Beautiful, blessed floating Isles of Eldorado
Instead of creating more Frankenstein monsters and further imperiling our progeny, couldn’t we revive (and maybe refine) viable ancient methods to sustain ourselves? Nuclear energy, GMOs, plastics and lots of other innovations, inventions and developments since the advent of “civilization” don’t just involve unintended consequences, but seem to extend the addictive dependencies (including even grain and cheese) that started with agriculture. Only a very few of us can live as hunter-gatherers, but alternatives to our modern proclivities do exist.
If you ponder humanity’s prospects for the next 50 years, things look bleak. Climate change is shrinking our coastlines. Unsustainable farm practices are depleting our soil. Billions of new mouths will need to be fed. In a world of swelling populations and dwindling farmland, some predict we’re running out of places to go — and to grow food. What’s to be done?
A New York design firm has been growing plants on man-made islands near Manhattan and Philadelphia. On the western coast of Vancouver, 14 floating greenhouses and a two-story house are tethered together on re-purposed fish floats. In Thailand and the waterlogged Netherlands, movements are underway to construct floating homes, greenhouses, hospitals and prisons.
When Europeans began settling the Americas in the 15 and 1600s, they failed to recognize most local gardens, due to lack of mono-culture. Beans grew on corn stalks with melons beneath, and smelly Christians saw only jungle. Now our myopic, egotistic self-indulgence is leading to rising seas, expanding deserts and insufficient space. But “primitives” dealt well with space limitation. Remember, rain-forest had multiple levels with ecosystems above and below each other! Sky-scrapers are not the only way to gain new space.
Despite how it’s claimed that real estate is a good investment as they aren’t making any more of it, it appears that new agricultural spaces may be on the horizon. I don’t know that global warming will provide valuable new property at the earth’s poles, but what about those huge floating garbage-patches? Cover ‘em with hemp-fiber and grow mushrooms!
Lake Kisale, on the border of Congo and Zambia, is famous for floating islands inhabited by fishermen. John Geddie described them: “The matted growths of aquatic plants fringing its shores are cut off in sections, and towed to the center of the lake. Logs, brushwood, and earth are laid on the floating platform, until it acquires a consistency capable of supporting a native hut and a plot of bananas and other fruit trees, with a small flock of goats and poultry. The island is anchored by a stake driven into the bed of the lake, and if the fishing becomes scarce, or should other occasion occur for shifting the domicile, the proprietor simply draws the peg, and shifts the floating little mansion, farm and stick, whether he chooses.”
At Inle Lake in northern Burma there’s something similar. Around a quarter of the massive freshwater lake—the country’s second largest body of water—is topped with these manmade gardens. Farmers glide between their plots from atop boats often propelled by leg-powered oars. Produce (tomatoes, string beans, cucumbers, flowers, eggplants and gourds) is plucked from patches that rise and fall with the currents. Creating the tiny islands is no easy task. Farmers gather clumps of water hyacinth and sea-grass, secure them in place with large bamboo poles, which they then stake into the lake’s muddy bottom. They then heap even more layers of sea-grass and silt atop the mounds before planting seeds.
Traditional bamboo houses of Inle Lake are built on stilts with walls made by weaving strips of bamboo. This provide shade while the light structure and small wall-gaps allow passage to light and air. Since the house is raised on stilts, air can flow on all sides. Roof overhangs shade the walls and protect them from rain, and the structure dries quickly despite the humid environment.
Building atop a lake can provide additional benefits. When water evaporates, it cools down the air around it. Water has a high thermal capacity which means that water temperature varies less during the day than air temperature. It keeps houses and villages cooler during the day and warmer during the night, creating more stable temperatures than what can be achieved on land. On the lake there are fewer obstructions, so wind speeds are higher, providing even more cooling air flow.
Some newer houses are built with wood and have two stories. These houses look more durable and may have a higher status for some locals. But as the walls are more solid, less air passes through and this makes the houses less comfortable. The stilts of the houses rot and have to be replaced approximately every 15 years, and using a fast-growing material like bamboo makes replacing the stilts and the houses more sustainable.
While the houses don’t actually float, the gardens do and this makes them even more flood resistant. As the water level drops and rises, the man-made islands move with the water level. Growing food on the lake also increases the total land available for agriculture, and there is easy access to water for irrigation, even during the dry season.
The practice of farming atop the lake, rather than around it, is thought to have started in the 19th century before intensifying in the 1960s. Though the unusual agriculture has boosted the region’s economy, people have since started to worry that chemical fertilizers, pesticides, and runoff are destroying the lake’s natural ecosystem. Pesticide and fertilizer runoff from floating farms has led to many traditional fish species disappearing, and much less fishing.
When the Spanish arrived in 1519, they saw a vast network of “chinampas” (gardens protruding into or within lakes or ponds) in the shallow lake beds of the Mexico Valley, built from water hyacinth reeds topped with soil. The Aztec capital, Tenochtitlan, was surrounded withthese small artificial floating gardens for agriculture. These vast systems were self-watering, self-fertilizing, navigated easily by boats, and highly productive, demonstrating a perfect example of a multi-functioning, self-supporting, and life-regenerating system.
Other, more truly floating garden systems are found worldwide. In South East Asia they may have roots dating far before the Aztec Empire. Large scale floating gardens have been made with aquaponics systems in China, for growing rice, wheat and canna lily, with some installations exceeding 10,000 m2 (2.5 acres). Floating gardens are also found in Vietnam, Bangladesh, and more famously, in the famous floating gardens of Inle Lake in Myanmar. Floating artificial islands are generally made of bundled reeds, and the best known examples are those of the Uros people of Lake Titicaca, Peru, who build their villages upon what are in effect huge rafts of bundled totora reeds. The Uros originally created their islands to prevent attacks by their more aggressive neighbors, the Incas and Collas.
