Chapter 3 Chapter 3 A City Without Us
One day nature will swallow everything, but it is difficult to apply this concept to something as large and concrete as a modern city.New York City is so huge, you can hardly imagine its gradual destruction. September 11, 2001 demonstrated that only a human with an explosive weapon has the power to destroy a city, not a natural process such as erosion or decay.The rapid collapse of the World Trade Center towers is horrifying. We pay more attention to the attackers of the towers than to the human frailty that can destroy the foundation of the entire human being.Even once such incredible disasters involved only a few buildings.But nature may be breaking free of urbanization much faster than we think.
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In 1939, New York hosted the World's Fair.To participate in the exhibition, the Polish government sent a statue of Wladyslaw II Jagiello.The establishment of a small reserve to protect the virgin forest six hundred years ago is not why the founder of the Białowieża forest became an immortal statue.Jagiello married the Queen of Poland, bringing his Grand Duchy of Lithuania into a union with Poland as a European power.The statue depicts him on horseback after his victory at the Battle of Grunwald in 1410.Triumphantly he holds up the two swords he had wrested from Poland's last enemy, the Germanic crusader knights.
In 1939, the Poles were not so lucky, because the descendants of those Germanic knights made a comeback.Before the World's Fair in New York ended, Nazi Hitler occupied Poland, and the statue could not be shipped back to its home country.Six tragic years later, the Polish government gifted it to New York as a symbol of indomitable victor.A statue of Jagiello was placed in Central Park overlooking what is known today as Turtle Pond.
Dr. Eric Sandersen and his party walk through Central Park, and they usually don't stop when they pass by the Jagiello statue, because they are all immersed in another century-the 17th century.Sanderson wears a wide-brimmed felt hat, glasses, and a gray beard trimmed neatly below his chin, and he tucks a laptop in his backpack.He's a landscape ecologist, and the others are from the Wildlife Conservation Society.This team of researchers from around the world is going to save the world from crisis.At the Bronx Zoo's headquarters, Sanderson oversees the Mannahata project.The project seeks to restore the island of Manhattan to what it was when Henry Hudson and his crew first discovered it in 1609: before the city was built, but tempting to imagine what the future might look like.
His team rummaged through original Dutch documents, colonial British military maps, topographic surveys and all the classified archives of the town over the centuries.They study sediments, analyze ancient pollen, and input tens of thousands of biological data into imaging software to generate a three-dimensional panorama of lush vegetation, and the image of the metropolis is also juxtaposed on it.With each input of a grass or tree that has historically grown somewhere in the city, the imagery becomes more specific and richer, surprising and convincing at the same time.What they're trying to create is a detailed map of a spooky forest that Eric Sanderson seems to be looking at all the time, even while dodging cars on Fifth Avenue.
As Sanderson strolls through Central Park, he gazes past the half a million cubic yards that designers Frederick Law Olmsted and Calvert Vaux have shipped here. looking at a soft swamp surrounded by poison ivy and sumac.He could walk along the shoreline of the long, narrow lake off Fifty-ninth Street north of what is now the Plaza Hotel, where the tidal waters meandered through the salt marshes into the East River.To the west, he saw two streams feeding into the lake, draining the slopes of Manhattan's Great Divide—once haunted by deer and mountain lions, now known as Broadway.
Eric Sandersen sees rivers all over the town, mostly from groundwater (“That’s how Spring 4th Street got its name”).He determined that a hilly, rocky island once flowed by more than forty creeks and rivers: it was first inhabited by the Delaware people, who, in their Algonquian language, " The word "Manhattan" refers to those small hills that are now gone.In the 19th century, the planners of New York City didn’t seem to take topographical factors into account at all, and designed all the places north of Greenwich Village to be vertical and horizontal (because the original streets in the south were so chaotic, it was impossible to plan them into square grid).Except for Central Park and the big, hulking schist formations on the island's northern tip, Manhattan's high ground is filled into the riverbed.People paved the ground and looked forward to a developed and advanced city.
Later the city took on a new outline.Water used to be the shaper of the terrain, but now it is forced into a network of underground pipes, so this time, straight lines and corners become the new outline features of the city.Erik Sanderson's plans for the Mannahata project show that modern sewer systems are nothing more than imitations of the waterways of the past, even though man-made sewers are not as efficient as nature.He commented on the city burying its own river: "The rain continues. The water has to go somewhere."
If nature starts tearing off Manhattan's hard shell, water is the problem.The problem will soon be exposed, with the brunt of the attacks taking place where the city's crust is weakest.
