MARINE BIOFOULING: COLONIZATION PROCESSES AND DEFENSES - CHAPTER 1 pptx

These are, in particular, locomotor reactions, taxes and drift of larvae, their sensoryand macroalgal spores, the impact of currents on colonization processes and spatialdistribution of

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MARINE BIOFOULING Colonization Processes

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Library of Congress Cataloging-in-Publication Data

Railkin, Alexander I.

Marine biofouling : colonization processes and defenses / by Alexander I Railkin ; translators, Tatiana A Ganf and Oleg G Manylov.

p cm.

Includes bibliographical references (p ).

ISBN 0-8493-1419-4 (alk paper)

1 Marine fouling organisms 2 Fouling I Title.

QH91.8.M3R35 2003 578.6'5'09162 dc22

2003055802

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Preface

to the American Edition

In the sea medium, the accumulation of organisms can be observed at the water–solidbody interface Biomasses developing on hard surfaces often exceed those on soft-ground bottom communities by tens and hundreds of times Such a concentration

of organisms points to their ecological and economic significance

Communities inhabiting hard substrates make a significant contribution to theproductivity and stability of coastal ecosystems They play an important role in self-purification of reservoirs, because they include organisms filtering great volumes ofwater when feeding and sedimenting suspended particles Settling on external andinternal surfaces of man-made structures, foulers hamper their exploitation, causingvast losses In a number of cases, they are sources of bioinvasion by harmfulorganisms, as was the case recently when zebra mussels colonized the Great Lakes

in the United States

Concentration of organisms occurs due to colonization processes that are erally similar on surfaces of underwater rocks, hard ground, coral reefs, macroalgae,invertebrate and vertebrate animals, ship hulls, and other objects Communitiesinhabiting hard substrates are similar in structure Their basis is created by attached

united into one ecological group in the book and are considered together

This book, published in Russia in 1998, was designed to explain the causes ofvast biomasses concentrating on submerged hard substrates The second task was

an attempt at a quantitative description of the colonization processes resulting insuch concentration The third task, associated with the first two, was analysis of thecommon causes of colonization of man-made structures and discussion ofapproaches to protection from biofouling, including ecologically safe methods.Solution of the above problems demanded a detailed consideration of the mainprocesses leading to colonization of various natural and artificial hard substrates:transport of dispersal forms (microorganisms, larvae, spores, etc.) by the current,and subsequent settlement, attachment, development, and growth This analysis made

it possible to explain the causes of concentration of micro- and macroorganisms onthe water–hard body interface In addition, the concept of processes necessary andsufficient for colonization of any hard surfaces was formulated, and mathematicalmodels of the main colonization processes were constructed On the basis of com-parative consideration of industrial antifouling measures and natural defense againstepibiosis the principles of ecologically safe protection of man-made structures frombiofouling and mathematical models of biofouling control were suggested.The wide range of problems presented in the book are rarely considered withinthe limits of one monograph and are not covered sufficiently in university courses

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These are, in particular, locomotor reactions, taxes and drift of larvae, their sensory

and macroalgal spores, the impact of currents on colonization processes and spatialdistribution of organisms on hard substrates, mechanisms of great biomass concen-tration on hard substrates, protection of macroalgae and animals from epibionts,industrial protection from biofouling, and problems of ecologically safe biofoulingcontrol The book presents a great number of Russian-language works which arenot widely known to non-Russian readers

Taking the above into consideration, the author hopes that this monograph will

be useful not only for biologists and engineers, state officials and experts who areinterested in and concerned with the problems of marine biology, aquaculture,protection from biofouling, and maintenance of environment, but also for studentsand postgraduates specializing in the problems of marine ecology, zoology, botany,and microbiology

Compared to the Russian edition, this monograph is thoroughly revised andsupplemented Considerable help in preparation of the U.S edition was afforded byA.S Elfimov, Ph.D (Russia), G.G Volsky, Ph.D (Russia), S Maack (Germany),N.V Usov (Russia), Prof S.A Karpov (Russia), and especially S.V Dobretsov,Ph.D (Russia), to whom the author expresses his sincere gratitude Owing to thehigh qualification and talent of the artist L Reznik (U.S.) and the computer graphicsspecialists A.O Domoratsky (Russia) and E.I Egorova (Russia), the book is wellillustrated

