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W. M. Iversen - One of the best experts on this subject based on the ideXlab platform.
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Estimating in Situ Soil–water retention and field water capacity in two contrasting Soil textures
Irrigation Science, 2009Co-Authors: J. D. Jabro, R. G. Evans, W. M. IversenAbstract:A priori knowledge of the in Situ Soil field water capacity (FWC) and the Soil-water retention curve for Soils is important for the effective irrigation management and scheduling of many crops. The primary objective of this study was to estimate the in Situ FWC using the Soil-water retention curve developed from volumetric water content ( θ ), and water potential (ψ) data collected in the field by means of Soil moisture sensors in two contrasting-textured Soils. The two study Soils were Lihen sandy loam and Savage clay loam. Six metal frames 117 cm × 117 cm × 30 cm high were inserted into the Soil to a depth of 5–10 cm at approximately 40 m intervals on a 200 m transect. Two Time Domain Reflectrometry (TDR) sensors were installed in the center of the frame and two Watermark (WM) sensors were installed in the SW corner at 15 and 30 cm depths to continuously monitor Soil θ and ψ, respectively. A neutron probe (NP) access tube was installed in the NE corner of each frame to measure Soil θ used for TDR calibration. The upper 50–60 cm of Soil inside each frame was saturated with intermittent application of approximately 18–20 cm of water. Frames were then covered with plastic tarps. The Campbell and Gardner equations best fit the Soil–water retention curves for sandy loam and clay loam Soils, respectively. Based on the relationship between Soil ψ and elapsed time following cessation of infiltration, we calculated that the field capacity time ( t _FWC) were reached at approximately 50 and 450 h, respectively, for sandy loam and clay loam Soils. Soil-water retention curves showed that θ values at FWC ( θ _FWC) were approximately 0.228 and 0.344 m^3 m^−3, respectively, for sandy loam and clay loam Soils. The estimated θ _FWC values were within the range of the measured θ _FWC values from the NP and gravimetric methods. The TDR and WM sensors provided accurate in Situ Soil–water retention data from simultaneous Soil θ and ψ measurements that can be used in Soil-water processes, irrigation scheduling, modeling and chemical transport.
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Estimating in Situ Soil-water retention and field water capacity in two contrasting Soil textures
Irrigation Science, 2008Co-Authors: J. D. Jabro, R. G. Evans, Yunseop Kim, W. M. IversenAbstract:A priori knowledge of the in Situ Soil field water capacity (FWC) and the Soil-water retention curve for Soils is important for the effective irrigation management and scheduling of many crops. The primary objective of this study was to estimate the in Situ FWC using the Soil-water retention curve developed from volumetric water content (θ), and water potential (ψ) data collected in the field by means of Soil moisture sensors in two contrasting-textured Soils. The two study Soils were Lihen sandy loam and Savage clay loam. Six metal frames 117 cm × 117 cm × 30 cm high were inserted into the Soil to a depth of 5–10 cm at approximately 40 m intervals on a 200 m transect. Two Time Domain Reflectrometry (TDR) sensors were installed in the center of the frame and two Watermark (WM) sensors were installed in the SW corner at 15 and 30 cm depths to continuously monitor Soil θ and ψ, respectively. A neutron probe (NP) access tube was installed in the NE corner of each frame to measure Soil θ used for TDR calibration. The upper 50–60 cm of Soil inside each frame was saturated with intermittent application of approximately 18–20 cm of water. Frames were then covered with plastic tarps. The Campbell and Gardner equations best fit the Soil–water retention curves for sandy loam and clay loam Soils, respectively. Based on the relationship between Soil ψ and elapsed time following cessation of infiltration, we calculated that the field capacity time (t FWC) were reached at approximately 50 and 450 h, respectively, for sandy loam and clay loam Soils. Soil-water retention curves showed that θ values at FWC (θ FWC) were approximately 0.228 and 0.344 m3 m−3, respectively, for sandy loam and clay loam Soils. The estimated θ FWC values were within the range of the measured θ FWC values from the NP and gravimetric methods. The TDR and WM sensors provided accurate in Situ Soil–water retention data from simultaneous Soil θ and ψ measurements that can be used in Soil-water processes, irrigation scheduling, modeling and chemical transport.
