scholarly journals Modelling Dissolved Phosphorus Losses from Accumulated Soil Phosphorus and Applied Fertilizer and Manure for a National Risk Indicator

2021 ◽  
Author(s):  
Keith Reid ◽  
Kimberley D. Schneider
Keyword(s):  
Soil Phosphorus ◽  
Field Measurements ◽  
The United States ◽  
Accurate Estimation ◽  
Risk Indicator ◽  
Runoff Water ◽  
Dissolved Phosphorus ◽  
P Loss ◽  
P Accumulation ◽  
Phosphorus Losses

Balancing the weighting of various components of phosphorus loss in models is a critical but often overlooked step in accurate estimation of risk of P loss under field conditions. This study compared the P loss coefficients used to predict dissolved P losses from desorption from accumulated P in the soil, and those incidental to applications of P as fertilizer or manure, with extraction coefficients determined from actual P losses reported in literature for sites in Canada, with the addition of some sites with similar soils and climate from the northern tier of the United States. The extraction coefficients for dissolved P measured in runoff water was greater by a factor of 6.5X in year-round edge-of-field measurements than in runoff boxes, indicating that models using P extraction coefficients derived from runoff box experiments will be underestimating the magnitude of losses from P accumulation in soil. Differences among the measurement methods (runoff box, rainfall simulator or edge-of-field) were not evident for incidental losses from applied P, but current models appear to over-predict the losses of applied P. Good fit between measured and modelled DP concentrations were achieved by applying coefficients of 0.275 to the fertilizer equations, and 0.219 to the manure equations, implying that 72.5% of fertilizer P and 78% of manure P are not available for runoff. This study underlines the importance of considering the relative weights of the various components of P loss as new models are developed and validated.

scholarly journals Linking Soil Phosphorus to Dissolved Phosphorus Losses in the Midwest

ael ◽  
2017 ◽  
Vol 2 (1) ◽  
pp. 170004 ◽  
Author(s):  
Emily W. Duncan ◽  
Kevin W. King ◽  
Mark R. Williams ◽  
Greg LaBarge ◽  
Lindsay A. Pease ◽  
...  
Keyword(s):  
Soil Phosphorus ◽  
Dissolved Phosphorus ◽  
Phosphorus Losses

Using Soil Phosphorus Measurements to Assess the Effectiveness of Subsurface-Band Application of Broiler Litter in Reducing Phosphorus Leaching

2018 ◽  
Vol 61 (1) ◽  
pp. 133-138 ◽  
Author(s):  
Jasmeet Lamba ◽  
Puneet Srivastava ◽  
Subhasis Mitra ◽  
Thomas R. Way
Keyword(s):  
Water Quality ◽  
Surface Waters ◽  
Nutrient Management ◽  
Soil Phosphorus ◽  
Agricultural Landscapes ◽  
Runoff Water ◽  
Broiler Litter ◽  
P Loss ◽  
Subsurface Flows ◽  
P Leaching

Abstract. Excessive delivery of phosphorus (P) from agricultural landscapes to surface waters results in water quality impairment. The method of application of broiler litter to agricultural fields significantly affects P loss to surface waters via surface and subsurface flow pathways from agricultural landscapes. Subsurface-band application of broiler litter can help reduce P loss in surface and subsurface flows. Typically, leachate samples are collected using lysimeters or subsurface flows are sampled to assess the effectiveness of subsurface-band application of broiler litter in limiting P mobility. In this study, we tested a simple and inexpensive method of assessing effectiveness of subsurface-band application of broiler litter using ortho-P (PO4-P) measurements in soils. This method of measuring PO4-P concentration in soils showed that subsurface-band application of broiler litter helps to reduce P leaching, whereas surface application of broiler litter was not effective in reducing P leaching. The results of this study show that soil PO4-P measurements can be successfully used to assess the effectiveness of subsurface-band application of broiler litter in reducing P leaching. Keywords: Leachate, Manure, Nutrient management, Phosphorus, Surface runoff, Water quality.

scholarly journals Gypsum amendment as a means to reduce agricultural phosphorus loading: an economic appraisal

