Scope of Agriculture Cultivation and Tillage of the Soil § 780.110 Operations included in “cultivation and tillage of the soil.” “Cultivation and tillage of the soil” includes...

29 CFR 780.110 - Operations included in “cultivation and tillage of the soil.”

Code of Federal Regulations, 2011 CFR

2011-07-01

... 29 Labor 3 2011-07-01 2011-07-01 false Operations included in âcultivation and tillage of the soil... FAIR LABOR STANDARDS ACT General Scope of Agriculture Cultivation and Tillage of the Soil § 780.110 Operations included in “cultivation and tillage of the soil.” “Cultivation and tillage of the soil” includes...

Geometric and frequency EMI sounding of estuarine earthen flood defence embankments in Ireland using 1D inversion models

NASA Astrophysics Data System (ADS)

Viganotti, Matteo; Jackson, Ruth; Krahn, Hartmut; Dyer, Mark

2013-05-01

Earthen flood defence embankments are linear structures, raised above the flood plain, that are commonly used as flood defences in rural settings; these are often relatively old structures constructed using locally garnered material and of which little is known in terms of design and construction. Alarmingly, it is generally reported that a number of urban developments have expanded to previously rural areas; hence, acquiring knowledge about the flood defences protecting these areas has risen significantly in the agendas of basin and asset managers. This paper focusses, by reporting two case studies, on electromagnetic induction (EMI) methods that would efficiently complement routine visual inspections and would represent a first step to more detailed investigations. Evaluation of the results is presented by comparison with ERT profiles and intrusive investigation data. The EM data, acquired using a GEM-2 apparatus for frequency sounding and an EM-31 apparatus for geometrical sounding, has been handled using the prototype eGMS software tool, being developed by the eGMS international research consortium; the depth sounding data interpretation was assisted by 1D inversions obtained with the EM1DFM software developed by the University of British Columbia. Although both sounding methods showed some limitations, the models obtained were consistent with ERT models and the techniques were useful screening methods for the identification of areas of interest, such as material interfaces or potential seepage areas, within the embankment structure: 1D modelling improved the rapid assessment of earthen flood defence embankments in an estuarine environment; evidence that EMI sounding could play an important role as a monitoring tool or as a first step towards more detailed investigations.

Capturing strain localization behind a geosynthetic-reinforced soil wall

NASA Astrophysics Data System (ADS)

Lai, Timothy Y.; Borja, Ronaldo I.; Duvernay, Blaise G.; Meehan, Richard L.

2003-04-01

This paper presents the results of finite element (FE) analyses of shear strain localization that occurred in cohesionless soils supported by a geosynthetic-reinforced retaining wall. The innovative aspects of the analyses include capturing of the localized deformation and the accompanying collapse mechanism using a recently developed embedded strong discontinuity model. The case study analysed, reported in previous publications, consists of a 3.5-m tall, full-scale reinforced wall model deforming in plane strain and loaded by surcharge at the surface to failure. Results of the analysis suggest strain localization developing from the toe of the wall and propagating upward to the ground surface, forming a curved failure surface. This is in agreement with a well-documented failure mechanism experienced by the physical wall model showing internal failure surfaces developing behind the wall as a result of the surface loading. Important features of the analyses include mesh sensitivity studies and a comparison of the localization properties predicted by different pre-localization constitutive models, including a family of three-invariant elastoplastic constitutive models appropriate for frictional/dilatant materials. Results of the analysis demonstrate the potential of the enhanced FE method for capturing a collapse mechanism characterized by the presence of a failure, or slip, surface through earthen materials.

Deriving site-specific soil clean-up values for metals and metalloids: Rationale for including protection of soil microbial processes

PubMed Central

Kuperman, Roman G; Siciliano, Steven D; Römbke, Jörg; Oorts, Koen

2014-01-01

Although it is widely recognized that microorganisms are essential for sustaining soil fertility, structure, nutrient cycling, groundwater purification, and other soil functions, soil microbial toxicity data were excluded from the derivation of Ecological Soil Screening Levels (Eco-SSL) in the United States. Among the reasons for such exclusion were claims that microbial toxicity tests were too difficult to interpret because of the high variability of microbial responses, uncertainty regarding the relevance of the various endpoints, and functional redundancy. Since the release of the first draft of the Eco-SSL Guidance document by the US Environmental Protection Agency in 2003, soil microbial toxicity testing and its use in ecological risk assessments have substantially improved. A wide range of standardized and nonstandardized methods became available for testing chemical toxicity to microbial functions in soil. Regulatory frameworks in the European Union and Australia have successfully incorporated microbial toxicity data into the derivation of soil threshold concentrations for ecological risk assessments. This article provides the 3-part rationale for including soil microbial processes in the development of soil clean-up values (SCVs): 1) presenting a brief overview of relevant test methods for assessing microbial functions in soil, 2) examining data sets for Cu, Ni, Zn, and Mo that incorporated soil microbial toxicity data into regulatory frameworks, and 3) offering recommendations on how to integrate the best available science into the method development for deriving site-specific SCVs that account for bioavailability of metals and metalloids in soil. Although the primary focus of this article is on the development of the approach for deriving SCVs for metals and metalloids in the United States, the recommendations provided in this article may also be applicable in other jurisdictions that aim at developing ecological soil threshold values for protection of

Modeling the plant uptake of organic chemicals, including the soil-air-plant pathway.

PubMed

Collins, Chris D; Finnegan, Eilis

2010-02-01

The soil-air-plant pathway is potentially important in the vegetative accumulation of organic pollutants from contaminated soils. While a number of qualitative frameworks exist for the prediction of plant accumulation of organic chemicals by this pathway, there are few quantitative models that incorporate this pathway. The aim of the present study was to produce a model that included this pathway and could quantify its contribution to the total plant contamination for a range of organic pollutants. A new model was developed from three submodels for the processes controlling plant contamination via this pathway: aerial deposition, soil volatilization, and systemic translocation. Using the combined model, the soil-air-plant pathway was predicted to account for a significant proportion of the total shoot contamination for those compounds with log K(OA) > 9 and log K(AW) < -3. For those pollutants with log K(OA) < 9 and log K(AW) > -3 there was a higher deposition of pollutant via the soil-air-plant pathway than for those chemicals with log K(OA) > 9 and log K(AW) < -3, but this was an insignificant proportion of the total shoot contamination because of the higher mobility of these compounds via the soil-root-shoot pathway. The incorporation of the soil-air-plant pathway into the plant uptake model did not significantly improve the prediction of the contamination of vegetation from polluted soils when compared across a range of studies. This was a result of the high variability between the experimental studies where the bioconcentration factors varied by 2 orders of magnitude at an equivalent log K(OA). One potential reason for this is the background air concentration of the pollutants under study. It was found background air concentrations would dominate those from soil volatilization in many situations unless there was a soil hot spot of contamination, i.e., >100 mg kg(-1).

26 CFR 1.175-4 - Definition of “land used in farming.”

Code of Federal Regulations, 2014 CFR

2014-04-01

... before or at the same time as, the taxpayer makes the expenditures for soil or water conservation or for... land is idle because of the season, A makes certain soil and water conservation expenditures on this..., construct earthen terraces and ponds, and make other soil and water conservation expenditures. The land is...

26 CFR 1.175-4 - Definition of “land used in farming.”

Code of Federal Regulations, 2011 CFR

2011-04-01

... before or at the same time as, the taxpayer makes the expenditures for soil or water conservation or for... land is idle because of the season, A makes certain soil and water conservation expenditures on this..., construct earthen terraces and ponds, and make other soil and water conservation expenditures. The land is...

26 CFR 1.175-4 - Definition of “land used in farming.”

Code of Federal Regulations, 2013 CFR

2013-04-01

... before or at the same time as, the taxpayer makes the expenditures for soil or water conservation or for... land is idle because of the season, A makes certain soil and water conservation expenditures on this..., construct earthen terraces and ponds, and make other soil and water conservation expenditures. The land is...

26 CFR 1.175-4 - Definition of “land used in farming.”

Code of Federal Regulations, 2012 CFR

2012-04-01

... before or at the same time as, the taxpayer makes the expenditures for soil or water conservation or for... land is idle because of the season, A makes certain soil and water conservation expenditures on this..., construct earthen terraces and ponds, and make other soil and water conservation expenditures. The land is...

4-D imaging of seepage in earthen embankments with time-lapse inversion of self-potential data constrained by acoustic emissions localization

NASA Astrophysics Data System (ADS)

Rittgers, J. B.; Revil, A.; Planes, T.; Mooney, M. A.; Koelewijn, A. R.

2015-02-01

New methods are required to combine the information contained in the passive electrical and seismic signals to detect, localize and monitor hydromechanical disturbances in porous media. We propose a field experiment showing how passive seismic and electrical data can be combined together to detect a preferential flow path associated with internal erosion in a Earth dam. Continuous passive seismic and electrical (self-potential) monitoring data were recorded during a 7-d full-scale levee (earthen embankment) failure test, conducted in Booneschans, Netherlands in 2012. Spatially coherent acoustic emissions events and the development of a self-potential anomaly, associated with induced concentrated seepage and internal erosion phenomena, were identified and imaged near the downstream toe of the embankment, in an area that subsequently developed a series of concentrated water flows and sand boils, and where liquefaction of the embankment toe eventually developed. We present a new 4-D grid-search algorithm for acoustic emissions localization in both time and space, and the application of the localization results to add spatially varying constraints to time-lapse 3-D modelling of self-potential data in the terms of source current localization. Seismic signal localization results are utilized to build a set of time-invariant yet spatially varying model weights used for the inversion of the self-potential data. Results from the combination of these two passive techniques show results that are more consistent in terms of focused ground water flow with respect to visual observation on the embankment. This approach to geophysical monitoring of earthen embankments provides an improved approach for early detection and imaging of the development of embankment defects associated with concentrated seepage and internal erosion phenomena. The same approach can be used to detect various types of hydromechanical disturbances at larger scales.

Laboratory study on metal attenuation capacity of fine grained soil near ash pond site.

PubMed

Ghosh, Sudipta; Mukherjee, Somnath; Sarkar, Sujoy; Kumar, Sunil

2008-10-01

Waste settling tanks of earthen containment nature are common in India for disposal of solid waste in slurry form. For a large pond system, e.g. ash slurry disposal tank of coal base thermal power plant, leachate generation and its migration pose a serious problem. A natural attenuation of controlling the migratory leachate is to use locally available clay material as lining system due to the adsorption properties of soil for reducing some metallic ions. The present investigation was carried out to explore the Ni2+ and Cr6+ removal capacity of surrounding soil of the ash pond site of Super Thermal Power Plant in West Bengal, India through some laboratory scale and field studies. The soil and water samples collected from the site showed the existence of Ni2+ and Cr6+ in excess to permissible limit. A two-dimensional adsorption behaviour of these pollutants through soil was assessed. The results showed that more than 80% of nickel and 72% of chromium were found to be sorbed by the soil corresponding to initial concentrations of two ions, i.e. 1.366 mg/L and 0.76 mg/L respectively. The batch adsorption data are tested Langmuir and Freundlich isotherm models and found reasonably fit. Breakthrough adsorption study uptake also showed a good adsorption capacity of the soil. The experimental results found to fit well with the existing two dimensional (2D) mathematical models as proposed by Fetter (1999).

Environmental monitoring of a Sardinian earthen dwelling during the summer season

NASA Astrophysics Data System (ADS)

Desogus, G.; Di Benedetto, S.; Grassi, W.; Testi, D.

2014-11-01

Increasing interest in earth architecture has led to the development of new international norms regarding these structures. Although Italy has no specific legislation for this building type, both national laws for the safeguard of rural architecture and regional norms regarding the conservation of historical centers have considerably slowed down the pace of their destruction. This is particularly true for Sardinia, which maintains a conspicuous heritage of "raw earth" architecture, mostly in the old town centers of the Campidano plain and in its adjacent valley. Due to the current legislation on energy efficiency in buildings, it has become essential - particularly for the Sardinian region - to define guidelines for the improvement of energy efficiency for this existing building heritage and identify the best parameters for their energetic classification. Currently, these constructions are heavily penalized by the gap that persists between the requirements of current energy balance evaluations, calculated upon heating and domestic hot water energy demands, and the actual year-round energy performance, which also includes the summer season. Moreover, this building type has a low lifecycle environmental impact, but this aspect is not properly "rewarded" by Italian regulations. The study proposed herein firstly took into account the simulation of the thermal transient characteristics of the adobe wall (brick made of clay, earth and straw, forged with wooden molds and sun dried). Analytical calculations were performed using a transient model, assuming sinusoidal behavior of all the parameters acting on the system. The results showed a high thermal inertia of the material and a good ability in dampening the external thermal wave. Next, we conducted an internal and external environmental monitoring of an existing earthen residential building in Sardinia ("Casa Mancosu", Serramanna, VS), which provided the experimental data for the evaluation of the whole building thermo

Forest soils bibliography for the North-Central Region (including subject matter index through 1972).

Treesearch

Willard H. Carmean

1973-01-01

Includes 793 publications dealing with forest soils in the North-Central States (Minnesota, Wisconsin, Michigan, Iowa, Missouri, Illinois, and Indiana); Ohio; and the Northern Plains States (Kansas, Nebraska, and the Dakotas). Includes some publications from other regions considered applicable to conditions in the North-Central Region.

Macroalgal biomonitors of trace metal contamination in acid sulfate soil aquaculture ponds.

PubMed

Gosavi, K; Sammut, J; Gifford, S; Jankowski, J

2004-05-25

Earthen shrimp aquaculture ponds are often impacted by acid sulfate soils (ASS), typically resulting in increased disease and mortality of cultured organisms. Production losses have been attributed to either low pH or to elevated concentrations of toxic metals, both direct products of pyrite oxidation in ASS. The standard farm management practice to minimise effects of pyrite oxidation is to maintain pH of pond waters above 5, based on the assumption that dissolved metal bioavailability is negligible at this pH. This study aimed to test the validity of this assumption, and therefore elucidate a possible role of toxic heavy metals in observed decreases in farm productivity. Metal bioaccumulation in four genera of macroalgae, Ulva sp., Enteromorpha sp., Cladophora sp. and Chaetomorpha sp., sampled from ASS-affected shrimp aquaculture ponds were measured using inductively coupled plasma-optical emission spectroscopy (ICP-OES) to assess the relative bioavailability of dissolved metals within the system. Results showed that all four genera of macroalgae accumulated appreciable quantities of Fe, Al, Zn, Cd, Cu, As and Pb. Iron and Al, the most common metals mobilised from ASS, were both accumulated in all algal genera to concentrations three orders of magnitude greater than all other metals analysed. These findings indicate that dissolved heavy metals are indeed bioavailable within the aquaculture pond system. A literature search of heavy metal bioaccumulation by these algal genera revealed concentrations recorded in this study are comparable to highly contaminated environments, such as those exposed to urban, industrial and mining pollution. The results of this study indicate that dissolved metal bioavailability in many earthen shrimp aquaculture ponds may be higher than previously thought.

Finite element modeling of contaminant transport in soils including the effect of chemical reactions.

PubMed

Javadi, A A; Al-Najjar, M M

2007-05-17

The movement of chemicals through soils to the groundwater is a major cause of degradation of water resources. In many cases, serious human and stock health implications are associated with this form of pollution. Recent studies have shown that the current models and methods are not able to adequately describe the leaching of nutrients through soils, often underestimating the risk of groundwater contamination by surface-applied chemicals, and overestimating the concentration of resident solutes. Furthermore, the effect of chemical reactions on the fate and transport of contaminants is not included in many of the existing numerical models for contaminant transport. In this paper a numerical model is presented for simulation of the flow of water and air and contaminant transport through unsaturated soils with the main focus being on the effects of chemical reactions. The governing equations of miscible contaminant transport including advection, dispersion-diffusion and adsorption effects together with the effect of chemical reactions are presented. The mathematical framework and the numerical implementation of the model are described in detail. The model is validated by application to a number of test cases from the literature and is then applied to the simulation of a physical model test involving transport of contaminants in a block of soil with particular reference to the effects of chemical reactions. Comparison of the results of the numerical model with the experimental results shows that the model is capable of predicting the effects of chemical reactions with very high accuracy. The importance of consideration of the effects of chemical reactions is highlighted.

A physically-based method for predicting peak discharge of floods caused by failure of natural and constructed earthen dams

USGS Publications Warehouse

Walder, J.S.; O'Connor, J. E.; Costa, J.E.; ,

1997-01-01

We analyse a simple, physically-based model of breach formation in natural and constructed earthen dams to elucidate the principal factors controlling the flood hydrograph at the breach. Formation of the breach, which is assumed trapezoidal in cross-section, is parameterized by the mean rate of downcutting, k, the value of which is constrained by observations. A dimensionless formulation of the model leads to the prediction that the breach hydrograph depends upon lake shape, the ratio r of breach width to depth, the side slope ?? of the breach, and the parameter ?? = (V.D3)(k/???gD), where V = lake volume, D = lake depth, and g is the acceleration due to gravity. Calculations show that peak discharge Qp depends weakly on lake shape r and ??, but strongly on ??, which is the product of a dimensionless lake volume and a dimensionless erosion rate. Qp(??) takes asymptotically distinct forms depending on whether < ??? 1 or < ??? 1. Theoretical predictions agree well with data from dam failures for which k could be reasonably estimated. The analysis provides a rapid and in many cases graphical way to estimate plausible values of Qp at the breach.We analyze a simple, physically-based model of breach formation in natural and constructed earthen dams to elucidate the principal factors controlling the flood hydrograph at the breach. Formation of the breach, which is assumed trapezoidal in cross-section, is parameterized by the mean rate of downcutting, k, the value of which is constrained by observations. A dimensionless formulation of the model leads to the prediction that the breach hydrograph depends upon lake shape, the ratio r of breach width to depth, the side slope ?? of the breach, and the parameter ?? = (V/D3)(k/???gD), where V = lake volume, D = lake depth, and g is the acceleration due to gravity. Calculations show that peak discharge Qp depends weakly on lake shape r and ??, but strongly on ??, which is the product of a dimensionless lake volume and a

Multi-layer waste containment barrier

DOEpatents

Smith, Ann Marie; Gardner, Bradley M.; Nickelson, David F.

1999-01-01

An apparatus for constructing an underground containment barrier for containing an in-situ portion of earth. The apparatus includes an excavating device for simultaneously (i) excavating earthen material from beside the in-situ portion of earth without removing the in-situ portion and thereby forming an open side trench defined by opposing earthen sidewalls, and (ii) excavating earthen material from beneath the in-situ portion of earth without removing the in-situ portion and thereby forming a generally horizontal underground trench beneath the in-situ portion defined by opposing earthen sidewalls. The apparatus further includes a barrier-forming device attached to the excavating device for simultaneously forming a side barrier within the open trench and a generally horizontal, multi-layer barrier within the generally horizontal trench. The multi-layer barrier includes at least a first layer and a second layer.

Controls on the breach geometry and flood hydrograph during overtopping of non-cohesive earthen dams

USGS Publications Warehouse

Walder, Joseph S.; Iverson, Richard M.; Godt, Jonathan W.; Logan, Matthew; Solovitz, Stephen A.

2015-01-01

Overtopping failure of non-cohesive earthen dams was investigated in 13 large-scale experiments with dams built of compacted, damp, fine-grained sand. Breaching was initiated by cutting a notch across the dam crest and allowing water escaping from a finite upstream reservoir to form its own channel. The channel developed a stepped profile, and upstream migration of the steps, which coalesced into a headcut, led to the establishment of hydraulic control (critical flow) at the channel head, or breach crest, an arcuate erosional feature that functions hydraulically as a weir. Novel photogrammetric methods, along with underwater videography, revealed that the retreating headcut maintained a slope near the angle of friction of the sand, while the cross section at the breach crest maintained a geometrically similar shape through time. That cross-sectional shape was nearly unaffected by slope failures, contrary to the assumption in many models of dam breaching. Flood hydrographs were quite reproducible--for sets of dams ranging in height from 0.55 m to 0.98 m--when the time datum was chosen as the time that the migrating headcut intersected the breach crest. Peak discharge increased almost linearly as a function of initial dam height. Early-time variability between flood hydrographs for nominally identical dams is probably a reflection of subtle experiment-to-experiment differences in groundwater hydrology and the interaction between surface water and groundwater.

Development of a smear proof horizontal and vertical permeability probe.

DOT National Transportation Integrated Search

2013-01-01

Permeability is a measure of how well a porous medium conducts a fluid. For water, this property is called hydraulic conductivity, and it is important for projects that depend on properties of soil and strata, such as earthen dams, retention ponds, d...

Development of a smear proof horizontal and vertical permeability probe : [technical summary].

DOT National Transportation Integrated Search

2013-01-01

Permeability is a measure of how well a porous medium conducts a fluid. For water, this property is called hydraulic conductivity, and it is important for projects that depend on properties of soil and strata, such as earthen dams, retention ponds, d...

Floodplain restoration with flood control: fish habitat value of levee borrow pits

USDA-ARS?s Scientific Manuscript database

Earthen flood control levees are often built using soil excavated from borrow pits lying parallel to and riverward of the finished levee. After construction, these pits can provide valuable floodplain habitats, and their value is well established along corridors of larger rivers. However, levee bo...

Spatial distribution of soil-transmitted helminths, including Strongyloides stercoralis, among children in Zanzibar.

PubMed

Knopp, Stefanie; Mohammed, Khalfan A; Simba Khamis, I; Mgeni, Ali F; Stothard, J Russell; Rollinson, David; Marti, Hanspeter; Utzinger, Jürg

2008-11-01

A programme periodically distributing anthelminthic drugs to school-aged children for the control of soiltransmitted helminthiasis was launched in Zanzibar in the early 1990s. We investigated the spatial distribution of soiltransmitted helminth infections, including Strongyloides stercoralis, in 336 children from six districts in Unguja, Zanzibar, in 2007. One stool sample per child was examined with the Kato-Katz, Koga agar plate and Baermann methods. The point prevalence of the different helminth infections was compared to the geological characteristics of the study sites. The observed prevalences for Trichuris trichiura, Ascaris lumbricoides, hookworm and S. stercoralis were 35.5%, 12.2%, 11.9% and 2.2%, respectively, with considerable spatial heterogeneity. Whilst T. trichiura and hookworm infections were found in all six districts, no A. lumbricoides infections were recorded in the urban setting and only a low prevalence (2.2%) was observed in the South district. S. stercoralis infections were found in four districts with the highest prevalence (4.0%) in the West district. The prevalence of infection with any soil-transmitted helminth was highest in the North A district (69.6%) and lowest in the urban setting (22.4%). A. lumbricoides, hookworm and, with the exception of the North B district, S. stercoralis infections were observed to be more prevalent in the settings north of Zanzibar Town, which are characterized by alluvial clayey soils, moist forest regions and a higher precipitation. After a decade of large-scale administration of anthelminthic drugs, the prevalence of soil-transmitted helminth infections across Unguja is still considerable. Hence, additional measures, such as improving access to adequate sanitation and clean water and continued health education, are warranted to successfully control soil-transmitted helminthiasis in Zanzibar.

A review of soil cadmium contamination in China including a health risk assessment.

PubMed

Wang, Lin; Cui, Xiangfen; Cheng, Hongguang; Chen, Fei; Wang, Jiantong; Zhao, Xinyi; Lin, Chunye; Pu, Xiao

2015-11-01

Cadmium (Cd) is one of the most serious soil contaminants in China, and it poses an increasing risk to human health as large amounts of Cd are emitted into the environment. However, knowledge about soil Cd concentrations and the human health risks of these concentrations at a national scale is limited. In this study, we conducted a review of 190 articles about soil Cd concentrations during 2001 to 2010. The study involved 146 cities in China, and we quantified the risks to human health according to different regions. The results showed that elevated Cd levels were present compared to the background value of soil in 1990, and the soil Cd concentrations in the Guangxi province exceeded even the class III Soil Environmental Quality standard, which is the limit for the normal growth of plants. The Chinese soil Cd concentrations ranged from 0.003 mg kg(-1) to 9.57 mg kg(-1). The soil Cd concentrations had the following trend: northwest > southwest > south central > east > northeast > north. The sources of soil Cd are mainly from smelting, mining, waste disposal, fertilizer and pesticide application, and vehicle exhaust, etc. but differentiated in various regions. The soil Cd contamination in urban areas was more serious than contamination in the agricultural areas. Currently, there is no significant non-carcinogenic risk in any of the provinces. Regarding the different exposure pathways, the dermal pathway is the primary source of soil Cd exposure, and the risk associated with this pathway is generally hundreds of times higher than the risk for an ingestion pathway. For most of the provinces, the health risk to the urban population was higher than the risk to the rural population. For each population, the carcinogenic risk was less than 10(-6) in most of the provinces, except for the urban population in the Hunan province. If the other exposure pathways are fully considered, then the people in these areas may have a higher carcinogenic risk. This

Two Gonostomatid Ciliates from the Soil of Lombardia, Italy; including Note on the Soil Mapping Project.

PubMed

Bharti, Daizy; Kumar, Santosh; La Terza, Antonietta

2015-01-01

Two gonostomatid ciliates, Gonostomum paronense n. sp. and G. strenuum, isolated from the soil sample of paddy field, Lombardia, Italy, were investigated using live observation and protargol impregnation. Gonostomum paronense n. sp. is mainly characterized by a tailed body, frontoventral cirri arranged in pairs, and presence of pretransverse and transverse cirri. Morphologically and morphometrically, the new species is similar to Gonostomum namibiense in having a tailed body and frontoventral cirral pairs; however, it differs mainly in the number of frontoventral cirral pairs (seven vs. three). Phylogenetic analyses based on the SSU rDNA sequences show that the new species is more closely related to G. namibiense than to G. strenuum, supporting the morphological classification based on the cirral pattern and the tailed body. However, due to the poor nodal support and absence of gene sequence of the type species Gonostomum, a more robust phylogeny of this group still remains unresolved. The biometric data of the Italian population of Gonostomum strenuum overlap with those from other known populations. Both species were collected from the industrial area of Parona, in the framework of the "Soil Mapping, Lombardia" project in which, for the first time in Italy, soil ciliates were used as bioindicators of soil quality. © 2015 The Author(s) Journal of Eukaryotic Microbiology © 2015 International Society of Protistologists.

Geophysical and hydrologic analysis of an earthen dam site in southern Westchester County, New York

USGS Publications Warehouse

Chu, Anthony; Stumm, Frederick; Joesten, Peter K.; Noll, Michael L.

2013-01-01

Ninety percent of the drinking water for New York City passes through the Hillview Reservoir facility in the City of Yonkers, Westchester County, New York. In the past, several seeps located downslope from the reservoir have flowed out from the side of the steepest slope at the southern end of the earthen embankment. One seep that has been flowing continuously was discovered during an inspection of the embankment in 1999. Efforts were made in 2001 to locate the potential sources of the continuous flowing seep. In 2005, the U.S. Geological Survey, in cooperation with the New York City Department of Environmental Protection, began a cooperative study to investigate the relevant hydrogeologic framework to characterize the local groundwater-flow system and to determine possible sources of the seeps. The two agencies used hydrologic and surface geophysical techniques to assess the earthen embankment of the Hillview Reservoir. Between April 1, 2005 and March 1, 2008, water levels were measured manually each month at 46 wells surrounding the reservoir, and flow was measured monthly at three of the five seeps on the embankment. Water levels were measured hourly in the East Basin of the reservoir, at 24 of 46 wells, and discharge was measured hourly at two of the five seeps. Slug tests were performed at 16 wells to determine the hydraulic conductivity of the geologic material surrounding the screened zone. Estimated hydraulic conductivities for 25 wells on the southern embankment ranged from 0.0063 to 1.2 feet per day and averaged 0.17 foot per day. The two-dimensional resistivity surveys indicate a subsurface mound of electrically conductive material (low-resistivity zone) beneath the terrace area (top of dam) surrounding the reservoir with a distinct elevation increase closer to the crest. Two-dimensional shear wave velocity surveys indicate a similar structure of the high shear wave velocity materials (high-velocity zone), increasing in elevation toward the crest and

How do temperature and rainfall affect nitrous oxide emissions from open-lot beef cattle feedyard pens?

USDA-ARS?s Scientific Manuscript database

Temperature is a primary factor affecting greenhouse gas (GHG) emissions from agricultural soils, but little is known about how temperature affects nitrous oxide (N2O) emissions from manure. The majority of grain-fed cattle in the Texas Panhandle are finished in large, earthen-surfaced, open-lot fee...

A physically-based method for predicting peak discharge of floods caused by failure of natural and constructed earthen dams

USGS Publications Warehouse

Walder, J.S.

1997-01-01

We analyse a simple, physically-based model of breach formation in natural and constructed earthen dams to elucidate the principal factors controlling the flood hydrograph at the breach. Formation of the breach, which is assumed trapezoidal in cross-section, is parameterized by the mean rate of downcutting, k, the value of which is constrained by observations. A dimensionless formulation of the model leads to the prediction that the breach hydrograph depends upon lake shape, the ratio r of breach width to depth, the side slope ?? of the breach, and the parameter ?? = (V/ D3)(k/???gD), where V = lake volume, D = lake depth, and g is the acceleration due to gravity. Calculations show that peak discharge Qp depends weakly on lake shape r and ??, but strongly on ??, which is the product of a dimensionless lake volume and a dimensionless erosion rate. Qp(??) takes asymptotically distinct forms depending on whether ?? > 1. Theoretical predictions agree well with data from dam failures for which k could be reasonably estimated. The analysis provides a rapid and in many cases graphical way to estimate plausible values of Qp at the breach.

Downscaling soil moisture over regions that include multiple coarse-resolution grid cells

USDA-ARS?s Scientific Manuscript database

Many applications require soil moisture estimates over large spatial extents (30-300 km) and at fine-resolutions (10-30 m). Remote-sensing methods can provide soil moisture estimates over very large spatial extents (continental to global) at coarse resolutions (10-40 km), but their output must be d...

Development and application of a conceptual hydrologic model to predict soil salinity within modern Tunisian oases

NASA Astrophysics Data System (ADS)

Askri, Brahim; Bouhlila, Rachida; Job, Jean Olivier

2010-01-01

SummaryIn modern oases situated in the south of Tunisia, secondary salination of irrigated lands is a crucial problem. The visible salt deposits and soil salination processes are the consequence of several factors including the excessive use of saline irrigation water, seepage from earthen canal systems, inefficient irrigation practices and inadequate drainage. Understanding the mechanism of the secondary salination is of interest in order to maintain existing oases, and thus ensure the sustainability of date production in this part of the country. Therefore, a conceptual, daily, semi-distributed hydrologic model (OASIS_MOD) was developed to analyse the impact of irrigation management on the water table fluctuation, soil salinity and drain discharge, and to evaluate measures to control salinity within an oasis ecosystem. The basic processes incorporated in the model are irrigation, infiltration, percolation to the shallow groundwater, soil evaporation, crop transpiration, groundwater flow, capillary rise flux, and drain discharge. OASIS_MOD was tested with data collected in a parcel of farmland situated in the Segdoud oasis, in the south-west of Tunisia. The calibration results showed that groundwater levels were simulated with acceptable accuracy, since the differences between the simulated and measured values are less than 0.22 m. However, the model under-predicted some water table peaks when irrigation occurs due to inconsistencies in the irrigation water data. The validation results showed that deviations between observed and simulated groundwater levels have increased to about 0.5 m due to under-estimation of groundwater inflow from an upstream palm plantation. A long-term simulation scenario revealed that the soil salinity and groundwater level have three types of variability in time: a daily variability due to irrigation practices, seasonal fluctuation due to climatic conditions and annual variability explained by the increase in cultivated areas. The

The complexities of discussing soil vapor extraction techniques with non-scientists

USDA-ARS?s Scientific Manuscript database

The Centre County Kepone Site is approximately 32.2 acres on which a chemical manufacturing plant and a portion of the Spring Creek watershed are located. Kepone and mirex, were custom manufactured between 1959 and 1974. Earthen lagoons were used to manage onsite waste disposal. Concrete lagoons w...

Earthen embankment breaching

USDA-ARS?s Scientific Manuscript database

A large number of embankment structures, including dams, levees, dikes, and barriers, have been built by humans. These structures play a very important role in flood defense, while many are also used for water supply, power generation, transportation, sediment retention, etc. Since these structure...

Mars on Earth: Analog basaltic soils and particulates from Lonar Crater, India, include Deccan soil, shocked soil, reworked lithic and glassy ejecta, and both shocked and unshocked baked zones

NASA Astrophysics Data System (ADS)

Wright, S. P.

2017-12-01

"There is no perfect analog for Mars on Earth" [first line of Hipkin et al. (2013) Icarus, 261-267]. However, fieldwork and corresponding sample analyses from laboratory instrumentation (to proxy field instruments) has resulted in the finding of unique analog materials that suggest that detailed investigations of Lonar Crater, India would be beneficial to the goals of the Mars Program. These are briefly described below as Analog Processes, Materials, and Fieldwork. Analog Processes: The geologic history of Lonar Crater emulates localities on Mars with 1.) flood basaltic volcanism with interlayer development of 2.) baked zones or "boles" and 3.) soil formation. Of six flows, the lower three are aqueously altered by groundwater to produce a range of 4.) alteration products described below. The impact event 570 ka produced a range of 5.) impactites including shocked baked zones, shocked soils, and altered basalt shocked to a range of shock pressures [Kieffer et al., 1976]. Analog Materials: 65 Ma Deccan basalt contains augite and labradorite. Baked zones are higher in hematite and other iron oxides. Soil consists of calcite and organic matter. Several basalts with secondary alteration are listed here and these mirror alteration on Mars: hematite, chlorite, serpentine, zeolite, and palagonite, with varying combinations of these with primary igneous minerals. All of these materials (#1 through 4 above) are shocked to a range of shocked pressures to produce maskelynite, flowing plagioclase glass, vesiculated plagioclase glass, and complete impact melts. Shocked soils contain schlieren calcite amidst comminuted grains of augite, labradorite, and these glasses. Shocked baked zones unsurprisingly have a petrographic texture similar to hornfels, another product of contact metamorphism. Analog Fieldwork: The ejecta consists of two layers: 8 m of lithic breccia with unshocked and fractured basalts under a 1 m suevite consisting of all ranges of shock pressure described above

Application of the TDR technique for the detection of changes in the internal structure of an earthen flood levee

NASA Astrophysics Data System (ADS)

Janik, Grzegorz; Dawid, Małgorzata; Walczak, Amadeusz; Słowińska-Osypiuk, Joanna; Skierucha, Wojciech; Wilczek, Andrzej; Daniel, Anna

2017-03-01

Failures of earthen flood protection structures cause enormous material loss. Despite this, in the majority these are structures that were built decades ago. As an example, in Poland, the time of operation of approximately three quarters of existing levees and embankments is over 40 years. A similar situation exists in many other European countries. In the period 1998-2009 the economic losses caused by floods amounted to over 60 thousand million Euro. This accounts for approximately one third of the total losses caused by environmental factors. Ruptures of embankments or levees occur as a result of long-lasting elevated water levels in rivers, and such events are always preceded by changes in their internal structure. Such changes cannot be detected from the outside. This paper presents a new method, never used before, for the determination of changes in the internal structure of the body of a levee. The dynamics of the displacements is described by means of new mathematical formulae. The input data necessary for their application include the dynamics of changes in the value of volumetric moisture that is measured with a freely selected short time step by means of the time-domain-reflectrometry technique. The formulae were created on the basis of hitherto unnoticed and uninterpreted drops in moisture a moment before and a moment after the saturation of inner spaces of the levee body. The results obtained from calculations were compared with data from measurements on a physical model of a levee. The settlement values calculated using the method proposed are convergent with those of the true settlement. The maximum relative error was as low as 19%. The method proposed permits the location of changes in the internal structure of a levee before its rupture. Its application is the main component of a system of early warning against floods.

Radon and thoron inhalation doses in dwellings with earthen architecture: Comparison of measurement methods.

PubMed

Meisenberg, Oliver; Mishra, Rosaline; Joshi, Manish; Gierl, Stefanie; Rout, Rajeswari; Guo, Lu; Agarwal, Tarun; Kanse, Sandeep; Irlinger, Josef; Sapra, Balvinder K; Tschiersch, Jochen

2017-02-01

The radioactive noble gas radon ( 222 Rn) and its decay products have been considered a health risk in the indoor environment for many years because of their contribution to the radiation dose of the lungs. The radioisotope thoron ( 220 Rn) and its decay products came into focus of being a health risk only recently. The reason for this is its short half-life, so only building material can become a significant source for indoor thoron. In this study, dwellings with earthen architecture were investigated with different independent measurement techniques in order to determine appropriate methods for reliable dose assessment of the dwellers. While for radon dose assessment, radon gas measurement and the assumption of a common indoor equilibrium factor often are sufficient, thoron gas has proven to be an unreliable surrogate for a direct measurement of thoron decay products. Active/time-resolved but also passive/integrating measurements of the total concentration of thoron decay products demonstrated being precise and efficient methods for determining the exposure and inhalation dose from thoron and its decay products. Exhalation rate measurements are a useful method for a rough dose estimate only if the exhalation rate is homogeneous throughout the house. Before the construction of a building in-vitro exhalation rate measurements on the building material can yield information about the exposure that is to be expected. Determining the unattached fraction of radon decay products and even more of thoron decay products leads to only a slightly better precision; this confirms the relative unimportance of the unattached thoron decay products due to their low concentration. The results of this study thereby give advice on the proper measurement method in similar exposure situations. Copyright © 2017 Elsevier B.V. All rights reserved.

Evidence of an Emerging Disturbance of Earthen Levees Causing Disastrous Floods in Italy

NASA Astrophysics Data System (ADS)

Orlandini, S.; Moretti, G.; Albertson, J. D.

2015-12-01

A levee failure occurred along the Secchia River, Northern Italy, on January 19, 2014, resulting in flood damage in excess of $500 Million (Figure). In response to this failure, immediate surveillance of other levees in the region led to the identification of a second breach developing on the neighboring Panaro River, where rapid mitigation efforts were successful in averting a full levee failure. The paired breach events that occurred along the Secchia and Panaro Rivers provided an excellent window on an emerging disturbance of levees and related failure mechanism. In the Secchia River, by combining the information content of photographs taken from helicopters in the early stage of breach development and 10-cm resolution aerial photographs taken in 2010 and 2012, animal burrows were found to exist in the precise levee location where the breach originated. In the Panaro River, internal erosion was observed to occur at a location where a crested porcupine den was known to exist and this erosion led to the collapse of the levee top. Evidence collected suggested that it is quite likely that the levee failure of the Secchia River was of a similar mechanism as the observed failure of the Panaro River. Detailed numerical modeling of rainfall, river flow, and variably saturated flow occurring in disturbed levees in response to complex hydroclimatic forcing indicated that the levee failure of the Secchia River may have been triggered by direct river inflow into the den system or collapse of a hypothetical den separated by a 1-m earthen wall from the levee riverside, which saturated during the hydroclimatic event. It is important to bring these processes to the attention of hydrologists and geotechnical engineers as well as to trigger an interdisciplinary discussion on habitat fragmentation and wildlife shifts due to development and climate pressures. These disturbances come together with changes in extreme events to inform the broader concern of risk analysis due to floods.

Methods for predicting peak discharge of floods caused by failure of natural and constructed earthen dams

USGS Publications Warehouse

Walder, Joseph S.; O'Connor, Jim E.

1997-01-01

Floods from failures of natural and constructed dams constitute a widespread hazard to people and property. Expeditious means of assessing flood hazards are necessary, particularly in the case of natural dams, which may form suddenly and unexpectedly. We revise statistical relations (derived from data for past constructed and natural dam failures) between peak discharge (Qp) and water volume released (V0) or drop in lake level (d) but assert that such relations, even when cast into a dimensionless form, are of limited utility because they fail to portray the effect of breach-formation rate. We then analyze a simple, physically based model of dam-breach formation to show that the hydrograph at the breach depends primarily on a dimensionless parameter η=kV0/gl/2d7/2, where k is the mean erosion rate of the breach and g is acceleration due to gravity. The functional relationship between Qp and η takes asymptotically distinct forms depending on whether η ≪ 1 (relatively slow breach formation or small lake volume) or η ≫ 1 (relatively fast breach formation or large lake volume). Theoretical predictions agree well with data from dam failures for which k, and thus η, can be estimated. The theory thus provides a rapid means of predicting the plausible range of values of peak discharge at the breach in an earthen dam as long as the impounded water volume and the water depth at the dam face can be estimated.

Ecological effects of co-culturing sea cucumber Apostichopus japonicus (Selenka) with scallop Chlamys farreri in earthen ponds

NASA Astrophysics Data System (ADS)

Ren, Yichao; Dong, Shuanglin; Qin, Chuanxin; Wang, Fang; Tian, Xiangli; Gao, Qinfeng

2012-01-01

Monthly changes in sedimentation and sediment properties were studied for three different culture treatments: sea cucumber monoculture (Mc), sea cucumber and scallop polyculture (Ps-c) and scallop monoculture (Ms). Results indicated that the survival rate of sea cucumber was significantly higher in Ps-c cultures than in Mc cultures. Sea cucumber yield was 69.6% higher in Ps-c culture than in Mc culture. No significant differences in body weight and scallop shell length were found between Ps-c and Ms cultures. The mean sedimentation rate of total particulate matter (TPM) was 72.2 g/(m2·d) in Ps-c cultures, with a maximum of 119.7 g/(m2·d), which was markedly higher than that of Mc (mean value). Sedimentation rates of organic matter (OM), total organic carbon (TOC), total nitrogen (TN) and total phosphorus (TP) in Ps-c cultures were also significantly higher than those in Mc cultures. TOC and TN contents of sediment increased rapidly in the first 5 months in Ms cultures and remained at a high level. TOC and TN contents in Mc and Ps-c cultures decreased during sea cucumber feeding seasons and increased during sea cucumber dormancy periods (summer and winter). The study demonstrates that co-culture of sea cucumber and scallop in earthen ponds is an alternative way to alleviate nutrient loads and improve water quality in coastal aquaculture systems. Moreover, it provides the additional benefit of an increased sea cucumber yield.

Soil microbiology and soil health assessment

USDA-ARS?s Scientific Manuscript database

Soil scientists have long recognized the importance of soil biology in ecological health. In particular, soil microbes are crucial for many soil functions including decomposition, nutrient cycling, synthesis of plant growth regulators, and degradation of synthetic chemicals. Currently, soil biologis...

Investigating the Effect of Compaction Characteristics on the Erodibility of Cohesive Soils Using the JET Method

NASA Astrophysics Data System (ADS)

Asghari Tabrizi, A.; LaRocque, L. A.; Chaudhry, M.; Imran, J.

2013-12-01

Several flood disasters occur every year all over the world, mostly due to levee and dam failure which result in human fatalities as well as devastating economic damages. To model and predict earthen embankment failures for the preparation of emergency action plans and risk assessments, the soil erodibility by flowing water is an essential parameter. The determination of erodibility becomes even more complicated for cohesive soils because of the large number of parameters controlling their erosion behavior (e.g. clay content, plasticity, compaction effort, compaction water content) and the difficulty of estimating these parameters. In this study the effect of the compaction energy and compaction water content on the erodibility of a sandy loam soil was assessed. Soil samples were prepared in a standard diameter compaction mold, 101.6 mm, for three levels of compaction effort and water content (i.e. low, medium, and high) with two replications for each case (18 tests total) and examined using the jet erosion test (JET). Observations from qualitative and statistical analyses of the data are: 1) a wide range of erodibility, from very erodible to very resistant, was produced by changes in the compaction characteristics; 2) for a given compaction energy, the erosion resistance based on the detachment rate coefficient kd tends to become minimum near the optimum compaction water content. On the dry side of optimum compaction water content, kd decreases with steep gradients by increasing the water content, while it increases with a flatter gradient on the wet side; 3) At a given water content, the soil erosion resistance increases with compaction efforts; 4) compaction water content influences soil erosibility more than compaction energy, especially on the dry side of the optimum compaction water content; and 5) for a given compaction effort, the critical shear stress increases with water content up to an optimum water content and then it decreases which is in consistent

Design and Installation of a Disposal Cell Cover Field Test

DOE Office of Scientific and Technical Information (OSTI.GOV)

Benson, C.H.; Waugh, W.J.; Albright, W.H.

2011-02-27

The U.S. Department of Energy’s Office of Legacy Management (LM) initiated a cover assessment project in September 2007 to evaluate an inexpensive approach to enhancing the hydrological performance of final covers for disposal cells. The objective is to accelerate and enhance natural processes that are transforming existing conventional covers, which rely on low-conductivity earthen barriers, into water balance covers, that store water in soil and release it as soil evaporation and plant transpiration. A low conductivity cover could be modified by deliberately blending the upper layers of the cover profile and planting native shrubs. A test facility was constructed atmore » the Grand Junction, Colorado, Disposal Site to evaluate the proposed methodology. The test cover was constructed in two identical sections, each including a large drainage lysimeter. The test cover was constructed with the same design and using the same materials as the existing disposal cell in order to allow for a direct comparison of performance. One test section will be renovated using the proposed method; the other is a control. LM is using the lysimeters to evaluate the effectiveness of the renovation treatment by monitoring hydrologic conditions within the cover profile as well as all water entering and leaving the system. This paper describes the historical experience of final covers employing earthen barrier layers, the design and operation of the lysimeter test facility, testing conducted to characterize the as-built engineering and edaphic properties of the lysimeter soils, the calibration of instruments installed at the test facility, and monitoring data collected since the lysimeters were constructed.« less

Self-compensating tensiometer and method

DOEpatents

Hubbell, Joel M.; Sisson, James B.

2003-01-01

A pressure self-compensating tensiometer and method to in situ determine below grade soil moisture potential of earthen soil independent of changes in the volume of water contained within the tensiometer chamber, comprising a body having first and second ends, a porous material defining the first body end, a liquid within the body, a transducer housing submerged in the liquid such that a transducer sensor within the housing is kept below the working fluid level in the tensiometer and in fluid contact with the liquid and the ambient atmosphere.

Effects of long-term soil and crop management on soil hydraulic properties for claypan soils

USDA-ARS?s Scientific Manuscript database

Regional and national soil maps have been developed along with associated soil property databases to assist users in making land management decisions based on soil characteristics. These soil properties include average values from soil characterization for each soil series. In reality, these propert...

Lunar soil properties and soil mechanics

NASA Technical Reports Server (NTRS)

Mitchell, J. K.; Houston, W. N.; Hovland, H. J.

1972-01-01

The study to identify and define recognizable fabrics in lunar soil in order to determine the history of the lunar regolith in different locations is reported. The fabric of simulated lunar soil, and lunar soil samples are discussed along with the behavior of simulated lunar soil under dynamic and static loading. The planned research is also included.

The early warning system of landslides and sediment runoffs using meteorological condition including rainfall-soil moisture index (Invited)

NASA Astrophysics Data System (ADS)

Kubota, T.; Silva, I. C.; Hasnawir, H.