J. D. Jabro - One of the best experts on this subject based on the ideXlab platform.
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Estimating in Situ Soil–water retention and field water capacity in two contrasting Soil textures
Irrigation Science, 2009Co-Authors: J. D. Jabro, R. G. Evans, W. M. IversenAbstract:A priori knowledge of the in Situ Soil field water capacity (FWC) and the Soil-water retention curve for Soils is important for the effective irrigation management and scheduling of many crops. The primary objective of this study was to estimate the in Situ FWC using the Soil-water retention curve developed from volumetric water content ( θ ), and water potential (ψ) data collected in the field by means of Soil moisture sensors in two contrasting-textured Soils. The two study Soils were Lihen sandy loam and Savage clay loam. Six metal frames 117 cm × 117 cm × 30 cm high were inserted into the Soil to a depth of 5–10 cm at approximately 40 m intervals on a 200 m transect. Two Time Domain Reflectrometry (TDR) sensors were installed in the center of the frame and two Watermark (WM) sensors were installed in the SW corner at 15 and 30 cm depths to continuously monitor Soil θ and ψ, respectively. A neutron probe (NP) access tube was installed in the NE corner of each frame to measure Soil θ used for TDR calibration. The upper 50–60 cm of Soil inside each frame was saturated with intermittent application of approximately 18–20 cm of water. Frames were then covered with plastic tarps. The Campbell and Gardner equations best fit the Soil–water retention curves for sandy loam and clay loam Soils, respectively. Based on the relationship between Soil ψ and elapsed time following cessation of infiltration, we calculated that the field capacity time ( t _FWC) were reached at approximately 50 and 450 h, respectively, for sandy loam and clay loam Soils. Soil-water retention curves showed that θ values at FWC ( θ _FWC) were approximately 0.228 and 0.344 m^3 m^−3, respectively, for sandy loam and clay loam Soils. The estimated θ _FWC values were within the range of the measured θ _FWC values from the NP and gravimetric methods. The TDR and WM sensors provided accurate in Situ Soil–water retention data from simultaneous Soil θ and ψ measurements that can be used in Soil-water processes, irrigation scheduling, modeling and chemical transport.
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Estimating in Situ Soil-water retention and field water capacity in two contrasting Soil textures
Irrigation Science, 2008Co-Authors: J. D. Jabro, R. G. Evans, Yunseop Kim, W. M. IversenAbstract:A priori knowledge of the in Situ Soil field water capacity (FWC) and the Soil-water retention curve for Soils is important for the effective irrigation management and scheduling of many crops. The primary objective of this study was to estimate the in Situ FWC using the Soil-water retention curve developed from volumetric water content (θ), and water potential (ψ) data collected in the field by means of Soil moisture sensors in two contrasting-textured Soils. The two study Soils were Lihen sandy loam and Savage clay loam. Six metal frames 117 cm × 117 cm × 30 cm high were inserted into the Soil to a depth of 5–10 cm at approximately 40 m intervals on a 200 m transect. Two Time Domain Reflectrometry (TDR) sensors were installed in the center of the frame and two Watermark (WM) sensors were installed in the SW corner at 15 and 30 cm depths to continuously monitor Soil θ and ψ, respectively. A neutron probe (NP) access tube was installed in the NE corner of each frame to measure Soil θ used for TDR calibration. The upper 50–60 cm of Soil inside each frame was saturated with intermittent application of approximately 18–20 cm of water. Frames were then covered with plastic tarps. The Campbell and Gardner equations best fit the Soil–water retention curves for sandy loam and clay loam Soils, respectively. Based on the relationship between Soil ψ and elapsed time following cessation of infiltration, we calculated that the field capacity time (t FWC) were reached at approximately 50 and 450 h, respectively, for sandy loam and clay loam Soils. Soil-water retention curves showed that θ values at FWC (θ FWC) were approximately 0.228 and 0.344 m3 m−3, respectively, for sandy loam and clay loam Soils. The estimated θ FWC values were within the range of the measured θ FWC values from the NP and gravimetric methods. The TDR and WM sensors provided accurate in Situ Soil–water retention data from simultaneous Soil θ and ψ measurements that can be used in Soil-water processes, irrigation scheduling, modeling and chemical transport.
H L Jennings - One of the best experts on this subject based on the ideXlab platform.