2012 ◽  
Vol 21 (3) ◽  
pp. 307-324 ◽  
Author(s):  
Antti Iho ◽  
Marita Laukkanen
Keyword(s):  
Soil Phosphorus ◽  
Threshold Level ◽  
Economic Feasibility ◽  
Mitigation Measures ◽  
Phosphorus Loading ◽  
Phosphorus Fertilization ◽  
Soil Test ◽  
Dissolved Phosphorus ◽  
Soil Test Phosphorus ◽  
Phosphorus Losses

This study analyzes the economic feasibility of gypsum amendment as a means to reduce particulate and dissolved phosphorus loads from arable areas. To this end, an optimization model is developed that includes gypsum amendment as well as matching phosphorus fertilization to crop need and the level of soil phosphorus reserves as phosphorus load mitigation measures, with soil phosphorus reserves measured by soil test phosphorus (STP). The optimal extent of gypsum amendment is then determined simultaneously with optimal fertilization use as a function of field STP level. The results indicate that whether or not gypsum amendment is economically feasible depends on field erosion susceptibility and STP level. When accounting for the costs and benefits to the society on the whole, gypsum treatment suits best to mitigation of phosphorus losses from soils with excessively high phosphorus reserves; once a threshold STP level is reached, gypsum amendment is optimally given up. This threshold level depends on field slope and on society’s willingness to pay for water quality.

Modular Bridge Expansion Joints for Lacey V. Murrow Floating Bridge

1997 ◽  
Vol 1594 (1) ◽  
pp. 163-171 ◽  
Author(s):  
John A. Van Lund ◽  
Mark R. Kaczinski ◽  
Robert J. Dexter
Keyword(s):  
Fatigue Strength ◽  
Fatigue Cracking ◽  
Field Measurements ◽  
The United States ◽  
Limit States ◽  
Expansion Joints ◽  
Lake Washington ◽  
Floating Bridge ◽  
Modular Bridge Expansion Joints ◽  
Washington State Department

The Lacey V. Murrow Bridge (LVM Bridge) is a 2013-m-long floating bridge on Interstate 90 across Lake Washington in Seattle, Washington. Single-support-bar, swivel-joist modular bridge expansion joint systems are located at each end of the bridge between the shore approach spans and the floating pontoons. These joints were designed for 960 mm of longitudinal movement as well as horizontal and vertical rotations caused by wind, wave, temperature, and changes in lake level elevation. A similar joint in an adjacent floating bridge had experienced premature fatigue cracking at welded attachment details because of low fatigue strength. For the LVM Bridge the joint components were fatigue tested and designed by using fatigue limit-states loads, resulting in welded attachment details with improved fatigue strength. In addition, a stiffer center beam and reduced center-beam span lengths produced lower fatigue stress ranges. Joint movements and rotations, fatigue design methodology, results of dynamic analyses, field measurements of the dynamic response, and construction details are described. The total cost of the LVM joints was 1 percent of the final bridge cost. The Washington State Department of Transportation required a 5-year guarantee for the LVM joints. These are the largest modular bridge expansion joints in the United States to be tested and designed for fatigue.

Ultrasonic Imaging of a Crack Using Modified Time Reversal

2016 ◽  
Vol 846 ◽  
pp. 553-558
Author(s):  
Jed Guinto ◽  
Philippe Blanloeuil ◽  
Chun H. Wang ◽  
Francis Rose ◽  
Martin Veidt
Keyword(s):  
Time Reversal ◽  
Computational Simulation ◽  
Field Measurements ◽  
Tone Burst ◽  
Data Matrix ◽  
Accurate Estimation ◽  
Diffraction Tomography ◽  
Static Data ◽  
Reconstruction Quality ◽  
Scatter Field

A majority of the research in Structural Health Monitoring focuses on detection of damage. This paper presents a method of imaging crack damage in an isotropic material using the Time Reversal imaging algorithm. Inputs for the algorithm are obtained via computational simulation of the propagation field of a crack in a medium under tone-burst excitation. The approach is similar to existing techniques such as Diffraction Tomography which makes use of the multi-static data matrix constructed using scatter field measurements from the computational simulation. Results indicate excellent reconstruction quality and accurate estimation of damage size.