2009-12-01

The research including observation of rain, soil moisture content and sediment discharge is conducted on a torrent in northern Kyushu whose geology consists of Paleozoic metamorphic rocks (mainly schist) and whose vegetation consists of mainly Japanese cypress and cedar. Soil depth is approximately 50cm in average and permeability k is 0.1~0.01 order. With data obtained by the observation for more than 4 years, standard rainfalls of warning and evacuation against the sudden sediment runoffs are analyzed. Then, the result was compared with the ones in Nuevo Leon Mexico (geology of schist, slate, k=0.01~0.001 order) and in southern Sulawesi Island Indonesia (volcanic geology, k=0.001~0.0001 order). Hitherto, various methods were proposed to analyze the warning critical standard for landslide disaster or large sediment discharge. In this study, we employed Hirano's element slope runoff theory, the Self Organized Criticality Assumption (SOC), and the Elementary Catastrophe Theory (ETC) to analyze the data, although the soil moisture fluctuation, meteorological condition such as upper air wind and dew point depression, the rainfall-soil moisture index provided by Japan Meteorological Agency was considered. The last one is a cutting edge technology based on the tank model calculation of soil moisture content combined with short term rainfall prediction which is a product of numerical simulation using radar image advection analysis compensated with surface rain data and with orographic rain effect. In Hirano's theory, we can describe the critical rain Rc and rain intensity Ric as following equation. Q/A/M/ cosθ = Ri ∫(r*cosθ)dt = Ri*R (1) ∴ Ric*Rc = C (2) Here, Q: sediment runoff or debris flow discharge, A: watershed area, M: function concerning with sediment deposit features on the upstream torrents or slopes (porosity, torrent bed slope gradient, sediment accumulation length and depth, cohesion), t: time, θ: torrent bed or hillside slope gradient, r: instant

Use of coal fly ash and other waste products in soil stabilization and road construction including non-destructive testing of roadways.

DOT National Transportation Integrated Search

2012-06-01

An extensive laboratory testing program was performed on subgrade soils stabilized using fly ash and : lime kiln dust. The laboratory program included measurements of: compaction curves, small strain elastic moduli, : resilient modulus (Mr), Briaud C...

Use of coal fly ash and other waste products in soil stabilization and road construction-including non-destructive testing of roadways.

DOT National Transportation Integrated Search

2012-02-01

An extensive laboratory testing program was performed on subgrade soils stabilized using fly ash and lime kiln dust. The laboratory : program included measurements of: compaction curves, small strain elastic moduli, resilient modulus (Mr), Briaud Com...

Soil

USDA-ARS?s Scientific Manuscript database

Soil is a diverse natural material characterized by solid, liquid, and gas phases that impart unique chemical, physical, and biological properties. Soil provides many key functions, including supporting plant growth and providing environmental remediation. Monitoring key soil properties and processe...

Repair, Evaluation, Maintenance, and Rehabilitation Research Program: The Effects of Vegetation on these Structural Integrity of Sandy Levees.

DTIC Science & Technology

1991-08-01

cracking in earth dams commonly occurs by hydraulic fracturing . Hydraulic fracturing is a tensile separation along an internal surface in a 25 soil mass...stress. This hydraulic fracturing is facilitated by differential settle- ment and internal stress transfer in an earthen structure. Sherard also showed...the hydraulic fracturing . 42. BioLic activity, i.e., the actions of plant roots and burrowing animals, has provided a popular explanation for pipe

Working with soils: soil science continuing professional development

NASA Astrophysics Data System (ADS)

Hannam, Jacqueline; Thompson, Dick

2017-04-01

The British Society of Soil Science launched the Working with Soils professional competency programme in 2011. This was in response to concerns from practitioners and professionals of a significant skills gap in various sectors that require soil science skills. The programme includes one and two day courses that cover the qualifications, knowledge and skills required of a professional scientist or engineer conducting a range of contract work. All courses qualify for continuing professional development points with various professional practice schemes. Three courses cover the foundations of soil science namely; describing a soil profile, soil classification and understanding soil variability in the field and landscape. Other tailored courses relate to specific skills required from consultants particularly in the planning process where land is assessed for agricultural quality (agricultural land classification). New courses this year include soil handling and restoration that provides practitioners with knowledge of the appropriate management of large volumes of soil that are disturbed during development projects. The courses have so far successfully trained over 100 delegates ranging from PhD students, environmental consultants and government policy advisors.

Construction and performance of a long-term earthen liner experiment

USGS Publications Warehouse

Cartwright, Keros; Krapac, Ivan G.; Bonaparte, Rudolph

1990-01-01

In land burial schemes, compacted soil barriers with low hydraulic conductivity are commonly used in cover and liner systems to control the movement of liquids and prevent groundwater contamination. An experimental liner measuring 8 x 15 x 0.9 m was constructed with design criteria and equipment to simulate construction of soil liners built at waste disposal facilities. The surface of the liner was flooded with a 29.5 cm deep pond on April 12, 1988. Infiltration of water into the liner has been monitored for two years using 4 large-ring (1.5 m OD) and 32 small-ring (0.28 m OD) infiltrometers, and a water-balance that accounts for total infiltration and evaporation. Average long-term infiltration fluxes based on two years of monitoring are 5.8 x 10-9 cm/s, 6.0 x 10-8 cm/s and 5.6 x 10-8 for the large-ring, small-ring, and water-balance data, respectively. The saturated hydraulic conductivity of the liner based on small-ring data, estimated using Darcy's Law and the Green-Ampt Approximation, is 3 x 10-8 and 4 x 10-8 cm/s, respectively. All sets of data indicate that the liner's performance exceed that which is required by the U.S. EPA.

Environmental isotope investigation for the identification of source of springs observed in the hillock on the left flank of Gollaleru Earthen Dam, Andhra Pradesh, India

NASA Astrophysics Data System (ADS)

Noble, J.; Arzoo Ansari, MD

2017-07-01

A hydrometric, hydrochemical and environmental isotopic study was conducted to identify the source and origin of observed springs on the foot of the hillock abutting the left flank of the Gollaleru earthen dam, Nandyal, Andhra Pradesh, India. Water samples (springs, reservoir water and groundwater) in and around the dam area were collected and analyzed for environmental isotopes (δ^{18}!O, δ2H and 3H) and hydrochemistry. Reservoir level, spring discharges and physico-chemical parameters (temperature, electrical conductivity, pH, etc.) were monitored in-situ. Isotopic results indicated that the source of springs is from the Owk reservoir and groundwater contribution to the springs is insignificant. Based on hydrometric observations, it is inferred that the springs might be originated from the reservoir level of 209 m amsl. It is found that the lower spring discharges were derived from diffuse sources (seepage) which could be a mixture of reservoir water and the groundwater, while the relatively higher spring discharges were resulted from concentrated sources (leakage) from the reservoir. Thus, the study portraits the usefulness of isotope techniques in understanding the dam seepage/leakage related problems.

Advancing internal erosion monitoring using seismic methods in field and laboratory studies

NASA Astrophysics Data System (ADS)

Parekh, Minal L.

This dissertation presents research involving laboratory and field investigation of passive and active methods for monitoring and assessing earthen embankment infrastructure such as dams and levees. Internal erosion occurs as soil particles in an earthen structure migrate to an exit point under seepage forces. This process is a primary failure mode for dams and levees. Current dam and levee monitoring practices are not able to identify early stages of internal erosion, and often the result is loss of structure utility and costly repairs. This research contributes to innovations for detection and monitoring by studying internal erosion and monitoring through field experiments, laboratory experiments, and social and political framing. The field research in this dissertation included two studies (2009 and 2012) of a full-scale earthen embankment at the IJkdijk in the Netherlands. In both of these tests, internal erosion occurred as evidenced by seepage followed by sand traces and boils, and in 2009, eventual failure. With the benefit of arrays of closely spaced piezometers, pore pressure trends indicated internal erosion near the initiation time. Temporally and spatially dense pore water pressure measurements detected two pore water pressure transitions characteristic to the development of internal erosion, even in piezometers located away from the backward erosion activity. At the first transition, the backward erosion caused anomalous pressure decrease in piezometers, even under constant or increasing upstream water level. At the second transition, measurements stabilized as backward erosion extended further upstream of the piezometers, as shown in the 2009 test. The transitions provide an indication of the temporal development and the spatial extent of backward erosion. The 2012 IJkdijk test also included passive acoustic emissions (AE) monitoring. This study analyzed AE activity over the course of the 7-day test using a grid of geophones installed on the

Soil Ciliates from Saudi Arabia, Including Descriptions of Two New Genera and Six New Species.

PubMed

Foissner, Wilhelm; Quintela-Alonso, Pablo; Al-Rasheid, Khaled

2008-01-01

Six soil samples from natural and cultivated sites of Saudi Arabia were investigated for ciliate diversity, using the non-flooded Petri dish culture method, live observation, and silver impregnation. We identified 135 species, all new for the fauna of Saudi Arabia, of which seven were undescribed: Spathidium alqasabi nov. spec.; Enchelyodon alqasabi nov. spec.; Metauroleptus arabicus nov. gen., nov. spec.; Pseudohemisincirra arabica nov. gen., nov. spec.; Saudithrix terricola​ Berger, Al-Rasheid and Foissner, 2006; Oxytricha arabica nov. spec.; and Erimophrya monostyla nov. spec. Based on Spathidium alqasabi, S. seppelti foissneri​ Vd'ačný et al., 2006 and S. seppelti etoschense​ Foissner et al., 2002 are raised to species rank; for the latter, a new name is required to avoid homonymy: Spathidium fraterculum nov. nom. The new genus Metauroleptus, which possesses two long and two to three short ventral cirral rows, generates all dorsal kineties intrakinetally and produces caudal cirri exclusively in dorsal kinety 1. Metauroleptus belongs to the hypotrichs, while family classification remains doubtful. The same applies to the new hypotrich genus Pseudohemisincirra, which has frontoventral and transverse cirri, while buccal cirri and caudal cirri are absent. The number of species contained in Saudi Arabian soils, including sand dunes, is in the range reported from other regions of the earth, suggesting that ciliates are well adapted to dry habitats, possibly mainly by their ability to produce very resistant resting cysts, most surviving for a long time due to reduced metazoan predation.

Toxicity of pesticides associated with potato production, including soil fumigants, to snapping turtle eggs (Chelydra serpentina).

PubMed

de Solla, Shane Raymond; Palonen, Kimberley Elizabeth; Martin, Pamela Anne

2014-01-01

Turtles frequently oviposit in soils associated with agriculture and, thus, may be exposed to pesticides or fertilizers. The toxicity of a pesticide regime that is used for potato production in Ontario on the survivorship of snapping turtle (Chelydra serpentina) eggs was evaluated. The following treatments were applied to clean soil: 1) a mixture of the pesticides chlorothalonil, S-metolachlor, metribuzin, and chlorpyrifos, and 2) the soil fumigant metam sodium. Turtle eggs were incubated in soil in outdoor plots in which these mixtures were applied at typical and higher field application rates, where the eggs were subject to ambient temperature and weather conditions. The pesticide mixture consisting of chlorothalonil, S-metolachlor, metribuzin, and chlorpyrifos did not affect survivorship, deformities, or body size at applications up to 10 times the typical field application rates. Hatching success ranged between 87% and 100% for these treatments. Metam sodium was applied at 0.1¯ times, 0.3¯ times, 1 times, and 3 times field application rates. Eggs exposed to any application of metam sodium had 100% mortality. At typical field application rates, the chemical regime associated with potato production does not appear to have any detrimental impacts on turtle egg development, except for the use of the soil fumigant metam sodium, which is highly toxic to turtle eggs at the lowest recommended application rate. © 2013 SETAC.

The utilisation of municipal waste compost for the reclamation of anthropogenic soils: implications on C dynamics.

NASA Astrophysics Data System (ADS)

Said-Pullicino, D.; Bol, R.; Gigliotti, G.

2009-04-01

The application of municipal waste compost (MWC) and other organic materials may serve to enhance soil fertility and increase C stocks of earthen materials and mine spoils used in land reclamation activities, particularly in the recovery of degraded areas left by exhausted quarries, mines, abandoned industrial zones, degraded natural areas and exhausted landfill sites. Such land management options may serve as a precondition for landscaping and reclamation of degraded areas, reforestation or agriculture. In fact, previous results have shown that compost application to the capping layer of a landfill covering soil significantly enhanced the fertility, evidenced by an improvement in soil structure, porosity and water holding capacity, an increase in the relative proportion of recalcitrant C pools and an increase in soil nutrient content, microbial activity and soil microbial biomass. Proper management of MWC requires a capacity to understand and predict their impacts on C dynamics in the field subsequent to application. Although numerous works deal with the effects of compost application in agricultural systems, little is known on how land rehabilitation practices effect C dynamics in such relatively young soil systems. The estimation of SOC pools and their potential turnover rates in land reclamation activities is fundamental to our understanding of terrestrial C dynamics. In the framework of a long-term field experiment, the objective of this work was to evaluate the temporal and spatial dynamics of compost-derived organic matter with respect to the major processes involved in organic matter cycling in an anthropogenic landfill covering soil originally amended with a single dose of MWC. We investigated long-term organic C dynamics in such systems by collecting samples at different depths over a 10 year chronosequence subsequent to compost application to the top layer of the landfill covering soil. Variations in the stable isotope composition (delta 13C) of the soil

Soil Organic Matter and Soil Productivity: Searching for the Missing Link

Treesearch

Felipe G. Sanchez

1998-01-01

Soil-organic matter (SOM) is a complex array of components including soil fauna and flora at different stages of decomposition (Berg et al., 1982). Its concentration in soils can vary from 0.5% in mineral soils to almost 100% in peat soils (Brady, 1974). Organic matter (OM) in the surface mineral soil is considered a major determinant of forest ecosystem productivity...

Soils in Schools: Embedding Soil Science in STEM

ERIC Educational Resources Information Center

Bryce, Alisa

2015-01-01

Soil science, though relevant to a variety of subjects including science, geography, mathematics, social sciences and history, is typically perceived as a subgenre of agriculture. With a global need for soil scientists, and declining numbers in university soil courses, there's a growing gap between science needs and providers. One way to promote…

Soil organic carbon dynamics jointly controlled by climate, carbon inputs, soil properties and soil carbon fractions.

PubMed

Luo, Zhongkui; Feng, Wenting; Luo, Yiqi; Baldock, Jeff; Wang, Enli

2017-10-01

Soil organic carbon (SOC) dynamics are regulated by the complex interplay of climatic, edaphic and biotic conditions. However, the interrelation of SOC and these drivers and their potential connection networks are rarely assessed quantitatively. Using observations of SOC dynamics with detailed soil properties from 90 field trials at 28 sites under different agroecosystems across the Australian cropping regions, we investigated the direct and indirect effects of climate, soil properties, carbon (C) inputs and soil C pools (a total of 17 variables) on SOC change rate (r C , Mg C ha -1  yr -1 ). Among these variables, we found that the most influential variables on r C were the average C input amount and annual precipitation, and the total SOC stock at the beginning of the trials. Overall, C inputs (including C input amount and pasture frequency in the crop rotation system) accounted for 27% of the relative influence on r C , followed by climate 25% (including precipitation and temperature), soil C pools 24% (including pool size and composition) and soil properties (such as cation exchange capacity, clay content, bulk density) 24%. Path analysis identified a network of intercorrelations of climate, soil properties, C inputs and soil C pools in determining r C . The direct correlation of r C with climate was significantly weakened if removing the effects of soil properties and C pools, and vice versa. These results reveal the relative importance of climate, soil properties, C inputs and C pools and their complex interconnections in regulating SOC dynamics. Ignorance of the impact of changes in soil properties, C pool composition and C input (quantity and quality) on SOC dynamics is likely one of the main sources of uncertainty in SOC predictions from the process-based SOC models. © 2017 John Wiley & Sons Ltd.

National Program for Inspection of Non-Federal Dams. Baker Floodwater Reservoir Site 11 (NH 00478), NHWRB No. 249.13, Merrimack River Basin, Wentworth, New Hampshire. Phase I Inspection Report.

DTIC Science & Technology

1979-07-01

General 5-1 b. Design Data 5-1 c. Experience Data 5-1 d. Visual Observation 5-1 e. Overtopping Potential 5-1 f. Dam Failure Analysis 5-2 6. STRUCTURAL...the Soil Conservation Service, Durham, New Hampshire. The construction * contractor was Robie Construction Company , Inc. i. Normal Operating...INVENTORY OF DAMS P 0O - ... - SECTION 5 HYDROLOGY AND HYDRAULIC ANALYSIS • 5.1 Evaluation of Features a. General. Baker Dam Site 11 is an earthen

Soil 4 Youth: Charting New Territory in Canadian High School Soil Science Education

ERIC Educational Resources Information Center

Krzic, Maja; Wilson, Julie; Basiliko, Nathan; Bedard-Haughn, Angela; Humphreys, Elyn; Dyanatkar, Saeed; Hazlett, Paul; Strivelli, Rachel; Crowley, Chris; Dampier, Lesley

2014-01-01

As global issues continue to place increasing demands on soil resources, the need to provide soil science education to the next generation of soil scientists and the general public is becoming more imminent. In many countries around the world, including Canada, soil is either not included in the high school curriculum or it is not covered in…

Growth and production performance of monosex tilapia (Oreochromis niloticus) fed with homemade feed in earthen mini ponds.

PubMed

Ahmed, G U; Sultana, N; Shamsuddin, M; Hossain, M Belal

2013-12-01

Field experiment was conducted to evaluate the growth performance of monosex tilapia using homemade feed with Peninsula Group fish meal and commercially available feed with local fish meal in earthen mini ponds from June-September 2010. Three ponds (T1) were supplied with prepared feed and the other three ponds (T2) with commercially available fish feed. Fish were fed at the rate of 10% of their body weight for the first thirty days then gradually reduced to 6% for the next ten days, 2% for the next ten days and 3% for remaining days. The temperature were ranged from 31.5-33.0 degrees C, DO from 5.5-15 mg L(-1) in T1 and 6.5-14 mg L(-1) in T2, pH from 7.1-8.0 in T1 and 7.1-7.7 in T2, alkalinity from 105-160 mg L(-1) inT1 and 100-145 mg L(-1) in T2, nitrate was 0.06 mg L(-1) in both treatments and ammonia from 0.02 and 0.04 mg L(-1) in T1 and T2, respectively. The results of the present study showed that the best weight gain was observed as 123.48 g in T1 than T2 (111.82 g). The Specific Growth Rate (SGR) was recorded 3.09 and 2.97 and the Food Conversion Ratio (FCR) was 1.51 and 1.40 in T1 and T2, respectively. There was significant (p < 0.05) variation among the survival rate (%) of fishes which were 75.55 and 90.37% in T1 and T2, respectively. The fish productions were 19076 and 16312.11 kg ha(-1) in T1 and T2. The highest net profit (Taka/ha/70 days) of Tk. 15, 83,213 was obtained with T1 So, the prepared feed showed better performance with monosex tilapia in compared with commercial fish feed with local fish meal.

Shaping an Optimal Soil by Root-Soil Interaction.

PubMed

Jin, Kemo; White, Philip J; Whalley, William R; Shen, Jianbo; Shi, Lei

2017-10-01

Crop production depends on the availability of water and mineral nutrients, and increased yields might be facilitated by a greater focus on roots-soil interactions. Soil properties affecting plant growth include drought, compaction, nutrient deficiency, mineral toxicity, salinity, and submergence. Plant roots respond to the soil environment both spatially and temporally by avoiding stressful soil environments and proliferating in more favorable environments. We observe that crops can be bred for specific root architectural and biochemical traits that facilitate soil exploration and resource acquisition, enabling greater crop yields. These root traits affect soil physical and chemical properties and might be utilized to improve the soil for subsequent crops. We argue that optimizing root-soil interactions is a prerequisite for future food security. Copyright © 2017 Elsevier Ltd. All rights reserved.

ISTA 14--impact of antibiotics from pig slurry on soil microbial communities, including the basidiomycete Trametes versicolor.

PubMed

Igel-Egalon, Angélique; Cheviron, Nathalie; Hedde, Mickael; Hernandez-Raquet, Guillermina; Mougin, Christian

2012-03-01

Livestock slurry containing antibiotics is a source of contamination of agricultural soils, with possible effects on soil function and micro-organisms. Extracellular oxido-reductases and hydrolases from the fungus T. versicolor and fungal growth were monitored in liquid cultures in the presence of tetracycline, lincomycine, sulfadiazine and ciprofloxacin for 10 days, in order to assess the suitability of these enzymes as biomarkers. Among the conditions of treatment, statistical analysis demonstrated an increase in manganese-dependent peroxidase after exposure to sulfadiazine at 1 mg/L when compared with the control. Acid phosphatase activity was decreased by lincomycine at 1 or 10 mg/L. Conversely, β-glucosidase activity increased in the presence of this antibiotic at 10 mg/L. In Terrestrial Model Ecosystems spiked with contaminated pig slurry, lincomycine at the concentration of 8 or 80 μg/kg dry soil, and ciprofloxacin at 250 ng/kg dry soil decreased the activity of soil dehydrogenase, when compared with a green slurry treatment, over 28-day incubations. Laccase activity was similarly decreased in the presence of the highest concentration of antibiotics. We determined bacterial and fungal biomasses using Q-PCR. Bacterial biomass was increased in the presence of lincomycine at 80 μg/kg whatever the time of exposure, and to a lesser extent in the presence of ciprofloxacin at 250 ng/kg, but only at day 28. In contrast, both antibiotics, whatever their concentrations, did not modify fungal biomass in soil. In conclusion, we were unable to demonstrate important effects of antibiotics at concentrations found in the agricultural environment. Copyright © 2011 Wiley Periodicals, Inc.

Ecological effects of co-culturing the sea cucumber Apostichopus japonicus with the Chinese white shrimp Fenneropenaeus chinensis in an earthen pond

NASA Astrophysics Data System (ADS)

Zhou, Shun; Ren, Yichao; Pearce, Christopher M.; Dong, Shuanglin; Tian, Xiangli; Gao, Qinfeng; Wang, Fang

2017-01-01

Using net enclosures in an earthen pond, we established three culture treatments with the sea cucumber Apostichopus japonicus and the Chinese white shrimp Fenneropenaeus chinensis: monoculture of sea cucumbers (C), monoculture of shrimp (S), and co-culture of the two species (CS). We measured levels of suspended particulate matter in the water column; total organic matter, total organic carbon, total nitrogen, and carbon/nitrogen ratios in both settling particles and the sediment; and chlorophyll a levels in the sediment. We then compared these variables between the three treatments. We also examined growth, survival, and yield of the two species in the different treatments. From June to September, the mean monthly suspended particulate matter sedimentation rates in the CS and S treatments were significantly ( P<0.05) greater than those in the C treatment. From August to November, the mean monthly total organic matter, total organic carbon, total nitrogen, and chlorophyll a contents in the sediment in the CS and S treatments were significantly ( P <0.05) greater than those in the C treatment. Final wet weight, specific growth rate, survival rate, and total yield of sea cucumbers in co-culture were all significantly greater than those of sea cucumbers in monoculture. There were no significant differences among any of these variables for shrimp reared in the two systems. The bioturbation of the sediment and fecal production of the shrimp likely supplied natural food for the sea cucumbers. Co-culture of the two species is a viable option for increasing yield per unit area, maximizing use of the water body, and diversifying crop production.

Soil Carbon Cycling - More than Changes in Soil Organic Carbon Stocks

NASA Astrophysics Data System (ADS)

Lorenz, K.

2015-12-01

Discussions about soil carbon (C) sequestration generally focus on changes in soil organic carbon (SOC) stocks. Global SOC mass in the top 1 m was estimated at about 1325 Pg C, and at about 3000 Pg C when deeper soil layers were included. However, both inorganically and organically bound carbon forms are found in soil but estimates on global soil inorganic carbon (SIC) mass are even more uncertain than those for SOC. Globally, about 947 Pg SIC may be stored in the top 1 m, and especially in arid and semi-arid regions SIC stocks can be many times great than SOC stocks. Both SIC and SOC stocks are vulnerable to management practices, and stocks may be enhanced, for example, by optimizing net primary production (NPP) by fertilization and irrigation (especially optimizing belowground NPP for enhancing SOC stocks), adding organic matter (including black C for enhancing SOC stocks), and reducing soil disturbance. Thus, studies on soil C stocks, fluxes, and vulnerability must look at both SIC and SOC stocks in soil profiles to address large scale soil C cycling.

Ecosystem functions including soil organic carbon, total nitrogen and available potassium are crucial for vegetation recovery.

PubMed

Qiu, Kaiyang; Xie, Yingzhong; Xu, Dongmei; Pott, Richard

2018-05-15

The effects of biodiversity on ecosystem functions have been extensively studied, but little is known about the effects of ecosystem functions on biodiversity. This knowledge is important for understanding biodiversity-ecosystem functioning relationships. Desertification reversal is a significant global challenge, but the factors that play key roles in this process remain unclear. Here, using data sampled from areas undergoing desertification reversal, we identify the dominant soil factors that play a role in vegetation recovery with ordinary least squares and structural equation modelling. We found that ecosystem functions related to the cycling of soil carbon (organic C, SOC), nitrogen (total N, TN), and potassium (available K, AK) had the most substantial effects on vegetation recovery. The effects of these ecosystem functions were simultaneously influenced by the soil clay, silt and coarse sand fractions and the soil water content. Our findings suggest that K plays a critical role in ecosystem functioning and is a limiting factor in desertification reversal. Our results provide a scientific basis for desertification reversal. Specifically, we found that plant biodiversity may be regulated by N, phosphorus (P) and K cycling. Collectively, biodiversity may respond to ecosystem functions, the conservation and enhancement of which can promote the recovery of vegetation.

Evaluating soil contamination

USGS Publications Warehouse

Beyer, W.N.

1990-01-01

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.

Keys to soil taxonomy by soil survey staff (sixth edition)

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

1994-12-31

This publication, Keys to Soil Taxonomy, serves two purposes. It provides the taxonomic keys necessary for the classification of soils according to Soil Taxonomy in a form that can be used easily in the field, and it also acquaints users of Soil Taxonomy with recent changes in the classification system. This volume includes all revisions of the keys that have so far been approved, replacing the original keys in Soil Taxonomy: A Basic System of Soil Classification for Making and Interpreting Soil Surveys (1975), the work on which this abridged version, first published in 1983, is based. This publication incorporatesmore » all amendments approved to date and published in National Soil Taxonomy Handbook (NSTH) Issues 1-17.« less

Transformation of soil microbial community structure in response to anaerobic soil disinfestation for soil-borne disease control in strawberry

USDA-ARS?s Scientific Manuscript database

Anaerobic soil disinfestation (ASD) has been used to control soil-borne pathogens and nematodes in various plant production systems including strawberries. Disease control is commonly attributed to the depletion of oxygen and the generation of toxic compounds, including organic acids and volatiles....

Using soil health to assess ecotoxicological impacts of pollutants on soil microflora.

PubMed

Bécaert, Valérie; Deschênes, Louise

2006-01-01

Microorganisms are essential for a properly functioning soil ecosystem. However, few methods allow an ecotoxicological evaluation of pollutant impact on the soil microbial community. This review proposes the use of the concept of soil health as an ecotoxicological evaluation tool for soil microflora. Initially limited to sustainable agriculture, the concept of soil health is now being applied to novel situations including contaminated and remediated soils. A large amount of work has been published in the last few decades on soil health indicators, and a review of the most relevant studies is presented here. The most cited work is that of the S-5518 committee set up in 1997 by the Soil Science Society of America (SSSA), which proposed to define soil quality as being "the capacity of a soil to function within the limits of an ecosystem, to support biological production, to maintain environmental quality and to support fauna and flora health." The soil health indicators reviewed here are the ones based on this definition because it relates well to sustainability and durability of the soil functions. Several indicators proposed in these studies could be employed in the evaluation of the ecotoxicological impact of pollutants on the soil microbial community, including microbial diversity, microbial activity, and functional stability. However, research is still required to unify the concept, to set threshold values, and to standardize methodologies.

Helping People Understand Soils - Perspectives from the US National Cooperative Soil Survey

NASA Astrophysics Data System (ADS)

Reich, Paul; Cheever, Tammy; Greene, Linda; Southard, Susan; Levin, Maxine; Lindbo, David L.; Monger, Curtis

2017-04-01

Throughout the history of the US National Cooperative Soil Survey (NCSS), soil science education has been a part of the mission to better understand one of our most precious natural resources: the Soil. The poster will highlight the many products and programs related to soils that USDA NRCS (soils.usda.gov) has developed over the years for K-12 and college/professional education. NRCS scientific publications covering topics on soil properties, soil classification, soil health and soil quality have become an important part of the university soil science curriculum. Classroom lesson plans and grade appropriate materials help K-12 teachers introduce soil concepts to students and include detailed instructions and materials for classroom demonstrations of soil properties. A Handbook for Collegiate Soils Contests support universities that conduct Collegiate Soil Judging contests.

Inversion of soil electrical conductivity data to estimate layered soil properties

USDA-ARS?s Scientific Manuscript database

CBulk apparent soil electrical conductivity (ECa) sensors respond to multiple soil properties, including clay content, water content, and salt content (i.e., salinity). They provide a single sensor value for an entire soil profile down to a sensor-dependent measurement depth, weighted by a nonlinear...

July: "Soils are living: Overview of soil biodiversity, global issues, and new resources"

USDA-ARS?s Scientific Manuscript database

The July poster will provide an overview of soil biology and the many ecosystem functions that soil organisms drive including their impact on global biodiversity, climate regulation, soil health/stability, and plant growth. Five main global issues related to soil biodiversity will be presented such ...

Combining phytoextraction and biochar addition improves soil biochemical properties in a soil contaminated with Cd.

PubMed

Lu, Huanping; Li, Zhian; Fu, Shenglei; Méndez, Ana; Gascó, Gabriel; Paz-Ferreiro, Jorge

2015-01-01

The main goal of phytoremediation is to improve ecosystem functioning. Soil biochemical properties are considered as effective indicators of soil quality and are sensitive to various environmental stresses, including heavy metal contamination. The biochemical response in a soil contaminated with cadmium was tested after several treatments aimed to reduce heavy metal availability including liming, biochar addition and phytoextraction using Amaranthus tricolor L. Two biochars were added to the soil: eucalyptus pyrolysed at 600 °C (EB) and poultry litter at 400 °C (PLB). Two liming treatments were chosen with the aim of bringing soil pH to the same values as in the treatments EB and PLB. The properties studied included soil microbial biomass C, soil respiration and the activities of invertase, β-glucosidase, β-glucosaminidase, urease and phosphomonoesterase. Both phytoremediation and biochar addition improved soil biochemical properties, although results were enzyme specific. For biochar addition these changes were partly, but not exclusively, mediated by alterations in soil pH. A careful choice of biochar must be undertaken to optimize the remediation process from the point of view of metal phytoextraction and soil biological activity. Copyright © 2014 Elsevier Ltd. All rights reserved.

Teaching Science with Soil.

ERIC Educational Resources Information Center

Schatz, Albert; Kriebs, Jean Oak

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…

Development and implementation of the software for visualization and analysis of data geophysical loggers

NASA Astrophysics Data System (ADS)

Gordeev, V. F.; Malyshkov, S. Yu.; Botygin, I. A.; Sherstnev, V. S.; Sherstneva, A. I.

2017-11-01

The general trend of modern ecological geophysics is changing priorities towards rapid assessment, management and prediction of ecological and engineering soil stability as well as developing brand new geophysical technologies. The article describes researches conducted by using multi-canal geophysical logger MGR-01 (developed by IMCES SB RAS), which allows to measure flux density of very low-frequency electromagnetic radiation. It is shown that natural pulsed electromagnetic fields of the earthen lithosphere can be a source of new information on Earth's crust and processes in it, including earthquakes. The device is intended for logging electromagnetic processes in Earth's crust, geophysical exploration, finding structural and lithological inhomogeneities, monitoring the geodynamic movement of Earth's crust, express assessment of seismic hazards. The data is gathered automatically from observation point network in Siberia

Mobility of arsenic and its compounds in soil and soil solution: the effect of soil pretreatment and extraction methods.

PubMed

Száková, J; Tlustos, P; Goessler, W; Frková, Z; Najmanová, J

2009-12-30

The effect of soil extraction procedures and/or sample pretreatment (drying, freezing of the soil sample) on the extractability of arsenic and its compounds was tested. In the first part, five extraction procedures were compared with following order of extractable arsenic portions: 2M HNO(3)>0.43 M CH(3)COOH>or=0.05 M EDTA>or=Mehlich III (0.2M CH(3)COOH+0.25 M NH(4)NO(3)+0.013 M HNO(3)+0.015 M NH(4)F+0.001 M EDTA) extraction>water). Additionally, two methods of soil solution sampling were compared, centrifugation of saturated soil and the use of suction cups. The results showed that different sample pretreatments including soil solution sampling could lead to different absolute values of mobile arsenic content in soils. However, the interpretation of the data can lead to similar conclusions as apparent from the comparison of the soil solution sampling methods (r=0.79). For determination of arsenic compounds mild extraction procedures (0.05 M (NH(4))(2)SO(4), 0.01 M CaCl(2), and water) and soil solution sampling using suction cups were compared. Regarding the real soil conditions the extraction of fresh samples and/or in situ collection of soil solution are preferred among the sample pretreatments and/or soil extraction procedures. However, chemical stabilization of the solutions should be allowed and included in the analytical procedures for determination of individual arsenic compounds.

Electricity generation in low cost microbial fuel cell made up of earthenware of different thickness.

PubMed

Behera, M; Ghangrekar, M M

2011-01-01

Performance of four microbial fuel cells (MFC-1, MFC-2, MFC-3 and MFC-4) made up of earthen pots with wall thicknesses of 3, 5, 7 and 8.5 mm, respectively, was evaluated. The MFCs were operated in fed batch mode with synthetic wastewater having sucrose as the carbon source. The power generation decreased with increase in the thickness of the earthen pot which was used to make the anode chamber. MFC-1 generated highest sustainable power density of 24.32 mW/m(2) and volumetric power of 1.04 W/m(3) (1.91 mA, 0.191 V) at 100 Ω external resistance. The maximum Coulombic efficiencies obtained in MFC-1, MFC-2, MFC-3 and MFC-4 were 7.7, 7.1, 6.8 and 6.1%, respectively. The oxygen mass transfer and oxygen diffusion coefficients measured for earthen plate of 3 mm thickness were 1.79 × 10(-5) and 5.38 × 10(-6) cm(2)/s, respectively, which implies that earthen plate is permeable to oxygen as other polymeric membranes. The internal resistance increased with increase in thickness of the earthen pot MFCs. The thickness of the earthen material affected the overall performance of MFCs.

Soil property effects on wind erosion of organic soils

NASA Astrophysics Data System (ADS)

Zobeck, Ted M.; Baddock, Matthew; Scott Van Pelt, R.; Tatarko, John; Acosta-Martinez, Veronica

2013-09-01

Histosols (also known as organic soils, mucks, or peats) are soils that are dominated by organic matter (OM > 20%) in half or more of the upper 80 cm. Forty two states have a total of 21 million ha of Histosols in the United States. These soils, when intensively cropped, are subject to wind erosion resulting in loss of crop productivity and degradation of soil, air, and water quality. Estimating wind erosion on Histosols has been determined by USDA-Natural Resources Conservation Service (NRCS) as a critical need for the Wind Erosion Prediction System (WEPS) model. WEPS has been developed to simulate wind erosion on agricultural land in the US, including soils with organic soil material surfaces. However, additional field measurements are needed to understand how soil properties vary among organic soils and to calibrate and validate estimates of wind erosion of organic soils using WEPS. Soil properties and sediment flux were measured in six soils with high organic contents located in Michigan and Florida, USA. Soil properties observed included organic matter content, particle density, dry mechanical stability, dry clod stability, wind erodible material, and geometric mean diameter of the surface aggregate distribution. A field portable wind tunnel was used to generate suspended sediment and dust from agricultural surfaces for soils ranging from 17% to 67% organic matter. The soils were tilled and rolled to provide a consolidated, friable surface. Dust emissions and saltation were measured using an isokinetic vertical slot sampler aspirated by a regulated suction source. Suspended dust was sampled using a Grimm optical particle size analyzer. Particle density of the saltation-sized material (>106 μm) was inversely related to OM content and varied from 2.41 g cm-3 for the soil with the lowest OM content to 1.61 g cm-3 for the soil with highest OM content. Wind erodible material and the geometric mean diameter of the surface soil were inversely related to dry clod

Soil protists: a fertile frontier in soil biology research.

PubMed

Geisen, Stefan; Mitchell, Edward A D; Adl, Sina; Bonkowski, Michael; Dunthorn, Micah; Ekelund, Flemming; Fernández, Leonardo D; Jousset, Alexandre; Krashevska, Valentyna; Singer, David; Spiegel, Frederick W; Walochnik, Julia; Lara, Enrique

2018-05-01

Protists include all eukaryotes except plants, fungi and animals. They are an essential, yet often forgotten, component of the soil microbiome. Method developments have now furthered our understanding of the real taxonomic and functional diversity of soil protists. They occupy key roles in microbial foodwebs as consumers of bacteria, fungi and other small eukaryotes. As parasites of plants, animals and even of larger protists, they regulate populations and shape communities. Pathogenic forms play a major role in public health issues as human parasites, or act as agricultural pests. Predatory soil protists release nutrients enhancing plant growth. Soil protists are of key importance for our understanding of eukaryotic evolution and microbial biogeography. Soil protists are also useful in applied research as bioindicators of soil quality, as models in ecotoxicology and as potential biofertilizers and biocontrol agents. In this review, we provide an overview of the enormous morphological, taxonomical and functional diversity of soil protists, and discuss current challenges and opportunities in soil protistology. Research in soil biology would clearly benefit from incorporating more protistology alongside the study of bacteria, fungi and animals.

Human land-use and soil change

USGS Publications Warehouse

Wills, Skye A.; Williams, Candiss O.; Duniway, Michael C.; Veenstra, Jessica; Seybold, Cathy; Pressley, DeAnn

2017-01-01

Soil change refers to the alteration of soil and soil properties over time in one location, as opposed to soil variability across space. Although soils change with pedogensis, this chapter focuses on human caused soil change. Soil change can occur with human use and management over long or short time periods and small or large scales. While change can be negative or positive; often soil change is observed when short-term or narrow goals overshadow the other soil’s ecosystem services. Many soils have been changed in their chemical, physical or biological properties through agricultural activities, including cultivation, tillage, weeding, terracing, subsoiling, deep plowing, manure and fertilizer addition, liming, draining, and irrigation. Assessing soil change depends upon the ecosystem services and soil functions being evaluated. The interaction of soil properties with the type and intensity of management and disturbance determines the changes that will be observed. Tillage of cropland disrupts aggregates and decreases soil organic carbon content which can lead to decreased infiltration, increased erosion, and reduced biological function. Improved agricultural management systems can increase soil functions including crop productivity and sustainability. Forest management is most intensive during harvesting and seedling establishment. Most active management in forests causes disturbance of the soil surface which may include loss of forest floor organic materials, increases in bulk density, and increased risk of erosion. In grazing lands, pasture management often includes periods of biological, chemical and physical disturbance in addition to the grazing management imposed on rangelands. Grazing animals have both direct and indirect impacts on soil change. Hoof action can lead to the disturbance of biological crusts and other surface features impairing the soil’s physical, biological and hydrological function. There are clear feedbacks between vegetative systems

Diel hysteresis between soil respiration and soil temperature in a biological soil crust covered desert ecosystem

PubMed Central

Li, Xinrong; Zhang, Peng; Chen, Yongle

2018-01-01

Soil respiration induced by biological soil crusts (BSCs) is an important process in the carbon (C) cycle in arid and semi-arid ecosystems, where vascular plants are restricted by the harsh environment, particularly the limited soil moisture. However, the interaction between temperature and soil respiration remains uncertain because of the number of factors that control soil respiration, including temperature and soil moisture, especially in BSC-dominated areas. In this study, the soil respiration in moss-dominated crusts and lichen-dominated crusts was continuously measured using an automated soil respiration system over a one-year period from November 2015 to October 2016 in the Shapotou region of the Tengger Desert, northern China. The results indicated that over daily cycles, the half-hourly soil respiration rates in both types of BSC-covered areas were commonly related to the soil temperature. The observed diel hysteresis between the half-hourly soil respiration rates and soil temperature in the BSC-covered areas was limited by nonlinearity loops with semielliptical shapes, and soil temperature often peaked later than the half-hourly soil respiration rates in the BSC-covered areas. The average lag times between the half-hourly soil respiration rates and soil temperature for both types of BSC-covered areas were two hours over the diel cycles, and they were negatively and linearly related to the volumetric soil water content. Our results highlight the diel hysteresis phenomenon that occurs between soil respiration rates and soil temperatures in BSC-covered areas and the negative response of this phenomenon to soil moisture, which may influence total C budget evaluations. Therefore, the interactive effects of soil temperature and moisture on soil respiration in BSC-covered areas should be considered in global carbon cycle models of desert ecosystems. PMID:29624606

Soil biodiversity and soil community composition determine ecosystem multifunctionality

PubMed Central

Wagg, Cameron; Bender, S. Franz; Widmer, Franco; van der Heijden, Marcel G. A.

2014-01-01

Biodiversity loss has become a global concern as evidence accumulates that it will negatively affect ecosystem services on which society depends. So far, most studies have focused on the ecological consequences of above-ground biodiversity loss; yet a large part of Earth’s biodiversity is literally hidden below ground. Whether reductions of biodiversity in soil communities below ground have consequences for the overall performance of an ecosystem remains unresolved. It is important to investigate this in view of recent observations that soil biodiversity is declining and that soil communities are changing upon land use intensification. We established soil communities differing in composition and diversity and tested their impact on eight ecosystem functions in model grassland communities. We show that soil biodiversity loss and simplification of soil community composition impair multiple ecosystem functions, including plant diversity, decomposition, nutrient retention, and nutrient cycling. The average response of all measured ecosystem functions (ecosystem multifunctionality) exhibited a strong positive linear relationship to indicators of soil biodiversity, suggesting that soil community composition is a key factor in regulating ecosystem functioning. Our results indicate that changes in soil communities and the loss of soil biodiversity threaten ecosystem multifunctionality and sustainability. PMID:24639507

Biological soil crusts as soil stabilizers: Chapter 16

USGS Publications Warehouse

Belnap, Jayne; Buedel, Burkhard; Weber, Bettina; Buedel, Burkhard; Belnap, Jayne

2016-01-01

Soil erosion is of particular concern in dryland regions, as the sparse cover of vascular plants results in large interspaces unprotected from the erosive forces of wind and water. Thus, most of these soil surfaces are stabilized by physical or biological soil crusts. However, as drylands are extensively used by humans and their animals, these crusts are often disturbed, compromising their stabilizing abilities. As a result, approximately 17.5% of the global terrestrial lands are currently being degraded by wind and water erosion. All components of biocrusts stabilize soils, including green algae, cyanobacteria, fungi, lichens, and bryophytes, and as the biomass of these organisms increases, so does soil stability. In addition, as lichens and bryophytes live atop the soil surface, they provide added protection from raindrop impact that cyanobacteria and fungi, living within the soil, cannot. Much research is still needed to determine the relative ability of individual species and suites of species to stabilize soils. We also need a better understanding of why some individuals or combination of species are better than others, especially as these organisms become more frequently used in restoration efforts.

Bioaugmentation of soil contaminated with high-level crude oil through inoculation with mixed cultures including Acremonium sp.

PubMed

Ma, Xiao-Kui; Ding, Ning; Peterson, Eric Charles

2015-06-01

Heavy contamination of soil with crude oil has caused significant negative environmental impacts and presents substantial hazards to human health. To explore a highly efficient bioaugmentation strategy for these contaminations, experiments were conducted over 180 days in soil heavily contaminated with crude oil (50,000 mg kg(-1)), with four treatments comprised of Bacillus subtilis inoculation with no further inoculation (I), or reinoculation after 100 days with either B. subtilis (II), Acremonium sp.(III), or a mixture of both organisms (IV). The removal values of total petroleum hydrocarbons were 60.1 ± 2.0, 60.05 ± 3.0, 71.3 ± 5.2 and 74.2 ± 2.7 % for treatment (I-IV), respectively. Treatments (III-IV) significantly enhanced the soil bioremediation compared with treatments (I-II) (p < 0.05). Furthermore, significantly (p < 0.05) greater rates of degradation for petroleum hydrocarbon fractions were observed in treatments (III-IV) compared to treatments (I-II), and this was especially the case with the degradative rates for polycyclic aromatic hydrocarbons and crude oil heavy fractions. Dehydrogenase activity in treatment (III-IV) containing Acremonium sp. showed a constant increase until the end of experiments. Therefore reinoculation with pure fungus or fungal-bacterial consortium should be considered as an effective strategy in bioaugmentation for soil heavily contaminated with crude oil.

Developing Intepretive Soil Education Displays.

ERIC Educational Resources Information Center

Hansmeyer, T. L.; Cooper, T. H.

1993-01-01

Describes several soil educational displays developed for park and nature center trails. Displays include full-scale soil monoliths displayed along the trails with explanations on why and how the soils are different, and micro-monoliths exhibiting the different soil types. (MDH)

Using soil temperature and moisture to predict forest soil nitrogen mineralization

Treesearch

Jennifer D. Knoepp; Wayne T. Swank

2002-01-01

Due to the importance of N in forest productivity ecosystem and nutrient cycling research often includes measurement of soil N transformation rates as indices of potential availability and ecosystem losses of N. We examined the feasibility of using soil temperature and moisture content to predict soil N mineralization rates (Nmin) at the Coweeta Hydrologic Laboratory...

Soils and the soil cover of the Valley of Geysers

NASA Astrophysics Data System (ADS)

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

2014-06-01

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 horizon—a thermometamorphic horizon TRM—can 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.

Container Soil-Water Reactions.

ERIC Educational Resources Information Center

Spomer, L. Art; Hershey, David R.

1990-01-01

Presented is an activity that illustrates the relationship between the soil found in containers and soil in the ground including the amount of air and water found in each. Sponges are used to represent soil. Materials, procedures, and probable results are described. (KR)

Electrokinetic electrode system for extraction of soil contaminants from unsaturated soils

DOEpatents

Lindgren, Eric R.; Mattson, Earl D.

1995-01-01

There is presented an electrokinetic electrode assembly for use in extraction of soil contaminants from unsaturated soil in situ. The assembly includes a housing for retaining a liquid comprising an electrolyte solution, pure water, and soil water, the housing being in part of porous material capable of holding a vacuum. An electrode is mounted in the housing. The housing is provided with a vacuum orifice for effecting a vacuum within the housing selectively to control flow of soil water through the housing into the chamber and to control outflow of the liquid from the chamber. The assembly further includes conduit means for removing the liquid from the housing and returning the electrolyte solution to the housing, and a conduit for admitting pure water to the housing. There is further presented an electrode system and method for extraction of soil contaminants, the system and method utilizing at least two electrode assemblies as described above.

Electrokinetic electrode system for extraction of soil contaminants from unsaturated soils

DOEpatents

Lindgren, E.R.; Mattson, E.D.