Spiral Island was a more modern one-person effort to build an artificial floating island, on the Caribbean coast of Mexico. Modern artificial islands mimicking the floating reed-beds of the Uros are increasingly used by local governments and catchment managers to improve water quality at source, reducing pollutants in surface water bodies and providing biodiversity habitat. Examples include Gold Coast City Council in Australia. Artificial floating reed-beds are commonly anchored to the shoreline or bottom of water body, to ensure the system does not float away in a storm event or create a hazard. A permaculture principle tells us to “Use edge and value the marginal.” The edges are where there’s the most biodiversity and productivity, as in an estuary, where the river meets the ocean, or at the edge of a forest and prairie. There can be canopy trees, understory trees and shrubs, land crops, edge crops, emergent crops, trellis crops, fish, crayfish, water fowl, chickens on the land base, and floating water plants for fertility and mulch production… There’s immense possibility in cultivating these systems: trellises hooping over the waterways with fruits hanging down which can be harvested by boat, or ways of easily draining the waterways to harvest fish/crayfish, and flooding the land base to bring nutrient rich water to the plants. There are extensive possibilities.
These islands can also act as floating treatment wetlands (FTW). Several plants can play a part of cleaning water by absorbing dissolved nutrients, such as excess nitrates and oxygen, thereby reducing the content of these chemicals. The FTW, based on the soil-less hydroponics technique, comprises four layers. Floatable bamboo forms its base over which styrofoam cubicles are placed. The third layer is composed of gunnybags. Gravel forms the final layer. Cleaning agents planted on the FTW are vetivers, canna, cattalis, bulrush, citronella, hibiscus, fountain grass, flowering herbs, tulsi and ashvagandha. The root systems filter out sediments and pollutants.
Floating islands are not all good. In the Brazilian Amazon, floating islands known as Matupá form naturally in lakes on the floodplains of white-water rivers, ranging in size from a few feet across (or a few square meters) to a few hectares and even hundreds of acres. Sometimes they're just drifting masses of peat, mud, and plants. In extreme cases, these “islands” contain trees over 50 feet tall and 8-12 inches in diameter. These occur in Argentina, Australia, Finland, India, Japan, Kenya, and Papua New Guinea. Aquatic plant managers call them tussocks, floating islands or floating forests. When freely drifting in Florida waterways, they can be extremely expensive in terms of property damage, lost income, and management costs. Tussocks and floating islands are a product of the natural aging process of water bodies and probably have always been a part of Florida’s shallow lakes. Historically, their occurrence was kept in check by periodic drought and fire that kept them within lake margins, or occasional floods that deposited them in uplands or downstream marshes. Nowadays, water levels in most of Florida’s public lakes are manipulated by weirs, dams, or levees, which eliminate extreme high and low water events that historically suppressed tussock and floating island formation.
If not managed, floating invasive plants like water hyacinth and water lettuce, can form large rafts that act as a substrate for emergent plants to colonize. Emergent plants like primrose willow tie the rafts together below the surface with their roots, and above the surface with stems and branches. Native emergent species such as pennywort and smartweed grow from the shoreline to form mats across the water surface. If the mats become large enough, wind and wave action can tear them loose, generating floating tussocks. The non-native Cuban bulrush (Oxycaryum cubense), a grass-like sedge, sends long runners among and over other emergent plants and can eventually displace them with a floating tussock of Cuban bulrush. As water levels increase after draw-downs or droughts, masses of spongy plants like cattail and pickerelweed can pull loose from shallow soft mud flats.
Floating islands can form in the same manner as tussocks. They’re comprised of aquatic and sometimes upland plants, and also herbaceous and woody plants. Most important, they’re characterized by suspended masses of organic deposits like peat and mud that vary from a few inches to a few feet thick. In some cases, the sediments are compact or fibrous enough that the emergent plants, whose roots are interwoven into the sediments, pull as much as several feet of organic material with them to the surface as lakes re-fill. Simply killing the vegetation on these floating islands doesn’t eliminate them. The mud, peat, and woody material continue to float and the cycle repeats; often they must be dismantled to be controlled.
Nutrient pollution is a growing problem along the Upper Mississippi, where water rich in nitrogen and phosphates from crop fertilizer flows directly into the river without the benefit of wetland filtration. The problem is particularly acute in the levee region of southern Iowa, where farmers are groping for a remedy. The polluted water eventually reaches the Gulf of Mexico, creating a dead zone that now spans 6,700 square miles and costs fisheries $2.8 billion per year.
Environmentalists have filed lawsuits against the Environmental Protection Agency to press for tighter standards for nitrogen and phosphorus runoff. Worried that the agency might step in with new mandates, farm groups are weighing a temporary solution: floating islands that could process the nutrients before they reach the river.