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In Situ Soil Venting - Full Scale Test, Hill AFB, Guidance Document. Volume 2
1991Co-Authors: D.w. Depaoli, S.e. Herbes, J H Wilson, D K Solomon, H L JenningsAbstract:Abstract : The purpose of this project was to demonstrate a full-scale in Situ Soil venting technology and to carefully document the design, operation and performance of this system so that it could be applied at other Air Force contaminated sites. Although this technology is now commercially available, its ability to fully remediate jet fuel spills had never been proven, nor had the full-scale costs ever been validated when catalytic incineration is used as an emission control method. ESL Technical Report 90-21 is in three volumes. The first volume is a complete literature review of previous Soil venting research and field work. Volume II is a guidance manual which provides important design information and describes methods of pilot testing this technology prior to full-scale application. Results of the Hill AFB test are included in Volume III. These publications will provide invaluable information to Air Force engineers responsible for cleaning up chemically contaminated sites.
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In Situ Soil Venting - Full Scale Test, Hill AFB. Volume 3. Guidance Document, Literature Review
1991Co-Authors: D.w. Depaoli, S.e. Herbes, J H Wilson, D K Solomon, H L JenningsAbstract:Abstract : The purpose of this project was to demonstrate a full-scale in Situ Soil venting technology and to carefully document the design, operation and performance of this system so that it could be applied at other Air Force contaminated sites. Although this technology is now commercially available, its ability to fully remediate jet fuel spills had never been proven, nor had the full-scale costs ever been validated when catalytic incineration is used as an emission control method. ESL Technical Report 90-21 is in three volumes. The first volume is a complete literature review of previous Soil venting research and field work. Volume II is a guidance manual which provides important design information and describes methods of pilot testing this technology prior to full-scale application. Results of the Hill AFB test are included in Volume III. These publications will provide invaluable information to Air Force engineers responsible for cleaning up chemically contaminated sites.... Soil venting, Fuel spill remediation, Bioremediation, Vacuum extraction.
D K Solomon - One of the best experts on this subject based on the ideXlab platform.
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In Situ Soil Venting - Full Scale Test, Hill AFB, Guidance Document. Volume 2
1991Co-Authors: D.w. Depaoli, S.e. Herbes, J H Wilson, D K Solomon, H L JenningsAbstract:Abstract : The purpose of this project was to demonstrate a full-scale in Situ Soil venting technology and to carefully document the design, operation and performance of this system so that it could be applied at other Air Force contaminated sites. Although this technology is now commercially available, its ability to fully remediate jet fuel spills had never been proven, nor had the full-scale costs ever been validated when catalytic incineration is used as an emission control method. ESL Technical Report 90-21 is in three volumes. The first volume is a complete literature review of previous Soil venting research and field work. Volume II is a guidance manual which provides important design information and describes methods of pilot testing this technology prior to full-scale application. Results of the Hill AFB test are included in Volume III. These publications will provide invaluable information to Air Force engineers responsible for cleaning up chemically contaminated sites.
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In Situ Soil Venting - Full Scale Test Hill AFB, Guidance Document, Literature Review. Volume 1
1991Co-Authors: D W Depao, S.e. Herbes, J H Wilson, J E Herbes, D K SolomonAbstract:Abstract : The purpose of this project was to demonstrate a full-scale in Situ Soil venting technology and to carefully document the design, operation and performance of this system so that it could be applied at other Air Force contaminated sites. Although this technology is now commercially available, its ability to fully remediate jet fuel spills had never been proven, nor had the full-scale costs ever been validated when catalytic incineration is used as an emission control method. ESL Technical Report 90-21 is in three volumes. The first volume is a complete literature review of previous Soil venting research and field work. Volume II is a guidance manual which provides important design information and describes methods of pilot testing this technology prior to full-scale application. Results of the Hill AFB test are included in Volume III. These publications will provide invaluable information to Air Force engineers responsible for cleaning up chemically contaminated sites.