NYC Transit's Paul Schuber and Pete Briffa served as the Hydro Resources Supervisor and the Hydro Emergency Response Team's Level 1 Maintenance Supervisor, respectively.They are clear on the subject.Every day, they must keep 13 million gallons of water from flooding New York's subway system.
"It's just groundwater," Schuber said.
"Once it rains, the total amount of water..." Briffa spread his hands with a look of helplessness: "It cannot be counted."
Maybe not impossible to count, but it doesn't rain less now than it did when the city was first built.In the past, Manhattan's 27 square miles of permeable soil received an average annual rainfall of 47.2 inches, and the roots of trees and grass drank the water and then transpired the rest into the atmosphere.The water that the roots can't use will enter the island's groundwater system.In many places, the rainwater formed lakes and swamps, and the rest was drained into the ocean by forty rivers—now buried under concrete and asphalt.
Today, with little soil to absorb rainfall and little vegetation to transpire, since high-rise buildings block the sun, evaporation cannot take place, so rainwater either collects in puddles or is gravity-fed into sewers—or, into subways. There is already a lot of water accumulated in the ventilation holes.For example, below 131st Street and Lenox Avenue, the rising water level of the underground river has begun to corrode the bottom of the A, B, C, and D subway lines.Men like Schuber and Briffa in visor vests and overalls have been scrambling beneath the city, dealing with New York's rising water tables.
Every time a rainstorm comes, the sewers are clogged with garbage—the number of plastic bags in the cities of the world may really be countless—and the rainwater has to go somewhere, so it pours into the nearest subway corridor.In addition, to the northwest, waves from the Atlantic Ocean poured into New York's groundwater system, so that places like Manhattan's low-lying Water Street and the Yankee Stadium in the Bronx rose and flooded tunnels.Everything had to be shut down until the water level dropped back.If the oceans continue to warm and sea levels rise faster than the current rate of one inch per decade, then once a certain peak is reached, water levels will never fall back again.Schub and Briffa wondered what the city would look like by then.
Besides that, the waterway built in the 1930s is old and often bursts.In New York, the vigilance of subway crews and 753 sump pumps is the only guarantee that the city has not yet flooded.Consider those water pumps: New York's subway system was a marvelous project in 1903, built beneath an already existing, now highly developed city.Because the city already has drainage pipes, the only place to build a subway is under the pipes. "So," Schuber explained, "we have to pump the water up." New York isn't alone in doing this: Cities like London, Moscow, and Washington have much deeper subways, almost It can be used as an air-raid shelter.There are many potential dangers in these places.
Schuber's white hard hat shaded his eyes.He peers into a square-shaped pit beneath the Van Cikelen Avenue station in Brooklyn, where 650 gallons of natural groundwater gushes from a rock bed every minute.Pointing to the gushing water, he said that four cast-iron water pumps that can work underwater are pumping water up in turn.This water pump is powered by electricity.When the power goes out, things can go bad all of a sudden.After the attack on the World Trade Center, an emergency water pump truck was working with a huge portable diesel generator, pumping out 27 times the capacity of Hill Stadium.If the Hudson did flood and flooded the tracks connecting the New York subway to New Jersey (as it almost did once), the pump truck and much of the city would be submerged.
In an abandoned city, there will be no more Paul Schuber and Pete Briffa running from station to station every time there is more than two inches of rain (recent frequency It's annoyingly high), sometimes you have to run up and down the stairs with a hose to pump water into a sewer down the street, and sometimes you have to navigate a maze of tunnels in an inflatable boat.If there are no people, there is no electricity.The water pump is gone forever. "Once these pumps are turned off," Schub said, "within half an hour the water level will rise to the point where the subway can no longer go through."
Briffa took off his goggles and rubbed his eyes. "If there is a flood in one district, it will spread to other districts. In just thirty-six hours, the whole city will be flooded."
Even if it doesn't rain, they predict that if the subway pumps stop working, it will only take a few days to flood the entire city.By then, the water will have washed away the soil beneath the sidewalk.Before long, the streets will be potholed.No one will come to unclog the sewers, so some new waterways will form in the ground.After the roof of the flooded subway collapses, other rivers will emerge.Within twenty years, steel pipes immersed in water will corrode and deform.These steel pipes support the streets above the 4-5-6 line on the East Side.Lexington Avenue will become a river if it sinks.
