1、Designation:D413482(Reapproved 2012)Standard Practice forSampling Phytoplankton with a Clarke-Bumpus PlanktonSampler1This standard is issued under the fixed designation D4134;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year o
2、f 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 semi-quantitative samples of a phytoplankton community by use ofa Clark
3、e-Bumpus plankton sampler.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
4、 to use.2.Referenced Document2.1 ASTM Standards:2D4137 Practice for Preserving Phytoplankton Samples3.Summary of Practice3.1 The sampler is towed from a moving boat at a specifieddepth.The sampler uses a net for the concentration oforganisms and,as such,may be considered to be a semiquan-titative sa
5、mpler.It is quantitative in that the actual volume ofwater entering the sampler is measured by a calibrated flowmeter.The phytoplankton are preserved as dictated by theobjectives of the study.4.Significance and Use4.1 The advantages of the Clarke-Bumpus plankton samplerare as follows:4.1.1 It will s
6、ample a discrete depth or multiple depths,depending upon the sampling design.4.1.2 It is a slow to medium speed sampler requiring atowing speed of 3 to 5 knots.4.1.3 The sample size can be easily controlled.4.1.4 The sampler is light-weight and can be used withoutauxiliary equipment.4.1.5 It has a r
7、elatively high filtration efficiency factor of0.88.4.1.6 It is a versatile sampler and can be used in all but theshallowest waters.4.1.7 The flowmeter records the amount of water that passesinto the net.4.1.8 Overspill of water at the mouth of the net due toexcess speed of towing is of minimal conse
8、quence.4.2 The disadvantages of the Clarke-Bumpus plankton sam-pler are as follows:4.2.1 The flowmeter requires frequent maintenance includ-ing calibration and lubrication.4.2.2 It is not suitable for use in very small areas or shallowwaters.4.2.3 Because of the use of a net as a filtration material
9、,thesample is semiquantitative.4.3 There are several special considerations that shall beobserved when using a Clarke-Bumpus sampler.They are asfollows:4.3.1 The flowmeter should be calibrated and servicedfrequently to ensure efficient and accurate operation.4.3.2 The sampler is relatively fragile,p
10、articularly theclosing device and flowmeter.This necessitates careful deploy-ment and recovery procedures.4.3.3 Following each collection,the net must be thoroughlywashed.4.3.4 Special attention must be given to the strength of thecable and its attachment to avoid loss of the sampler.4.3.5 The sampl
11、er should not be used in beds ofmacrophytes,in waters containing submerged objects,or closeto the bottom.4.3.6 The net should be inspected frequently for pin-sizeholes,tears,net deterioration,and other anomalies.4.3.7 Following use,the wet net should be suspended fulllength in air and in subdued lig
12、ht and allowed to dry.5.Apparatus5.1 The Clarke-Bumpus plankton sampler,Fig.1,consistsof a metal frame in which a plankton net is attached at themouth and at the cod end.The sampler is available in threesizes:120 mm,200 mm,and 300 mm.The most widely usedsize is the 200-mm diameter net,which reported
13、ly has more1This 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 October 2012.Originallyapproved in 1982.Last previous edition approved in 2004 as D4134 82(20
14、04).DOI:10.1520/D4134-82R12.2For 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
15、Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 efficient trapping characteristics.A metal tube at the mouth ofthe net is fitted with a digital flowmeter from which the volumeof water filtered can be calculated.The mouth also contains ashutter device that effectively opens an
16、d closes the net permit-ting the collection of samples from discrete depths.The shutteris opened by a messenger,and closed by a second messenger.The sampler usually is attached to a towing cable and itshorizontal orientation is maintained by positioning veins at-tached to the side of the sampler frame.Several samplers canbe strung on a single cable for simultaneous sampling atvarious depths.The frame generally is constructed of stainlesssteel and the entire sampler weighs about 14 kg.6.Procedure