The islands are made from a nonwoven mat of filter material constructed from the recycled plastic bottles, with plant roots growing through the bottom of the mat, adding microbes that will eventually yield clean water and provide food for fish. They mimic the role that wetlands once played in assimilating sediment from local agriculture. Charles Theiling, a hydrological specialist for the Army Corps of Engineers in Davenport, Iowa. has met with 500 farmers who favor using a concentrated wetland-effect, or floating islands, for abating the runoff problem. The pollution is rooted in the disappearance of interconnected flood plains that once existed in this Upper Mississippi region, Mr. Theiling explained. “The flood plains acted like a kidney to the river — they filtered out the pollutants.” But where flood plains once existed, two million acres of rich agricultural land are now planted with corn in each growing season. Swamps have been drained and trees cut. Meanwhile, 110 individual levee districts with pumps and plumbing have been installed to limit flood risks on these lands, which means that excess rainfall is channeled directly into the levees. “Our river wetlands are degraded because of conditions of our watershed and the ones we created by eliminating the flood plain,” Theiling said. “We are not getting the natural ecosystem service benefits of nutrient processing and sediment assimilation that we would get if this land were in its natural state.”
Fertilizer doesn’t just promote growth in crops, but even for algae and microbes. Anything living will respond to fertilizer, most certainly aquatic plants and algae blooms that choke-off beneficial micro-organisms, limiting food sources for fish and other marine life. Floating Islands can support biological processes that feed on fertilizer in beneficial ways, cleaning the water, acting as a sort of bio-reactor, providing something for microscopic life forms to live on, drawing on the carbon in the water, while using up the phosphorous and nitrogen gas.
While the islands have not yet been used widely in the Upper Mississippi, over 4,800 have been installed around the world. Aside from the United States Army Corps of Engineers, public and private entities ranging from a wastewater facility at a Louisiana prison to a landfill in New Zealand have commissioned such islands to clean polluted water, provide nutrients for fish and contribute to species habitat.
Meanwhile, the natural world is rapidly becoming a giant pile of plastic waste. The ocean is full of plastic, with floating, continent-size patches of it in the Pacific and Atlantic Oceans, plus newly formed ones in the Arctic. Some uninhabited islands are drowning in the stuff. There are at least six huge garbage patches in our oceans; we’re slowly suffocating natural ecologies with our trash. Fish, birds, and other animals consume bits of the five trillion tons of plastic strewn about the ocean. Doing so can kill them. Weirdly, though, scientists have come to the conclusion that, based on the amount of plastic we make every year, there is only about one-hundredth as much of the plastic floating around as the numbers would suggest. Although there are many possible explanations for this, it may be that microbes are breaking the plastic down. A team of Japanese scientists found a species of bacteria that eats the type of plastic found in most disposable water bottles. The discovery could lead to new methods to manage the more than 50 million tons of this particular type of plastic produced globally each year.
Plastic for water bottles is known as polyethylene terephthalate, or PET. It’s found in polyester clothing, frozen-dinner trays and blister packaging; if you walk down the aisle in Wal-Mart you see lots of it. Part of the appeal of PET is that it is lightweight, colorless and strong. However, it’s also notoriously resistant to being broken down by microbes. Studies had found a few species of fungi which grow on PET, but until just recently, no microbes that can eat it.
In 2016, scientists from Japan tested different bacteria from a bottle recycling plant and found one they named Ideonella sakaiensis that could digest the plastic used to make single-use drinks bottles. In their testing, they inadvertently made an enzyme, PETase, even better at degrading PET. The resulting mutant PETase takes just a few days to break down PET, compared to the 450 years it takes for the stuff to degrade naturally. It works by secreting an enzyme, PETase, which splits certain chemical bonds (esters) in PET, leaving smaller molecules that the bacteria can absorb, using the carbon in them as a food source.
Although other bacterial enzymes were already known to slowly digest PET, the new enzyme had apparently evolved specifically for this job. This suggests it might be faster and more efficient and so have the potential for use in bio-recycling.
One internet article confusingly claims that there are plenty of cheaper and easier ways to break down and recycle PET. It claims that PET is in fact, one of the easier types of plastic to break down. So, industrial scale production of enzymes or genetically-modified bacteria isn’t necessary. But although bacteria that can eat oil have also been discovered, oil slicks also remain a huge problem, especially as the incidence of them isn’t decreasing either, no more than is the addition of methane and carbon dioxide to our atmosphere, despite that we know that this will make our climate over-like within this century.
PETase could be used to break down bottles before they end up in the environment, much as we could stop riding in cars and airplanes, but convenience continues to rule. “Current recycling strategies for PET bottles mostly focus on mechanical recycling, so they chop the bottles up and use them for applications that typically do not need the same materials requirements as bottles,” says study co-author Gregg Beckham, a researcher at the U.S. Department of Energy’s National Renewable Energy Laboratory. “Engineered enzymes that break PET down to its building blocks would enable the ability to do full bottle-to-bottle recycling,” which might help decrease oil drilling demands for new plastic production. Waxworm caterpillars have been found to break down plastic in a matter of hours, and mealworms possess gut microbes that eat through polystyrene. Beckham says, given how ubiquitous environmental pollution has become, “it is likely that microbes are evolving faster and better strategies to break down man-made plastics. It seems that nature is evolving solutions.” Seems kind of deus ex machina – we can’t help ourselves, so something else has to.
Although a growing number of plastic-consuming microbes will help limit the absolutely disgraceful amounts of plastic dumped, much is consumed by animals that get eaten by us. Our garbage hardly assists biodiversity, and only the morally repugnant think we can keep dumping plastic in the oceans without consequence, but most of our major decision-makers do appear to be morally repugnant.
Still, if these bacteria can be encouraged to proliferate across the ocean, it might reduce humanity’s negative impact on them. But some dismiss the idea of adding either the original bacteria or the genetically enhanced version to ocean environments to speed the degradation of plastic debris, calling it irresponsible, as there would be too many side effects for the ecosystem.