Long before that, though, the city's sidewalks were in serious trouble.Dr. Jamil Armand, chair of the civil engineering department at New York's Cooper Institute, said that in the first three months after people move out of Manhattan, the city begins to fall apart.Every March, the temperature swings around 32 degrees Fahrenheit (zero Celsius) more than forty times (climate change may bring this up as early as February).By this time, the constant freezing and melting can crack the asphalt and cement.When the snow melts, water seeps into these new cracks.When freezing, water expands as it turns to ice, making the cracks bigger.
We could call this the revenge of the water, which has been suppressed by the city for too long.Almost all mixtures in nature shrink when they freeze, but water molecules do the opposite, forming elegant hexagonal crystals that take up nine percent more space than they would in their liquid state.The hexagonal ice flakes are so beautiful and flimsy that it's hard to imagine them damaging the concrete pavement that borders the sidewalk.It is even more inconceivable that a carbon steel water pipe, capable of withstanding a pressure of 7,500 pounds per square inch, could burst when it freezes.But this is the truth.
After the sidewalk cracks, weeds such as mustard, clover, goosegrass and other downwind grasses from Central Park grow down and penetrate the newly formed cracks, making them more cracked.In today's world, at the first sign of a problem, amenity teams show up to kill weeds and fill in cracks.But in a world without humans, no one would tinker with New York anymore.After the weeds came the most fertile exotic species in the city, the Asian Ailanthus tree.Even with a population of eight million, tenacious invaders such as Ailanthus trees (commonly known as Ailanthus trees) can take root in tiny cracks in tunnels, waiting for their unfurling branches to break through the sidewalk before people Pay attention.If no one comes to pull out their seedlings, within five years their mighty roots will be gripping sidewalks and wreaking havoc in the sewers—which are covered with plastic bags and rotting old Newspaper jam.As the soil long buried beneath sidewalks was suddenly exposed to sunlight and rain, the seeds of other trees took root in it, and it didn't take long for the leaves to join the growing army of trash clogging the sewers.
Plants don't have to wait until the day the sidewalk crumbles to take advantage of it.From the mulch that had accumulated in the gutters, a layer of soil formed over New York's barren crust, and seedlings began to sprout and shoot.They had much less access to organic matter, of course, just windblown dust and urban soot, but that is now the case for the abandoned elevated steel embankment of the New York Central Railroad west of Manhattan. Since 1980, this railway has been no longer used, and the pervasive Ailanthus tree has taken root here, as well as a thick layer of onion grass and furry cloverworms, dotted with autumn Unicorns.Remnants of old railroad tracks peek out from the two-story warehouse, and then escape into the elevated driveway lined with wild crocuses, irises, tuberoses, asters and wild carrots.Many New Yorkers looked down from the windows of the Chelsea Arts District and were moved by the natural, green ribbons of flowers that occupied a dead corner of the city and prophesied about the future.This place is the High Line Park in New York.
During the first few years without heat, the pipes were cracking all over the city, and the temperature fluctuations of freezing and thawing also affected the indoor homes, and things were badly damaged.The interior of the house creaked as it expanded and contracted; the hinges between the walls and the inner roof began to snap.Where it cracked, rain seeped in, the latches were rusted, and the veneer peeled off to reveal the sound-deadening cork layer.If cities are not on fire, now is the time.
In general, New York architecture is not as flammable as San Francisco's heavy Victorian siding.But with no firefighters to answer the fire calls anymore, a single bolt of lightning can ignite the many branches and leaves that have piled up in Central Park, and the flames will spread to the streets.Within two decades, lightning rods would start rusting and snapping, and fires on the roof would spread inside the building and into offices filled with paper fuel.Explosions from gas pipes shattered window panes.Rain and snow took the opportunity to get in, and before long, the concrete floor began to crack under the thermal expansion and contraction caused by freezing and melting.Layers of charred acoustic cork add nourishment to Manhattan's ever-expanding soil.Native Virginia reptiles and poison ivy crawl over walls covered in moss, which thrives in the absence of air pollution.Red-tailed hawks and peregrine falcons nest on high stilts.
Steven Clements, associate curator at the Brooklyn Botanic Garden, predicts that within two centuries, established trees will completely replace previous weeds.Beneath the tons of foliage are gutters that provide fresh, fertile soil for oaks and maples in local parks.Black acacias and autumn olives come here to fix nitrogen, as do sunflowers, bluestem, white snakeroot and apple trees, whose fruit is sown here and there by birds.
Jamil Armand, a professor of civil engineering at the Cooper College, predicts that biodiversity will be more pronounced because the lime in the cement raises the pH of the soil as tall buildings collapse and crumbles, such as laxatives. Trees not adapted to acidic conditions, such as buckthorn and birch, will take root here.Armand has gray hair, but he is full of energy, and he can't help gesticulating with his hands when he speaks. He thinks this process starts faster than people think.The scholar from Lahore, Pakistan, the city of mosaic-decorated mosques, is now teaching how to design and improve buildings to withstand terrorist attacks.He had a deep awareness of the structural weaknesses of buildings.
