TY - JOUR TI - The hydraulic conductivity structure of gravel-dominated vadose zones within alluvial floodplains AU - Miller, Ronald B. AU - Heeren, Derek M. AU - Fox, Garey A. AU - Halihan, Todd AU - Storm, Daniel E. AU - Mittelstet, Aaron R. T2 - Journal of Hydrology AB - The floodplains of many gravel-bed streams have a general stratigraphy that consists of a layer of topsoil covering gravel-dominated subsoil. Previous research has demonstrated that this stratigraphy can facilitate preferential groundwater flow through focused linear features, such as paleochannels, or gravelly regions within the vadose zone. These areas within the floodplain vadose zone may provide a route for interactions between the floodplain surface and alluvial groundwater, effectively extending the hyporheic zone across the floodplain during high stream stage. The objective of this research was to assess the structure and scale of texture heterogeneity within the vadose zone within the gravel subsoils of alluvial floodplains using resistivity data combined with hydraulic testing and sediment sampling of the vadose zone. Point-scale and broad-scale methodologies in combination can help us understand spatial heterogeneity in hydraulic conductivity without the need for a large number of invasive hydraulic tests. The evaluated sites in the Ozark region of the United States were selected due to previous investigations indicating that significant high conductivity flow zones existed in a matrix which include almost no clay content. Data indicated that resistivity corresponded with the fine content in the vadose zone and subsequently corresponds to the saturated hydraulic conductivity. Statistical analysis of resistivity data, and supported by data from the soil sampling and permeameter hydraulic testing, identified isolated high flow regions and zones that can be characterized as broad-scale high hydraulic conductivity features with potentially significant consequences for the migration of water and solutes and therefore are of biogeochemical and ecological significance. DA - 2014/5// PY - 2014/5// DO - 10.1016/j.jhydrol.2014.03.046 VL - 513 SP - 229-240 J2 - Journal of Hydrology LA - en OP - SN - 0022-1694 UR - http://dx.doi.org/10.1016/j.jhydrol.2014.03.046 DB - Crossref KW - Electrical resistivity imaging KW - Floodplain KW - Gravel KW - Hydraulic conductivity KW - Permeameter KW - Vadose zone ER - TY - JOUR TI - Quantifying the erodibility of streambanks and hillslopes due to surface and subsurface forces AU - Al-Madhhachi, A.T. AU - Fox, G.A. AU - Hanson, G.J. T2 - Transactions of the ASABE AB - Abstract. The erosion rate of cohesive soils due to fluvial forces is usually computed using an excess shear stress model. However, no mechanistic approaches are available for incorporating additional forces, such as seepage, into the excess shear stress model parameters. Recent research incorporated subsurface (seepage) forces into a mechanistic detachment rate model for streambeds. The new detachment model, the Modified Wilson model, was based on two modified dimensional parameters (b0 and b1) that included seepage forces. The objective of this study was to modify the parameters (b0 and b1) to quantify the influence of seepage on erodibility of cohesive streambanks and to compare the results to those obtained from tests on horizontal beds. A new miniature version of a submerged jet erosion test device (“mini” JET) and a seepage column were utilized to derive the parameters of the Modified Wilson model for a silty sand soil and a clayey sand soil across a range of uniform seepage gradients. The experimental setup was intended to mimic a streambed and a streambank when the “mini” JET and seepage column were placed in vertical and horizontal orientations, respectively. The soils were packed in a standard mold at a uniform bulk density (1.5 to 1.6 Mg m-3) near the optimum water content. Seepage forces influenced the observed erosion with a non-uniform influence on b0 and b1 as functions of the hydraulic gradient and density. Expected theoretical differences between Wilson model parameters for streambanks and streambeds were not consistently observed for these erodible soils, most likely due to variability in streambed and streambank samples in terms of soil preparation, packing, and seepage gradient establishment. The influence of seepage forces can be predicted by the Modified Wilson model parameters in both vertical and horizontal experimental setups using JETs on soils without seepage. Additional research is needed on the behavior of several mechanistic soil parameters under the influence of seepage. DA - 2014/// PY - 2014/// DO - 10.13031/trans.57.10416 VL - 57 IS - 1 SP - 1057-1069 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84988589120&partnerID=MN8TOARS ER - TY - JOUR TI - Mechanistic Detachment Rate Model to Predict Soil Erodibility Due to Fluvial and Seepage Forces AU - Al-Madhhachi, A. T. AU - Fox, G. A. AU - Hanson, G. J. AU - Tyagi, A. K. AU - Bulut, R. T2 - Journal of Hydraulic Engineering AB - The erosion rate of cohesive soils is typically computed using an excess shear stress model based on the applied fluvial shear stress. However, no mechanistic approaches are available for incorporating additional forces, such as groundwater seepage into the excess shear stress model parameters. Seepage forces are known to be significant contributors to streambank erosion and failure. The objective of this research was to incorporate seepage forces into a mechanistic fundamental detachment rate model to improve the predictions of the erosion rate of cohesive soils. The new detachment model, which is referred to as the modified Wilson model, was based on two modified dimensional soil parameters (b0 and b1) that included seepage forces due to localized groundwater flow. The proposed model provided a general framework for studying the impact of soil properties, fluid characteristics, and seepage forces on cohesive soil erodibility. Equations were presented for deriving the material parameters from both flume experiments and jet erosion tests (JETs). In order to investigate the influence of seepage on erodibility, the erodibility of two cohesive soils (silty sand and clayey sand) was measured in flume tests and with a new miniature version of the JET device (mini JET). The soils were packed in three equal lifts in a standard mold (for JETs) and in a soil box (for flume tests) at a uniform bulk density (1.5 and 1.6 Mg/m3) near the soil’s optimum water content. A seepage column was utilized to induce a constant hydraulic gradient on the soils tested in the flume and with the mini JET. The modified Wilson model parameters, b0 and b1, were derived from the erosion rate data both with and without the influence of seepage from the flume and JETs. Seepage forces had a significant but nonuniform influence on the derived b0 and b1 as functions of the hydraulic gradient and soil density. The more fundamental detachment model can be used in place of the excess shear stress model with parameters that can be derived using JETs, transforming the modeling of cohesive soils for hillslopes, embankments, gullies, streambeds, and streambanks. DA - 2014/5// PY - 2014/5// DO - 10.1061/(ASCE)HY.1943-7900.0000836 VL - 140 IS - 5 SP - 04014010 J2 - J. Hydraul. Eng. LA - en OP - SN - 0733-9429 1943-7900 UR - http://dx.doi.org/10.1061/(ASCE)HY.1943-7900.0000836 DB - Crossref KW - Seepage KW - Detachment rate model KW - Cohesive soils KW - Flume KW - Jet erosion test ER - TY - JOUR TI - Validation of a Quantitative Phosphorus Loss Assessment Tool AU - White, Michael J. AU - Storm, Daniel E. AU - Smolen, Michael D. AU - Busteed, Philip R. AU - Zhang, Hailin AU - Fox, Garey A. T2 - Journal of Environmental Quality AB - Pasture Phosphorus Management Plus (PPM Plus) is a tool that allows nutrient management and conservation planners to evaluate phosphorus (P) loss from agricultural fields. This tool uses a modified version of the widely used Soil and Water Assessment Tool model with a vastly simplified interface. The development of PPM Plus has been fully described in