1995-07-25

An electrokinetic electrode assembly is described for use in extraction of soil contaminants from unsaturated soil in situ. The assembly includes a housing for retaining a liquid comprising an electrolyte solution, pure water, and soil water, the housing being in part of porous material capable of holding a vacuum. An electrode is mounted in the housing. The housing is provided with a vacuum orifice for effecting a vacuum within the housing selectively to control flow of soil water through the housing into the chamber and to control outflow of the liquid from the chamber. The assembly further includes conduit means for removing the liquid from the housing and returning the electrolyte solution to the housing, and a conduit for admitting pure water to the housing. An electrode system and method are also revealed for extraction of soil contaminants. The system and method utilize at least two electrode assemblies as described above. 5 figs.

Soil temperature, soil moisture and thaw depth, Barrow, Alaska, Ver. 1

DOE Data Explorer

Sloan, V.L.; J.A. Liebig; M.S. Hahn; J.B. Curtis; J.D. Brooks; A. Rogers; C.M. Iversen; R.J. Norby

2014-01-10

This dataset consists of field measurements of soil properties made during 2012 and 2013 in areas A-D of Intensive Site 1 at the Next-Generation Ecosystem Experiments (NGEE) Arctic site near Barrow, Alaska. Included are i) weekly measurements of thaw depth, soil moisture, presence and depth of standing water, and soil temperature made during the 2012 and 2013 growing seasons (June - September) and ii) half-hourly measurements of soil temperature logged continuously during the period June 2012 to September 2013.

Influence of site and soil properties on the DRIFT spectra of northern cold-region soils [Influence of site and soil properties on the mid-infrared spectra of northern cold-region soils

DOE PAGES

Matamala, Roser; Calderon, Francisco J.; Jastrow, Julie D.; ...

2017-06-05

Here, we investigated the influence of site characteristics and soil properties on the chemical composition of organic matter in soils collected from a latitudinal transect across Alaska through analysis of diffuse reflectance Fourier transform mid infrared (MidIR) spectra of bulk soils. The study included 119 soil samples collected from 28 sites including tundra, boreal forest, and grassland ecosystems. Organic, mineral, and cryoturbated soil horizons, both seasonally and perennially frozen, from a variety of depths and edaphic conditions were examined. The amount and chemical composition of organic matter as well as site and soil properties exerted a strong influence on themore » MidIR spectra. The spectra were highly sensitive to the extent of organic matter decomposition, enabling the ordination of Oi, Oe and Oa organic horizons. Differences in absorbance intensity for several spectral bands indicated that Oi horizons contained greater abundance of relatively fresh residues, phenolic-OH compounds, aliphatic compounds (waxes, lipids and fats), and carbohydrates. In contrast, Oa horizons had a greater presence of amide groups (possibly from microbial residues), aromatics, C=C bonds, carboxylates and carboxylic acids. Another significant factor differentiating these horizons was the incorporation of clays and silicates into the decomposing organic matter of Oa horizons. Calculated height peak ratios showed a clear trend to greater decomposition among Oi, Oe and Oa. The MidIR spectra were related to many site/soil attributes including land cover type, parent material, and associated factors, such as permafrost presence/absence, soil drainage, horizon depth, bulk density, cation exchange capacity, and pH. Single MidIR spectral bands were identified that might be used in future studies to quickly estimate the organic and inorganic carbon, total nitrogen, and carbon:nitrogen ratios of soils from northern latitudes. Lastly, our results demonstrate that the

Influence of site and soil properties on the DRIFT spectra of northern cold-region soils [Influence of site and soil properties on the mid-infrared spectra of northern cold-region soils

DOE Office of Scientific and Technical Information (OSTI.GOV)

Matamala, Roser; Calderon, Francisco J.; Jastrow, Julie D.

Here, we investigated the influence of site characteristics and soil properties on the chemical composition of organic matter in soils collected from a latitudinal transect across Alaska through analysis of diffuse reflectance Fourier transform mid infrared (MidIR) spectra of bulk soils. The study included 119 soil samples collected from 28 sites including tundra, boreal forest, and grassland ecosystems. Organic, mineral, and cryoturbated soil horizons, both seasonally and perennially frozen, from a variety of depths and edaphic conditions were examined. The amount and chemical composition of organic matter as well as site and soil properties exerted a strong influence on themore » MidIR spectra. The spectra were highly sensitive to the extent of organic matter decomposition, enabling the ordination of Oi, Oe and Oa organic horizons. Differences in absorbance intensity for several spectral bands indicated that Oi horizons contained greater abundance of relatively fresh residues, phenolic-OH compounds, aliphatic compounds (waxes, lipids and fats), and carbohydrates. In contrast, Oa horizons had a greater presence of amide groups (possibly from microbial residues), aromatics, C=C bonds, carboxylates and carboxylic acids. Another significant factor differentiating these horizons was the incorporation of clays and silicates into the decomposing organic matter of Oa horizons. Calculated height peak ratios showed a clear trend to greater decomposition among Oi, Oe and Oa. The MidIR spectra were related to many site/soil attributes including land cover type, parent material, and associated factors, such as permafrost presence/absence, soil drainage, horizon depth, bulk density, cation exchange capacity, and pH. Single MidIR spectral bands were identified that might be used in future studies to quickly estimate the organic and inorganic carbon, total nitrogen, and carbon:nitrogen ratios of soils from northern latitudes. Lastly, our results demonstrate that the

Modeling the Dynamics of Soil Structure and Water in Agricultural Soil

NASA Astrophysics Data System (ADS)

Weller, U.; Lang, B.; Rabot, E.; Stössel, B.; Urbanski, L.; Vogel, H. J.; Wiesmeier, M.; Wollschlaeger, U.

2017-12-01

The impact of agricultural management on soil functions is manifold and severe. It has both positive and adverse influence. Our goal is to develop model tools quantifying the agricultural impact on soil functions based on a mechanistic understanding of soil processes to support farmers and decision makers. The modeling approach is based on defining relevant soil components, i.e. soil matrix, macropores, organisms, roots and organic matter. They interact and form the soil's macroscopic properties and functions including water and gas dynamics, and biochemical cycles. Based on existing literature information we derive functional interaction processes and combine them in a network of dynamic soil components. In agricultural soils, a major issue is linked to changes in soil structure and their influence on water dynamics. Compaction processes are well studied in literature, but for the resilience due to root growth and activity of soil organisms the information is scarcer. We implement structural dynamics into soil water and gas simulations using a lumped model that is both coarse enough to allow extensive model runs while still preserving some important, yet rarely modeled phenomenons like preferential flow, hysteretic and dynamic behavior. For simulating water dynamics, at each depth, the model assumes water at different binding energies depending on soil structure, i.e. the pore size distribution. Non-equilibrium is postulated, meaning that free water may occur even if the soil is not fully saturated. All energy levels are interconnected allowing water to move, both within a spatial node, and between neighboring nodes (adding gravity). Structure dynamics alters the capacity of this water compartments, and the conductance of its connections. Connections are switched on and off depending on whether their sources contain water or their targets have free capacity. This leads to piecewise linear system behavior that allows fast calculation for extended time steps. Based

SoilInfo App: global soil information on your palm

NASA Astrophysics Data System (ADS)

Hengl, Tomislav; Mendes de Jesus, Jorge

2015-04-01

ISRIC ' World Soil Information has released in 2014 and app for mobile de- vices called 'SoilInfo' (http://soilinfo-app.org) and which aims at providing free access to the global soil data. SoilInfo App (available for Android v.4.0 Ice Cream Sandwhich or higher, and Apple v.6.x and v.7.x iOS) currently serves the Soil- Grids1km data ' a stack of soil property and class maps at six standard depths at a resolution of 1 km (30 arc second) predicted using automated geostatistical mapping and global soil data models. The list of served soil data includes: soil organic carbon (), soil pH, sand, silt and clay fractions (%), bulk density (kg/m3), cation exchange capacity of the fine earth fraction (cmol+/kg), coarse fragments (%), World Reference Base soil groups, and USDA Soil Taxonomy suborders (DOI: 10.1371/journal.pone.0105992). New soil properties and classes will be continuously added to the system. SoilGrids1km are available for download under a Creative Commons non-commercial license via http://soilgrids.org. They are also accessible via a Representational State Transfer API (http://rest.soilgrids.org) service. SoilInfo App mimics common weather apps, but is also largely inspired by the crowdsourcing systems such as the OpenStreetMap, Geo-wiki and similar. Two development aspects of the SoilInfo App and SoilGrids are constantly being worked on: Data quality in terms of accuracy of spatial predictions and derived information, and Data usability in terms of ease of access and ease of use (i.e. flexibility of the cyberinfrastructure / functionalities such as the REST SoilGrids API, SoilInfo App etc). The development focus in 2015 is on improving the thematic and spatial accuracy of SoilGrids predictions, primarily by using finer resolution covariates (250 m) and machine learning algorithms (such as random forests) to improve spatial predictions.

Should there be a "Wet" Soil Order in Soil Taxonomy?

NASA Astrophysics Data System (ADS)

Rabenhorst, Martin; Wessel, Barret; Stolt, Mark; Lindbo, David

2017-04-01

Early soil classification systems recognized wet soils at the highest categorical level. Among the Intrazonal Soils of the US classification utilized between the 1920s and 1960, were included as Great Soil Groups, the Wiesenboden, Bog, Half-Bog, Ground-Water Podzols and Ground-Water Laterites. In other systems, groups named with such terms as ground water gley and pseudogley were also used. With the advent of Soil Taxonomy and it's precursor (1960, 1975), Histosols (organic soils) were distinguished as one of the initial 10 soil orders, and while many of these organic soils are wet soils, some are not (Folists for example). Thus, for over 50 years, with the exception of Histosols, wet soils (which typically represent the wettest end of subaerial wet soils) have not been collectively recognized within taxa at the highest categorical level (order) in the US soil classification system. Rather, the wettest soils were designated at the second categorical level as wet (Aqu) suborders among the various soil orders, and more recently, subaqueous soils as "Wass" suborders of Entisols and Histosols. Soils with less-wet conditions have been recognized at the subgroup (4th) level. Further, in impoundments and regions of transgressing coastlines, submerged upland soils have been found that still classify in soil orders that do not accommodate subaqueous soils ("Wass" suborders). Notwithstanding, other contemporary soil classification systems do (have continued to) recognize wet soils at the highest level. In the World Reference Base (WRB) for example, wet soils are designated as Gleysols or Stagnosols. As efforts are underway to revisit, simplify, and revise Soil Taxonomy, questions have been raised regarding whether wet soils should again be moved back with a place among taxa at the highest category using a name such as Hydrasols, Aquasols, etc. This paper will explore and consider the questions and arguments for and against such proposals and the difficult question regarding

Soil fertility in deserts: a review on the influence of biological soil crusts and the effect of soil surface disturbance on nutrient inputs and losses

USGS Publications Warehouse

Reynolds, R.; Phillips, S.; Duniway, M.; Belnap, J.

2003-01-01

Sources of desert soil fertility include parent material weathering, aeolian deposition, and on-site C and N biotic fixation. While parent materials provide many soil nutrients, aeolian deposition can provide up to 75% of plant-essential nutrients including N, P, K, Mg, Na, Mn, Cu, and Fe. Soil surface biota are often sticky, and help retain wind-deposited nutrients, as well as providing much of the N inputs. Carbon inputs are from both plants and soil surface biota. Most desert soils are protected by cyanobacterial-lichen-moss soil crusts, chemical crusts and/or desert pavement. Experimental disturbances applied in US deserts show disruption of soil surfaces result in decreased N and C inputs from soil biota by up to 100%. The ability to glue aeolian deposits in place is compromised, and underlying soils are exposed to erosion. The ability to withstand wind increases with biological and physical soil crust development. While most undisturbed sites show little sediment production, disturbance by vehicles or livestock produce up to 36 times more sediment production, with soil movement initiated at wind velocities well below commonly-occurring wind speeds. Soil fines and flora are often concentrated in the top 3 mm of the soil surface. Winds across disturbed areas can quickly remove this material from the soil surface, thereby potentially removing much of current and future soil fertility. Thus, disturbances of desert soil surfaces can both reduce fertility inputs and accelerate fertility losses.

Soil degradation effect on biological activity in Mediterranean calcareous soils

NASA Astrophysics Data System (ADS)

Roca-Pérez, L.; Alcover-Sáez, S.; Mormeneo, S.; Boluda, R.

2009-04-01

Soil degradation processes include erosion, organic matter decline, compaction, salinization, landslides, contamination, sealing and biodiversity decline. In the Mediterranean region the climatological and lithological conditions, together with relief on the landscape and anthropological activity are responsible for increasing desertification process. It is therefore considered to be extreme importance to be able to measure soil degradation quantitatively. We studied soil characteristics, microbiological and biochemical parameters in different calcareous soil sequences from Valencia Community (Easter Spain), in an attempt to assess the suitability of the parameters measured to reflect the state of soil degradation and the possibility of using the parameters to assess microbiological decline and soil quality. For this purpose, forest, scrubland and agricultural soil in three soil sequences were sampled in different areas. Several sensors of the soil biochemistry and microbiology related with total organic carbon, microbial biomass carbon, soil respiration, microorganism number and enzyme activities were determined. The results show that, except microorganism number, these parameters are good indicators of a soil biological activity and soil quality. The best enzymatic activities to use like indicators were phosphatases, esterases, amino-peptidases. Thus, the enzymes test can be used as indicators of soil degradation when this degradation is related with organic matter losses. There was a statistically significant difference in cumulative O2 uptake and extracellular enzymes among the soils with different degree of degradation. We would like to thank Spanish government-MICINN for funding and support (MICINN, project CGL2006-09776).

[Interrelationships between soil fauna and soil environmental factors in China: research advance].

PubMed

Wang, Yi; Wei, Wei; Yang, Xing-zhong; Chen, Li-ding; Yang, Lei

2010-09-01

Soil fauna has close relations with various environmental factors in soil ecosystem. To explore the interrelationships between soil fauna and soil environmental factors is of vital importance to deep understand the dynamics of soil ecosystem and to assess the functioning of the ecosystem. The environmental factors affecting soil fauna can be classified as soil properties and soil external environment. The former contains soil basic physical and chemical properties, soil moisture, and soil pollution. The latter includes vegetation, land use type, landform, and climate, etc. From these aspects, this paper summarized the published literatures in China on the interrelationships between soil fauna and soil environmental factors. It was considered that several problems were existed in related studies, e.g., fewer researches were made in integrating soil fauna's bio-indicator function, research methods were needed to be improved, and the studies on the multi-environmental factors and their large scale spatial-temporal variability were in deficiency. Corresponding suggestions were proposed, i.e., more work should be done according to the practical needs, advanced experiences from abroad should be referenced, and comprehensive studies on multi-environmental factors and long-term monitoring should be conducted on large scale areas.

Exoenzyme activity in contaminated soils before and after soil washing: ß-glucosidase activity as a biological indicator of soil health.

PubMed

Chae, Yooeun; Cui, Rongxue; Woong Kim, Shin; An, Gyeonghyeon; Jeong, Seung-Woo; An, Youn-Joo

2017-01-01

It is essential to remediate or amend soils contaminated with various heavy metals or pollutants so that the soils may be used again safely. Verifying that the remediated or amended soils meet soil quality standards is an important part of the process. We estimated the activity levels of eight soil exoenzymes (acid phosphatase, arylsulfatase, catalase, dehydrogenase, fluorescein diacetate hydrolase, protease, urease, and ß-glucosidase) in contaminated and remediated soils from two sites near a non-ferrous metal smelter, using colorimetric and titrimetric determination methods. Our results provided the levels of activity of soil exoenzymes that indicate soil health. Most enzymes showed lower activity levels in remediated soils than in contaminated soils, with the exception of protease and urease, which showed higher activity after remediation in some soils, perhaps due to the limited nutrients available in remediated soils. Soil exoenzymes showed significantly higher activity in soils from one of the sites than from the other, due to improper conditions at the second site, including high pH, poor nutrient levels, and a high proportion of sand in the latter soil. Principal component analysis revealed that ß-glucosidase was the best indicator of soil ecosystem health, among the enzymes evaluated. We recommend using ß-glucosidase enzyme activity as a prior indicator in estimating soil ecosystem health. Copyright © 2016 Elsevier Inc. All rights reserved.

30 CFR 823.14 - Soil replacement.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 30 Mineral Resources 3 2013-07-01 2013-07-01 false Soil replacement. 823.14 Section 823.14 Mineral... Soil replacement. (a) Soil reconstruction specifications established by the U.S. Soil Conservation Service shall be based upon the standards of the National Cooperative Soil Survey and shall include, as a...

30 CFR 823.14 - Soil replacement.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Soil replacement. 823.14 Section 823.14 Mineral... Soil replacement. (a) Soil reconstruction specifications established by the U.S. Soil Conservation Service shall be based upon the standards of the National Cooperative Soil Survey and shall include, as a...

30 CFR 823.14 - Soil replacement.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 30 Mineral Resources 3 2014-07-01 2014-07-01 false Soil replacement. 823.14 Section 823.14 Mineral... Soil replacement. (a) Soil reconstruction specifications established by the U.S. Soil Conservation Service shall be based upon the standards of the National Cooperative Soil Survey and shall include, as a...

30 CFR 823.14 - Soil replacement.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 30 Mineral Resources 3 2012-07-01 2012-07-01 false Soil replacement. 823.14 Section 823.14 Mineral... Soil replacement. (a) Soil reconstruction specifications established by the U.S. Soil Conservation Service shall be based upon the standards of the National Cooperative Soil Survey and shall include, as a...

30 CFR 823.14 - Soil replacement.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 30 Mineral Resources 3 2011-07-01 2011-07-01 false Soil replacement. 823.14 Section 823.14 Mineral... Soil replacement. (a) Soil reconstruction specifications established by the U.S. Soil Conservation Service shall be based upon the standards of the National Cooperative Soil Survey and shall include, as a...

Monitoring well

DOEpatents

Hubbell, Joel M.; Sisson, James B.

2002-01-01

The present invention relates to a monitoring well which includes an enclosure defining a cavity and a water reservoir enclosed within the cavity and wherein the reservoir has an inlet and an outlet. The monitoring well further includes a porous housing borne by the enclosure and which defines a fluid chamber which is oriented in fluid communication with the outlet of the reservoir, and wherein the porous housing is positioned in an earthen soil location below-grade. A geophysical monitoring device is provided and mounted in sensing relation relative to the fluid chamber of the porous housing; and a coupler is selectively moveable relative to the outlet of reservoir to couple the porous housing and water reservoir in fluid communication. An actuator is coupled in force transmitting relation relative to the coupler to selectively position the coupler in a location to allow fluid communication between the reservoir and the fluid chamber defined by the porous housing.

Soil tension mediates isotope fractionation during soil water evaporation

NASA Astrophysics Data System (ADS)

Gaj, Marcel; McDonnell, Jeffrey

2017-04-01

Isotope tracing of the water cycle is increasing in its use and usefulness. Many new studies are extracting soil waters and relating these to streamflow, groundwater recharge and plant transpiration. Nevertheless, unlike isotope fractionation factors from open water bodies, soil water fractionation factors are poorly understood and until now, only empirically derived. In contrast to open water evaporation where temperature, humidity and vapor pressure gradient define fractionation (as codified in the well-known Craig and Gordon model), soil water evaporation includes additionally, fractionation by matrix effects. There is yet no physical explanation of kinetic and equilibrium fraction from soil water within the soil profile. Here we present a simple laboratory experiment with four admixtures of soil grain size (from sand to silt to clay). Oven-dried samples were spiked with water of known isotopic composition at different soil water contents. Soils were then stored in sealed bags and the headspace filled with dry air and allowed to equilibrate for 24hours. Isotopic analysis of the headspace vapor was done with a Los Gatos Inc. water vapor isotope analyzer. Soil water potential of subsamples were measured with a water potential meter. We show for the first time that soil tension controls isotope fractionation in the resident soil water. Below a Pf 3.5 the δ-values of 18O and 2H of the headspace vapor is more positive and increases with increasing soil water potential. Surprisingly, we find that the relationship between soil tension and equilibrium fractionation is independent of soil type. However, δ-values of each soil type plot along a distinct evaporation line. These results indicate that equilibrium fractionation is affected by soil tension in addition to temperature. Therefore, at high soil water tension (under dry conditions) equilibrium fractionation is not consistent with current empirical formulations that ignore these effects. These findings may have

Soil formation: Chapter 6

USGS Publications Warehouse

Goldhaber, Martin B.; Banwart, Steven A.

2015-01-01

Soil formation reflects the complex interaction of many factors, among the most important of which are (i) the nature of the soil parent material, (ii) regional climate, (iii) organisms, including humans, (iv) topography and (v) time. These processes operate in Earth's critical zone; the thin veneer of our planet where rock meets life. Understanding the operation of these soil-forming factors requires an interdisciplinary approach and is a necessary predicate to charactering soil processes and functions, mitigating soil degradation and adapting soil management to environmental change. In this chapter, we discuss how these soil-forming factors operate both singly and in concert in natural and human modified environments. We emphasize the role that soil organic matter plays in these processes to provide context for understanding the benefits that it bestows on humanity.

Increasing Efficiency of Water Use in Agriculture through Management of Soil Water Repellency to Optimize Soil and Water Productivity

NASA Astrophysics Data System (ADS)

Moore, Demie; Kostka, Stan; McMillan, Mica; Gadd, Nick

2010-05-01

Water's ability to infiltrate and disperse in soils, and soil's ability to receive, transport, retain, filter and release water are important factors in the efficient use of water in agriculture. Deteriorating soil conditions, including development of soil water repellency, negatively impact hydrological processes and, consequently, the efficiency of rainfall and irrigation. Soil water repellency is increasingly being identified in diverse soils and cropping systems. Recently research has been conducted on the use of novel soil surfactants (co-formulations of alkyl polyglycoside and block copolymer surfactants) to avoid or overcome soil water repellency and enhance water distribution in soils. Results indicate that this is an effective and affordable approach to maintaining or restoring soil and water productivity in irrigated cropping systems. Results from studies conducted in Australia and the United States to determine how this technology modifies soil hydrological behavior and crop yields will be presented. A range of soils and various crops, including potatoes, corn, apples and grapes, were included. Several rates were compared to controls for effect on soil moisture levels, soil water distribution, and crop yield. An economic analysis was also conducted in some trials. Treatments improved rootzone water status, significantly increased crop yield and quality, and in some cases allowed significant reductions in water requirements. Where assessed, a positive economic return was generated. This technology holds promise as a strategy for increasing efficiency of water use in agriculture.

Agriculture Canada Central Saskatchewan Vector Soils Data

NASA Technical Reports Server (NTRS)

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

2000-01-01

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.

Soil and Litter Animals.

ERIC Educational Resources Information Center

Lippert, George

1991-01-01

A lesson plan for soil study utilizes the Tullgren extraction method to illustrate biological concepts. It includes background information, equipment, collection techniques, activities, and references for identification guides about soil fauna. (MCO)

Latent Heat in Soil Heat Flux Measurements

USDA-ARS?s Scientific Manuscript database

The surface energy balance includes a term for soil heat flux. Soil heat flux is difficult to measure because it includes conduction and convection heat transfer processes. Accurate representation of soil heat flux is an important consideration in many modeling and measurement applications. Yet, the...

Predicting Soluble Nickel in Soils Using Soil Properties and Total Nickel.

PubMed

Zhang, Xiaoqing; Li, Jumei; Wei, Dongpu; Li, Bo; Ma, Yibing

2015-01-01

Soil soluble nickel (Ni) concentration is very important for determining soil Ni toxicity. In the present study, the relationships between soil properties, total and soluble Ni concentrations in soils were developed in a wide range of soils with different properties and climate characteristics. The multiple regressions showed that soil pH and total soil Ni concentrations were the most significant parameters in predicting soluble Ni concentrations with the adjusted determination coefficients (Radj2) values of 0.75 and 0.68 for soils spiked with soluble Ni salt and the spiked soils leached with artificial rainwater to mimic field conditions, respectively. However, when the soils were divided into three categories (pH < 7, 7-8 and > 8), they obtained better predictions with Radj2 values of 0.78-0.90 and 0.79-0.94 for leached and unleached soils, respectively. Meanwhile, the other soil properties, such as amorphous Fe and Al oxides and clay, were also found to be important for determining soluble Ni concentrations, indicating that they were also presented as active adsorbent surfaces. Additionally, the whole soil speciation including bulk soil properties and total soils Ni concentrations were analyzed by mechanistic speciation models WHAM VI and Visual MINTEQ3.0. It was found that WHAM VI provided the best predictions for the soils with pH < 7, was relatively reasonable for pH 7 to 8, and gave an overestimation for pH > 8. The Visual MINTEQ3.0 could provide better estimation for pH < 8 and meanwhile quite reasonable results for pH > 8. These results indicated the possibility and applicability of these models to predict soil soluble Ni concentration by soil properties.

[Effects of soil trituration size on adsorption of oxytetracycline on soils].

PubMed

Qi, Rui-Huan; Li, Zhao-Jun; Long, Jian; Fan, Fei-Fei; Liang, Yong-Chao

2011-02-01

In order to understand the effects of soil trituration size on adsorption of oxytetracycline (OTC) on soils, two contrasting soils including moisture soil and purplish soil were selected to investigate adsorption of OTC on these soils, at the scales of no more than 0.20 mm, 0.84 mm, 0.25 mm and 0.15 mm, using the method of batch equilibrium experiments respectively. The results presented as the following: (1) Adsorption amount of OTC on moisture soil and purplish soil increased with the sampling time, and reached to equilibration at 24 h. First-order kinetic model, second-order kinetic model, parabolic-diffusion kinetic model, Elovich kinetic model, and two-constant kinetic model could be used to fit the changes in adsorption on soils with sampling time. Adsorption of OTC on two soils consisted of two processes such as quick adsorption and slow adsorption. Quick adsorption process happened during the period of 0-0.5 h. The adsorption rates of OTC on soils were higher at the small trituration size than those at the large trituration size, and at the same trituration size, the k(f) of purplish soil was about two times higher than those of moisture soil. (2) Adsorption isotherms of OTC on two soils with different trituration sizes were deviated from the linear model. The data were fitted well to Freundlich and Langmuir models, with the correlation coefficients between 0.956 and 0.999. The values of k(f) and q(m) for purplish soil were higher than those for moisture soil. At the same soil, adsorption amount of OTC increased with the decreases of soil trituration size. The results suggested that it is important to select the appropriate trituration size, based on the physical and chemical properties such as soil particle composition and so on, when the fate of antibiotics on soils was investigated.

Microbial community structure and abundance in the rhizosphere and bulk soil of a tomato cropping system that includes cover crops

USDA-ARS?s Scientific Manuscript database

In this report we use Terminal Restriction Fragment Length Polymorphisms (TRFLP) in a tomato production system to “finger printing” the soil microbial community structure with Phylum specific primer sets. Factors influencing the soil microbes are a cover crop of Hairy Vetch (Vicia villosa) or Rye (...

Human relations with soil are changing rapidly: SSSA's new Work Group on Soil Change

USDA-ARS?s Scientific Manuscript database

Humanity has rapidly become Earth’s chief agent of soil change, and geologists have named the epoch in which we live the Anthropocene, due to the global scale of human impact on the environment, including soil. In response to the increasing influence of humans on soil processes, the disciplines of ...

Soil salination indicators

USDA-ARS?s Scientific Manuscript database

Salts are naturally present in soils, and many salt elements are essential nutrients for plants. The most common soluble salts in soil include major cations of sodium (Na+), magnesium (Mg2+), calcium (Ca2+), potassium (K+), and anions of chloride (Cl-), sulfate (SO42-), bicarbonate (HCO3-) and carbo...

Soil cover of gas-bearing areas

NASA Astrophysics Data System (ADS)

Mozharova, N. V.

2010-08-01

Natural soils with disturbed functioning parameters compared to the background soils with conservative technogenic-pedogenic features were distinguished on vast areas above the artificial underground gas storages in the zones of spreading and predominant impact of hydrocarbon gases. The disturbance of the functioning parameters is related to the increase in the methane concentration, the bacterial oxidation intensity and destruction, and the complex microbiological and physicochemical synthesis of iron oxides. The technogenic-pedogenic features include neoformations of bacteriomorphic microdispersed iron oxides. The impurity components consist of elements typical for biogenic structures. New soil layers, horizons, specific anthropogenically modified soils, and soil-like structures were formed on small areas in the industrial zones of underground gas storages due to the mechanical disturbance, the deposition of drilling sludge, and the chemical contamination. Among the soils, postlithogenic formations were identified—chemotechnosols (soddy-podzolic soils and chernozems), as well as synlithogenic ones: strato-chemotechnosols and stratochemoembryozems. The soil-like bodies included postlithogenic soil-like structures (chemotechnozems) and synlithogenic ones (strato-chemotechnozems). A substantive approach was used for the soil diagnostics. The morphological and magnetic profiles and the physical, chemical, and physicochemical properties of the soils were analyzed. The micromorphological composition of the soil magnetic fraction was used as a magnetic label.

Soil management: The key to soil quality and sustainable agriculture

NASA Astrophysics Data System (ADS)

Basch, Gottlieb; Barão, Lúcia; Soares, Miguel

2017-04-01

Today, after the International Year of Soils in 2015 and the proclamation by the International Union of Soil Sciences of the International Decade of Soils 2015-2020, much attention is paid to soil quality. Often used interchangeably, both terms, soil quality and soil health, refer to dynamic soil properties such as soil organic matter or pH, while soil quality also includes inherent soil properties such as texture or mineral composition. However, it is the dynamic or manageable properties that adequate soil management can influence and thus contribute to a well-functioning soil environment capable to deliver the soil-mediated provisioning, regulating and supporting ecosystem services and soil functions. This contribution intends to highlight the key principles of sustainable soil management and provide evidence that they are compliant with a productive, resource efficient and ecologically friendly agriculture. Paradoxically, and despite benefitting from good soil quality, agriculture itself when based on conventional, especially intensive tillage-based soil management practices contributes decisively to soil degradation and to several of the soil threats as identified by the Soil Thematic Strategy, being soil erosion and soil organic matter decline the most notorious ones. To mitigate soil degradation, the European Union's Common Agricultural Policy has introduced conservation measures, mainly through cross-compliance measures supposed to guarantee minimum soil cover, to limit soil erosion and to maintain the levels of soil organic matter. However, it remains unclear to what extent EU member states apply these 'Good Agricultural and Environmental Condition' (GAEC) measures to their utilized agricultural areas. Effective and cost-efficient soil management systems able to conserve or to restore favourable soil conditions, to minimize soil erosion and to invert soil organic matter and soil biodiversity decline and improve soil structure are those capable to mimic as

Predicting Soluble Nickel in Soils Using Soil Properties and Total Nickel

PubMed Central

Zhang, Xiaoqing; Li, Jumei; Wei, Dongpu; Li, Bo; Ma, Yibing

2015-01-01

Soil soluble nickel (Ni) concentration is very important for determining soil Ni toxicity. In the present study, the relationships between soil properties, total and soluble Ni concentrations in soils were developed in a wide range of soils with different properties and climate characteristics. The multiple regressions showed that soil pH and total soil Ni concentrations were the most significant parameters in predicting soluble Ni concentrations with the adjusted determination coefficients (Radj 2) values of 0.75 and 0.68 for soils spiked with soluble Ni salt and the spiked soils leached with artificial rainwater to mimic field conditions, respectively. However, when the soils were divided into three categories (pH < 7, 7–8 and > 8), they obtained better predictions with Radj 2 values of 0.78–0.90 and 0.79–0.94 for leached and unleached soils, respectively. Meanwhile, the other soil properties, such as amorphous Fe and Al oxides and clay, were also found to be important for determining soluble Ni concentrations, indicating that they were also presented as active adsorbent surfaces. Additionally, the whole soil speciation including bulk soil properties and total soils Ni concentrations were analyzed by mechanistic speciation models WHAM VI and Visual MINTEQ3.0. It was found that WHAM VI provided the best predictions for the soils with pH < 7, was relatively reasonable for pH 7 to 8, and gave an overestimation for pH > 8. The Visual MINTEQ3.0 could provide better estimation for pH < 8 and meanwhile quite reasonable results for pH > 8. These results indicated the possibility and applicability of these models to predict soil soluble Ni concentration by soil properties. PMID:26217951

Impacts of soil moisture content on visual soil evaluation

NASA Astrophysics Data System (ADS)

Emmet-Booth, Jeremy; Forristal, Dermot; Fenton, Owen; Bondi, Giulia; Creamer, Rachel; Holden, Nick

2017-04-01

Visual Soil Examination and Evaluation (VSE) techniques offer tools for soil quality assessment. They involve the visual and tactile assessment of soil properties such as aggregate size and shape, porosity, redox morphology, soil colour and smell. An increasing body of research has demonstrated the reliability and utility of VSE techniques. However a number of limitations have been identified, including the potential impact of soil moisture variation during sampling. As part of a national survey of grassland soil quality in Ireland, an evaluation of the impact of soil moisture on two widely used VSE techniques was conducted. The techniques were Visual Evaluation of Soil Structure (VESS) (Guimarães et al., 2011) and Visual Soil Assessment (VSA) (Shepherd, 2009). Both generate summarising numeric scores that indicate soil structural quality, though employ different scoring mechanisms. The former requires the assessment of properties concurrently and the latter separately. Both methods were deployed on 20 sites across Ireland representing a range of soils. Additional samples were taken for soil volumetric water (θ) determination at 5-10 and 10-20 cm depth. No significant correlation was observed between θ 5-10 cm and either VSE technique. However, VESS scores were significantly related to θ 10-20 cm (rs = 0.40, sig = 0.02) while VSA scores were not (rs = -0.33, sig = 0.06). VESS and VSA scores can be grouped into quality classifications (good, moderate and poor). No significant mean difference was observed between θ 5-10 cm or θ 10-20 cm according to quality classification by either method. It was concluded that VESS scores may be affected by soil moisture variation while VSA appear unaffected. The different scoring mechanisms, where the separate assessment and scoring of individual properties employed by VSA, may limit soil moisture effects. However, moisture content appears not to affect overall structural quality classification by either method. References

Soil Management Effects on Gas Fluxes from an Organic Soil Agricultural System

NASA Astrophysics Data System (ADS)

Jennewein, S. P.; Bhadha, J. H.; Lang, T. A.; Singh, M.; Daroub, S. H.; McCray, M.

2015-12-01

The role of soil management on gas flux isn't well understood for Histosols of the Everglades Agricultural Area (EAA) of southern Florida. The region is responsible for roughly half of sugarcane (Saccharum spp. hybrids) production in the USA along with supplying winter vegetable crops to the eastern USA. Future productivity in the EAA is jeopardized by soil subsidence resulting from oxidation of organic matter. Establishing the role of tillage, water-table depth, nitrogen fertilizer, and soil depth on gas flux will help determine how effective various managements are on conserving soil. Ongoing lysimeter and field studies examined effects of management practices (water-table, tillage, and nitrogen fertilizer), and soil depth on, gas emission and microbial biomass. The trials were set in Belle Glade, FL, on Lauderhill muck (Lithic Haplosaprists). Results to be presented include soil microbial biomass and soil gas (CO2, CH4, and N2O) flux. This study provides insight into management effectiveness and agriculture sustainability on shallow muck soils of the EAA and will help farmers mitigate problems associated with soil subsidence and seasonally high water-tables.

Effect of management and soil moisture regimes on wetland soils total carbon and nitrogen in Tanzania

NASA Astrophysics Data System (ADS)

Kamiri, Hellen; Kreye, Christine; Becker, Mathias

2013-04-01

Wetland soils play an important role as storage compartments for water, carbon and nutrients. These soils implies various conditions, depending on the water regimes that affect several important microbial and physical-chemical processes which in turn influence the transformation of organic and inorganic components of nitrogen, carbon, soil acidity and other nutrients. Particularly, soil carbon and nitrogen play an important role in determining the productivity of a soil whereas management practices could determine the rate and magnitude of nutrient turnover. A study was carried out in a floodplain wetland planted with rice in North-west Tanzania- East Africa to determine the effects of different management practices and soil water regimes on paddy soil organic carbon and nitrogen. Four management treatments were compared: (i) control (non weeded plots); (ii) weeded plots; (iii) N fertilized plots, and (iv) non-cropped (non weeded plots). Two soil moisture regimes included soil under field capacity (rainfed conditions) and continuous water logging compared side-by-side. Soil were sampled at the start and end of the rice cropping seasons from the two fields differentiated by moisture regimes during the wet season 2012. The soils differed in the total organic carbon and nitrogen between the treatments. Soil management including weeding and fertilization is seen to affect soil carbon and nitrogen regardless of the soil moisture conditions. Particularly, the padddy soils were higher in the total organic carbon under continuous water logged field. These findings are preliminary and a more complete understanding of the relationships between management and soil moisture on the temporal changes of soil properties is required before making informed decisions on future wetland soil carbon and nitrogen dynamics. Keywords: Management, nitrogen, paddy soil, total carbon, Tanzania,

Large-extent digital soil mapping approaches for total soil depth

NASA Astrophysics Data System (ADS)

Mulder, Titia; Lacoste, Marine; Saby, Nicolas P. A.; Arrouays, Dominique

2015-04-01

Total soil depth (SDt) plays a key role in supporting various ecosystem services and properties, including plant growth, water availability and carbon stocks. Therefore, predictive mapping of SDt has been included as one of the deliverables within the GlobalSoilMap project. In this work SDt was predicted for France following the directions of GlobalSoilMap, which requires modelling at 90m resolution. This first method, further referred to as DM, consisted of modelling the deterministic trend in SDt using data mining, followed by a bias correction and ordinary kriging of the residuals. Considering the total surface area of France, being about 540K km2, employed methods may need to be able dealing with large data sets. Therefore, a second method, multi-resolution kriging (MrK) for large datasets, was implemented. This method consisted of modelling the deterministic trend by a linear model, followed by interpolation of the residuals. For the two methods, the general trend was assumed to be explained by the biotic and abiotic environmental conditions, as described by the Soil-Landscape paradigm. The mapping accuracy was evaluated by an internal validation and its concordance with previous soil maps. In addition, the prediction interval for DM and the confidence interval for MrK were determined. Finally, the opportunities and limitations of both approaches were evaluated. The results showed consistency in mapped spatial patterns and a good prediction of the mean values. DM was better capable in predicting extreme values due to the bias correction. Also, DM was more powerful in capturing the deterministic trend than the linear model of the MrK approach. However, MrK was found to be more straightforward and flexible in delivering spatial explicit uncertainty measures. The validation indicated that DM was more accurate than MrK. Improvements for DM may be expected by predicting soil depth classes. MrK shows potential for modelling beyond the country level, at high

Underestimation of boreal soil carbon stocks by mathematical soil carbon models linked to soil nutrient status

NASA Astrophysics Data System (ADS)

Ťupek, Boris; Ortiz, Carina A.; Hashimoto, Shoji; Stendahl, Johan; Dahlgren, Jonas; Karltun, Erik; Lehtonen, Aleksi

2016-08-01

Inaccurate estimate of the largest terrestrial carbon pool, soil organic carbon (SOC) stock, is the major source of uncertainty in simulating feedback of climate warming on ecosystem-atmosphere carbon dioxide exchange by process-based ecosystem and soil carbon models. Although the models need to simplify complex environmental processes of soil carbon sequestration, in a large mosaic of environments a missing key driver could lead to a modeling bias in predictions of SOC stock change.We aimed to evaluate SOC stock estimates of process-based models (Yasso07, Q, and CENTURY soil sub-model v4) against a massive Swedish forest soil inventory data set (3230 samples) organized by a recursive partitioning method into distinct soil groups with underlying SOC stock development linked to physicochemical conditions.For two-thirds of measurements all models predicted accurate SOC stock levels regardless of the detail of input data, e.g., whether they ignored or included soil properties. However, in fertile sites with high N deposition, high cation exchange capacity, or moderately increased soil water content, Yasso07 and Q models underestimated SOC stocks. In comparison to Yasso07 and Q, accounting for the site-specific soil characteristics (e. g. clay content and topsoil mineral N) by CENTURY improved SOC stock estimates for sites with high clay content, but not for sites with high N deposition.Our analysis suggested that the soils with poorly predicted SOC stocks, as characterized by the high nutrient status and well-sorted parent material, indeed have had other predominant drivers of SOC stabilization lacking in the models, presumably the mycorrhizal organic uptake and organo-mineral stabilization processes. Our results imply that the role of soil nutrient status as regulator of organic matter mineralization has to be re-evaluated, since correct SOC stocks are decisive for predicting future SOC change and soil CO2 efflux.

Plants as sources of airborne bacteria, including ice nucleation-active bacteria.

PubMed

Lindemann, J; Constantinidou, H A; Barchet, W R; Upper, C D

1982-11-01

Vertical wind shear and concentration gradients of viable, airborne bacteria were used to calculate the upward flux of viable cells above bare soil and canopies of several crops. Concentrations at soil or canopy height varied from 46 colony-forming units per m over young corn and wet soil to 663 colony-forming units per m over dry soil and 6,500 colony-forming units per m over a closed wheat canopy. In simultaneous samples, concentrations of viable bacteria in the air 10 m inside an alfalfa field were fourfold higher than those over a field with dry, bare soil immediately upwind. The upward flux of viable bacteria over alfalfa was three- to fourfold greater than over dry soil. Concentrations of ice nucleation-active bacteria were higher over plants than over soil. Thus, plant canopies may constitute a major source of bacteria, including ice nucleation-active bacteria, in the air.

Soil ecology of a rock outcrop ecosystem: Abiotic stresses, soil respiration, and microbial community profiles in limestone cedar glades

USGS Publications Warehouse

Cartwright, Jennifer M.; Advised by Dzantor, E. Kudjo

2015-01-01

Stress factors quantified by this research include shallow soil (depth to bedrock ranging from 2.4 to 22.6 cm), volumetric soil water content levels seasonally ranging from xeric (below 5%) to saturated (above 50%), and seasonally extreme ground-surface temperatures (above 48°C). Findings from this research indicate that spatial and temporal heterogeneity exists in limestone cedar glades in terms of abiotic stress factors and soil physical and chemical properties. Several such soil properties (e.g. soil depth, organic matter levels, pH, and particle size distribution) are spatially correlated. These soil properties were statistically related to ecological structures and functions such as vegetation patterns, soil respiration, the density of culturable heterotrophic microbes in soil and metabolic diversity of soil microbial community profiles. In general, zones within limestone cedar glades that had relatively shallow soil, alkaline pH, low levels of organic matter and high levels of silt also tended to have depressed rates of soil respiration and reduced densities and metabolic diversity of culturable heterotrophic soil microbes. Additionally, seasonally-relevant stress factors including soil water content and temperatures at or near the soil surface were related to the same set of ecological structures and functions.

SOLVENT EXTRACTION AND SOIL WASHING TREATMENT OF CONTAMINATED SOILS FROM WOOD PRESERVING SITES: BENCH SCALE STUDIES

EPA Science Inventory

Bench-scale solvent extraction and soil washing studies were performed on soil samples obtained from three abandoned wood preserving sites that included in the NPL. The soil samples from these sites were contaminated with high levels of polyaromatic hydrocarbons (PAHs), pentachlo...

Drivers of soil organic matter vulnerability to climate change, Part II: RothC modelling of carbon dynamics including radiocarbon data

NASA Astrophysics Data System (ADS)

Studer, Mirjam S.; Abiven, Samuel; González Domínguez, Beatriz R.; Hagedorn, Frank; Reisser, Moritz; Walthert, Lorenz; Zimmermann, Stephan; Niklaus, Pascal A.

2016-04-01

It is still largely unknown what drives the vulnerability of soil organic carbon (SOC) stocks to climate change, i.e. the likelihood of a soil to loose its SOC along with the change in environmental conditions. Our objective is to assess the SOC vulnerability of Swiss forest soils and identify its potential drivers: climate (temperature, soil moisture), soil (clay content, pH) and landscape (slope, aspect) properties. Fifty-four sites were selected for balanced spatial and driver magnitudes distribution. We measured the SOC characteristics (content and radiocarbon) and studied the C decomposition by laboratory soil incubations (details in Part I, abstract by B. González Domínguez). In order to assess the current SOC pool distribution and its radiocarbon signatures, we extended the Rothamsted Carbon (RothC) model with radiocarbon (14C) isotope modelling (RothCiso). The RothC model distinguishes four active SOC pools, decomposable and resistant plant material, microbial biomass and humified organic matter, and an inert SOC pool (Jenkinson 1990). The active pools are decomposed and mineralized to CO2 by first order kinetics. The RothCiso assigns all pools a 14C signature, based on the atmospheric 14C concentrations of the past century (plant C inputs) and their turnover. Currently we constrain the model with 14C signatures measured on the 54 fresh and their corresponding archived bulk soil samples, taken 12-24 years before. We were able to reproduce the measured radiocarbon concentrations of the SOC with the RothCiso and first results indicate, that the assumption of an inert SOC pool, that is radiocarbon dead, is not appropriate. In a second step we will compare the SOC mean residence time assessed by the two methodological approaches - incubation (C efflux based) and modelling (C stock based) - and relate it to the environmental drivers mentioned above. With the combination of the two methodological approaches and 14C analysis we hope to gain more insights into

What are Soil Fumigants?

EPA Pesticide Factsheets

These pesticides, when applied to soil, form a gas to control pests including nematodes, fungi, bacteria, insects, and weeds, that live in the soil and can disrupt plant growth and crop production. Required safety measures reduce exposure risks.

Climate Change, Soils, and Human Health

NASA Astrophysics Data System (ADS)

Brevik, Eric C.

2013-04-01

According to the Intergovernmental Panel on Climate Change, global temperatures are expected to increase 1.1 to 6.4 degrees C during the 21st century and precipitation patterns will be altered by climate change (IPCC, 2007). Soils are intricately linked to the atmospheric/climate system through the carbon, nitrogen, and hydrologic cycles. Altered climate will, therefore, have an effect on soil processes and properties. Studies into the effects of climate change on soil processes and properties are still incomplete, but have revealed that climate change will impact soil organic matter dynamics including soil organisms and the multiple soil properties that are tied to organic matter, soil water, and soil erosion. The exact direction and magnitude of those impacts will be dependent on the amount of change in atmospheric gases, temperature, and precipitation amounts and patterns. Recent studies give reason to believe at least some soils may become net sources of atmospheric carbon as temperatures rise; this is particularly true of high latitude regions with permanently frozen soils. Soil erosion by both wind and water is also likely to increase. These soil changes will lead to both direct and indirect impacts on human health. Possible indirect impacts include temperature extremes, food safety and air quality issues, increased and/or expanded disease incidences, and occupational health issues. Potential direct impacts include decreased food security and increased atmospheric dust levels. However, there are still many things we need to know more about. How climate change will affect the nitrogen cycle and, in turn, how the nitrogen cycle will affect carbon sequestration in soils is a major research need, as is a better understanding of soil water-CO2 level-temperature relationships. Knowledge of the response of plants to elevated atmospheric CO2 given limitations in nutrients like nitrogen and phosphorus and how that affects soil organic matter dynamics is a critical

Soil aggregate and organic carbon distribution at dry land soil and paddy soil: the role of different straws returning.