"Even if Manhattan's buildings are anchored in the hard schist, as most of New York's skyscrapers are," he commented, "that doesn't mean their foundations won't flood." Clogged sewers, flooded tunnels and already The avenues turned into rivers, he believes, under their combined action, the firmness of the foundations of buildings is weakened, and the behemoths they carry will become precarious.In the future, the hurricanes that hit the Atlantic coast of North America will become more violent and frequent, and the strong winds will blow mercilessly on those tall but unstable structures.Some will collapse and knock down other buildings.Just like when a big tree falls, new life will occupy that gap, and gradually, the steel forest in the city will become a real forest.
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Connected to the Bronx Zoo, the New York Botanical Garden covers 250 acres and has the largest wax leaf plant community outside Europe.It houses specimens of wildflowers collected during Captain Cook's voyage to the Pacific in 1769, and a smattering of mosses from Tierra del Fuego, accompanied by notes in black ink and signed by the collector - Charles Darwin.Most unusual, however, are the 40 acres of virgin forest that have never been logged in the New York Botanical Garden.
Although it has not been felled, it has undergone tremendous changes.Until recently, this graceful and whirling pine tree was called the hemlock forest.But nearly all of the hemlock is now dead, and the culprit is a Japanese insect smaller than the period at the end of this sentence that arrived in New York in the mid-1990s.The oldest and largest oaks date back to when the forest belonged to the British, but they too are dying.They are attacked by acid rain and heavy metals such as lead, as car exhaust and factory smog have been absorbed into the soil.There's no way they're coming back because most of the canopy trees have long since lost their ability to reproduce.All the trees that live here are now inhabited by pathogens: certain fungi, insects, or viruses that can kill trees if they get a chance -- trees that have become vulnerable to the onslaught of chemicals.And, as the forests of the New York Botanical Garden become green islands surrounded by gray cities, it also serves as a sanctuary for squirrels in the Bronx.There are no natural predators here, and hunting is forbidden, so there is nothing to prevent them from devouring the undeveloped acorns or hickory nuts.That's what they are.
Today, the understory of this ancient forest has a "generation gap" of eighty years.Instead of young oaks, maples, ash birches, fig trees, and tulips, here grows mainly exotic ornamental plants, brought here by the wind from other parts of the Bronx.Soil sampling studies have shown that 20 million Ailanthus seeds have taken root here.Chuck Peters, director of the Society for Economic Botany at the New York Botanical Garden, said exotic species — such as Ailanthus ailanthus and cork, both from China — now occupy a quarter of the forest.
"There are people who want to restore the forest to what it was 200 years ago," he said. "If that's the case, I have to tell them, it's like bringing the Bronx back to 200 years ago."
Since humans were able to move freely around the world, they took living things with them and brought back some other species.Plants from the Americas transformed not only Europe's ecosystems, but their own identities: think Ireland before potatoes, or Italy before tomatoes.In turn, the invaders from the Old World not only fell upon the women of the conquered New World, but also brought the seeds of other species, most notably wheat, barley and rye.This "ecological imperialism," to use a term coined by the American geographer Alfred Crosby himself, helped European colonizers to forever imprint their image on their colonies.
Some of the experiments turned out to be ludicrous, such as the fact that English gardens with hyacinths and daffodils never took root in their colony of India.In New York, the European starling -- now a ubiquitous pest -- was brought in because it was thought that if Central Park could be home to all the birds mentioned in Shakespeare's works, New York It will appear more cultivated.Later, some people felt that Central Park should be the garden of all the plants mentioned in Shakespeare's plays, so they planted primroses, absinthe, Indian cress, wild roses and wild primroses with lyrical moods—— The flowers are ready, only the Birnam Forest of King Macbeth is owed.
How similar can the fictional past of the Mannahatta Project be to the Manhattan Forest of the future?It's up to how North American soils are moved that persist long after the humans who moved them are gone.The New York Botanical Garden's herbarium includes one of the first specimens in the United States, which looks like a lovely lavender stalk.These are actually the purple seeds of quinces, which originally grew in the North Gulf region between the United Kingdom and Finland. In order to cross the Atlantic Ocean, merchant ships used the moist sand along the coast of Europe as ballast. The quinces are likely to be mixed with the sand Li came here.As trade with the colonies increased, merchant ships discarded their ballast bags before loading, and more and more purple quince was dumped on American shores.Once here, they swim about in streams and rivers, for their seeds stick to any dirty feather or fur they come in contact with.In the marshes near the Hudson River, the cattails, willows, and canary creeper grasses that provide food and shelter for waterfowl and muskrats grow so luxuriantly that even wild animals can hardly through.By the twenty-first century, purple quinces will bloom across Alaska, and ecologists fear it will fill the swamps, driving away the ducks, geese, terns and swans that live there.