scholarly journals Using a One-Dimensional Convolutional Neural Network on Visible and Near-Infrared Spectroscopy to Improve Soil Phosphorus Prediction in Madagascar

2021 ◽  
Vol 13 (8) ◽  
pp. 1519
Author(s):  
Kensuke Kawamura ◽  
Tomohiro Nishigaki ◽  
Andry Andriamananjara ◽  
Hobimiarantsoa Rakotonindrina ◽  
Yasuhiro Tsujimoto ◽  
...  
Keyword(s):  
Neural Network ◽  
Convolutional Neural Network ◽  
Near Infrared ◽  
Soil Phosphorus ◽  
Predictive Ability ◽  
Available P ◽  
Accurate Estimation ◽  
One Dimensional ◽  
P Content ◽  
Soil Available P

As a proximal soil sensing technique, laboratory visible and near-infrared (Vis-NIR) spectroscopy is a promising tool for the quantitative estimation of soil properties. However, there remain challenges for predicting soil phosphorus (P) content and availability, which requires a reliable model applicable for different land-use systems to upscale. Recently, a one-dimensional convolutional neural network (1D-CNN) corresponding to the spectral information of soil was developed to considerably improve the accuracy of soil property predictions. The present study investigated the predictive ability of a 1D-CNN model to estimate soil available P (oxalate-extractable P; Pox) content in soils by comparing it with partial least squares (PLS) and random forest (RF) regressions using soil samples (n = 318) collected from natural (forest and non-forest) and cultivated (upland and flooded rice fields) systems in Madagascar. Overall, the 1D-CNN model showed the best predictive accuracy (R2 = 0.878) with a highly accurate prediction ability (ratio of performance to the interquartile range = 2.492). Compared to the PLS model, the RF and 1D-CNN models indicated 4.37% and 23.77% relative improvement in root mean squared error values, respectively. Based on a sensitivity analysis, the important wavebands for predicting soil Pox were associated with iron (Fe) oxide, organic matter (OM), and water absorption, which were previously known wavelength regions for estimating P in soil. These results suggest that 1D-CNN corresponding spectral signatures can be expected to significantly improve the predictive ability for estimating soil available P (Pox) from Vis-NIR spectral data. Rapid and accurate estimation of available P content in soils using our results can be expected to contribute to effective fertilizer management in agriculture and the sustainable management of ecosystems. However, the 1D-CNN model will require a large dataset to extend its applicability to other regions of Madagascar. Thus, further updates should be tested in future studies using larger datasets from a wide range of ecosystems in the tropics.

scholarly journals Revised Method and Outcomes for Estimating Soil Phosphorus Losses from Agricultural Land in the Chesapeake Bay Watershed Model

2017 ◽  
Vol 46 (6) ◽  
pp. 1388-1394 ◽  
Author(s):  
Alisha Spears Mulkey ◽  
Frank J. Coale ◽  
Peter A. Vadas ◽  
Gary W. Shenk ◽  
Gopal X. Bhatt
Keyword(s):  
Chesapeake Bay ◽  
Agricultural Land ◽  
Soil Phosphorus ◽  
Watershed Model ◽  
Chesapeake Bay Watershed ◽  
Phosphorus Losses

The wildland - urban interface fire problem - current approaches and research needs

2010 ◽  
Vol 19 (2) ◽  
pp. 238 ◽  
Author(s):  
William E. Mell ◽  
Samuel L. Manzello ◽  
Alexander Maranghides ◽  
David Butry ◽  
Ronald G. Rehm
Keyword(s):  
Wildland Fire ◽  
Fire Suppression ◽  
Economic Cost ◽  
Field Measurements ◽  
The United States ◽  
Test Methods ◽  
Wildland Urban Interface ◽  
Fuel Treatment ◽  
Treatment Techniques ◽  
Exposure Conditions

