Meiobenthology: The Microscopic Fauna in Aquatic Sediments

338 Pages·1993·9.36 MB·English

by  Prof. Dr. Olav Giere (auth.)

Olav Giere
Meiobenthology
The Microscopic Fauna in
Aquatic Sediments
With 102 Figures and 20 Tables
Springer-Verlag Berlin Heidelberg GmbH
Prof. Dr. OLAV GIERE
Universităt Hamburg
Zoologisches Institut und
Zoologisches Museum
Martin-Luther-King-Platz 3
D-20146 Hamburg. Germany
ISBN 978-3-662-02914-5
Library of Congress Cataloging-in-Publieation Data. Giere. Olav. 1939-Meiobenthology : the microscopic
fauna in aquatie sediments / Olav Giere. p. em. Includes bibliographieal referenees (p. ) and index.
ISBN 978-3-662-02914-5 ISBN 978-3-662-02912-1 (eBook) 1. Meiofauna.
DOI 10.1007/978-3-662-02912-1
2. Benthos. 1. Title. QL120.G54 1993 592'.092 - de20 93-14010
This work is subjeet to copyright. All rights are reserved. whether the whole or part of the material is coneerned.
specifically the rights of translation. reprinting. reuse of illustrations. recitation. broadcasting. reproduction on
microfilm or in any other way. and storage in data banks. Duplication of this publication or parts thereof is
permitted only under the provisions of the German Copyright Law of September 9. 1965. in its current version.
and permission for use must always be obtained from Springer-Verlag. Violations are Iiable for prosecution under
the German Copyright Law.
© Springer-Verlag Berlin Heidelberg 1993
Originally published by Springer-V erlag Berlin Heidelberg New York in 1993
Softcover reprint of the hardcover 1s t edition 1993
The use of general descriptive names. registered names. trademarks. etc. in this publication does not imply. even
in the absenee of a specific statement. that such names are exempt from the relevant protective laws and
regulations and therefore free for general use.
Typesetting: Thomson Press (India) Ltd .. New Delhi
31/314 5/SPS-5 4 3 2 1 O - Printed on acid-free paper
To GABY
to whom lowe it all
Preface
Also bestimmt die Gestalt die Lebensweise des Thieres,
und die Weise zu leben sie wirkt auf aIle Gestalten
miichtig zuriick.
So, the shape of an animal patterns its manner of living,
likewise their manner of living exerts on the animals' shape
massive effects.
GOETHE 1806: Metamorphose der Thiere
Studies on meiobenthos, the motile microscopic fauna of aquatic sediments, are
gaining in importance, revealing trophic cycles and assessing impacts of anthro
pogenic factors. The bottom of the sea. the banks of rivers and the shores of
lakes contain higher concentrations of nutrients. more microorganisms and a
richer fauna than the water column. Calculations on the role of benthic organisms
reveal that the "small food web". i.e. microorganisms. protozoans and smaller
metazoans playa dominant role in the turnover of organic matter (KUIPERS et al.
1981). New animal groups - even of high taxonomic status - are often of
meiobenthic size and continue to be described. Two of the most recent animal
groups ranked as phyla. the Gnathostomulida and the Loricifera. represent
typical meiobenthos.
A textbook introducing the microscopic fauna of the sediments. their
ecological demands and biological properties, does not yet exist. despite the
significance of meiobenthos indicated above. The recent book entitled
Introduction to the Study of Meiofauna (eds. HIGGINS and THIEL 1988) gives valuable
outlines for practical investigation. and the Stygofauna Mundi. a monograph
edited by BOTOSANEANU (1986a), focusses on zoogeographical aspects mainly of
freshwater forms. but neither of these fulfils the needs for a comprehensive text
on the subject of meiobenthology.
It is the intention ofthis book to provide a general overview ofthe framework
and the theoretical background of the scientific field of meiobenthology. The
first of three major parts describes the habitat of meiobenthos and some of the
methods used for the investigation. The second part deals with morphological
and systematic aspects ofmeiofauna. and the third part reports on the meiofauna
of selected biotopes and on aspects of community and synecology ofmeiobenthos.
However. a monographic text cannot include an adequate survey of general
benthic ecology. or be a textbook on the zoology of microscopic animal groups.
