of the James River Basin, Virginia I. Zygnemataceae and Oedogoniaceae Author(s): Bernard Woodson and G. W. Prescott Source: Transactions of the American Microscopical Society, Vol. 80, No. 2 (Apr., 1961), pp. 166- 175 Published by: Wiley on behalf of American Microscopical Society Stable URL: http://www.jstor.org/stable/3223905 Accessed: 04-01-2016 20:08 UTC

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This content downloaded from 132.248.28.28 on Mon, 04 Jan 2016 20:08:53 UTC All use subject to JSTOR Terms and Conditions ALGAE OF THE JAMES RIVER BASIN, VIRGINIA I. ZYGNEMATACEAE AND OEDOGONIACEAE

BERNARD WOODSON AND G. W. PRESCOTT Virginia State College, Petersburg; Michigan State University, East Lansing

This report is the first of several which we propose to make from studies of the algal flora of Virginia. The initial study, made in 1956, was a survey of the of the James River Basin. Field work included the taking of limnological and ecological data, as well as year-around qualitative samplings of the algae at nearly 100 selected stations. The ecological and descriptive data which follow will acquaint the reader with the general topography of the area covered in the first investigation, as well as some idea of the nature of the soils drained by the James River. We lis,t and illustrate herein the identifiable species of the Zygnemataceae and Oedogoniaceae which are new records for the State of Virginia.

INTRODUCTION The James River has its headwaters in the mountains of the Alleghanv Plateau in Craig, Alleghany, Bath, and Highland Counties of Virginia. It is formed by the confluence of the Jackson and Cowpasture Rivers, traverses the state, and enters Chesapeake Bay through Hampton Roads. It is the, largest drainage basin in the state, including an area of 6,757 square miles west of Richmond. The principal tributaries of the James River west of the Blue Ridge Mountains are the Maury River from the north, and Craig and Catawba Creeks from the south. The river cuts through the Blue Ridge Mountains near Balcony Falls below Clifton Forge. East of the mountains the principal tributaries from the north above Richmond are the Pedlar, Buffalo, Rockfish, Hardware, and Rivanna Rivers; and from the south are the Slate and Willis Rivers. The Appomattox River from the south and the Chickahominy River from the north enter the James below the upper limits of tide-water. The James River passes through three areas of different geologic character. West of the Blue Ridge Mountains it drains an area of sand- stone, shale, and limestone formations. East of the mountains it enters an area of hard crystalline rock, whereas east of the fall zone it traverses the sands and clays of the coastal plain. The tributaries in each of these areas naturally determine, in part, the chemical nature of James River water. Many of the tributaries west of the Blue Ridge are sustained by large springs, which generally flow from or through limestone formations. Consequently, dissolved matter in the water consists mainly of the bicarbonates of calcium and magnesium. The principal tributaries to the James River above Buchanan are the Jackson and Cowpasture Rivers and Craig Creek. The principal mineral constituents are the bicarbonates of calcium and magnesium. At Buchanan, the James River drains an area of 2,084 square miles. Reports by the State Conservation Department (1947-1948) on the 166