A machine to clean up the planet’s largest chunk of ocean plastic is scheduled to quite soon finally set sail. It’ll work on the Great Pacific Garbage Patch, halfway between California and Hawaii, collecting the 1.8 trillion pieces of plastic rubbish amassed there by ocean currents. The system uses a combination of huge floating nets (dubbed “screens”) held in place by giant tubes, ironically made out of plastic, to suck stubborn waste out of the water. It’ll transfer debris to large ships that will take it to shore for recycling. This intricate system is expected to start work by July, 2018. Ultimately, Ocean Cleanup (a Dutch non-profit behind the project) aims to install 60 giant floating scoops, each stretching a mile from end to end. Fish will be able to escape the screens by passing underneath them, while boats will collect the waste every six to eight weeks.
The ambitious system is the brainchild of Dutch teen prodigy Boyan Slat, who presented his ocean-cleaning machine at a Tedx talk six years ago. Despite skepticism from some scientists, Slat dropped out of college to pursue the venture, raising $2.2 million from a crowd-funding campaign, with millions more brought in by other investors.
The Great Pacific Garbage Patch (GPGP) spans 617,763 square miles; it’s larger than France, Germany and Spain combined and contains at least 79,000 tons of plastic. Most of it is “ghost gear”: parts of abandoned or lost fishing gear, including nets and ropes, often from illegal fishing boats. Ghost gear kills more than 100,000 whales, dolphins and seals each year, with many of the sea creatures drowned, strangled or mutilated by the plastic.
If instead of cleaning up that mess we’ve made, we try to utilize it as farmland, a new desalinization process, shock electrodialysis, would help. In it, water flows through a porous material made of tiny glass particles (called a frit), with membranes or electrodes sandwiching the porous material on each side. When an electric current flows through the system, the salty water divides into regions where the salt concentration is either depleted or enriched. When the current is increased to a certain point, it generates a shockwave between the two zones, sharply dividing the streams and allowing the fresh and salty regions to be separated by a simple physical barrier at the center of the flow. Water flows across the membranes, not through them, which means they’re not as vulnerable to fouling (buildup of filtered material) or to degradation due to water pressure, as in regular membrane-based desalination, including conventional electrodialysis, which has the potential to desalinate seawater quickly and cheaply - but doesn’t remove dirt and bacteria. Shock electrodialysis, however, removes both salt and particulate matter including bacteria.
Forward osmosis pulls water molecules across a membrane, leaving salt and impurities behind, using less than a quarter of the electricity needed for standard desalination, making it easier for the technology to run on renewable power.
Large parabolic mirrors can be used to collect and concentrate the sun’s energy. Inside this solar still, pure water evaporates, while solids remain behind. The system is currently being tested by a water district in California’s agricultural Central Valley, cleaning irrigation runoff tainted with salts leached from the soil.
Another new technology takes water from the air, but how the completely dry air left from this process affects the rest of the atmosphere, and weather patterns, is not understood.
Researchers in India have come up with a water purification system using nanotechnology to remove microbes, bacteria and other matter from water, by using composite nanoparticles, which emit silver ions that destroy contaminants. Graphene-oxide membranes have attracted considerable attention as promising candidates for new filtration technologies. Now the much sought-after development of making membranes capable of sieving common salts has been achieved. Possibly, graphene-oxide membrane systems can be built on smaller scales making this technology accessible to countries which do not have the financial infrastructure to fund large plants without compromising the yield of fresh water produced.
The Solvay process, a 150-year-old, seven-step chemical conversion method that is widely used to produce sodium carbonate for industrial applications, and that many chemists are working to refine, has been simplified by aiming for sodium bicarbonate (baking soda) rather than sodium carbonate, thus reducing the needed chemical conversion steps to just two. The presence of ammonia causes pure carbon dioxide to react with waste brine from desalination, and create a solid baking soda and ammonium chloride solution. The second step creates an ammonium chloride solution and calcium oxide reaction, producing calcium chloride solution and ammonia gas. Recovering the ammonia allows it to be reused in the first step, reducing the cost of the process.
Even were garbage patches to be surrounded by huge nylon nets bigger than nets used for industrial fishing, microscopic bits of plastic would still contaminate sea-life, much as happens with expensive bottled water so popular of recent. Well, hot-dogs, sausages and noodles are often coated in plastic, and many of us eat that, and sea-life is getting irradiated anyway. So maybe floating monoculture as would please Global AgraBiz is a possibility. Strides in wind and solar power, battery miniaturization and longevity, desalinization and perhaps other technologies might help. Should we be able to expand food production and even living space on the high seas, ocean death might not be seen as the huge problem it actually is, but this shouldn’t be. We can no more do without sea-life than without insects of large predators, regardless of how difficult it is to convince many of these truths. Dead oceans wouldn’t produce oxygen, but rather other gasses, and resultant climate change is difficult to even imagine. In a dead ocean, who knows where a floating island might end up? Currants and winds would be completely different.
Imagination is of the essence here. Either we find ways of combining ancient wisdom with modern discoveries, or society as we have come to know it completely disappears. In all likelihood, within two decades we’re going to be completely dependent on substances that, in their infinite wisdom, our businessmen and politicos have made illegal. For the sake of all, let’s hope we can make it that far without deus ex machina (count on God or the Tao helping only those who help themselves).
