4,809 research outputs found

    Impact of pig slurry amendments on phosphorus, suspended sediment and metal losses in laboratory runoff boxes under simulated rainfall

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    peer-reviewedLosses of phosphorus (P) when pig slurry applications to land are followed by a rainfall event or losses from soils with high P contents can contribute to eutrophication of receiving waters. The addition of amendments to pig slurry spread on high P Index soils may reduce P and suspended sediment (SS) losses. This hypothesis was tested at laboratory-scale using runoff boxes under simulated rainfall conditions. Intact grassed soil samples, 100 cm-long, 22.5 cm-wide and 5 cm-deep, were placed in runoff boxes and pig slurry or amended pig slurry was applied to the soil surface. The amendments examined were: (1) commercial grade liquid alum (8% Al2O3) applied at a rate of 0.88:1 [Al:total phosphorus (TP)] (2) commercial-grade liquid ferric chloride (38% FeCl3) applied at a rate of 0.89:1 [Fe:TP] and (3) commercial-grade liquid poly-aluminium chloride (PAC) (10% Al2O3) applied at a rate of 0.72:1 [Al:TP]. The grassed soil was then subjected to three rainfall events (10.3 ± 0.15 mm h−1) at time intervals of 48, 72, and 96 h following slurry application. Each sod received rainfall on 3 occasions. Results across three rainfall events showed that for the control treatment, the average flow weighted mean concentration (FWMC) of TP was 0.61 mg L−1, of which 31% was particulate phosphorus (PP), and the average FWMC of SS was 38.1 mg L−1. For the slurry treatment, there was an average FWMC of 2.2 mg TP L−1, 47% of which was PP, and the average FWMC of SS was 71.5 mg L−1. Ranked in order of effectiveness from best to worst, PAC reduced the average FWMC of TP to 0.64 mg L−1 (42% PP), FeCl3 reduced TP to 0.91 mg L−1 (52% PP) and alum reduced TP to 1.08 mg L−1 (56% PP). The amendments were in the same order when ranked for effectiveness at reducing SS: PAC (74%), FeCl3 (66%) and alum (39%). Total phosphorus levels in runoff plots receiving amended slurry remained above those from soil only, indicating that, although incidental losses could be mitigated by chemical amendment, chronic losses from the high P index soil in the current study could not be reduced.The first author gratefully acknowledges the award of the EMBARK scholarship from IRCSET to support this study

    The Institute of Archaeology & Siegfried H. Horn Museum Newsletter Volume 29.2

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    ASOR 2007, Paul J. Ray, Jr. Babylon, Owen Chesnut Jesus Tomb, Owen Chesnut Random Surveyhttps://digitalcommons.andrews.edu/iaham-news/1034/thumbnail.jp

    The Institute of Archaeology & Siegfried H. Horn Museum Newsletter Volume 30.1

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    LaBianca Lecture, Owen Chesnut LaBianca Elected to ASOR Post, Paul J. Ray, Jr. Younker Lecture, Owen Chesnut Al-Maktába: The Bookstore Random Surveyhttps://digitalcommons.andrews.edu/iaham-news/1037/thumbnail.jp

    The Institute of Archaeology & Siegfried H. Horn Museum Newsletter Volume 31.1

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    Museum Tablets On-line, Paul J. Ray, Jr. Hasel Lecture, Owen Chesnut Younker Lecture, Owen Chesnut Al-Maktába: The Bookstore Random Surveyhttps://digitalcommons.andrews.edu/iaham-news/1041/thumbnail.jp

    An Advanced, Three-Dimensional Plotting Library for Astronomy

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    We present a new, three-dimensional (3D) plotting library with advanced features, and support for standard and enhanced display devices. The library - S2PLOT - is written in C and can be used by C, C++ and FORTRAN programs on GNU/Linux and Apple/OSX systems. S2PLOT draws objects in a 3D (x,y,z) Cartesian space and the user interactively controls how this space is rendered at run time. With a PGPLOT inspired interface, S2PLOT provides astronomers with elegant techniques for displaying and exploring 3D data sets directly from their program code, and the potential to use stereoscopic and dome display devices. The S2PLOT architecture supports dynamic geometry and can be used to plot time-evolving data sets, such as might be produced by simulation codes. In this paper, we introduce S2PLOT to the astronomical community, describe its potential applications, and present some example uses of the library.Comment: 12 pages, 10 eps figures (higher resolution versions available from http://astronomy.swin.edu.au/s2plot/paperfigures). The S2PLOT library is available for download from http://astronomy.swin.edu.au/s2plo