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In Situ Soil Venting - Full Scale Test, Hill AFB. Volume 3. Guidance Document, Literature Review
1991Co-Authors: D.w. Depaoli, S.e. Herbes, J H Wilson, D K Solomon, H L JenningsAbstract:Abstract : The purpose of this project was to demonstrate a full-scale in Situ Soil venting technology and to carefully document the design, operation and performance of this system so that it could be applied at other Air Force contaminated sites. Although this technology is now commercially available, its ability to fully remediate jet fuel spills had never been proven, nor had the full-scale costs ever been validated when catalytic incineration is used as an emission control method. ESL Technical Report 90-21 is in three volumes. The first volume is a complete literature review of previous Soil venting research and field work. Volume II is a guidance manual which provides important design information and describes methods of pilot testing this technology prior to full-scale application. Results of the Hill AFB test are included in Volume III. These publications will provide invaluable information to Air Force engineers responsible for cleaning up chemically contaminated sites.... Soil venting, Fuel spill remediation, Bioremediation, Vacuum extraction.
Wouter Dorigo - One of the best experts on this subject based on the ideXlab platform.
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characterizing coarse scale representativeness of in Situ Soil moisture measurements from the international Soil moisture network
Vadose Zone Journal, 2013Co-Authors: Alexander Gruber, Angelika Xaver, Simon Zwieback, Wouter Dorigo, W. WagnerAbstract:In Situ Soil moisture measurements play a key role for a variety of large-scale applications. A deep understanding of their quality, especially in terms of spatial representativeness, is crucial for reliably using them as reference data. This study assesses random errors in the coarse-scale representation of in Situ Soil moisture measurements from more than 1400 globally distributed stations, drawn from the International Soil Moisture Network (ISMN), using the triple collocation method. The method was applied on the original measurements as well as on Soil moisture anomalies. Error estimates were summarized for different networks, depths, and measurement principles and furthermore related to the respective climate class, Soil type, average Soil moisture condition, and Soil moisture variability to find possible relationships between measurement errors and local properties. The average network error varies from about 0.02 to 0.06 m 3 m −3 with generally increasing error variability with increasing average error. Trends of (i) decreasing errors with increasing measurement depth and of (ii) increasing errors with increasing average Soil moisture conditions and Soil moisture variability were found for most networks and sensor types. The errors when looking into anomalies are in general lower than for absolute values. No statistically reliable trends for climate- and Soil texture classes were found. These results highlighted the necessity of developing a comprehensive quality control process for in Situ measurements to reliably exploit existing data sets and to select representative sites and sensors most appropriate for the requirements of a particular larger-scale application.
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Characterizing Coarse‐Scale Representativeness of in Situ Soil Moisture Measurements from the International Soil Moisture Network
Vadose Zone Journal, 2013Co-Authors: Alexander Gruber, Angelika Xaver, Simon Zwieback, Wouter Dorigo, W. WagnerAbstract:In Situ Soil moisture measurements play a key role for a variety of large-scale applications. A deep understanding of their quality, especially in terms of spatial representativeness, is crucial for reliably using them as reference data. This study assesses random errors in the coarse-scale representation of in Situ Soil moisture measurements from more than 1400 globally distributed stations, drawn from the International Soil Moisture Network (ISMN), using the triple collocation method. The method was applied on the original measurements as well as on Soil moisture anomalies. Error estimates were summarized for different networks, depths, and measurement principles and furthermore related to the respective climate class, Soil type, average Soil moisture condition, and Soil moisture variability to find possible relationships between measurement errors and local properties. The average network error varies from about 0.02 to 0.06 m 3 m −3 with generally increasing error variability with increasing average error. Trends of (i) decreasing errors with increasing measurement depth and of (ii) increasing errors with increasing average Soil moisture conditions and Soil moisture variability were found for most networks and sensor types. The errors when looking into anomalies are in general lower than for absolute values. No statistically reliable trends for climate- and Soil texture classes were found. These results highlighted the necessity of developing a comprehensive quality control process for in Situ measurements to reliably exploit existing data sets and to select representative sites and sensors most appropriate for the requirements of a particular larger-scale application.