A few days after putting this together, it occurred to me that floating doesn't need to involve liquid - maybe polar methane freed up by our release of too much CO2 could be put in huge balloons to support flying islands! Maybe those who'd live on them wouldn't care how taking water from nearby air would affect the rest of the atmosphere...
If you ponder humanity’s prospects for the next 50 years, things look bleak. Climate change is shrinking our coastlines. Unsustainable farm practices are depleting our soil. Billions of new mouths will need to be fed. In a world of swelling populations and dwindling farmland, some predict we’re running out of places to go — and to grow food. What’s to be done?
A New York design firm has been growing plants on man-made islands near Manhattan and Philadelphia. On the western coast of Vancouver, 14 floating greenhouses and a two-story house are tethered together on re-purposed fish floats. In Thailand and the waterlogged Netherlands, movements are underway to construct floating homes, greenhouses, hospitals and prisons.
When Europeans began settling the Americas in the 15 and 1600s, they failed to recognize most local gardens, due to lack of mono-culture. Beans grew on corn stalks with melons beneath, and smelly Christians saw only jungle. Now our myopic, egotistic self-indulgence is leading to rising seas, expanding deserts and insufficient space. But “primitives” dealt well with space limitation. Remember, rain-forest had multiple levels with ecosystems above and below each other! Sky-scrapers are not the only way to gain new space.
Despite how it’s claimed that real estate is a good investment as they aren’t making any more of it, it appears that new agricultural spaces may be on the horizon. I don’t know that global warming will provide valuable new property at the earth’s poles, but what about those huge floating garbage-patches? Cover ‘em with hemp-fiber and grow mushrooms!
Lake Kisale, on the border of Congo and Zambia, is famous for floating islands inhabited by fishermen. John Geddie described them: “The matted growths of aquatic plants fringing its shores are cut off in sections, and towed to the center of the lake. Logs, brushwood, and earth are laid on the floating platform, until it acquires a consistency capable of supporting a native hut and a plot of bananas and other fruit trees, with a small flock of goats and poultry. The island is anchored by a stake driven into the bed of the lake, and if the fishing becomes scarce, or should other occasion occur for shifting the domicile, the proprietor simply draws the peg, and shifts the floating little mansion, farm and stick, whether he chooses.”
At Inle Lake in northern Burma there’s something similar. Around a quarter of the massive freshwater lake—the country’s second largest body of water—is topped with these manmade gardens. Farmers glide between their plots from atop boats often propelled by leg-powered oars. Produce (tomatoes, string beans, cucumbers, flowers, eggplants and gourds) is plucked from patches that rise and fall with the currents. Creating the tiny islands is no easy task. Farmers gather clumps of water hyacinth and sea-grass, secure them in place with large bamboo poles, which they then stake into the lake’s muddy bottom. They then heap even more layers of sea-grass and silt atop the mounds before planting seeds.
Traditional bamboo houses of Inle Lake are built on stilts with walls made by weaving strips of bamboo. This provide shade while the light structure and small wall-gaps allow passage to light and air. Since the house is raised on stilts, air can flow on all sides. Roof overhangs shade the walls and protect them from rain, and the structure dries quickly despite the humid environment.
Building atop a lake can provide additional benefits. When water evaporates, it cools down the air around it. Water has a high thermal capacity which means that water temperature varies less during the day than air temperature. It keeps houses and villages cooler during the day and warmer during the night, creating more stable temperatures than what can be achieved on land. On the lake there are fewer obstructions, so wind speeds are higher, providing even more cooling air flow.
Some newer houses are built with wood and have two stories. These houses look more durable and may have a higher status for some locals. But as the walls are more solid, less air passes through and this makes the houses less comfortable. The stilts of the houses rot and have to be replaced approximately every 15 years, and using a fast-growing material like bamboo makes replacing the stilts and the houses more sustainable.
While the houses don’t actually float, the gardens do and this makes them even more flood resistant. As the water level drops and rises, the man-made islands move with the water level. Growing food on the lake also increases the total land available for agriculture, and there is easy access to water for irrigation, even during the dry season.
The practice of farming atop the lake, rather than around it, is thought to have started in the 19th century before intensifying in the 1960s. Though the unusual agriculture has boosted the region’s economy, people have since started to worry that chemical fertilizers, pesticides, and runoff are destroying the lake’s natural ecosystem. Pesticide and fertilizer runoff from floating farms has led to many traditional fish species disappearing, and much less fishing.
When the Spanish arrived in 1519, they saw a vast network of “chinampas” (gardens protruding into or within lakes or ponds) in the shallow lake beds of the Mexico Valley, built from water hyacinth reeds topped with soil. The Aztec capital, Tenochtitlan, was surrounded withthese small artificial floating gardens for agriculture. These vast systems were self-watering, self-fertilizing, navigated easily by boats, and highly productive, demonstrating a perfect example of a multi-functioning, self-supporting, and life-regenerating system.
Other, more truly floating garden systems are found worldwide. In South East Asia they may have roots dating far before the Aztec Empire. Large scale floating gardens have been made with aquaponics systems in China, for growing rice, wheat and canna lily, with some installations exceeding 10,000 m2 (2.5 acres). Floating gardens are also found in Vietnam, Bangladesh, and more famously, in the famous floating gardens of Inle Lake in Myanmar. Floating artificial islands are generally made of bundled reeds, and the best known examples are those of the Uros people of Lake Titicaca, Peru, who build their villages upon what are in effect huge rafts of bundled totora reeds. The Uros originally created their islands to prevent attacks by their more aggressive neighbors, the Incas and Collas.