Even before it was built as Shakespeare Gardens, the designers of Central Park, Olmsted and Vaux, had moved 500,000 trees, and of course 500,000 tons of sand, to improve the natural landscape, so Persia Exotic tree species such as ironwood, Asian cypress, Lebanese cedar and Chinese imperial paulownia and ginkgo are used to spice up the island.Once human beings disappear, native plants will compete with powerful alien species and take back their right to survive-they fight locally, and they always have some advantages at the right time and place.
Many foreign ornamental plants, such as the double rose, will die with the humans who introduced them, because they are sterile hybrids that must rely on grafting techniques to reproduce.Without a gardener to graft, they too will wither and wither.Other coddled "colonials," such as English ivy, were left to fend for themselves, although they were no match for their American relatives, cinnamon and poison ivy.
Still others are variant products of selective breeding.If they are lucky enough to survive, they will also be smaller in size and less in number.Fruit left unattended, such as apples imported from Russia and Kazakhstan, will live up to the fairy tale of Johnny Appleseed5.Nature's criterion for survival of the fittest is vitality, not appearance and taste, which makes them eventually rough and ugly.Apple orchards are no longer sprayed with pesticides. Except for a few survivors, other fruit trees are exposed to the local pests and diseases such as apple maggots and night crawlers. The land will soon be replaced by local hardwoods. recovered.The imported garden vegetables are not much better off.Dennis Stevenson, deputy director of the New York Botanical Garden, said it doesn't take long for sweet radishes from Asia to turn into wild, bad-tasting wild carrots as animals gobble up the last tasty carrots we grow clean and dry.Broccoli, cabbage, Brussels sprouts, and cauliflower will degenerate into identical broccoli ancestors, and will no longer be able to tell each other apart.The Dominicans planted dry corn in the middle of the Washington Heights Parkway, and the DNA of their offspring would eventually revert to teosinte, corn on the cob as thick as an ear of wheat.
Other invaders, such as metals such as lead, mercury and cadmium, are not washed out of the soil as quickly because they are heavy metals.One thing is for sure: when cars stop running and factories stop running, emissions stop.Over the next century, corrosion will periodically detonate time bombs left in oil tanks, chemical plants, power plants, and, of course, hundreds of dry cleaners.Gradually, bacteria will break down fuel residue, dry-cleaning solvents, and lubricants, turning them into harmless organic hydrocarbons—though, from pesticides to plasticizers to insulation, the artificial Artifacts have to exist for thousands of years until microbes evolve to degrade them.
Without acid rain, the surviving trees would have less and less pollutants to fight off, as chemicals are gradually being removed from the system.Over the centuries, trees began to absorb the degraded heavy metals, further diluting their concentrations through recycling and redeposition.After the plants die and rot and become the soil cover, these industrial toxic substances will be buried deeper, and the subsequent plants will continue and deepen this process.
Many of New York's rare tree species are endangered, if not dying, but not many have gone extinct. Around 1900, a plague of pests and disease arrived in New York with a shipload of Asian saplings, and all of the American chestnut trees were hit by the blight, but even this deeply mourned tree is still in New York Live in the old forest of the Arboretum—only the roots, to be exact.They take root, sprout shoots that reach two feet, get knocked down by the blight, and sprout again, and the cycle repeats.Perhaps one day, without the pressure of humans to survive, they will be able to develop resistance to this disease.Chestnut trees, once the tallest hardwoods in the forests of the eastern United States, will be revived next to hardy exotic species that may live here, such as Japanese barberry, eastern snake vine and, of course, ailanthus.The ecosystems here are man-made creations that will live on after we're gone; it's a hodgepodge of the world's flora that would never be the same if it weren't for us.Chuck Peters of the New York Botanical Garden thinks that's not a bad thing. "New York is a great city because of its cultural diversity. All people can contribute. But when it comes to botany, we hate exotic species. We love native species and hope that aggressive ones Foreign plants go back to their homeland."
