Presentation of Verified Algal Taxa as Reference Sources - Phase II

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1 University of Arkansas, Fayetteville Technical Reports Arkansas Water Resources Center Presentation of Verified Algal Taxa as Reference Sources - Phase II Richard L. Meyer University of Arkansas, Fayetteville Follow this and additional works at: Part of the Fresh Water Studies Commons, Hydrology Commons, Soil Science Commons, and the Water Resource Management Commons Recommended Citation Meyer, Richard L Presentation of Verified Algal Taxa as Reference Sources - Phase II. Arkansas Water Resources Center, Fayetteville, AR. PUB This Technical Report is brought to you for free and open access by the Arkansas Water Resources Center at ScholarWorks@UARK. It has been accepted for inclusion in Technical Reports by an authorized administrator of ScholarWorks@UARK. For more information, please contact scholar@uark.edu, ccmiddle@uark.edu.

2 PRESENTATION OF VERIFIED ALGAL TAXA AS REFERENCE SOURCES - PHASE II Richard L. Meyer Department of Botany & Microbiology University of Arkansas Fayetteville, AR Publication No. 150 June,1990 Technical Completion Report Research Project G Arkansas Water Resources Research Center University of Arkansas Fayetteville, Arkansas AWRRC A rkansas W ater Resources Research Center Prepared for United States Department of the Interior

3 PRESENTATION OF VERIFIED ALGAL TAXA AS REFERENCE SOURCES - PHASE II Richard L. Meyer Department of Botany & M icrobiology U n ive rsity of Arkansas F a y e tte v ille, AR Inform ation Management Completion Report P roject G * The research on which th is report is based was financed in part by the United States Department of the In te rio r as authorized by the Water Research and Development Act o f 1984, (P.L ). Arkansas Water Resources Research Center U n ive rsity of Arkansas 113 Ozark Hall F a y e tte v ille, Arkansas P ublication No. 150 June, 1990 Contents of th is p u b lica tio n do not necessarily r e fle c t the views and p o lic ie s o f the U.S. Department of the In te rio r, nor does mention of trade names or commercial products c o n s titu te th e ir endorsement or recommendation fo r use by the U.S. Government. The U n ive rsity of Arkansas, in compliance w ith federal and state laws and regulations governing a ffirm a tiv e action and nondiscrim ination does not discrim inate in the recruitm ent, admission and employment of students, fa c u lty and s ta ff in the operation of any of it s educational programs and a c t iv itie s as defined by law. Accordingly, nothing in th is p u b lica tio n should be viewed as d ire c tly or in d ir e c tly expressing any lim ita tio n, s p e c ific a tio n or d iscrim in a tio n as to race, re lig io n, color or national o rig in ; or to handicap, age, sex, or status as a d is abled Vietnam-era veteran, except as provided by law. In q u irie s concerning th is p o lic y may be directed to the A ffirm a tiv e Action O ffic e r.

4 ABSTRACT PRESENTATION OF VERIFIED ALGAL TAXA AS REFERENCE SOURCES - PHASE II The focus of th is research p ro je c t was to continue the development of a photographic system which would record liv in g organisms using various forms o f lig h t microscopy w ith co rre ct color and w ith arrested movement. These demands d ic ta te the use of an e le c tro n ic fla sh source w ith metering and control system located in a p o sitio n fo llo w in g the passage of the lig h t through the o p tical tr a in. The system developed uses o ff-th e -s h e lf components with a m odified flashtube holder which po sitio n s the tube in the axis of the lig h t beam between the f ie ld and i r i s diaphragm. The lig h t is measured o ff- th e - film so th a t lig h t from the microscope and fla sh are combined. The fla sh is quenched and shutter closed based upon the combined reading. The second phase of the research p ro je c t concentrated on (1) improving the a d a p ta b ility of the equipment to various microscopes, (2) te s tin g the system under various lig h tin g conditions, and (3) producing high q u a lity micrographs of selected v e rifie d taxa. The micrographs w ill be incorporated in to an e x is tin g ecological data base of the algae of Arkansas. Many of the organisms are ubiquitous. Therefore, micrographs are useful fo r comparison w ith other sources as well as serving as a v e rifie d reference resources of Arkansas taxa. Richard L. Meyer Completion Report to the U.S. Department o f the In te r io r, Geological Survey, Reston, VA, June Keywords --A lg a e /B io in d ica to rs/d a ta Analysis/W ater Q uality Standards i