previous publications; in this article we evaluate the accuracy of PPM Plus using 286 field-years of runoff, sediment, and P validation data from runoff studies at various locations in Oklahoma, Texas, Arkansas, and Georgia. Land uses include pasture, small grains, and row crops with rainfall ranging from 630 to 1390 mm yr, with and without animal manure application. PPM Plus explained 68% of the variability in total P loss, 56% of runoff, and 73% of the variability of sediment yield. An empirical model developed from these data using soil test P, total applied P, slope, and precipitation only accounted for 15% of the variability in total P loss, which implies that a process-based model is required to account for the diversity present in these data. PPM Plus is an easy-to-use conservation planning tool for P loss prediction, which, with modification, could be applicable at the regional and national scales. DA - 2014/1// PY - 2014/1// DO - 10.2134/jeq2011.0434 VL - 43 IS - 1 SP - 224-234 J2 - J. Environ. Qual. LA - en OP - SN - 0047-2425 UR - http://dx.doi.org/10.2134/jeq2011.0434 DB - Crossref ER - TY - CONF TI - Linking freshmen and senior engineering design teams: Engaging early academic career students in engineering design AU - Fox, G.A. AU - Weckler, P.R. AU - Thomas, D.L. C2 - 2014/// C3 - American Society of Agricultural and Biological Engineers Annual International Meeting 2014, ASABE 2014 DA - 2014/// VL - 1 SP - 435-442 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84911864784&partnerID=MN8TOARS ER - TY - CONF TI - Use of EPS block geofoam with internal drainage for sandy slopes subjected to seepage flow AU - Akay, O. AU - Özer, A.T. AU - Fox, G.A. C2 - 2014/// C3 - 10th International Conference on Geosynthetics, ICG 2014 DA - 2014/// UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84924942335&partnerID=MN8TOARS ER - TY - JOUR TI - Estimating sediment and phosphorus loads from streambanks with and without riparian protection AU - Miller, Ronald B. AU - Fox, Garey A. AU - Penn, Chad J. AU - Wilson, Stuart AU - Parnell, Abigail AU - Purvis, Rebecca A. AU - Criswell, Kelsey T2 - Agriculture, Ecosystems & Environment AB - In some watersheds, the majority of the total sediment load to streams and rivers is from streambanks, but insufficient data exist on actual loading from this source and the potential protective effect of riparian protection in many watersheds. Using aerial imagery, video reconnaissance for unstable banks, and streambank phosphorus (P) sampling, this research studied streambanks throughout the Barren Fork Creek (BFC) watershed within Oklahoma to address four major objectives: (i) quantify the amount of streambank erosion and failure throughout the watershed, (ii) quantify the magnitude and the intra-site and inter-site spatial variability in streambank soil chemistry, water soluble phosphorus (WSP), and total phosphorus (TP), (iii) quantify the load of WSP and TP from streambanks in the watershed, and (iv) estimate the benefit of riparian management practices. Ten streambank study sites were selected on BFC, including seven sites with existing or historic riparian forest (historically protected, HP), and three with no riparian forest (historically unprotected, HUP). Median and mean streambank migration rates were 9.5 and 17.5 m for the HP sites compared to 37.6 and 49.2 m for the three HUP sites over the seven year period. Total WSP from streambanks on BFC from unprotected and failing banks was approximately 1.2 × 103 kg yr−1, which represented approximately 10% of the dissolved P load estimated from USGS gauges on BFC. The estimated TP load was approximately 9.0 × 104 kg TP yr−1, which exceeded the TP load estimated from gauge data, although TP is largely sediment-bound and thus subject to sediment transport dynamics such as floodplain deposition. Streambanks represented a considerable source of P, and riparian forest sites showed significantly lower rates of retreat. The methodology of using detailed P characterization, lateral retreat rates from aerial photography, and video reconnaissance to characterize bank stability was an effective approach for assessing the WSP and TP load contribution from streambanks. DA - 2014/5// PY - 2014/5// DO - 10.1016/j.agee.2014.03.016 VL - 189 SP - 70-81 J2 - Agriculture, Ecosystems & Environment LA - en OP - SN - 0167-8809 UR - http://dx.doi.org/10.1016/j.agee.2014.03.016 DB - Crossref KW - Degree of phosphorus saturation KW - Riparian vegetation KW - Sediment KW - Streambank KW - Total phosphorus KW - Water soluble phosphorus ER - TY - JOUR TI - Laboratory soil piping and internal erosion experiments: Evaluation of a soil piping model for low-compacted soils AU - Fox, G.A. AU - Felice, R.G. AU - Midgley, T.L. AU - Wilson, G.V. AU - Al-Madhhachi, A.-S.T. T2 - Earth Surface Processes and Landforms AB - ABSTRACT Mechanistic models have been proposed for soil piping and internal erosion on well‐compacted levees and dams, but limited research has evaluated these models in less compacted (more erodible) soils typical of hillslopes and streambanks. This study utilized a soil box (50 cm long, 50 cm wide and 20 cm tall) to conduct constant‐head, soil pipe and internal erosion experiments for two soils (clay loam from Dry Creek and sandy loam from Cow Creek streambanks) packed at uniform bulk densities. Initial gravimetric moisture contents prior to packing were 10, 12 and 14% for Dry Creek soil and 8, 12, and 14% for Cow Creek soil. A 1‐cm diameter rod was placed horizontally along the length of the soil bed during packing and carefully removed after packing to create a continuous soil pipe. A constant head was maintained at the inflow end. Flow rates and sediment concentrations were measured from the pipe outlet. Replicate submerged jet erosion tests (JETs) were conducted to derive erodibility parameters for repacked samples at the same moisture contents. Flow rates from the box experiments were used to calibrate the mechanistic model. The influence of the initial moisture content was apparent, with some pipes (8% moisture content) expanding so fast that limited data was collected. The mechanistic model was able to estimate equivalent flow rates to those observed in the experiments, but had difficulty matching observed sediment concentrations when the pipes rapidly expanded. The JETs predicted similar erodibility coefficients compared to the mechanistic model for the more erodible cases but not for the less erodible cases (14% moisture content). Improved models are needed that better define the changing soil pipe cross‐section during supply‐ and transport‐limited internal erosion, especially for piping through lower compacted (more erodible) soils as opposed to more well‐compacted soils resulting from constructing levees and dams. Copyright © 2013 John Wiley & Sons, Ltd. DA - 2014/// PY - 2014/// DO - 10.1002/esp.3508 VL - 39 IS - 9 SP - 1137-1145 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84903981934&partnerID=MN8TOARS KW - groundwater seepage KW - internal erosion KW - jet erosion test KW - piping KW - soil erodibility ER - TY - JOUR TI - Berm Method for Quantification of Infiltration at the Plot Scale in High Conductivity Soils AU - Heeren, Derek M. AU - Fox, Garey A. AU - Storm, Daniel E. T2 - Journal of Hydrologic Engineering AB - Measuring infiltration at the plot scale is difficult, especially for high hydraulic conductivity soils. At the plot scale, the infiltration rate is usually calculated by comparing surface runoff to rainfall. Direct measurement of infiltration beyond the point scale is typically limited to locations where land forming (e.g., infiltration pond) has been performed or fields with basin irrigation systems. The standard method for field measurement of point-scale infiltration is the double ring infiltrometer, which is limited in size (typically 30 cm diameter). In this research, a new method is proposed that uses a temporary berm constructed of a water-filled 15-cm diameter vinyl hose with the edges sealed to the soil using bentonite. The berm is capable of confining infiltration plot areas of various sizes (e.g., 1×1 and 3×3 m areas in this research). Water tanks with 0.8 and 4.9 m3 capacity were used to supply water to the plots by gravity flow. A constant head could be maintained within the plot using either an automatic float valve for lower infiltration rates or a manually operated gate valve for higher infiltration rates. Observation wells were installed outside the plots to monitor for water table rise and tracers that leached into the groundwater. Guidelines are provided for tank size and refilling frequency for conducting field experiments. The procedure was tested on soils ranging from silt loam to coarse gravel using 12 1×1 and 3×3 m plots at three alluvial floodplain sites. Measured infiltration rates ranged over two orders of magnitude (0.8–74 cm/h) and were typically greater than the estimated permeability of the limiting layer reported in soil surveys, suggesting the need for larger scale field measurements of infiltration rates. DA - 2014/2// PY - 2014/2// DO - 10.1061/(ASCE)HE.1943-5584.0000802 VL - 19 IS - 2 SP - 457-461 J2 - J. Hydrol. Eng. LA - en OP - SN - 1084-0699 1943-5584 UR - http://dx.doi.org/10.1061/(ASCE)HE.1943-5584.0000802 DB - Crossref KW - Berm KW - Gravel KW - High conductivity soils KW - Infiltration KW - Plot scale ER - TY - JOUR TI - Bank undercutting and tension failure by groundwater seepage: Predicting failure mechanisms AU - Fox, G.A. AU - Felice, R.G. T2 - Earth Surface Processes and Landforms AB - ABSTRACT Groundwater seepage can lead to the erosion and failure of streambanks and hillslopes. Two groundwater instability mechanisms include (i) tension failure due to the seepage force exceeding the soil shear strength or (ii) undercutting by seepage erosion and eventual mass failure. Previous research on these mechanisms has been limited to non‐cohesive and low cohesion soils. This study utilized a constant‐head, seepage soil box packed with more cohesive (6% and 15% clay) sandy loam soils at prescribed bulk densities (1.30 to 1.70 Mg m −3 ) and with a bank angle of 90° to investigate the controls on failure mechanisms due to seepage forces. A dimensionless seepage mechanism (SM) number was derived and evaluated based on the ratio of resistive cohesion forces to the driving forces leading to instability including seepage gradients with an assumed steady‐state seepage angle. Tension failures and undercutting were both observed dependent primarily on the saturated hydraulic conductivity, effective cohesion, and seepage gradient. Also, shapes of seepage undercuts for these more cohesive soils were wider and less deep compared to undercuts in sand and loamy sand soils. Direct shear tests were used to quantify the geotechnical properties of the soils packed at the various bulk densities. The SM number reasonably predicted the seepage failure mechanism (tension failure versus undercutting) based on the geotechnical properties and assumed steady‐state seepage gradients of the physical‐scale laboratory experiments, with some uncertainty due to measurement of geotechnical parameters, assumed seepage gradient direction, and the expected width of the failure block. It is hypothesized that the SM number can be used to evaluate seepage failure mechanisms when a streambank or hillslope experiences steady‐state seepage forces. When prevalent, seepage gradient forces should be considered when analyzing bank stability, and therefore should be incorporated into commonly used stability models. Copyright © 2013 John Wiley & Sons, Ltd. DA - 2014/// PY - 2014/// DO - 10.1002/esp.3481 VL - 39 IS - 6 SP - 758-765 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84898816798&partnerID=MN8TOARS KW - factor of safety KW - undercutting KW - bank failure KW - seepage KW - streambank stability KW - pore-water pressure ER - TY - JOUR TI - Application of Isothermal Calorimetry to Phosphorus Sorption onto Soils in a Flow-through System AU - Penn, Chad AU - Heeren, Derek AU - Fox, Garey AU - Kumar, Ajay T2 - Soil Science Society of America Journal AB - The degree, mechanisms, and kinetics of phosphorus (P) sorption onto soils can have a significant influence on leaching losses of P from soil. The objectives of this study were to measure the impact of retention time (RT) on P sorption in a flow-through system intended to simulate downward movement of a P solution through two different riparian soils, and determine if isothermal titration calorimetry (ITC) can provide useful information reflective of flow-through results. Topsoil from two riparian/alluvial sites (Barren Fork and Clear Creek) was sampled and characterized for P concentrations and parameters related to P sorption. Flow-through P sorption experiments were conducted to examine the effect of RT and inflow P concentration on P sorption; this was compared to results of ITC experiments where the heat of reaction was measured with the addition of P to soils. Results of ITC experiments were reflective of both soil characterization and flow-through sorption in that the Barren Fork soil sorbed less P, but at a faster rate, compared to Clear Creek. Based on thermograms, the dominant P sorption reaction was ligand exchange onto Al/Fe oxides/hydroxides, with a lesser degree of precipitation. Phosphorus removal for both soils was limited by physical nonequilibrium instead of chemical nonequilibrium (sorption kinetics). The calorimetry approach presented can help provide soil-specific information on the risk of P inputs to leaching (degree of P sorption) under different conditions (flow rate or RT), and potential for desorption (P sorption mechanisms). DA - 2014/1// PY - 2014/1// DO - 10.2136/sssaj2013.06.0239 VL - 78 IS - 1 SP - 147-156 J2 - Soil Science Society of America Journal LA - en OP - SN - 0361-5995 UR - http://dx.doi.org/10.2136/sssaj2013.06.0239 DB - Crossref ER - TY - CONF TI - Finite element modeling of long-term phosphorus leaching through macropores in the Ozark ecoregion AU - Freiberger, R.P. AU - Heeren, D.M. AU - Fox, G.A. AU - Penn, C.J. AU - Eisenhauer, D.E. C2 - 2014/// C3 - American Society of Agricultural and Biological Engineers Annual International Meeting 2014, ASABE 2014 DA - 2014/// VL - 3 SP - 1862-1881 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84911473860&partnerID=MN8TOARS ER - TY - CONF TI - Experimental testing of a new algorithm for analysis of vegetative filter strips with shallow water table effects AU - Fox, G.A. AU - Munoz-Carpena, R. AU - Purvis, R.A. C2 - 2014/// C3 - American Society of Agricultural and Biological Engineers Annual International Meeting 2014, ASABE 2014 DA - 2014/// VL - 7 SP - 4934-4945 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84911472062&partnerID=MN8TOARS ER - TY - JOUR TI - Divergence and flow direction as indicators of subsurface heterogeneity and stage-dependent storage in alluvial floodplains AU - Heeren, D.M. AU - Fox, G.A. AU - Fox, A.K. AU - Storm, D.E. AU - Miller, R.B. AU - Mittelstet, A.R. T2 - Hydrological Processes AB - Assuming homogeneity in alluvial aquifers is convenient, but limits our ability to accurately predict stream-aquifer interactions. Research is needed on (i) identifying the presence of focused, as opposed to diffuse, groundwater discharge/recharge to streams and (ii) the magnitude and role of large-scale bank and transient storage in alluvial floodplains relative to changes in stream stage. The objective of this research was to document and quantify the effect of stage-dependent aquifer heterogeneity and bank storage relative to changes in stream stage using groundwater flow divergence and direction. Monitoring was performed in alluvial floodplains adjacent to the Barren Fork Creek and Honey Creek in northeastern Oklahoma. Based on results from subsurface electrical resistivity mapping, observation wells were installed in high and low electrical resistivity subsoils. Water levels in the wells were recorded real time using pressure transducers (August to October 2009). Divergence was used to quantify heterogeneity (i.e. variation in hydraulic conductivity, porosity, and/or aquifer thickness), and flow direction was used to assess the potential for