ASTM_D_4557_-_85_1995.pdf

Designation:D 4557 85(Reapproved 1995)Standard Practice forCollecting Benthic Macroinvertebrates with Surber andRelated Type Samplers1This standard is issued under the fixed designation D 4557;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(e)indicates an editorial change since the last revision or reapproval.1.Scope1.1 This practice covers the procedures for obtaining asample of macroinvertebrates inhabiting mud,sand,gravel,orrubble substrate.1.2 The device is restricted to use in shallow streams orshallow areas of rivers,and it depends on a water velocity ofnot less than 0.05 m/s to wash the sample into a net.1.3 This standard does not purport to address all of thesafety concerns,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.For a specifichazard statement,see 6.8.2.Referenced Documents2.1 ASTM Standards:D 1129 Terminology Relating to Water2D 4556 Guide for Selecting Stream-Net Sampling Devicesfor Collecting Benthic Macroinvertebrates33.Terminology3.1 Definitions:3.1.1 For definitions of terms used in this practice,seeTerminology D 1129.4.Summary of Practice4.1 The Surber sampler consists of two 30.5-cm frames,hinged together;one frame rests on the substrate,the otherremains upright and holds the nylon net.The sampler ispositioned with its net mouth open,facing upstream.4.2 When in use,the two frames are locked at right angles,one frame marking off the area of substrate to be sampled andthe other frame supporting a net to strain out organisms washedinto it from the sample area.4.3 Modification of the Surber sampler to overcome some ofthe limitations of its use(for example,loss of organisms due tobackwash)has resulted in the design and construction of anumber of related sampling devices,such as the four-sided(enclosed)portable invertebrate box sampler,the cylindricalHess sampler,the cylindrical Hess stream bottom sampler,andthe cylindrical stream-bed fauna sampler.4.4 Operation of the portable invertebrate box,Hess,Hessstream bottom,and stream-bed fauna samplers are similar tothe Surber sampler.4.5 The net used to collect macroinvertebrates can vary inmesh size,length,taper,and material,for example,canvas,taffeta,or nylon monofilament.4.6 The net is usually made of nylon,and a variety of meshsizes is available.The mesh size used will depend on theobjectives of the study.A mesh size of 0.35 mm,for example,will retain most instars of aquatic insects.4.7 While a smaller mesh size might increase the number ofsmaller invertebrates and young instars collected,it will clogmore easily and exert more resistance to the current than alarger mesh,possibly resulting in a loss of organisms due tobackwashing from the sample net.4.8 It should be noted that these samplers are specific formacroinvertebrates,and that many of the micro-components ofthe benthos will not be collected.4.9 The Surber,portable invertebrate box,Hess,Hessstream bottom,and stream-bed fauna samplers sample an areaof 0.1 m2.4.10 The polyester foam base of the portable invertebratebox sampler conforms to a variety of substrates to prevent theloss of organisms from beneath the sampler.The Hess,Hessstream bottom,and stream-bed fauna samplers can be“turned”into most sediment types to a depth of several centimetres.TheSurber sampler rests on the surface of most sediments.4.11 When sampling is completed,the net of the portableinvertebrate box sampler slides out for cleaning or exchangewith a different net.Hess-type samplers may have a mason jarring and an adapter with a fixed or removable cloth net bucket.4.12 These samplers are designed for use in shallow,flow-ing waters.4.13 These samplers cannot be used as efficiently in still ordeep water.4.14 These samplers are best used in water of 30.48-cm(1-ft)depth or less.1This practice is under the jurisdiction of ASTM Committee E47 on BiologicalEffects and Environmental Fate and is the direct responsibility of SubcommitteeE47.03 on Terrestrial Assessment and Toxicology.Current edition approved Dec.27,1985.Published May 1986.2Annual Book of ASTM Standards,Vol 11.01.3Annual Book of ASTM Standards,Vol 11.05.1Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959,United States.4.15 If the water depth is greater than 30.48 cm(1 ft),benthic organisms may wash over the top of the net rather thaninto it.4.16 These samplers do not provide quantitative samplesconsistently,and the efficiency of the sampling device dependson the experience and ability of the user.4.17 While there can be large sampling errors associatedwith their use by an inexperienced operator,these samplers canprovide data which are accurate and comparable if they areused consistently