Wildfires that spread into wildland–urban interface (WUI) communities present significant challenges on several fronts. In the United States, the WUI accounts for a significant portion of wildland fire suppression and wildland fuel treatment costs. Methods to reduce structure losses are focussed on fuel treatments in either wildland fuels or residential fuels. There is a need for a well-characterised, systematic testing of these approaches across a range of community and structure types and fire conditions. Laboratory experiments, field measurements and fire behaviour models can be used to better determine the exposure conditions faced by communities and structures. The outcome of such an effort would be proven fuel treatment techniques for wildland and residential fuels, risk assessment strategies, economic cost analysis models, and test methods with representative exposure conditions for fire-resistant building designs and materials.

scholarly journals High concentrations of coarse particles emitted from a cattle feeding operation

2011 ◽  
Vol 11 (16) ◽  
pp. 8809-8823 ◽  
Author(s):  
N. Hiranuma ◽  
S. D. Brooks ◽  
J. Gramann ◽  
B. W. Auvermann
Keyword(s):  
United States ◽  
Particulate Matter ◽  
Chemical Properties ◽  
Field Measurements ◽  
The United States ◽  
Water Soluble ◽  
Size Distributions ◽  
Cattle Feeding ◽  
High Concentrations ◽  
Organic Particles

Abstract. Housing roughly 10 million head of cattle in the United States alone, open air cattle feedlots represent a significant but poorly constrained source of atmospheric particles. Here we present a comprehensive characterization of physical and chemical properties of particles emitted from a large representative cattle feedlot in the Southwest United States. In the summer of 2008, measurements and samplings were conducted at the upwind and downwind edges of the facility. A series of far-field measurements and samplings was also conducted 3.5 km north of the facility. Two instruments, a GRIMM Sequential Mobility Particle Sizer (SMPS) and a GRIMM Portable Aerosol Spectrometer (PAS), were used to measure particle size distributions over the range of 0.01 to 25 μm diameter. Raman microspectroscopy was used to determine the chemical composition of particles on a single particle basis. Volume size distributions of dust were dominated by coarse mode particles. Twenty-four hour averaged concentrations of PM10 (particulate matter with a diameter of 10 μm or less) were as high as 1200 μg m−3 during the campaign. The primary constituents of the particulate matter were carbonaceous materials, such as humic acid, water soluble organics, and less soluble fatty acids, including stearic acid and tristearin. A significant fraction of the organic particles was present in internal mixtures with salts. Basic characteristics such as size distribution and composition of agricultural aerosols were found to be different than the properties of those found in urban and semi-urban aerosols. Failing to account for such differences may lead to errors in estimates of aerosol effects on local air quality, visibility, and public health.

Leaching of dissolved phosphorus from tile-drained agricultural areas

2016 ◽  
Vol 73 (12) ◽  
pp. 2953-2958 ◽  
Author(s):  
H. E. Andersen ◽  
J. Windolf ◽  
B. Kronvang
Keyword(s):  
Soil Layer ◽  
High Concentration ◽  
Measured Concentration ◽  
Leaching Potential ◽  
Dissolved Phosphorus ◽  
Olsen P ◽  
P Loss ◽  
Tile Drains ◽  
Extractable P ◽  
Water Extractable

Abstract We investigated leaching of dissolved phosphorus (P) from 45 tile-drains representing animal husbandry farms in all regions of Denmark. Leaching of P via tile-drains exhibits a high degree of spatial heterogeneity with a low concentration in the majority of tile-drains and few tile-drains (15% in our investigation) having high to very high concentration of dissolved P. The share of dissolved organic P (DOP) was high (up to 96%). Leaching of DOP has hitherto been a somewhat overlooked P loss pathway in Danish soils and the mechanisms of mobilization and transport of DOP needs more investigation. We found a high correlation between Olsen-P and water extractable P. Water extractable P is regarded as an indicator of risk of loss of dissolved P. Our findings indicate that Olsen-P, which is measured routinely in Danish agricultural soils, may be a useful proxy for the P leaching potential of soils. However, we found no straight-forward correlation between leaching potential of the top soil layer (expressed as either degree of P saturation, Olsen-P or water extractable P) and the measured concentration of dissolved P in the tile-drain. This underlines that not only the source of P but also the P loss pathway must be taken into account when evaluating the risk of P loss.

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