ABSTRACT
Effective and sustainable habitat restoration requires innovative reef designs that optimize biological processes, alternative reef building methods that do not use plastic or concrete and that use renewable energy from solar, tidal, wind, and wave power as energy sources� Special attention must be paid to maximize the flow of water and light through the reef, providing reef inhabitants the maximum amount of oxygen, food, and nutrients while flushing away wastes� Reefs should be designed so that their shape increases the growth of structure builders such as coral and oysters, while providing habitat for other reef organisms to hide and spawn, increasing biodiversity�
This is especially important if the reef is to be used for sustainable fish and shellfish farming� Specially sized and shaped nooks and crannies can be designed into artificial reefs so that particular species will live there and can be successfully farmed without the use of nets, antibiotics, growth hormones, or external food addition� Special attention must also be paid to surrounding water and benthic habitat so there is as little impact as possible, and light as well as water can pass through the structure� Designs of structures presented in this chapter utilize the concept of “biomimicry�” Biomimicry, or innovation inspired by nature, adjusts its blueprints from Mother Nature’s designs which have evolved over billions of years, on a wide variety of scales from microscopic to megascopic
CONTENTS
Introduction: Principles of Sustainable Reef Design ��������������������������������������������������������������������� 245 Note on Materials���������������������������������������������������������������������������������������������������������������������������246 Oyster Restoration in New York City ��������������������������������������������������������������������������������������������246 Oyster Restoration Project at College Point, Queens, New York City ������������������������������������������250 Gill Reef ����������������������������������������������������������������������������������������������������������������������������������������� 253 Floating Reef ���������������������������������������������������������������������������������������������������������������������������������� 255 Solar-Powered Reef Buoys ������������������������������������������������������������������������������������������������������������� 257 Radiolarian Reef ���������������������������������������������������������������������������������������������������������������������������� 257 Coastline Management/Floating Island ����������������������������������������������������������������������������������������� 257 Amphibious Reef ��������������������������������������������������������������������������������������������������������������������������� 259 References �������������������������������������������������������������������������������������������������������������������������������������� 261
(Benyus, 1997)� Designs based on these principles should allow restoration of degraded habitat that is much more biologically diverse and productive than conventional artificial reef structures�
Please note that these structures are designed both with functionality and beauty in mind� The concept is that they could also be learning tools and be championed by their community to become sites for education and ecotourism, creating job opportunities for local people�
NOTE ON MATERIALS
There is no need to use plastic or concrete to make any of these structures� In places where the salinity is brackish or salty, my top recommendation would be to use Biorock in a mineral accretion process whereby low-voltage DC electricity is fed into metal� If grown slowly, Biorock is selfrepairing and three times the strength of concrete� Additional materials include high-fire ceramic coated with calcium carbonate and foamed glass mixed with calcium carbonate�
A recipe for oyster growth that can be used for coral as well is as follows� The most crucial ingredient, calcium carbonate, the substance shells are made from, is the basic
building block for oyster reefs� This recipe is designed for areas where reefs no longer exist, so alternative materials must be made to substitute for naturally occurring shells�
Note: This recipe does not use plastic or concrete� Examples are shown in Figures 18�1 through 18�8�
OYSTER RESTORATION IN NEW YORK CITY
Henry Hudson, the arctic explorer, sailed to Sandy Hook in 1609� Hudson’s crew found piles of oyster shell as high as homes of the time along the shores of Staten Island� These middens or piles of discarded oyster shells were the evidence that the Lenape, the American indigenous people, thrived on oysters� American oysters are difficult to farm� Instead of farming them, Hudson engaged in trade, exchanging tools for beans, corn, and oysters� This was the beginning of the North American oyster trade�
