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TitleDynamic aquaria: building and restoring living ecosystems
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xi

Preface

By the mid-20th century, widespread concerns were being
expressed for the way in which modern human popula-
tions and their industrial endeavors and products were
affecting both the environment in which they lived and
the planet’s wild populations and their ecosystems. Some
predictions for the future were dire, and enough environ-
mental activism developed so that some of the more
conspicuous problems (e.g. raw sewage, oil spills, DDT,
PCBs, chlorofluorocarbons, and atomic power radioac-
tive materials) were subsequently ameliorated or at least
subject to management (though never fully corrected).
However, the larger, more widespread, and chronic efflu-
ent problems of human society (e.g. nutrients, CO2, and
moderately toxic hydrocarbons) have continued to expand
their reach into every corner of the biosphere, atmosphere,
and hydrosphere. The ever-growing global human popu-
lation, the continuing process of habitat destruction, and
the ever-expanding desire of that population for a western
lifestyle, rich in fossil energy use and synthesized products,
using abundant raw materials, suggest that these prob-
lems, already built up over a century or more, and now
growing geometrically with population expansion, are not
going to be so easily ameliorated.

Atmospheric CO2 increase, with its concomitant
global warming, already seems beyond correction to a
large percentage of scientists, engineers, and educated
public. Yet, the degradation of our natural waters, and
especially our oceans, the latter being of considerably
greater mass than the atmosphere, is slower to be rec-
ognized; and orders of magnitude more difficult to cor-
rect. In many coastal waters, decades of environmental
effort backed by large financial expenditures have
failed to prevent a continuing and serious reduction in
water quality. Although, in many countries, regula-
tions to contain the widespread pollution of the atmos-
phere and natural waters have been initiated, habitat
destruction continues and increasing population and
advancing prosperity have overcome most efforts to
stem the tide of environmental degradation. As some
writers have so succinctly stated, we are slowly begin-
ning to stew in our own toxic brew.

We are hardly alone in expressing our grave concern
for the future of the human race if the full understand-
ing and correction of these issues does not become the

top priority of all human society. It seems highly
unlikely, no matter what our scientific and technical
prowess, that humans can survive on this planet, with
our few domesticated species, in the midst of a radi-
cally altered atmosphere and hydrosphere and a dys-
functional biosphere. It is most discomforting to hear
of new plans to purposefully inject pollutants into the
stratosphere, to act like a volcanic eruption, or to spray
iron dust on the oceans, hopefully to increase photo-
synthesis, and thereby, at least temporarily, reduce
global warming effects. Why is it that so much of our
educated humanity cannot conceive of working with
our biosphere, using processes that we know well, to
solve multiple environmental problems?

Ranging from the domestication of a few wild
species by chance beginning 10 000 years or more ago
to that by design in the last few centuries, human
efforts to extend utilization of our biosphere beyond
hunter-gathering have almost always been at the level
of an individual species. Limited polyculture, as farm
ponds, is practiced in some countries, and in the latter
half of the 20th century “permaculture,” following
some ancient practices on land, advocated polyculture;
however, by and large, our domesticates remain mono-
cultures. Compared to the global biodiversity (even the
already greatly reduced biodiversity of today), the
numbers of domesticated species remain vanishingly
small. The intensive management of farms and aqua-
cultures provides one of the most extensive elements
of coastal and oceanic pollution and wild ecosystem
loss. Unfortunately, especially in western cultures, it
remains deeply ingrained that only by optimizing all
aspects of single species culture, often at great environ-
mental cost, can we hope to support current human
populations. It also does not help that most economic
models call for ever-continuing growth, when this is
clearly the root of our failure to meet environmental
problems.

This book focuses on efforts to interact with and
effectively “domesticate” at the ecosystem level, to
build experimental ecosystems to learn, and to under-
take ecological engineering, as interaction with “wild”
ecosystems. Ultimately, we propose to optimize bio-
geochemical function and biodiversity, and to reform

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our relationship to our biosphere. As we explain in this
book, symbiosis has been a critical part of organic evolu-
tion. Likewise, humans have formed a number of sym-
bioses with plant and animal domesticates. Some very
influential and critical scientists have recognized that
the human symbioses collectively called farming have
been a mixed blessing for the human race. Nevertheless,
current human populations are demanding an ever-
expanding intensive global scale farming that typically
uses monocultures to optimize a single return; usually
this return is biomass for food, materials, and, more
recently, energy. However, the human race also requires
ecosystem/biosphere level atmospheric and hydros-
pheric cleaning, soil structuring services, and general
biogeochemical stabilization that our farming sym-
bioses do not and probably cannot provide. Global
warming is only one example of human overpowering
of those global ecosystem services. As we describe in
depth in this book, the experimental study of living
ecosystems can lead to “domesticated” ecosystems that
are far more efficient at solar energy capture than farm
monocultures, without providing the inevitable envi-
ronmental degradation of those monocultures. We
demonstrate that use of such systems can clean up much
of the damage already visited on our planet.