large-scale (100 m) bank or transient storage. Areas of localized heterogeneity appeared to act as divergence zones allowing stream water to quickly enter the groundwater system, or as flow convergence zones draining a large groundwater area. Maximum divergence or convergence occurred with maximum rates of change in flow rates or stream stage. Flow directions in the groundwater changed considerably between base and high flows, suggesting that the floodplains acted as large-scale bank storage zones, rapidly storing and releasing water during passage of a storm hydrograph. During storm events at both sites, the average groundwater direction changed by at least 90° from the average groundwater direction during baseflow. Aquifer heterogeneity in floodplains yields hyporheic flows that are more responsive and spatially and temporally complex than would be expected compared to more common assumptions of homogeneity. Copyright © 2012 John Wiley & Sons, Ltd. DA - 2014/// PY - 2014/// DO - 10.1002/hyp.9674 VL - 28 IS - 3 SP - 1307-1317 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84891737320&partnerID=MN8TOARS KW - alluvial floodplains KW - direction KW - divergence KW - groundwater flow KW - heterogeneity KW - hydraulic gradient ER - TY - JOUR TI - Assessment of EPS block geofoam with internal drainage for sandy slopes subjected to seepage flow AU - Akay, O. AU - Özer, A.T. AU - Fox, G.A. T2 - Geosynthetics International AB - ABSTRACT: Lightweight expanded polystyrene (EPS) block geofoam (geofoam block) is commonly used as a replacement of the heavy in situ soil during slope remediation in order to reduce driving forces. The design procedure requires the use of permanent drainage systems to alleviate hydrostatic pressures in geofoam block slope systems. In this study, small-scale laboratory lysimeter experiments investigated the behavior of a stabilized sandy slope with a geofoam block slope system experiencing seepage. An internal drainage system was incorporated by grooving dual drainage channels (weep holes) on the top and bottom side of the geofoam blocks. A lysimeter with dimensions of 60 cm height, 20 cm width, and 200 cm length was constructed in the laboratory. Slopes were constructed by compacting sand. The geofoam blocks (2.5 cm height, 5 cm width, and 15 cm length) were placed on the sandy slope face with an angle of 45° in ‘one row' and ‘two rows' configurations. The experiments were conducted under constant water pressure heads (25-, 38-, and 50-cm pressure head boundary conditions) in the water reservoir located at the opposite end of the lysimeter from the geofoam blocks. In general, the lightweight geofoam blocks could not resist earth and hydrostatic pressures under seepage. The back-slope was not self-stable under seepage conditions, and deep-seated global stability failures were observed, except for the remediated slope at the 25- and 38-cm pressure head boundary conditions. The internal drainage system was ineffective at dissipating piezometric pressures at the higher seepage gradients investigated at this lysimeter scale. Numerical slope stability modeling confirmed these observations, predicting a factor of safety below the critical value for global stability in cases where failure was observed. More elaborate geofoam block configurations and/or drainage systems should be used to increase resistance against global stability failure caused by higher seepage gradients. DA - 2014/// PY - 2014/// DO - 10.1680/gein.14.00024 VL - 21 IS - 6 SP - 364-376 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84937540677&partnerID=MN8TOARS KW - Geosynthetics KW - Slope stability KW - EPS block geofoam KW - Seepage KW - Internal drainage KW - Stability modeling ER - TY - CONF TI - Bank stability and toe erosion (BSTEM) modeling of bank retreat and riparian tree root protection in composite streambanks AU - Daly, E.R. AU - Miller, R.B. AU - Fox, G.A. C2 - 2014/// C3 - American Society of Agricultural and Biological Engineers Annual International Meeting 2014, ASABE 2014 DA - 2014/// VL - 2 SP - 1232-1249 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84911915179&partnerID=MN8TOARS ER - TY - JOUR TI - A new method for remediation of sandy slopes susceptible to seepage flow using EPS-block geofoam AU - Özer, A.T. AU - Akay, O. AU - Fox, G.A. AU - Bartlett, S.F. AU - Arellano, D. T2 - Geotextiles and Geomembranes AB - Using expanded polystyrene (EPS) geofoam (geofoam block) in slope remediation projects has drawn interest from the civil engineering sector for its ease of application and budget saving features. According to design precedence, all slope remediation applications that use geofoam blocks should incorporate permanent drainage systems to prevent instability of the lightweight geofoam blocks due to hydrostatic and seepage pressures. In this study, a new method for slope remediation using geofoam blocks was tested through physical laboratory experiments. For this purpose, a total of 24 lysimeter (dimensions of 60 cm height, 20 cm width, and 200 cm length) experiments (including duplicates) were conducted in which seepage through a geofoam block slope system were generated with three different constant water levels in the water reservoir of the lysimeter. Geofoam blocks (dimensions of 2.5 cm height, 5 cm width, and 15 cm length) were assembled to form embankment type configuration at the toe section of the sandy slopes. This study also included coupled numerical model simulations that were comprised of variably saturated flow modeling and slope stability modeling which could be implemented successfully for the global static failure analysis of the geofoam block slope system comprised of two mediums with different geotechnical characteristics. In addition to global static stability failure analysis, which involved conventional limit equilibrium analysis for the geofoam block slope system, hydrostatic sliding mechanism was investigated which provided insight into using an overburden concept to increase the resistance against horizontal driving forces. Experimental and numerical modeling results showed that the geofoam block slope system was stable even though the phreatic surface was above the bottom of the geofoam block assemblage. For this reason, the embankment type configuration tested in this study can be considered a viable remediation technique where seepage induced deep-seated global stability and hydrostatic sliding failures are a concern. DA - 2014/// PY - 2014/// DO - 10.1016/j.geotexmem.2014.01.003 VL - 42 IS - 2 SP - 166-180 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84896818124&partnerID=MN8TOARS KW - EPS-block geofoam KW - Slope stability KW - Slope remediation KW - Hydrostatic sliding KW - Seepage ER - TY - CONF TI - Application of a transient storage zone model to soil pipeflow tracer injection experiments AU - Zhou, Y. AU - Wilson, G.V. AU - Fox, G.A. AU - Rigby, J.R. AU - Dabney, S.M. C2 - 2014/// C3 - American Society of Agricultural and Biological Engineers Annual International Meeting 2014, ASABE 2014 DA - 2014/// VL - 1 SP - 423-434 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84911940204&partnerID=MN8TOARS ER - TY - JOUR TI - Predicting Scientific Oral Presentation Scores in a High School Photonics Science, Technology, Engineering and Mathematics (STEM) Program AU - Gilchrist, Pamela Olivia AU - Carpenter, Eric D. AU - Gray-Battle, Asia T2 - 12TH EDUCATION AND TRAINING IN OPTICS AND PHOTONICS CONFERENCE AB - A hybrid teacher professional development, student science technology mathematics and engineering pipeline enrichment program was operated by the reporting research group for the past 3 years. Overall, the program has reached 69 students from 13 counties in North Carolina and 57 teachers from 30 counties spread over a total of five states. Quantitative analysis of oral presentations given by participants at a program event is provided. Scores from multiple raters were averaged and used as a criterion in several regression analyses. Overall it was revealed that student grade point averages, most advanced science course taken, extra quality points earned