Alexander I Railkin

Saint-Petersburg

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Alexander I Railkin, Dr Sci., is Director of the

Research Institute of the Saint Petersburg StateUniversity (SPbSU) in Russia He graduated fromthis university in 1971 He was a post-graduatestudent (1971–1974), junior research worker(1974–1980), senior research worker (1980–1990),leading research worker (1990–1998), and, since

1998, has been Director of the Marine Laboratory(Marine Filial) at SPbSU He published 1 book andover 100 papers He has five Russian patents His current research interests are colonizationprocesses, larval behavior, role of hydrodynamicfactors in formation and development of benthic communities, and ecologically safeprotection from biofouling Simultaneously, Dr Railkin is an assistant professor atthe Faculty of Biology and Soils of SPbSU He gives master’s level lectures onmarine biofouling, experimental zoology, and ecology of protists

Dr Railkin is a member of the Russian Protozoological Society and the SaintPetersburg Society of Naturalists He is a member of two doctorate dissertationboards and the Research Board on Biodeterioration of the Russian Academy ofSciences

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Chapter 1

Communities on Submerged Hard Bodies 1

1.1 Organisms and Communities Inhabiting the Surfaces of Hard Bodies 1

1.2 The Phenomenon of Concentration of Organisms on the Surfaces of Hard Bodies 9

1.3 Biofouling as a Source of Technical Obstacles 14

Chapter 2 Biofouling as a Process 25

2.1 Colonization 25

2.2 Primary Succession 28

2.3 Recovery Successions Self-Assembly of Communities 35

Chapter 3 Temporary Planktonic Existence 41

3.1 Release of Propagules into Plankton 41

3.2 Buoyancy and Locomotion of Propagules 43

3.3 Taxes and Vertical Distribution of Larvae 48

3.4 Offshore and Oceanic Drift 52

Chapter 4 Settlement of Larvae 57

4.1 The Reasons for Passing to Periphytonic Existence 57

4.2 Taxes and Distribution of Larvae during Settlement 59

4.3 Sensory Systems Participating in Substrate Selection 63

4.4 Selectivity during Settlement 69

Chapter 5 Induction and Stimulation of Settlement by a Hard Surface 75

5.1 Types of Induction and Stimulation of Settlement 75

5.2 Distant Chemical Induction 77

5.3 Contact Heterospecific Chemical Induction 79

5.4 Conspecific Chemical Induction and Aggregations 81

5.5 Stimulation of Settlement, Attachment, and Metamorphosis by Microfouling 85

5.6 The Influence of Physical Surface Factors on Settlement 93

5.7 Combined Influence of Surface Factors on Settlement The Hierarchy of Factors 96

5.8 Settlement on the Surfaces of Technical Objects 100

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Chapter 6

Attachment, Development, and Growth 103

6.1 Attachment of Microorganisms 103

6.2 Mechanisms of Attachment of Larvae and Spores of Macroorganisms 112

6.3 Natural Inductors of Settlement, Attachment, and Metamorphosis 125

6.4 Universal Mechanisms of Attachment 129

6.5 Growth and Colonization of the Hard Surface 133

Chapter 7 Fundamentals of the Quantitative Theory of Colonization 143

7.1 Mathematical Models of Accumulation 143

7.2 Mathematical Models of Feeding and Growth 152

7.3 Gradient Distribution of Foulers over Surfaces in a Flow 156

Chapter 8 General Regularities of Biofouling 169

8.1 Causes, Mechanisms, and Limits of Biofouling Concentration on Hard Surfaces 169

8.2 Evolution of Hard-Substrate Communities 175

Chapter 9 Protection of Man-Made Structures against Biofouling 179

9.1 Physical Protection 179

9.2 Commercial Chemobiocidal Protection 182

9.3 Ecological Consequences of Toxicant Application 189

Chapter 10 Ecologically Safe Protection from Biofouling 195

10.1 Defense against Epibionts 195

10.2 Natural and Industrial Anticolonization Protection 204

10.3 Repellent Protection 207

10.4 Antiadhesive Protection 212

10.5 Biocidal Protection 215

10.6 Prospects of Developing Ecologically Safe Anticolonization Protection 221

Chapter 11 The General Model of Protection against Biofouling 227

Chapter 12 Conclusion 231

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References 235

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Submerged Hard Bodies

1.1 ORGANISMS AND COMMUNITIES INHABITING THE SURFACES OF HARD BODIES