The primary purpose of this text is to give an ecologically oriented scientific
basis for meiobenthic studies. Further advice for practical investigations is found
VIII Preface
in important compilations by HIGGINS and THIEL (1988) and HOLME and McINTYRE
(1984). Hence. aspects of sampling procedures and strategies. statistical treat
ment and fauna processing will be treated here in brief only. In these fields. the
present work should be considered a supplement to the books mentioned above
and will rather focus on some critical hints. methodological limitations. and a
few neglected practical aspects.
Writing this book was particularly difficult because the literature on
meiofauna is so widely dispersed in journals and congress proceedings and has
so rapidly increased in volume that a complete coverage is impossible. Regardless
of my efforts. therefore. there is no pretense of this text being absolutely compre
hensive. Where it is important for the general context. the major chapters of
the book may contain some overlap in details of information. This is deliberate.
and intends to provide the reader with chapters complete in themselves and to
avoid too many cross-references. While the scope of this book does not allow
for details on all aspects. the literature given in the text should enable the reader
to inquire further for more specific information. For this approach a fairly
extensive reference list is required. However. in order to maintain a readable.
coherent style. citation of specific references had to be restricted. Thus. the
Reference List of this text does not represent all the sources drawn upon in the
production of the book. Where appropriate. references compiled in a paragraph
"More detailed reading" are given at the conclusion of many sections and
chapters. They will serve as supplementary information and. hopefully. will
compensate for my own subjectivity.
The selection of topics and the emphasis given to them is admittedly subjective.
In particular. the brief treatment of freshwater meiobenthos (Chap. 8.2) by no
means reflects the exhaustive achievements and importance of this field of
meiobenthology. This book does not include the nanobenthos. since this
represents a micro biota completely different from the meiobenthos in its size
range. methodology and taxonomical composition (mainly prokaryotes. often
autotrophic protistans and fungi). Should there be incorrect or misunderstood
data reported in the text. I would be most grateful for information.
This book resulted from a series of lectures for advanced students given by
the author over a period of several years at the University of Hamburg. Studying
the tiny organisms living in sand and mud fascinated many of my students and
proVided the encouragement and persisting stimulus needed to write this book.
It will achieve its goal if it further promotes interest in the diverse and cryptic
microscopic world of meiobenthic animals. emphasizes their ecological
importance. both from a theoretical and practical view. and contributes to the
awareness that small animals often play a key role in large ecosystems which
are becoming increasingly threatened.
Acknowledgements. I am deeply obliged to Dr. Robert P. HIGGINS (Washington.
D.C.). who critically reviewed the entire text not only for linguistical flaws. My
thanks go to my graduate students who supported me in selecting figures and
designing graphs. I am grateful to several of my colleagues for their valuable
Preface IX
comments on parts ofthe text, also for providing me with manuscripts sometimes
still in press and for other helpful hints. It was my intention to include only
originals or redrawn figures. This was possible through the patient work of
A. MANTEL and M. HANEL (both Hamburg) for which I am most grateful.
Hamburg, July 1993 OLAV GIERE
Contents
1 Introduction.................. 1
1.1 What is Meiofauna? Definitions 1
1.2 A History of Meiobenthology .. 2
2 Habitat, Habitat Conditions and Their Study Methods 5
2.1 Abiotic Habitat Factors (Sediment Physiography) 6