    The Institute of Archaeology & Siegfried H. Horn Museum Newsletter Volume 28.4

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    Jordan Conference in Washington, Paul J. Ray, Jr. Wolff Lecture, Carrie Rhodes Barkay Lecture, Owen Chesnuthttps://digitalcommons.andrews.edu/iaham-news/1032/thumbnail.jp

    The Institute of Archaeology & Siegfried H. Horn Museum Newsletter Volume 30.2

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    2008 ASOR Annual Meeting, Paul J. Ray, Jr. Grunewald Lecture, Owen Chesnut Research Symposium, Antje Gallewski Random Surveyhttps://digitalcommons.andrews.edu/iaham-news/1038/thumbnail.jp

    Nutrient management planning on Irish dairy farms

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    End of Project ReportThe objective of the work undertaken was to investigate nutrient use on intensive dairy farms. A survey of 12 dairy farms was undertaken in 1997 to determine nutrient management practices. These were compared with current nutrient advice and recommended practices. Data recording was completed by the farmer and supplemented by regular farm visits to assist with and validate the process. The mean farm size was 64.8 ha with an average of 128 cows and an annual milk yield per cow of 5594 kg. The mean stocking rate was 2.58 Livestock Units/ha. Dairy cows accounted for highest proportion of the total livestock with most of the younger stock consisting of dairy replacements. Approximately 80% of soil P levels were greater than 6 mg/l while 67% of soils had soil K levels in excess of 100 mg/l. The mean soil P and K levels on the grazing and silage areas were 11 and 128 mg/l, 12 and 117 mg/l, respectively. The mean farm nutrient balance (inputs - outputs) established an annual surplus of N, P and K of 304, 18 and 53 kg/ha, respectively. The adoption of nutrient management plans instead of current practice would reduce N, P and K inputs on average by 44, 13 and 24 kg/ha, respectively. The use of the Teagasc revised P nutrient advice would further reduce the P input requirements by 2 kg/ha. On average the farms had 90% of the 16 week slurry storage capacity. Approximately 14, 42, 14 and 31% of the slurry was applied in spring, summer, autumn and winter, respectively. In all cases there was significant between farm variability. The soil P fertility on the survey farms is skewed towards index 3 and 4 when compared with the average for all samples received at Johnstown Castle. There is no agronomic advantage in terms of crop or animal production for soils to have P levels in excess 10 mg/l. This result indicates that P inputs to farms of this type can be reduced in many cases without prejudicing production potential. The nutrient balance conducted highlighted the extent of the nutrient surpluses and the between farm variability. The data suggest that there is not a serious nutrient surplus on the survey farms, which would require the use of additional off-farm land for slurry recycling, as obtains on pig and poultry farms. The study also indicates that although farm unit cost savings may be small in adopting nutrient management planning, overall farm savings may be significant. For example on the survey farms, savings of up to £2,000 can be achieved apart from the obvious positive environmental impact

    Increase in Pile Capacity with Time in Missouri River Alluvium

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    The data measured in this study suggest that the increase in compressive pile capacity for a 42-ft long, HP14x102 pile, in a predominantly fine-grained Missouri River alluvium soil profile, increases by about 16 percent from days seven to forty-four after driving. It appears evident that Davisson’s (1973) failure criteria seems to agree fairly well with the observed plunging failure of two compressive pile-load failure tests performed in Missouri River alluvium. By comparison of compressive proof and failure tests performed on day forty-four after driving, it appears that loading a pile to some degree prior to failure, and then reloading the pile, has almost no affect on the load-settlement relationship. Hence, proof loaded piles in Missouri River alluvium that pass should be allowed for use beneath the structure. Finally, comparisons of tension and compression pile load test data have lead to two possible conclusions. First, the estimation of tip load by tell-tale data may not be accurate, and may underestimate the amount of load actually transferred to the tip. And second, it seems viable that, at this site, the skin friction that can be counted on in design is perhaps 55 to 60 percent of that calculated for compression
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