in their most advanced science course taken, and posttest scores on a pilot research design survey were significant predictors of student oral presentation scores. Rationale for findings, opportunities for future research, and implications for the iterative development of the program are discussed. DA - 2014/// PY - 2014/// DO - 10.1117/12.2070741 VL - 9289 SP - SN - 0277-786X KW - photonics KW - STEM KW - high school KW - regression KW - public speaking ER - TY - JOUR TI - Piloting a Fiber Optics and Electronic Theory Curriculum with High School Students AU - Gilchrist, Pamela Olivia AU - Carpenter, Eric AU - Gray-Battle, Asia T2 - 12TH EDUCATION AND TRAINING IN OPTICS AND PHOTONICS CONFERENCE AB - Previous participants from a multi-year blended learning intervention focusing on science, technology, engineering and mathematics (STEM) content knowledge, technical, college, and career preparatory skills were recruited to pilot a new module designed by the project staff. Participants met for a total of 22 contact hours receiving lectures from staff and two guest speakers from industries relevant to photonics, fiber optics hands-on experimentation, and practice with documenting progress. Activities included constructing a fiber optics communication system, troubleshooting breadboard circuits and diagrammed circuits as well as hypothesis testing to discover various aspects of fiber optic cables. Participants documented their activities, wrote reflections on the content and learning endeavor and gave talks about their research experiences to staff, peers, and relatives during the last session. Overall, it was found that a significant gain in content knowledge occurred between the time of pre-testing (Mean=0.54) and post-testing time points for the fiber optics portion of the curriculum via the use of a paired samples t-test (Mean=0.71), t=-2.72, p<.05. Additionally, the electronic theory test results were not a normal distribution and for this reason non-parametric testing was used, specifically a Wilcoxon signed-ranks test. Results indicated a significant increase in content knowledge occurred over time between the pre- (Mdn=0.35) and post-testing time points (Mdn=0.80) z=-2.49, p<,05, r=-0.59 for the electronic theory portion of the curriculum. An equivalent control group was recruited from the remaining participant pool, allowing for comparison between groups. The program design, findings, and lessons learned will be reported in this paper. DA - 2014/// PY - 2014/// DO - 10.1117/12.2070742 VL - 9289 SP - SN - 1996-756X KW - photonics KW - fiber optics KW - electronic theory KW - high school ER - TY - JOUR TI - Postharvest performance of cut marigold, rose, and sunflower stems as influenced by homemade and commercial floral preservatives AU - Ahmad, Iftikhar AU - Dole, John Martin T2 - TURKISH JOURNAL OF AGRICULTURE AND FORESTRY AB - Effects of homemade or commercial floral preservatives, applied as 48-h grower treatments or continuous retailer/consumer applications, were studied on cut Double Eagle marigold, Red Bentley rose, and Sunbright sunflower. Cut stems of marigold placed in preservative solutions, irrespective of the duration, had a longer vase life than stems in tap water. Continuous use of soda (7 Up) or citric-Kathon and short-term use of citric-Al resulted in the longest extension of vase life. Cut stems of rose had the longest vase life when pulsed with citric-Kathon for 48 h or continuously placed in citric-Al until termination. For sunflower, use of citric-Kathon or citric-Greenshield both as a pulse and as a vase solution extended the vase life similar to commercial preservatives such as Floralife or Chrysal; it was 1.8 days longer than the vase life of stems in tap water. Continuous use of lemon juice plus sugar or citric acid plus sugar reduced the vase life of rose and sunflower stems. The pH of tap water solutions became more acidic when used after 48 h of pulsing with preservative solutions, while greater changes in electrical conductivity were recorded when the preservative solutions containing soda, lemon juice plus sugar, or citric-Al were used until termination. Stems of all species tested kept continuously in soda had the highest dry weight, while citric-Kathon had higher fresh weight at termination, compared to initial fresh weight at harvest, and higher solution uptake. In summary, continuous vase application of citric-Kathon, soda, or citric-Greenshield resulted in the best postharvest performance of marigold and sunflower, and continuous treatment with citric-Al or pulsing with citric-Kathon resulted in the best postharvest performance of cut roses; all of the aforementioned treatments resulted in a vase life similar to those of commercial preservatives. However, mixtures containing lemon juice or citric acid plus sugar had detrimental effects and should not be used for longer periods to handle cut stems of rose or sunflower. DA - 2014/// PY - 2014/// DO - 10.3906/tar-1402-31 VL - 38 IS - 6 SP - 916-925 SN - 1303-6173 KW - Aluminum sulfate KW - citric acid KW - cut flowers KW - folk recipes KW - rose KW - vase life ER - TY - JOUR TI - Refining Postharvest Handling Procedures Increased Cut Rose Vase Life AU - Moody, Erin P. AU - Dole, John M. AU - Barnes, Jared T2 - HORTTECHNOLOGY AB - Various postharvest procedures were conducted on several rose ( Rosa hybrida ) cultivars to determine the effects on vase life, water uptake, change in fresh weight, stage of opening, and vase life termination criteria. Vase life was influenced by cultivar and vase solution. Commercial preservative solutions resulted in a longer vase life, smaller decrease in fresh weight than the controls, and smaller increase in water uptake. Vase life of nine cultivars in distilled water ranged from a low of 7.1 days for Queen 2000 to a high of 15.3 days for Forever Young. Flower termination criteria were also cultivar specific with Black Baccara, Classy, and Charlotte most prone to bent neck and blackening of petal tips. Exogenous ethylene at 0.4 or 4.0 μL·L −1 did not affect vase life but lowered water uptake. Application of the antiethylene agent silver thiosulfate (STS) at 0.2 m m concentration significantly improved vase life in five out of the nine cultivars (Anna, Charlotte, First Red, Freedom, and Konfetti) tested, but 1-methylcyclopropene (1-MCP) at 740 nL·L −1 did not improve vase life over the control. Both vase life and water uptake were reduced when more than one stem was placed in a vase; placing 10 stems in a vase shortened vase life by 1.4 days and impeded water uptake by up to 10.6 mL/stem per day. Increasing the amount of time stems remained dry before placing in a vase reduced vase life, but recutting immediately before placing in a vase minimized the decline. Increasing the amount of stem cut off the base up to 10 cm increased vase life. DA - 2014/12// PY - 2014/12// DO - 10.21273/horttech.24.6.676 VL - 24 IS - 6 SP - 676-685 SN - 1943-7714 KW - Rosa hybrida KW - 1-methylcyclopropene KW - ethylene KW - silver thiosulfate KW - senescence ER - TY - JOUR TI - Pulsing With Low Concentration Gibberellin Plus Benzyladenine or Commercial Floral Preservatives Affect Postharvest Longevity, Quality, and Leaf Chlorosis of Cut Lilies and Gladioli AU - Ahmad, Iftikhar AU - Dole, John M. AU - Favero, Bruno T. T2 - HORTTECHNOLOGY AB - Effects of pulsing with different concentrations of gibberellin plus benzyladenine (GA 4+7 + BA), a proprietary mixture of GA 4+7 plus BA in a commercial floral preservative (GA 4+7 + BA + preservative), or a propriety mixture of sugar plus acidifier developed for bulbous flowers (floral bulb preservative) were studied on postharvest performance and quality of cut lily ( Lilium hybrids) and gladiolus ( Gladiolus hybrids) flowers. Pulsing of cut stems of lily with GA 4+7 + BA at 5 or 2 mL·L −1 GA 4+7 + BA + preservative for 20 hours at 3 ± 1 °C extended the vase life and controlled leaf chlorosis of ‘Cobra’ oriental lily and ‘Cappuccino’ and ‘Dot Com’ asiatic lily. Cut ‘Orange Art’ asiatic lily performed best when pulsed with GA 4+7 + BA at 10 mg·L −1 . For cut gladiolus, pulsing with