In seas and oceans, especially along the coasts, there are many hard bodies, both atthe bottom and within the water column One group is made up of non-living naturalsubstrates: underwater rocks, reefs, hard ground, clastic rocks, stones, tree trunks,etc In another group, a more active one both chemically and physically, there areliving organisms: macroalgae and animals, whose surfaces are inhabited by numer-ous epibionts The third group includes material constructed of metal, plastic, con-crete, and wood: ships, pipelines, cables, piles, etc They may be chemically inert

or, on the contrary, aggressive, if they are protected from biofouling by toxic stances

sub-The underwater world of hard surfaces is rather diversified, both in its speciescomposition and in the abundance of organisms It includes various types of micro-organisms, invertebrates, and macroalgae It is rather heterogeneous because it isrepresented by communities developing on various hard substrates under differentecological conditions

V.N.N Marfenin (1993a) writes:

Among bottom biocenoses, the systems of hard grounds are the most variable ones They are populated both by seston feeders, utilizing suspended particles, zoo- and phytoplankton, and by algae (within the photic zone) Among them, numerous commensals, predators, and saprophages find shelter and food Animals from other biotopes frequently come to spawn there And all of this exists owing to the hard ground, which creates a reliable surface for colonization, and the water movement over the substrate, which brings food to the animals (p 131).

Coral reefs are well known hard-substrate communities (Odum, 1983; Naumov

et al., 1985; Sorokin, 1993; Valiela, 1995) The calcareous foundation of the reefmay go down many hundreds of meters, sometimes more than a kilometer It consists

of skeletons of dead organisms, mainly corals, sedentary reef-forming polychaetes,and coralline algae The total area of the live coral reefs in the Indian, Pacific, and

region of the Tropical zone is suitable for coral life Therefore, some experts believethat the corals could occupy an area 15 to 20 times greater (Naumov et al., 1985).Coral reefs are among the most productive areas in the world (Valiela, 1984, 1995)

On the hard substrates of the reef, the biomass of zoobenthos may exceed the biomass

of nearby soft grounds by one to three orders of magnitude (Sorokin, 1993) A vast

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2 Marine Biofouling: Colonization Processes and Defenses

number of animal and plant species inhabit the reef The population of a single reefusually includes over a hundred species of polychaetes, crustaceans, mollusks, andechinoderms

The plant and animal population of the benthos, plankton, and nekton may serve

as a hard substrate for communities of epibionts, which are extremely widespread(Wahl, 1989, 1997; Wahl and Mark, 1999) It is difficult to find species of attachedanimals and plants or slow moving animals which do not carry other organisms ontheir surface The specific features of communities developing on animals andmacroalgae are mainly determined by the way of life and other properties of thebasibiont organisms, serving as support for epibionts Many seaweeds are littlefouled or not fouled at all Of attached animals, only sponges are little fouled, andalso some corals and ascidians All those organisms release bioactive substances thatinhibit colonization and development of epibionts on them (see Chapter 10) Fast-swimming animals, such as fishes and dolphins, are also little fouled, which may

be partly accounted for by the toxins contained in their mucous covers (see Pawlik,1992)

Of practical importance are communities developing on the surfaces of industrialobjects: ships, port and hydrotechnical structures, pipes, fishing nets, and othermovable and stationary structures They are rather heterogeneous Some of them(nets, piles, moorings, etc.) have chemically inert surfaces and are subject to intensivecolonization by marine organisms Others, such as ships, are protected from fouling

by toxic substances As toxins in the paint are exhausted, the ship hull graduallygets fouled The communities of macroorganisms developing on such surfaces havelow diversity, owing to the dominance of the few macroalgal and invertebrate speciesmost resistant to the toxic paints and life on the surface of a moving ship

Different hard substrates, both natural and artificial, in accordance with theirintegral properties, can be divided into neutral, attractive, repellent, toxic, and bio-cidal The peculiarities of colonization of different types of surfaces by the dispersalforms are considered in Chapters 4 to 10