2.1.1 Structure of Sediment Pores and Particles 6
2.1.2 Granulometric Characteristics . . 7
2.1.2.1 Grain Size Composition ......... . 7
2.1.2.2 Exposure and Sediment Agitation . . . . . 13
2.1.2.3 Permeability, Porosity and Pore Water Flow 14
2.1.2.4 Water Content and Water Saturation 15
2.1.3 PhYSico-Chemical Characteristics 17
2.1.3.1 Temperature 17
2.1.3.2 Salinity ............. . 18
2.1.3.3 pH Value ............ . 20
2.1.3.4 An Interacting Complex: Redox Potential, Oxygen
and Hydrogen Sulphide ..... 20
2.1.3.5 Pollutants . . . . . . . 26
2.1.4 Conclusions . . . . . . . . . . . . 27
2.2 Biotic Habitat Factors ..... 27
2.2.1 Dissolved Organic Matter (DOM) 28
2.2.2 Particulate Organic Matter 29
2.2.2.1 Mucus and Exopolymer Secretions 30
2.2.2.2 Detritus and Bacteria ..... . 31
2.2.3 Plants ............... . 35
2.2.4 Animals (Meio- and Macrofauna) 37
2.2.5 Animal Biogenic Structure (Tubes) 39
2.2.6 Conclusions . . . . . . . . . . . . . 40
3 Meiofauna Sampling and Processing 44
3.1 Sampling ............. . 44
3.1.1 Number of Replicates, Sample Size 44
3:1.2 Sampling Devices . . . . . . . . . . 46
XII Contents
3.1.2.1 Qualitative Sampling . . . . 46
3.1.2.2 Quantitative Sampling . . . 47
3.2 Processing of Meiofauna Samples 54
3.2.1 Extraction of Meiofauna 54
3.2.1.1 Sample Staining 54
3.2.1.2 Qualitative Extraction 55
3.2.1.3 Quantitative Extraction 55
3.2.2 Fixation and Preservation 57
3.2.3 Selected Instruments for Processing of Meiofauna
Organisms ........ . 59
3.3 Extraction of Pore Water 61
3.3.1 Suction Sampling . . 61
3.3.2 Squeeze Sampling 63
3.3.3 Centrifuge Sampling 63
4 Biological Characteristics of Meiofauna 64
4.1 Adaptations to the Biotope .......... . 64
4.1.1 Adaptations to Narrow Spaces: Miniaturization,
Elongation, Flexibility ............. . 64
4.1.2 Adaptations to the Mobile Environment: Adhesion,
Modes of Locomotion, Reinforcing Structures ... 68
4.1.3 Adaptations Related to the Three-Dimensional, Dark
Environment: Static Organs, Reduction of Pigment
and Eyes ................. . 74
4.1.4 Adaptations Related to Reproduction and
Development ............... . 75
5 Meiofauna Taxa - a Systematic Account 78
5.1 Protista .................... . 78
5.1.1 Foraminifera (Sarcomastigophora, Rhizopoda) 78
5.1.2 Testacea (Rhizopoda) 80
5.1.3 Ciliophora . . . . . . 81
5.2 Cnidaria ...... . 85
5.2.1 Hydroida (Medusae) 86
5.2.2 Hydroida (Polyps) 88
5.2.3 Scyphozoa ..... . 88
5.2.4 Anthozoa ..... . 88
5.3 Free-Living Plathelminthes: Turbellarians 89
5.3.1 Acoela .............. . 91
5.3.2 Macrostomida . . . . . . . . . . . 91
5.3.3 Rhabdocoela ( = Neorhabdocoela) 91
5.3.4 Seriata ..... . 92
5.4 Gnathostomulida . . . . . . . . . 96
Contents XIII
5.5 Nemertinea ................... . 99
Group of Nemathelminthes (=Aschelminthes) 101
5.6 Nematoda .. 102
5.7 Gastrotricha . 110
5.8 Kinorhyncha 112
5.9 Priapulida . . 115
5.10 Loricifera .. 116
5.11 Rotifera. Rotatoria 118
5.12 Sipuncula . 121
5.13 Mollusca 121
5.13.1 Gastropoda . 123
5.13.2 Aplacophora 124
5.14 Annelida 124
5.14.1 Polychaeta 124
5.14.2 Oligochaeta 130
5.14.3 Annelida "incertae sedis" 134
5.15 Tardigrada ....... . 136
5.16 Crustacea ........ . 141
5.16.1 Cephalocarida (Anostraca) 142
5.16.2 Cladocera (Branchiopoda) 143
5.16.3 Ostracoda ....... . 144
5.16.4 Mystacocarida .... . 147
5.16.5 Copepoda: Harpacticoida 149
5.16.6 Copepoda: Cyclopoida 154
5.16.7 Malacostraca ..... . 155
5.16.7.1 Sync arid a ....... . 155
5.16.7.2 Thermosbaenacea. Pancarida 157
5.16.7.3 Peracarida ....... . 157
5.17 Acari ............ . 164
5.17.1 Halacaroidea: Halacaridae . . 164
5.17.2 Freshwater Mites: "Hydrachnellae". Stygothrombiidae
and Others ..... . 167
5.18 Palpigradi (Arachnida) .......... . 168
5.19 Pycnogonida ............... . 168
5.20 Terrigenous Arthoropoda (Thalassobionts) 169
5.21 Tentaculata . 170
5.21.1 Brachiopoda ..... . 170
5.21.2 Bryozoa ........ . 171
5.22 Kamptozoa. Entoprocta 172
5.23 Echinodermata ... 172
5.23.1 Holothuroidea 172
5.24 Tunicata (Chordata) 174
5.24.1 Ascidiacea . . . . . . 174
5.24.2 Sorberacea 175
5.25 Meiofauna Taxa - Concluding Remarks 176