5 TABLE OF CONTENTS Page A bstract... i Acknowledgements... i i i In tro d u ctio n... 1 A. Purpose and O bjectives... 2 B. Related Research and A c tiv itie s... 3 Methods and Procedures... 4 P rin cipa l Findings and S ignificance... 5 Conclusions... 8 L ite ra tu re Cited... 8 i i

6 ACKNOWLEDGEMENTS The co n sulta tio n, h e lp fu l suggestions and able assistance of the graduate students in the Phycology Laboratory was valuable in developing and te s tin g the photographic apparatus, as well as the confirm ation o f id e n titie s o f several o f the taxa. The support o f the U.S. Department o f the In te r io r, Geological Survey, who provided the funds, and Dr. Kenneth Steele, D ire cto r, Arkansas Water Resources Research Center, is g re a tly appreciated. The assistance o f Mrs. G lo ria Wood, Mrs. Pauline M ueller and Mrs. Melpha Speak are g r a te f u lly acknowledged. i i i

7 INTRODUCTION The only reference source fo r the id e n tific a tio n o f freshwater algae w ith a p p ro p ria te ly colored illu s tr a tio n s fo r the United States is by Wolle in have included lin e drawings. Most o f the subsequent references Some o f these include illu s tr a tio n s w ith cytoplasmic d e ta il, w hile others are only s ilh o u e tte s. Certa in te x ts and a r tic le s may include monochromatic micrographs of fix e d, d rie d, cleared, or treated organisms. The major taxonomic references containing s tip p le d drawings are in Russian, German and P olish. Although s tip p le d drawings may present a three- dimensional view o f the organisms, they lack the tru e color and shadings o f the cytoplasmic in clu sio n s, i.e. p la s tid s, stigma, nucleus, storage products, spores, e tc. Most photographic techniques are lim ite d by the in te n s ity of the lig h t source and therefore require extended exposure times. Intense lig h t sources tend to modify or k i l l the c e lls due to heating or photodegradation. Newer methods of microscopy, i.e. phase-contrast, Nomarski d iffe r e n tia l co n tra st, and other systems, pass less lig h t to the film plane and exposure time increased. These extended exposure times prevent capture o f g lid in g a c tiv ity and fla g e lla r movement. Most m o tile c e lls (ve geta tive, zoospores or gametes) are q u ite small and e r ra tic in th e ir rapid movement. Also, m o tile c e lls are very d i f f i c u l t to photograph because th e ir movement is exaggerated by the m a g n ific a tio n o f the microscope. 1

8 The requirements necessary fo r the successful photomicrography o f liv in g algae include tru e p resen tatio n o f the p la s tid pigmentatio n, precise representation o f c e llu la r in clu sio n s, and a rre stin g the motion o f the fla g e lla as w ell as the in ta c t c e ll or colony. These c r ite r ia can be met by p o s itio n in g an e le c tro n ic fla s h tube in the axis o f the microscope lig h t beam. Systems developed earlie r by L e itz fo r th e ir Ortholux microscope have successfully demonstrated th a t the fla s h could be centered in the beam between the f ie ld and i r i s diaphragm. However, th is system did not include automatic quenching o f the fla s h outpu t. A. Purpose and O bjectives. The long-term o b je c tiv e o f the research is to develop a v e r i fie d photographic record o f algae from ecoregions, communities and subcommunities o f algae w ith in Arkansas. In order to accomplish th is o b je c tiv e, special equipment was designed and tested. The require d f ilm plane quenched fla s h c o n tro l systems are not a v a ilable com m ercially fo r microscopes. However, components are a v a ilable via professional and advanced amateur cameras. The f i r s t phase o f th is research p ro je c t was to modify and adapt these components fo r attachment to various microscopes. The objectives of the second phase included (1) the improved a d a p ta b ility o f the u n it to f i t various microscopes, (2) te s tin g the developed system under various lig h tin g conditions, and (3) producing high q u a lity micrographs o f selected a lg a l taxa. 2