Communities developing on hard substrates on or near the bottom and in thewater column, in spite of certain differences in their structure and species compo-sition, are similar in general, because they develop in the same ecological environ-ment, on the interface between hard surfaces and water, usually under conditions ofincreased water exchange as compared to communities on soft ground The followinglife forms are characteristic of communities inhabiting hard substrates: sessile organ-isms, borers, and vagile forms (Railkin, 1998a)

In hard-substrate communities, sessile forms usually dominate in abundance andbiomass, and act as edificators, i.e., determine the community structure and itsmicroenvironment These include macroforms such as sponges, hydroids, corals,sessile polychaetes, barnacles, mussels, bryozoans, sea cucumbers, ascidians(Figure 1.1), and macroalgae (Figure 1.2) Microorganisms are mainly represented

by sessile bacteria, diatoms, microscopic fungi, heterotrophic flagellates, sarcodines,and sessile ciliates The sessile macroorganisms inhabiting hard surfaces, in turn,serve as a new substrate for colonization by other organisms, including sessile ones

As a result, new sessile organisms of the second, third, and higher orders are involved

in the process of successive colonization of the surfaces (Seravin et al., 1985), and

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FIGURE 1.1 Marine animals inhabiting surfaces of hard bodies (1) Sponge; (2) hydroid polyps; (3) coral sea pen; (4) polychaetes of the family Serpulidae; (5–6) cirripedes: acorn barnacles Balanus (5) and goose barnacles Lepas (6); (7) bryozoans; (8–11) mollusks: mussel

Mytilus (8), oyster Ostrea (9), abalone Haliotis (10), shipworm Teredo navalis and its tunnels in wood (11); (12–14) echinoderms: starfish Asterias rubens (12), sea urchin (13), sea cucumber (14); and (15) ascidian.

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thus these communities acquire a characteristic multilayered vertical structure taly, 1980; 2003)

(Par-Another life form typical of communities inhabiting hard substrates is composed

of the so-called borers, among which, together with sessile animals and macroalgae,vagile animals also occur Borers demonstrate high specialization and a close phys-iological and biological connection with the hard substrate (see Section 1.3) Thematerial they inhabit serves not only as shelter for them but also as a source of food.The paradox is that gradually eating the hard substrate (wood, stone, etc.), they mayfinally destroy it so thoroughly as to deprive themselves of the initial shelter.Besides the two specialized groups, hard substrates are also inhabited by suchvagile invertebrates as turbellarians, nematodes, errant polychaetes, crustaceans,gastropods, echinoderms (starfish and sea urchins), and also vagile microorganisms(mainly diatoms and various protists) The complicated branching, multilayeredstructure of the community formed by sessile macroorganisms reduces the hydro-dynamic action upon vagile forms and serves as a kind of protection for nonattachedspecies Macroalgae, settling on the hard surface, form a kind of canopy over it,which creates an additional substrate and also shelter for vagile organisms living onand under it Thus, among sessile organisms, vagile crustaceans, worms, mollusks,and also echinoderms find their abode It is also highly probable that vagile organismsinhabiting hard substrates, including hard grounds, may possess mechanisms ofincreased adhesion to the surface on which they move, since even at the bottom,they usually live under the condition of augmented hydrodynamic activity If theydid not possess such mechanisms, they would be easily washed away from thesurface

FIGURE 1.2 Marine macroalgae (1–2) Green algae Ulva (1) and Enteromorpha (2); (3) red alga Ahnfeltia; (4) brown alga Laminaria.

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Sessile, boring, and vagile forms inhabiting hard bodies are characterized bytheir position on the surface, fast adherence, and typically by being attached to thesurface In marine and fresh waters, the communities inhabiting hard substrates ofdifferent nature and origin are represented by similar life forms and may be consid-ered as a single ecological group (Railkin, 1998a) Within its limits, according tothe substrate criterion, smaller groups can be distinguished: communities of epib-enthos, inhabiting non-living substrates, such as submerged rocks, stones, hardground, etc (Savilov, 1961; Khailov et al., 1992; Oshurkov, 1993); communities ofepibionts inhabiting the surfaces of underwater animals and plants, sessile and vagile(Wahl, 1989, 1997); fouling communities on man-made structures (Costlow andTipper, 1984), and some others