Significantly increased energy and materials conser-
vation is essential to current and future generations.
While this has been locally necessary in the past, as
many communities and even civilizations have found
out to their detriment, our great numbers and increasing
individual requirements have now expanded the con-
servation requirement to a global level. Unfortunately,
we are unlikely to achieve the level of conservation
needed to stop the global warming “steamroller,” and
ultimately coastal and oceanic depletion, unless we
expand the scale and depth of our photosynthetic sym-
bioses to both the landscape and the ecosystem level.
Some environmentalists will find the thought of domes-
ticating high-diversity, high-efficiency ecosystems as
undesirable, perhaps even encouraging human society
to neglect conservation and population reduction.
Indeed, this is a potential dilemma. However, even if a
broad spectrum of human society could be brought into
an extensive conservation mode, the inertia of global
population and degradation provides environmental
problems that are realistically beyond a simple conser-
vation solution.

In the earlier editions of this book, we presented a
methodology for re-creating functioning wild aquatic
ecosystems for research and education. The underlying
philosophy centered on the notion that many of those
ecosystems remained in the “wild state” and that it
was possible to re-create or model them experimen-
tally. Clearly, there is a broad gradient of ecosystem

degradation, and the waters of the Baltic Sea and
Chesapeake Bay are considerably more altered than
those around Tierra Del Fuego. However, as we shall
point out in our following text, numerous studies and
reports declare a global scale alteration of species
and community function that is likely to continue and
deepen. We have written this 3rd edition on the basic
premise that most aquatic ecosystems are no longer
“wild,” being subject to significant and negative
unplanned and uncontrolled human effects. We now
must treat wild ecosystems as controlled systems that
must be managed, and human effects ameliorated, just
as in our “captive” ecosystems. We have expanded our
earlier treatment of “Building Living Ecosystems” to
“Building and Restoring Living Ecosystems,” applying
much of the original methodology, where appropriate,
to “wild” systems management. We show that large-
scale ecosystem cleaning of human pollution, using
solar/algal techniques, can also provide considerable
usable energy to replace the fossil fuel use that is
responsible for much of the global environmental
degradation. Just as we have organized in the past to
industrialize, we must now re-organize to more fully
integrate with the Earth’s biosphere while switching to
renewable energy sources.

It has been 15 years since the 1st edition of Dynamic
Aquaria was completed; it has gone through several
printings, and the response, especially in the academic
and professional world, has been quite favorable.
Some of the model or controlled ecosystems described
in the 1st edition are still in operation. One system,
with its mechanical–electrical systems re-built, has
now been in operation for over 25 years. A few have
been extensively researched, and we can now report
in depth on their function. Those long-term systems
that have been carefully studied have shown complex
community and trophic structuring and extraordinary
biotic diversities based on reproductively maintained
populations.

The scientific context in which our approach to living
systems modeling has developed has changed signifi-
cantly. In the year Dynamic Aquaria was first published
(1991), the journal Ecological Engineering also appeared.
It has now completed its 15th year and has published
over 500 articles. Several scientific studies describing the
approaches of other scientists to living systems model-
ing have also appeared during the same time frame, and
more peripherally, but of considerable interest, the
Society and journal Restoration Ecology have matured.

In the public display/education arena, the
Smithsonian exhibit conveying the principles of
ecosystem operation to the public at large has now
moved to and become the “Smithsonian Marine
Ecosystems Exhibit” at Fort Pierce, Florida. However,

xii Preface

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Page 83

lifetime of the system, even though effectively it is con-
stantly “topped” by the greenhouse roof. In most cases,
when a woody plant reached the greenhouse roof, it was
pruned back.