GA 4+7 + BA at 10 mg·L −1 extended the vase life of ‘Alice’, ‘Mammoth’, and ‘Passion’, while ‘Scarlet’ had the longest vase life when pulsed with 5 mg·L −1 GA 4+7 + BA. GA 4+7 + BA + preservative also extended the vase life and controlled leaf chlorosis, but the floral bulb preservative had no effect on vase life extension or preventing leaf chlorosis of lilies. Gladiolus cultivars had no or minor leaf chlorosis during vase period. Overall, overnight pulsing with GA 4+7 + BA or GA 4+7 + BA + preservative extended the vase life and prevented leaf chlorosis and can be used by growers and wholesalers for maintaining quality of cut stems. DA - 2014/10// PY - 2014/10// DO - 10.21273/horttech.24.5.560 VL - 24 IS - 5 SP - 560-564 SN - 1943-7714 KW - plant growth regulators KW - senescence KW - vase life ER - TY - JOUR TI - Postharvest Handling Recommendations for Cut Pineapple Lily AU - Carlson, Alicain S. AU - Dole, John M. T2 - HORTTECHNOLOGY AB - The effects of various postharvest treatments on cut stems of ‘Coral’ and ‘Sparkling Burgundy’ pineapple lily ( Eucomis sp.) were evaluated to determine best postharvest handling practices. The use of a commercial hydrator, holding solution, or both significantly reduced vase life for ‘Coral’; the deionized (DI) water control had the longest vase life. ‘Sparkling Burgundy’ vase life was significantly reduced to 29.9 days when both a commercial hydrator and holding solution were used as compared with 50.3 days when DI water was the hydrator used with the commercial holding solution. The use of a bulb-specific preservative reduced vase life of ‘Coral’ to 43.8 days, while the DI water control had a vase life of 66.4 days, and commercial holding solution was intermediate at 56.8 days. A 10% sucrose pulse reduced vase life to 46.9 days compared with the 0% sucrose control (58.9 days) and the 20% sucrose concentration (62.5 days), which were not significantly different. The use of floral foam and/or 2% or 4% sucrose concentrations plus isothiazolinone reduced vase life significantly to an average of 11.1 days. The vase life of stems cold stored at 2 °C for 1 week (37.7 days) was not significantly different from the unstored stems (43.0 days), while longer storage times up to 3 weeks significantly reduced vase life. The use of hydrating solution pretreatments before and holding solution treatments during 4 days of cold storage had no significant effect on vase life. ‘Sparkling Burgundy’ stems harvested with 100% of the florets open had the longest vase life of 51.2 days compared with 38.4 days when 1% of the florets were open. Vase life was unaffected by exogenous ethylene exposure up to 1 ppm for 16 hours. For best postharvest quality, ‘Coral’ and ‘Sparkling Burgundy’ pineapple lily should be harvested when at least 50% of the florets are open, held in plain water without preservatives, and stored for no more than 1 week (wet or dry) at 2 °C. DA - 2014/12// PY - 2014/12// DO - 10.21273/horttech.24.6.731 VL - 24 IS - 6 SP - 731-735 SN - 1943-7714 KW - Eucomis KW - sucrose pulses KW - preservatives KW - hydrator KW - holding solution ER - TY - JOUR TI - Paclobutrazol and ancymidol lower water use of potted ornamental plants and plugs AU - Ahmad, I. AU - Whipker, B. E. AU - Dole, J. M. AU - McCall, I. T2 - European Journal of Horticultural Science DA - 2014/// PY - 2014/// VL - 79 IS - 6 SP - 318-326 ER - TY - JOUR TI - Optimal postharvest handling protocols for cut 'Line Dance' and 'Tap Dance' Eremurus inflorescences AU - Ahmad, Iftikhar AU - Dole, John M. AU - Schiappacasse, Flavia AU - Saleem, Muhammad AU - Manzano, Elizabeth T2 - SCIENTIA HORTICULTURAE AB - Eremurus, commonly known as Foxtail lily, is a novel, commercially important specialty cut flower, but postharvest handling procedures need to be optimized for longest vase life. Cut inflorescences of ‘Line Dance’ and ‘Tap Dance’ eremurus were evaluated for optimal harvest stage, harvest procedures, effects of anti-ethylene agents, and storage methods and duration. Also, the effects of commercial hydrators, hydrators along with holding preservatives, or continuous use of floral foam saturated with or without commercial preservatives were investigated. Inflorescences of both cultivars harvested with 0 florets open had longer vase life than stems harvested with 3–5 rows of florets opened. Handling of ‘Line Dance’ stems in water after harvest extended the vase life, but reduced the vase life of ‘Tap Dance’ compared to inflorescences handled dry. Application of anti-ethylene agents had no significant effect on eremurus longevity. Inflorescences of both cultivars stored for 1 week had similar vase life as of unstored stems irrespective of dry or wet storage. Storage longer than 1 week greatly reduced the vase life of both cultivars. Use of either or both hydrator and holding preservatives did not result in significant differences in vase life for both cultivars, while pulsing with 10% sucrose supplemented with an antimicrobial agent, isothiazolinone at 0.007 mL L−1, for 24 h extended vase life by 2.2 or 1.9 d for ‘Line Dance’ and ‘Tap Dance’ inflorescences, respectively, compared with tap water. Inflorescences of ‘Line Dance’ kept continuously in commercial preservatives had longest vase life compared with tap water and use of floral foam reduced vase life. However, inflorescences of ‘Tap Dance’ kept continuously in floral foam saturated with tap water, or just Floralife Clear Professional Flower food had longest vase life. DA - 2014/11/24/ PY - 2014/11/24/ DO - 10.1016/j.scienta.2014.09.031 VL - 179 SP - 212-220 SN - 1879-1018 KW - Dry storage KW - Fox-tail lily KW - Harvest stage KW - Hydrators KW - Pulsing KW - Vase life ER - TY - JOUR TI - Frank A. Blazich Death AU - Blazich, Frank, Jr. AU - Dole, John M. T2 - HORTSCIENCE DA - 2014/8// PY - 2014/8// DO - 10.21273/hortsci.49.8.1122 VL - 49 IS - 8 SP - 1122-1122 SN - 2327-9834 ER - TY - JOUR TI - Family Coaching: An Emerging Family Science Field AU - Allen, Kimberly AU - Huff, Nichole L. T2 - FAMILY RELATIONS AB - Although there is a rich history of collaboration and distinction among family practitioners, to remain progressive, the domains of family practice must continue to evolve based on the current practices of family professionals. Recently, family coaching (FC) has captured the professional attention of practitioners as another collaborative yet distinct field in family science. FC seeks to foster the achievement of family-identified goals through a process-driven relationship between a family and professional coach. In this article, the authors introduce FC and explore it as an extension to the domains of family practice model. In addition, the authors offer results from a nationwide sample of family practitioners (N = 180) regarding their experiences and opinions of FC to further substantiate the field's progression. DA - 2014/12// PY - 2014/12// DO - 10.1111/fare.12087 VL - 63 IS - 5 SP - 569-582 SN - 1741-3729 KW - coaching psychology KW - domains of family practice KW - family case management KW - family coaching KW - family life education KW - family therapy ER - TY - JOUR TI - Postharvest performance of cut carnation, chrysanthemum and rose as influenced by conventional and organic floral preservatives AU - Ahmad, Iftikhar AU - Dole, John M. AU - Viloria, Zenaida AU - Blazich, Frank A. T2 - BIOLOGICAL AGRICULTURE & HORTICULTURE AB - AbstractSelected commercial preservatives were tested to determine the optimum conventional and organic hydrator and holding solutions for vase life extension and suppression of microbial populations in vase solutions of cut carnation (Dianthus caryophyllus L.) Select Red, chrysanthemum [Dendranthemum grandiflora (Ramat.) Kitam.] Anastasia, and rose (Rosa × hybrida L.) Freedom. Hydrators extended vase life of carnation but had no effect on chrysanthemum or rose. Chrysal Professional 2 (conventional holding solution), after hydration with deionized (DI) water, extended vase life of cut carnation to 36.0 days compared with DI water or Vita One Step (organic preservative solution), resulting in vase lives of 21.0 or 20.9 days, respectively. For