Of course, not all communities possess all the characteristics described above.Any scheme, including the one above, is idealized to some extent Thus, the multi-layer structure of communities does not attain proper development Yet such majorcharacteristics as the dominance of sessile species, their edifying role in communi-ties, and finally their surface position on the substrate, are always present

Relegating of the hard-ground populations to the communities of hard substratesneeds further comments Let us seek them in the detailed study performed byA.I Savilov (1961) In the Sea of Okhotsk, he distinguished zones of prevalentdevelopment of different ecological groups Among them, the fauna of hard grounds(rocky, gravelly, sandy, and dense sandy-silt ones) is considerably developed in terms

of its abundance and biomass It is characterized by the prevalence of immotile sestonfeeders, represented by numerous species of sponges, hydroids, soft corals, gorgonar-ians, cirripedes, some bivalves, brachiopods, bryozoans, and ascidians, i.e., the samegroups (Figure 1.1) that inhabit hard substrates beyond the bottom Communities ofhard ground are subject to faster flows than those occurring on soft ground Similardescriptions of communities inhabiting hard ground are to be found in the works ofother authors (e.g., Osman, 1977; Sebens, 1985a, b; Protasov, 1994; Paine, 1994;Osman and Whitlatch, 1998)

In spite of a near 100-year history of studying hard substrates (Seligo, 1905;Zernov, 1914; Hentschel, 1916, 1921, 1923; Duplakoff, 1925; Karsinkin, 1925),there is still disagreement concerning the terms used to represent the communities

of microorganisms (Cook, 1956; Sládecˇková, 1962; Gorbenko, 1977; Weitzel, 1979;and others) and macroorganisms (Tarasov, 1961a, b; Konstantinov, 1979; Braiko,1985; Iserentant, 1987; Wahl, 1989, 1997; Railkin, 1998a; etc.) inhabiting them Forexample, a number of authors (Reznichenko et al., 1976; Braiko, 1985; Hüttinger,1988; Zvyagintsev and Ivin, 1992; Tkhung, 1994; Clare, 1996; Zvyagintsev, 1999,and others) consider that fouling communities represent a special assemblage oforganisms on artificial substrates and man-made structures rather than on naturalobjects Other authors (e.g., Mileikovsky, 1972; Zevina, 1994; Grishankov, 1995;Walters et al., 1996; Targett, 1997; Railkin, 1998a; Rittschof, 2000) regard fouling

as the process of colonization of any substrate, including natural (living and living) ones, and also as the result of this process — the communities formed onvarious hard substrates

non-A.A Protasov (1982, 1994) analyzed over 350 sources from the 1920s to theearly 1980s and found 21 terms for designating those communities Six of them

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appeared the most widely used: Aufwuchs (Seligo, 1915), Bewuchs (Hentschel,1916), periphyton (Behning, 1924), fouling (Visscher, 1928), and two Russian terms

obrastanie and perifiton, translated into English as fouling and periphyton, tively These terms were used in 89% of the cases and other terms were employed

respec-in 11%

In view of the common features of communities inhabiting hard substrates inthe aquatic medium, considered above, it is possible to unite them into one ecologicalgroup Following the historical tradition of assigning Greek names with the ending

term was first suggested by Behning (1924, 1929), though in a more narrow sense,

to designate fouling of objects introduced into water by man To designate

commu-nities Development of such communities will be referred to as biofouling or simplyfouling, and the organisms forming them as foulers

Unlike organisms inhabiting the surfaces of hard substrates, the typical itants of soft grounds are vagile or sedentary organisms that live mainly within theground and rarely on its surface It should be noted that the soft grounds includethe sediments (clay, silt, or fine sand) with particles below 1 mm in size Four lifeforms of the inhabitants of soft grounds can be distinguished (Zernov, 1949): (1)vagile forms inhabiting the surface, not infrequently partly submerged into theground (for example, echinoderms, crustaceans); (2) small vagile forms livingbetween ground particles; (3) large vagile burrowing forms; and (4) sedentary forms

inhab-It should be emphasized that sedentary or slow-moving invertebrates inhabitingthe soft bottom do not get attached to its particles but are only anchored in it or on

