SOILS-L: 199710XX

is the compilation of discussion during Oct 97

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Date: Wed, 01 Oct 1997 00:02:08 -0600 From: Automatic digest processor (LISTSERV@crcvms.unl.edu) Subject: SOILS-L Digest - 28 Sep 1997 to 30 Sep 1997 There are 2 messages totalling 32 lines in this issue. Topics of the day: 1. drop measurement (2) ----------------------------------------------------------------------
Date: Tue, 30 Sep 1997 09:01:18 +0100 From: Clara Marti (cmarti@POSTA.UNIZAR.ES) Subject: drop measurement Dear group, We are working on rain simulation, and we have a problem: How we can measure the drop diameter? I've read that is possible to use the splash on a paper and with a mathematical expression, transform the value as the real diameter. Has anyone more information about this method? Wich is the mathematical expression? Any information will be apreciated, Thank you in advance Clara ------------------------------
Date: Tue, 30 Sep 1997 14:14:51 -0400 From: PEATCONS@AOL.COM Subject: Re: drop measurement Why couldn't you weigh a number of drops and calculate the volume from the weight and the density of water, then divide by the number of drops to find the volume per drop and then calculate the diameter of the sphere giving rise to that volume? John Peterson, GTF labs ------------------------------ End of SOILS-L Digest - 28 Sep 1997 to 30 Sep 1997 **************************************************
Date: Thu, 02 Oct 1997 03:48:53 -0600 From: Automatic digest processor (LISTSERV@crcvms.unl.edu) Subject: SOILS-L Digest - 30 Sep 1997 to 1 Oct 1997 There are 2 messages totalling 105 lines in this issue. Topics of the day: 1. drop measurement (2) ----------------------------------------------------------------------
Date: Wed, 1 Oct 1997 16:47:48 +1000 From: Brendan Williams (b.williams@VCAH.UNIMELB.EDU.AU) Subject: Re: drop measurement There are many ways to measure droplet size. In-situ methods that use laser beams directed through the droplet cloud. These determine the droplet spectrum either directly by measuring the shadow effect of each individual drop or indirectly by measuring the refracted light from a droplet cloud. These are relatively expensive methods. The cheapest method is to do as you suggest, use water sensitive card to record the droplet size. This card is available from Spraying Systems. When a water drop hits the yellow card it changes color to blue. You can then measure the blue stain to dtermine the drop size. The relationship between stain size and drop size is specified by the manufacturer of the water sensitive paper. Good luck. in color. re are At 09:01 AM 30/09/97 +0100, you wrote: )Dear group, ) We are working on rain simulation, and we have a problem: )How we can measure the drop diameter? I've read that is possible to use the )splash on a paper and with a mathematical expression, transform the value )as the real diameter. )Has anyone more information about this method? Wich is the mathematical )expression? )Any information will be apreciated, )Thank you in advance )Clara ) ) ******************************************************************* Brendan Williams ph 0353 622239 Lecturer in Agricultural Engineering fx 0353 622213 Longerenong College, Email: b.williams@vcah.unimelb.edu.au The University of Melbourne, RMB 3000, HORSHAM, 3401,VICTORIA,AUSTRALIA ******************************************************************* ------------------------------
Date: Wed, 1 Oct 1997 09:29:05 +0100 From: Claudio MARCHISIO (claudio.marchisio@REGIONE.PIEMONTE.IT) Subject: Re: drop measurement Dear Clara, a few lines from Norman Hudson, "Soil Conservation" B.T. Batsford Limited (1971, 1981) pages 51-2. "The earliest recorded measurement of the size of raindrops were made by Lowe in 1892 who caught raindrops on flat sheets of slate which were ruled off into squares so that the size of splashes could be measured. This method of calculating the size of drop from the size of the splash which it makes on collecting device is one of the most popular methods. One technique is to take an adsorbent paper and lightly dust on to the surface a very finely powdered water-soluble dye. In the dry state the dye is invisible but on exposure to rain each