Oysters were the foundation of the commerce-driven New York, later called New Amsterdam� Hudson, an Englishman employed by the Dutch, ignited the first international oyster trade� It had its beginning with the Dutch New Netherlands Company (1614) that eventually became the Dutch West India Company� Rich and poor alike ate oysters� They were sold off in bundles of 600,000 to one customer at a time� Renowned for the best taste among oysters worldwide, New Amsterdam commerce thrived�
With 350 square miles of oyster reef, New York earned its title as the “Oyster Capital of the World” (Kurlansky, 2006)� Beginning with the American Industrial Revolution, the original oyster reefs disappeared from the Lower Hudson River Estuary (Waldman, 1999)� Oyster reefs declined due to overharvesting, pollution, disease, and rising water temperature� In addition to the demise of
the species, environmental factors have prevented its natural rehabilitation� Habitat-related stresses such as loss of substrate, decreases in salinity, changing currents, and a decrease in dissolved oxygen prevented oyster reef rejuvenation� Historian Mark Kurlansky, author of The Big Oyster: History on the Half Shell, states that perhaps “Ten million people produce far too much garbage” to be nurtured by one estuary� John Waldman, author of Heartbeats in the Muck, who also chronicled New York Harbor through the demise of the oyster, stated that the current health of New York Harbor is like “a healthy victim given chemotherapy and reconstructive surgery for problems she never had� Although the harbor’s native biological glory will never be relived, the prognosis is good for recuperation to a satisfactory functional level�”
OYSTER RESTORATION PROJECT AT COLLEGE POINT, QUEENS, NEW YORK CITY
The advantage of this structure is multifaceted� For one thing, the spiral of the helical shape takes up a minimal amount of space while providing a maximum amount of surface area for oysters to colonize� In addition, the shape has many open spaces for water to flow through, allowing for a maximum current bringing microparticles and plankton to the oysters and/or coral for nutrients or food� Because the structure contains a range of elevations spanning the height of the intertidal zone and has elements all with different orientations with regard to prevailing waves, it is ideal for experimental research on the importance of these crucial factors affecting food supplies, physical stress on growth rates, and settlement�
The vertical twisted forms are optimal for oyster beds because their vertical shape allows water to flow freely, thus allowing oysters to receive the maximum amount of nutrients and to capture the maximum amount of planktonic food, as well as keeping them above the sediment at the bottom� Vertical structures with plenty of ventilation have proven to be the best way to grow healthy oysters� This design is actually an improvement on the typical natural oyster bank, in which the oysters at the
bottom are often smothered in sediment or covered by other oysters at the top of the pile, so the ones on the bottom literally starve� To offset this problem, I created a design inspired by the double helix that allows water to flow freely in order for the oysters to receive the maximum amount of food and nutrients, while also efficiently flushing away their wastes� I utilized the architecture of preexisting wooden pilings as a structural support to create vertical structures (Figures 18�9 through 18�13)�
This is an environmentally sound and elegant use of old wooden pier pilings, which are found in vast numbers throughout the coastline of New York City’s waterways� They cannot be legally removed in New York City, because they are considered hazardous waste due to the toxic creosote coatings or copper and arsenic solutions impregnating them to prevent the action of marine boring organisms� The use of the pilings has the advantage of greater strength as well as saving space, while still enjoying the advantages of recreating a biodiverse habitat, and does not interfere with benthic (bottom-dwelling) fish�
GILL REEF
The design for this sculpture is based on the extremely efficient and elegant oyster gill (Figure 18�14)� One oyster in the height of the season can filter up to 50 gallons of water per day� I looked at the figures of microscopic oyster gills and then employed the concept of biomimcry, Mother Nature’s blueprints, to create the structure’s design� While working on the sculpture, I incorporated feedback from my students at the time-marine biologists, marine engineers, and the New York Department of Environmental Conservation�
Every aspect of the design strives to create the ultimate urban habitat for oysters (Figures 18�14 and 18�15)� The sculpture is engineered for 12-15 ft deep waters with underwater currents ranging between four and six knots� Oysters thrive in conditions where they receive the maximum amount of water flow, so the design is open and reticulated� This habitat is designed to be out of harm’s waysubmerged at the bottom of the river� The reef structure is lifted above the sediment, allowing every oyster access to nutritious currents� To further the likelihood of spat settlement, the reef structure is coated with lime-based substrate� An open channel in the middle and between each rib gives entry to divers who can monitor growth�
The gill can also operate as a land sculpture and teaching tool (Figures 18�16 and 18�17)�
FLOATING REEF
Fishermen know when they see a log floating in the water that there are fish schooling beneath it� This same principle was applied to the floating reef design; however, lightweight honeycomb structures have several advantages over a log� This floating reef design illustrates how reefs can be tethered to the ground, but can also be free-floating (Figures 18�18 through 18�22)� It is excellent for sustainable fish farming, because its lightweight honeycomb structure fans out allowing light to hit it; therefore, coral can grow on it� Also, it has many nooks and crannies for fish to congregate and hide in, and the structure allows water to flow through it, supplying food and removing wastes�
SOLAR-POWERED REEF BUOYS
The solar-powered reef buoy is a self-contained unit that acts not only as a navigational marker, but also is its own miniature floating reef (Figure 18�23)� If done properly, the solar panel could also generate hydrogen as well as power the reef’s structure below it� The solar-powered reef uses minerals dissolved in seawater to grow Biorock mineral accretion� Note: It is important to gauge over time how much buoyancy the solar buoy would require, because as mineral accretion and biological life-forms grow on it, the buoy would get heavier�
RADIOLARIAN REEF
This structure’s design is based on the siliceous skeleton of a radiolarian zooplankton (Figure 18�24)� This model depicts the plans for a reef structure that would act as a teaching tool about the importance of these microscopic structures, as well as become a home for coral and aquatic life that depends on healthy reefs� The circular shape is great for reef-making; Wolf Hilbertz often made dome shapes as his structures (Figure 18�25), because, if they were low enough, waves just washed over them, and they do not break and also offered protection for fish habitats, flow-through, and many surface areas for coral to grow�
COASTLINE MANAGEMENT/FLOATING ISLAND
This depiction is of a floating reticulated reef designed specifically for coastline protection as well as sustainable habitat (Figures 18�26 and 18�27)� As in the early drawing, the reef fits together like bones, so when a large wave comes, it absorbs the shock of the wave, protecting property and nature on its coasts� These reticulated reefs could be especially important now that sea-level rise is imminent� The later depiction is of a man-made island in which these floating reticulated reefs protect it� Note: As the mineral accretion grows on these structures, more buoyancy will have to be added�
AMPHIBIOUS REEF
“Enchanted Star Sand” is inspired by the unique shapes of sand found on Okinawa’s beaches (Figures 18�28 through 18�30)� “Star Sand” is formed by the shells of foraminiferans, which are single-celled calcareous marine organisms that live on the ocean floor� In this sculpture, these tiny star shapes cling to the delicate tentacles of a ctenophore or sea gooseberry� The ctenophore, also a planktonic marine organism, is perched on a cliff while its tentacles are submerged into the water, forming the reef below� This living sculpture would enhance the beauty of Miyako Island and protect its biodiversity, creating the perfect habitat for future aquatic and amphibious life� The concept for this project would be to create a living sculpture, which existed both below and above the intertidal zone� As transplanted coral develops on the structure, the reef will become a self-repairing breaker, protecting Miyako’s shorelines� Solutions for coastal protection are necessary in an age of sea-level rise due to climate change� Enchanted Star Sand would be created in an area on Miyako Island, where coastal erosion was already taking place or would be likely to take place in the future due to climate change and water-level rise� Enchanted Star Sand embodies the concept of geotherapy (Richard Grantham, 1992a, 1922b) or restorative action to heal the planet�
In conclusion, the underlying principle behind all of my reef work is geotherapy, which is based on the concept that the earth is now sick and needs to be healed through decisive human intervention� We must become caretakers for our ailing biosphere� I think of my reef work as a series of art actions to create both awareness and a physical manifestation of possible future solutions� Now more than ever, our cultural evolution affects our biological evolution (Van Rensselaer Potter, 1971)� We do not have time for the process of natural selection to occur, so we must rely on cultural adaptation to accelerate our evolution to acclimate to the threat of man-made climate change� It is my hope as an artist that combining innovative methods of sustainable reef restoration with aesthetics will inspire people to build not only a sustainable future but also a beautiful one�
REFERENCES
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