Due to intense shading, the algal community in the
freshwater stream itself was limited; degrading higher
plant detritus was the primary energy source. The domi-
nant invertebrate grazers, for the small amount of algae
(i.e. periphyton) that was available, were the amphipod
Hyalella azteca and the snail Physella cubensis. The domi-
nant detrivore was the small shrimp Palaemonetes palido-
sus. The important carnivores in the freshwater system
were the centrarchid fish Lepomis punctatus and Lepomis
microlophus (bluegills) as well as the small but abundant
Hydra. The bluegills fed on the abundant Poecilia (mollies
and guppies), Lucania goodei (bluefin killi), and Gambusia
affinis (mosquito fish) that were successfully maintaining
populations in the system. The Hydra was perhaps feed-
ing on young fish, but more likely dominately on the
protozoan fauna. The crayfish Procambarus alleni was
numerous and reproductive when the system was young,
feeding on a surplus of detritus, its primary food source.
While it declined later, apparently due to predation by
centrarchid fish, it remained a part of the community and
continued to support a small reproductive population.

The primary physical structural elements of the
well-lighted upper pool, the equivalent of a sink hole
in the wild, were fiberglass walls and siliceous sand.
Thalia geniculata (arrowroot) was moderately abun-
dant, rooted in the siliceous sand, though it was heav-
ily coated with a calcareous periphyton. These habitats
supported abundant primary producers, primarily the
filamentous red alga Audouinella violacea, the matforming,

false-branching, blue-green Scytonema hofmanni, and
the floating aquatic fern Salvinia rotundifolia. The domi-
nant grazers on the algae were Poecilia latipinna and the
snail Melanoides tuberculata. Unlike the highly shaded
stream community, algal standing crop was high in this
unit, provided the primary internal energy source here,
and was undoubtedly an important input source to the
stream proper. The pH values were well above 8.0, as in
the wild, and considerable calcification occurred along
the water line of the tank above the Scytonema hofmanni
mat. Calcification also occurred on the higher plant
Thalia, where the blue-greens Calothrix crustacea and a
Tolypothrix species formed a whitish band similar to the
periphyton mat of many Everglades prairies. The snail
Melanoides tuberculata was particularly abundant in the
algal mat on the shallow sandy bottom section of the
pool. The dominant carnivores in the upper pool were
Fundulus chrysotus and Lucania goodei. These fish were
eating Hyalella azteca, Cypridopsis vidua, unidentified
midge larvae, and copepods while the herbivorous
mollies were consuming the algae and the rootlets of
the periodically abundant Salvinia.

On the microfaunal scale, while nearly 40 species
were tabulated, the amoeba Cochliopodium and ciliates
Vorticella microstoma and Platycola longicollis occurred
repeatedly and abundantly.

The entire species list tabulated in 1995, in comparison
to 1987 and 1992, is given in Tables 23.1–23.5. The domi-
nant species contrasted to the estuarine populations
were shown in Figures 22.10–22.13. Unfortunately, no
specialist was available to determine the insects in either
1992 or 1995. We refer the interested reader to the 1987
list in the first edition.

448 23. Freshwater Ecosystem Models

TABLE 23.4 Fish Present in the Florida Everglades Stream and Wetland Mesocosma

Status, 1995

Species 1987 1988 1989 1992 1995 No. adults Reproducing

Elassoma evergladei x x
Fundulus chrysotus x x x U 2 Yes
Gambusia affinis x x x R �20 Yes
Heterandria formosa x x x U �15 Yes
Ictalurus nebulosus x x x
Jordanella floridae x x
Labidesthes sicculus x x
Lepomis gulosus x x
Lepomis macrolophus x x x
Lepomis microlophus x x xnd R 2 Possibly
Lepomis punctatus R 3 Possibly
Lucania goodie x x x M �25 Yes
Poecilia latipinna x x x U �15 Yes
Poecilia reticulate x x xnd U �20 Yes

aAbundance codes: (R) rare, 1–4% of individuals within tank; (U) uncommon, 5–19% of individuals within tank; (M) moderate, 20–34% of
individuals within tank; (A) abundant, 35–100% of individuals within tank; (x) present; (xnd) present, not documented.

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Page 84

Mesocosm Success over 8 Years of Operation

The higher plant communities of this mesocosm,
except for a relatively few floating and benthic macro-
phytes, were largely located in the prairie and ham-
mock communities bordering the stream. These
communities generally maintained their integrity, with

most of the dominants of the wild analog remaining
dominant for over the 13 years that this system oper-
ated. More than 223 higher plant species were intro-
duced into this system as seedlings, saplings, or soil
seedbank elements. Fifty-four of those species were
ephemeral, never displayed good growth, and were only
seen for a short time in the first year. No attempts at
reintroduction of these species were made. Fourteen
species were lost as a direct result of insect pest infesta-
tions; only one of these was due to infestations of
“wild-type” insects (thrips on Ludwigia leptocarpa).