This content downloaded from 132.248.28.28 on Mon, 04 Jan 2016 20:08:53 UTC All use subject to JSTOR Terms and Conditions JAMES RIVER ALGAE 167 condition of the James River drainage at this point show the dissolved mineral matter to be composed mainly of calcium, magnesium, bicar- nates, and sulfates. Waste materials enter the Jackson River between Falling Springs and its junction with the Cowpasture River, and the resultant pollution is attested by a slight increase in color and chloride-content of the James River at Buchanan, over that of the Jackson River at Falling Springs and the Cowpasture River near Clifton Forge. Between Buchanan and Bent Creek the principal tributaries to the James are the Pedlar and Maury Rivers. The mineral content of the water of the Maury River near Buena Vista is less concentrated than that of the James River at Buchanan, but contains more magnesium and is accordingly harder. Its effect on the James River is a decrease in the concentration of dissolved matter. The James River at Bent Creek has a drainage area of 3,671 square miles. The mineral content of the water at this point is less concentrated and hence softer than at Buchanan. This is mainly caused by the soft water of low mineralization which enters the river east of Craig Creek. The waters of all tributaries to the James River between the Bent Creek and Richmond stations are low in mineral-content and are soft. The Rockfish, Hardware, Slate, Rivanna, and Willis Rivers all drain an area of crystalline rocks. The Buffalo River, which joins the James below Bent Creek, has a high sulphate-content and is slightly acid at times because of industrial wastes that enter the stream above Norwood. The water is soft, however, and its total effect on the James River is the maintenance of an average sulphate-concentration in the water at Rich- mond at the same level as found at Bent Creek. The James River at Richmond drains an area of 6,757 square miles. The report made by the State Conservation Department (1947-1948) shows that the water of the James River at Richmond has much less concentration than at Bent Creek. The decrease in mineralization at this station is in accord with the tributary inflow indicated above. The Appomattox and Chickahominy Rivers, as previously mentioned, are the main tributaries of the James below Richmond, making their entrance below the upper limits of tide-water. The former rises in Appomattox County and flows into the James at City Point. Its course parallels that of the James River until it reaches the fall line, where it turns northeast. The Appomattox River has a drainage area above Farmville of 306 square miles and above Mattox of 745 square miles. It flows over areas of crystalline, siliceous rocks; therefore, the principal characteristics of the water are its siliceous nature, its high degree of dilution, and its softness. The quantities of dissolved substances and degree of hardness at the headwaters are similar in the lower reaches. The Chickahominy River has a drainage area of 249 square miles above Providence Forge. It rises in Hanover County, flows southeast, traversing the sands and clays of the Coastal Plain, and empties into the James River at During Point. The principal characteristics are its low mineral content and extreme softness. The water has considerable color, which is due partly to inflow from swamp areas. In Table I we list only the streams in which representatives of the Zygnemataceae and Oedogoniaceae occurred. The plate of illustrations depicts only the identified species; namely, those which were found in a reproductive state and which are new records for Virginia.

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DESCRIPTION OF HABITATS Below are brief descriptions of the habitats at those stations repre- sented by the algal species listed herein. See Map. Station 6. Fine Creek. This is a slowly flowing stream with a sandy bottom. It is slightly acid (pH 6.8) with a very low CaCO3- and NO3- content. Spirogyra Cleveana and echinospermum occurred here. Station 7. Beaverdam Creek. A relatively slow, rocky stream. The pH is neutral to slightly basic (pH 7.1) and the CaCO3 and NO3 are low. This habitat contained the highest number of species of all stations examined, Spirogyra aplanospora, Sp. Cleveana, Sp. mirabilis, and Sp. semiornata. Station 13. Falling Creek. A relatively swift, rocky stream. The pH is neutral to slightly acid (pH 6.5), and the CaCO3- and NO3-contents are moderately low. Algal species found here are Spirogyra aplanospora and vegetative forms of Mougeotia spp. and Oedogoniumspp. Station 24. Chickahominy River. This is a slow stream with a sandy bottom. The NO3- and CaCO3-content are moderately low. Only vegetative forms of Mougeotia and Spirogyra were found here. Station 45. Rivanna River. A relatively swift, rocky stream. The pH is neutral to slightly acid (pH 7.0) and the CACO3 and NO3 are low. Spirogyra crassa is the only identifiable species although vegetative forms of Oedogoniumand Mougeotia occur. Station 52. Appomattox River. This is a swift and rocky stream in its headwaters, but at Petersburg where most of our collections were taken, it is retarded by a dam which supplies power to the city. The pH is neutral to slightly acid (pH 7.0), and the CaCO3- and NO3-contents are quite low. At the time of the survey (1956) the stream was highly polluted with sewage. The species identified at this station were collected in quiet pools and back washes along the stream. There were large numbers of vegetative and unidentifiable species, but recognizable are Oedogoniumminus, Spirogyra insignis and Sp. mirabilis. Station 58. Slate River. This is a swiftly flowing, rocky (slate) stream, and apparently is polluted. The pH is neutral to slightly basic (pH 7.2), with the CaCO3- and NO3-contents moderately low. The only species found was Spirogyra crassa. Station 65. Catawba Creek. This is a slow, muddy stream with a basic pH (pH 7.5). The CaCO3- and N03-contents are relatively high. The stream showed evidence of being polluted by a large amount of dissolved matter. Here profuse growths were found of Spirogyra crassa. Station 67. Craig Creek. A swift, rocky, mountain stream with a large number of calciphilic plants present (Chara, Elodea, Potamogeton, et al). In our collections we found only vegetative forms of S pirogyra, and Zygnema insigne. Station 76. Pedlar River. This, too, is a swift, rocky, mountain stream with a pH that is slightly acid to neutral (pH 6.9), and with a low CaCO3- and NO3-content. Only vegetative, floating growths of Oedogoniumspp. were found here. Station 77. Buffalo Creek. A swiftly flowing, rocky, mountain stream that is neutral to slightly basic (pH 7.2) with a very low CaCO3- and NO3-content. The stream showed evidence of being highly polluted, with a profuse growth of blue- on the rocks. Station 78. Jackson River. This is another swift, rocky, mountain