chrysanthemum, all preservative solutions had statistically similar vase life. Holding solutions increased vase life of cut roses and carnation, but were ineffective for chrysanthemum. The greatest vase life extension occurred with Floralife Premium Rose Food (conventional holding solution), 7.9 and 7.3 days longer, than with DI water in cut Freedom roses after treatment with Floralife Hydraflor 100 (conventional hydrator solution) and DI water, respectively. However, Vita One Step (organic hydrator and holding solution) reduced vase life by 2.4 days and had higher bent neck incidence (93%) than DI water. Floralife Premium Rose Food and Chrysal Rose Vase (conventional holding solution) effectively controlled bent neck. DI water with organic Vita products had higher bacterial populations than conventional products for all species tested. Among the preservatives investigated, conventional products increased vase life more than organic products, indicating the need for organic preservatives with effective antimicrobial activity.Keywords:: cut flowersDendranthemum grandifloraDianthus caryophyllusholding solutionshydratorRosa × hybridavase life AcknowledgementsThe authors are grateful to Sunburst Flower Farms, Colombia, South America for stems of carnation and chrysanthemum and Dole Fresh Flowers, Miami, FL, USA, for providing stems of roses and Erin M.R. Clark for technical support. Critical reviews of this manuscript by Julia L. Kornegay, John D. Williamson, and Bryon R. Sosinski are gratefully acknowledged.Additional informationFundingFundingThe authors are grateful to the Endowment Fund Secretariat, University of Agriculture, Faisalabad, Pakistan for the financial support of the senior author and North Carolina Agricultural Research Service (NCARS), Raleigh, NC 27695-7643, USA, for partial funding of this study. Use of trade names in this publication does not imply endorsement by the NCARS of products named nor criticism of similar ones not mentioned. DA - 2014/4/3/ PY - 2014/4/3/ DO - 10.1080/01448765.2013.878880 VL - 30 IS - 2 SP - 109-118 SN - 2165-0616 KW - holding solutions KW - Dendranthemum grandiflora KW - cut flowers KW - Dianthus caryophyllus KW - vase life KW - hydrator KW - Rosaxhybrida ER - TY - JOUR TI - Optimal postharvest handling protocols for Celosia argentea var. cristata L. 'Fire Chief' and Antirrhinum majus L. 'Chantilly Yellow' AU - Ahmad, Iftikhar AU - Dole, John M. T2 - SCIENTIA HORTICULTURAE AB - Celosia (Celosia argentea var. cristata L.) and snapdragon (Antirrhinum majus L.) are commercially important specialty cut flowers, but postharvest handling protocols for extending vase life need to be optimized. Stems of ‘Fire Chief’ celosia harvested when the flower heads were <2 cm in diameter had 14.0 days longer vase life than stems harvested with flower heads >5 cm at harvest, while ‘Chantilly Yellow’ snapdragon stems harvested when the lowermost florets started expanding had 3.4 days more vase life than stems harvested with three to five florets opened at harvest. However, visual quality of later-harvested stems of both species was higher than early harvested stems due to showier, larger flower celosia heads and a greater number of total florets of snapdragon spikes opened during the vase period. Harvest procedures, exogenous ethylene, anti-ethylene agents, and commercial hydrators had no effect on longevity of both species except silver thiosulfate, an anti-ethylene agent, increased vase life of snapdragon 3.2 or 3.7 days more than deionized (DI) water or 1-methylcyclopropene, respectively. Stems of celosia did not tolerate storage at 3 ± 1 °C, irrespective of the storage method, and if necessary, should only be stored for ≤1 week in water. On the other hand, snapdragon stems could be dry-stored for 2 weeks with no decrease in vase life and had a longer vase life than stems stored in water. Pulsing with 5 or 10% sucrose supplemented with the antimicrobial agent, isothiazolinone at 0.007 mL L−1, for 24 h, and use of hydrator for 4 hours and/or holding preservatives for 44 h reduced vase life of celosia stems compared to DI water. Whereas, use of both hydrator for 4 h and holding preservatives for 44 h did not result in significant differences in vase life, but pulsing with 5 or 10% sucrose supplemented with the antimicrobial agent, isothiazolinone at 0.007 mL L−1, for 24 h doubled vase life of snapdragon stems and increased flower bud opening and fresh weight of stems during the vase period. Celosia stems kept continuously in Floralife Clear Professional Flower Food with or without floral foam had longer vase life compared with Chrysal Clear Universal Flower Food or foam saturated with DI water, while snapdragon stems kept continuously in commercial preservatives had 2-fold longer vase life compared with DI water. Floral foam reduced vase life of snapdragon when saturated with preservatives, or had no effect when saturated with DI water. Vase life and quality of both ‘Fire Chief’ celosia and ‘Chantilly Yellow’ snapdragon stems can be extended by following appropriate postharvest handling procedures. DA - 2014/6/9/ PY - 2014/6/9/ DO - 10.1016/j.scienta.2014.04.026 VL - 172 SP - 308-316 SN - 1879-1018 KW - Anti-ethylene agents KW - Celosia KW - Dry storage KW - Floral foam KW - Harvest stage KW - Holding solutions KW - Hydrators KW - Pulsing KW - Snapdragon KW - Vase life ER - TY - JOUR TI - Determining Optimal Production Temperature, Transplant Stage, and Postharvest Protocols for Cut 'Esprit' Penstemon AU - Carlson, Alicain S. AU - Dole, John M. T2 - HORTTECHNOLOGY AB - The effects of production temperature and transplant stage on stem length and caliper of cut stems and postharvest treatments on vase life of ‘Esprit’ penstemon ( Penstemon grandiflorus ) were examined. Plugs transplanted with eight to nine sets of true leaves had a longer stem length (64.3 cm) at harvest than those transplanted with two to three sets (57.7 cm) or five to six sets (60.8 cm). Time to flowering from transplant shortened as production temperature increased and when transplants had a greater number of true leaves. The addition of 2% or 4% sucrose with 7 ppm isothiazolinone as a vase solution resulted in the longest vase life (9.4 days) of all treatments compared with the control (4.5 days). A holding solution increased vase life to 7.0 days for Floralife holding solution and 5.9 days for Chrysal holding solution from the 4.3 days control, although hydrating solutions and preservative brand had no effect. The use of floral foam or antiethylene agents, ethylene exposure, or sucrose pulses also had no effect on vase life. Extended cold storage lengths either wet or dry for 2 or 3 weeks caused vase life to decrease to 2.0 days when compared with 5.6 days for the unstored control and 7.6 days for 1 week storage. ‘Esprit’ penstemon may be suitable for greenhouse production and has acceptable potential as a locally grown specialty cut flower. DA - 2014/2// PY - 2014/2// DO - 10.21273/horttech.24.1.71 VL - 24 IS - 1 SP - 71-75 SN - 1943-7714 KW - beardtongue KW - cold storage KW - ethylene KW - Penstemon grandiflorus KW - preservative ER - TY - JOUR TI - Effects of Daily Harvest Time on Postharvest Longevity, Water Relations, and Carbohydrate Status of Selected Specialty Cut Flowers AU - Ahmad, Iftikhar AU - Dole, John M. AU - Blazich, Frank A. T2 - HORTSCIENCE AB - Effects of harvest time (morning, noon, or afternoon) on water uptake, fresh weight changes, termination symptoms, leaf relative water content (LRWC), carbohydrate status, and vase life of cut ‘ABC Purple’ lisianthus ( Eustoma grandiflorum Salisb.), ‘Double Eagle’ African Gold Coin Series marigold ( Tagetes erecta L.), and ‘Deep Red’ Benary’s Giant Series zinnia ( Zinnia elegans Jacq.) were studied. For stems of lisianthus harvested and then stored in the dark with the basal ends in water for 2 weeks at 3 ± 1 °C, those harvested at noon (1200 hr to 1300 hr ) or in the afternoon (1700 hr to 1800 hr ) had longer vase life compared with stems harvested in the morning (0700 hr to 0800 hr ). However, stems of lisianthus evaluated without storage had no