PubMed

Huang, Rong; Lan, Muling; Liu, Jiang; Gao, Ming

2017-12-01

Agriculture wastes returning to soil is one of common ways to reuse crop straws in China. The returned straws are expected to improve the fertility and structural stability of soil during the degradation of straw it selves. The in situ effect of different straw (wheat, rice, maize, rape, and broad bean) applications for soil aggregate stability and soil organic carbon (SOC) distribution were studied at both dry land soil and paddy soil in this study. Wet sieving procedures were used to separate soil aggregate sizes. Aggregate stability indicators including mean weight diameter, geometric mean diameter, mean weight of specific surface area, and the fractal dimension were used to evaluate soil aggregate stability after the incubation of straws returning. Meanwhile, the variation and distribution of SOC in different-sized aggregates were further studied. Results showed that the application of straws, especially rape straw at dry land soil and rice straw at paddy soil, increased the fractions of macro-aggregate (> 0.25 mm) and micro-aggregate (0.25-0.053 mm). Suggesting the nutrients released from straw degradation promotes the growing of soil aggregates directly and indirectly. The application of different straws increased the SOC content at both soils and the SOC mainly distributed at < 0.53 mm aggregates. However, the contribution of SOC in macro- and micro-aggregates increased. Straw-applied paddy soil have a higher total SOC content but lower SOC contents at > 0.25 and 0.25-0.053 mm aggregates with dry land soil. Rape straw in dry land and rice straw in paddy field could stabilize soil aggregates and increasing SOC contents best.

Accessibility, searchability, transparency and engagement of soil carbon data: The International Soil Carbon Network

NASA Astrophysics Data System (ADS)

Harden, Jennifer W.; Hugelius, Gustaf; Koven, Charlie; Sulman, Ben; O'Donnell, Jon; He, Yujie

2016-04-01

Soils are capacitors for carbon and water entering and exiting through land-atmosphere exchange. Capturing the spatiotemporal variations in soil C exchange through monitoring and modeling is difficult in part because data are reported unevenly across spatial, temporal, and management scales and in part because the unit of measure generally involves destructive harvest or non-recurrent measurements. In order to improve our fundamental basis for understanding soil C exchange, a multi-user, open source, searchable database and network of scientists has been formed. The International Soil Carbon Network (ISCN) is a self-chartered, member-based and member-owned network of scientists dedicated to soil carbon science. Attributes of the ISCN include 1) Targeted ISCN Action Groups which represent teams of motivated researchers that propose and pursue specific soil C research questions with the aim of synthesizing seminal articles regarding soil C fate. 2) Datasets to date contributed by institutions and individuals to a comprehensive, searchable open-access database that currently includes over 70,000 geolocated profiles for which soil C and other soil properties. 3) Derivative products resulting from the database, including depth attenuation attributes for C concentration and storage; C storage maps; and model-based assessments of emission/sequestration for future climate scenarios. Several examples illustrate the power of such a database and its engagement with the science community. First, a simplified, data-constrained global ecosystem model estimated a global sensitivity of permafrost soil carbon to climate change (g sensitivity) of -14 to -19 Pg C °C-1 of warming on a 100 years time scale. Second, using mathematical characterizations of depth profiles for organic carbon storage, C at the soil surface reflects Net Primary Production (NPP) and its allotment as moss or litter, while e-folding depths are correlated to rooting depth. Third, storage of deep C is highly

Effects of soil tillage on the microwave emission of soils

NASA Technical Reports Server (NTRS)

Jackson, T. J.; Koopman, G. J.; Oneill, P. E.; Wang, J. R.

1985-01-01

In order to understand the interactions of soil properties and microwave emission better, a series of field experiments were conducted in 1984. Small plots were measured with a truck-mounted passive microwave radiometer operating at 1.4 GHz. These data were collected concurrent with ground observations of soil moisture and bulk density. Treatment effects studied included different soil moisture contents and bulk densities. Evaluations of the data have shown that commonly used models of the dielectric properties of wet soils do not explain the observations obtained in these experiments. This conclusion was based on the fact that the roughness parameters determined through optimization were significantly larger than those observed in similar investigations. These discrepancies are most likely due to the soil structure. Commonly used models assume a homogeneous three phase mixture of soil solids, air and water. Under tilled conditions the soil is actually a two phase mixture of aggregates and voids. Appropriate dielectric models for this tilled condition were evaluated and found to explain the observations. These results indicate that previous conclusions concerning the effects of surface roughness in tilled fields may be incorrect, and they may explain some of the inconsistencies encountered in roughness modeling.

In situ formation of phosphate barriers in soil

DOEpatents

Moore, Robert C.

2002-01-01

Reactive barriers and methods for making reactive barriers in situ in soil for sequestering soil ontaminants including actinides and heavy metals. The barrier includes phosphate, and techniques are disclosed for forming specifically apatite barriers. The method includes injecting dilute reagents into soil in proximity to a contamination plume or source such as a waste drum to achieve complete or partial encapsulation of the waste. Controlled temperature and pH facilitates rapid formation of apatite, for example, where dilute aqueous calcium chloride and dilute aqueous sodium phosphate are the selected reagents. Mixing of reagents to form precipitate is mediated and enhanced through movement of reagents in soil as a result of phenomena including capillary action, movement of groundwater, soil washing and reagent injection pressure.

The interdisciplinary nature of SOIL

NASA Astrophysics Data System (ADS)

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

2015-01-01

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.

Spatial and temporal variability of soil temperature, moisture and surface soil properties

NASA Technical Reports Server (NTRS)

Hajek, B. F.; Dane, J. H.

1993-01-01

The overall objectives of this research were to: (l) Relate in-situ measured soil-water content and temperature profiles to remotely sensed surface soil-water and temperature conditions; to model simultaneous heat and water movement for spatially and temporally changing soil conditions; (2) Determine the spatial and temporal variability of surface soil properties affecting emissivity, reflectance, and material and energy flux across the soil surface. This will include physical, chemical, and mineralogical characteristics of primary soil components and aggregate systems; and (3) Develop surface soil classes of naturally occurring and distributed soil property assemblages and group classes to be tested with respect to water content, emissivity and reflectivity. This document is a report of studies conducted during the period funded by NASA grants. The project was designed to be conducted over a five year period. Since funding was discontinued after three years, some of the research started was not completed. Additional publications are planned whenever funding can be obtained to finalize data analysis for both the arid and humid locations.

An evaluation of different soil washing solutions for remediating arsenic-contaminated soils.

PubMed

Wang, Yiwen; Ma, Fujun; Zhang, Qian; Peng, Changsheng; Wu, Bin; Li, Fasheng; Gu, Qingbao

2017-04-01

Soil washing is a promising way to remediate arsenic-contaminated soils. Most research has mostly focused on seeking efficient extractants for removing arsenic, but not concerned with any changes in soil properties when using this technique. In this study, the removal of arsenic from a heavily contaminated soil employing different washing solutions including H 3 PO 4 , NaOH and dithionite in EDTA was conducted. Subsequently, the changes in soil physicochemical properties and phytotoxicity of each washing technique were evaluated. After washing with 2 M H 3 PO 4 , 2 M NaOH or 0.1 M dithionite in 0.1 M EDTA, the soil samples' arsenic content met the clean-up levels stipulated in China's environmental regulations. H 3 PO 4 washing decreased soil pH, Ca, Mg, Al, Fe, and Mn concentrations but increased TN and TP contents. NaOH washing increased soil pH but decreased soil TOC, TN and TP contents. Dithionite in EDTA washing reduced soil TOC, Ca, Mg, Al, Fe, Mn and TP contents. A drastic color change was observed when the soil sample was washed with H 3 PO 4 or 0.1 M dithionite in 0.1 M EDTA. After adjusting the soil pH to neutral, wheat planted in the soil sample washed by NaOH evidenced the best growth of all three treated soil samples. These results will help with selecting the best washing solution when remediating arsenic-contaminated soils in future engineering applications. Copyright © 2017 Elsevier Ltd. All rights reserved.

THE IMPORTANCE OF ORGANIC MATTER DISTRIBUTION AND EXTRACT SOIL:SOLUTION RATIO ON THE DESORPTION OF HEAVY METALS FROM SOILS

EPA Science Inventory

The lability (mobility and bioavailability) of metals varies significantly with soil properties for similar total soil metal concentrations. We studied desorption of Cu, Ni and Zn, from 15 diverse, unamended soils. These studies included evaluation of the effects of soil:solution...

Dig It! The Secrets of Soil

Science.gov Websites

It! The Secrets of Soil Come and Explore! Discover the amazing world of soils with images and information from the Dig It! The Secrets of Soil exhibit from the Smithsonian's National Museum of Natural and new web content will be added over the coming months including a new soil blog. New Interactives

Soil Functional Mapping: A Geospatial Framework for Scaling Soil Carbon Cycling

NASA Astrophysics Data System (ADS)

Lawrence, C. R.

2017-12-01

Climate change is dramatically altering biogeochemical cycles in most terrestrial ecosystems, particularly the cycles of water and carbon (C). These changes will affect myriad ecosystem processes of importance, including plant productivity, C exports to aquatic systems, and terrestrial C storage. Soil C storage represents a critical feedback to climate change as soils store more C than the atmosphere and aboveground plant biomass combined. While we know plant and soil C cycling are strongly coupled with soil moisture, substantial unknowns remain regarding how these relationships can be scaled up from soil profiles to ecosystems. This greatly limits our ability to build a process-based understanding of the controls on and consequences of climate change at regional scales. In an effort to address this limitation we: (1) describe an approach to classifying soils that is based on underlying differences in soil functional characteristics and (2) examine the utility of this approach as a scaling tool that honors the underlying soil processes. First, geospatial datasets are analyzed in the context of our current understanding of soil C and water cycling in order to predict soil functional units that can be mapped at the scale of ecosystems or watersheds. Next, the integrity of each soil functional unit is evaluated using available soil C data and mapping units are refined as needed. Finally, targeted sampling is conducted to further differentiate functional units or fill in any data gaps that are identified. Completion of this workflow provides new geospatial datasets that are based on specific soil functions, in this case the coupling of soil C and water cycling, and are well suited for integration with regional-scale soil models. Preliminary results from this effort highlight the advantages of a scaling approach that balances theory, measurement, and modeling.

Latent heat sink in soil heat flux measurements

USDA-ARS?s Scientific Manuscript database

The surface energy balance includes a term for soil heat flux. Soil heat flux is difficult to measure because it includes conduction and convection heat transfer processes. Accurate representation of soil heat flux is an important consideration in many modeling and measurement applications. Yet, the...

Soil process-oriented modelling of within-field variability based on high-resolution 3D soil type distribution maps.

NASA Astrophysics Data System (ADS)

Bönecke, Eric; Lück, Erika; Gründling, Ralf; Rühlmann, Jörg; Franko, Uwe

2016-04-01

Today, the knowledge of within-field variability is essential for numerous purposes, including practical issues, such as precision and sustainable soil management. Therefore, process-oriented soil models have been applied for a considerable time to answer question of spatial soil nutrient and water dynamics, although, they can only be as consistent as their variation and resolution of soil input data. Traditional approaches, describe distribution of soil types, soil texture or other soil properties for greater soil units through generalised point information, e.g. from classical soil survey maps. Those simplifications are known to be afflicted with large uncertainties. Varying soil, crop or yield conditions are detected even within such homogenised soil units. However, recent advances of non-invasive soil survey and on-the-go monitoring techniques, made it possible to obtain vertical and horizontal dense information (3D) about various soil properties, particularly soil texture distribution which serves as an essential soil key variable affecting various other soil properties. Thus, in this study we based our simulations on detailed 3D soil type distribution (STD) maps (4x4 m) to adjacently built-up sufficient informative soil profiles including various soil physical and chemical properties. Our estimates of spatial STD are based on high-resolution lateral and vertical changes of electrical resistivity (ER), detected by a relatively new multi-sensor on-the-go ER monitoring device. We performed an algorithm including fuzzy-c-mean (FCM) logic and traditional soil classification to estimate STD from those inverted and layer-wise available ER data. STD is then used as key input parameter for our carbon, nitrogen and water transport model. We identified Pedological horizon depths and inferred hydrological soil variables (field capacity, permanent wilting point) from pedotransferfunctions (PTF) for each horizon. Furthermore, the spatial distribution of soil organic carbon

The influence of soil organic matter chemistry and site/soil properties in predicting the decomposability of tundra soils

NASA Astrophysics Data System (ADS)

Matamala, R.; Jastrow, J. D.; Fan, Z.; Liang, C.; Calderon, F.; Michaelson, G.; Mishra, U.; Ping, C. L.

2017-12-01

With the increase in high latitude warming, there is a need to better understand the potential vulnerability of soil organic matter (SOM) stored in Arctic regions. In this study, we used mid infrared spectroscopy (MidIR) to determine the influence of soil chemistry and site properties in the short-term mineralization potential of SOM stored in tundra soils. Soils from the active and permafrost layers were collected from four tundra sites on the Coastal Plain, and Arctic Foothills of the North Slope of Alaska and were incubated for 60 days at a range of temperatures. Site and soil properties including acidic versus non-acidic tundra, lowland versus upland areas, total soil organic carbon (TOC) and total nitrogen (TN) concentrations, 60-day carbon mineralization potential (CMP), MidIR spectra and the chemical composition of the SOM stored in these soils were determined. Partial least squares (PLS) models for CMP versus MidIR spectra were produced upon splitting the dataset into site and soil properties categories. We found that SOM composition determined by MidIR spectroscopy was most effective in predicting CMP for tundra soils and it was most relevant for the active-layer mineral and upper permafrost soil horizons and/or soils with C concentrations of 10% or lower. Analysis of the factor loadings and standardized beta coefficients from the CMP PLS models indicated that spectral bands associated with clay contents, phenolic OH, aliphatic, silicates, carboxylic acids, and polysaccharides were influential for lower TOC soils, but these bands were less important for higher TOC soils. High TOC soils were influenced by a combination of other factors. Our results suggest that different factors affect the short-term CMP of SOM in tundra soils depending on the amount of TOC present. We show MidIR as a powerful tool for quickly and reasonably estimating the short-term CMP of tundra soils. Widespread application of MidIR measurements to already collected and archived tundra

Soil aggregation and slope stability related to soil density, root length, and mycorrhiza

NASA Astrophysics Data System (ADS)

Graf, Frank; Frei, Martin

2013-04-01

Eco-engineering measures combine the use of living plants and inert mechanical constructions to protect slopes against erosion and shallow mass movement. Whereas in geotechnical engineering several performance standards and guidelines for structural safety and serviceability of construction exist, there is a lack of comparable tools in the field of ecological restoration. Various indicators have been proposed, including the fractal dimension of soil particle size distribution, microbiological parameters, and soil aggregate stability. We present results of an soil aggregate stability investigation and compare them with literature data of the angle of internal friction ?' which is conventionally used in slope stability analysis and soil failure calculation. Aggregate stability tests were performed with samples of differently treated moraine, including soil at low (~15.5 kN/m³) and high (~19.0 kN/m³) dry unit weight, soil planted with Alnus incana (White Alder) as well as the combination of soil planted with alder and inoculated with the mycorrhizal fungus Melanogaster variegatus s.l. After a 20 weeks growth period in a greenhouse, a total of 100 samples was tested and evaluated. Positive correlations were found between the soil aggregate stability and the three variables dry unit weight, root length per soil volume, and degree of mycorrhization. Based on robust statistics it turned out that dry unit weight and mycorrhization degree were strongest correlated with soil aggregate stability. Compared to the non-inoculated control plants, mycorrhized White Alder produced significantly more roots and higher soil aggregate stability. Furthermore, the combined biological effect of plant roots and mycorrhizal mycelia on aggregate stability on soil with low density (~15.5 kN/m³) was comparable to the compaction effect of the pure soil from 15.5 to ~19.0 kN/m³. Literature data on the effect of vegetation on the angle of internal friction ?' of the same moraine showed

Some effects of mirex on two warm-water fishes

USGS Publications Warehouse

Van Valin, Charles C.; Andrews, Austin K.; Eller, Lafayette L.

1968-01-01

The effects of mirex on two species of warm-water fishes were studied in three experiments in which the fish were exposed either by feeding a mirex-treated diet, or by treating the holding ponds with a mirex formulation. Bluegills were used in the feeding experiment, where three different levels of mirex were incorporated into the diet and fed to fish held in plastic pools, and in the first pond-exposure experiment, in which the fish were held in earthen ponds treated once with a mirex-corncob grit formulation. The third experiment used goldfish held in earthen ponds which also were treated once with the mirex-corncob grit formulation. In general, higher rates of exposure produced higher whole-body residues of mirex in the fish, and, except in bluegills from the lower-treatment ponds of the first contact experiment and in control fish, whole-body residues increased throughout the terms of these experiments. Soil, water, and vegetation samples from the two contact experiments, although subject to large differences between individual samples, contained relatively unchanging mirex concentrations, illustrating that this chemical is highly resistant to degradation or removal. No mortality or tissue pathology in the bluegills could be ascribed to mirex exposure, but the gills and kidneys of mirex-exposed goldfish showed reactions beginning with the samples taken 56 days after treatment, and the numbers of these fish surviving until termination of this experiment were inversely related to treatment level. Total serum protein and hematocrit percentages had no apparent relationship to treatment levels, nor was mirex exposure a demonstrable factor in growth rates in the contact experiments. However, growth of the bluegills in the highest treatment groups of the feeding experiment was adversely affected. Invertebrate populations seemed not to be affected by the mirex treatment in either of the earthen pond experiments.

Soil-moisture sensors and irrigation management

USDA-ARS?s Scientific Manuscript database

This agricultural irrigation seminar will cover the major classes of soil-moisture sensors; their advantages and disadvantages; installing and reading soil-moisture sensors; and using their data for irrigation management. The soil water sensor classes include the resistance sensors (gypsum blocks, g...

At the heart of soil health

USDA-ARS?s Scientific Manuscript database

Soil health is receiving resurgent attention with a number of recent national soil health initiatives which are sponsored by cooperators from diverse sectors including agribusiness, commodity groups, governmental organizations, and non-profits. The health of the soil is dependent on its biology. A...

Soil functional types: surveying the biophysical dimensions of soil security

NASA Astrophysics Data System (ADS)

Cécillon, Lauric; Barré, Pierre

2015-04-01

climate) for a particular soil-provided ecosystem service (e.g. climate regulation)". One SFT can thus include several soil types having the same functionality for a particular soil-provided ES. Another consequence is that SFT maps for two different ES may not superimpose over the same area, since some soils may fall in the same SFT for a service and in different SFT for another one. Soil functional types could be assessed and monitored in space and time by a combination of soil functional traits that correspond to inherent and manageable properties of soils. Their metrology would involve either classic (pedological observations) or advanced (molecular ecology, spectrometry, geophysics) tools. SFT could be studied and mapped at all scales, depending on the purpose of the soil security assessment (e.g. global climate modeling, land planning and management, biodiversity conservation). Overall, research is needed to find a pathway from soil pedological maps to SFT maps which would yield important benefits towards the assessment and monitoring of soil security. Indeed, this methodology would allow (i) reducing the spatial uncertainty on the assessment of ES; (ii) identifying and mapping multifunctional soils, which may be the most important soil resource to preserve. References [1] McBratney et al., 2014. Geoderma 213:203-213. [2] Droogers P, Bouma J, 1997. SSSAJ 61:1704-1710.

Soil Quality Indicator: a new concept

NASA Astrophysics Data System (ADS)

Barão, Lúcia; Basch, Gottlieb

2017-04-01

During the last century, cultivated soils have been intensively exploited for food and feed production. This exploitation has compromised the soils' natural functions and many of the soil-mediated ecosystems services, including its production potential for agriculture. Also, soils became increasingly vulnerable and less resilient to a wide range of threats. To overcome this situation, new and better management practices are needed to prevent soil from degradation. However, to adopt the best management practices in a specific location, it is necessary to evaluate the soil quality status first. Different soil quality indicators have been suggested over the last decades in order to evaluate the soil status, and those are often based on the performance of soil chemical, physical and biological properties. However, the direct link between these properties and the associated soil functions or soil vulnerability to threats appears more difficult to be established. This present work is part of the iSQAPER project- Interactive Soil Quality Assessment in Europe and China for Agricultural Productivity and Environmental Resilience, where new soil quality concepts are explored to provide better information regarding the effects of the most promising agricultural management practices on soil quality. We have developed a new conceptual soil quality indicator which determines the soil quality status, regarding its vulnerability towards different threats. First, different indicators were specifically developed for each of the eight threats considered - Erosion, SOM decline, Poor Structure, Poor water holding capacity, Compaction, N-Leaching, Soil-borne pests and diseases and Salinization. As an example for the case of Erosion, the RUSLE equation for the estimate of the soil annual loss was used. Secondly, a reference classification was established for each indicator to integrate all possible results into a Good, Intermediate or Bad classification. Finally, all indicators were

Influence of Disturbance on Soil Respiration in Biologically Crusted Soil during the Dry Season

PubMed Central

Feng, Wei; Zhang, Yu-qing; Wu, Bin; Zha, Tian-shan; Jia, Xin; Qin, Shu-gao; Shao, Chen-xi; Liu, Jia-bin; Lai, Zong-rui; Fa, Ke-yu

2013-01-01

Soil respiration (Rs) is a major pathway for carbon cycling and is a complex process involving abiotic and biotic factors. Biological soil crusts (BSCs) are a key biotic component of desert ecosystems worldwide. In desert ecosystems, soils are protected from surface disturbance by BSCs, but it is unknown whether Rs is affected by disturbance of this crust layer. We measured Rs in three types of disturbed and undisturbed crusted soils (algae, lichen, and moss), as well as bare land from April to August, 2010, in Mu Us desert, northwest China. Rs was similar among undisturbed soils but increased significantly in disturbed moss and algae crusted soils. The variation of Rs in undisturbed and disturbed soil was related to soil bulk density. Disturbance also led to changes in soil organic carbon and fine particles contents, including declines of 60–70% in surface soil C and N, relative to predisturbance values. Once BSCs were disturbed, Q 10 increased. Our findings indicate that a loss of BSCs cover will lead to greater soil C loss through respiration. Given these results, understanding the disturbance sensitivity impact on Rs could be helpful to modify soil management practices which promote carbon sequestration. PMID:24453845

Soil in the City: Sustainably Improving Urban Soils.

PubMed

Kumar, Kuldip; Hundal, Lakhwinder S

2016-01-01

Large tracts of abandoned urban land, resulting from the deindustrialization of metropolitan areas, are generating a renewed interest among city planners and community organizations envisioning the productive use of this land not only to produce fresh food but to effectively manage stormwater and mitigate the impact of urban heat islands. Healthy and productive soils are paramount to meet these objectives. However, these urban lands are often severely degraded due to anthropogenic activities and are generally contaminated with priority pollutants, especially heavy metals and polycyclic aromatic hydrocarbons. Characterizing these degraded and contaminated soils and making them productive again to restore the required ecosystem services was the theme of the "Soil in the City- 2014" conference organized by W-2170 Committee (USDA's Sponsored Multi-State Research Project: Soil-Based Use of Residuals, Wastewater, & Reclaimed Water). This special section of comprises 12 targeted papers authored by conference participants to make available much needed information about the characteristics of urban soils. Innovative ways to mitigate the risks from pollutants and to improve the soil quality using local resources are discussed. Such practices include the use of composts and biosolids to grow healthy foods, reclaim brownfields, manage stormwater, and improve the overall ecosystem functioning of urban soils. These papers provide a needed resource for educating policymakers, practitioners, and the general public about using locally available resources to restore fertility, productivity, and ecosystem functioning of degraded urban land to revitalize metropolitan areas for improving the overall quality of life for a large segment of a rapidly growing urban population. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

Gap assessment in current soil monitoring networks across Europe for measuring soil functions

NASA Astrophysics Data System (ADS)

van Leeuwen, J. P.; Saby, N. P. A.; Jones, A.; Louwagie, G.; Micheli, E.; Rutgers, M.; Schulte, R. P. O.; Spiegel, H.; Toth, G.; Creamer, R. E.

2017-12-01

Soil is the most important natural resource for life on Earth after water. Given its fundamental role in sustaining the human population, both the availability and quality of soil must be managed sustainably and protected. To ensure sustainable management we need to understand the intrinsic functional capacity of different soils across Europe and how it changes over time. Soil monitoring is needed to support evidence-based policies to incentivise sustainable soil management. To this aim, we assessed which soil attributes can be used as potential indicators of five soil functions; (1) primary production, (2) water purification and regulation, (3) carbon sequestration and climate regulation, (4) soil biodiversity and habitat provisioning and (5) recycling of nutrients. We compared this list of attributes to existing national (regional) and EU-wide soil monitoring networks. The overall picture highlighted a clearly unbalanced dataset, in which predominantly chemical soil parameters were included, and soil biological and physical attributes were severely under represented. Methods applied across countries for indicators also varied. At a European scale, the LUCAS-soil survey was evaluated and again confirmed a lack of important soil biological parameters, such as C mineralisation rate, microbial biomass and earthworm community, and soil physical measures such as bulk density. In summary, no current national or European monitoring system exists which has the capacity to quantify the five soil functions and therefore evaluate multi-functional capacity of a soil and in many countries no data exists at all. This paper calls for the addition of soil biological and some physical parameters within the LUCAS-soil survey at European scale and for further development of national soil monitoring schemes.

Survey of methods for soil moisture determination

NASA Technical Reports Server (NTRS)

Schmugge, T. J.; Jackson, T. J.; Mckim, H. L.

1979-01-01

Existing and proposed methods for soil moisture determination are discussed. These include: (1) in situ investigations including gravimetric, nuclear, and electromagnetic techniques; (2) remote sensing approaches that use the reflected solar, thermal infrared, and microwave portions of the electromagnetic spectrum; and (3) soil physics models that track the behavior of water in the soil in response to meteorological inputs (precipitation) and demands (evapotranspiration). The capacities of these approaches to satisfy various user needs for soil moisture information vary from application to application, but a conceptual scheme for merging these approaches into integrated systems to provide soil moisture information is proposed that has the potential for meeting various application requirements.

[Soil hydrolase characteristics in late soil-thawing period in subalpine/alpine forests of west Sichuan].

PubMed

Tan, Bo; Wu, Fu-Zhong; Yang, Wan-Qin; Yu, Sheng; Yang, Yu-Lian; Wang, Ao

2011-05-01

Late soil-thawing period is a critical stage connecting winter and growth season. The significant temperature fluctuation at this stage might have strong effects on soil ecological processes. In order to understand the soil biochemical processes at this stage in the subalpine/alpine forests of west Sichuan, soil samples were collected from the representative forests including primary fir forest, fir and birch mixed forest, and secondary fir forest in March 5-April 25, 2009, with the activities of soil invertase, urease, and phosphatase (neutral, acid and alkaline phosphatases) measured. In soil frozen period, the activities of the three enzymes in test forests still kept relatively higher. With the increase of soil temperature, the activities of hydrolases at the early stage of soil-thawing decreased rapidly after a sharp increase, except for neutral phosphatease. Thereafter, there was an increase in the activities of urease and phosphatase. Relative to soil mineral layer, soil organic layer had higher hydrolase activity in late soil-thawing period, and showed more obvious responses to the variation of soil temperature.

Soil properties, soil functions and soil security

NASA Astrophysics Data System (ADS)

Poggio, Laura; Gimona, Alessandro

2017-04-01

Soil plays a crucial role in the ecosystem functioning such as food production, capture and storage of water, carbon and nutrients and in the realisation of a number of UN Sustainable Developments Goals. In this work we present an approach to spatially and jointly assess the multiple contributions of soil to the delivery of ecosystem services within multiple land-use system. We focussed on the modelling of the impact of soil on sediment retention, carbon storage, storing and filtering of nutrients, habitat for soil organisms and water regulation, taking into account examples of land use and climate scenarios. Simplified models were used for the single components. Spatialised Bayesian Belief networks were used for the jointly assessment and mapping of soil contribution to multiple land use and ecosystem services. We integrated continuous 3D soil information derived from digital soil mapping approaches covering the whole of mainland Scotland, excluding the Northern Islands. Uncertainty was accounted for and propagated across the whole process. The Scottish test case highlights the differences in roles between mineral and organic soils and provides an example of integrated study assessing the contributions of soil. The results show the importance of the multi-functional analysis of the contribution of soils to the ecosystem service delivery and UN SDGs.

The Changing Model of Soil

NASA Astrophysics Data System (ADS)

Richter, D. D.; Yaalon, D.

2012-12-01

The contemporary genetic model of soil is changing rapidly in response to advances in soil science and to human and environmental forcings in the 21st century (Richter and Yaalon, 2012). Three ongoing changes in the model of soil include that: (1) lower soil boundaries are much deeper than the solum, historically the O to B horizons, (2) most soils are polygenetic paleosols, products of soil-forming processes that have ranged widely over soils' lifetimes, and (3) soils are globally human-natural bodies, no longer natural bodies. Together, these changes in the model of soil mean that human forcings are a global wave of soil polygenesis altering fluxes of matter and energy and transforming soil thermodynamics as potentially very deep systems. Because soils are non-linear systems resulting from high-order interactions of physics, chemistry, and biology, trajectories of how human forcings alter soils over decades are not readily predictable and require long-term soil observations. There is much to learn about how soils are changing internally as central components of management systems and externally in relation to wider environments. To be critical, research has been remarkably superficial in studies of soil, reductionist in approach, and lacking in time-series observations of responses to soil management. While this criticism may sound negative, it creates significant opportunities for contemporary soil scientists.

Teaching About the Links Between Soils and Climate: An International Year of Soil Outreach by the Soil Science Society of America

NASA Astrophysics Data System (ADS)

Brevik, Eric C.

2015-04-01

Soil scientists are well aware of the intimate links that exist between soils and climate, but the same is not always true of the broader population. In an attempt to help address this, the Soil Science Society of America (SSSA) has designated the theme "Soils and Climate" for the month of November, 2015 as part of the SSSA International Year of Soil (IYS) celebration. The topic has been further subdivided into three subthemes: 1) carbon sequestration and greenhouse gases, 2) Soils and past environments, and 3) Desertification and drought. Each subtheme outreach has two parts 1) lesson plans that K-12 educators can use in their classrooms, and 2) materials that a trained soil scientist can present to the general public. Activities developed for the theme include classroom activities to accompany an online game that students can play to see how farm management choices influence greenhouse gas emissions, questions to go with a vermicomposting activity, and discussion session questions to go with a movie on the USA Dust Bowl. All materials are available online free of charge. The Soils and Climate materials can be found at https://www.soils.org/iys/12-month-resources/november; all of the SSSA IYS materials can be found at https://www.soils.org/iys.

Effects of soil amendment on soil characteristics and maize yield in Horqin Sandy Land

NASA Astrophysics Data System (ADS)

Zhou, L.; Liu, J. H.; Zhao, B. P.; Xue, A.; Hao, G. C.

2016-08-01

A 4-year experiment was conducted to investigate the inter-annual effects of sandy soil amendment on maize yield, soil water storage and soil enzymatic activities in sandy soil in Northeast China in 2010 to 2014. We applied the sandy soil amendment in different year, and investigated the different effects of sandy soil amendment in 2014. There were six treatments including: (1) no sandy soil amendment application (CK); (2) one year after applying sandy soil amendment (T1); (3) two years after applying sandy soil amendment(T2); (4) three years after applying sandy soil amendment(T3); (5)four years after applying sandy soil amendment(T4); (6) five years after applying sandy soil amendment (T5). T refers to treatment, and the number refers to the year after application of the sandy soil amendment. Comparing with CK, sandy soil amendments improved the soil water storage, soil urease, invertase, and catalase activity in different growth stages and soil layers, the order of soil water storage in all treatments roughly performed: T3 > T5 > T4 > T2 > T1 > CK. the order of soil urease, invertase, and catalase activity in all treatments roughly performed: T5 > T3 > T4 > T2 > T1 > CK. Soil application of sandy soil amendment significantly (p≤⃒0.05) increased the grain yield and biomass yield by 22.75%-41.42% and 29.92%-45.45% respectively, and maize yield gradually increased with the years go by in the following five years. Sandy soil amendment used in poor sandy soil had a positive effect on soil water storage, soil enzymatic activities and maize yield, after five years applied sandy soil amendment (T5) showed the best effects among all the treatments, and deserves further research.

N2O emissions from humid tropical agricultural soils: effects of soil moisture, texture and nitrogen availability

Treesearch

A.M. Weitza; E. Linderb; S. Frolkingc; P.M. Crillc; M. Keller

2001-01-01

We studied soil moisture dynamics and nitrous oxide (N2O) ¯uxes from agricultural soils in the humid tropics of Costa Rica. Using a splitplot design on two soils (clay, loam) we compared two crop types (annual, perennial) each unfertilized and fertilized. Both soils are of andic origin. Their properties include relatively low bulk density and high organic matter...

kNOw Soil - kNOw Life: Integrating soil science across disciplines

NASA Astrophysics Data System (ADS)

Lindbo, D. L.; Kozlowski, D.; Robinson, C.; Chapman, S.

2014-12-01

Teaching primary and secondary school students (K-12) about science and art, although absolutely critical, can be difficult. Teachers have specific standards or subject matters that they are required to cover and often soils and soil science is not included in that list. We have struggled with ways to bring soil science information to the larger audience as the direct approach meets with resistance due to the time commitments to other standards. Our approach now is to use soils as a media or vehicle to teach key concepts in broad subject areas. We have developed several lesson plans in science, geography, math and art that focus on a concept but use soils to convey it. For example students make "mini" monoliths of a state soil. During this exercise students need to use skills in geography to find where their state soil occurs in their state and in the country. They need to understand colors in order to choose the correct colors to use to make their monolith. Finally, they must understand how scales work in order to make the monolith accurate in terms of horizon depths. Throughout the exercise discussion on my certain colors occur in the soil can be discussed. This discussion can lead to a qualitative understanding of chemistry and biology. This presentation will demonstrate this lesson and several others that have been developed and available through the Soil Science Society of America's K12 Education Committee and our International Year of Soil website.

Impact of soil properties on critical concentrations of cadmium, lead, copper, zinc, and mercury in soil and soil solution in view of ecotoxicological effects.

PubMed

de Vries, Wim; Lofts, Steve; Tipping, Ed; Meili, Markus; Groenenberg, Jan E; Schütze, Gudrun

2007-01-01

Risk assessment for metals in terrestrial ecosystems, including assessments of critical loads, requires appropriate critical limits for metal concentrations in soil and soil solution. This chapter presents an overview of methodologies used to derive critical (i) reactive and total metal concentrations in soils and (ii) free metal ion and total metal concentrations in soil solution for Cd, Pb, Cu, Zn, and Hg, taking into account the effect of soil properties related to ecotoxicological effects. Most emphasis is given to the derivation of critical free and total metal concentrations in soil solution, using available NOEC soil data and transfer functions relating solid-phase and dissolved metal concentrations. This approach is based on the assumption that impacts on test organisms (plants, microorganisms, and soil invertebrates) are mainly related to the soil solution concentration (activity) and not to the soil solid-phase content. Critical Cd, Pb, Cu, Zn, and Hg concentrations in soil solution vary with pH and DOC level. The results obtained are generally comparable to those derived for surface waters based on impacts to aquatic organisms. Critical soil metal concentrations, related to the derived soil solution limits, can be described as a function of pH and organic matter and clay content, and varying about one order of magnitude between different soil types.

Adaptive management for soil ecosystem services.

PubMed

Birgé, Hannah E; Bevans, Rebecca A; Allen, Craig R; Angeler, David G; Baer, Sara G; Wall, Diana H

2016-12-01

Ecosystem services provided by soil include regulation of the atmosphere and climate, primary (including agricultural) production, waste processing, decomposition, nutrient conservation, water purification, erosion control, medical resources, pest control, and disease mitigation. The simultaneous production of these multiple services arises from complex interactions among diverse aboveground and belowground communities across multiple scales. When a system is mismanaged, non-linear and persistent losses in ecosystem services can arise. Adaptive management is an approach to management designed to reduce uncertainty as management proceeds. By developing alternative hypotheses, testing these hypotheses and adjusting management in response to outcomes, managers can probe dynamic mechanistic relationships among aboveground and belowground soil system components. In doing so, soil ecosystem services can be preserved and critical ecological thresholds avoided. Here, we present an adaptive management framework designed to reduce uncertainty surrounding the soil system, even when soil ecosystem services production is not the explicit management objective, so that managers can reach their management goals without undermining soil multifunctionality or contributing to an irreversible loss of soil ecosystem services. Copyright © 2016. Published by Elsevier Ltd.

Adaptive management for soil ecosystem services

USGS Publications Warehouse

Birge, Hannah E.; Bevans, Rebecca A.; Allen, Craig R.; Angeler, David G.; Baer, Sara G.; Wall, Diana H.

2016-01-01

Ecosystem services provided by soil include regulation of the atmosphere and climate, primary (including agricultural) production, waste processing, decomposition, nutrient conservation, water purification, erosion control, medical resources, pest control, and disease mitigation. The simultaneous production of these multiple services arises from complex interactions among diverse aboveground and belowground communities across multiple scales. When a system is mismanaged, non-linear and persistent losses in ecosystem services can arise. Adaptive management is an approach to management designed to reduce uncertainty as management proceeds. By developing alternative hypotheses, testing these hypotheses and adjusting management in response to outcomes, managers can probe dynamic mechanistic relationships among aboveground and belowground soil system components. In doing so, soil ecosystem services can be preserved and critical ecological thresholds avoided. Here, we present an adaptive management framework designed to reduce uncertainty surrounding the soil system, even when soil ecosystem services production is not the explicit management objective, so that managers can reach their management goals without undermining soil multifunctionality or contributing to an irreversible loss of soil ecosystem services.

Assessing soil biodiversity potentials in Europe.

PubMed

Aksoy, Ece; Louwagie, Geertrui; Gardi, Ciro; Gregor, Mirko; Schröder, Christoph; Löhnertz, Manuel

2017-07-01

Soil is important as a critical component for the functioning of terrestrial ecosystems. The largest part of the terrestrial biodiversity relies, directly or indirectly, on soil. Furthermore, soil itself is habitat to a great diversity of organisms. The suitability of soil to host such a diversity is strongly related to its physico-chemical features and environmental properties. However, due to the complexity of both soil and biodiversity, it is difficult to identify a clear and unambiguous relationship between environmental parameters and soil biota. Nevertheless, the increasing diffusion of a more integrated view of ecosystems, and in particular the development of the concept of ecosystem services, highlights the need for a better comprehension of the role played by soils in offering these services, including the habitat provision. An assessment of the capability of soils to host biodiversity would contribute to evaluate the quality of soils in order to help policy makers with the development of appropriate and sustainable management actions. However, so far, the heterogeneity of soils has been a barrier to the production of a large-scale framework that directly links soil features to organisms living within it. The current knowledge on the effects of soil physico-chemical properties on biota and the available data at continental scale open the way towards such an evaluation. In this study, the soil habitat potential for biodiversity was assessed and mapped for the first time throughout Europe by combining several soil features (pH, soil texture and soil organic matter) with environmental parameters (potential evapotranspiration, average temperature, soil biomass productivity and land use type). Considering the increasingly recognized importance of soils and their biodiversity in providing ecosystem services, the proposed approach appears to be a promising tool that may contribute to open a forum on the need to include soils in future environmental policy making

Rock Content Influence on Soil Hydraulic Properties

NASA Astrophysics Data System (ADS)

Parajuli, K.; Sadeghi, M.; Jones, S. B.

2015-12-01

Soil hydraulic properties including the soil water retention curve (SWRC) and hydraulic conductivity function are important characteristics of soil affecting a variety of soil properties and processes. The hydraulic properties are commonly measured for seived soils (i.e. particles < 2 mm), but many natural soils include rock fragments of varying size that alter bulk hydraulic properties. Relatively few studies have addressed this important problem using physically-based concepts. Motivated by this knowledge gap, we set out to describe soil hydraulic properties using binary mixtures (i.e. rock fragment inclusions in a soil matrix) based on individual properties of the rock and soil. As a first step of this study, special attention was devoted to the SWRC, where the impact of rock content on the SWRC was quantified using laboratory experiments for six different mixing ratios of soil matrix and rock. The SWRC for each mixture was obtained from water mass and water potential measurements. The resulting data for the studied mixtures yielded a family of SWRC indicating how the SWRC of the mixture is related to that of the individual media, i.e., soil and rock. A consistent model was also developed to describe the hydraulic properties of the mixture as a function of the individual properties of the rock and soil matrix. Key words: Soil hydraulic properties, rock content, binary mixture, experimental data.

[Variations of soil fertility level in red soil region under long-term fertilization].

PubMed

Yu, Han-qing; Xu, Ming-gang; Lü, Jia-long; Bao, Yao-xian; Sun, Nan; Gao, Ju-sheng

2010-07-01

Based on the long-term (1982-2007) field experiment of "anthropogenic mellowing of raw soil" at the Qiyang red soil experimental station under Chinese Academy of Agricultural Sciences, and by using numerical theory, this paper studied the variations of the fertility level of granite red soil, quaternary red soil, and purple sandy shale soil under six fertilization patterns. The fertilization patterns included non-fertilization (CK), straw-returning without fertilizers (CKR), chemical fertilization (NPK), NPK plus straw-return (NPKR), rice straw application (M), and M plus straw-return (MR). The soil integrated fertility index (IFI) was significantly positively correlated with relative crop yield, and could better indicate soil fertility level. The IFI values of the three soils all were in the order of NPK, NPKR > M, MR > CK, CKR, with the highest value in treatment NPKR (0.77, 0.71, and 0.71 for granite red soil, quaternary red soil, and purple sandy shale soil, respectively). Comparing with that in the treatments of no straw-return, the IFI value in the treatments of straw return was increased by 6.72%-18.83%. A turning point of the IFI for all the three soils was observed at about 7 years of anthropogenic mellowing, and the annual increasing rate of the IFI was in the sequence of purple sandy shale soil (0.016 a(-1)) > quaternary red clay soil (0.011 a(-1)) > granite red soil (0.006 a(-1)). It was suggested that a combined application of organic and chemical fertilizers and/or straw return could be an effective and fast measure to enhance the soil fertility level in red soil region.

Measuring Soil Moisture in Skeletal Soils Using a COSMOS Rover

NASA Astrophysics Data System (ADS)

Medina, C.; Neely, H.; Desilets, D.; Mohanty, B.; Moore, G. W.

2017-12-01

The presence of coarse fragments directly influences the volumetric water content of the soil. Current surface soil moisture sensors often do not account for the presence of coarse fragments, and little research has been done to calibrate these sensors under such conditions. The cosmic-ray soil moisture observation system (COSMOS) rover is a passive, non-invasive surface soil moisture sensor with a footprint greater than 100 m. Despite its potential, the COSMOS rover has yet to be validated in skeletal soils. The goal of this study was to validate measurements of surface soil moisture as taken by a COSMOS rover on a Texas skeletal soil. Data was collected for two soils, a Marfla clay loam and Chinati-Boracho-Berrend association, in West Texas. Three levels of data were collected: 1) COSMOS surveys at three different soil moistures, 2) electrical conductivity surveys within those COSMOS surveys, and 3) ground-truth measurements. Surveys with the COSMOS rover covered an 8000-h area and were taken both after large rain events (>2") and a long dry period. Within the COSMOS surveys, the EM38-MK2 was used to estimate the spatial distribution of coarse fragments in the soil around two COSMOS points. Ground truth measurements included coarse fragment mass and volume, bulk density, and water content at 3 locations within each EM38 survey. Ground-truth measurements were weighted using EM38 data, and COSMOS measurements were validated by their distance from the samples. There was a decrease in water content as the percent volume of coarse fragment increased. COSMOS estimations responded to both changes in coarse fragment percent volume and the ground-truth volumetric water content. Further research will focus on creating digital soil maps using landform data and water content estimations from the COSMOS rover.

Soil properties controlling Zn speciation and fractionation in contaminated soils

NASA Astrophysics Data System (ADS)

Jacquat, Olivier; Voegelin, Andreas; Kretzschmar, Ruben

2009-09-01

We determined the speciation of Zn in 49 field soils differing widely in pH (4.1-7.7) and total Zn content (251-30,090 mg/kg) by using extended X-ray absorption fine structure (EXAFS) spectroscopy. All soils had been contaminated since several decades by inputs of aqueous Zn with runoff-water from galvanized power line towers. Pedogenic Zn species identified by EXAFS spectroscopy included Zn in hydroxy-interlayered minerals (Zn-HIM), Zn-rich phyllosilicates, Zn-layered double hydroxide (Zn-LDH), hydrozincite, and octahedrally and tetrahedrally coordinated sorbed or complexed Zn. Zn-HIM was only observed in (mostly acidic) soils containing less than 2000 mg/kg of Zn, reflecting the high affinity but limited sorption capacity of HIM. Zn-bearing precipitates, such as Zn-LDH and Zn-rich trioctahedral phyllosilicates, became more dominant with increasing pH and increasing total Zn content relative to available adsorption sites. Zn-LDH was the most abundant Zn-precipitate and was detected in soils with pH > 5.2. Zn-rich phyllosilicates were detected even at lower soil pH, but were generally less abundant than Zn-LDH. Hydrozincite was only identified in two calcareous soils with extremely high Zn contents. In addition to Zn-LDH, large amounts of Zn in highly contaminated soils were mainly accumulated as sorbed/complexed Zn in tetrahedral coordination. Soils grouped according to their Zn speciation inferred from EXAFS spectroscopy mainly differed with respect to soil pH and total Zn content. Clear differences were observed with respect to Zn fractionation by sequential extraction: From Zn-HIM containing soils, most of the total Zn was recovered in the exchangeable and the most recalcitrant fractions. In contrast, from soils containing the highest percentage of Zn-precipitates, Zn was mainly extracted in intermediate extraction steps. The results of this study demonstrate that soil pH and Zn contamination level relative to available adsorption sites are the most important

Soil fertility and plant diversity enhance microbial performance in metal-polluted soils.

PubMed

Stefanowicz, Anna M; Kapusta, Paweł; Szarek-Łukaszewska, Grażyna; Grodzińska, Krystyna; Niklińska, Maria; Vogt, Rolf D

2012-11-15

This study examined the effects of soil physicochemical properties (including heavy metal pollution) and vegetation parameters on soil basal respiration, microbial biomass, and the activity and functional richness of culturable soil bacteria and fungi. In a zinc and lead mining area (S Poland), 49 sites were selected to represent all common plant communities and comprise the area's diverse soil types. Numerous variables describing habitat properties were reduced by PCA to 7 independent factors, mainly representing subsoil type (metal-rich mining waste vs. sand), soil fertility (exchangeable Ca, Mg and K, total C and N, organic C), plant species richness, phosphorus content, water-soluble heavy metals (Zn, Cd and Pb), clay content and plant functional diversity (based on graminoids, legumes and non-leguminous forbs). Multiple regression analysis including these factors explained much of the variation in most microbial parameters; in the case of microbial respiration and biomass, it was 86% and 71%, respectively. The activity of soil microbes was positively affected mainly by soil fertility and, apparently, by the presence of mining waste in the subsoil. The mining waste contained vast amounts of trace metals (total Zn, Cd and Pb), but it promoted microbial performance due to its inherently high content of macronutrients (total Ca, Mg, K and C). Plant species richness had a relatively strong positive effect on all microbial parameters, except for the fungal component. In contrast, plant functional diversity was practically negligible in its effect on microbes. Other explanatory variables had only a minor positive effect (clay content) or no significant influence (phosphorus content) on microbial communities. The main conclusion from this study is that high nutrient availability and plant species richness positively affected the soil microbes and that this apparently counteracted the toxic effects of metal contamination. Copyright © 2012 Elsevier B.V. All rights

Effect of soil texture on phytoremediation of arsenic-contaminated soils

NASA Astrophysics Data System (ADS)

Pallud, C. E.; Matzen, S. L.; Olson, A.