This content downloaded from 132.248.28.28 on Mon, 04 Jan 2016 20:08:53 UTC All use subject to JSTOR Terms and Conditions 170 BERNARD WOODSON AND G. W. PRESCOTT stream, slightly basic (pH 7.6) and with a moderately high CaCO3-content, but a low NO3-content. The river is highly polluted by paper-mill wastes at Covington. The species present were mostly vegetative forms but Spirogyra communis was identified. TAXONOMICLIST Measurement ranges include the limits which have been reported in descriptions of the species. We give here only the principal taxonomic characters. Spirogyra aplanospora Randhawa 1938. (Figs. 2, 3) Vegetative cells 20-(26) u in diam., 40-(90) u long; end walls plane; chloroplast one, making three to six turns; fertile and sterile cells inflated irregularly; reproduction only by ovoid to globose aplanospores, 24-30 p in diam., 30-50 u long; median spore wall brown, smooth. (Stations 10, 12). Previously reported only from India. Transeau (1951) has suggested that this is possibly an 'ecological form' of Sp. mirabilis (Hass.) Kuetz. Spirogyra Cleveana Transeau 1934. (Fig. 7) Vegetative cells 34-40,u in diam., 140-465 t long, end walls replicate; chloroplast one (rarely two), making three to six turns; conjugation scalariform by tubes from both gametangia; zygospore ovoid to cylindric- ovoid, 34-50 t in diam., 70-125 u long, outer spore wall hyaline but in two layers, the inner being coarsely scrobiculate, median spore wall smooth, yellow. (Station No. 12). Spirogyra communis (Hass.) Kuetz. 1849. (Fig. 11) Vegetative cells 18-26u in diam., 35-90 u long, end walls plane; chloroplast one, making 112 to four turns; conjugation scalariform by tubes from both gametangia; fertile cells not inflated; zygospore ellipsoid, 19-26 , in diam., 36-78 IA long, median spore wall smooth, yellow. (Sta- tion No. 7). Spirogyra crassa Kuetz. 1843. (Fig. 10) Filaments stout, feeling glassy to the touch; vegetative cells 140-165 I in diam., 126-330 u long, end walls plane; chloroplasts six to 12, making 12 to one turn; zygospore compressed-ovoid, 120-150 u in diam., 140-175 , long, median spore wall brown and finely reticulate.

EXPLANATION OF PLATE FIG. 1. Spirogyra insignis (Hass.) Kuetz. FIG. 2. Spirogyra aplanospora Randhawa FIG. 3. Spirogyra aplanospora Randhawa FIG. 4. Oedogonium echinospermum A. Braun FIG. 5. Zygnema insigne (Hass.) Kuetz. FIG. 6. Spirogyra semiornata Jao FIG. 7. Spirogyra Cleveana Trans. FIG. 8. Oedogonium echinospermum A. Braun; androsporangia FIG. 9. Spirogyra semiornata Jao FIG. 10. Spirogyra crassa Kuetz. FIG. 11. Spirogyra communis (Hass.) Kuetz. FIG. 12. Spirogyra mirabilis (Hass.) Kuetz. FIG. 13. Oedogonium minus Wittr.