Spiral Island was a more modern one-person effort to build an artificial floating island, on the Caribbean coast of Mexico. Modern artificial islands mimicking the floating reed-beds of the Uros are increasingly used by local governments and catchment managers to improve water quality at source, reducing pollutants in surface water bodies and providing biodiversity habitat. Examples include Gold Coast City Council in Australia. Artificial floating reed-beds are commonly anchored to the shoreline or bottom of water body, to ensure the system does not float away in a storm event or create a hazard. A permaculture principle tells us to “Use edge and value the marginal.” The edges are where there’s the most biodiversity and productivity, as in an estuary, where the river meets the ocean, or at the edge of a forest and prairie. There can be canopy trees, understory trees and shrubs, land crops, edge crops, emergent crops, trellis crops, fish, crayfish, water fowl, chickens on the land base, and floating water plants for fertility and mulch production… There’s immense possibility in cultivating these systems: trellises hooping over the waterways with fruits hanging down which can be harvested by boat, or ways of easily draining the waterways to harvest fish/crayfish, and flooding the land base to bring nutrient rich water to the plants. There are extensive possibilities.
These islands can also act as floating treatment wetlands (FTW). Several plants can play a part of cleaning water by absorbing dissolved nutrients, such as excess nitrates and oxygen, thereby reducing the content of these chemicals. The FTW, based on the soil-less hydroponics technique, comprises four layers. Floatable bamboo forms its base over which styrofoam cubicles are placed. The third layer is composed of gunnybags. Gravel forms the final layer. Cleaning agents planted on the FTW are vetivers, canna, cattalis, bulrush, citronella, hibiscus, fountain grass, flowering herbs, tulsi and ashvagandha. The root systems filter out sediments and pollutants.
Floating islands are not all good. In the Brazilian Amazon, floating islands known as Matupá form naturally in lakes on the floodplains of white-water rivers, ranging in size from a few feet across (or a few square meters) to a few hectares and even hundreds of acres. Sometimes they're just drifting masses of peat, mud, and plants. In extreme cases, these “islands” contain trees over 50 feet tall and 8-12 inches in diameter. These occur in Argentina, Australia, Finland, India, Japan, Kenya, and Papua New Guinea. Aquatic plant managers call them tussocks, floating islands or floating forests. When freely drifting in Florida waterways, they can be extremely expensive in terms of property damage, lost income, and management costs. Tussocks and floating islands are a product of the natural aging process of water bodies and probably have always been a part of Florida’s shallow lakes. Historically, their occurrence was kept in check by periodic drought and fire that kept them within lake margins, or occasional floods that deposited them in uplands or downstream marshes. Nowadays, water levels in most of Florida’s public lakes are manipulated by weirs, dams, or levees, which eliminate extreme high and low water events that historically suppressed tussock and floating island formation.
If not managed, floating invasive plants like water hyacinth and water lettuce, can form large rafts that act as a substrate for emergent plants to colonize. Emergent plants like primrose willow tie the rafts together below the surface with their roots, and above the surface with stems and branches. Native emergent species such as pennywort and smartweed grow from the shoreline to form mats across the water surface. If the mats become large enough, wind and wave action can tear them loose, generating floating tussocks. The non-native Cuban bulrush (Oxycaryum cubense), a grass-like sedge, sends long runners among and over other emergent plants and can eventually displace them with a floating tussock of Cuban bulrush. As water levels increase after draw-downs or droughts, masses of spongy plants like cattail and pickerelweed can pull loose from shallow soft mud flats.
Floating islands can form in the same manner as tussocks. They’re comprised of aquatic and sometimes upland plants, and also herbaceous and woody plants. Most important, they’re characterized by suspended masses of organic deposits like peat and mud that vary from a few inches to a few feet thick. In some cases, the sediments are compact or fibrous enough that the emergent plants, whose roots are interwoven into the sediments, pull as much as several feet of organic material with them to the surface as lakes re-fill. Simply killing the vegetation on these floating islands doesn’t eliminate them. The mud, peat, and woody material continue to float and the cycle repeats; often they must be dismantled to be controlled.
Nutrient pollution is a growing problem along the Upper Mississippi, where water rich in nitrogen and phosphates from crop fertilizer flows directly into the river without the benefit of wetland filtration. The problem is particularly acute in the levee region of southern Iowa, where farmers are groping for a remedy. The polluted water eventually reaches the Gulf of Mexico, creating a dead zone that now spans 6,700 square miles and costs fisheries $2.8 billion per year.
Environmentalists have filed lawsuits against the Environmental Protection Agency to press for tighter standards for nitrogen and phosphorus runoff. Worried that the agency might step in with new mandates, farm groups are weighing a temporary solution: floating islands that could process the nutrients before they reach the river.
The islands are made from a nonwoven mat of filter material constructed from the recycled plastic bottles, with plant roots growing through the bottom of the mat, adding microbes that will eventually yield clean water and provide food for fish. They mimic the role that wetlands once played in assimilating sediment from local agriculture. Charles Theiling, a hydrological specialist for the Army Corps of Engineers in Davenport, Iowa. has met with 500 farmers who favor using a concentrated wetland-effect, or floating islands, for abating the runoff problem. The pollution is rooted in the disappearance of interconnected flood plains that once existed in this Upper Mississippi region, Mr. Theiling explained. “The flood plains acted like a kidney to the river — they filtered out the pollutants.” But where flood plains once existed, two million acres of rich agricultural land are now planted with corn in each growing season. Swamps have been drained and trees cut. Meanwhile, 110 individual levee districts with pumps and plumbing have been installed to limit flood risks on these lands, which means that excess rainfall is channeled directly into the levees. “Our river wetlands are degraded because of conditions of our watershed and the ones we created by eliminating the flood plain,” Theiling said. “We are not getting the natural ecosystem service benefits of nutrient processing and sediment assimilation that we would get if this land were in its natural state.”
