Observations on the Ecology of Protozoa Associated
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OBSERVATIONS ON THE ECOLOGY OF PROTOZOA ASSOCIATED WITH SPHAGNUM DISSERTATION Presented in Partial Fulfillment of the Requirements for the Degree Doctor of Philosophy in the Graduate School of The Ohio State University By Peter Chacharonis, B. A., M. A The Ohio State University 1954 Approved by Advise TABLE OK CONTENTS INTRODUCTION...................................................... 1 HISTORICAL REVIEW................................................. 2 NATURE OK THE ENVIRONMENT......................................... iO Location and History of the Bog.............................. 10 Description of the Hog....................................... 11 Ecological Characteristics of the Bog....................... 12 Structure and Growth of Sphagnum............................. IB MATERIALS AND METHODS............................................. 21 General...................................................... ill Collections.................................................. 21 pH Determinations............................................ 23 Temperature Determinations................................... 24 Methods of Examination....................................... 25 Staining Methods............................................. 2b Quantitative Determinations.................................. iO OBSERVATIONS.................................................. 32 General..................... 32 Distribution and Relative Frequency of Protozoa............. 32 The Position of the Organisms on and in the Sphagnum plant... 4J Seasonal Observations........................................ 45 Associations................................................. 48 DISCUSSION......................................................... 50 Significance of Associations at Different Levels............ 50 Succession................................................... 54 Comparison of the Protozoa of Cranberry Hog with those Found by Other investigators.............................. 5b SUMMARY............................................................ 58 REFERENCES......................................................... bl APPENDUL........ bb PLATES............................................................. b9 i INTRODUCTION The unusual protozoan fauna characteristic of sphagnua bogs has been known for aany years, and nuseroni investigators have studied it. Very few, however, have studied the actual relationships that exist between various Protozoa and the sphagnua plant itself, and none have done so systeaatically. This has been attempted in the present study of Protozoa associated with sphagnua in an acid bog in central Ohio. Upon close investigation of the smterial, an entirely new type of ecological relationship has been observed. The Protozoa live not only in snail pools on the bog, or in water around the base of the plant, but also in a variety of locations on and in the sphagnum plant itself. The present investigation was suggested by Professor Wencel J. Kostir of the Department of Zoology and Entoaology, at the Ohio State University, to whoa 1 wish to express ay sincere appreciation for his suggestions and guidance, and the tine and interest he has given ae. I aa also deeply grateful to Dr. J. N. Wolfe for his assistance in the botanical aspects of this study, and to Dr. A. LsRoy Andrews for his identification of the sphagnua. Finally, 1 wish to thank the Ohio Acadeay of Science for financial assistance granted for travel to and froa Buckeye Lake. 1 HISTORICAL REVIEW The earlier workers who studied Protosoa froai sphagnum and other ■ossea (aamng them Dnjardin, 1852, Greeff, 18bt>, Bhrenberg, 1874, Maggi, 1688, Scourfield, 1897), did little no re than emwerate or describe certain species fron noss collections. This was also lsrgeljr true of Leidy, 1879, Penard, 1902, 1909, Cash, Wailes, and Hopkinson, 1905-1921, Wailes and Penard, 1911, whose works were primarily taxonomic and general in scope, but who gave considerable infomation on Protosoa associated with sphagnum. A review of the literature of the Protosoa fron sphagnim discloses three nain lines of study: 1) those papers, prinarily of a taxonomic nature, which yield some infonsetion concerning ecological relation ships ; 2) those papers which attest to classify the Protosoa into ecological associations; and 3) those papers, very few in number, which describe in detail certain species found on or in the sphagnum plant itself. Leidyvs monograph on Fresh-water Rhixopods of North Aswrica is probably the most outstanding of the taxonomic works which include Protosoa from sphagnum. Leidy not only described numerous species, but also stated under what conditions he collected them. Moreover* he pointed out that certain of these