raindrop makes a roughly circular stain which can be measured later. The drop size can be calculated from the formula D=aS^b, where D is the drop diameter, S is the stain diameter, an a and b ara constats establisched by laboratory calibration for the paper used. The method is reviewed by Hall (1970 - "Use of the Stain Method in Determining the Drop-Size Distribution of Coarse Liquid Spays", Transactios American Society of Agricultural Engineers, 13, 1, 33-37, 41) and is increasingly attractive because the previously tedious job of measuring and counting the drop stains can now be accomplished by the use of electronic scanners and inage analysers (Attle et al, 1980 - "Applications of Image Analysis", American Laboratory, April 1980). Another popular approach is the "Flour Pellet" method (Hudson, 1964 - "The Flour Pelle Method for Measuring the Size of Raindrops", Research Bulletin 4, Department of Conservation, alisbury, Zimbawe). A samle of rain is caught in a dish containing flour. Each raindrop forms a small glubule of wet flour and when dried in an aven these set into hard pellets which can be separated from the rest of the flour. A laboratory calibration has previously established the relationship between the size of a pellet and the size of a pellet and the size of the drop which formed it." Hadson cited also some pressure transducers used to measur rainfall imact and can also measure the size and size distribution of raindrops. RPC Morgan ("Soil erosion and conservation") cited some works on drop size distribution: - Law and Pearson, 1943 - "The relationship of raindrop size and intensity", Trans. Am. Geophys. Un. 24, 452-60; - Mason and Andrews, 1960 - "Drop size distribution from various types of rain", Quart. J. Roy. Met. Soc. 86, 346-53; - Carter et al, 1974 - Raindrop characteristics in the south central United States", Trans. Am. Soc. Agric. Engnrs. 17, 1033-7. I looked also into some WMO pubblications on meteorological instruments but I didn't find anything about raindrop measurement. Ciao. ------------------------------ End of SOILS-L Digest - 30 Sep 1997 to 1 Oct 1997 *************************************************
Date: Thu, 09 Oct 1997 03:48:42 -0600 From: Automatic digest processor (LISTSERV@crcvms.unl.edu) Subject: SOILS-L Digest - 1 Oct 1997 to 8 Oct 1997 There are 2 messages totalling 42 lines in this issue. Topics of the day: 1. Microbe population measurement 2. unsubscribe ----------------------------------------------------------------------
Date: Wed, 8 Oct 1997 09:36:14 +0000 From: Cullan Riley (cullan.riley@LUTON.AC.UK) Subject: Re: Microbe population measurement Sorry for the time delay in replying to your posted message. I read the message and then placed it in my to reply folder in my e-mail and its taken me this long to get round to answering you...... I'm also a graduate student, my research centers around indentifying the level of soil microbial diversity in different agricultural ecosystems. I was intrigued to see you are using fumigation-incubation. Have you considered fumigation-extraction, a similar but more effective technique for soil microbial biomass. Similarly microbial phospholipid phosphate is a good method for linking metabolic activity and microbial biomass. One off-shoot of phospholipid analysis is that it can also be sued to determine fatty acid methyl ester profiles that can be used as an index of microbial diversity. I have references on all of these, or if you want to continue the discussion further please don't hesitate to e-mail me. Your Cullan Cullan Riley Graduate School Faculty of Science and Technology University of Luton ------------------------------
Date: Wed, 8 Oct 1997 17:52:24 -0500 From: THOMAS@DEM.EHNR.STATE.NC.US Subject: unsubscribe please take me off of this list. if anyone can tell me how to unsubscribe, it would help tremendously. Sorry to bother you all about this... Thanks. ------------------------------ End of SOILS-L Digest - 1 Oct 1997 to 8 Oct 1997 ************************************************
Date: Sun, 12 Oct 1997 00:01:53 -0600 From: Automatic digest processor (LISTSERV@crcvms.unl.edu) Subject: SOILS-L Digest - 8 Oct 1997 to 11 Oct 1997 There is one message totalling 44 lines in this issue. Topics of the day: 1. Microwave owen for soil moisture determination ----------------------------------------------------------------------