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Specimens in this collection were vegetative (as is usually the condition) forming dense, dark green masses in quiet water of pooled streams. This is one of the few species of Spirogyra which can be identified in the non- reproductive state because of the large size and the number and arrange- ment of the chloroplasts. Transeau (1951) indicates that reproductive specimens are relatively rare, and points out that the original description of the plant was based on sterile material. In western United States (Montana, e.g.) this species is found commonly conjugating, forming extensive festoons over submerged aquatic plants. (Station Nos. 3, 6, 11). Spirogyra insignis (Hass.) Kuetz. 1849. (Fig. 1) Vegetative cells 39-42 u in diam., 150-590 A long; chloroplasts two to four, making 12 to 112 turns; conjugation both scalariform and lateral, both gametangia forming tubes; zygospore ellipsoid, 40-48 u in diam., 60-128 A long, median spore wall yellow-brown, smooth. (Station No. 2). Spirogyra mirabilis Kuetz. 1849. (Fig. 12) Vegetative cells 23-29 / in diam., 70-200 u long, end walls plane; chloroplast one, making four to seven turns; reproduction by ovate to ellipsoid aplanospores, 23-29 / in diam., 50-83,u long, median spore wall yellow-brown, smooth; scalariform conjugation rare; sporangia enlarged or inflated. (Station Nos. 2, 12). Spirogyra semiornata Jao 1935. (Figs. 6, 9) Vegetative cells 27-32 A in diam., 95-245 , long, end walls replicate; chloroplast one, making two to six turns; conjugation scalariform by tubes from both gametangia, fertile cells enlarged; zygospores ovoid, 35-46 u in diam., 61-106 , long, median spore wall yellow-brown, smooth. (Sta- tion No. 12). Although this species has been reported only from China, the taxonomic features agree with Jao's description. Zygnema insigne (Hass.) Kuetz. 1849. (Fig. 5) Vegetative cells 26-32 ju in diam., 26-60 / long; conjugation scalari- form; zygospore formed in one of the gametangia, the receptive gametangia cylindric or enlarged; zygospores globose or subglobose, 27-33 . in diam., 27-35 ,t long, median spore wall yellow-brown, smooth. (Station No. 6). Oedogoniumechinospermum A. Braun in Kuetzing 1849. (Fig. 4) Nannandrous; gynandrosporous or idioandrosporous; vegetative cells cylindric, 18-30 ,u in diam., 45-130 u. long; oogonium ellipsoid-globose, opening by a median pore, 39-50 .t in diam., 41-57 ,u long; oospore globose or depressed-globose, the outer wall with short, sharp spines, 38-47 A in diam., 38-49 1u long; dwarf male plants 10-15 , wide, 26-55 p long; antheridium 6-12 tu in diam., 6-15 , long. (Station No. 8). Oedogoniumminus Wittr. 1875. (Figs. 8, 13) Macrandrous; monoecious; vegetative cells somewhat capitellate; walls spirally punctate, 9-13 u. in diam., 30-78 ,. long; oogonia solitary, globose or pyriform-globose, operculate, division median, 34-46 ,u in diam., 28-42 A long; oospore depressed-globose, 30-42 pi in diameter, 26-36 ,u long, not filling the oogonium, wall smooth; antheridium 9-13 , in diam., 3-5 u long. (Station No. 52).