rhisopods frequently occur in loose associations and in relation to special environments. For example* he 2 stated that "usually the naked forms, and especially the larger ones, the Difflugias and the Arcellas, are found most frequently, abundantly and best developed, in the oose of bodies of water. The Euglyphas, Nebelas, and their nearer allies, are in like manner most frequent in the moist Sphagnum of bogs; " (1879: p. 12). In the sphagnum material examined by Leidy, 38 species of rhisopods were found, most of which were shell-bearing forms belonging to the order Testacea. Leidy*s collections were made chiefly in southeastern Pennsylvania and southwestern New Jersey; a few collections were made in Maine, Florida, Alabama, and Wyoming. Since Leidy1a day many Protosoa, particularly rhisopods, have been reported from sphagnum by investigators in many parts of the world. In 1900 Levender made a study of sphagnum collected from clefts or hollows between the rocks on the SluLren Islands off the coast of Finland, near Helsinki, and noted that the sphagnum harbored a characteristic fauna. He coined the term sphagnophilic for those forms which repeatedly appear in sphagnum and which, he said, seem to be "bound to it more or less closely." Penard (1902) in his Faune Rhisopodique du Bassin du Leman (Lake Geneva in Switserland) also reported rhisopods which live in sphagnum in that vicinity. In 1909 he made a further study of the rhisopods from various mosses, other than sphagnum, and concluded that their rhisopod fauna was essentially similar throughout, but varied from station to station according to differences in topography and climatic conditions. 3 Penard concluded that the rhisopods of Mosses in general consti tute a special fauna and should be divided into two aain categories. The first of these he called the banal fauna, or coaaonplace foras. This group included those species which are not restricted to aosses and do not possess structures or stages which facilitate their adapta bility to the aoss environaent. In this category he listed 19 species in the order of their frequency or relative abundance. The second group he called the characteristic fauna. This category contained those foras which possess, at soae tine in their life history, certain structures or stages which enable then to survive the varying conditions that nay arise in the aoss environaent. Penard listed 17 species as characteristic fauna of aosses other than sphagnua. In 1910 Heinis, working in the vicinity of Basel, in Switserland, listed M rhisopods which he found in sphagnua. Although Heinis aade no atteapt to classify these rhisopods ecologically, he pointed out that rhisopods in general are the typical sphagnophilic foras. In addition to this, Heinis also discussed briefly the association that exists between the fauna and the sphagnua plant itself. He found that rotifers, nesatodes, and Protosoa occurred on the outer cells of the sphagnua leaf, between the leaves and the stea, and around the decaying bottaa portion of the plant. Heinis concluded that the sphagnii suffered no ill effects fron this relationship, but that the aniaals or organisau benefited only through the space thus aade available to then for their life activities; he called this Rauaparasitisms. Kleiber (1911), working in the Black Forest in southwestern 4 Germany, and Steinecke (1913) in east Prussia (now a part of Russia), both studied the Protosoa of sphagnua bogs, and each attempted a classification of these foras according to types of habitat. The three publications of Harnisch (1925, 1927, and 1929) probably comprise the most complete account of the ecology of the shell-bearing rhisopods of sphagnum bogs. The first of these works presents a monographic treatment of the entire fauna in a large bog territory, the Seefelder at Reiners in Silesia (now a part of Poland). In a study of the bogs of this region, Harnisch found altogether 10 species of testacean rhisopods, and recorded their relative frequency. He also studied their frequency in relation to different amounts of moisture. From his observations and those of other investigators, Harnisch compiled a list of 16 purely sphagnophilic species, belonging to the genera Amphitrema. Arcella. Diffiueia. Euelvpha. Heleopera. Hyalosphe- nia. and We be la. He also designated certain forms as conditionally sphagnophilic and others as sphagnophobic. As conditionally sphagno philic he listed 45 species of Testacea, some of which have been marked as purely sphagnophilic by other authors. The sphagnophobic foras, on the other hand, were not identified to species, but included 23 genera of rhisopods, a few of which had been reported occasionally in sphagnum and are referred to as sphagnoxene (foreign to sphagnum, but present accidentally). Most of the sphagnophobic foras were referred