ASTM_D_4136_-_82_2012.pdf

Designation:D413682(Reapproved 2012)Standard Practice forSampling Phytoplankton with Water-Sampling Bottles1This standard is issued under the fixed designation D4136;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope1.1 This practice covers the procedures for obtaining quan-titative samples of a phytoplankton community by use ofwater-sampling bottles.1.2 This standard does not purport to address all of thesafety problems,if any,associated with its use.It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2D4137 Practice for Preserving Phytoplankton Samples3.Summary of Practice3.1 A sampler is lowered to a specified depth and closed bya messenger.The sampler is retrieved and the sample isremoved.The phytoplankton are preserved as dictated by theobjectives of the study.4.Significance and Use4.1 The advantages of water-sampling bottles are as fol-lows:4.1.1 Samples of known volume can be obtained from aprecise depth.4.1.2 A quantitative sample is obtained.Nanno-and ultra-plankton are not lost from the sampling device.4.1.3 A sampler of almost any desired volume or construc-tion material can be obtained.4.1.4 The sampler is light-weight and can be used withoutauxiliary equipment.4.1.5 There is a free flow of water through the cylinder ofthe sampler when it is being lowered.4.1.6 Samplers can be arranged serially to facilitate sam-pling at several depths almost simultaneously.4.1.7 The sampler can be used in most depths of water.4.2 The disadvantages of water-sampling bottles are asfollows:4.2.1 Samples are obtained from only discrete depths;theycannot be obtained from horizontal or vertical strata of water.4.2.2 The samplers cannot be used satisfactorily in fast-flowing water.4.3 There are several special considerations that shall beobserved when using water-sampling bottles.They are asfollows:4.3.1 The samplers should be protected from damage,whichcommonly results in leakage.4.3.2 Following use,the samplers should be hung open in ahorizontal position to allow for thorough drying.4.3.3 The end stoppers should be inspected periodically forsigns of wear or deterioration and replaced as necessary(Fig.1a,b,c).5.Apparatus5.1 Most water-sampling bottles,(Fig.1a,b,c,d),consist ofa cylindrical tube with stoppers at each end and a closingdevice activated by a messenger.The most commonly usedsamplers that operate on this principle are the Kemmerer,VanDorn,Nansen,and Fjarlie bottles.The Kemmerer and VanDorn bottles are similar in design and differ only in the designof the closure mechanism.The Nansen bottle is a reversingbottle in that when it is tripped,valves at each end close and thebottle rotates 180.The rotation releases a second messengerthat trips another sampler at a lower depth and so on.TheFjarlie bottle,designed for sampling from great depths,is alsoa series-type sampler and contains an auxiliary assembly formounting reversing thermometers.Most water-samplingbottles are available in a variety of construction materials(forexample,brass,clear acrylic,and polyvinyl chloride).Theymay be TFE-fluorocarbon-lined.The volume of the samplersvaries from about 0.2 to over 30 L.1This practice is under the jurisdiction of ASTM Committee D19 on Water andis the direct responsibility of Subcommittee D19.24 on Water Microbiology.Current edition approved Sept.1,2012.Published November 2012.Originallyapproved in 1982.Last previous edition approved in 2004 as D4136 82(2004).DOI:10.1520/D4136-82R12.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 6.Procedure6.1 Lower the sampler in the open position to a desireddepth,trip,and retrieve.The enclosed volume of watercontains the trapped organisms.Preserve the plankton asdescribed in Practice D4137.ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard.Users of this standard are expressly advised that determination of the validity of any such patent rights,and the riskof infringement of such rights,are entirely their own responsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revised,either reapproved or withdrawn.Your comments are invited either for revision of this standard or for additional standardsand sh