2015-12-01

Soil arsenic (As) contamination is a global problem, resulting in part from anthropogenic activities, including the use of arsenical pesticides and treated wood, mining, and irrigated agriculture. Phytoextraction using the hyperaccumulating fern Pteris vittata is a promising new technology to remediate soils with shallow arsenic contamination with minimal site disturbance. However, many challenges still lie ahead for a global application of phytoremediation. For example, remediation times using P. vittata are on the order of decades. In addition, most research on As phytoextraction with P. vittata has examined As removal from sandy soils, where As is more available, with little research focusing on As removal from clayey soils, where As is less available. The objective of this study is to determine the effects of soil texture and soil fertilization on As extraction by P. vittata, to optimize remediation efficiency and decrease remediation time under complex field conditions. A field study was established 2.5 years ago in an abandoned railroad grade contaminated with As (average 85.5 mg kg-1) with texture varying from sandy loam to silty clay loam. Organic N, inorganic N, organic P, inorganic P, and compost were applied to separate sub-plots; control ferns were grown in untreated soil. In a parallel greenhouse experiment, ferns were grown in sandy loam soil extracted from the field (180 mg As kg-1), with similar treatments as those used at the field site, plus a high phosphate treatment and treatments with arbuscular mycorrhizal fungi. In the field study, fern mortality was 24% higher in clayey soil than in sandy soil due to waterlogging, while As was primarily associated with sandy soil. Results from the sandy loam soil indicate that soil treatments did not significantly increase As phytoextraction, which was lower in phosphate-treated ferns than in control ferns, both in the field and greenhouse study. Under greenhouse conditions, ferns treated with organic N were

Soil phosphorus - new insights into a critical cycle across many soil functions

NASA Astrophysics Data System (ADS)

Leinweber, Peter; Zimmer, Dana

2017-04-01

The fate of phosphorus (P-) compounds in the soil - plant - water - system is linked with most soil functions such as productivity for agricultural crops, reactor for nutrient cycling, filter and buffer for water, and biodiversity. The P-compounds, mostly phosphates in a multitude of chemical bonds, may have contradicting influences on soil functions. For instance, P-concentrations may be suboptimal for crop yields but at the same time exceeding the soil filter/buffer capacity for water resources. Modern agriculture has increased this misbalance. Therefore, a better soil P management that balances all soil functions requires a deeper understanding of the P-cycling in the environment. The collaborative project "InnoSoilPhos" in the frame of the BonaRes-program of the German Federal Ministry of Education and Research (BMBF) aims at disclosing the chemical composition, biogeochemical transformations and microbiological fundamentals of P-cycling and P-transport processes across all relevant scales from atomic to catchment and landscapes. The contribution will give an overview on the project and some examples for the latest findings on P-reactions at mineral surfaces (experimental and theoretical), microorganism diversity involved in soil P-transformations, crop yield responses to P-fertilizer regimes (including new P-recycling products) and, finally, hot spots and hot moments of P-release from soils into adjoining freshwater systems. These findings allow some preliminary demands and frame conditions for an improved soil P management to better balance the soil functions and safe the global mineable P resources.

Cultural Patterns of Soil Understanding

NASA Astrophysics Data System (ADS)

Patzel, Nikola; Feller, Christian

2017-04-01

Living soil supports all terrestrial ecosystems. The only global threat to earth's soils comes from human societies' land use and resource consuming activities. Soil perception and understanding by soil scientists are mainly drawn from biophysical parameters and found within Cartesian rationality, and not, or much less consciously from its rather intangible cultural dimension. But nevertheless, human soil perception, soil awareness, and soil relation are a cultural phenomenon, too. Aiming at soil awareness and education, it is of first order importance for the soil science community and the IUSS to study, discuss and communicate also about the cultural perceptions and representations of soil. For any society, cultural patterns in their relation to soil encompass: (i) General culturally underlying structures like (religious or 'secular') myths and belief systems. (ii) The personal, individual relation to/with and behaviour towards soil. This includes implicit concepts of soil being part integral concepts of landscape because the large majority of humans don't see soil as a distinct object. This communication would be to make evident: (i) the importance of cultural patterns and psychic/psychological background concerning soil, by case studies and overviews on different cultural areas, (ii) the necessity to develop reflections on this topic as well to communicate about soil with large public, as to raise awareness soil scientists to the cultural dimension of soils. A working group was recently founded at IUSS (Division 4) on this topic.

Soil properties influence kinetics of soil acid phosphatase in response to arsenic toxicity.

PubMed

Wang, Ziquan; Tan, Xiangping; Lu, Guannan; Liu, Yanju; Naidu, Ravi; He, Wenxiang

2018-01-01

Soil phosphatase, which plays an important role in phosphorus cycling, is strongly inhibited by Arsenic (As). However, the inhibition mechanism in kinetics is not adequately investigated. In this study, we investigated the kinetic characteristics of soil acid phosphatase (ACP) in 14 soils with varied properties, and also explored how kinetic properties of soil ACP changed with different spiked As concentrations. The results showed that the Michaelis constant (K m ) and maximum reaction velocity (V max ) values of soil ACP ranged from 1.18 to 3.77mM and 0.025-0.133mMh -1 in uncontaminated soils. The kinetic parameters of soil ACP in different soils changed differently with As contamination. The K m remained unchanged and V max decreased with increase of As concentration in most acid and neutral soils, indicating a noncompetitive inhibition mechanism. However, in alkaline soils, the K m increased linearly and V max decreased with increase of As concentration, indicating a mixed inhibition mechanism that include competitive and noncompetitive. The competitive inhibition constant (K ic ) and noncompetitive inhibition constant (K iu ) varied among soils and ranged from 0.38 to 3.65mM and 0.84-7.43mM respectively. The inhibitory effect of As on soil ACP was mostly affected by soil organic matter and cation exchange capacity. Those factors influenced the combination of As with enzyme, which resulted in a difference of As toxicity to soil ACP. Catalytic efficiency (V max /K m ) of soil ACP was a sensitive kinetic parameter to assess the ecological risks of soil As contamination. Copyright © 2017 Elsevier Inc. All rights reserved.

Including spatial data in nutrient balance modelling on dairy farms

NASA Astrophysics Data System (ADS)

van Leeuwen, Maricke; van Middelaar, Corina; Stoof, Cathelijne; Oenema, Jouke; Stoorvogel, Jetse; de Boer, Imke

2017-04-01

The Annual Nutrient Cycle Assessment (ANCA) calculates the nitrogen (N) and phosphorus (P) balance at a dairy farm, while taking into account the subsequent nutrient cycles of the herd, manure, soil and crop components. Since January 2016, Dutch dairy farmers are required to use ANCA in order to increase understanding of nutrient flows and to minimize nutrient losses to the environment. A nutrient balance calculates the difference between nutrient inputs and outputs. Nutrients enter the farm via purchased feed, fertilizers, deposition and fixation by legumes (nitrogen), and leave the farm via milk, livestock, manure, and roughages. A positive balance indicates to which extent N and/or P are lost to the environment via gaseous emissions (N), leaching, run-off and accumulation in soil. A negative balance indicates that N and/or P are depleted from soil. ANCA was designed to calculate average nutrient flows on farm level (for the herd, manure, soil and crop components). ANCA was not designed to perform calculations of nutrient flows at the field level, as it uses averaged nutrient inputs and outputs across all fields, and it does not include field specific soil characteristics. Land management decisions, however, such as the level of N and P application, are typically taken at the field level given the specific crop and soil characteristics. Therefore the information that ANCA provides is likely not sufficient to support farmers' decisions on land management to minimize nutrient losses to the environment. This is particularly a problem when land management and soils vary between fields. For an accurate estimate of nutrient flows in a given farming system that can be used to optimize land management, the spatial scale of nutrient inputs and outputs (and thus the effect of land management and soil variation) could be essential. Our aim was to determine the effect of the spatial scale of nutrient inputs and outputs on modelled nutrient flows and nutrient use efficiencies

Soil Health Educational Resources

ERIC Educational Resources Information Center

Hoorman, James J.

2015-01-01

Soil health and cover crops are topics of interest to farmers, gardeners, and students. Three soil health and cover crop demonstrations provide educational resources. Demonstrations one outlines two educational cover crop seed displays, including the advantages and disadvantages. Demonstration two shows how to construct and grow a cover crop root…

Acclimation and soil moisture constrain sugar maple root respiration in experimentally warmed soil.

PubMed

Jarvi, Mickey P; Burton, Andrew J

2013-09-01

The response of root respiration to warmer soil can affect ecosystem carbon (C) allocation and the strength of positive feedbacks between climatic warming and soil CO2 efflux. This study sought to determine whether fine-root (<1 mm) respiration in a sugar maple (Acer saccharum Marsh.)-dominated northern hardwood forest would adjust to experimentally warmed soil, reducing C return to the atmosphere at the ecosystem scale to levels lower than that would be expected using an exponential temperature response function. Infrared heating lamps were used to warm the soil (+4 to +5 °C) in a mature sugar maple forest in a fully factorial design, including water additions used to offset the effects of warming-induced dry soil. Fine-root-specific respiration rates, root biomass, root nitrogen (N) concentration, soil temperature and soil moisture were measured from 2009 to 2011, with experimental treatments conducted from late 2010 to 2011. Partial acclimation of fine-root respiration to soil warming occurred, with soil moisture deficit further constraining specific respiration rates in heated plots. Fine-root biomass and N concentration remained unchanged. Over the 2011 growing season, ecosystem root respiration was not significantly greater in warmed soil. This result would not be predicted by models that allow respiration to increase exponentially with temperature and do not directly reduce root respiration in drier soil.

The Glinka Memorial Soil Monolith Collection: a treasure of Soil Science

NASA Astrophysics Data System (ADS)

Muggler, C. C.; Spaargaren, O.; Hartemink, A. E.

2012-04-01

The first World Congress of Soil Science, held in 1927 in Washington DC, USA, had as one of its highlights the exposition of soils from all over the world. The Russian delegation had planned the presentation of 50 soil monoliths. The soil profiles were collected under the supervision of Konstantin D. Glinka, then director of the Leningrad Agricultural Institute. The soil profiles included a geographical sequence form St Petersburg to the Caucasus and soils from Georgia, Azerbaijan, Kazakhstan, the Amu Darya region and the Siberian Far East. Due to shipping problems they did not arrive on time for the congress, and ended up in an USDA storage facility, where they remained untouched in their original wooden boxes. At first congress Glinka gave a lecture on Dokuchaev's ideas and the Russian developments on soil science, and joined the transcontinental field trip of 30 days that followed the congress. At that congress, Glinka was elected president of the International Soil Science Society, and was in charge to organize the next congress in Russia. However, he passed away a few months after the congress. In the 1970s, after a consultation with Wim Sombroek, then director of the International Soil Museum (ISM) in the Netherlands, the collection was donated to ISRIC by the US Soil Conservation Service. The soil profiles were shipped over in 1980 to become part of the collection of the Museum. The collection was named as "Glinka Memorial Collection" in agreement with the Dokuchaev Soil Institute, Moscow and the U.S. Soil Conservation Service, Washington. The monoliths were treated with a sugar solution by the Russians before shipment to the USA, this way keeping a good preservation quality. They were aimed for a single exhibition and for that they were poorly documented and lacked additional samples. In the early 1990s a project for revisit the sites was set up and six sites around St Petersburg were sampled for a comparative study of the soils within a time span of 70

Relating soil biochemistry to sustainable crop production

USDA-ARS?s Scientific Manuscript database

Amino acids, amino sugars, carbohydrates, phenols, and fatty acids together comprise appreciable proportions of soil organic matter (SOM). Their cycling contribute to soil processes, including nitrogen availability, carbon sequestration and aggregation. For example, soil accumulation of phenols has ...

A long-term soil structure observatory for post-compaction soil structure evolution: design and initial soil structure recovery observations

NASA Astrophysics Data System (ADS)

Keller, Thomas; Colombi, Tino; Ruiz, Siul; Grahm, Lina; Reiser, René; Rek, Jan; Oberholzer, Hans-Rudolf; Schymanski, Stanislaus; Walter, Achim; Or, Dani

2016-04-01

Soil compaction due to agricultural vehicular traffic alters the geometrical arrangement of soil constituents, thereby modifying mechanical properties and pore spaces that affect a range of soil hydro-ecological functions. The ecological and economic costs of soil compaction are dependent on the immediate impact on soil functions during the compaction event, and a function of the recovery time. In contrast to a wealth of soil compaction information, mechanisms and rates of soil structure recovery remain largely unknown. A long-term (>10-yr) soil structure observatory (SSO) was established in 2014 on a loamy soil in Zurich, Switzerland, to quantify rates and mechanisms of structure recovery of compacted arable soil under different post-compaction management treatments. We implemented three initial compaction treatments (using a two-axle agricultural vehicle with 8 Mg wheel load): compaction of the entire plot area (i.e. track-by-track), compaction in wheel tracks, and no compaction. After compaction, we implemented four post-compaction soil management systems: bare soil (BS), permanent grass (PG), crop rotation without mechanical loosening (NT), and crop rotation under conventional tillage (CT). BS and PG provide insights into uninterrupted natural processes of soil structure regeneration under reduced (BS) and normal biological activity (PG). The two cropping systems (NT and CT) enable insights into soil structure recovery under common agricultural practices with minimal (NT) and conventional mechanical soil disturbance (CT). Observations include periodic sampling and measurements of soil physical properties, earthworm abundance, crop measures, electrical resistivity and ground penetrating radar imaging, and continuous monitoring of state variables - soil moisture, temperature, CO2 and O2 concentrations, redox potential and oxygen diffusion rates - for which a network of sensors was installed at various depths (0-1 m). Initial compaction increased soil bulk density

Soil-plant transfer models for metals to improve soil screening value guidelines valid for São Paulo, Brazil.

PubMed

Dos Santos-Araujo, Sabrina N; Swartjes, Frank A; Versluijs, Kees W; Moreno, Fabio Netto; Alleoni, Luís R F

2017-11-07

In Brazil, there is a lack of combined soil-plant data attempting to explain the influence of specific climate, soil conditions, and crop management on heavy metal uptake and accumulation by plants. As a consequence, soil-plant relationships to be used in risk assessments or for derivation of soil screening values are not available. Our objective in this study was to develop empirical soil-plant models for Cd, Cu, Pb, Ni, and Zn, in order to derive appropriate soil screening values representative of humid tropical regions such as the state of São Paulo (SP), Brazil. Soil and plant samples from 25 vegetable species in the production areas of SP were collected. The concentrations of metals found in these soil samples were relatively low. Therefore, data from temperate regions were included in our study. The soil-plant relations derived had a good performance for SP conditions for 8 out of 10 combinations of metal and vegetable species. The bioconcentration factor (BCF) values for Cd, Cu, Ni, Pb, and Zn in lettuce and for Cd, Cu, Pb, and Zn in carrot were determined under three exposure scenarios at pH 5 and 6. The application of soil-plant models and the BCFs proposed in this study can be an important tool to derive national soil quality criteria. However, this methodological approach includes data assessed under different climatic conditions and soil types and need to be carefully considered.

Effect of long-term farming strategies on soil microbiota and soil health

NASA Astrophysics Data System (ADS)

Sommermann, Loreen; Babin, Doreen; Sandmann, Martin; Smalla, Kornelia; Schellenberg, Ingo; Grosch, Rita; Geistlinger, Joerg

2017-04-01

Increasing food and energy demands have resulted in considerable intensification of farming practices, which brought about severe consequences for agricultural soils, e.g. loss of fertility, erosion and enrichment of soil-borne plant diseases. In order to maintain soil quality and health for the future, the development of more extensive and sustainable farming strategies is urgently needed. The soil microbiome is regarded as a key player in soil ecosystem functions, particularly the natural ability of soils to suppress plant pathogens (suppressiveness). Recent studies showed that soil microbial communities are influenced by agricultural management. To further analyze the effects of farming strategies on soil suppressiveness and plant performance, agricultural soils from three long-term field trials in Thyrow, Bernburg (both in Germany) and Therwil (Switzerland) were sampled and subjected to molecular profiling of soil bacteria and fungi using marker genes and high-throughput amplicon sequencing. Significant effects on bacterial as well as fungal community composition, including plant pathogenic and beneficial taxa, were observed among variants of tillage and crop rotation. The least effect on both communities had fertilization, with no significance between variants. Subsequently, the same soils were subjected to growth chamber pot experiments with lettuce as a model (Lactuca sativa). After a growth period of six weeks significant differences in lettuce shoot and soil microbial biomass were observed among soil samples of the different long-term trials. Furthermore, the lettuce rhizosphere exhibited diverse bacterial community compositions as observed by DGGE (denaturing gradient gel electrophoresis). Using group-specific PCR-DGGE fingerprints, bacterial responders to fertilization, soil management and crop rotation were identified among different taxonomic groups. Currently, bacterial and fungal amplicon sequencing of rhizosphere and bulk soil from these pot

Detection of Soil Nitrogen Using Near Infrared Sensors Based on Soil Pretreatment and Algorithms

PubMed Central

Nie, Pengcheng; Dong, Tao; He, Yong; Qu, Fangfang

2017-01-01

Soil nitrogen content is one of the important growth nutrient parameters of crops. It is a prerequisite for scientific fertilization to accurately grasp soil nutrient information in precision agriculture. The information about nutrients such as nitrogen in the soil can be obtained quickly by using a near-infrared sensor. The data can be analyzed in the detection process, which is nondestructive and non-polluting. In order to investigate the effect of soil pretreatment on nitrogen content by near infrared sensor, 16 nitrogen concentrations were mixed with soil and the soil samples were divided into three groups with different pretreatment. The first group of soil samples with strict pretreatment were dried, ground, sieved and pressed. The second group of soil samples were dried and ground. The third group of soil samples were simply dried. Three linear different modeling methods are used to analyze the spectrum, including partial least squares (PLS), uninformative variable elimination (UVE), competitive adaptive reweighted algorithm (CARS). The model of nonlinear partial least squares which supports vector machine (LS-SVM) is also used to analyze the soil reflectance spectrum. The results show that the soil samples with strict pretreatment have the best accuracy in predicting nitrogen content by near-infrared sensor, and the pretreatment method is suitable for practical application. PMID:28492480

Biotoxicity of Mars Analog Soils: Microbial, Dispersal into Desiccated Soils Versus Emplacement in Salt or Ice Inclusions Fluids

NASA Technical Reports Server (NTRS)

Schuerger, A. C.; Ming, Doutlas W.; Golden, D. C.

2010-01-01

Recent evidence from the Opportunity and Spirit rovers and the Mars Express mission suggests that the soils on Mars might be very high in biotoxic materials including sulfate salts, chlorides, and acidifying agents. Yet, very little is known about how the chemistries of Mars soils might affect the survival and growth of terrestrial microorganisms. The primary objectives of the research included: (1) prepare and characterize Mars analog soils amended with potential biotoxic levels of sulfates, chlorides, and acidifying minerals; and (2) use the simulants to conduct a series of toxicology assays to determine if terrestrial microorganisms from spacecraft can survive direct exposure to the biotoxic soils.

Soil bacterial community composition altered by increased nutrient availability in Arctic tundra soils

PubMed Central

Koyama, Akihiro; Wallenstein, Matthew D.; Simpson, Rodney T.; Moore, John C.

2014-01-01

The pool of soil organic carbon (SOC) in the Arctic is disproportionally large compared to those in other biomes. This large quantity of SOC accumulated over millennia due to slow rates of decomposition relative to net primary productivity. Decomposition is constrained by low temperatures and nutrient concentrations, which limit soil microbial activity. We investigated how nutrients limit bacterial and fungal biomass and community composition in organic and mineral soils within moist acidic tussock tundra ecosystems. We sampled two experimental arrays of moist acidic tussock tundra that included fertilized and non-fertilized control plots. One array included plots that had been fertilized annually since 1989 and the other since 2006. Fertilization significantly altered overall bacterial community composition and reduced evenness, to a greater degree in organic than mineral soils, and in the 1989 compared to the 2006 site. The relative abundance of copiotrophic α-Proteobacteria and β-Proteobacteria was higher in fertilized than control soils, and oligotrophic Acidobacteria were less abundant in fertilized than control soils at the 1989 site. Fungal community composition was less sensitive to increased nutrient availability, and fungal responses to fertilization were not consistent between soil horizons and sites. We detected two ectomycorrhizal genera, Russula and Cortinarius spp., associated with shrubs. Their relative abundance was not affected by fertilization despite increased dominance of their host plants in the fertilized plots. Our results indicate that fertilization, which has been commonly used to simulate warming in Arctic tundra, has limited applicability for investigating fungal dynamics under warming. PMID:25324836

Using synthetic polymers to reduce soil erosion after forest fires in Mediterranean soils

NASA Astrophysics Data System (ADS)

Lado, Marcos; Ben-Hur, Meni; Inbar, Assaf

2010-05-01

Forest fires are a major environmental problem in the Mediterranean region because they result in a loss of vegetation cover, changes in biodiversity, increases in greenhouse gasses emission and a potential increase of runoff and soil erosion. The large increases in runoff and sediment yields after high severity fires have been attributed to several factors, among them: increase in soil water repellency; soil sealing by detached particles and by ash particles, and the loss of a surface cover. The presence of a surface cover increases infiltration, and decreases runoff and erosion by several mechanisms which include: rainfall interception, plant evapotranspiration, preservation of soil structure by increasing soil organic matter, and increasing surface roughness. The loss of vegetation cover as a result of fire leaves the surface of the soil exposed to the direct impact of the raindrops, and therefore the sensitivity of the soil to runoff generation and soil loss increases. In this work, we propose a new method to protect soils against post-fire erosion based on the application of synthetic polymers to the soil. Laboratory rainfall simulations and field runoff plots were used to analyze the suitability of the application of synthetic polymers to reduce soil erosion and stabilize soil structure in Mediterranean soils. The combination of these two processes will potentially favor a faster recovery of the vegetation structure. This method has been successfully applied in arable land, however it has not been tested in burnt forests. The outcome of this study may provide important managerial tools for forest management following fires.

Pore-Scale Effects of Soil Structure And Microbial EPS Production On Soil Water Retention

NASA Astrophysics Data System (ADS)

Orner, E.; Anderson, E.; Rubinstein, R. L.; Chau, J. F.; Shor, L. M.; Gage, D. J.

2013-12-01

Climate-induced changes to the hydrological cycle will increase the frequency of extreme weather events including powerful storms and prolonged droughts. Moving forward, one of the major factors limiting primary productivity in terrestrial ecosystems will be sub-optimal soil moisture. We focus here on the ability of soils to retain moisture under drying conditions. A soil's ability to retain moisture is influenced by many factors including its texture, its structure, and the activities of soil microbes. In soil microcosms, the addition of small amounts of microbially-produced extracellular polymeric substances (EPS) can dramatically shift moisture retention curves. The objective of this research is to better understand how soil structure and EPS may act together to retain moisture in unsaturated soils. Replicate micromodels with exactly-conserved 2-D physical geometry were initially filled with aqueous suspensions of one of two types of bacteria: one mutant was ultra- muccoid and the other was non-muccoid. Replicate micromodels were held at a fixed, external, relative humidity, and the position of the air-water interface was imaged over time as water evaporates. There was no forced convection of air or water inside the micromodels: drying was achieved by water evaporation and diffusion alone. We used a fully automated, inverted microscope to image replicate drying lanes each with dimensions of 1 mm x 10 mm. A complete set of images was collected every 30 minutes for 30 hours. The results show devices loaded with the highly muccoid strain remained >40% hydrated for 13 h, while devices loaded with the non-muccoid remained >40% hydrated for only 6 h, and were completely dry by 13 h. Current work is comparing interfacial water fluxes in structured and unstructured settings, and is attempting to model the synergistic effects of soil structure and EPS content on moisture retention in real soils. This research may allow more accurate description of naturally

In situ denitrification and DNRA rates in soils and underlying groundwater of an integrated constructed wetland

NASA Astrophysics Data System (ADS)

Mofizur Rahman Jahangir, Mohammad; Fenton, Owen; McAleer, Eoin; Carroll, Paul; Harrington, Rory; Johnston, Paul; Müller, Christoph; Richards, Karl

2015-04-01

Nitrogen (N) removal efficiency in constructed wetlands (CW) is low and again it does not in itself explain whether the removed N species are reactive or benign. Evaluation of environmental benefits of CW necessitates knowing N removal mechanisms and the fate of the removed N in such system. In situ denitrification and DNRA (dissimilatory nitrate reduction to ammonium) rates were measured in an earthen lined 5-cell integrated CW using 15N-enriched nitrate (NO3--N) push-pull method. Measurements were conducted in 2 groundwater depths (shallow- soils in CW bed; and deep- 4 m below CW soils) in 2 contrasting cells (high vs. low nutrient loads) of the CW. Denitrification (N¬2O-N + N2-N) and DNRA were the major NO3--N removal processes accounting together for 54-79% of the total biochemical removal of the applied NO3--N. Of which 14-17 and 40-68% were removed by denitrification and DNRA, respectively. Both the processes significantly differed with CW cells indicating that N transformations depend on the rate of nutrient loads in different cells. They were significantly higher in shallow than deep groundwater. Environmental conditions were favourable for both the processes (i.e. low dissolved oxygen and low redox potential, high dissolved organic carbon, high total carbon and high dissolved organic N) but DNRA rate was favoured over denitrification by high ambient NH4+ concentrations, reduced sulphide and low pH (5.9 - 7.0). Low pH might have limited denitrification to some extent to an incomplete state, being evident by a high N2O-N/(N2O-N+N2-N) ratio (0.35 ± 0.17, SE). Relatively higher N2O-N/(N2O-N+N2-N) ratio and higher DNRA rate over denitrification suggest that the end products of N transformations are reactive. This N2O can be consumed to N2 and/or emit to atmosphere directly and indirectly. The DNRA rate and accumulation of NH4+ indicated that CW is a net source of NH4+ in groundwater. Ammonium produced by DNRA can be fixed in soils and, when exchange sites are

Evaluation of various combinations of alternative protein feedstuffs to replace soybean meal in diets for pond-raised channel catfish

USDA-ARS?s Scientific Manuscript database

A study was conducted in earthen ponds to evaluate the use of combinations of two or three alternative protein sources to replace soybean meal in diets for Channel Catfish Ictalurus punctatus. Six 28% protein diets containing various combinations of alternative protein feedstuffs including cottonse...

Worldwide organic soil carbon and nitrogen data

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zinke, P.J.; Stangenberger, A.G.; Post, W.M.

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.

Chapter 3: Soil Chemistry

Treesearch

Jennifer D. Knoepp; Leonard F. DeBano; Daniel G. Neary

2005-01-01

The chemical properties of the soil that are affected by fire include individual chemical characteristics, chemical reactions, and chemical processes (DeBano and others 1998). The soil chemical characteristics most commonly affected by fire are organic matter, carbon (C), nitrogen (N), phosphorus (P), sulfur (S), cations, cation exchange capacity, pH, and buffer power...

Intrinsic and induced isoproturon catabolic activity in dissimilar soils and soils under dissimilar land use.

PubMed

Reid, Brian J; Papanikolaou, Niki D; Wilcox, Ronah K

2005-02-01

The catabolic activity with respect to the systemic herbicide isoproturon was determined in soil samples by (14)C-radiorespirometry. The first experiment assessed levels of intrinsic catabolic activity in soil samples that represented three dissimilar soil series under arable cultivation. Results showed average extents of isoproturon mineralisation (after 240 h assay time) in the three soil series to be low. A second experiment assessed the impact of addition of isoproturon (0.05 microg kg(-1)) into these soils on the levels of catabolic activity following 28 days of incubation. Increased catabolic activity was observed in all three soils. A third experiment assessed levels of intrinsic catabolic activity in soil samples representing a single soil series managed under either conventional agricultural practice (including the use of isoproturon) or organic farming practice (with no use of isoproturon). Results showed higher (and more consistent) levels of isoproturon mineralisation in the soil samples collected from conventional land use. The final experiment assessed the impact of isoproturon addition on the levels of inducible catabolic activity in these soils. The results showed no significant difference in the case of the conventional farm soil samples while the induction of catabolic activity in the organic farm soil samples was significant.

Soil health paradigms and implications for disease management.

PubMed

Larkin, Robert P

2015-01-01

Soil health has been defined as the capacity of soil to function as a vital living system to sustain biological productivity, maintain environmental quality, and promote plant, animal, and human health. Building and maintaining soil health are essential to agricultural sustainability and ecosystem function. Management practices that promote soil health, including the use of crop rotations, cover crops and green manures, organic amendments, and conservation tillage, also have generally positive effects on the management of soilborne diseases through a number of potential mechanisms, including increasing soil microbial biomass, activity, and diversity, resulting in greater biological suppression of pathogens and diseases. However, there also may be particular disease issues associated with some soil health management practices. In this review, research and progress made over the past twenty years regarding soil health, sustainability, and soil health management practices, with an emphasis on their implications for and effects on plant disease and disease management strategies, are summarized.

Soil biodiversity and human health

NASA Astrophysics Data System (ADS)

Six, Johan; Pereg, Lily; Brevik, Eric

2017-04-01

Biodiversity is important for the maintenance of soil quality. Healthy, biodiverse soils are crucial for human health and wellbeing from several reasons, for example: biodiversity has been shown to be important in controlling populations of pathogens; healthy, well-covered soils can reduce disease outbreaks; carbon-rich soils may also reduce outbreaks of human and animal parasites; exposure to soil microbes can reduce allergies; soils have provided many of our current antibiotics; soil organisms can provide biological disease and pest control agents, healthy soils mean healthier and more abundant foods; soil microbes can enhance crop plant resilience; healthy soils promote good clean air quality, less prone to wind and water erosion; and healthy soils provide clean and safe water through filtration, decontamination by microbes and removal of pollutants. Soil microbes and other biota provide many benefits to human health. Soil microbes are a source of medicines, such as antibiotics, anticancer drugs and many more. Organisms that affect soil health and thus human health include those involved in nutrient cycling, decomposition of organic matter and determining soil structure (e.g. aggregation). Again these are related to food security but also affect human health in other ways. Many beneficial organisms have been isolated from soil - plant growth promoting and disease suppressive microbes used as inoculants, foliar inoculants for improvement of ruminant digestion systems and inoculants used in bioremediation of toxic compounds in the environment. Soil biodiversity is highly recognised now as an important feature of healthy soil and imbalances have been shown to give advantage to harmful over beneficial organisms. This presentation will highlight the many connections of biodiversity to soil quality and human health.

Classification of thermophilic actinobacteria isolated from arid desert soils, including the description of Amycolatopsis deserti sp. nov.

PubMed

Busarakam, Kanungnid; Brown, Ros; Bull, Alan T; Tan, Geok Yuan Annie; Zucchi, Tiago D; da Silva, Leonardo José; de Souza, Wallace Rafael; Goodfellow, Michael

2016-02-01

The taxonomic position of 26 filamentous actinobacteria isolated from a hyper-arid Atacama Desert soil and 2 from an arid Australian composite soil was established using a polyphasic approach. All of the isolates gave the diagnostic amplification product using 16S rRNA oligonucleotide primers specific for the genus Amycolatopsis. Representative isolates had chemotaxonomic and morphological properties typical of members of the genus Amycolatopsis. 16S rRNA gene analyses showed that all of the isolates belong to the Amycolatopsis methanolica 16S rRNA gene clade. The Atacama Desert isolates were assigned to one or other of two recognised species, namely Amycolatopsis ruanii and Amycolatopsis thermalba, based on 16S rRNA gene sequence, DNA:DNA relatedness and phenotypic data; emended descriptions are given for these species. In contrast, the two strains from the arid Australian composite soil, isolates GY024(T) and GY142, formed a distinct branch at the periphery of the A. methanolica 16S rRNA phyletic line, a taxon that was supported by all of the tree-making algorithms and by a 100 % bootstrap value. These strains shared a high degree of DNA:DNA relatedness and have many phenotypic properties in common, some of which distinguished them from all of the constituent species classified in the A. methanolica 16S rRNA clade. Isolates GY024(T) and GY142 merit recognition as a new species within the A. methanolica group of thermophilic strains. The name proposed for the new species is Amycolatopsis deserti sp. nov.; the type strain is GY024(T) (=NCIMB 14972(T) = NRRL B-65266(T)).

[Zoological diagnostics of soils: imperatives, purposes, and place within soil zoology and pedology].

PubMed

Mordokovich, V G

2013-01-01

Zoological diagnostics of soils was conceived by M.S. Ghilarov as a part of soil zoology and intended to be closely related to pedology. He considered zoo-agents as an ecological factor, one among many others, of soil formation. Contemporary soil diagnostics pursues mostly utilitarian goals and is based on conservative properties of the stable part of soil substrate. However, it is admitted that these properties are generated by specific combinations of biological, chemical, and physical phenomena that are called "elementary soil processes" (ESP) and occur nowhere but in soils. Certain ESPs are associated with distinctive combinations of biota, including invertebrates. Pedobionts act as producers of detritus and contribute to humus formation, which is necessary for any ESP starting, thus being its active party. That is why animals, being the most complex and active part of the ESP system, may be treated not only as its indicators but also as its navigators. Monitoring and studying of ESPs in soil is complicated because of inevitable disturbance of soil profile natural composition. Zoo-agents, at the same time, can be registered without habitats changing. Taking into account ecological potency of soil invertebrates that participate in an ESP, spectra of their eco-groups, life forms, and results of their activity, it is possible to diagnose a soil state at different stages of certain ESPs development, with their different combinations, and in different regions or parts of natural environmental gradients.

Soil quality and soil degradation in agricultural loess soils in Central Europe - impacts of traditional small-scale and modernized large-scale agriculture

NASA Astrophysics Data System (ADS)

Schneider, Christian

2017-04-01

The study analyzes the impact of different farming systems on soil quality and soil degradation in European loess landscapes. The analyses are based on geo-chemical soil properties, landscape metrics and geomorphological indicators. The German Middle Saxonian Loess Region represents loess landscapes whose ecological functions were shaped by land consolidation measures resulting in large-scale high-input farming systems. The Polish Proszowice Plateau is still characterized by a traditional small-scale peasant agriculture. The research areas were analyzed on different scale levels combining GIS, field, and laboratory methods. A digital terrain classification was used to identify representative catchment basins for detailed pedological studies which were focused on soil properties that responded to soil management within several years, like pH-value, total carbon (TC), total nitrogen (TN), inorganic carbon (IC), soil organic carbon (TOC=TC-IC), hot-water extractable carbon (HWC), hot-water extractable nitrogen (HWN), total phosphorus, plant-available phosphorus (P), plant-available potassium (K) and the potential cation exchange capacity (CEC). The study has shown that significant differences in major soil properties can be observed because of different fertilizer inputs and partly because of different cultivation techniques. Also the traditional system increases soil heterogeneity. Contrary to expectations the study has shown that the small-scale peasant farming system resulted in similar mean soil organic carbon and phosphorus contents like the industrialized high-input farming system. A further study could include investigations of the effects of soil amendments like herbicides and pesticide on soil degradation.

Why Devil's town has Devil's water

NASA Astrophysics Data System (ADS)

Jovic, Sladjana; Mitriceski, Bojana

2015-04-01

Why Devil's town has Devil's water In the south of Serbia, lies a first-class natural landmark "Devil's Town" at an altitude of 660-700 m. Earthen figures or "towers" as the locals call them, are located in the watershed between two gullies, whose sources joined together create a unique erosive formation, tremendously demolished by the erosive processes. The gullies also have strange names: "Devil's Gully" and "Hell's Gully". There are two rare natural phenomena at the same spot: 202 earthen figures of different shape and dimension, from 2 m to 15 m in height, and from 0.5 m to 3 m in width, with stone caps on the top. They are an outcome of a specific erosive process that lasts for centuries. When figures are formed, they grow, change, shorten, gradually (very slowly) disappear and reappear. The loose soil is dissolved and washed away by the rain. However, the material under the stone caps is protected from the "bombardment" of the rain drops and washout, and remains in place in the form of the rising earthen pillars - figures. Another natural rarity in "Devil's Town" are two springs of extraordinary properties "Devil's Water", which is located in vicinity of these earthen figures, is a cold and extremely acid spring (pH 1.5) of high mineral concentration (15 g/l of water), springing out in "Devil's Gully". In comparison to drinking water, it is 10 to 1000 times richer in minerals (aluminium, iron, potassium, copper, nickel, sulphur, and alaun). "Red Well" is another spring located downstream, in the alluvial plain, 400 m away from the first spring. Its water (pH 3.5) is less acid and has a lower general mineral concentration (4.372 mg/l of water). Due to the oxidation of iron, which is contained in water in large amounts, an attractive red terrace in the form of a fan is created. The main assessment for students is to take some examples of water from Devils Gully and the others from Red Well . Second part is to find out content of minerals in water examples and

Biological framework for soil aggregation: Implications for ecological functions.

NASA Astrophysics Data System (ADS)

Ghezzehei, Teamrat; Or, Dani

2016-04-01

Soil aggregation is heuristically understood as agglomeration of primary particles bound together by biotic and abiotic cementing agents. The organization of aggregates is believed to be hierarchical in nature; whereby primary particles bond together to form secondary particles and subsequently merge to form larger aggregates. Soil aggregates are not permanent structures, they continuously change in response to internal and external forces and other drivers, including moisture, capillary pressure, temperature, biological activity, and human disturbances. Soil aggregation processes and the resulting functionality span multiple spatial and temporal scales. The intertwined biological and physical nature of soil aggregation, and the time scales involved precluded a universally applicable and quantifiable framework for characterizing the nature and function of soil aggregation. We introduce a biophysical framework of soil aggregation that considers the various modes and factors of the genesis, maturation and degradation of soil aggregates including wetting/drying cycles, soil mechanical processes, biological activity and the nature of primary soil particles. The framework attempts to disentangle mechanical (compaction and soil fragmentation) from in-situ biophysical aggregation and provides a consistent description of aggregate size, hierarchical organization, and life time. It also enables quantitative description of biotic and abiotic functions of soil aggregates including diffusion and storage of mass and energy as well as role of aggregates as hot spots of nutrient accumulation, biodiversity, and biogeochemical cycles.

Process for removing polychlorinated biphenyls from soil

DOEpatents

Hancher, C.W.; Saunders, M.B.; Googin, J.M.

1984-11-16

The present invention relates to a method of removing polychlorinated biphenyls from soil. The polychlorinated biphenyls are extracted from the soil by employing a liquid organic solvent dispersed in water in the ratio of about 1:3 to 3:1. The organic solvent includes such materials as short-chain hydrocarbons including kerosene or gasoline which are immiscible with water and are nonpolar. The organic solvent has a greater affinity for the PCB's than the soil so as to extract the PCB's from the soil upon contact. The organic solvent phase is separated from the suspended soil and water phase and distilled for permitting the recycle of the organic solvent phase and the concentration of the PCB's in the remaining organic phase. The present process can be satisfactorily practiced with soil containing 10 to 20% petroleum-based oils and organic fluids such as used in transformers and cutting fluids, coolants and the like which contain PCB's. The subject method provides for the removal of a sufficient concentration of PCB's from the soil to provide the soil with a level of PCB's within the guidelines of the Environmental Protection Agency.

Soil separator and sampler and method of sampling

DOEpatents

O'Brien, Barry H [Idaho Falls, ID; Ritter, Paul D [Idaho Falls, ID

2010-02-16

A soil sampler includes a fluidized bed for receiving a soil sample. The fluidized bed may be in communication with a vacuum for drawing air through the fluidized bed and suspending particulate matter of the soil sample in the air. In a method of sampling, the air may be drawn across a filter, separating the particulate matter. Optionally, a baffle or a cyclone may be included within the fluidized bed for disentrainment, or dedusting, so only the finest particulate matter, including asbestos, will be trapped on the filter. The filter may be removable, and may be tested to determine the content of asbestos and other hazardous particulate matter in the soil sample.

Effects of Salt Accumulation in Soil by Evaporation on Unsaturated Soil Hydraulic Properties

NASA Astrophysics Data System (ADS)

Liu, Y.; Liu, Q.

2017-12-01

Soil salinization is one type of soil degradation caused by saline groundwater evaporation. Salt accumulation in the soil will change the pore structure of soil, which should change the unsaturated soil hydraulic properties including the soil water characteristic curve (SWCC). To investigate the effect of salt accumulation on the SWCC and find the best suitable SWCC model to characterize the relationship of soil moisture and soil matrix potential, we have conducted laboratory SWCC experiments with the soil columns saturated by NaCl solution with different concentration (deionized water, 3 g/L, 15 g/L, 50 g/L, 100 g/L and 200 g/L). As the concentration of initial solution increases, the matrix potential corresponding to the same moisture increases. As the water was evaporated, the salt would precipitate in soil continuously, which would decrease the porosity of soils and increase the negative pressure of soils. With higher initial concentration, the more salt accumulation caused the more residual water content in the soils. For van Genuchten-Mualem model, the residual water contents θr were 0.0159, 0.0181, 0.0182, 0.0328, 0.0312, 0.0723, 0.0864 in the columns initially saturated by deionized water, 3 g/L, 15 g/L, 50 g/L, 100 g/L and 200 g/L, respectively. The van Genuchten-Mualem model, Fredlund-Xing model, Gardern model, Mckee-Bumb model and Brooks-Corey model were fitted by MATLAB with the experiments data, and the fitted coefficients were compared. The Fredlund-Xing model has the best fitting coefficients and the calculated value was consistent with the observed data.

iSOIL: Interactions between soil related sciences - Linking geophysics, soil science and digital soil mapping

NASA Astrophysics Data System (ADS)

Dietrich, Peter; Werban, Ulrike; Sauer, Uta

2010-05-01

High-resolution soil property maps are one major prerequisite for the specific protection of soil functions and restoration of degraded soils as well as sustainable land use, water and environmental management. To generate such maps the combination of digital soil mapping approaches and remote as well as proximal soil sensing techniques is most promising. However, a feasible and reliable combination of these technologies for the investigation of large areas (e.g. catchments and landscapes) and the assessment of soil degradation threats is missing. Furthermore, there is insufficient dissemination of knowledge on digital soil mapping and proximal soil sensing in the scientific community, to relevant authorities as well as prospective users. As one consequence there is inadequate standardization of techniques. At the poster we present the EU collaborative project iSOIL within the 7th framework program of the European Commission. iSOIL focuses on improving fast and reliable mapping methods of soil properties, soil functions and soil degradation risks. This requires the improvement and integration of advanced soil sampling approaches, geophysical and spectroscopic measuring techniques, as well as pedometric and pedophysical approaches. The focus of the iSOIL project is to develop new and to improve existing strategies and innovative methods for generating accurate, high resolution soil property maps. At the same time the developments will reduce costs compared to traditional soil mapping. ISOIL tackles the challenges by the integration of three major components: (i)high resolution, non-destructive geophysical (e.g. Electromagnetic Induction EMI; Ground Penetrating Radar, GPR; magnetics, seismics) and spectroscopic (e.g., Near Surface Infrared, NIR) methods, (ii)Concepts of Digital Soil Mapping (DSM) and pedometrics as well as (iii)optimized soil sampling with respect to profound soil scientific and (geo)statistical strategies. A special focus of iSOIL lies on the

A first attempt to reproduce basaltic soil chronosequences using a process-based soil profile model: implications for our understanding of soil evolution

NASA Astrophysics Data System (ADS)

Johnson, M.; Gloor, M.; Lloyd, J.

2012-04-01

Soils are complex systems which hold a wealth of information on both current and past conditions and many biogeochemical processes. The ability to model soil forming processes and predict soil properties will enable us to quantify such conditions and contribute to our understanding of long-term biogeochemical cycles, particularly the carbon cycle and plant nutrient cycles. However, attempts to confront such soil model predictions with data are rare, although increasingly more data from chronosquence studies is becoming available for such a purpose. Here we present initial results of an attempt to reproduce soil properties with a process-based soil evolution model similar to the model of Kirkby (1985, J. Soil Science). We specifically focus on the basaltic soils in both Hawaii and north Queensland, Australia. These soils are formed on a series of volcanic lava flows which provide sequences of different aged soils all with a relatively uniform parent material. These soil chronosequences provide a snapshot of a soil profile during different stages of development. Steep rainfall gradients in these regions also provide a system which allows us to test the model's ability to reproduce soil properties under differing climates. The mechanistic, soil evolution model presented here includes the major processes of soil formation such as i) mineral weathering, ii) percolation of rainfall through the soil, iii) leaching of solutes out of the soil profile iv) surface erosion and v) vegetation and biotic interactions. The model consists of a vertical profile and assumes simple geometry with a constantly sloping surface. The timescales of interest are on the order of tens to hundreds of thousand years. The specific properties the model predicts are, soil depth, the proportion of original elemental oxides remaining in each soil layer, pH of the soil solution, organic carbon distribution and CO2 production and concentration. The presentation will focus on a brief introduction of the

Consensus on a new definition for soil?

USDA-ARS?s Scientific Manuscript database

Unconsolidated material does not become soil without biological input. Until it is proven that life forms exist on extraterrestrial planets and moons, these should not be considered "soils" in context of soil formation, which includes the organism factor. There is already a perfectly good term for w...

Surface Soil Moisture Estimates Across China Based on Multi-satellite Observations and A Soil Moisture Model

NASA Astrophysics Data System (ADS)

Zhang, Ke; Yang, Tao; Ye, Jinyin; Li, Zhijia; Yu, Zhongbo

2017-04-01

Soil moisture is a key variable that regulates exchanges of water and energy between land surface and atmosphere. Soil moisture retrievals based on microwave satellite remote sensing have made it possible to estimate global surface (up to about 10 cm in depth) soil moisture routinely. Although there are many satellites operating, including NASA's Soil Moisture Acitive Passive mission (SMAP), ESA's Soil Moisture and Ocean Salinity mission (SMOS), JAXA's Advanced Microwave Scanning Radiometer 2 mission (AMSR2), and China's Fengyun (FY) missions, key differences exist between different satellite-based soil moisture products. In this study, we applied a single-channel soil moisture retrieval model forced by multiple sources of satellite brightness temperature observations to estimate consistent daily surface soil moisture across China at a spatial resolution of 25 km. By utilizing observations from multiple satellites, we are able to estimate daily soil moisture across the whole domain of China. We further developed a daily soil moisture accounting model and applied it to downscale the 25-km satellite-based soil moisture to 5 km. By comparing our estimated soil moisture with observations from a dense observation network implemented in Anhui Province, China, our estimated soil moisture results show a reasonably good agreement with the observations (RMSE < 0.1 and r > 0.8).