He leans his running shoes against the glistening bark of a cork tree from Heilongjiang, China, growing among the last hemlock trees. "It may sound presumptuous, but maintaining biodiversity is not as important as maintaining the functioning of the ecosystem. What matters is that the soil be preserved, the water clean, the trees filter the air, and the trees grow tall enough to reproduce new saplings , so that nutrients from the forest don’t get lost to the Bronx River.”
He took a deep breath of the filtered air of the Bronx forest.A healthy and vigorous man in his early fifties, Peters has spent most of his life in the forest.His field research has shown that the wild palm hazel in the Amazon, the durian tree in pristine Borneo, and the tea tree in the jungles of Burma are no accident.Humans once lived there too.The wilderness swallowed them and their memories, but nature still left their traces.The above is an example.
In fact, since modern humans appeared on the earth, it didn't take long for human traces to appear in nature.Erik Sandersen's Mannahata project aims to return the island to what it was when the Dutch discovered it - before humans came here, it wasn't some kind of virgin Manhattan forest, because there was no forest at all. "Because before the Delawares came," Sanderson explained, "there was nothing here but half a mile of ice."
About 11,000 years ago, the last ice age retreated northward out of Manhattan, stopping in the spruce and larch regions south of today's Canadian tundra.Here were the temperate forests of eastern North America we know today: oak, hickory, chestnut, walnut, ironwood, elm, birch, sugar maple, sweetgum, sassafras, and wild hazel.In the clearings grew clumps of American plums, sumacs, rhododendrons, and honeysuckle, mixed with some ferns and flowering plants.Spartina and hollyhock are found in salt marshes.When the warm place was covered with plants, warm-blooded animals began to appear one after another, including humans.
Archeology has found little remains here, suggesting that the first New Yorkers were most likely nomadic people who camped out in search of berries, chestnuts and wild grapes.They hunted turkeys, grouse, mallard ducks, and white-tailed deer for food, but mainly by fishing.Schools of smelt, sprat and herring swim in the surrounding waters.Brook salmon swim into the streams of Manhattan.Oysters, mussels, clams, crabs and lobsters are plentiful, and it's easy to catch a bunch of them back.On the coast, a large number of mollusk shells abandoned by people became the first batch of human building materials.When Henry Hudson saw this land for the first time, the northern part of Harlem and Greenwich Village was still a green savannah, and the Delaware people here set fire again and again in order to plant crops. The land cleared.Researchers at the Mannahatta Project filled water in a fire pit left over from Harlem, and from what floated to the surface, they concluded that people used to grow corn, soybeans, squash and sunflowers here.In the past, most of the island was as lush and lush as the Białowieża virgin forest.Long before the Indians sold the land to the colonists for 60 Dutch guilders, the traces of modern people had been branded on Manhattan Island.
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In 2000, a mountain dog ran into Central Park.This is a sign that the future may be a repeat of the past.Later, two coyotes broke into the city, and a wild turkey.The return of New York City to its wild state may not necessarily wait for the day when people leave.
That first coyote was probably just a scout, and it got here over the George Washington Bridge.Jerry Del Tufer manages the bridge for the Port Authority of New York and New Jersey.He later took over the bridge connecting Staten Island to the mainland and Long Island.A structural engineer in his early forties, he thinks bridges are the loveliest things people can think of because they gracefully span ravines and make natural moats pass.
Del Tuffer himself is both sides of the ocean.His olive skin suggested he was from Sicily; he spoke like a true urban New Jersey native.Maintaining sidewalks and steel structures became his life's work.Young peregrine falcons are hatched each year on the tall George Washington Tower; and plants such as fearless weeds and ailanthus trees provocatively grow and bloom from metal structures far from the soil, high above the water ——All these make him feel very interesting.Nature's partisans were always sneaking up on his bridge.Their weapons and troops are ridiculously paltry compared to steel armor, but if you turn a blind eye to the countless birds that are everywhere, the results can be devastating, because their droppings can prompt those aerial The seeds take root and germinate, and also have the effect of dissolving the surface coating.Del Tufer faces off against an unarmed but indomitable foe whose ultimate strength is survival in the face of adversity.Nature, he admits, must be victorious in the end.