it Therefore they are not attached to the substrate as are the typical inhabitants ofhard substrates A stronger connection with the soft ground is achieved by differentmeans: due to the flattening of the body (e.g., many mollusks, starfishes, someurchins, encrusting bryozoans, calcareous algae), the thickening of the skeleton (anumber of polychaetes, brachiopods, mollusks, echinoderms, etc.), forming tubesout of ground particles (polychaetes) Sedentary organisms not infrequently developspecial rootlike outgrowths to hold themselves in sand and silt, which they do notpossess when they inhabit a hard surface This can be observed in a number ofsponges, soft corals, polychaetes, bryozoans, and ascidians (Savilov, 1961; Zen-kevich, 1977; Railkin and Dysina, 1997) In some cases such appendages may beconsiderably developed When typical inhabitants of hard grounds colonize softones, they usually first get attached to some hard substrate: fragments of shells,mollusks, shelters of other invertebrates, small stones, pebbles, etc (Savilov, 1961;Zenkevich, 1977) Usually these substrates are not to be seen from the surface ofthe soft ground since they gradually sink into the ground together with the organismsinhabiting them

Many invertebrates inhabiting soft ground live under conditions different fromthose characteristic of the hard substrates This can be accounted for by the fact thatmany species live within the ground Even species constantly existing on the surface

of the soft ground live, as a rule, under the condition of poor water exchange which

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occurs in the near-bottom layer Soft grounds are inhabited by organisms adapted

to life in narrow spaces and able to move within the ground They are oxygendeficient and have little if any light (Burkovsky, 1992; Valiela, 1995) Marine benthicgrounds are also characterized by a low pH and reduction-oxidation potential (eH)values Specific microorganism activity sometimes results in accumulation of a greatquantity of hydrogen sulfide, leading to the phenomenon known as “kill” The toxiceffect of sulfides is based on oxygen radicals (see Section 10.5) being formed fromreactions with sulfides (Tapley et al., 2003)

All the above allows us to distinguish the communities inhabiting soft ground as a

The same species of macro- and microorganisms may be members of nities inhabiting soft ground and hard substrates, including hard ground (e.g.,Savilov, 1961; Oshurkov, 1993) During reproduction periods, they releasepropagules into the plankton These propagules can settle on hard substrates andsoft ground and participate in the development of associations on them Thus, there

commu-is a regular exchange of dcommu-ispersal forms between the communities of hard and softsubstrates (Figure 1.3) Owing to this process, colonization of new and recruitment

of inhabited hard substrates is carried out, the species composition and size structure

of the community is maintained, and in case of disruption, their restoration is fast.Exchange is most intensive in the coastal areas, where especially high abundance

of organisms is observed on hard substrates and soft ground

As a result of the exchange of dispersal forms between epibenthic communitiesinhabiting hard ground and those formed on near-bottom hard substrates, both naturaland artificial, a convergent similarity may be observed in both species compositionand abundance Thus, V.V Oshurkov (1985, 1992) established a high similarity inspecies composition and abundance in the perennial fouling communities on asbestoscement and fiberglass in the water column with the closely located communitiesdeveloping on the stone bottom and on a sunken ship In all cases, the dominant

Similar communities may develop at the same stage of succession in the sameregion only in the presence of similar abiotic conditions, character and properties

of substrates If at least one of those conditions is not met, the species compositionand abundance of communities developing on different hard substrates in the samewater area may be rather different This has been noted repeatedly in the literature(Reznichenko et al., 1976; Zvyagintsev and Ivin, 1992; Zvyagintsev, 1999; Kashin

et al., 2000) G.B Zevina (1972) noted that “ship hull fouling differs from that ofpipelines or buoys but in principle these differences are neither greater nor less thanthose between the fouling of ship hulls, seines, and stones or rocks, i.e., betweenthe fouling of natural and artificial objects” (p 36)

In microorganisms (bacteria, unicellular algae, and protists), the dispersal formsare their vegetative (and sexual) cells, and also spores and cysts, which may becarried by water and air currents to long distances, resulting in their ubiquitousdistribution The dispersal forms of macroalgae are motile or immotile spores,whereas those of invertebrates and ascidians are motile larvae In their distribution,besides currents, an important role is played by their own motility and selectivity

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