9 B. Related Research and A c t iv it ie s Algae were co lle cte d from a d ditional sampling s ite s and new taxa were added to our e x is tin g data base. The developed u n it was applied to develop a photographic record o f the midwestern species, v a rie tie s and forms o f the genus Pleurotaenium (Desmi- diaceae). In a d d itio n, selected taxa o f coccoid green algae, cyanophytes, as well as fla g e lla g e d and rhizopodial chrysophytes were photographed. These new images are included w ith in an e x is t ing c o lle c tio n and are cross-referenced w ith a taxanomic data base. New film s have become a va ila b le during the research period. Minimal inform ation fo r microscopic applica tio n s was a va ila b le. Of p a rtic u la r in te re s t was the new Kodak Ektar 25 color p rin t film. This film has e xce lle n t colo r balance (d a y lig h t) with extremely fin e grain s tru c tu re. The images can be enlarged up to 35 times w ith acceptable re s u lts as e ith e r colo r or black/w hite p rin ts. The a p p licatio n o f high re solu tio n color p r in t film is very desirable fo r developing a reference source which can be re a d ily copied, annotated and d is trib u te d. Other tested film s include Kodak Ektachrome HC 100 and s im ila r Fuji products. These film s produce p o s itiv e images fo r projectio n. Films o f higher speed tend to produce lower re s o lu tio n, but may be desirable fo r flu o re sce n t plus fla s h montague images. 3

10 METHODS AND PROCEDURES Careful analysis of the characteristics of several available amateur and professional 35mm camera systems were conducted. C rite ria for selection of components to be adapted and modified were developed. These included: 1) o ff-th e -film or equivalent flash controlling c irc u itry, 2) flash units which can be extended from the camera body, 3) dissectable flash unit which w ill permit disessembly and m odification, 4) dampened shutter closure to m inimize camera movement and disturbance of the specimens, 5) a v a ilable microscope adapters, and 6) matching photo eyepieces fo r varying focal lengths of microscope objectives. An additional desirable characteristic includes compatabil ity with mounts of other photomicrographic and video equipment. The equipment chosen for modification, adaptation and testing which met a ll of the above c rite ria were Olympus OM 35mm camera components. Camera bodies from the OM-2 series or more recent models contain o f-th e -film sensing c irc u itry. Several flash units are compatable with th is body, but the Olympus T Power Control 1 flash unit has a detachable flash head (T 28). This control unit can operate on self-contained batteries or with an external power source. The m odification and adaption phase concentrated on the modifica tio n of the flash head to f i t existing microscopes. The flash tube located between the fie ld diaphragm and condensor has given sa tisfa cto ry results and permits the flash u n it to be transferred 4

11 to various microscopes without special adaptation. The flash head was modified by introducing an a xia lly located 2 cm aperature in the head body. Non-essential components were removed from the head and the power/control cable was moved from the posterior surface to a lateral position. These modifications retained the parabolic re fle cto r, but permitted the microscope lamp beam to pass through the housing and sim p lifie d furthe r adaption to various microscopes. head is under development. A simple holder for the modified With further experimentation, i t may be possible to develop a universal adaptor with an adjustable, self-centering clamping mechanism. PRINCIPAL FINDINGS AND SIGNIFICANCE Available microflash units for microscopes lack o ff-th e -film c irc u itry to control the combined lig h t imput from the microscope illum ination and flash sources. Most of the units, therefore, lack the a b ility to readily measure various modes of illum ination, i.e. darkfield, b rig h tfie ld, phase-contrast and d iffe re n tia l interference contrast. Therefore, extensive experimentation is necessary to develop fixed combinations of illum ination intensity and flash in tensity/duration to produce satisfactory results. The developed system described here uses an o ff-th e -film metering c irc u itry, which senses the total lig h t input to the film and quenches the flash (cf. Meyer, 1989). This system measures lig h t from a ll sources, both the the microscope lamp and the flash 5