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DISCUSSION Within an area as extensive as the James River Basin one would expect to find many more species of the Zygnemataceae and Oedogoniaceae than listed above. There are many factors that may determine the paucity of species and we shall discuss only a few. Time of Collection: We found many more species of the two families than listed, but these were in the vegetative, hence unidentifiable state. Smith (1950) states that the Zygnemataceae have a marked seasonal periodicity of sexual reproduction, and that each species seems to reproduce at a definite time of year. He further suggests that many species are seasonal in their reproductive habits (spring and summer forms). Smith (I.c.) also indicates that species of Oedogoniumusually are found in sexual reproduction in permanent bodies of water such as pools and ponds, rather than in flowing water, or if in streams the current is very sluggish. Blum (1956) suggests that most river filamentous algae reproduce mainly vegetatively. Hence identification and life cycles must be determined by culturing in the laboratory. Transeau (1916) has divided algae into seven classes on the basis of their periods of greatest abundance, the duration of their vegetative cycle, and the time of their reproduction. Species of Zygnemataceae and Oedogoniaceae are listed by him as spring annuals, summer annuals, and autumn annuals. Very few are listed as perennials or ephemerals. It is possible that our collections were made after or before the species under consideration had reached their reproductive condition. If this is true, then the number of species might have been greater had collections been more frequent, although stations were sampled at each season of the year. Softness of the Water: The majority of the streams exhibiting species of the two families considered were quite soft. Only two had a CaCO3- content above 61 ppm. It may be of interest to note here, however, that of all the 20 major streams sampled in this survey, only four had a CaCO3- content above 61 ppm. The fact that so many streams were relatively soft may be another explanation for the low numbers of forms observed since the Zygnemataceae, in the main, is basiphilic. Blum (I.c.) and Welch (1952) have suggested that neutral or slightly basic conditions appear to be necessary for the growth of most of the algal species inhabiting flowing water. Butcher (1949) has observed that waters high in lime-content tend to be rich in algae, other conditions being conducive. Reinhard (1931) cites the Minnesota River as a stream which contains abundant carbonates, producing an average volume of plankton that is six times that of the St. Croix River which is poor in carbonates, and contains humic acids. Foged (1948), Hustedt (1939), and Prescott (1951) have also indicated that slightly hard waters are more productive than soft. Nitrogen Content: The streams included in this report were relatively low in N03-content. Blum (1953), Butcher (1924), Kofoid (1903), and Pearsall (1923) have observed that nitrates are in more abundance at times of heavy rains or melting snow; thus, being at a high level during the winter and spring when streams are high, but plant growth greatly reduced (in our latitudes). Wade (1949) has correlated nitrate consumption with phytoplankton development. He has found that the lowest number of organisms were present when nitrites and nitrates were most abundant. This condition has been observed by many others and is related to the fact that nitrates become reduced as they are taken up by increasing plant

This content downloaded from 132.248.28.28 on Mon, 04 Jan 2016 20:08:53 UTC All use subject to JSTOR Terms and Conditions 174 BERNARD WOODSON AND G. W. PRESOCTT populations, the N-content again becoming high with the decrease of algal species in fall and winter. Sawyer (1944) for example found that inorganic nitrogen was reduced after bloom conditions had developed in Waubesa, Lake, Wisconsin. The most productive streams in our area of study had the lowest nitrogen-content. More information is needed to draw any generalizations relative to the rise and fall of the N-content in relation to the bulk and to the number of species in the algal population. It is possible that the Zygnemataceae and Oedogoniaceae (as well as other filamentous forms) do not compete well for nitrogen with the high plankton productivity here, hence are limited. Whitford (1960) has pointed out the relationship of current to the accessibility of nutrients which are low in concentration, the diffusable substances being carried away. Pollution: As listed in Table I, the streams which are polluted equal in number the unpolluted. Brinkley (1942), Butcher (1940), and Lackey (1942) have observed that in polluted streams the total number of species may be reduced; however, those species which can establish themselves are usually prolific. The density of both benthon and plankton may be reduced temporarily by large amounts of sewage. Butcher (1949) has

TABLEI

pH CaCO3 NO3 Pollution Rate of Flow StationStatin No. No. Below Above Low High Low High Slw - Slow Swift 7.2 7.27 72PPMppm PPMppm PMppm ppm +