Fertilizer doesn’t just promote growth in crops, but even for algae and microbes. Anything living will respond to fertilizer, most certainly aquatic plants and algae blooms that choke-off beneficial micro-organisms, limiting food sources for fish and other marine life. Floating Islands can support biological processes that feed on fertilizer in beneficial ways, cleaning the water, acting as a sort of bio-reactor, providing something for microscopic life forms to live on, drawing on the carbon in the water, while using up the phosphorous and nitrogen gas.
While the islands have not yet been used widely in the Upper Mississippi, over 4,800 have been installed around the world. Aside from the United States Army Corps of Engineers, public and private entities ranging from a wastewater facility at a Louisiana prison to a landfill in New Zealand have commissioned such islands to clean polluted water, provide nutrients for fish and contribute to species habitat.
Meanwhile, the natural world is rapidly becoming a giant pile of plastic waste. The ocean is full of plastic, with floating, continent-size patches of it in the Pacific and Atlantic Oceans, plus newly formed ones in the Arctic. Some uninhabited islands are drowning in the stuff. There are at least six huge garbage patches in our oceans; we’re slowly suffocating natural ecologies with our trash. Fish, birds, and other animals consume bits of the five trillion tons of plastic strewn about the ocean. Doing so can kill them. Weirdly, though, scientists have come to the conclusion that, based on the amount of plastic we make every year, there is only about one-hundredth as much of the plastic floating around as the numbers would suggest. Although there are many possible explanations for this, it may be that microbes are breaking the plastic down. A team of Japanese scientists found a species of bacteria that eats the type of plastic found in most disposable water bottles. The discovery could lead to new methods to manage the more than 50 million tons of this particular type of plastic produced globally each year.
Plastic for water bottles is known as polyethylene terephthalate, or PET. It’s found in polyester clothing, frozen-dinner trays and blister packaging; if you walk down the aisle in Wal-Mart you see lots of it. Part of the appeal of PET is that it is lightweight, colorless and strong. However, it’s also notoriously resistant to being broken down by microbes. Studies had found a few species of fungi which grow on PET, but until just recently, no microbes that can eat it.
In 2016, scientists from Japan tested different bacteria from a bottle recycling plant and found one they named Ideonella sakaiensis that could digest the plastic used to make single-use drinks bottles. In their testing, they inadvertently made an enzyme, PETase, even better at degrading PET. The resulting mutant PETase takes just a few days to break down PET, compared to the 450 years it takes for the stuff to degrade naturally. It works by secreting an enzyme, PETase, which splits certain chemical bonds (esters) in PET, leaving smaller molecules that the bacteria can absorb, using the carbon in them as a food source.
Although other bacterial enzymes were already known to slowly digest PET, the new enzyme had apparently evolved specifically for this job. This suggests it might be faster and more efficient and so have the potential for use in bio-recycling.
One internet article confusingly claims that there are plenty of cheaper and easier ways to break down and recycle PET. It claims that PET is in fact, one of the easier types of plastic to break down. So, industrial scale production of enzymes or genetically-modified bacteria isn’t necessary. But although bacteria that can eat oil have also been discovered, oil slicks also remain a huge problem, especially as the incidence of them isn’t decreasing either, no more than is the addition of methane and carbon dioxide to our atmosphere, despite that we know that this will make our climate over-like within this century.
PETase could be used to break down bottles before they end up in the environment, much as we could stop riding in cars and airplanes, but convenience continues to rule. “Current recycling strategies for PET bottles mostly focus on mechanical recycling, so they chop the bottles up and use them for applications that typically do not need the same materials requirements as bottles,” says study co-author Gregg Beckham, a researcher at the U.S. Department of Energy’s National Renewable Energy Laboratory. “Engineered enzymes that break PET down to its building blocks would enable the ability to do full bottle-to-bottle recycling,” which might help decrease oil drilling demands for new plastic production. Waxworm caterpillars have been found to break down plastic in a matter of hours, and mealworms possess gut microbes that eat through polystyrene. Beckham says, given how ubiquitous environmental pollution has become, “it is likely that microbes are evolving faster and better strategies to break down man-made plastics. It seems that nature is evolving solutions.” Seems kind of deus ex machina – we can’t help ourselves, so something else has to.
Although a growing number of plastic-consuming microbes will help limit the absolutely disgraceful amounts of plastic dumped, much is consumed by animals that get eaten by us. Our garbage hardly assists biodiversity, and only the morally repugnant think we can keep dumping plastic in the oceans without consequence, but most of our major decision-makers do appear to be morally repugnant.
Still, if these bacteria can be encouraged to proliferate across the ocean, it might reduce humanity’s negative impact on them. But some dismiss the idea of adding either the original bacteria or the genetically enhanced version to ocean environments to speed the degradation of plastic debris, calling it irresponsible, as there would be too many side effects for the ecosystem.