Date: Sat, 11 Oct 1997 19:21:20 +0100 From: Luca Bechini (bechini@IMIUCCA.CSI.UNIMI.IT) Subject: Microwave owen for soil moisture determination Dear listmembers, maybe it's a FAQ: I wish to know whether soil moisture determination with a microwave owen gives reliable results or not. If the method is reliable, where can I find detailed information? Thank you very much for your attention, Luca Bechini =========================================================== Luca Bechini, PhD student, University of Milano Institute of Agronomy tel +39-2-70.600.164 Faculty of Agriculture fax +39-2-70.633.243 Via Celoria, 2 e-mail: luca.bechini@unimi.it I-20133 Milano - Italy http://imiucca.csi.unimi.it/~agra/iami/iami0.html Italian Ph.D. Association: http://distart.ing.unibo.it/dott =========================================================== ------------------------------ End of SOILS-L Digest - 8 Oct 1997 to 11 Oct 1997 *************************************************
Date: Tue, 14 Oct 1997 00:02:05 -0600 From: Automatic digest processor (LISTSERV@crcvms.unl.edu) Subject: SOILS-L Digest - 11 Oct 1997 to 13 Oct 1997 There are 2 messages totalling 134 lines in this issue. Topics of the day: 1. Microwave owen for soil moisture determination (2) ----------------------------------------------------------------------
Date: Mon, 13 Oct 1997 09:07:04 +0000 From: Heinrich Hiemesch (IGEWA_GmbH@T-ONLINE.DE) Subject: Re: Microwave owen for soil moisture determination On Sat, 11 Oct 1997 19:21:20 +0100, you wrote: ) Dear listmembers, ) )maybe it's a FAQ: I wish to know whether soil moisture determination )with a microwave owen gives reliable results or not. )If the method is reliable, where can I find detailed information? )Thank you very much for your attention, )Luca Bechini It's possible to have reasonable results about soil moisture with a microwave oven after a drying time of about 10 minutes or more (power switch of the oven at max. position). I assume that the duration of the process is the information you are interested in mainly...=20 There is a DIN-paper (German standards) describing the methods for determing soil moisture. Since 1989 it includes a "part 2" concerning fast methods. If you are interested i'll send you a hardcopy - however it's written in German. Our own experiences are that if you are working on clay - e.g. for sealing purposes of landfills - you need to check the results of the microwave oven procedure against "normal" heating conditions (as it is stated out in the DIN). Dewatering of clay minerals may cause irritating effects (max 0.5%). In this case you'll have to reduce the power and increase the heating time until the results of both processes are equal. If you are working on sands or gravels instead, dewatering of minerals will have an neglective effect. Hope this helps, Heinrich Heinrich Hiemesch snail: IGEWA (R) GmbH mailto: IGEWA_GmbH@t-online.de Ingenieurbuero fuer Geotechnik und Wasser PF 1444 D-84667 Waldkraiburg ------------------------------
Date: Tue, 14 Oct 1997 14:56:34 +1000 From: Gareth Swarbrick (G.Swarbrick@UNSW.EDU.AU) Subject: Re: Microwave owen for soil moisture determination I agree that micowaving has been used for sucessfull soil moisture determination. In Australia there is a standard procedure for using microwaves for this purpose - AS1289.2.1.4. See: http://www.standards.com.au/ and http://www.standards.com.au/catalogue/script/Details.asp?SearchID=3D30806.0.= 352101 071134304&RN=3D18 The main concerns are that microwaves tend to drive more water from within clay soils due to the particle-water molecule bonding. This why Australia uses 105=B0 C for conventional drying rather than the British 50=B0 C - different drying temperatures have different efficiencies at removing interstitial moisture. Microwaves are very effective at this. Another concern, but not as common, is the risk of the soil igniting. This can occur when the soil contains a significant organic fraction. Gareth. ----- )On Sat, 11 Oct 1997 19:21:20 +0100, you wrote: ) )) Dear listmembers, )) ))maybe it's a FAQ: I wish to know whether soil moisture determination ))with a