Status of domestic wastewater management in relation to drinking-water supply in two states of India.

PubMed

Pandey, R A; Kaul, S N

2000-01-01

In India, supply of drinking water, treatment and disposal of domestic wastewater including faecal matter are managed by local bodies. The existing status of water supply, characteristics of domestic wastewater, modes of collection, treatment and disposal system for sewage and faecal matter in 82 municipalities and 4 municipal corporations were assessed in the States of Bihar and West Bengal in India. Domestic wastewater in the municipal areas is collected and discharged through open kachha (earthen), pucca (cement-concrete) and natural drains and discharged into water courses or disposed on land. Scavenger carriage system for night soil disposal is in-vogue at several places in the surveyed States. Open defecation by the inhabitants in some of the municipalities also occurs. The existing methods of collection, treatment and disposal of sewage impairs the water quality of different water sources. Techno-economically viable remedial measures for providing basic amenities, namely safe drinking-water supply and proper sanitation to the communities of these two States of India are suggested and discussed.

Identification and behavior of collapsible soils : [technical summary].

DOT National Transportation Integrated Search

2011-01-01

Collapsible soils are susceptible to large volumetric strains when they become saturated. Numerous soil types : fall in the general category of collapsible soils, including : loess, a well-known aeolian deposit, present throughout : most of Indiana. ...

Effects of soil depth and plant-soil interaction on microbial community in temperate grasslands of northern China.

PubMed

Yao, Xiaodong; Zhang, Naili; Zeng, Hui; Wang, Wei

2018-07-15

Although the patterns and drivers of soil microbial community composition are well studied, little is known about the effects of plant-soil interactions and soil depth on soil microbial distribution at a regional scale. We examined 195 soil samples from 13 sites along a climatic transect in the temperate grasslands of northern China to measure the composition of and factors influencing soil microbial communities within a 1-m soil profile. Soil microbial community composition was measured using phospholipid fatty acids (PLFA) analysis. Fungi predominated in topsoil (0-10 cm) and bacteria and actinomycetes in deep soils (40-100 cm), independent of steppe types. This variation was explained by contemporary environmental factors (including above- and below-ground plant biomass, soil physicochemical and climatic factors) >58% in the 0-40 cm of soil depth, but <45% in deep soils. Interestingly, when we considered the interactive effects between plant traits (above ground biomass and root biomass) and soil factors (pH, clay content, and soil total carbon, nitrogen, phosphorous), we observed a significant interaction effect occurring at depths of 10-20 cm soil layer, due to different internal and external factors of the plant-soil system along the soil profile. These results improve understanding of the drivers of soil microbial community composition at regional scales. Copyright © 2018 Elsevier B.V. All rights reserved.

Relevant magnetic and soil parameters as potential indicators of soil conservation status of Mediterranean agroecosystems

NASA Astrophysics Data System (ADS)

Quijano, Laura; Chaparro, Marcos A. E.; Marié, Débora C.; Gaspar, Leticia; Navas, Ana

2014-09-01

The main sources of magnetic minerals in soils unaffected by anthropogenic pollution are iron oxides and hydroxides derived from parent materials through soil formation processes. Soil magnetic minerals can be used as indicators of environmental factors including soil forming processes, degree of pedogenesis, weathering processes and biological activities. In this study measurements of magnetic susceptibility are used to detect the presence and the concentration of soil magnetic minerals in topsoil and bulk samples in a small cultivated field, which forms a hydrological unit that can be considered to be representative of the rainfed agroecosystems of Mediterranean mountain environments. Additional magnetic studies such as isothermal remanent magnetization (IRM), anhysteretic remanent magnetization (ARM) and thermomagnetic measurements are used to identify and characterize the magnetic mineralogy of soil minerals. The objectives were to analyse the spatial variability of the magnetic parameters to assess whether topographic factors, soil redistribution processes, and soil properties such as soil texture, organic matter and carbonate contents analysed in this study, are related to the spatial distribution pattern of magnetic properties. The medians of mass specific magnetic susceptibility at low frequency (χlf) were 36.0 and 31.1 × 10-8 m3 kg-1 in bulk and topsoil samples respectively. High correlation coefficients were found between the χlf in topsoil and bulk core samples (r = 0.951, p < 0.01). In addition, volumetric magnetic susceptibility was measured in situ in the field (κis) and values varied from 13.3 to 64.0 × 10-5 SI. High correlation coefficients were found between χlf in topsoil measured in the laboratory and volumetric magnetic susceptibility field measurements (r = 0.894, p < 0.01). The results obtained from magnetic studies such as IRM, ARM and thermomagnetic measurements show the presence of magnetite, which is the predominant magnetic carrier

Proceedings of the Alaska forest soil productivity workshop.

Treesearch

C.W. Slaughter; T. Gasbarro

1988-01-01

The Alaska Forest Soil Productivity Workshop addressed (1) the role of soil information for forest management in Alaska; (2) assessment, monitoring, and enhancement of soil productivity; and (3) Alaska research projects involved in studies of productivity of forests and soils. This proceedings includes 27 papers in five categories: agency objectives in monitoring and...

Active Layer Soil Carbon and Nutrient Mineralization, Barrow, Alaska, 2012

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stan D. Wullschleger; Holly M. Vander Stel; Colleen Iversen

This data set consists of bulk soil characteristics as well as carbon and nutrient mineralization rates of active layer soils manually collected from the field in August, 2012, frozen, and then thawed and incubated across a range of temperatures in the laboratory for 28 day periods in 2013-2015. The soils were collected from four replicate polygons in each of the four Areas (A, B, C, and D) of Intensive Site 1 at the Next-Generation Ecosystem Experiments (NGEE) Arctic site near Barrow, Alaska. Soil samples were coincident with the established Vegetation Plots that are located in center, edge, and trough microtopographymore » in each polygon. Data included are 1) bulk soil characteristics including carbon, nitrogen, gravimetric water content, bulk density, and pH in 5-cm depth increments and also by soil horizon, 2) carbon, nitrogen, and phosphorus mineralization rates for soil horizons incubated aerobically (and in one case both aerobically and anaerobically) for 28 days at temperatures that included 2, 4, 8, and 12 degrees C. Additional soil and incubation data are forthcoming. They will be available when published as part of another paper that includes additional replicate analyses.« less

Effective Classroom Demonstration of Soil Reinforcing Techniques.

ERIC Educational Resources Information Center

Williams, John Wharton; Fox, Dennis James

1986-01-01

Presents a model for demonstrating soil mass stabilization. Explains how this approach can assist students in understanding the various types of soil reinforcement techniques, their relative contribution to increased soil strength, and some of their limitations. A working drawing of the model and directives for construction are included. (ML)

SoilGrids250m: Global gridded soil information based on machine learning

PubMed Central

Mendes de Jesus, Jorge; Heuvelink, Gerard B. M.; Ruiperez Gonzalez, Maria; Kilibarda, Milan; Blagotić, Aleksandar; Shangguan, Wei; Wright, Marvin N.; Geng, Xiaoyuan; Bauer-Marschallinger, Bernhard; Guevara, Mario Antonio; Vargas, Rodrigo; MacMillan, Robert A.; Batjes, Niels H.; Leenaars, Johan G. B.; Ribeiro, Eloi; Wheeler, Ichsani; Mantel, Stephan; Kempen, Bas

2017-01-01

This paper describes the technical development and accuracy assessment of the most recent and improved version of the SoilGrids system at 250m resolution (June 2016 update). SoilGrids provides global predictions for standard numeric soil properties (organic carbon, bulk density, Cation Exchange Capacity (CEC), pH, soil texture fractions and coarse fragments) at seven standard depths (0, 5, 15, 30, 60, 100 and 200 cm), in addition to predictions of depth to bedrock and distribution of soil classes based on the World Reference Base (WRB) and USDA classification systems (ca. 280 raster layers in total). Predictions were based on ca. 150,000 soil profiles used for training and a stack of 158 remote sensing-based soil covariates (primarily derived from MODIS land products, SRTM DEM derivatives, climatic images and global landform and lithology maps), which were used to fit an ensemble of machine learning methods—random forest and gradient boosting and/or multinomial logistic regression—as implemented in the R packages ranger, xgboost, nnet and caret. The results of 10–fold cross-validation show that the ensemble models explain between 56% (coarse fragments) and 83% (pH) of variation with an overall average of 61%. Improvements in the relative accuracy considering the amount of variation explained, in comparison to the previous version of SoilGrids at 1 km spatial resolution, range from 60 to 230%. Improvements can be attributed to: (1) the use of machine learning instead of linear regression, (2) to considerable investments in preparing finer resolution covariate layers and (3) to insertion of additional soil profiles. Further development of SoilGrids could include refinement of methods to incorporate input uncertainties and derivation of posterior probability distributions (per pixel), and further automation of spatial modeling so that soil maps can be generated for potentially hundreds of soil variables. Another area of future research is the development of

SoilGrids250m: Global gridded soil information based on machine learning.

PubMed

Hengl, Tomislav; Mendes de Jesus, Jorge; Heuvelink, Gerard B M; Ruiperez Gonzalez, Maria; Kilibarda, Milan; Blagotić, Aleksandar; Shangguan, Wei; Wright, Marvin N; Geng, Xiaoyuan; Bauer-Marschallinger, Bernhard; Guevara, Mario Antonio; Vargas, Rodrigo; MacMillan, Robert A; Batjes, Niels H; Leenaars, Johan G B; Ribeiro, Eloi; Wheeler, Ichsani; Mantel, Stephan; Kempen, Bas

2017-01-01

This paper describes the technical development and accuracy assessment of the most recent and improved version of the SoilGrids system at 250m resolution (June 2016 update). SoilGrids provides global predictions for standard numeric soil properties (organic carbon, bulk density, Cation Exchange Capacity (CEC), pH, soil texture fractions and coarse fragments) at seven standard depths (0, 5, 15, 30, 60, 100 and 200 cm), in addition to predictions of depth to bedrock and distribution of soil classes based on the World Reference Base (WRB) and USDA classification systems (ca. 280 raster layers in total). Predictions were based on ca. 150,000 soil profiles used for training and a stack of 158 remote sensing-based soil covariates (primarily derived from MODIS land products, SRTM DEM derivatives, climatic images and global landform and lithology maps), which were used to fit an ensemble of machine learning methods-random forest and gradient boosting and/or multinomial logistic regression-as implemented in the R packages ranger, xgboost, nnet and caret. The results of 10-fold cross-validation show that the ensemble models explain between 56% (coarse fragments) and 83% (pH) of variation with an overall average of 61%. Improvements in the relative accuracy considering the amount of variation explained, in comparison to the previous version of SoilGrids at 1 km spatial resolution, range from 60 to 230%. Improvements can be attributed to: (1) the use of machine learning instead of linear regression, (2) to considerable investments in preparing finer resolution covariate layers and (3) to insertion of additional soil profiles. Further development of SoilGrids could include refinement of methods to incorporate input uncertainties and derivation of posterior probability distributions (per pixel), and further automation of spatial modeling so that soil maps can be generated for potentially hundreds of soil variables. Another area of future research is the development of methods

Effect of variable soil texture, metal saturation of soil organic matter (SOM) and tree species composition on spatial distribution of SOM in forest soils in Poland.

PubMed

Gruba, Piotr; Socha, Jarosław; Błońska, Ewa; Lasota, Jarosław

2015-07-15

In this study we investigated the effect of fine (ϕ<0.05mm) fraction, i.e., silt+clay (FF) content in soils, site moisture, metal (Al and Fe) of soil organic matter (SOM) and forest species composition on the spatial distribution of carbon (C) pools in forest soils at the landscape scale. We established 275 plots in regular 200×200m grid in a forested area of 14.4km(2). Fieldwork included soil sampling of the organic horizon, mineral topsoil and subsoil down to 40cm deep. We analysed the vertical and horizontal distribution of soil organic carbon (SOC) stocks, as well as the quantity of physically separated fractions including the free light (fLF), occluded light (oLF) and mineral associated fractions (MAF) in the mineral topsoil (A, AE) horizons. Distribution of C in soils was predominantly affected by the variation in the FF content. In soils richer in the FF more SOC was accumulated in mineral horizons and less in the organic horizons. Accumulation of SOC in mineral soil was also positively affected by the degree of saturation of SOM with Al and Fe. The increasing share of beech influenced the distribution of C stock in soil profiles by reducing the depth of O horizon and increasing C stored in mineral soil. The content of FF was positively correlated with the content of C in MAF and fLF fractions. The content of oLF and MAF fractions was also positively influenced by a higher degree of metal saturation, particularly Al. Our results confirmed that Al plays an important role in the stabilization of SOM inside aggregates (CoLF) and as in CMAF fractions. We also found a significant, positive effect of beech on the CfLF and fir on the CoLF content. Copyright © 2015 Elsevier B.V. All rights reserved.

Policy and effective action for soil security: a need for reframing the soil story

NASA Astrophysics Data System (ADS)

Bouma, Johan

2015-07-01

Soil science is a vital scientific discipline producing cutting-edge research in its various sub-disciplines. Its role in studying major environmental issues, often defined as food security, water and energy availability, climate change and biodiversity loss, is, however, less obvious to stakeholders, policy makers and the public at large. It deserves better. Reframing the soil story by taking a pro-active interdisciplinary approach in demonstrating the role of soils when studying these issues is advocated in the context of the ten Sustainable Development Goals. Soil change matters not only in a negative way when referring to erosion and degradation but also, and particularly, to soil improvement. But only successfully completed programs in practice will be convincing and that's why an active role of soil researchers and soil scientists, acting as knowledge brokers, is advocated in transdisciplinary programs. This includes more emphasis on preparation and implementation than is allowed in current programs. A case study is presented and a narrative is used to link the five major environmental issues in a logical sequence, showing their interdependence. Current soil research and education programs should reflect demands made by inter- and transdisciplinary approaches and need a new, fresh approach.

Changes in the structure and function of soil ecosystems in soils contaminated with heavy metals

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kuperman, R.; Parmelee, R.; Carreiro, M.

1995-09-01

The structure and function of soil communities in an area with a wide range of concentrations of heavy metals was studied in portions of the U.S. Army`s Aberdeen Proving Ground, Maryland. The study included survey of soil macro- and microinvertebrate communities, soil microorganisms, enzyme activities and the rates of nutrient dynamics in soil. Soil macroinvertebrate communities showed significant reductions in the adundance of several taxonomic and functional groups in contaminated areas. The total numbers of nematodes and numbers of fungivore, bacterivore and omnivore-predator nematodes were lower in the more contaminated areas. The numbers of active bacteria and fungi were lowermore » in areas of soil contamination. Significant reduction in the activities of all enzymes closely paralleled the increase in heavy metal concentrations. Ten-to-fifty fold reductions in enzyme activities were observed as heavy metal concentrations increased. These results suggest that soil contamination with heavy metals may have detrimental effects on soil biota and the rates of organic matter degradation and subsequent release of nutrients to aboveground communities in the area.« less

Changes in the structure and function of soil ecosystems in soils contaminated with heavy metals

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kuperman, R.; Parmelee, R.; Carreiro, M.

1995-06-01

The structure and function of soil communities in an area with a wide range of concentrations of heavy metals was studied in portions of the U.S. Army`s Aberdeen Proving Ground, Maryland. The study included survey of soil macro- and microinvertebrate communities, soil microorganisms, enzyme activities and the rates of nutrient dynamics in soil. Soil macroinvertebrate communities showed significant reductions in the abundance of several taxonomic and functional groups in contaminated areas. The total numbers of nematodes and numbers of fungivore, bacterivore and omnivore-predator nematodes were lower in the more contaminated areas. The numbers of active bacteria and fungi were lowermore » in areas of soil contamination. Significant reduction in the activities of all enzymes closely paralleled the increase in heavy metal concentrations. Ten-to-fifty fold reductions in enzyme activities were observed as heavy metal concentrations increased. These results suggest that soil contamination with heavy metals may have detrimental effects on soil biota and the rates of organic matter degradation and subsequent release of nutrients to aboveground communities in the area.« less

Relationship between the erosion properties of soils and other parameters

USDA-ARS?s Scientific Manuscript database

Soil parameters are essential for erosion process prediction and ultimately improved model development, especially as they relate to dam and levee failure. Soil parameters including soil texture and structure, soil classification, soil compaction, moisture content, and degree of saturation can play...

Soil invertebrate fauna affect N2 O emissions from soil.

PubMed

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

2013-09-01

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 < 0.001), but the cumulative N2 O emissions remained unaffected. We propose that increased 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. © 2013 John Wiley & Sons Ltd.

Calcic soils and calcretes in the southwestern United States

USGS Publications Warehouse

Bachman, George Odell; Machette, Michael N.

1977-01-01

Secondary calcium carbonate of diverse origins, 'caliche' of many authors, is widespread in the southwestern United States. 'Caliche' includes various carbonates such as calcic soils and products of groundwater cementation. The term 'caliche' is generally avoided in this report in favor of such terms as calcrete, calcic soils, and pervasively cemented deposits. Criteria for the recognition of various types of calcrete of diverse origins include field relations and laboratory data. Calcic soils provide a comprehensive set of characteristics that aid in their recognition in the field. These characteristics include a distinctive morphology that is zoned horizontally and can frequently be traced over tens to hundreds of square kilometers. The major process in the formation of pedogenic calcrete and calic soils is the leaching of calcium carbonate from upper soil horizons by downward percolating soil solutions and reprecipitation of the carbonate in alluvial horizons near the base of the soil profile. The formation of pedogenic calcrete involves many factors including climate, source of carbonate, and tectonic stability of the geomorphic surface on which the calcrete is deposited. Most of the carbonate in pedogenic calcrete is probably derived from windblown sand, dust, and rain. Calcic soils and pedogenic calcretes follow a six-stage sequence morphologic development and is based on a classification devised by Gile, Peterson and Grossman in 1966. The .six morphologic stages of carbonate deposition in soils are related to the relative age of the soil and are as follows: I. The first or youngest stage includes filamentous or faint coatings of carbonate on detrital grains. II. The second stage includes pebble coatings which are continuous; firm carbonate nodules are few to common. III. The third stage includes coalesced nodules which occur in a friable or disseminated carbonate matrix. IV. The fourth stage includes platy, firmly cemented matrix which engulfs nodules

Soil Penetration by Earthworms and Plant Roots—Mechanical Energetics of Bioturbation of Compacted Soils

PubMed Central

2015-01-01

We quantify mechanical processes common to soil penetration by earthworms and growing plant roots, including the energetic requirements for soil plastic displacement. The basic mechanical model considers cavity expansion into a plastic wet soil involving wedging by root tips or earthworms via cone-like penetration followed by cavity expansion due to pressurized earthworm hydroskeleton or root radial growth. The mechanical stresses and resulting soil strains determine the mechanical energy required for bioturbation under different soil hydro-mechanical conditions for a realistic range of root/earthworm geometries. Modeling results suggest that higher soil water content and reduced clay content reduce the strain energy required for soil penetration. The critical earthworm or root pressure increases with increased diameter of root or earthworm, however, results are insensitive to the cone apex (shape of the tip). The invested mechanical energy per unit length increase with increasing earthworm and plant root diameters, whereas mechanical energy per unit of displaced soil volume decreases with larger diameters. The study provides a quantitative framework for estimating energy requirements for soil penetration work done by earthworms and plant roots, and delineates intrinsic and external mechanical limits for bioturbation processes. Estimated energy requirements for earthworm biopore networks are linked to consumption of soil organic matter and suggest that earthworm populations are likely to consume a significant fraction of ecosystem net primary production to sustain their subterranean activities. PMID:26087130

How do peat type, sand addition and soil moisture influence the soil organic matter mineralization in anthropogenically disturbed organic soils?

NASA Astrophysics Data System (ADS)

Säurich, Annelie; Tiemeyer, Bärbel; Don, Axel; Burkart, Stefan

2017-04-01

Drained peatlands are hotspots of carbon dioxide (CO2) emissions from agriculture. As a consequence of both drainage induced mineralization and anthropogenic sand mixing, large areas of former peatlands under agricultural use contain soil organic carbon (SOC) at the boundary between mineral and organic soils. Studies on SOC dynamics of such "low carbon organic soils" are rare as the focus of previous studies was mainly either on mineral soils or "true" peat soil. However, the variability of CO2 emissions increases with disturbance and therefore, we have yet to understand the reasons behind the relatively high CO2 emissions of these soils. Peat properties, soil organic matter (SOM) quality and water content are obviously influencing the rate of CO2 emissions, but a systematic evaluation of the hydrological and biogeochemical drivers for mineralization of disturbed peatlands is missing. With this incubation experiment, we aim at assessing the drivers of the high variability of CO2 emissions from strongly anthropogenically disturbed organic soil by systematically comparing strongly degraded peat with and without addition of sand under different moisture conditions and for different peat types. The selection of samples was based on results of a previous incubation study, using disturbed samples from the German Agricultural Soil Inventory. We sampled undisturbed soil columns from topsoil and subsoil (three replicates of each) of ten peatland sites all used as grassland. Peat types comprise six fens (sedge, Phragmites and wood peat) and four bogs (Sphagnum peat). All sites have an intact peat horizon that is permanently below groundwater level and a strongly disturbed topsoil horizon. Three of the fen and two of the bog sites have a topsoil horizon altered by sand-mixing. In addition the soil profile was mapped and samples for the determination of soil hydraulic properties were collected. All 64 soil columns (including four additional reference samples) will be installed

The History of Electromagnetic Induction Techniques in Soil Survey

NASA Astrophysics Data System (ADS)

Brevik, Eric C.; Doolittle, Jim

2014-05-01

Electromagnetic induction (EMI) has been used to characterize the spatial variability of soil properties since the late 1970s. Initially used to assess soil salinity, the use of EMI in soil studies has expanded to include: mapping soil types; characterizing soil water content and flow patterns; assessing variations in soil texture, compaction, organic matter content, and pH; and determining the depth to subsurface horizons, stratigraphic layers or bedrock, among other uses. In all cases the soil property being investigated must influence soil apparent electrical conductivity (ECa) either directly or indirectly for EMI techniques to be effective. An increasing number and diversity of EMI sensors have been developed in response to users' needs and the availability of allied technologies, which have greatly improved the functionality of these tools. EMI investigations provide several benefits for soil studies. The large amount of georeferenced data that can be rapidly and inexpensively collected with EMI provides more complete characterization of the spatial variations in soil properties than traditional sampling techniques. In addition, compared to traditional soil survey methods, EMI can more effectively characterize diffuse soil boundaries and identify included areas of dissimilar soils within mapped soil units, giving soil scientists greater confidence when collecting spatial soil information. EMI techniques do have limitations; results are site-specific and can vary depending on the complex interactions among multiple and variable soil properties. Despite this, EMI techniques are increasingly being used to investigate the spatial variability of soil properties at field and landscape scales.

An Overview of Soils and Human Health

NASA Astrophysics Data System (ADS)

Brevik, Eric C.

2013-04-01

Few people recognize the connection between soils and human health, even though soils are actually very important to health. Soils influence health through the nutrients taken up by plants and the animals that eat those plants, nutrients that are needed for adequate nutrition for growth and development. Soils can also act to harm human health in three major ways: i) toxic levels of substances or disease-causing organisms may enter the human food chain from the soil ii) humans can encounter pathogenic organisms through direct contact with the soil or inhaling dust from the soil, and iii) degraded soils produce nutrient-deficient foods leading to malnutrition. Soils have also been a major source of medicines. Therefore, soils form an integral link in the holistic view of human health. In this presentation, soils and their influence on human health are discussed from a broad perspective, including both direct influences of soils on health and indirect influences through things such as climate change, occupational exposure to soil amendments, and the role of soils in providing food security.

Assessment the effect of homogenized soil on soil hydraulic properties and soil water transport

NASA Astrophysics Data System (ADS)

Mohawesh, O.; Janssen, M.; Maaitah, O.; Lennartz, B.

2017-09-01

Soil hydraulic properties play a crucial role in simulating water flow and contaminant transport. Soil hydraulic properties are commonly measured using homogenized soil samples. However, soil structure has a significant effect on the soil ability to retain and to conduct water, particularly in aggregated soils. In order to determine the effect of soil homogenization on soil hydraulic properties and soil water transport, undisturbed soil samples were carefully collected. Five different soil structures were identified: Angular-blocky, Crumble, Angular-blocky (different soil texture), Granular, and subangular-blocky. The soil hydraulic properties were determined for undisturbed and homogenized soil samples for each soil structure. The soil hydraulic properties were used to model soil water transport using HYDRUS-1D.The homogenized soil samples showed a significant increase in wide pores (wCP) and a decrease in narrow pores (nCP). The wCP increased by 95.6, 141.2, 391.6, 3.9, 261.3%, and nCP decreased by 69.5, 10.5, 33.8, 72.7, and 39.3% for homogenized soil samples compared to undisturbed soil samples. The soil water retention curves exhibited a significant decrease in water holding capacity for homogenized soil samples compared with the undisturbed soil samples. The homogenized soil samples showed also a decrease in soil hydraulic conductivity. The simulated results showed that water movement and distribution were affected by soil homogenizing. Moreover, soil homogenizing affected soil hydraulic properties and soil water transport. However, field studies are being needed to find the effect of these differences on water, chemical, and pollutant transport under several scenarios.

Improving the relationship between soil characteristics and metal bioavailability by using reactive fractions of soil parameters in calcareous soils.

PubMed

de Santiago-Martín, Ana; van Oort, Folkert; González, Concepción; Quintana, José R; Lafuente, Antonio L; Lamy, Isabelle

2015-01-01

The contribution of the nature instead of the total content of soil parameters relevant to metal bioavailability in lettuce was tested using a series of low-polluted Mediterranean agricultural calcareous soils offering natural gradients in the content and composition of carbonate, organic, and oxide fractions. Two datasets were compared by canonical ordination based on redundancy analysis: total concentrations (TC dataset) of main soil parameters (constituents, phases, or elements) involved in metal retention and bioavailability; and chemically defined reactive fractions of these parameters (RF dataset). The metal bioavailability patterns were satisfactorily explained only when the RF dataset was used, and the results showed that the proportion of crystalline Fe oxides, dissolved organic C, diethylene-triamine-pentaacetic acid (DTPA)-extractable Cu and Zn, and a labile organic pool accounted for 76% of the variance. In addition, 2 multipollution scenarios by metal spiking were tested that showed better relationships with the RF dataset than with the TC dataset (up to 17% more) and new reactive fractions involved. For Mediterranean calcareous soils, the use of reactive pools of soil parameters rather than their total contents improved the relationships between soil constituents and metal bioavailability. Such pool determinations should be systematically included in studies dealing with bioavailability or risk assessment. © 2014 SETAC.

Soil type-depending effect of paddy management: composition and distribution of soil organic matter

NASA Astrophysics Data System (ADS)

Urbanski, Livia; Kölbl, Angelika; Lehndorff, Eva; Houtermans, Miriam; Schad, Peter; Zhang, Gang-Lin; Rahayu Utami, Sri; Kögel-Knabner, Ingrid

2016-04-01

Paddy soil management is assumed to promote soil organic matter accumulation and specifically lignin caused by the resistance of the aromatic lignin structure against biodegradation under anaerobic conditions during inundation of paddy fields. The present study investigates the effect of paddy soil management on soil organic matter composition compared to agricultural soils which are not used for rice production (non-paddy soils). A variety of major soil types, were chosen in Indonesia (Java), including Alisol, Andosol and Vertisol sites (humid tropical climate of Java, Indonesia) and in China Alisol sites (humid subtropical climate, Nanjing). This soils are typically used for rice cultivation and represent a large range of soil properties to be expected in Asian paddy fields. All topsoils were analysed for their soil organic matter composition by solid-state 13C nuclear magnetic resonance spectroscopy and lignin-derived phenols by CuO oxidation method. The soil organic matter composition, revealed by solid-state 13C nuclear magnetic resonance, was similar for the above named different parent soil types (non-paddy soils) and was also not affected by the specific paddy soil management. The contribution of lignin-related carbon groups to total SOM was similar in the investigated paddy and non-paddy soils. A significant proportion of the total aromatic carbon in some paddy and non-paddy soils was attributed to the application of charcoal as a common management practise. The extraction of lignin-derived phenols revealed low VSC (vanillyl, syringyl, cinnamyl) values for all investigated soils, being typical for agricultural soils. An inherent accumulation of lignin-derived phenols due to paddy management was not found. Lignin-derived phenols seem to be soil type-dependent, shown by different VSC concentrations between the parent soil types. The specific paddy management only affects the lignin-derived phenols in Andosol-derived paddy soils which are characterized by

Soil macrofauna webmasters of ecosystem

NASA Astrophysics Data System (ADS)

Frouz, Jan

2015-04-01

The role of plant roots and microflora in shaping many ecosystem processes is generally appreciated in the contrary rho role of soil mcrofauna in this context is assumed to be negligible and rather anecdotic. But more than half of the litter fall is consumed by soil fauna and soil fauna can also consume and or translocation substantial amount of soil. Here we demonstrate on example of post mining chronosequences how site colonization by soil fauna affect composition of whole soil biota community, plant succession and soil formation. Filed and laboratory experiments show that decomposition of fauna feces may be sped up compare to litter at the very beginning but in long term fauna feces decompose slower than litter. This is also supported by micro morphological observation which shows that fauna feces form substantial part of soil. Fauna feces also induce lover or even negative priming effect when introduced in soil in comparison with litter that triggers positive priming effect. Laboratory experiment show that fauna effect is context sensitive and is more pronounced in systems already affected by soil fauna. Soil mixing by soil fauna consequently affect environmental conditions in soils such as water holding capacity or nutrient availability, it also affect composition of decomposer food web including microbial community (fungal bacterial ratio) which feed back in alternation of plant community composition during succession This fauna activity is not constant everywhere the higher effect of fauna activity on litter layer was observed in temperate soils of deciduous forests and with litter having CN between 20-30. In conclusion soil fauna use directly only small proportion of energy in the litter but can substantially affect soil carbon turnover, soil formation, decomposer food web and plant community.

Pedoinformatics Approach to Soil Text Analytics

NASA Astrophysics Data System (ADS)

Furey, J.; Seiter, J.; Davis, A.

2017-12-01

The several extant schema for the classification of soils rely on differing criteria, but the major soil science taxonomies, including the United States Department of Agriculture (USDA) and the international harmonized World Reference Base for Soil Resources systems, are based principally on inferred pedogenic properties. These taxonomies largely result from compiled individual observations of soil morphologies within soil profiles, and the vast majority of this pedologic information is contained in qualitative text descriptions. We present text mining analyses of hundreds of gigabytes of parsed text and other data in the digitally available USDA soil taxonomy documentation, the Soil Survey Geographic (SSURGO) database, and the National Cooperative Soil Survey (NCSS) soil characterization database. These analyses implemented iPython calls to Gensim modules for topic modelling, with latent semantic indexing completed down to the lowest taxon level (soil series) paragraphs. Via a custom extension of the Natural Language Toolkit (NLTK), approximately one percent of the USDA soil series descriptions were used to train a classifier for the remainder of the documents, essentially by treating soil science words as comprising a novel language. While location-specific descriptors at the soil series level are amenable to geomatics methods, unsupervised clustering of the occurrence of other soil science words did not closely follow the usual hierarchy of soil taxa. We present preliminary phrasal analyses that may account for some of these effects.

Ammonia oxidisers in a non-nitrifying Brazilian savanna soil.

PubMed

Catão, Elisa C P; Thion, Cécile; Krüger, R H; Prosser, James I

2017-11-01

Low nitrification rates in Brazilian savanna (Cerrado) soils have puzzled researchers for decades. Potential mechanisms include biological inhibitors, low pH, low microbial abundance and low soil moisture content, which hinders microbial activity, including ammonia oxidation. Two approaches were used to evaluate these potential mechanisms: (i) manipulation of soil moisture and pH in microcosms containing Cerrado soil and (ii) assessment of nitrification inhibition in slurries containing mixtures of Cerrado soil and an actively nitrifying agricultural soil. Despite high ammonium concentration in Cerrado soil microcosms, little NO3- accumulation was observed with increasing moisture or pH, but in some Cerrado soil slurries, ammonia-oxidising archaea (AOA) amoA transcripts were detected after 14 days. In mixed soil slurries, the final NO3- concentration reflected the initial proportions of agricultural and Cerrado soils in the mixture, providing no evidence of nitrification inhibitors in Cerrado soil. AOA community denaturing gradient gel electrophoresis profiles were similar in the mixed and nitrifying soils. These results suggest that nitrification in Cerrado soils is not constrained by water availability, ammonium availability, low pH or biological inhibitors, and alternative potential explanations for low nitrification levels are discussed. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Comparing ecosystem and soil respiration: Review and key challenges of tower-based and soil mesurements

USDA-ARS?s Scientific Manuscript database

The net ecosystem exchange (NEE) is the difference between ecosystem CO2 assimilation and CO2 losses to the atmosphere. Ecosystem respiration (Reco), the efflux of CO2 from the ecosystem to the atmosphere, includes the soil-to-atmosphere carbon flux (i.e., soil respiration; Rsoil) and aboveground pl...

Soil Oxidation-Reduction in Wetlands and Its Impact on Plant Functioning

PubMed Central

Pezeshki, S. R.; DeLaune, R. D.

2012-01-01

Soil flooding in wetlands is accompanied by changes in soil physical and chemical characteristics. These changes include the lowering of soil redox potential (Eh) leading to increasing demand for oxygen within the soil profile as well as production of soil phytotoxins that are by-products of soil reduction and thus, imposing potentially severe stress on plant roots. Various methods are utilized for quantifying plant responses to reducing soil conditions that include measurement of radial oxygen transport, plant enzymatic responses, and assessment of anatomical/morphological changes. However, the chemical properties and reducing nature of soil environment in which plant roots are grown, including oxygen demand, and other associated processes that occur in wetland soils, pose a challenge to evaluation and comparison of plant responses that are reported in the literature. This review emphasizes soil-plant interactions in wetlands, drawing attention to the importance of quantifying the intensity and capacity of soil reduction for proper evaluation of wetland plant responses, particularly at the process and whole-plant levels. Furthermore, while root oxygen-deficiency may partially account for plant stress responses, the importance of soil phytotoxins, produced as by-products of low soil Eh conditions, is discussed and the need for development of methods to allow differentiation of plant responses to reduced or anaerobic soil conditions vs. soil phytotoxins is emphasized. PMID:24832223

Influence of soil moisture on soil respiration

NASA Astrophysics Data System (ADS)

Fer, Miroslav; Kodesova, Radka; Nikodem, Antonin; Klement, Ales; Jelenova, Klara

2015-04-01

The aim of this work was to describe an impact of soil moisture on soil respiration. Study was performed on soil samples from morphologically diverse study site in loess region of Southern Moravia, Czech Republic. The original soil type is Haplic Chernozem, which was due to erosion changed into Regosol (steep parts) and Colluvial soil (base slope and the tributary valley). Soil samples were collected from topsoils at 5 points of the selected elevation transect and also from the parent material (loess). Grab soil samples, undisturbed soil samples (small - 100 cm3, and large - 713 cm3) and undisturbed soil blocks were taken. Basic soil properties were determined on grab soil samples. Small undisturbed soil samples were used to determine the soil water retention curves and the hydraulic conductivity functions using the multiple outflow tests in Tempe cells and a numerical inversion with HYDRUS 1-D. During experiments performed in greenhouse dry large undisturbed soil samples were wetted from below using a kaolin tank and cumulative water inflow due to capillary rise was measured. Simultaneously net CO2 exchange rate and net H2O exchange rate were measured using LCi-SD portable photosynthesis system with Soil Respiration Chamber. Numerical inversion of the measured cumulative capillary rise data using the HYDRUS-1D program was applied to modify selected soil hydraulic parameters for particular conditions and to simulate actual soil water distribution within each soil column in selected times. Undisturbed soil blocks were used to prepare thin soil sections to study soil-pore structure. Results for all soil samples showed that at the beginning of soil samples wetting the CO2 emission increased because of improving condition for microbes' activity. The maximum values were reached for soil column average soil water content between 0.10 and 0.15 cm3/cm3. Next CO2 emission decreased since the pore system starts filling by water (i.e. aggravated conditions for microbes

Current advancements and challenges in soil-root interactions modelling

NASA Astrophysics Data System (ADS)

Schnepf, Andrea; Huber, Katrin; Abesha, Betiglu; Meunier, Felicien; Leitner, Daniel; Roose, Tiina; Javaux, Mathieu; Vanderborght, Jan; Vereecken, Harry

2015-04-01

Roots change their surrounding soil chemically, physically and biologically. This includes changes in soil moisture and solute concentration, the exudation of organic substances into the rhizosphere, increased growth of soil microorganisms, or changes in soil structure. The fate of water and solutes in the root zone is highly determined by these root-soil interactions. Mathematical models of soil-root systems in combination with non-invasive techniques able to characterize root systems are a promising tool to understand and predict the behaviour of water and solutes in the root zone. With respect to different fields of applications, predictive mathematical models can contribute to the solution of optimal control problems in plant recourse efficiency. This may result in significant gains in productivity, efficiency and environmental sustainability in various land use activities. Major challenges include the coupling of model parameters of the relevant processes with the surrounding environment such as temperature, nutrient concentration or soil water content. A further challenge is the mathematical description of the different spatial and temporal scales involved. This includes in particular the branched structures formed by root systems or the external mycelium of mycorrhizal fungi. Here, reducing complexity as well as bridging between spatial scales is required. Furthermore, the combination of experimental and mathematical techniques may advance the field enormously. Here, the use of root system, soil and rhizosphere models is presented through a number of modelling case studies, including image based modelling of phosphate uptake by a root with hairs, model-based optimization of root architecture for phosphate uptake from soil, upscaling of rhizosphere models, modelling root growth in structured soil, and the effect of root hydraulic architecture on plant water uptake efficiency and drought resistance.

Current Advancements and Challenges in Soil-Root Interactions Modelling

NASA Astrophysics Data System (ADS)

Schnepf, A.; Huber, K.; Abesha, B.; Meunier, F.; Leitner, D.; Roose, T.; Javaux, M.; Vanderborght, J.; Vereecken, H.

2014-12-01

Roots change their surrounding soil chemically, physically and biologically. This includes changes in soil moisture and solute concentration, the exudation of organic substances into the rhizosphere, increased growth of soil microorganisms, or changes in soil structure. The fate of water and solutes in the root zone is highly determined by these root-soil interactions. Mathematical models of soil-root systems in combination with non-invasive techniques able to characterize root systems are a promising tool to understand and predict the behaviour of water and solutes in the root zone. With respect to different fields of applications, predictive mathematical models can contribute to the solution of optimal control problems in plant recourse efficiency. This may result in significant gains in productivity, efficiency and environmental sustainability in various land use activities. Major challenges include the coupling of model parameters of the relevant processes with the surrounding environment such as temperature, nutrient concentration or soil water content. A further challenge is the mathematical description of the different spatial and temporal scales involved. This includes in particular the branched structures formed by root systems or the external mycelium of mycorrhizal fungi. Here, reducing complexity as well as bridging between spatial scales is required. Furthermore, the combination of experimental and mathematical techniques may advance the field enormously. Here, the use of root system, soil and rhizosphere models is presented through a number of modelling case studies, including image based modelling of phosphate uptake by a root with hairs, model-based optimization of root architecture for phosphate uptake from soil, upscaling of rhizosphere models, modelling root growth in structured soil, and the effect of root hydraulic architecture on plant water uptake efficiency and drought resistance.

Soil Science Education for Primary and Secondary Students

NASA Astrophysics Data System (ADS)

Sparrow, Elena; Yoshikawa, Kenji; Kopplin, Martha

2013-04-01

Soils is one of the science investigation areas in the Global learning and Observations to Benefit the Environment (GLOBE), an international science and education program (112 countries) that teaches primary and secondary students to learn science by doing science. For each area of investigation GLOBE provides background information, measurement protocols and learning activities compiled as a chapter in the GLOBE Teacher's Guide. Also provided are data sheets and field guides to assist in the accurate collection of data as well as suggestions of scientific instruments and calibration methods. Teachers learn GLOBE scientific measurement protocols at professional development workshops led by scientists and educators, who then engage their students in soil studies that also contribute to ongoing science investigations. Students enter their data on the GLOBE website and can access their data as well as other data contributed by students from other parts of the world. Soil characterization measurements carried out in the field include site description, horizon depths, soil structure, soil color, soil consistence, soil texture, roots, rocks and carbonates. Other field measurements are soil temperature and soil moisture monitoring while the following measurements are carried out in the classroom or laboratory: gravimetric soil moisture, bulk density, particle density, particle size distribution, pH and soil fertility (nitrogen, phosphorus and potassium). Learning activities provide support for preparing students to do the measurements and for better understanding of science concepts. Many countries in GLOBE have adopted standards for education including science education with commonalities among them. For the Teacher's Guide, the National Science Education Standards published by the US National Academy of Sciences, selected additional content standards that GLOBE scientists and educators feel are appropriate and the National Geography Standards prepared by the (US

Measuring soil sustainability via soil resilience.

PubMed

Ludwig, Marie; Wilmes, Paul; Schrader, Stefan

2018-06-01

Soils are the nexus of water, energy and food, which illustrates the need for a holistic approach in sustainable soil management. The present study therefore aimed at identifying a bioindicator for the evaluation of soil management sustainability in a cross-disciplinary approach between soil science and multi-omics research. For this purpose we first discuss the remaining problems and challenges of evaluating sustainability and consequently suggest one measurable bioindicator for soil management sustainability. In this concept, we define soil sustainability as the maintenance of soil functional integrity. The potential to recover functional and structural integrity after a disturbance is generally defined as resilience. This potential is a product of the past and the present soil management, and at the same time prospect of possible soil responses to future disturbances. Additionally, it is correlated with the multiple soil functions and hence reflecting the multifunctionality of the soil system. Consequently, resilience can serve as a bioindicator for soil sustainability. The measurable part of soil resilience is the response diversity, calculated from the systematic contrasting of multi-omic markers for genetic potential and functional activity, and referred to as potential Maximum Ecological Performance (MEPpot) in this study. Calculating MEPpot will allow to determine the thresholds of resistance and resilience and potential tipping points for a regime shift towards irreversible or permanent unfavorable soil states for each individual soil considered. The calculation of such ecosystem thresholds is to our opinion the current global cross-disciplinary challenge. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

Hyperspectral Imaging Analysis for the Classification of Soil Types and the Determination of Soil Total Nitrogen

PubMed Central

Jia, Shengyao; Li, Hongyang; Wang, Yanjie; Tong, Renyuan; Li, Qing

2017-01-01

Soil is an important environment for crop growth. Quick and accurately access to soil nutrient content information is a prerequisite for scientific fertilization. In this work, hyperspectral imaging (HSI) technology was applied for the classification of soil types and the measurement of soil total nitrogen (TN) content. A total of 183 soil samples collected from Shangyu City (People’s Republic of China), were scanned by a near-infrared hyperspectral imaging system with a wavelength range of 874–1734 nm. The soil samples belonged to three major soil types typical of this area, including paddy soil, red soil and seashore saline soil. The successive projections algorithm (SPA) method was utilized to select effective wavelengths from the full spectrum. Pattern texture features (energy, contrast, homogeneity and entropy) were extracted from the gray-scale images at the effective wavelengths. The support vector machines (SVM) and partial least squares regression (PLSR) methods were used to establish classification and prediction models, respectively. The results showed that by using the combined data sets of effective wavelengths and texture features for modelling an optimal correct classification rate of 91.8%. could be achieved. The soil samples were first classified, then the local models were established for soil TN according to soil types, which achieved better prediction results than the general models. The overall results indicated that hyperspectral imaging technology could be used for soil type classification and soil TN determination, and data fusion combining spectral and image texture information showed advantages for the classification of soil types. PMID:28974005

[Effect of long-term fertilizing regime on soil microbial diversity and soil property].

PubMed

Li, Chenhua; Zhang, Caixia; Tang, Lisong; Xiong, Zhengqin; Wang, Baozhan; Jia, Zhongjun; Li, Yan

2014-03-04

To evaluate the effect of long-term fertilization on soil microbial community and soil chemical and physical properties. Using a high-throughput pyrosequencing technique, we studied microbial community in the 0-300 cm soil samples covering a 20-year field-experiment with different fertilization applications including inorganic fertilizer alone (N 300 kg/hm2, P2O5 150 kg/hm2 and K2O 60 kg/hm2) and inorganic fertilizer combined with straw (same application rate of N and P fertilizer combined with 5.4 t straw). Actinobacteria and alpha-proteobacteria were the predominant groups in the topsoil (0-20 cm). As the soil depth increased, the relative abundance of actinobacteria decreased whereas that of proteobacteria, especially gamma-proteobacteria and beta-proteobacteria increased and gradually became the dominant groups in the subsoil (20-300 cm). Long-term fertilizing applications significantly affected soil microbial communities throughout the soil profile, and increased the relative abundance of ammonia-oxidizing archaea at 0-40 cm depth. In addition, agriculture management, e. g. irrigation may be an important driving factor for the distribution of ammonia-oxidizing bacteria in soil profile. Total nitrogen and organic carbon contents were the most influential factors on microbial community in the topsoil and in the subsoil, respectively. Long-term fertilizer applications altered soil nutrient availability within the soil profile, which was likely to result in the different microbial community structure between the fertilizer treatments, especially for the subsoil.

A simple evaluation of soil quality of waterlogged purple paddy soils with different productivities.

PubMed

Liu, Zhanjun; Zhou, Wei; Lv, Jialong; He, Ping; Liang, Guoqing; Jin, Hui

2015-01-01

Evaluation of soil quality can be crucial for designing efficient farming systems and ensuring sustainable agriculture. The present study aimed at evaluating the quality of waterlogged purple paddy soils with different productivities in Sichuan Basin. The approach involved comprehensive analyses of soil physical and chemical properties, as well as enzyme activities and microbial community structure measured by phospholipid fatty acid analysis (PLFA). A total of 36 soil samples were collected from four typical locations, with 12 samples representing high productivity purple paddy soil (HPPS), medium productivity purple paddy soil (MPPS) and low productivity purple paddy soil (LPPS), respectively. Most measured soil properties showed significant differences (P ≤ 0.05) among HPPS, MPPS and LPPS. Pearson correlation analysis and principal component analysis were used to identify appropriate soil quality indicators. A minimum data set (MDS) including total nitrogen (TN), available phosphorus (AP), acid phosphatase (ACP), total bacteria (TB) and arbuscular mycorrhizal fungi was established and accounted for 82.1% of the quality variation among soils. A soil quality index (SQI) was developed based on the MDS method, whilst HPPS, MPPS and LPPS received mean SQI scores of 0.725, 0.536 and 0.425, respectively, with a ranking of HPPS > MPPS > LPPS. HPPS showed relatively good soil quality characterized by optimal nutrient availability, enzymatic and microbial activities, but the opposite was true of LPPS. Low levels of TN, AP and soil microbial activities were considered to be the major constraints limiting the productivity in LPPS. All soil samples collected were rich in available N, K, Si and Zn, but deficient in available P, which may be the major constraint for the studied regions. Managers in our study area should employ more appropriate management in the LPPS to improve its rice productivity, and particularly to any potential limiting factor.