A machine to clean up the planet’s largest chunk of ocean plastic is scheduled to quite soon finally set sail. It’ll work on the Great Pacific Garbage Patch, halfway between California and Hawaii, collecting the 1.8 trillion pieces of plastic rubbish amassed there by ocean currents. The system uses a combination of huge floating nets (dubbed “screens”) held in place by giant tubes, ironically made out of plastic, to suck stubborn waste out of the water. It’ll transfer debris to large ships that will take it to shore for recycling. This intricate system is expected to start work by July, 2018. Ultimately, Ocean Cleanup (a Dutch non-profit behind the project) aims to install 60 giant floating scoops, each stretching a mile from end to end. Fish will be able to escape the screens by passing underneath them, while boats will collect the waste every six to eight weeks.
The ambitious system is the brainchild of Dutch teen prodigy Boyan Slat, who presented his ocean-cleaning machine at a Tedx talk six years ago. Despite skepticism from some scientists, Slat dropped out of college to pursue the venture, raising $2.2 million from a crowd-funding campaign, with millions more brought in by other investors.
The Great Pacific Garbage Patch (GPGP) spans 617,763 square miles; it’s larger than France, Germany and Spain combined and contains at least 79,000 tons of plastic. Most of it is “ghost gear”: parts of abandoned or lost fishing gear, including nets and ropes, often from illegal fishing boats. Ghost gear kills more than 100,000 whales, dolphins and seals each year, with many of the sea creatures drowned, strangled or mutilated by the plastic.
If instead of cleaning up that mess we’ve made, we try to utilize it as farmland, a new desalinization process, shock electrodialysis, would help. In it, water flows through a porous material made of tiny glass particles (called a frit), with membranes or electrodes sandwiching the porous material on each side. When an electric current flows through the system, the salty water divides into regions where the salt concentration is either depleted or enriched. When the current is increased to a certain point, it generates a shockwave between the two zones, sharply dividing the streams and allowing the fresh and salty regions to be separated by a simple physical barrier at the center of the flow. Water flows across the membranes, not through them, which means they’re not as vulnerable to fouling (buildup of filtered material) or to degradation due to water pressure, as in regular membrane-based desalination, including conventional electrodialysis, which has the potential to desalinate seawater quickly and cheaply - but doesn’t remove dirt and bacteria. Shock electrodialysis, however, removes both salt and particulate matter including bacteria.
Forward osmosis pulls water molecules across a membrane, leaving salt and impurities behind, using less than a quarter of the electricity needed for standard desalination, making it easier for the technology to run on renewable power.
Large parabolic mirrors can be used to collect and concentrate the sun’s energy. Inside this solar still, pure water evaporates, while solids remain behind. The system is currently being tested by a water district in California’s agricultural Central Valley, cleaning irrigation runoff tainted with salts leached from the soil.
Another new technology takes water from the air, but how the completely dry air left from this process affects the rest of the atmosphere, and weather patterns, is not understood.
Researchers in India have come up with a water purification system using nanotechnology to remove microbes, bacteria and other matter from water, by using composite nanoparticles, which emit silver ions that destroy contaminants. Graphene-oxide membranes have attracted considerable attention as promising candidates for new filtration technologies. Now the much sought-after development of making membranes capable of sieving common salts has been achieved. Possibly, graphene-oxide membrane systems can be built on smaller scales making this technology accessible to countries which do not have the financial infrastructure to fund large plants without compromising the yield of fresh water produced.
The Solvay process, a 150-year-old, seven-step chemical conversion method that is widely used to produce sodium carbonate for industrial applications, and that many chemists are working to refine, has been simplified by aiming for sodium bicarbonate (baking soda) rather than sodium carbonate, thus reducing the needed chemical conversion steps to just two. The presence of ammonia causes pure carbon dioxide to react with waste brine from desalination, and create a solid baking soda and ammonium chloride solution. The second step creates an ammonium chloride solution and calcium oxide reaction, producing calcium chloride solution and ammonia gas. Recovering the ammonia allows it to be reused in the first step, reducing the cost of the process.
Even were garbage patches to be surrounded by huge nylon nets bigger than nets used for industrial fishing, microscopic bits of plastic would still contaminate sea-life, much as happens with expensive bottled water so popular of recent. Well, hot-dogs, sausages and noodles are often coated in plastic, and many of us eat that, and sea-life is getting irradiated anyway. So maybe floating monoculture as would please Global AgraBiz is a possibility. Strides in wind and solar power, battery miniaturization and longevity, desalinization and perhaps other technologies might help. Should we be able to expand food production and even living space on the high seas, ocean death might not be seen as the huge problem it actually is, but this shouldn’t be. We can no more do without sea-life than without insects of large predators, regardless of how difficult it is to convince many of these truths. Dead oceans wouldn’t produce oxygen, but rather other gasses, and resultant climate change is difficult to even imagine. In a dead ocean, who knows where a floating island might end up? Currants and winds would be completely different.
Imagination is of the essence here. Either we find ways of combining ancient wisdom with modern discoveries, or society as we have come to know it completely disappears. In all likelihood, within two decades we’re going to be completely dependent on substances that, in their infinite wisdom, our businessmen and politicos have made illegal. For the sake of all, let’s hope we can make it that far without deus ex machina (count on God or the Tao helping only those who help themselves).
A few days after putting this together, it occurred to me that floating doesn't need to involve liquid - maybe polar methane freed up by our release of too much CO2 could be put in huge balloons to support flying islands! Maybe those who'd live on them wouldn't care how taking water from nearby air would affect the rest of the atmosphere...
Labels: bacteria, chinampas, garbage patches, Inle, Kisale, ocean cleanup, permaculture, PET, plastic, pollution, shock electrodialysis, tussocks
posted by Mythorelics | 5:34 PM
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