There were 21 species of trees or woody bushes in this
system, almost all of which are in the fully closed ham-
mock area. Many flowered and some produced seed, but
until an opening was created in the canopy, here, as well
as in the same situation in the wild (by storms or ageing),
the increase of populations through reproduction on the
time scale of the model was neither possible nor perti-
nent to the measure of success. A single woody indi-
vidual, a red mangrove, had invaded from the adjacent
estuary system and apparently established itself. A few
of the remaining trees did not do well, particularly the
oaks and the mahogany, and earlier we mentioned the
enveloping effect of a very large inland leather fern.
Here, the effect of an approximately 10-foot (over soil)
greenhouse roof is clearly more important than the
very limiting surface area for the hammocks.

Of the remaining roughly 40 species of herbaceous
plants, primarily in the prairie, most maintained their
populations quite well. Earlier, we mentioned the need
to install a greater soil slope and a higher elevation,
above water table than exists in the wild, if dry prairie
were to continue to be a viable community. This was a
design problem that needs to be corrected in future mod-
els. The primary problem with the prairie community,
however, was simply that because of its orientation it
received only northern light. The wild dominant, in these
environments, Cladium jamaicensis (sawgrass) forms par-
ticularly dense stands (and provided even more shad-
ing) in the mesocosm. Many more secondary and tertiary
species would almost certainly have survived in the
mesocosm prairie communities if it had been possible to
correct these structural and orientational problems.

In terms of available light, the stream community in
the freshwater system was more like a stream running
through a hammock in the wild. Only the upper pool, the
equivalent of a sink hole or old alligator hollow, in the
wild, served to match the open stream environment
characteristic of Everglades prairies. While few algae
with their typical calcifying effects occurred in the
hammock stream, the blue-green species Microcoleus
(Schizothrix) calcicola and Scytonema hofmanni were abun-
dant in the well-lighted upper pool. Both species
were involved in carbonate deposition in the highly

A Florida Everglades Stream and Wetland 449

TABLE 23.5 Aufwuchs Organisms Present in the Florida
Everglades Stream and Wetland Mesocosma

1989 1995

Diatoms
Cymbella sp. II
Cocconies spp II II

Navicula sp. IV II
Pleurosigma sp. II II
Synedra sp. II II
Tabellaria sp. II II
Amphora sp. II II
Fragilaria sp. II
Nitzschia sigmoidea II II
Gomphonema sp. II II
Rhopalodia sp. III I
Asterionella sp. II

Bacterial and particulate browsers
Flagellates

Anisonema sp. II
Peranema trichophora II I
Peranemopsis sp. II II

Amoebas
Arcella sp. II
Arcella vulgaris III II
Arcella dentate III I
Centropyxis sp. II
Cochliopodium sp. III
Dufflugia sp. III I

Grazing ciliates
Nassula sp. I III
Chilodonella sp. III II
Cinetnchilum magaritaceum II II
Paramecium bursaria II
Aspidisca costata II
Frontonia sp. I
Holosticha sp. II I

Filter-feeding ciliates
Vorticella microstoma III
Vorticella picta II
Vorticella convallaria II
Platycola longicollis III
Stentor mulleri I
Epistylis sp. II
Zoothamnium sp. II

Predators of protozoans (all ciliates)
Laxophyllum sp. I
Coleps hirtus II I
Litonotus sp. I
Heliophya sp. II II

aAbundance scale (on standard settling plates): I, single individual
seen; II, 2–10 individuals; III, 11–100 individuals. Data from D. Spoon;
from Adey et al. (1996).

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Page 165

Plate 58 500-foot ATS floway for tertiary sewage treatment at Patterson, California, as described in the text. The
surger unit can be seen at the uppermost end of the floway.

Plate 59 Early vacuum harvester on the Patterson tertiary treatment ATS. This unit was quite successful in its
function, but has generally been replaced by lighter, less costly units in later systems. Photo by Walter Adey.

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Page 166

Plate 60 HydroMentia S-154 ATS system north of Lake Okeechobee in South Florida. The performance of this system as a stand-alone for
removing nutrients, especially phosphorus, from drainage canals is described in detail in the text. Photo by Evan M. Skornick.

Plate 61 S-154 surger units at the upper end of the ATS floway,
with the feed water trough on the right. Newer units combine surg-
ers into a single large unit piped so that wave passage down the
entire floway can be simultaneous. Photo by Mark Zivojnovich.

Plate 62 Dense algal turf on the S-154 ATS floway just prior to har-
vest. The primary algal “framework” is a Cladophora species, though
numerous other species, including many filamentous and unicellular
diatoms, are also present. Photo by Chris Pacquin.

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