However, he will not see this day in his lifetime.最重要的是，他十分珍惜他和其他员工一起继承的遗产：他们的大桥是整整一代工程师的杰作，不过这些工程师不可能想到每天通过这些大桥的汽车竟会有三十多万辆，而且八十年之后，大桥竟然还能使用。 “我们的工作，”他对他的小组成员说：“是在向下一代人移交这笔财富的时候，使它们比我们接管时的状态更棒。”
二月的一个下午，他一边迎着小雪走向巴约讷大桥，一边用无线电和其他工作人员聊天。斯塔腾岛这一头道路的下侧是十分坚固的钢铁地基，它被注入到巨大的混凝土厚块中，而这厚块又被锚定在岩床中——桥墩部分承受了巴约讷大桥主桥跨一半的重量。向上凝视曲曲折折的负重I型标和支柱，半英寸厚的钢板、法兰片和几百万颗半英寸长的铆钉和螺栓把它们相互连接，让人不禁想起虔诚的朝圣者张口结舌地看着高耸入云的梵蒂冈圣彼得圆顶大教堂时的那种敬畏之感：这个伟大的杰作将在这儿百世永存。但是杰瑞·德尔·图弗清楚地了解这些大桥，没有人类的维护，它们终将倒塌。
这不会立即发生，因为大桥最大、最直接的威胁将随着我们人类的消失而不复存在。德尔·图弗说，最大的威胁并非是川流不息的车辆。
“这些大桥十分结实，来来往往的车辆好比是蚂蚁爬在大象的身上。”在二十世纪三十年代，还没有电脑来精确地测算出建筑材料的承受力，工程师们为谨慎起见，堆上了许多不必要的材质。“前辈给我们留下的大桥，其用料是超过实际需求的。三英寸粗的吊索中含有的镀锌钢丝就足以绕地球四周。即使其它的拉索都断裂，这一根就能够拉起整座大桥了。”
头号敌人是公路管理处每年冬天在路面上撒的除冰盐，这种贪婪的物质一旦除完冰，便开始吞噬钢筋。汽车上滴下来的汽油、防冻剂和融雪水将除冰盐冲进下水道入口和大桥裂缝中，维修人员必须查找出来并冲洗干净。没有了人类，也就没有了除冰盐。不过，如果没有人给大桥上漆，它肯定会生锈，生锈的范围还真不小。
最初，氧化作用会在钢板上形成氧化层，厚度得有钢板的两倍，甚至更厚些。氧化层能够减缓化学侵蚀的速度。彻底生锈、倒塌需要几个世纪的时间，不过纽约的大桥不需要等那么久就会塌陷。这是由金属的特性所决定的——它们承受不了不断结冰、不断融化的周期反复。钢铁不会像混凝土那样开裂，它们会热胀冷缩。事实上，钢铁大桥在夏天的时候会变长，所以它们需要伸缩节。
冬天，它们会收缩，伸缩节内部的空间变得更宽，各种各样的东西被风吹进来。到这时，天气回暖的时候，大桥膨胀的空间就没有之前那么大了。没人给大桥上漆，伸缩节中推满了零碎，而且生了锈，于是膨胀时所需的空间就比金属本身大多了。
“到了夏天，”德尔·图弗说：“不管你喜不喜欢，大桥都会比原先更大。如果伸缩节堵塞了，膨胀点就会转移到最脆弱的连接处，比如说两种不同金属连接的地方。”他指了指四块钢铁与混凝土桥墩的连接处。“比方说那里。斜梁与桥墩铆接处的混凝土将会开裂。再要么，几个季节一过，螺钉就会折断。最后，斜梁会滑出桥墩而坠下。”
所有的连接处都是相当脆弱的。德尔·图弗说，两块铆在一起的钢板之间形成的铁锈会造成严重的后果，要么是钢板弯曲，要么是铆钉断裂。巴约讷大桥这样的拱桥，或者用来通行铁路的曼哈顿“地狱之门”，是用料最多的大桥。它们在接下来的几千年中都不会出事，尽管穿过滨海平原下某个地质断层的地震波依然会缩短它们的寿命。（它们可能会比东河下面十四根加强钢筋加固的混凝土地铁隧道的寿命长些——其中通往布鲁克林的一条铁轨可以追溯到四轮马车的年代。一旦哪里裂开，大西洋的海水就会奔涌而入。）车水马龙的吊桥河桁架桥只能维持两三百年，等它们的铆钉和螺栓脱落的时候，整座大桥也就坠入了早就等待着的滔滔江水中了。