differences in vase life. Stems of marigold harvested in the afternoon had longer vase life than morning- or noon-harvested stems. Time of harvest had no effect on cut flower longevity of zinnia. However, vase life was considerably shorter for stems of all species when tested after 2 weeks storage compared with freshly harvested stems. Stems of zinnia harvested at noon had lower LRWC than morning- or afternoon-harvested stems. Marigold stems harvested in the afternoon and evaluated without storage had lowest LRWC on Day 7 of vase life. Harvest time or storage did not influence LRWC of lisianthus. Stems of marigold and lisianthus harvested at noon or in the afternoon had higher levels of carbohydrates compared with morning-harvested stems, whereas freshly harvested stems had higher concentrations of glucose and sucrose, which decreased during storage or the vase period. Sucrose concentrations varied more significantly among various tissues than other sugars presumably as a result of translocation during vase life. In summary, carbohydrate status of stems harvested at different times of the day varied greatly and affected postharvest longevity of cut marigold and lisianthus, but not zinnia. DA - 2014/3// PY - 2014/3// DO - 10.21273/hortsci.49.3.297 VL - 49 IS - 3 SP - 297-305 SN - 2327-9834 KW - cut flowers KW - Eustoma grandiflorum KW - fructose KW - glucose KW - sucrose KW - Tagetes erecta KW - Zinnia elegans ER - TY - JOUR TI - Compartment Proteomics Analysis of White Perch (Morone americana) Ovary Using Support Vector Machines AU - Schilling, Justin AU - Nepomuceno, Angelito AU - Schaff, Jennifer E. AU - Muddiman, David C. AU - Daniels, Harry V. AU - Reading, Benjamin J. T2 - JOURNAL OF PROTEOME RESEARCH AB - Compartment proteomics enable broad characterization of target tissues. We employed a simple fractionation method and filter-aided sample preparation (FASP) to characterize the cytosolic and membrane fractions of white perch ovary tissues by semiquantitative tandem mass spectrometry using label-free quantitation based on normalized spectral counts. FASP depletes both low-molecular-weight and high-molecular-weight substances that could interfere with protein digestion and subsequent peptide separation and detection. Membrane proteins are notoriously difficult to characterize due to their amphipathic nature and association with lipids. The simple fractionation we employed effectively revealed an abundance of proteins from mitochondria and other membrane-bounded organelles. We further demonstrate that support vector machines (SVMs) offer categorical classification of proteomics data superior to that of parametric statistical methods such as analysis of variance (ANOVA). Specifically, SVMs were able to perfectly (100% correct) classify samples as either membrane or cytosolic fraction during cross-validation based on the expression of 242 proteins with the highest ANOVA p-values (i.e., those that were not significant for enrichment in either fraction). The white perch ovary cytosolic and membrane proteomes and transcriptome presented in this study can support future investigations into oogenesis and early embryogenesis of white perch and other members of the genus Morone. DA - 2014/3// PY - 2014/3// DO - 10.1021/pr401067g VL - 13 IS - 3 SP - 1515-1526 SN - 1535-3907 KW - compartment proteomics KW - support vector machines KW - modulated modularity clustering KW - ovary KW - oocytes KW - vitellogenin KW - transcriptome KW - mitochondria KW - alternatively spliced variants ER - TY - JOUR TI - Homemade Floral Preservatives Affect Postharvest Performance of Selected Specialty Cut Flowers AU - Ahmad, Iftikhar AU - Dole, John M. T2 - HORTTECHNOLOGY AB - Effects of homemade or commercial floral preservatives, applied as 48-hour grower treatment or continuous retailer/consumer application, were studied on cut ‘ABC Blue’ lisianthus ( Eustoma grandiflorum ), ‘Maryland Plumblossom’ snapdragon ( Antirrhinum majus ), ‘Mid Cheerful Yellow’ stock ( Matthiola incana ), and ‘Deep Red’ Benary’s zinnia ( Zinnia violacea ). Cut stems were placed in solutions containing 500 mL·L −1 lemon/lime soda (soda); 6 mL·L −1 lemon juice plus 20 g·L −1 sugar (lemon juice); 100 mg·L −1 citric acid plus 20 g·L −1 sugar plus 200 mg·L −1 aluminum sulfate (C-AS); 400 mg·L −1 citric acid plus 20 g·L −1 sugar alone (citric acid), or combined with either 0.5 mL·L −1 quaternary ammonium chloride (C-QA), or 0.007 mL·L −1 isothiazolinone (C-IS); 10 mL·L −1 Floralife Clear Professional Flower Food (Floralife); or 10 mL·L −1 Chrysal Clear Professional 2 (Chrysal), dissolved in tap water, which was also used as control without any added compound. Cut stems of lisianthus and stock had longest vase lives (22.1 and 12.7 days, respectively) when placed in C-IS continuously, while snapdragon and zinnia stems had longest vase lives (22.3 and 16.3 days, respectively) when placed in C-QA solution continuously. Continuous use of soda extended vase life of cut lisianthus, snapdragon, and stock stems, but not zinnia, compared with tap water. Citric acid extended the vase life of lisianthus and stock when used continuously and of zinnia when used for 48 hours. Use of C-AS or lemon juice either had no effect or reduced vase life of the tested species, except lemon juice increased zinnia vase life when used as a 48-hour treatment. Stems of lisianthus, stock, and zinnia placed continuously in C-IS, C-QA, or citric acid had high solution uptake. No significant differences were observed for vase life of all tested species with short duration (48 hours) application of solutions, except 48-hour use of citric acid or lemon juice increased zinnia vase life compared with tap water. Overall, continuous vase application of the homemade preservatives resulted in longer vase life extension than 48-hour treatment. Among tested preservative recipes, C-IS, C-QA, soda, or citric acid demonstrated best postharvest performance of tested species. However, recipes containing C-AS or lemon juice had detrimental effects and should not be used for handling cut stems of tested species. DA - 2014/6// PY - 2014/6// DO - 10.21273/horttech.24.3.384 VL - 24 IS - 3 SP - 384-393 SN - 1943-7714 KW - aluminum sulfate KW - citric acid KW - folk recipes KW - lisianthus KW - snapdragon KW - stock KW - vase life KW - zinnia ER - TY - JOUR TI - Floral foam and/or conventional or organic preservatives affect the vase-life and quality of cut rose (Rosa X hybrida L.) stems AU - Ahmad, Iftikhar AU - Dole, John M. AU - Clark, Erin M. R. AU - Blazich, Frank A. T2 - JOURNAL OF HORTICULTURAL SCIENCE & BIOTECHNOLOGY AB - SummaryWe studied the effects of floral foam (Oasis®), with or without conventional or organic preservatives, to determine the optimum treatment to extend the vase-life of the cut rose (Rosa × hybrida L.) cultivars ‘Freedom’ and ‘Charlotte’. In general, floral foam resulted in similar or reduced vase-lives in cut ‘Freedom’ and ‘Charlotte’ rose, and had no influence on the symptoms of senescence in either cultivar. ‘Freedom’ showed more petal browning and rot, as well as reduced flower bud opening, compared to ‘Charlotte’. Vase solutions containing either of two conventional preservatives resulted in longer vase-lives in the stems of both cultivars than stems in deionised (DI) water. Floral foam saturated with DI water resulted in greater changes in the pH of the vase solution in both cultivars. Among the preservatives tested, conventional products such as Floralife Premium Rose Food or Chrysal Rose Vase (each at 10 ml l–1) extended the vase-life by 5.5 d or 3.9 d, respectively; whereas organic products such as Vita Flora or Vita One Step (each at 0.53 ml l–1) resulted in statistically similar vase-lives (9.3 d or 8.3 d, respectively) as stems in DI water (7.5 d), irrespective of the use of floral foam. These findings suggest that floral foam should not be used during the post-harvest handling of cut rose stems. Moreover, conventional preservatives were more effective than the organic products. DA - 2014/1// PY - 2014/1// DO - 10.1080/14620316.2014.11513046 VL - 89 IS - 1 SP - 41-46 SN - 1462-0316 ER -