12 tube. I t accomodates variations in modes of illum ination as well as density of the specimen. The combined exposure is accomplished by setting the camera shutter speed for a shorter duration than required for correct exposure by the microscope lamp only. The microscope illum ination can be reduced in intensity as well as from a reflected or fluorescent source. The additional lig h t is from the flash source. The duration of th is constant intensity source is monitored and controlled by the camera. The flash duratio n is controllable from 1/40,000 to 1/10,000 sec. The constructed system has been tested on microscopes containing b rig h tfie ld, darkfield, phase-contrast and d iffe re n tia l in te r ference contrast illum ination. The intense illum ination from the flash unit permits the use of film s with greater resolution but of lower film speed. Thus, higher q u a lity images are recorded. This system e ffe ctive ly stops organism and organelle motion. Flagellar action is arrested at a ll levels of magnification and with various illum ina tion systems. With the flash system, specimens can be observed and studied at lower intensities/heat; thereby, reducing ce llu la r damage and without the introduction of destructive or non-destructive adjuncts. The system was used to examine twenty (20) species, varieties and forms of the genus Pleurotaenium. This taxon was photographed at various levels of magnification, 5 to l,250x, with b rig h tfie ld, phase-contrast and d iffe re n tia l interference microscopy. Sim iliar techniques were used with representatives of the coccoid greens, 6

13 euglenoids, desmids, bluegreen algae and several motile and amoeboid chrysophytes. Most of the micrographs were recorded on low speed, high resolu tio n positive color film s. These provide high q u a lity projection images. Detailed analysis may be achieved by viewing through a dissecting microscope. I f daylight corrected film s are used, the resultant colors closely matched those of the specimen. However, some daylight film s may be weak in the yellow range of the spectrum while others emphasize the blues. For example, Kodak Ektachrome HC 100 provides high speed, moderate resolution, but enhanced blues with increased contrast. These characteristics may be valuable when photographing fluorescent images. The use of color correcting f ilt e r s may sig n ifica n tly reduce film speed to that of higher resolution color balanced film s. The a va ila b lity of high resolution, but low speed, color p rin t film has added a new dimension to the research. Kodak's Ektar 25 (ISO 25/15 ) produces fine grain color prints with excellent color balance. The negatives can be enlarged up to 35x for either color or black/white prints. This new film and color prints are ideally adapted to the development of a verifie d reference source of algae. The p rin ts are easier to reproduce, do not require projectio n equipment and can be annotated to h ig h lig h t spe cific characte ris tic s. Also, monochromatic prints can be incorporated into s c ie n tific publications. Therefore, color prints and positive images w ill be produced as a component of the reference resources. 7

14 CONCLUSIONS The u tiliz a tio n of o ff-th e -sh e lf components to produce a auto-regulated flash system adaptable to various microscopes and illu m in a tio n systems has been successful. The system is functional and has surpassed the goals of the in itia l phase of the research. High resolution, color correct images of motile organisms, zoospores or gametes have been produced using a ll illum ination methods. The system is now being used to develop an extended collection of images. Also, newer film types have been tested and the addition of high resolution color p rin t film has added a new dimension to the development of the reference resource. LITERATURE CITED Meyer, Richard L., Presentation of V arified Algal Taxa as Reference Sources. Arkansas Water Resources Research Center. Publication No University of Arkansas, F a ye tte ville, AR. Wolle, F., The Fresh-Water Algae of the United States. The Comenius Press. Bethlehem, PA. p