Soil agroecosystem health: current challenges and future opportunities

USDA-ARS?s Scientific Manuscript database

Soil health is a broad concept that emphasizes the ecological importance of soils, including sustained plant and animal productivity, human health, and environmental quality. In the United States, soil degradation and associated water quality problems have been widely documented. Improvement and mai...

The influence of land-use and land-management on Soil Organic Carbon concentrations: Limitations of making predictions using only soil order data

NASA Astrophysics Data System (ADS)

Bell, M. J.; Worrall, F.

2009-04-01

In light of recent concern over the extent of global warming and the role of soil carbon as a potential store of atmospheric carbon, there is increasing demand for regions to estimate their current soil organic carbon (SOC) stocks with the greatest possible accuracy. Several previous attempts at calculating SOC baselines at global, national or regional scale have used mean values for soil orders and multiplied these values by the mapped areas of the soils they represent. Other methods have approached the task from a land cover point of view, making estimates using only land-use, or soil order/land-use combinations and others have included variables such as altitude, climate and soil texture. This study aimed to assess the major controls on SOC concentrations (%SOC) at the National Trust Wallington estate in Northumberland, NE England (area = 55km2) where an extensive soil sampling campaign was used to test what level of accuracy could be achieved in modelling the %SOC values on the Estate. Mapped %SOC values were compared to the values predicted from The National Soils Resources Institute (NSRI) representative soil profile data for major soil group, soil series and land-use corrected soil series values, as well as land-use/major soil group combinations from the Countryside Survey database. The results of this study can be summarised as follows: When only soil series or land-use were used as predictors only 48% and 44% of the variation in the dataset were explained. When soil series/land-use combinations were used explanatory power increased to 57% both altitude and soil pH are major controls on %SOC and including these variables gave an improvement to 59% A further improvement from 59% to 66% in the ability to predict %SOC levels at point locations when farm tenancy was included indicates that differences in land-management practices between farm tenancies explained more of the variation than either soil series or land-use in %SOC. Further work will involve a

Martian (and Cold Region Lunar) Soil Mechanics Considerations

NASA Astrophysics Data System (ADS)

Chua, Koon Meng; Johnson, Stewart W.

1998-01-01

The exploration of Mars has generated a lot of interest in recent years. With the completion of the Pathfinder Mission and the commencement of detailed mapping by Mars Global Surveyor, the possibility of an inhabited outpost on the planet is becoming more realistic. In spite of the upbeat mood, human exploration of Mars is still many years in the future. Additionally, the earliest return of any martian soil samples will probably not be until 2008. So why the discussion about martian soil mechanics when there are no returned soil samples on hand to examine? In view of the lack of samples, the basis of this or any discussion at this time must necessarily be one that involves conjecture, but not without the advantage of our knowledge of regolith mechanics of the Moon and soil mechanics on Earth. The objective of this presentation/discussion is fourfold: (1) Review some basic engineering-related information about Mars that may be of interest to engineers, and scientists - including characteristics of water and C02 at low temperature; (2) review and bring together principles of soil mechanics pertinent to studying and predicting how martian soil may behave, including the morphology and physical characteristics of coarse-grained and fine-grained soils (including clays), the characteristics of collapsing soils, potentials and factors that affect migration of water in unfrozen and freezing/frozen soils, and the strength and stiffness characteristics of soils at cold temperatures; (3) discuss some preliminary results of engineering experiments performed with frozen lunar soil simulants, JSC-1, in the laboratory that show the response to temperature change with and without water, effects of water on the strength and stiffness at ambient and at below freezing temperatures; and (4) discuss engineering studies that could be performed prior to human exploration and engineering research to be performed alongside future scientific missions to that planet.

Missouri Ozark forest soils: perspectives and realities

Treesearch

R. David. Hammer

1997-01-01

Ozark forest soils are dynamic in space and time, and most formed in multiple parent materials. Erosion and mass movement have been variable and extensive. Soil attributes including texture, cation exchange capacity, and mineralogy are related to geologic strata and to geomorphic conditions. Soil organic carbon content is influenced by surface shape, position in...

The World Soil Museum: education and advocacy on soils of the world

NASA Astrophysics Data System (ADS)

Mantel, Stephan; Land, Hiske

2013-04-01

The World Soil Museum (WSM) in Wageningen, is part of ISRIC World Soil Information and was founded in 1966 on request of the United Nations Educational, Scientific and Cultural Organization (UNESCO) and the International Soil Science Society. The World Soil Museum has a collection of over 1100 soil profiles from more than 70 countries. This soil profiles are vertical sections and show the composition, layering and structure of the soil. The collection is unique in the world and includes a significant number of soil profiles from the Netherlands. The Dutch soil collection is important for serving broader visitor groups, as some visitors, such as secondary school classes, are specifically interested in the Dutch landscape and soils. Broadly speaking, the World Soil Museum has five functions: (i) education and courses, (ii) research, (iii) information and edutainment, (iv) social function, and (v) a real museum function (Art). The World Soil Museum (World Soil Museum) is well known in national and international circles soil and the English name has almost 1,000 references on the Internet. The World Soil Museum is visited by about 1000 people a year, mainly university and college students from Western Europe. Other visitor groups that have found their way to the museum are students from disciplines broader then soil science, such as geography and rural development. Secondary school classes visit the museum for geography classes. The uniqueness and the value of the collection of soil profiles (soil monoliths) and associated collections, such as soil samples, hand pieces, thin sections, slides, is emphasized by the fact ISRIC is the only World Data Centre for Soils (WDC-Soils) within the World Data System of the International Council of Science (ICSU). The collection provides an insight in and overview of the diversity of soils in the world, their properties and their limitations and possibilities for use. A new building is under construction for the WSM, which is

Effects of Tillage Practices on Soil Organic Carbon and Soil Respiration

NASA Astrophysics Data System (ADS)

Rusu, Teodor; Ioana Moraru, Paula; Bogdan, Ileana; Ioan Pop, Adrian

2016-04-01

Soil tillage system and its intensity modify by direct and indirect action soil temperature, moisture, bulk density, porosity, penetration resistance and soil structural condition. Minimum tillage and no-tillage application reduce or completely eliminate the soil mobilization, due to this, soil is compacted in the first years of application. The degree of compaction is directly related to soil type and its state of degradation. All this physicochemical changes affect soil biology and soil respiration. Soil respiration leads to CO2 emissions from soil to the atmosphere, in significant amounts for the global carbon cycle. Soil respiration is one measure of biological activity and decomposition. Soil capacity to produce CO2 varies depending on soil, season, intensity and quality of agrotechnical tillage, soil water, cultivated plant and fertilizer. Our research follows the effects of the three tillage systems: conventional system, minimum tillage and no-tillage on soil respiration and finally on soil organic carbon on rotation soybean - wheat - maize, obtained on an Argic Faeoziom from the Somes Plateau, Romania. To quantify the change in soil respiration under different tillage practices, determinations were made for each crop in four vegetative stages (spring, 5-6 leaves, bean forming, harvest). Soil monitoring system of CO2 and O2 included gradient method, made by using a new generation of sensors capable of measuring CO2 concentration in-situ and quasi-instantaneous in gaseous phase. At surface soil respiration is made by using ACE Automated Soil CO2 Exchange System. These areas were was our research presents a medium multi annual temperature of 8.20C medium of multi annual rain drowns: 613 mm. The experimental variants chosen were: i). Conventional system: reversible plough (22-25 cm) + rotary grape (8-10 cm); ii). Minimum tillage system: paraplow (18-22 cm) + rotary grape (8-10 cm); iii). No-tillage. The experimental design was a split-plot design with three

Soil water repellency under stones, forest residue mulch and bare soil following wildfire.

NASA Astrophysics Data System (ADS)

Martins, Martinho A. S.; Prats, Sérgio A.; van Keulen, Daan; Vieira, Diana C. S.; Silva, Flávio C.; Keizer, Jan J.; Verheijen, Frank G. A.

2017-04-01

Soil water repellency (SWR) is a physical property that is commonly defined as the aptitude of soil to resist wetting. It has been documented for a wide range of soil and vegetation types, and can vary with soil organic matter (SOM) content and type, soil texture, soil moisture content (SMC) and soil temperature. Fire can induce, enhance or destroy SWR and, therefore, lead to considerable changes in soil water infiltration and storage and increase soil erosion by water, thereby weakening soil quality. In Portugal, wildfires occur frequently and affect large areas, on average some 100000 ha per year, but over 300000 ha in extreme years such as 2003 and 2005. This can have important implications in geomorphological and hydrological processes, as evidenced by the strong and sometimes extreme responses in post-fire runoff and erosion reported from various parts of the world, including Portugal. Thereby, the application of mulches from various materials to cover burned areas has been found to be an efficient stabilization treatment. However, little is known about possible side effects on SWR, especially long term effects. Forest SWR is very heterogeneous, as a result of variation in proximity to trees/shrubs, litter type and thickness, cracks, roots, and stones. This study targeted the spatial heterogeneity of soil water repellency under eucalypt plantation, five years after a wildfire and forest residue mulching application. The main objectives of this work were: 1) to assess the long-term effect of mulching application on the strength and spatial heterogeneity of topsoil SWR, by comparing SWR on bare soil, under stones, and under mulching remains; 2) to assess SWR at 1 cm depth between O and Ah horizons. The soil surface results showed that untreated bare soil areas were slightly more water repellent than mulched areas. However, under stones there were no SWR differences between mulched and control areas. At 1 cm depth, there was a marked mulching effect on SWR, even

Formulation of humic-based soil conditioners

NASA Astrophysics Data System (ADS)

Amanova, M. A.; Mamytova, G. A.; Mamytova, B. A.; Kydralieva, K. A.; Jorobekova, Sh. J.

2009-04-01

The goal of the study is to prepare soil conditioners (SC) able to carry out the following functions: (i) the chemical conditioning of soil mainly comprising the adjustment of pH, (ii) the balancing of inorganic nutrients, (iii) the physical conditioning of soil mainly comprising the improvement of water permeability, air permeability and water retention properties, and (iv) improvement of the ecological system concerning of useful microorganisms activity in the soil. The SC was made of a mixture of inorganic ingredients, a chemical composition and physical and chemical properties of which promoted improvement of physical characteristic of soil and enrichment by its mineral nutritious elements. In addition to aforesaid ingredients, this soil conditioner contains agronomical-valued groups of microorganisms having the function promoting the growth of the crop. As organic component of SC humic acids (HA) was used. HA serve many major functions that result in better soil and plant health. In soil, HA can increase microbial and mycorrhizal activity while enhancing nutrient uptake by plant roots. HA work as a catalyst by stimulating root and plant growth, it may enhance enzymatic activity that in turn accelerates cell division which can lead to increased yields. HA can help to increase crop yields, seed germination, and much more. In short, humic acids helps keep healthy plants health. The first stage goal was to evaluate mineral and organic ingredients for formulation of SC. Soil conditioners assessed included ash and slag. The use of slags has been largelly used in agriculture as a source of lime and phosphoric acid. The silicic acid of slags reduces Al-acitivity thus, promoting a better assimilation of P-fertilizer by plants. Additionally, silicic acid is also known to improve soil moisture capacity, thus enhancing soil water availability to plants. Physico-chemical characteristics of ash and slag were determined, as a total - about 20 samples. Results include

National Soil Information System in Turkey

NASA Astrophysics Data System (ADS)

Emrah Erdogan, Hakki; Sahin, Mehmet; Sahin, Yuksel

2013-04-01

Land consolidation (LC) represents complexity if management, legal, economic and technical procedures realized in order to adjust the land structure according to actual human preferences and needs. It includes changes in ownership rights to land and other real estate property, exchange of parcels among owners, changes in parcel borders, parcel size and shape, joining and dividing of parcels, changes in land use, construction works as roads, bridges, water changes etc.. Since the subject of LC is agricultural lands, the quality of consolidation depends on the quality of soil data. General Directorate of Agrarian Reform (GDAR) is the responsible institution on land consolidation whole of Turkey. Under GDAR, National Soil Information System (NSIS) has been build up with base soil data in relevant scale (1:5000). NSIS contain detailed information on soil chemical and physical properties, current land use, parent material, land capability class, Storie Index Values. SI were used on land consolidation, land use planning and farm development services. LCC was used for land distribution, rental land; define of village settlement, consolidation, expropriation, reconstruction, reclamation, non-agricultural usage. LCC were also specified to subclasses in four different limited factors as i) flow and erosion risk ii) requirement of drainage and soil moisture iii) Limits of soil tillage and root (shallow soils, low water retention capacity, stony, salty .etc) iv) climatic limits. In this study, digital soil survey and mapping project located in Yumurtalik, Adana is presented as an example of NSIS data structure. The project cover an area of 45709 ha that include crop lands as an area of 28528 ha and other land use (urban, roads..etc) as an area of 17181 ha. Soil profiles were described in 45 different points and totally 1279 soil samples were collected in field study and the check bore hole were made in 3170 points.

How soil organic matter composition controls hexachlorobenzene-soil-interactions: adsorption isotherms and quantum chemical modeling.

PubMed

Ahmed, Ashour A; Kühn, Oliver; Aziz, Saadullah G; Hilal, Rifaat H; Leinweber, Peter

2014-04-01

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 soilsoil+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 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 HCB adsorption. To obtain a molecular level understanding, a test set has been developed on the basis of elemental analysis which comprises 32 representative soil constituents. The calculated binding energy for HCB with each representative system shows that HCB binds to SOM stronger than to soil minerals. For SOM, HCB binds to alkylated aromatic, phenols, lignin monomers, and hydrophobic aliphatic compounds stronger than to polar aliphatic compounds confirming the above adsorption isotherms. Moreover, quantitative structure-activity relationship (QSAR) of the binding energy with independent physical properties of the test set systems for the first time indicated that the polarizability, the partial charge on the carbon atoms, and the molar volume are the most important properties controlling HCB-SOM interactions. Copyright © 2013 Elsevier B.V. All rights reserved.

Impact of monovalent cations on soil structure. Part II. Results of two Swiss soils

NASA Astrophysics Data System (ADS)

Farahani, Elham; Emami, Hojat; Keller, Thomas

2018-01-01

In this study, we investigated the impact of adding solutions with different potassium and sodium concentrations on dispersible clay, water retention characteristics, air permeability, and soil shrinkage behaviour using two agricultural soils from Switzerland with different clay content but similar organic carbon to clay ratio. Three different solutions (including only Na, only K, and the combination of both) were added to soil samples at three different cation ratio of soil structural stability levels, and the soil samples were incubated for one month. Our findings showed that the amount of readily dispersible clay increased with increasing Na concentrations and with increasing cation ratio of soil structural stability. The treatment with the maximum Na concentration resulted in the highest water retention and in the lowest shrinkage capacity. This was was associated with high amounts of readily dispersible clay. Air permeability generally increased during incubation due to moderate wetting and drying cycles, but the increase was negatively correlated with readily dispersible clay. Readily dispersible clay decreased with increasing K, while readily dispersible clay increased with increasing K in Iranian soil (Part I of our study). This can be attributed to the different clay mineralogy of the studied soils (muscovite in Part I and illite in Part II).

Root controls on soil microbial community structure in forest soils.

PubMed

Brant, Justin B; Myrold, David D; Sulzman, Elizabeth W

2006-07-01

We assessed microbial community composition as a function of altered above- and belowground inputs to soil in forest ecosystems of Oregon, Pennsylvania, and Hungary as part of a larger Detritus Input and Removal Treatment (DIRT) experiment. DIRT plots, which include root trenching, aboveground litter exclusion, and doubling of litter inputs, have been established in forested ecosystems in the US and Europe that vary with respect to dominant tree species, soil C content, N deposition rate, and soil type. This study used phospholipid fatty-acid (PLFA) analysis to examine changes in the soil microbial community size and composition in the mineral soil (0-10 cm) as a result of the DIRT treatments. At all sites, the PLFA profiles from the plots without roots were significantly different from all other treatments. PLFA analysis showed that the rootless plots generally contained larger quantities of actinomycete biomarkers and lower amounts of fungal biomarkers. At one of the sites in an old-growth coniferous forest, seasonal changes in PLFA profiles were also examined. Seasonal differences in soil microbial community composition were greater than treatment differences. Throughout the year, treatments without roots continued to have a different microbial community composition than the treatments with roots, although the specific PLFA biomarkers responsible for these differences varied by season. These data provide direct evidence that root C inputs exert a large control on microbial community composition in the three forested ecosystems studied.

Litter decay controlled by temperature, not soil properties, affecting future soil carbon.

PubMed

Gregorich, Edward G; Janzen, Henry; Ellert, Benjamin H; Helgason, Bobbi L; Qian, Budong; Zebarth, Bernie J; Angers, Denis A; Beyaert, Ronald P; Drury, Craig F; Duguid, Scott D; May, William E; McConkey, Brian G; Dyck, Miles F

2017-04-01

Widespread global changes, including rising atmospheric CO 2 concentrations, climate warming and loss of biodiversity, are predicted for this century; all of these will affect terrestrial ecosystem processes like plant litter decomposition. Conversely, increased plant litter decomposition can have potential carbon-cycle feedbacks on atmospheric CO 2 levels, climate warming and biodiversity. But predicting litter decomposition is difficult because of many interacting factors related to the chemical, physical and biological properties of soil, as well as to climate and agricultural management practices. We applied 13 C-labelled plant litter to soil at ten sites spanning a 3500-km transect across the agricultural regions of Canada and measured its decomposition over five years. Despite large differences in soil type and climatic conditions, we found that the kinetics of litter decomposition were similar once the effect of temperature had been removed, indicating no measurable effect of soil properties. A two-pool exponential decay model expressing undecomposed carbon simply as a function of thermal time accurately described kinetics of decomposition. (R 2  = 0.94; RMSE = 0.0508). Soil properties such as texture, cation exchange capacity, pH and moisture, although very different among sites, had minimal discernible influence on decomposition kinetics. Using this kinetic model under different climate change scenarios, we projected that the time required to decompose 50% of the litter (i.e. the labile fractions) would be reduced by 1-4 months, whereas time required to decompose 90% of the litter (including recalcitrant fractions) would be reduced by 1 year in cooler sites to as much as 2 years in warmer sites. These findings confirm quantitatively the sensitivity of litter decomposition to temperature increases and demonstrate how climate change may constrain future soil carbon storage, an effect apparently not influenced by soil properties. © 2016 Her Majesty

Use of satellite and modeled soil moisture data for predicting event soil loss at plot scale

NASA Astrophysics Data System (ADS)

Todisco, F.; Brocca, L.; Termite, L. F.; Wagner, W.

2015-09-01

The potential of coupling soil moisture and a Universal Soil Loss Equation-based (USLE-based) model for event soil loss estimation at plot scale is carefully investigated at the Masse area, in central Italy. The derived model, named Soil Moisture for Erosion (SM4E), is applied by considering the unavailability of in situ soil moisture measurements, by using the data predicted by a soil water balance model (SWBM) and derived from satellite sensors, i.e., the Advanced SCATterometer (ASCAT). The soil loss estimation accuracy is validated using in situ measurements in which event observations at plot scale are available for the period 2008-2013. The results showed that including soil moisture observations in the event rainfall-runoff erosivity factor of the USLE enhances the capability of the model to account for variations in event soil losses, the soil moisture being an effective alternative to the estimated runoff, in the prediction of the event soil loss at Masse. The agreement between observed and estimated soil losses (through SM4E) is fairly satisfactory with a determination coefficient (log-scale) equal to ~ 0.35 and a root mean square error (RMSE) of ~ 2.8 Mg ha-1. These results are particularly significant for the operational estimation of soil losses. Indeed, currently, soil moisture is a relatively simple measurement at the field scale and remote sensing data are also widely available on a global scale. Through satellite data, there is the potential of applying the SM4E model for large-scale monitoring and quantification of the soil erosion process.

Simple Laboratory Experiment for Illustrating Soil Respiration.

ERIC Educational Resources Information Center

Hattey, J. A.; Johnson, G. V.

1997-01-01

Describes an experiment to illustrate the effect of food source and added nutrients (N) on microbial activity in the soil. Supplies include air-dried soil, dried plant material, sources of carbon and nitrogen, a trap such as KOH, colored water, and a 500-mL Erlenmeyer flask. Includes a diagram of an incubation chamber to demonstrate microbial…

Soil Monitor: an advanced and freely accesible platform to challenge soil sealing in Italy

NASA Astrophysics Data System (ADS)

Langella, Giuliano; Basile, Angelo; Giannecchini, Simone; Domenico Moccia, Francesco; Munafò, Michele; Terribile, Fabio

2017-04-01

Soil sealing is known to be one of the most serious soil degradation processes since it greatly disturbs or removes essential ecosystem services. Although important policy documents (Roadmap to a Resource Efficient in Europe, SDG'S) promise to mitigate this problem, there are still no signs of change and today soil sealing continues to increase globally. We believe an immediate action is required to reduce the distance between the grand policy declarations and the poor availability of operational - and scientifically robust - tools to challenge soil sealing. These tools must be able to support the decisions made by people who manage and control the soil sealing, namely urban and landscape planning professionals and authorities. In this contribution, we demonstrate that soil sealing can be effectively challenged by the implementation of a dedicated Geospatial Cyberinfrastructure. The platform we are developing - named Soil Monitor - is at now a well-functioning prototype freely available at http://www.soilmonitor.it/. It has been developed by research scientists coming from different disciplines. The national authority for environmental protection (ISPRA) provided the dataset while INU (Italian association of urban planners) tested the soil sealing and the urban planning indicators. More generally, Soil Monitor has been designed to support the Italian policy documents connected to soil sealing: AS 1181, AS 2383, L. 22 May 2015, n. 68; L. 28 December, n. 221). Thus, it connects many different soil sealing aspects including science, community, policy and economy. Soil Monitor performs geospatial computation in real-time to support the decision making in the landscape planning. This aims at measuring soil sealing in order to mitigate it and in particular at recognizing actions to achieve the land degradation neutrality. The web platform covers the entire Italy, even though it is "Country-agnostic". Data are processed at a very high spatial resolution (10-20 m), which

A Soil Service Index: Peatland soils as a case study for quantifying the value, vulnerability, and status of soils

NASA Astrophysics Data System (ADS)

Loisel, J.; Harden, J. W.; Hugelius, G.

2017-12-01

What are the most important soil services valued by land stewards and planners? Which soil-data metrics can be used to quantify each soil service? What are the steps required to quantitatively index the baseline value of soil services and their vulnerability under different land-use and climate change scenarios? How do we simulate future soil service pathways (or trajectories) under changing management regimes using process-based ecosystem models? What is the potential cost (economic, social, and other) of soil degradation under these scenarios? How sensitive or resilient are soil services to prescribed management practices, and how does sensitivity vary over space and time? We are bringing together a group of scientists and conservation organizations to answer these questions by launching Soil Banker, an open and flexible tool to quantify soil services that can be used at any scale, and by any stakeholder. Our overarching goals are to develop metrics and indices to quantify peatland soil ecosystem services, monitor change of these services, and guide management. This paper describes our methodology applied to peatlands and presents two case studies (Indonesia and Patagonia) demonstrating how Peatland Soil Banker can be deployed as an accounting tool of peatland stocks, a quantitative measure of peatland health, and as a projection of peatland degradation or enhancement under different land-use cases. Why peatlands? They store about 600 billion tons of carbon that account for ⅓ of the world's soil carbon. Peatlands have dynamic GHG exchanges of CO2, CH4, and NOx with the atmosphere, which plays a role in regulating global climate; studies indicate that peatland degradation releases about 2-3 billion tons of CO2 to the atmosphere annually. These ecosystems also provide local and regional ecosystem services: they constitute important components of the N and P cycles, store about 10% of the world's freshwater and buffer large fluxes of freshwater on an annual basis

Associations between soil bacterial community structure and nutrient cycling functions in long-term organic farm soils following cover crop and organic fertilizer amendment.

PubMed

Fernandez, Adria L; Sheaffer, Craig C; Wyse, Donald L; Staley, Christopher; Gould, Trevor J; Sadowsky, Michael J

2016-10-01

Agricultural management practices can produce changes in soil microbial populations whose functions are crucial to crop production and may be detectable using high-throughput sequencing of bacterial 16S rRNA. To apply sequencing-derived bacterial community structure data to on-farm decision-making will require a better understanding of the complex associations between soil microbial community structure and soil function. Here 16S rRNA sequencing was used to profile soil bacterial communities following application of cover crops and organic fertilizer treatments in certified organic field cropping systems. Amendment treatments were hairy vetch (Vicia villosa), winter rye (Secale cereale), oilseed radish (Raphanus sativus), buckwheat (Fagopyrum esculentum), beef manure, pelleted poultry manure, Sustane(®) 8-2-4, and a no-amendment control. Enzyme activities, net N mineralization, soil respiration, and soil physicochemical properties including nutrient levels, organic matter (OM) and pH were measured. Relationships between these functional and physicochemical parameters and soil bacterial community structure were assessed using multivariate methods including redundancy analysis, discriminant analysis, and Bayesian inference. Several cover crops and fertilizers affected soil functions including N-acetyl-β-d-glucosaminidase and β-glucosidase activity. Effects, however, were not consistent across locations and sampling timepoints. Correlations were observed among functional parameters and relative abundances of individual bacterial families and phyla. Bayesian analysis inferred no directional relationships between functional activities, bacterial families, and physicochemical parameters. Soil functional profiles were more strongly predicted by location than by treatment, and differences were largely explained by soil physicochemical parameters. Composition of soil bacterial communities was predictive of soil functional profiles. Differences in soil function were

Soil Tillage Conservation and its Effect on Soil Properties Bioremediation and Sustained Production of Crops

NASA Astrophysics Data System (ADS)

Rusu, Teodor; Ioana Moraru, Paula; Muresan, Liliana; Andriuca, Valentina; Cojocaru, Olesea

2017-04-01

soil features resulted in a positive impact on the water permeability of the soil. Availability of soil moisture during the crop growth resulted in better plant water status. Subsequent release of conserved soil water regulated proper plant water status, soil structure, and lowered soil penetrometer resistance. Productions obtained at STC did not have significant differences for the wheat and maize crop but were higher for soybean. The advantages of minimum soil tillage systems for Romanian pedo-climatic conditions can be used to improve methods in low producing soils with reduced structural stability on sloped fields, as well as measures of water and soil conservation on the whole agroecosystem. Presently, it is necessary to make a change concerning the concept of conservation practices and to consider a new approach regarding the good agricultural practice. We need to focus on an upper level concerning conservation by focusing on soil quality. Carbon management is necessary for a complexity of matters including soil, water management, field productivity, biological fuel and climatic change. In conclusion a Sustainable Agriculture includes a range of complementary agricultural practices: (i) minimum soil tillage (through a system of reduced tillage or no-tillage) to preserve the structure, fauna and soil organic matter; (ii) permanent soil cover (cover crops, residues and mulches) to protect the soil and help to remove and control weeds; (iii) various combinations and rotations of the crops which stimulate the micro-organisms in the soil and controls pests, weeds and plant diseases. Acknowledgements: This paper was performed under the frame of the Partnership in priority domains - PNII, developed with the support of MEN-UEFISCDI, project no. PN-II-PT-PCCA-2013-4-0015: Expert System for Risk Monitoring in Agriculture and Adaptation of Conservative Agricultural Technologies to Climate Change, and International Cooperation Program - Sub-3.1. Bilateral AGROCEO c. no. 21BM

Approved Practices in Soil Conservation.

ERIC Educational Resources Information Center

Foster, Albert B.

This book is written for individuals who wish to apply conservation practices, especially those of soil and water conservation, without technical assistance, to meet one's own conditions, and within his own capability to apply them. To meet these needs, the book includes a discussion and description of soil and water conservation methods for the…

SITE EVALUATION OF SOIL AMENDMENT TECHNOLOGIES AT THE CROOKSVILLE/ROSEVILLE POTTERY AREA OF CONCERN - STAR ORGANICS SOIL RESCUE CAPSULE

EPA Science Inventory

This report briefly summarizes Star Organics treatment technology demonstration of a soil amendment process for lead contaminated soil at Roseville, OH. The evaluation included leaching, bioavailability, geotechnical, and geochemical testing methods.

Dynamics of the biological properties of soil and the nutrient release of Amorpha fruticosa L. litter in soil polluted by crude oil.

PubMed

Zhang, Xiaoxi; Liu, Zengwen; Luc, Nhu Trung; Liang, Xiao; Liu, Xiaobo

2015-11-01

Litter from Amorpha fruticosa, a potential phytoremediating plant, was collected and used in a decomposition experiment that involved the litterbag in soil polluted by crude oil. The dynamics of the biological properties of soil and the nutrient release of the litter were detected. The results indicated that (1) in lightly polluted soil (LP, petroleum concentration was 15 g kg(-1)), the bacteria (including actinomycetes), and fungi populations were significant higher than those in unpolluted soil (CK) at the 1st month after pollution, and the bacteria (including actinomycetes) populations were higher than those in the CK at the 6th and 12th months. In moderately polluted soil (MP, 30 g kg(-1)), the bacteria (including actinomycetes) populations were higher than those in the CK at the 1st and 6th months, whereas only the actinomycetes population was greater than that in the CK at the 12th month. In seriously polluted soil (SP, 45 g kg(-1)), only the fungi population was higher than that in the CK at the 6th month. (2) The activities of soil protease, carboxymethyl cellulase, and sucrase were generally inhibited in polluted soil. Peroxidase activity was generally inhibited in the LP and MP soil, and polyphenol oxidase activity was inhibited in the SP soil at 6-12 months. (3) At the end of litter decomposition, the LP soil significantly increased the release rate of all nutrients, except for K. The MP soil reduced the release rate of Fe and Mn, whereas it increased that of C and Cu. The SP soil decreased the release rate of all nutrients except for Cu and Zn. In conclusion, SP by crude oil would lead to limitations in the release of nutrients from the litter and to decreases in the community stability of a phytoremediating plant. A. fruticosa could only be used in phytoremediation of polluted soil at concentrations below 45 g kg(-1) (crude).

Land surface hydrology parameterization for atmospheric general circulation models including subgrid scale spatial variability

NASA Technical Reports Server (NTRS)

Entekhabi, D.; Eagleson, P. S.

1989-01-01

Parameterizations are developed for the representation of subgrid hydrologic processes in atmospheric general circulation models. Reasonable a priori probability density functions of the spatial variability of soil moisture and of precipitation are introduced. These are used in conjunction with the deterministic equations describing basic soil moisture physics to derive expressions for the hydrologic processes that include subgrid scale variation in parameters. The major model sensitivities to soil type and to climatic forcing are explored.

Climate change and predicting soil loss from rainfall

NASA Astrophysics Data System (ADS)

Kinnell, Peter

2017-04-01

Conceptually, rainfall has a certain capacity to cause soil loss from an eroding area while soil surfaces have a certain resistance to being eroded by rainfall. The terms "rainfall erosivity' and "soil erodibility" are frequently used to encapsulate the concept and in the Revised Universal Soil Loss Equation (RUSLE), the most widely used soil loss prediction equation in the world, average annual values of the R "erosivity" factor and the K "erodibility" factor provide a basis for accounting for variation in rainfall erosion associated with geographic variations of climate and soils. In many applications of RUSLE, R and K are considered to be independent but in reality they are not. In RUSLE2, provision has been made to take account of the fact that K values determined using soil physical factors have to be adjusted for variations in climate because runoff is not directly included as a factor in determining R. Also, the USLE event erosivity index EI30 is better related to accounting for event sediment concentration than event soil loss. While the USLE-M, a modification of the USLE which includes runoff as a factor in determining the event erosivity index provides better estimates of event soil loss when event runoff is known, runoff prediction provides a challenge to modelling event soil loss as climate changes

Latin Hypercube Sampling (LHS) at variable resolutions for enhanced watershed scale Soil Sampling and Digital Soil Mapping.

NASA Astrophysics Data System (ADS)

Hamalainen, Sampsa; Geng, Xiaoyuan; He, Juanxia

2017-04-01

Latin Hypercube Sampling (LHS) at variable resolutions for enhanced watershed scale Soil Sampling and Digital Soil Mapping. Sampsa Hamalainen, Xiaoyuan Geng, and Juanxia, He. AAFC - Agriculture and Agr-Food Canada, Ottawa, Canada. The Latin Hypercube Sampling (LHS) approach to assist with Digital Soil Mapping has been developed for some time now, however the purpose of this work was to complement LHS with use of multiple spatial resolutions of covariate datasets and variability in the range of sampling points produced. This allowed for specific sets of LHS points to be produced to fulfil the needs of various partners from multiple projects working in the Ontario and Prince Edward Island provinces of Canada. Secondary soil and environmental attributes are critical inputs that are required in the development of sampling points by LHS. These include a required Digital Elevation Model (DEM) and subsequent covariate datasets produced as a result of a Digital Terrain Analysis performed on the DEM. These additional covariates often include but are not limited to Topographic Wetness Index (TWI), Length-Slope (LS) Factor, and Slope which are continuous data. The range of specific points created in LHS included 50 - 200 depending on the size of the watershed and more importantly the number of soil types found within. The spatial resolution of covariates included within the work ranged from 5 - 30 m. The iterations within the LHS sampling were run at an optimal level so the LHS model provided a good spatial representation of the environmental attributes within the watershed. Also, additional covariates were included in the Latin Hypercube Sampling approach which is categorical in nature such as external Surficial Geology data. Some initial results of the work include using a 1000 iteration variable within the LHS model. 1000 iterations was consistently a reasonable value used to produce sampling points that provided a good spatial representation of the environmental

Application of soil quality indices to assess the status of agricultural soils irrigated with treated wastewaters

NASA Astrophysics Data System (ADS)

Morugán-Coronado, A.; Arcenegui, V.; García-Orenes, F.; Mataix-Solera, J.; Mataix-Beneyto, J.

2012-12-01

The supply of water is limited in some parts of the Mediterranean region, such as southeastern Spain. The use of treated wastewater for the irrigation of agricultural soils is an alternative to using better-quality water, especially in semi-arid regions. On the other hand, this practice can modify some soil properties, change their relationships, the equilibrium reached and influence soil quality. In this work two soil quality indices were used to evaluate the effects of irrigation with treated wastewater in soils. The indices were developed studying different soil properties in undisturbed soils in SE Spain, and the relationships between soil parameters were established using multiple linear regressions. This study was carried out in three areas of Alicante Province (SE Spain) irrigated with wastewater, including four study sites. The results showed slight changes in some soil properties as a consequence of irrigation with wastewater, the obtained levels not being dangerous for agricultural soils, and in some cases they could be considered as positive from an agronomical point of view. In one of the study sites, and as a consequence of the low quality wastewater used, a relevant increase in soil organic matter content was observed, as well as modifications in most of the soil properties. The application of soil quality indices indicated that all the soils of study sites are in a state of disequilibrium regarding the relationships between properties independent of the type of water used. However, there were no relevant differences in the soil quality indices between soils irrigated with wastewater with respect to their control sites for all except one of the sites, which corresponds to the site where low quality wastewater was used.

Animating the biodynamics of soil thickness using process vector analysis: A dynamic denudation approach to soil formation

USGS Publications Warehouse

Johnson, D.L.; Domier, J.E.J.; Johnson, D.N.

2005-01-01

This paper expands the dynamic denudation framework of landscape evolution by providing new process insights and details on how soil and its signature morphological feature, the biomantle, form and function in the environment. We examine soils and their biomantles from disparate parts of the world, from the tropics through midlatitudes and hyperarid through perhumid, a range that exhibits varying environments for, and of, life. We then explicate the process pathways that cause soils to thicken and thin, and to even disappear, then reform. We do this by examining thickness relationships, where soil thickness stand biomantle thickness bt are functions of upbuilding u and deepening d minus removal r processes, hence st/bt=f(u+d-r). Upbuilding has two subsets, u1, which includes all exogenous (allochthonous-outside) mineral and/or organic inputs to the soil system, and u2, which includes all endogenous (autochthonous-in situ) processes and productions, including weathering. Exogenous u1 inputs include eolian and slopewash inputs (sedimentations) of mineral and organic materials, mass wasting accumulations and the like. Endogenous u2 processes and productions include the sum of in situ bioturbations, biosynthetic productions, organic accumulations, biovoid productions, weathering and volume increases caused by their sum. Endogenous upbuildings, which dominantly occur in the biomantle, are basically biodynamic bd processes and productions, hence u2=bd. Therefore, if exogenous upbuildings u1 are minimal or zero, then biomantle thickness bt is expressed by bt=f(u2-r) or bt=f(bd-r). Drawing on these relationships, we employ a graphic-conceptual device called process vector analysis in a digital animation (see supplementary materials or cf. https://netfiles.uiuc.edu/jdomier/www/temp/ biomantle.html) that illustrates the main pathways that form both Earth's soil and its unique epidermis, the biomantle. We then discuss the main elements of the animation using still frames that

Soil management practices under organic farming

NASA Astrophysics Data System (ADS)

Aly, Adel; Chami Ziad, Al; Hamdy, Atef

2015-04-01

Organic farming methods combine scientific knowledge of ecology and modern technology with traditional farming practices based on naturally occurring biological processes. Soil building practices such as crop rotations, intercropping, symbiotic associations, cover crops, organic fertilizers and minimum tillage are central to organic practices. Those practices encourage soil formation and structure and creating more stable systems. In farm nutrient and energy cycling is increased and the retentive abilities of the soil for nutrients and water are enhanced. Such management techniques also play an important role in soil erosion control. The length of time that the soil is exposed to erosive forces is decreased, soil biodiversity is increased, and nutrient losses are reduced, helping to maintain and enhance soil productivity. Organic farming as systematized and certifiable approach for agriculture, there is no surprise that it faces some challenges among both farmers and public sector. This can be clearly demonstrated particularly in the absence of the essential conditions needed to implement successfully the soil management practices like green manure and composting to improve soil fertility including crop rotation, cover cropping and reduced tillage. Those issues beside others will be fully discussed highlighting their beneficial impact on the environmental soil characteristics. Keywords: soil fertility, organic matter, plant nutrition

Microbial ecology and biogeochemistry of continental Antarctic soils.

PubMed

Cowan, Don A; Makhalanyane, Thulani P; Dennis, Paul G; Hopkins, David W

2014-01-01

The Antarctica Dry Valleys are regarded as the coldest hyperarid desert system on Earth. While a wide variety of environmental stressors including very low minimum temperatures, frequent freeze-thaw cycles and low water availability impose severe limitations to life, suitable niches for abundant microbial colonization exist. Antarctic desert soils contain much higher levels of microbial diversity than previously thought. Edaphic niches, including cryptic and refuge habitats, microbial mats and permafrost soils all harbor microbial communities which drive key biogeochemical cycling processes. For example, lithobionts (hypoliths and endoliths) possess a genetic capacity for nitrogen and carbon cycling, polymer degradation, and other system processes. Nitrogen fixation rates of hypoliths, as assessed through acetylene reduction assays, suggest that these communities are a significant input source for nitrogen into these oligotrophic soils. Here we review aspects of microbial diversity in Antarctic soils with an emphasis on functionality and capacity. We assess current knowledge regarding adaptations to Antarctic soil environments and highlight the current threats to Antarctic desert soil communities.

Clay minerals, metallic oxides and oxy-hydroxides and soil organic carbon distribution within soil aggregates in temperate forest soils

NASA Astrophysics Data System (ADS)

Gartzia-Bengoetxea, Nahia; Fernández-Ugalde, Oihane; Virto, Iñigo; Arias-González, Ander

2017-04-01

trachytes (8.2%) with no significant differences between the last two. On the other hand, ditionithe extractable iron was significantly different among all soils with the following content: sandstone (13%) < trachytes (23%) < basalts (27%). Short-range order inorganic phases of Al and Fe were significantly higher in soils developed on volcanic parent materials. The distribution of organic C in soil aggregates revealed that as much as 50% of the organic C was concentrated in mega (20-10 mm and 10-5 mm) and large-(5-2 mm) aggregates in soils developed in sandstones, while 25% and 36% of the total organic C was found in theses aggregates in basaltic and trachytic soils respectively. Basaltic soils showed significantly higher proportion of organic C (>20%) in microaggregates (0.25-0.053 mm) and silt+clay size aggregates (< 0.053 mm) than the other two soils (<10%). The regression analysis revealed that short-range order minerals influence the amount of SOC via microaggregation and that chlorite-vermiculite mixed layer minerals had a significant influence on the amount of SOC relating this stabilization mechanism to macroagregation. This study highlights that dynamic models of SOC turnover in acid soils from temperate forest should include proxies for clay mineralogy and for the content of Fe and Al oxides and oxy-hydro-oxides.

Modelling the sensitivity of soil mercury storage to climate-induced changes in soil carbon pools

NASA Astrophysics Data System (ADS)

Hararuk, O.; Obrist, D.; Luo, Y.

2013-04-01

Substantial amounts of mercury (Hg) in the terrestrial environment reside in soils and are associated with soil organic carbon (C) pools, where they accumulated due to increased atmospheric deposition resulting from anthropogenic activities. The purpose of this study was to examine potential sensitivity of surface soil Hg pools to global change variables, particularly affected by predicted changes in soil C pools, in the contiguous US. To investigate, we included a soil Hg component in the Community Land Model based on empirical statistical relationships between soil Hg / C ratios and precipitation, latitude, and clay; and subsequently explored the sensitivity of soil C and soil Hg densities (i.e., areal-mass) to climate scenarios in which we altered annual precipitation, carbon dioxide (CO2) concentrations and temperature. Our model simulations showed that current sequestration of Hg in the contiguous US accounted for 15 230 metric tons of Hg in the top 0-40 cm of soils, or for over 300 000 metric tons when extrapolated globally. In the simulations, US soil Hg pools were most sensitive to changes in precipitation because of strong effects on soil C pools, plus a direct effect of precipitation on soil Hg / C ratios. Soil Hg pools were predicted to increase beyond present-day values following an increase in precipitation amounts and decrease following a reduction in precipitation. We found pronounced regional differences in sensitivity of soil Hg to precipitation, which were particularly high along high-precipitation areas along the West and East Coasts. Modelled increases in CO2 concentrations to 700 ppm stimulated soil C and Hg accrual, while increased air temperatures had small negative effects on soil C and Hg densities. The combined effects of increased CO2, increased temperature and increased or decreased precipitation were strongly governed by precipitation and CO2 showing pronounced regional patterns. Based on these results, we conclude that the combination

Use of satellite and modelled soil moisture data for predicting event soil loss at plot scale

NASA Astrophysics Data System (ADS)

Todisco, F.; Brocca, L.; Termite, L. F.; Wagner, W.

2015-03-01

The potential of coupling soil moisture and a~USLE-based model for event soil loss estimation at plot scale is carefully investigated at the Masse area, in Central Italy. The derived model, named Soil Moisture for Erosion (SM4E), is applied by considering the unavailability of in situ soil moisture measurements, by using the data predicted by a soil water balance model (SWBM) and derived from satellite sensors, i.e. the Advanced SCATterometer (ASCAT). The soil loss estimation accuracy is validated using in situ measurements in which event observations at plot scale are available for the period 2008-2013. The results showed that including soil moisture observations in the event rainfall-runoff erosivity factor of the RUSLE/USLE, enhances the capability of the model to account for variations in event soil losses, being the soil moisture an effective alternative to the estimated runoff, in the prediction of the event soil loss at Masse. The agreement between observed and estimated soil losses (through SM4E) is fairly satisfactory with a determination coefficient (log-scale) equal to of ~ 0.35 and a root-mean-square error (RMSE) of ~ 2.8 Mg ha-1. These results are particularly significant for the operational estimation of soil losses. Indeed, currently, soil moisture is a relatively simple measurement at the field scale and remote sensing data are also widely available on a global scale. Through satellite data, there is the potential of applying the SM4E model for large-scale monitoring and quantification of the soil erosion process.

The Metaproteome of "Park Grass" soil - a reference for EU soil science

NASA Astrophysics Data System (ADS)

Quinn, Gerry; Dudley, Ed; Doerr, Stefan; Matthews, Peter; Halen, Ingrid; Walley, Richard; Ashton, Rhys; Delmont, Tom; Francis, Lewis; Gazze, Salvatore Andrea; Van Keulen, Geertje

2016-04-01

Soil metaproteomics, the systemic extraction and identification of proteins from a soil, is key to understanding the biological and physical processes that occur within the soil at a molecular level. Until recently, direct extraction of proteins from complex soils have yielded only dozens of protein identifications due to interfering substances, such as humic acids and clay, which co-extract and/or strongly adsorb protein, often causing problems in downstream processing, e.g. mass spectrometry. Furthermore, the current most successful, direct, proteomic extraction protocol favours larger molecular weight and/or heat-stable proteins due to its extraction protocol. We have now developed a novel, faster, direct soil protein extraction protocol which also addressed the problem of interfering substances, while only requiring less than 1 gram of material per extraction. We extracted protein from the 'Genomic Observatory' Park Grass at Rothamsted Research (UK), an ideally suited geographic site as it is the longest (>150 years) continually studied experiment on ungrazed permanent grassland in the world, for which a rich history of environmental/ecological data has been collected, including high quality publically available metagenome DNA sequences. Using this improved methodology, in conjunction with the creation of high quality, curated metagenomic sequence databases, we have been able to significantly improve protein identifications from one soil due to extracting a similar number of proteins that were >90% different when compared to the best current direct protocol. This optimised metaproteomics protocol has now enabled identification of thousands of proteins from one soil, leading therefore to a deeper insight of soil system processes at the molecular scale.

Bioremediation of oil-contaminated soils by composting

NASA Astrophysics Data System (ADS)

Golodyaev, G. P.; Kostenkov, N. M.; Oznobikhin, V. I.

2009-08-01

Composting oil-contaminated soils under field conditions with the simultaneous optimization of their physicochemical and agrochemical parameters revealed the high efficiency of the soil purification, including that from benz[a]pyrene. The application of fertilizers and lime favored the intense development of indigenous microcenoses and the effective destruction of the oil. During the 95-day experimental period, the average daily rate of the oil decomposition was 157 mg/kg of soil. After the completion of the process, the soil became ecologically pure.

Soil Health Assessment Approaches and the Cornell Framework

NASA Astrophysics Data System (ADS)

van Es, Harold

2016-04-01

Soil health constraints beyond nutrient limitations and excesses currently limit agroecosystem productivity and sustainability, resilience to drought and extreme rainfall, and progress in soil and water conservation. With mounting pressure to produce food, feed, fiber, and even fuel for an increasing population, the concept of soil health is gaining national and international attention. Multiple regional, national, and global efforts are now leveraging that work to reach new stakeholder audiences, so that soil health management is expanding into mainstream agriculture. Each grower is generally faced with a unique situation in the choice of management options to address soil health constraints and each system affords its own set of opportunities or limitations to soil management. A more comprehensive understanding of soil health status can better guide farmers' management decisions. Until recently, there has not been a formalized decision making process for implementing a soil health management system that alleviates field-specific constrains identified through standard measurements and then maintains improved soil health. This presentation will discuss current US-based efforts related to soil health assessment, including efforts to build national consensus on appropriate methods for simple (inexpensive) and comprehensive tests. This includes the Cornell Soil Health Management Planning and Implementation Framework. The most relevant components of the framework are 1) measurement of indicators that represent critical soil processes, 2) scoring of measured values that allows for interpretation, and 3) linkage of identified constraints with management practices. Land managers can monitor changes over time through further assessment, and adapt management practices to achieve chosen goals. We will discuss the full tests and approaches for simplification.