microwave owen gives reliable results or not. ))If the method is reliable, where can I find detailed information? ))Thank you very much for your attention, ))Luca Bechini ) )It's possible to have reasonable results about soil moisture with a )microwave oven after a drying time of about 10 minutes or more (power )switch of the oven at max. position). )I assume that the duration of the process is the information you are )interested in mainly... ) )There is a DIN-paper (German standards) describing the methods for )determing soil moisture. Since 1989 it includes a "part 2" concerning )fast methods. If you are interested i'll send you a hardcopy - however )it's written in German. ) )Our own experiences are that if you are working on clay - e.g. for )sealing purposes of landfills - you need to check the results of the )microwave oven procedure against "normal" heating conditions (as it is )stated out in the DIN). Dewatering of clay minerals may cause )irritating effects (max 0.5%). In this case you'll have to reduce the )power and increase the heating time until the results of both )processes are equal. ) )If you are working on sands or gravels instead, dewatering of minerals )will have an neglective effect. ) )Hope this helps, )Heinrich ) )Heinrich Hiemesch snail: IGEWA (R) GmbH )mailto: IGEWA_GmbH@t-online.de Ingenieurbuero fuer ) Geotechnik und Wasser ) PF 1444 ) D-84667 Waldkraiburg --------------------------------------------------------------------------- Gareth Swarbrick __ ^ Interests: School of Civil Engineering _/ \__/ \ Municipal Waste, University of New South Wales / \ Mud & Sydney, Australia 2052 / \ Macs Internet: \ ____ */ mailto:G.Swarbrick@unsw.edu.au \_/ \___/ mailto:gareth@civeng.unsw.edu.au __o __ Phone: +61-2-9385-5016 --- +-\(: --- \/ "In vino e veritas" =46ax: +61-2-9385-6139 ---..(O)/(O)..--- http://www.civeng.unsw.edu.au/staff/geotech/swarbrick.htm --------------------------------------------------------------------------- ------------------------------ End of SOILS-L Digest - 11 Oct 1997 to 13 Oct 1997 **************************************************
Date: Wed, 15 Oct 1997 00:02:31 -0600 From: Automatic digest processor (LISTSERV@crcvms.unl.edu) Subject: SOILS-L Digest - 13 Oct 1997 to 14 Oct 1997 There is one message totalling 23 lines in this issue. Topics of the day: 1. Soil Test with a microwave ----------------------------------------------------------------------
Date: Tue, 14 Oct 1997 09:37:05 -0500 From: Ralph Anderson (cnty4093@UNLVM.UNL.EDU) Subject: Soil Test with a microwave There has been limited discussion of doing soil moisture tests with microwaves. The Aussie's offer a set of stanards for $9.50 plus but since I'm such a cheap skate, I'm looking for free advise. My interest would be to use the test as a teaching tool to teach soil moisture determination by sight and feel, such as go out to a field and collect several samples of soil of different texture and moiture level and then confirm our estimates in a microwave, if we could get the test results quickly. How long would we have to heat the soil to get an approximate reading(+/- 5%)? Could we put several samples in at one time?? Thanks! Ralph Anderson Extension Educator Ph (308) 236-1235 Fax (308) 234 6319 1400 E 34 E-Mail cnty4093@unlvm.unl.edu Kearney NE 68847 Home Page http://ianrwww.unl.edu/ianr/screc/fortepu/Buffalo/Buffalo.htm ------------------------------ End of SOILS-L Digest - 13 Oct 1997 to 14 Oct 1997 **************************************************
Date: Thu, 16 Oct 1997 00:01:12 -0600 From: Automatic digest processor (LISTSERV@crcvms.unl.edu) Subject: SOILS-L Digest - 14 Oct 1997 to 15 Oct 1997 There is one message totalling 54 lines in this issue. Topics of the day: 1. Soil Test with a microwave ----------------------------------------------------------------------