到了那时，会有更多的山狗顺着无畏的先驱者的足迹进入到中央公园中。鹿、熊，最后是狼将接踵而至，它们是从加拿大重新回到新英格兰地区的。有朝一日，这个城市的大桥差不多都坍塌了，曼哈顿新近的建筑也都已毁灭，因为随便哪个地方的渗漏都能抵达它们内部的加强钢筋，它们会生锈、膨胀，然后从混凝土外壳中破裂而出。老式的石头建筑，比如说纽约中央车站——当不再有酸雨腐蚀大理石的时候，它们会比所有闪闪发光的现代建筑保持得更长久。
高楼大厦的废墟中回荡着的是曼哈顿新生河流中青蛙唱的情歌。现在的河流中满是拟西鲱和海鸥扔下的贻贝。印第安核电站位于时代广场以北35英里处。青鱼和美洲西鲱已经回到了哈得逊河，不过它们有几代子孙得去适应下这个核电站渗出的放射性物质，因为那时它的加厚混凝土层已经剥落。几乎所有适应人类生活方式的生物都消失了。貌似无敌的蟑螂——它们来自于热带地区——很早之前就冻死在没有供暖设施的大楼中了。没有了垃圾，老鼠或是饿死，或是沦为在摩天大楼废墟中筑巢的肉食鸟类的盘中餐。
上涨的水面、潮汐和盐蚀作用取代了设计精巧的海岸线。海岸线围住了纽约市的五个区，河口和沙滩错落其上。没有人来挖泥疏浚，中央公园的池塘和蓄水池变成了沼泽。没有了食草动物，除非二轮马车和公园警察的马儿能够转变为野生动物继续生存下去。中央公园的草坪也消失殆尽。一片成熟的森林在这儿成形，侵入了从前的街道，覆盖了空空的地基。山狗、野狼、赤狐和山猫使得松鼠的数量趋于平衡；我们留下的铅已被分解，但生命力顽强的橡树依旧生活在这里，五百年之后，即使气候变得更为温暖，橡树和山毛榉也能成为这里的统治者。
早在那之前，野生的掠食者就已经瓜分了宠物狗最后的后裔，但老谋深算、野性难驯的家猫依旧活着，它们以星椋鸟为食。大桥倒塌了，隧道被洪水淹没，于是曼哈顿又一次成为一个真正的岛屿，驼鹿和熊游过变得更为宽敞的哈莱姆河，饱食着德拉瓦族人曾经采摘的浆果。
曼哈顿的金融机构永远倒塌了，几所银行的拱顶耸立在残垣断瓦之中；银行里的钱已经毫无价值，绝对安全了，上面甚至长出了霉菌。陈列着艺术作品的博物馆在建造之初考虑更多的气温调控，而非承重能力。停电后，博物馆便失去了保护。屋顶上的拱形结构最终渗漏，而这通常是从天窗那里开始的，博物馆的地下室也会囤满积水。湿度和温度不断变化，馆藏作品成为真菌和细菌的美食，当然也少不了一种臭名昭著的博物馆杀手——黑色地毯圆皮蠹饥饿的幼虫。一旦它们钻到其它地面，携带的真菌就会使得这个大都市的画作脱色和分解，以至面目全非。陶瓷制品保持得还不错，因为它们的化学构成类似于化石。只要没什么东西掉下来把它们砸碎，它们就等着土壤将它们掩埋吧，未来的考古学家会把它们当作出土文物。氧化腐蚀作用加厚了青铜塑像上的铜绿，但没有影响到青铜的外形。曼哈顿的一个博物馆管理员芭芭拉·埃佩鲍姆说：“这就是我们何以得知青铜时代的原因了。”
她还说，即使自由女神像沉入了海底，它的外形或许依然能保持完整，虽然会发生些化学变化，也有可能被海洋藤壶包裹得严严实实。这里对她而言是最安全的地方了，因为千万年之后的某个时间，任何矗立着的石墙都会倒塌，其中或许还包括1776年用曼哈顿的坚硬片岩建造起来的华尔街圣保罗小教堂。在过去的十万年中，冰川曾经前后三次把纽约铲平。除非有朝一日，人类用含碳燃料冶金最终导致大气层消失，失控的全球变暖现象将地球转变为金星那样的行星，否则冰川终究还是会在无从知道的某天再次降临。山毛榉、橡树和臭椿树构成的成熟森林会被铲平。史坦登岛上的福来雪基尔斯垃圾掩埋场上四堆高高的掩埋垃圾的土墩也会被夷为平地，大量顽固的聚氯乙烯塑料和人类创造的寿命最为持久的发明——玻璃——都被会碾成粉末。
冰川消退之后，某种人工制造的、颜色发红的浓缩金属先被是埋藏在冰碛中，最后进入了下面的地质层，样子乍一看像是电线线路和管道装置。随后它又改变方向来到垃圾场，回到了地面上。地球上进化而来或外星球迁居而来的工具制造者们或许会发现和使用这些金属，不过到了那时，再也没有谁会知道：这些金属并非自然生成，而是我们人类留下来的。