Visualizing Soil Landscapes on Mobile Devices

NASA Astrophysics Data System (ADS)

Schulze, Darrell; Lindbo, David

2016-04-01

The Integrating Spatial Educational Experiences (Isee) project utilizes the most detailed US soil survey data to create thematic maps of soil properties that are then combined with a highly optimized hillshade basemap for display. The Isee app, currently available for the iPad platform from the Apple App Store, allows the cached maps to be zoomed and panned quickly to any location down to a scale of 1:18,000. Maps currently available for the states of Indiana, Illinois, Kentucky, Ohio, Texas, West Virginia, and Wisconsin include, Dominant Soil Parent Materials, Natural Soil Drainage Classes, Limiting Layers, Surface Soil Colors, and Acid Subsoils. Other thematic maps will be added in the future. The ability to zoom, pan, and change maps quickly allows the user to see and understand soil landscape relationships that are not often apparent using static maps, while the ability to access the maps conveniently in the field allows the user to see how soil landscape features on the maps appear in the field.

REMEDIATION OF SOILS CONTAMINATED WITH WOOD-TREATMENT CHEMICALS (PCP AND CREOSOTE)

EPA Science Inventory

PCP and creosote PAHs are found in most of the contaminated soils at wood-treatment sites. The treatment methods currently being used for such soils include soil washing, incineration, and biotreatment. Soil washing involves removal of the hazardous chemicals from soils ...

Soil fauna, soil properties and geo-ecosystem functioning

NASA Astrophysics Data System (ADS)

Cammeraat, L. H.

2012-04-01

The impact of soil fauna on soil processes is of utmost importance, as the activity of soil fauna directly affects soil quality. This is expressed by the direct effects of soil fauna on soil physical and soil chemical properties that not only have great importance to food production and ecosystems services, but also on weathering and hydrological and geomorphological processes. Soil animals can be perceived as ecosystem engineers that directly affect the flow of water, sediments and nutrients through terrestrial ecosystems. The biodiversity of animals living in the soil is huge and shows a huge range in size, functions and effects. Most work has been focused on only a few species such as earthworms and termites, but in general the knowledge on the effect of soil biota on soil ecosystem functioning is limited as it is for their impact on processes in the soil and on the soil surface. In this presentation we would like to review some of the impacts of soil fauna on soil properties that have implications for geo-ecosystem functioning and soil formation processes.

Invasive soil organisms and their effects on belowground processes

Treesearch

Erik Lilleskov; Jr. Mac A. Callaham; Richard Pouyat; Jane E. Smith; Michael Castellano; Grizelle Gonzalez; D. Jean Lodge; Rachel Arango; Frederick Green

2010-01-01

Invasive species have a wide range of effects on soils and their inhabitants. By altering soils, through their direct effects on native soil organisms (including plants), and by their interaction with the aboveground environment, invasive soil organisms can have dramatic effects on the environment, the economy and human health. The most widely recognized effects...

Towards a methodology for removing and reconstructing soil protists with intact soil microbial communities

NASA Astrophysics Data System (ADS)

Hu, Junwei; Tsegaye Gebremikael, Mesfin; Salehi Hosseini, Pezhman; De Neve, Stefaan

2017-04-01

Soil ecological theories on the role of soil fauna groups in soil functions are often tested in highly artificial conditions, i.e. on completely sterilized soils or pure quartz sand re-inoculated with a small selection of these fauna groups. Due to the variable sensitivity of different soil biota groups to gamma irradiation, the precise doses that can be administered, and the relatively small disturbance of soil physical and chemical properties (relative to e.g. autoclaving, freezing-thawing and chemical agents), gamma irradiation has been employed to selectively eliminate soil organisms. In recent research we managed to realistically estimate on the contribution of the entire nematode communities to C and N mineralization in soil, by selective removal of nematodes at 5 kGy gamma irradiation doses followed by reinoculation. However, we did not assess the population dynamics of protozoa in response to this irradiation, i.e. we could not assess the potential contribution of protists to the mineralization process. Selective removal of protists from soils with minimal disturbance of the soil microflora has never been attempted and constitutes a highly challenging but potentially groundbreaking technique in soil ecology. Accordingly, the objective of this research is to modify the successful methodology of selective elimination of nematodes, to selectively eliminate soil fauna including nematodes and protists with minimal effects on the soil microbial community and reconstruct soil protists and microbial communities in completely sterilized soil. To this end, we here compared two different approaches: 1) remove nematodes and protists while keeping the microbial community intact (through optimizing gamma irradiation doses); 2) reconstruct protists and microbial communities in sterilized soil (through adding multicellular fauna free pulverized soil). The experiment consists of 7 treatments with soil collected from 0 to 15 cm layer of an organically managed agricultural

A conceptual configuration of the lunar base bioregenerative life support system including soil-like substrate for growing plants

NASA Astrophysics Data System (ADS)

Liu, H.; Yu, C. Y.; Manukovsky, N. S.; Kovalev, V. S.; Gurevich, Yu L.; Wang, J.

2008-09-01

The paper presents a conceptual configuration of the lunar base bioregenerative life support system (LBLSS), including soil-like substrate (SLS) for growing plants. SLS makes it possible to combine the processes of plant growth and the utilization of plant waste. Plants are to be grown on SLS on the basis of 20 kg of dry SLS mass or 100 kg of wet SLS mass per square meter. The substrate is to be delivered to the base ready-made as part of the plant growth subsystem. Food for the crew was provided by prestored stock 24% and by plant growing system 76%. Total dry weight of the food is 631 g per day (2800 kcal/day) for one crew member (CM). The list of candidate plants to be grown under lunar BLSS conditions included 14 species: wheat, rice, soybean, peanuts, sweet pepper, carrots, tomatoes, coriander, cole, lettuce, radish, squash, onion and garlic. From the prestored stock the crew consumed canned fish, iodinated salt, sugar, beef sauce and seafood sauce. Our calculations show that to provide one CM with plant food requires the area of 47.5 m 2. The balance of substance is achieved by the removal dehydrated urine 59 g, feces 31 g, food waste 50 g, SLS 134 g, and also waters 86 g from system and introduction food 236 g, liquid potassium soap 4 g and mineral salts 120 g into system daily. To reduce system setup time the first plants could be sowed and germinated to a certain age on the Earth.

BOREAS TGB-12 Soil Carbon Data over the NSA

NASA Technical Reports Server (NTRS)

Trumbore, Susan; Hall, Forrest G. (Editor); Conrad, Sara K. (Editor); Harden, Jennifer; Sundquist, Eric; Winston, Greg

2000-01-01

The BOREAS TGB-12 team made measurements of soil carbon inventories, carbon concentration in soil gases, and rates of soil respiration at several sites to estimate the rates of carbon accumulation and turnover in each of the major vegetation types. TGB-12 data sets include soil properties at tower and selected auxiliary sites in the BOREAS NSA and data on the seasonal variations in the radiocarbon content of CO2 in the soil atmosphere at NSA tower sites. The sampling strategies for soils were designed to take advantage of local fire chronosequences, so that the accumulation of C in areas of moss regrowth could be determined. These data are used to calculate the inventory of C and N in moss and mineral soil layers at NSA sites and to determine the rates of input and turnover (using both accumulation since the last stand-killing fire and radiocarbon data). This data set includes physical parameters needed to determine carbon and nitrogen inventory in soils. The data were collected discontinuously from August 1993 to July 1996. The data are stored in tabular ASCII files.

A disconnect between O horizon and mineral soil carbon - Implications for soil C sequestration

NASA Astrophysics Data System (ADS)

Garten, Charles T., Jr.

2009-03-01

Changing inputs of carbon to soil is one means of potentially increasing carbon sequestration in soils for the purpose of mitigating projected increases in atmospheric CO 2 concentrations. The effect of manipulations of aboveground carbon input on soil carbon storage was tested in a temperate, deciduous forest in east Tennessee, USA. A 4.5-year experiment included exclusion of aboveground litterfall and supplemental litter additions (three times ambient) in an upland and a valley that differed in soil nitrogen availability. The estimated decomposition rate of the carbon stock in the O horizon was greater in the valley than in the upland due to higher litter quality (i.e., lower C/N ratios). Short-term litter exclusion or addition had no effect on carbon stock in the mineral soil, measured to a depth of 30 cm, or the partitioning of carbon in the mineral soil between particulate- and mineral-associated organic matter. A two-compartment model was used to interpret results from the field experiments. Field data and a sensitivity analysis of the model were consistent with little carbon transfer between the O horizon and the mineral soil. Increasing aboveground carbon input does not appear to be an effective means of promoting carbon sequestration in forest soil at the location of the present study because a disconnect exists in carbon dynamics between O horizon and mineral soil. Factors that directly increase inputs to belowground soil carbon, via roots, or reduce decomposition rates of organic matter are more likely to benefit efforts to increase carbon sequestration in forests where carbon dynamics in the O horizon are uncoupled from the mineral soil.

Temporal pattern of soil matric suction in the unsaturated soil slope under different forest cover

NASA Astrophysics Data System (ADS)

Hayati, Elyas; Abdi, Ehsan; Mohseni Saravi, Mohsen; Nieber, John; Majnounian, Baris; Chirico, Giovanni

2017-04-01

In the vadose zone, usually, soils experience high matric suction during dry periods which results in a significant additional soil strength component (i.e., apparent cohesion) and thus plays a crucial role in the stability of unsaturated soil slopes. But, in the wet periods, when rain-water infiltrates into the soil, the matric suction of the soil dissipates partially or completely. It is a well-understood concept that vegetation can modify the hillslope hydrology and subsequent stability conditions by increasing soil matric suction through both interception of rainfall and depletion of soil water content via transpiration. Anthropogenic pressures, particularly clear-cutting and deforestation, affect many hydro-geomorphological processes including catchment and hillslope hydrology and stability. However, quantifying the changes in soil hydrologic conditions and the resulted stability of slopes due to these degrading activities remained an unresolved problem. To address this gap, a continuous measurement of soil water dynamics has been conducted at two adjacent hillslopes (one forested hillslope and one degraded hillslope) using PR2/6 profile probe for a 9-month period of time to demonstrate the forest cover-specific influence on the hillslope hydrology and stability during different seasons. The results have been then presented in terms of estimated soil matric suction to facilitate analyzing the resulted stability states due to the changes in soil water balance with time in the two studied hillslopes. The data were tested to check whether there are any differences between the forested and degraded hillslopes in terms of soil matric suction and augmented soil cohesion during different seasons. Finally, the response of soil hydrologic condition and the resulted slope stability for the 9-month period were analyzed and discussed for the different hillslopes.

Soil Organic Chemistry.

ERIC Educational Resources Information Center

Anderson, G.

1979-01-01

A brief review is presented of some of the organic compounds and reactions that occur in soil. Included are nitrogenous compounds, compounds of phosphorus and sulfur, carbohydrates, phenolic compounds, and aliphatic acids. (BB)

Influence of carbon source amendment on effectiveness of anaerobic soil disinfestation

USDA-ARS?s Scientific Manuscript database

Anaerobic soil disinfestation (ASD; also termed biological soil disinfestation or soil reductive sterilization) is a non-chemical soil disinfestation process which includes 1) soil incorporation of a labile carbon (C) source, 2) mulching with a polyethylene film to limit gas exchange, and 3) drip ir...

Creating deep soil core monoliths: Beyond the solum

USDA-ARS?s Scientific Manuscript database

Soil monoliths serve as useful teaching aids in the study of the Earth’s critical zone where rock, soil, water, air, and organisms interact. Typical monolith preparation has so far been confined to the 1 to 2-m depth of the solum. Critical ecosystem services provided by soils include materials from ...

A Brief History of Soils and Human Health Studies

NASA Astrophysics Data System (ADS)

Brevik, Eric C.; Sauer, Thomas J.

2013-04-01

The idea that there are links between soils and human health is an ancient one. The Bible depicts Moses as understanding that fertile soil was essential to the well-being of his people in approximately 1400 B.C. as they entered Canaan, and in 400 B.C. Hippocrates provided a list of things that should be considered in a proper medical evaluation, including the ground. Moving into the 18th and 19th Centuries, some North American farmers have been documented as recognizing a link between soils and human vitality. However, the recognition of links between soils and human health by these early people was based on casual observations leading to logical conclusions rather than scientific investigation. In the 1900s the idea that soils influence human health gained considerable traction. At least three chapters in the 1938 USDA Yearbook of Agriculture included recognition of the importance of soil as the origin of many of the mineral elements necessary for human health and in the 1957 USDA Yearbook of Agriculture scientists realized that soils were not only important in the supply of essential nutrients, but that they could also supply toxic levels of elements to the human diet. The U.S. Department of Agriculture established the Plant, Soil and Nutrition Research Unit (PSNRU) on the Cornell University campus in 1940 with a mission to conduct research at the interface of human nutrition and agriculture to improve the nutritional quality and health-promoting properties of food crops. A major human health breakthrough in 1940 was the isolation of antibiotic compounds from soil organisms by the research group at Rutgers University lead by Selman Waksman. Soil microorganisms create antibiotic compounds in an effort to gain a competitive advantage in the soil ecosystem. Humans have been able to isolate those compounds and use them advantageously in the fight against bacterial infections. Waksman was awarded the Nobel Prize in Physiology or Medicine in 1952, the only soil

The Northern Circumpolar Soil Carbon Database: spatially distributed datasets of soil coverage and soil carbon storage in the northern permafrost regions

NASA Astrophysics Data System (ADS)

Hugelius, G.; Tarnocai, C.; Broll, G.; Canadell, J. G.; Kuhry, P.; Swanson, D. K.

2013-01-01

High-latitude terrestrial ecosystems are key components in the global carbon (C) cycle. Estimates of global soil organic carbon (SOC), however, do not include updated estimates of SOC storage in permafrost-affected soils or representation of the unique pedogenic processes that affect these soils. The Northern Circumpolar Soil Carbon Database (NCSCD) was developed to quantify the SOC stocks in the circumpolar permafrost region (18.7 × 106 km2). The NCSCD is a polygon-based digital database compiled from harmonized regional soil classification maps in which data on soil order coverage have been linked to pedon data (n = 1778) from the northern permafrost regions to calculate SOC content and mass. In addition, new gridded datasets at different spatial resolutions have been generated to facilitate research applications using the NCSCD (standard raster formats for use in geographic information systems and Network Common Data Form files common for applications in numerical models). This paper describes the compilation of the NCSCD spatial framework, the soil sampling and soil analytical procedures used to derive SOC content in pedons from North America and Eurasia and the formatting of the digital files that are available online. The potential applications and limitations of the NCSCD in spatial analyses are also discussed. The database has the doi:10.5879/ecds/00000001. An open access data portal with all the described GIS-datasets is available online at: http://www.bbcc.su.se/data/ncscd/.

Effect of soil type and soil management on soil physical, chemical and biological properties in commercial organic olive orchards in Southern Spain

NASA Astrophysics Data System (ADS)

Gomez, Jose Alfonso; Auxiliadora Soriano, Maria; Montes-Borrego, Miguel; Navas, Juan Antonio; Landa, Blanca B.

2014-05-01

One of the objectives of organic agriculture is to maintain and improve soil quality, while simultaneously producing an adequate yield. A key element in organic olive production is soil management, which properly implemented can optimize the use of rainfall water enhancing infiltration rates and controlling competition for soil water by weeds. There are different soil management strategies: eg. weed mowing (M), green manure with surface tillage in spring (T), or combination with animal grazing among the trees (G). That variability in soil management combined with the large variability in soil types on which organic olive trees are grown in Southern Spain, difficult the evaluation of the impact of different soil management on soil properties, and yield as well as its interpretation in terms of improvement of soil quality. This communications presents the results and analysis of soil physical, chemical and biological properties on 58 soils in Southern Spain during 2005 and 2006, and analyzed and evaluated in different studies since them. Those 58 soils were sampled in 46 certified commercial organic olive orchards with four soil types as well as 12 undisturbed areas with natural vegetation near the olive orchards. The four soil types considered were Eutric Regosol (RGeu, n= 16), Eutric Cambisol (CMeu, n=16), Calcaric Regosol (RGca, n=13 soils sampled) and Calcic Cambisol (CMcc), and the soil management systems (SMS) include were 10 light tillage (LT), 16 sheep grazing (G), 10 tillage (T), 10 mechanical mowing (M), and 12 undisturbed areas covered by natural vegetation (NV-C and NV-S). Our results indicate that soil management had a significant effect on olive yield as well as on key soil properties. Among these soil properties are physical ones, such as infiltration rate or bulk density, chemical ones, especially organic carbon concentration, and biological ones such as soil microbial respiration and bacterial community composition. Superimpose to that soil

Mechanisms of Soil Aggregation: a biophysical modeling framework

NASA Astrophysics Data System (ADS)

Ghezzehei, T. A.; Or, D.

2016-12-01

Soil aggregation is one of the main crosscutting concepts in all sub-disciplines and applications of soil science from agriculture to climate regulation. The concept generally refers to adhesion of primary soil particles into distinct units that remain stable when subjected to disruptive forces. It is one of the most sensitive soil qualities that readily respond to disturbances such as cultivation, fire, drought, flooding, and changes in vegetation. These changes are commonly quantified and incorporated in soil models indirectly as alterations in carbon content and type, bulk density, aeration, permeability, as well as water retention characteristics. Soil aggregation that is primarily controlled by organic matter generally exhibits hierarchical organization of soil constituents into stable units that range in size from a few microns to centimeters. However, this conceptual model of soil aggregation as the key unifying mechanism remains poorly quantified and is rarely included in predictive soil models. Here we provide a biophysical framework for quantitative and predictive modeling of soil aggregation and its attendant soil characteristics. The framework treats aggregates as hotspots of biological, chemical and physical processes centered around roots and root residue. We keep track of the life cycle of an individual aggregate from it genesis in the rhizosphere, fueled by rhizodeposition and mediated by vigorous microbial activity, until its disappearance when the root-derived resources are depleted. The framework synthesizes current understanding of microbial life in porous media; water holding and soil binding capacity of biopolymers; and environmental controls on soil organic matter dynamics. The framework paves a way for integration of processes that are presently modeled as disparate or poorly coupled processes, including storage and protection of carbon, microbial activity, greenhouse gas fluxes, movement and storage of water, resistance of soils against

Biological soil crusts in deserts: A short review of their role in soil fertility, stabilization, and water relations

USGS Publications Warehouse

Belnap, Jayne

2003-01-01

Cyanobacteria and cyanolichens dominate most desert soil surfaces as the major component of biological soil crusts (BSC). BSCs contribute to soil fertility in many ways. BSC can increase weathering of parent materials by up to 100 times. Soil surface biota are often sticky, and help retain dust falling on the soil surface; this dust provides many plant-essential nutrients including N, P, K, Mg, Na, Mn, Cu, and Fe. BSCs also provide roughened soil surfaces that slow water runoff and aid in retaining seeds and organic matter. They provide inputs of newly-fixed carbon and nitrogen to soils. They are essential in stabilizing soil surfaces by linking soil particles together with filamentous sheaths, enabling soils to resist both water and wind erosion. These same sheaths are important in keeping soil nutrients from becoming bound into plant-unavailable forms. Experimental disturbances applied in US deserts show soil surface impacts decrease N and C inputs from soil biota by up to 100%. The ability to hold aeolian deposits in place is compromised, and underlying soils are exposed to erosion. While most undisturbed sites show little sediment production, disturbance by vehicles or livestock produces up to 36 times more sediment production, with soil movement initiated at wind velocities well below commonly-occurring wind speeds. Winds across disturbed areas can quickly remove this material from the soil surface, thereby potentially removing much of current and future soil fertility. Thus, reduction in the cover of cyanophytes in desert soils can both reduce fertility inputs and accelerate fertility losses.

BOREAS TE-1 SSA Soil Lab Data

NASA Technical Reports Server (NTRS)

Hall, Forrest G. (Editor); Knapp, David E. (Editor); Nerbas, Tim; Anderson, Darwin

2000-01-01

This data set was collected by TE-1 to provide a set of soil properties for BOREAS investigators in the SSA. The soil samples were collected at sets of soil pits in 1993 and 1994. Each set of soil pits was in the vicinity of one of the five flux towers in the BOREAS SSA. The collected soil samples were sent to a lab, where the major soil properties were determined. These properties include, but are not limited to, soil horizon; dry soil color; pH; bulk density; total, organic, and inorganic carbon; electric conductivity; cation exchange capacity; exchangeable sodium, potassium, calcium, magnesium, and hydrogen; water content at 0.01, 0.033, and 1.5 MPascals; nitrogen; phosphorus; particle size distribution; texture; pH of the mineral soil and of the organic soil; extractable acid; and sulfur. The data are stored in tabular ASCII text files. The data files are available on a CD-ROM (see document number 20010000884), or from the Oak Ridge National Laboratory (ORNL) Distributed Active Archive Center (DAAC).

Spatial Distribution of Fungal Communities in an Arable Soil

PubMed Central

Moll, Julia; Hoppe, Björn; König, Stephan; Wubet, Tesfaye; Buscot, François; Krüger, Dirk

2016-01-01

Fungi are prominent drivers of ecological processes in soils, so that fungal communities across different soil ecosystems have been well investigated. However, for arable soils taxonomically resolved fine-scale studies including vertical itemization of fungal communities are still missing. Here, we combined a cloning/Sanger sequencing approach of the ITS/LSU region as marker for general fungi and of the partial SSU region for arbuscular mycorrhizal fungi (AMF) to characterize the microbiome in different maize soil habitats. Four compartments were analyzed over two annual cycles 2009 and 2010: a) ploughed soil in 0–10 cm, b) rooted soil in 40–50 cm, c) root-free soil in 60–70 cm soil depth and d) maize roots. Ascomycota was the most dominant phylum across all compartments. Fungal communities including yeasts and AMF differed strongly between compartments. Inter alia, Tetracladium, the overall largest MOTU (molecular operational taxonomic unit), occurred in all compartments, whereas Trichosporon dominated all soil compartments. Sequences belonging to unclassified Helotiales were forming the most abundant MOTUs exclusively present in roots. This study gives new insights on spatial distribution of fungi and helps to link fungal communities to specific ecological properties such as varying resources, which characterize particular niches of the heterogeneous soil environment. PMID:26840453

Variation in Soil Respiration across Soil and Vegetation Types in an Alpine Valley

PubMed Central

Rubin, Aurélie

2016-01-01

Background and Aims Soils of mountain regions and their associated plant communities are highly diverse over short spatial scales due to the heterogeneity of geological substrates and highly dynamic geomorphic processes. The consequences of this heterogeneity for biogeochemical transfers, however, remain poorly documented. The objective of this study was to quantify the variability of soil-surface carbon dioxide efflux, known as soil respiration (Rs), across soil and vegetation types in an Alpine valley. To this aim, we measured Rs rates during the peak and late growing season (July-October) in 48 plots located in pastoral areas of a small valley of the Swiss Alps. Findings Four herbaceous vegetation types were identified, three corresponding to different stages of primary succession (Petasition paradoxi in pioneer conditions, Seslerion in more advanced stages and Poion alpinae replacing the climactic forests), as well as one (Rumicion alpinae) corresponding to eutrophic grasslands in intensively grazed areas. Soils were developed on calcareous alluvial and colluvial fan deposits and were classified into six types including three Fluvisols grades and three Cambisols grades. Plant and soil types had a high level of co-occurrence. The strongest predictor of Rs was soil temperature, yet we detected additional explanatory power of sampling month, showing that temporal variation was not entirely reducible to variations in temperature. Vegetation and soil types were also major determinants of Rs. During the warmest month (August), Rs rates varied by over a factor three between soil and vegetation types, ranging from 2.5 μmol m-2 s-1 in pioneer environments (Petasition on Very Young Fluvisols) to 8.5 μmol m-2 s-1 in differentiated soils supporting nitrophilous species (Rumicion on Calcaric Cambisols). Conclusions Overall, this study provides quantitative estimates of spatial and temporal variability in Rs in the mountain environment, and demonstrates that estimations of

Visually assessing the level of development and soil surface stability of cyanobacterially dominated biological soil crusts

USGS Publications Warehouse

Belnap, J.; Phillips, S.L.; Witwicki, D.L.; Miller, M.E.

2008-01-01

Biological soil crusts (BSCs) are an integral part of dryland ecosystems and often included in long-term ecological monitoring programs. Estimating moss and lichen cover is fairly easy and non-destructive, but documenting cyanobacterial level of development (LOD) is more difficult. It requires sample collection for laboratory analysis, which causes soil surface disturbance. Assessing soil surface stability also requires surface disturbance. Here we present a visual technique to assess cyanobacterial LOD and soil surface stability. We define six development levels of cyanobacterially dominated soils based on soil surface darkness. We sampled chlorophyll a concentrations (the most common way of assessing cyanobacterial biomass), exopolysaccharide concentrations, and soil surface aggregate stability from representative areas of each LOD class. We found that, in the laboratory and field, LOD classes were effective at predicting chlorophyll a soil concentrations (R2=68-81%), exopolysaccharide concentrations (R2=71%), and soil aggregate stability (R2=77%). We took representative photos of these classes to construct a field guide. We then tested the ability of field crews to distinguish these classes and found this technique was highly repeatable among observers. We also discuss how to adjust this index for the different types of BSCs found in various dryland regions.

Phosphorus in global agricultural soils: spatially explicit modelling of soil phosphorus and crop uptake for 1900 to 2010

NASA Astrophysics Data System (ADS)

Zhang, J.; Beusen, A.; Bouwman, L.; Apeldoorn, D. V.; Yu, C.

2016-12-01

Phosphorus (P) plays a vital role in global crop production and food security. To explore the global P status of soils, in this study we developed a spatially explicit version of a two-pool dynamic soil P model at 0.5°resolution. With this model, we analyzed the historical changes of soil P inputs (including manure and inorganic P fertilizer) from 1900 to 2010, reproduced the historical crop P uptake, calculated the phosphorus use efficiency (PUE) and conducted a comprehensive inventory of soil P pools and P budgets (deficit and surplus) in global soils under croplands. Our results suggest that the spatially explicit model is capable of simulating the long-term soil P budget changes and crop uptake, with model simulations closely matching historical P uptake for cropland in all countries. The global P inputs from fertilizers and manure increased from 2 Tg P in 1900 to 23 Tg P in 2010 with great variation across different regions and countries of the world. The magnitude of crop uptake has also changed rapidly over the 20th century: according to our model, crop P uptake per hectare in Western Europe increased by more than three times while the total soil P stock per hectare increased by close to 37% due to long-term P surplus application, with a slight decrease in recent years. Croplands in China (total P per hectare slight decline during 1900-1970, +34% since 1970) and India (total P per hectare gradual increase by 14% since 1900, 6% since 1970) are currently in the phase of accumulation.The total soil P content per hectare in Sub-Saharan Africa has slightly decreased since 1900.Our model is a promising tool to analyze the changes in the soil P status and the capacity of soils to supply P to crops, including future projections of required nutrient inputs.

Reducing Methyl Halide Emissions from Soils

NASA Astrophysics Data System (ADS)

Yates, S. R.; Xuan, R.; Ashworth, D.; Luo, L.

2011-12-01

Volatilization and soil transformation are major pathways by which pesticides dissipate from treated agricultural soil. Methyl bromide (MeBr) emissions from agricultural fumigation can lead to depletion of the stratospheric ozone layer. This has led to a gradual phase-out of MeBr and replacement by other halogenated chemicals. However, MeBr continues to be widely used under Critical Use Exemptions and development of emission-reduction strategies remains important. Several methods to reduce emissions of MeBr, and other halogenated soil fumigants, have been developed and are currently being tested under field conditions. In this paper, several approaches for reducing fumigant emissions to the atmosphere are described and include the use of virtually impermeable films, the creation of reactive soil barriers and a recently developed reactive film which was designed to limit loss of MeBr from soil without adding any material to the soil surface. Ammonium thiosulfate (ATS) was used to create a reactive layer. For a reactive soil layer, ATS was sprayed on the soil surface or incorporated to a depth of 1-2 cm. For the reactive film, ATS was placed between two layers of plastic film. The lower plastic layer was a high-density polyethylene film (HDPE), which is readily permeable to MeBr. The upper layer was a virtually impermeable film (VIF) and limits MeBr diffusion. MeBr diffusion and transformation through VIFs and reactive layers were tested in laboratory and field experiments. Although ineffective when dry, when sufficient water was present, reactive barriers substantially depleted halogenated fumigants, including MeBr. When ATS was activated in laboratory experiments, MeBr half-life was about 9.0 h (20C) in a reactive film barrier, and half life decreased with increasing temperature. When the soil was covered with VIF, less than 10% of the added MeBr diffused through the film and the remainder was transformed within the soil. This compares with 60 to 90% emission

Observations of net soil exchange of CO2 in a dryland show experimental warming increases carbon losses in biocrust soils

USGS Publications Warehouse

Darrouzet-Nardi, Anthony N.; Reed, Sasha C.; Grote, Ed; Belnap, Jayne

2015-01-01

Many arid and semiarid ecosystems have soils covered with well-developed biological soil crust communities (biocrusts) made up of mosses, lichens, cyanobacteria, and heterotrophs living at the soil surface. These communities are a fundamental component of dryland ecosystems, and are critical to dryland carbon (C) cycling. To examine the effects of warming temperatures on soil C balance in a dryland ecosystem, we used infrared heaters to warm biocrust-dominated soils to 2 °C above control conditions at a field site on the Colorado Plateau, USA. We monitored net soil exchange (NSE) of CO2 every hour for 21 months using automated flux chambers (5 control and 5 warmed chambers), which included the CO2 fluxes of the biocrusts and the soil beneath them. We observed measurable photosynthesis in biocrust soils on 12 % of measurement days, which correlated well with precipitation events and soil wet-up. These days included several snow events, providing what we believe to be the first evidence of substantial photosynthesis underneath snow by biocrust organisms in drylands. Overall, biocrust soils in both control and warmed plots were net CO2 sources to the atmosphere, with control plots losing 62 ± 8 g C m−2 (mean ± SE) over the first year of measurement and warmed plots losing 74 ± 9 g C m−2. Between control and warmed plots, the difference in soil C loss was uncertain over the course of the entire year due to large and variable rates in spring, but on days during which soils were wet and crusts were actively photosynthesizing, biocrusts that were warmed by 2 °C had a substantially more negative C balance (i.e., biocrust soils took up less C and/or lost more C in warmed plots). Taken together, our data suggest a substantial risk of increased C loss from biocrust soils with higher future temperatures, and highlight a robust capacity to predict CO2 exchange in biocrust soils using easily measured environmental parameters.

Microflora in soils of desert regions

NASA Technical Reports Server (NTRS)

Cameron, R. E.

1970-01-01

Desert soil samples, collected using aseptic techniques, are low in organic matter and cation exchange capacity. Aerobic and microaerophilic bacteria are most abundant, next are algae and molds. Chemical and physical properties are determined by standard procedures, including the Kjeldahl method and the use of Munsell soil color charts.

Assessment of Two Solid Anaerobic Digestate Soil Amendments for Effects on Soil Quality and Biosolarization Efficacy.

PubMed

Fernández-Bayo, Jesús D; Achmon, Yigal; Harrold, Duff R; McCurry, Dlinka G; Hernandez, Katie; Dahlquist-Willard, Ruth M; Stapleton, James J; VanderGheynst, Jean S; Simmons, Christopher W

2017-05-03

Anaerobic digestion is an organic waste bioconversion process that produces biofuel and digestates. Digestates have potential to be applied as soil amendment to improve properties for crop production including phytonutrient content and pest load. Our objective was to assess the impact of solid anaerobic digestates on weed seed inactivation and soil quality upon soil biosolarization (a pest control technique that combines solar heating and amendment-induced microbial activity). Two solid digestates from thermophilic (TD) and mesophilic (MD) digesters were tested. The solarized TD-amended samples presented significantly higher mortality of Brassica nigra (71%, P = 0.032) than its equivalent incubated at room temperature. However, biosolarization with digestate amendment led to decreased weed seed mortality in certain treatments. The plant-available water, total C, and extractable P and K were significantly increased (P < 0.05) in the incubated amended soils. The results confirm the potential of digestates as beneficial soil amendments. Further studies are needed to elucidate the impacts of digestate stability on biosolarization efficacy and soil properties.

Improved Cookstove Training Manual. No. T-40.

ERIC Educational Resources Information Center

Lillywhite, Malcolm

This document was developed as a training manual for people interested in various types of appropriate technologies related to improved cookstoves. The three types of cookstoves included in the manual are earthen, ceramic, and metal (or a combination of metal and ceramic). The training sessions described deal with: (1) an orientation to the…

Soil Organic Carbon dynamics in agricultural soils of Veneto Region

NASA Astrophysics Data System (ADS)

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

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.

The Integration of SMOS Soil Moisture in a Consistent Soil Moisture Climate Record

NASA Astrophysics Data System (ADS)

de Jeu, Richard; Kerr, Yann; Wigneron, Jean Pierre; Rodriguez-Fernandez, Nemesio; Al-Yaari, Amen; van der Schalie, Robin; Dolman, Han; Drusch, Matthias; Mecklenburg, Susanne

2015-04-01

Recently, a study funded by the European Space Agency (ESA) was set up to provide guidelines for the development of a global soil moisture climate record with a special emphasis on the integration of SMOS. Three different data fusion approaches were designed and implemented on 10 year passive microwave data (2003-2013) from two different satellite sensors; the ESA Soil Moisture Ocean Salinity Mission (SMOS) and the NASA/JAXA Advanced Scanning Microwave Radiometer (AMSR-E). The AMSR-E data covered the period from January 2003 until Oct 2011 and SMOS data covered the period from June 2010 until the end of 2013. The fusion approaches included a neural network approach (Rodriguez-Fernandez et al., this conference session HS6.4), a regression approach (Wigneron et al., 2004), and an approach based on the baseline algorithm of ESAs current Climate Change Initiative soil moisture program, the Land Parameter Retrieval Model (Van der Schalie et al., this conference session HS6.4). With this presentation we will show the first results from this study including a description of the different approaches and the validation activities using both globally covered modeled datasets and ground observations from the international soil moisture network. The statistical validation analyses will give us information on the temporal and spatial performance of the three different approaches. Based on these results we will then discuss the next steps towards a seamless integration of SMOS in a consistent soil moisture climate record. References Wigneron J.-P., J.-C. Calvet, P. de Rosnay, Y. Kerr, P. Waldteufel, K. Saleh, M. J. Escorihuela, A. Kruszewski, 'Soil Moisture Retrievals from Bi-Angular L-band Passive Microwave Observations', IEEE Trans. Geosc. Remote Sens. Let., vol 1, no. 4, 277-281, 2004.

Some aspects of remediation of contaminated soils

NASA Astrophysics Data System (ADS)

Bech, Jaume; Korobova, Elena; Abreu, Manuela; Bini, Claudio; Chon, Hyo-Taek; Pérez-Sirvent, Carmen; Roca, Núria

2014-05-01

Soils are essential components of the environment, a limited precious and fragile resource, the quality of which should be preserved. The concentration, chemical form and distribution of potential harmful elements in soils depends on parent rocks, weathering, soil type and soil use. However, their concentration can be altered by mismanagement of industrial and mining activities, energy generation, traffic increase, overuse of agrochemicals, sewage sludge and waste disposal, causing contamination, environmental problems and health concerns. Heavy metals, some metalloids and radionuclides are persistent in the environment. This persistence hampers the cost/efficiency of remediation technologies. The choice of the most appropriate soil remediation techniques depends of many factors and essentially of the specific site. This contribution aims to offer an overview of the main remediation methods in contaminated soils. There are two main groups of technologies: the first group dealing with containment and confinement, minimizing their toxicity, mobility and bioavailability. Containment measures include covering, sealing, encapsulation and immobilization and stabilization. The second group, remediation with decontamination, is based on the remotion, clean up and/or destruction of contaminants. This group includes mechanical procedures, physical separations, chemical technologies such as soil washing with leaching or precipitation of harmful elements, soil flushing, thermal treatments and electrokinetic technologies. There are also two approaches of biological nature: bioremediation and phytoremediation. Case studies from Chile, Ecuador, Italy, Korea, Peru, Portugal, Russia and Spain, will be discussed in accordance with the time available.

Physical soil quality indicators for monitoring British soils

NASA Astrophysics Data System (ADS)

Corstanje, Ron; Mercer, Theresa G.; Rickson, Jane R.; Deeks, Lynda K.; Newell-Price, Paul; Holman, Ian; Kechavarsi, Cedric; Waine, Toby W.

2017-09-01

Soil condition or quality determines its ability to deliver a range of functions that support ecosystem services, human health and wellbeing. The increasing policy imperative to implement successful soil monitoring programmes has resulted in the demand for reliable soil quality indicators (SQIs) for physical, biological and chemical soil properties. The selection of these indicators needs to ensure that they are sensitive and responsive to pressure and change, e.g. they change across space and time in relation to natural perturbations and land management practices. Using a logical sieve approach based on key policy-related soil functions, this research assessed whether physical soil properties can be used to indicate the quality of British soils in terms of their capacity to deliver ecosystem goods and services. The resultant prioritised list of physical SQIs was tested for robustness, spatial and temporal variability, and expected rate of change using statistical analysis and modelling. Seven SQIs were prioritised: soil packing density, soil water retention characteristics, aggregate stability, rate of soil erosion, depth of soil, soil structure (assessed by visual soil evaluation) and soil sealing. These all have direct relevance to current and likely future soil and environmental policy and are appropriate for implementation in soil monitoring programmes.

10Be accumulation in a soil chronosequence

USGS Publications Warehouse

Pavich, M.J.; Brown, L.; Klein, J.; Middleton, R.

1984-01-01

We have measured the concentration of the cosmogenic isotope 10Be in soil samples from various horizons at six sites, including three independently dated Rappahannock River terraces and a previously undated Piedmont soil to which we have assigned an age. All of the incident 10Be can be accounted for in one of these soils and a second is within a factor of two. In three soils, whose concentrations vary widely with depth, a significant fraction of the incident 10Be cannot be accounted for. Incomplete sampling, and enhanced Be mobility caused by organic components, are the probable reasons for the low inventory of Be from these three soils. Overall, the data from these six sites indicate that 10Be accumulation could be used to assign ages to soils if Be is not mobilized and lost from the soil profile. ?? 1984.

Coupling rainfall observations and satellite soil moisture for predicting event soil loss in Central Italy

NASA Astrophysics Data System (ADS)

Todisco, Francesca; Brocca, Luca; Termite, Loris Francesco; Wagner, Wolfgang

2015-04-01

The accuracy of water soil loss prediction depends on the ability of the model to account for effects of the physical phenomena causing the output and the accuracy by which the parameters have been determined. The process based models require considerable effort to obtain appropriate parameter values and their failure to produce better results than achieved using the USLE/RUSLE model, encourages the use of the USLE/RUSLE model in roles of which it was not designed. In particular it is widely used in watershed models even at the event temporal scale. At hillslope scale, spatial variability in soil and vegetation result in spatial variations in soil moisture and consequently in runoff within the area for which soil loss estimation is required, so the modeling approach required to produce those estimates needs to be sensitive to those spatial variations in runoff. Some models include explicit consideration of runoff in determining the erosive stresses but this increases the uncertainty of the prediction due to the difficulty in parameterising the models also because the direct measures of surface runoff are rare. The same remarks are effective also for the USLE/RUSLE models including direct consideration of runoff in the erosivity factor (i.e. USLE-M by Kinnell and Risse, 1998, and USLE-MM by Bagarello et al., 2008). Moreover actually most of the rainfall-runoff models are based on the knowledge of the pre-event soil moisture that is a fundamental variable in the rainfall-runoff transformation. In addiction soil moisture is a readily available datum being possible to have easily direct pre-event measures of soil moisture using in situ sensors or satellite observations at larger spatial scale; it is also possible to derive the antecedent water content with soil moisture simulation models. The attempt made in the study is to use the pre-event soil moisture to account for the spatial variation in runoff within the area for which the soil loss estimates are required. More

Soil magnetic susceptibility reflects soil moisture regimes and the adaptability of tree species to these regimes

USGS Publications Warehouse

Wang, J.-S.; Grimley, D.A.; Xu, C.; Dawson, J.O.

2008-01-01

Flooded, saturated or poorly drained soils are frequently anaerobic, leading to dissolution of the strongly magnetic minerals, magnetite and maghemite, and a corresponding decrease in soil magnetic susceptibility (MS). In this study of five temperate deciduous forests in east-central Illinois, USA, mean surface soil MS was significantly higher adjacent to upland tree species (31 ?? 10-5 SI) than adjacent to floodplain or lowland tree species (17 ?? 10-5 SI), when comparing regional soils with similar parent material of loessal silt. Although the sites differ in average soil MS for each tree species, the relative order of soil MS means for associated tree species at different locations is similar. Lowland tree species, Celtis occidentalis L., Ulmus americana L., Acer saccharinum L., Carya laciniosa (Michx. f.) Loud., and Fraxinus pennsylvanica Marsh. were associated with the lowest measured soil MS mean values overall and at each site. Tree species' flood tolerance rankings increased significantly, as soil MS values declined, the published rankings having significant correlations with soil MS values for the same species groups. The three published classifications of tree species' flood tolerance were significantly correlated with associated soil MS values at all sites, but most strongly at Allerton Park, the site with the widest range of soil drainage classes and MS values. Using soil MS measurements in forests with soil parent material containing similar initial levels of strongly magnetic minerals can provide a simple, rapid and quantitative method to classify soils according to hydric regimes, including dry conditions, and associated plant composition. Soil MS values thus have the capacity to quantify the continuum of hydric tolerances of tree species and guide tree species selection for reforestation. ?? 2007 Elsevier B.V. All rights reserved.

Soil fauna and soil microflora as possible indicators of soil pollution.

PubMed

Eijsackers, H

1983-09-01

Research on biological indicators of soil pollution is hampered by soil variability and temporal and spatial fluctuations of numbers of soil animals. These characters on the other hand promote a high biological diversity in the soil. A high diversity combined with persistent soil pollutants increases the chance to select good indicators. However research on these topics is still limited. Examples of specific indicators are the changed arthropod species patterns due to pesticide influence and the changed soil enzyme activity under the influence of specific heavy metals. Another approach is to look for organisms that give a general indication of soil pollution. In this respect the earthworm species Allolobophora caliginosa proved to be sensitive for different types of manure especially pig manure with copper, for sewage sludge, for municipal waste compost and for fly ash. A third way of indication is by organisms accumulating pollutants. For some heavy metals (Cd, Zn), earthworms are very efficient accumulators. More research is needed especially on the specific relation between biological responses and abiotic soil characteristics.

Soil paints as a tool to increase soil awareness among different publics

NASA Astrophysics Data System (ADS)

Muggler, Cristine C.

2013-04-01

The Earth Sciences Museum Alexis Dorofeef at the Soil Department of the Federal University of Viçosa (UFV), Minas Gerais, Brazil, was opened in 1993 with a goal to sensibilize its public about soils, besides the usual geological approach. Since its opening, many of the guided visits include an activity of painting or modelling with soil materials. Such activities have the aim to familiarize people about the properties of soils, in special, colours, consistencies and textures in a joyful way. The tropical soils of the region offer a wide diversity of colours and textures that wonders and intrigues people in general. With time, some of the visitors as well as the museum team started to make trials how it would be to paint walls with the soil paints. It became a project to develop a social technology since the soil paints could be easily prepared and used at much lower cost than industrial paints. Additionally, to have the house painted offers populations living in the peripheral areas of the town of Viçosa the possibility to increase their quality of life by embellishing the surroundings where they live. After the basic know how was developed, the Museum and other extension groups of UFV started to train people in doing it. A brochure was published and the technique spread rapidly in the region and to other parts of the state and country as well. The workshops on soil paint preparation and use, offered by the Museum are open to a much diversified public: school children, professional painters, farmers of the landless movement, etc. The workshops have been taken as an opportunity to approach soils and its importance to life and environment. They start with questions about how people consider and see soils. From this starting point, soil formation processes and soil properties are introduced and discussed with the group. This is followed by the discussion of landscapes and where the soil materials can be collected and what are the differences to be expected between

Soils

Treesearch

Emily Moghaddas; Ken Hubbert

2014-01-01

When managing for resilient forests, each soil’s inherent capacity to resist and recover from changes in soil function should be evaluated relative to the anticipated extent and duration of soil disturbance. Application of several key principles will help ensure healthy, resilient soils: (1) minimize physical disturbance using guidelines tailored to specific soil types...

Observing and modeling links between soil moisture, microbes and CH4 fluxes from forest soils

NASA Astrophysics Data System (ADS)

Christiansen, Jesper; Levy-Booth, David; Barker, Jason; Prescott, Cindy; Grayston, Sue

2017-04-01

community responds different to environmental change dependent on the soil moisture regime. These results are important to include in future modeling efforts to predict changes in soil-atmosphere exchange of CH4 under global change.

Soil abandonment in artificial soil terraces in marginal areas. Preliminary results of a case of water shortage effect in soils from Sultanate of Oman.

NASA Astrophysics Data System (ADS)

Saadi, Sara Kalifah Al; Kindi, Samaya Salim Al; Pracejus, Bernhard; Moraetis, Daniel

2016-04-01

Soil abandonment is taking place in marginal land areas in Sultanate of Oman. Artificial soil terraces in high elevation rocky mountainous areas left without agricultural activities due to water shortage. Soil terraces have been established approximately 700 years ago and constitute a significant part of the Oman cultural and natural heritage. The present study investigates the soil state in those areas and seeks the possible reasons for the land abandonment. Questionnaires were prepared to interview the opinion of the local people. In addition, meteorological data were gathered to analyze the rain patterns in the area and most importantly, six soil profiles in two different areas in marginal rocky areas of Oman were sampled. The soils are in artificial terraces in Wijma and Hadash villages with elevation of 1247 and 1469 m respectively at mountainous slopes of 20 to 45 degrees. Most of the land was abandoned the last 20 years, while one terrace had agriculture activity 3 years ago. The questioners and interviews showed that water shortage was the reason of land abandonment. The rain patterns show a reduction of annual precipitation at least the last 10 years of available metrological data in the area. The total soil depth in the six soil profiles was between 33 to 70 cm. The main horizons include AC and C and there was a characteristic hard soil horizon in most of the soil profiles with accumulation of carbonate minerals (caliche). The soil pH was mainly alkaline between 7.5 to 8.1 and the electrical conductivity range between 42 to 859 μS/cm. A horizonization in electrical conductivity showed more dissolved solids in lower horizons compare to the upper 10 cm of the soil and this was coinciding with the hard layers in lower soil profiles. It appeared that several hundred years (or maximum 1000 years) old soils showed the development of hard soil layers which are characteristic in arid areas. The upper soil layers showed low conductivity probably due to surface

Soil geomorphic classification, soil taxonomy, and effects on soil richness assessments