Date: Wed, 15 Oct 1997 08:27:34 +0000 From: Heinrich Hiemesch (IGEWA_GmbH@T-ONLINE.DE) Subject: Re: Soil Test with a microwave On Tue, 14 Oct 1997 09:37:05 -0500, you wrote: )There has been limited discussion of doing soil moisture tests with )microwaves. The Aussie's offer a set of stanards for $9.50 plus but = since )I'm such a cheap skate, I'm looking for free advise. My interest would = be )to use the test as a teaching tool to teach soil moisture determination = by )sight and feel, such as go out to a field and collect several samples of )soil of different texture and moiture level and then confirm our = estimates )in a microwave, if we could get the test results quickly. How long = would we )have to heat the soil to get an approximate reading(+/- 5%)? Could we = put )several samples in at one time?? Thanks! )Ralph Anderson )Extension Educator Ph (308) 236-1235 Fax (308) 234 6319 )1400 E 34 E-Mail cnty4093@unlvm.unl.edu )Kearney NE 68847 )Home Page http://ianrwww.unl.edu/ianr/screc/fortepu/Buffalo/Buffalo.htm You should calculate about 10 to 15 minutes for heating out your probes in the microwave (power switch at maximum position). Please mention, that you can do tests at your on: heat the probes you want to test minute-wise until the weight of the probe remains constant. You can heat several samples at the same time without problems. The micowave oven should have a good ventilation though. Best is to have the probes in glass bowls and to fill them in not very dense (sorry for poor my english - hope you understand what I mean). Heinrich Heinrich Hiemesch snail: IGEWA (R) GmbH mailto: IGEWA_GmbH@t-online.de Ingenieurbuero fuer Geotechnik und Wasser PF 1444 D-84667 Waldkraiburg ------------------------------ End of SOILS-L Digest - 14 Oct 1997 to 15 Oct 1997 **************************************************
Date: Fri, 17 Oct 1997 00:02:16 -0600 From: Automatic digest processor (LISTSERV@crcvms.unl.edu) Subject: SOILS-L Digest - 15 Oct 1997 to 16 Oct 1997 There is one message totalling 84 lines in this issue. Topics of the day: 1. Post-doc Position in Soil-water and Plant Relationship Available Now! ----------------------------------------------------------------------
Date: Thu, 16 Oct 1997 07:42:05 -0400 From: "Ali Fares, Ph.D." (af@GNV.IFAS.UFL.EDU) Subject: Post-doc Position in Soil-water and Plant Relationship Available Now! This is a multi-part message in MIME format. --------------C55ED7BCABEBD49C188793CE POSTDOC ASSOCIATE - NITROGEN CHEMISTRY AND USE EFFICIENCY: To conduct cooperative research to develop best management practice for nitrogen fertilization of citrus in deep sandy soils under heavy rainfall and micro-irrigation conditions. The study will focus to increase N use efficiency by citrus trees with an improved understanding on the nitrogen metabolism within the tree, while minimizing losses including volatilization and leaching. Basic investigations on N transformation, mineralization, N uptake and partioning within the tree, volatilization, denitrification, and leaching losses are required. The candidate must have good background in soil chemistry, soil physics, plant physiology, environmental chemistry, solute transport, dynamics of N in soils and within the tree including 15 N studies, and application of computer models to study leaching losses. Some knowledge of irrigation scheduling, fertigation, techniques for measuring soil moisture in field condition, and crop water requirement is desirable. The candidate must have experience and interest to conduct field experiments along with controlled basic investigations. Experience in tree crop nutrition and N budgeting for tree crop is preferred. The position is available immediately for a years appointment likely to be renewed subject to availability of funding. Please send your resume, list of publications and names of three references to: A. K. Alva, Citrus Research and Education Center, Lake Alfred, FL 33850. Phone no. 941-956-1151, Fax No. 941-956-4631, E-Mail: AKA@GNV.IFAS.UFL.EDU. --------------C55ED7BCABEBD49C188793CE Content-Description: Card for Ali Fares Content-Disposition: attachment; filename="vcard.vcf" begin: vcard fn: Ali Fares n: Fares;Ali org: University of Florida adr: CREC, University of Florida;;;Lake Alfred;FLorida;33880;USA email;internet: af@gnv.ifas.ufl.edu title: Research Associate tel;work: 941-956-1151 Ext 308 tel;fax: (941)-956-4631 x-mozilla-cpt: ;0 x-mozilla-html: FALSE end: vcard --------------C55ED7BCABEBD49C188793CE-- ------------------------------ End of SOILS-L Digest - 15 Oct 1997 to 16 Oct 1997 **************************************************

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