Fine Creek...... 6 6.8 15 0.2 - X Beaverdam Creek... 7 7.1 19 0.24 X Falling Creek...... 13 6.5 47 0.13 + X Chickahominy Creek...... 24 6.4 49 0.09 - X Rivanna River...... 45 7.0 17 0.7 - X Appomattox River.. 52 7.0 27 0.35 + X Slate River ...... 58 7.2 19 0.23 + X Catawba Creek..... 65 7.5 154 1.4 + X Craig Creek...... 67 7.5 43 0.2 - X Pedlar River ...... 76 6.9 13 0.2 - X Buffalo Creek...... 77 7.2 24 0.25 + X Jackson River...... 78 7.6 83 0.3 + X observed also that if the organic matter is increased beyond an optimum amount the biota may be completely destroyed, the algae disappearing from certain portions of the stream. Many of the streams investigated in the James Basin were quite poor in the growth of both algae and higher aquatic plants-streams which were polluted by sewage and by industrial wastes. Current Rate: It has been observed that only certain algae will grow (and reproduce) in rapid water, and that usually these will grow much more luxuriantly where the current is very rapid than where there is little current. Whitford (I.c.) has discussed this relationship critically. He also found Oedogonium kurzii Zeller growing only in swift piedmont streams. Guimaraes (1950) observed that Brazilian waters of rapid streams are less productive than the larger, slow-moving rivers. It is apparent that flowing water presents a hazard for the development of plants in general. The swifter waters are usually devoid of higher aquatic

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plants, and only a few filamentous algae are able to survive. Cladophora is one genus that is well-adjusted to swift streams. In our survey it was observed that the swifter streams were a little less productive in number of algal species than the slower. The current-rate factor, in association with the other four conditions mentioned above may account for the paucity of species noted. Further studies, now in progress, on these and other waters in Virginia doubtless will disclose man- more algal species. Results of these studies will be summarized in later publications.

LITERATURE CITED

BLUM, J. L. 1953. The ecology of algae growing in the Saline River, Michigan, with special reference to water pollution. Doc. Theses, University of Michigan, ix-176 pp. 1956. The ecology of river algae. Bot. Rev., 22(5): 291-341. BRINKLEY, F. J. 1942. The effect of sewage from Nashville upon the plankton population of the Cumberland River. Jour. Tenn. Acad. Sci., 17: 179-183. BUTCHER,R. W. 1924. The plankton of the River Wharfe (Yorkshire). Naturalist, 6: 95-629. 1940. Studies in the ecology of rivers, IV. Observations on the growth and distribution of the sessile algae in the River Hull, Yorkshire. Jour. Ecol., 26: 210-223. 1949. Problems of distribution of sessile algae in running water. Verh. Inter. Ver. Theoret, Ang. Limnol., 10: 28-103. FOGED, N. 1948. Diatoms water courses in Funer. IV-VI. Dansk. Bot. Arkiv, 12-9): 1-55. GUIMARAES,J. R. A. 1950. Consideracoes sobre a capacidade biogenica des aquas. Rev. Inst. Animal (Sao Paulo), 1: 508-514. HUSTEDT,F. 1939. Diatomeen aus den Pyrenaen. Ber. d. Deutsch. Bot. Ges., 56: 543-572. KOFOID,C. A. 1903. Plankton studies. IV. Bull. Ill. State Lab. Nat. Hist., 6: 95-629. LACKEY,J. B. 1942. The effects of distillery wastes and waters on the microscopic flora and fauna of a small creek. U. S. Public Health Rep., 58: 253-260. PEARSALL,W. H. 1923. A theory of diatom periodicity. Jour. Ecol., 11(1): 165-183. PRESCOTT,G. W. 1951. Algae of the western Great Lakes region. Cranbrook Press. REINHARD,E. G. 1931. The plankton ecology of the upper Mississippi, Minneapolis to Winona. Ecol. Monogr., 1: 395-464. SAWYER,C. N. 1944. Investigation of odor nuisance occurring in Madison Lakes particularly Monona, Waubesa, Kegonsa from July 1943 to July 1944. Mimeogr. Rep. to Gov. W. S. Goodland. SMITH, G. M. 1950. The fresh-water algae of the United States. McGraw Hill Book Co. TIFFANY, L. H. 1937. Oedogoniales. Oedogoniaceae. N. Amer. Flora, 11, Part 1. 102 pp. New York Bot. Gard. TRANSEAU,E. N. 1916. The periodicity of fresh-water algae. Amer. Jour. Bot., 3: 121-133. 1951. The Zygnemataceae. Ohio State Univ. Press. WADE, W. E. 1949. Some notes on the algal ecology of a Michigan lake. Hydro- biol., 2(2): 109-117. WHITFORD,L. A. 1960. The current-effect and growth of fresh-water algae. Trans. Amer. Microsc. Soc., 79(3): 302-309.

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