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The International Soil Moisture Network: a data hosting facility for global in Situ Soil moisture measurements
Hydrology and Earth System Sciences, 2011Co-Authors: Wouter Dorigo, Raimund Hohensinn, Christoph Paulik, Angelika Xaver, Susanne Mecklenburg, Alexander Gruber, Sebastian Hahn, W. Wagner, Matthias Drusch, P. Van OevelenAbstract:Abstract. In Situ measurements of Soil moisture are invaluable for calibrating and validating land surface models and satellite-based Soil moisture retrievals. In addition, long-term time series of in Situ Soil moisture measurements themselves can reveal trends in the water cycle related to climate or land cover change. Nevertheless, on a worldwide basis the number of meteorological networks and stations measuring Soil moisture, in particular on a continuous basis, is still limited and the data they provide lack standardization of technique and protocol. To overcome many of these limitations, the International Soil Moisture Network (ISMN; http://www.ipf.tuwien.ac.at/inSitu ) was initiated to serve as a centralized data hosting facility where globally available in Situ Soil moisture measurements from operational networks and validation campaigns are collected, harmonized, and made available to users. Data collecting networks share their Soil moisture datasets with the ISMN on a voluntary and no-cost basis. Incoming Soil moisture data are automatically transformed into common volumetric Soil moisture units and checked for outliers and implausible values. Apart from Soil water measurements from different depths, important metadata and meteorological variables (e.g., precipitation and Soil temperature) are stored in the database. These will assist the user in correctly interpreting the Soil moisture data. The database is queried through a graphical user interface while output of data selected for download is provided according to common standards for data and metadata. Currently (status May 2011), the ISMN contains data of 19 networks and more than 500 stations located in North America, Europe, Asia, and Australia. The time period spanned by the entire database runs from 1952 until the present, although most datasets have originated during the last decade. The database is rapidly expanding, which means that both the number of stations and the time period covered by the existing stations are still growing. Hence, it will become an increasingly important resource for validating and improving satellite-derived Soil moisture products and studying climate related trends. As the ISMN is animated by the scientific community itself, we invite potential networks to enrich the collection by sharing their in Situ Soil moisture data.
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The International Soil Moisture Network: a data hosting facility for global in Situ Soil moisture measurements
Hydrology and Earth System Sciences Discussions, 2011Co-Authors: Wouter Dorigo, Raimund Hohensinn, Christoph Paulik, Susanne Mecklenburg, P Van Oevelen, Sebastian Hahn, W. Wagner, Alan Robock, Matthias Drusch, T. JacksonAbstract:Abstract. In Situ measurements of Soil moisture are invaluable for calibrating and validating land surface models and satellite-based Soil moisture retrievals. In addition, long-term time series of in Situ Soil moisture measurements themselves can reveal trends in the water cycle related to climate or land cover change. Nevertheless, on a worldwide basis the number of meteorological networks and stations measuring Soil moisture, in particular on a continuous basis, is still limited and the data they provide lack standardization of technique and protocol. To overcome many of these limitations, the International Soil Moisture Network (ISMN; http://www.ipf.tuwien.ac.at/inSitu) was initiated to serve as a centralized data hosting facility where globally available in Situ Soil moisture measurements from operational networks and validation campaigns are collected, harmonized, and made available to users. Data collecting networks share their Soil moisture datasets with the ISMN on a voluntary and no-cost basis. Incoming Soil moisture data are automatically transformed into common volumetric Soil moisture units and checked for outliers and implausible values. Apart from Soil water measurements from different depths, important metadata and meteorological variables (e.g., precipitation and Soil temperature) are stored in the database. These will assist the user in correctly interpreting the Soil moisture data. The database is queried through a graphical user interface while output of data selected for download is provided according to common standards for data and metadata. Currently (status January 2011), the ISMN contains data of 16 networks and more than 500 stations located in the North America, Europe, Asia, and Australia. The time period spanned by the entire database runs from 1952 until the present, although most datasets have originated during the last decade. The database is rapidly expanding, which means that both the number of stations and the time period covered by the existing stations are still growing. Hence, it will become an increasingly important resource for validating and improving satellite-derived Soil moisture products and studying climate related trends. As the ISMN is animated by the scientific community itself, we invite potential networks to enrich the collection by sharing their in Situ Soil moisture data.
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The International Soil Moisture Network – A data hosting facility for in Situ Soil moisture measurements in support of SMOS cal/val
2010Co-Authors: Wouter DorigoAbstract:In Situ Soil moisture observations are crucial for validating SMOS and other satellite based Soil moisture products. In order to support valid conclusions about the accuracy of such products the in Situ Soil moisture observations used need to be available for many locations worldwide and have to be intercomparable. So far, the latter requirement is usually not met as the different locally and regionally operating networks apply neither a standard measurement technique nor a standard protocol.
