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INTRODUCTION
Оглавлениеeverlasting swamps
‘Everything here depends on the water, but the government is taking our water. They are giving it to foreign farmers. The lakes don’t fill properly now.’ Daouda Sanankoua, Mayor of Deboye in Mali, was describing the plight of his constituents in the heart of the Inner Niger Delta, on the edge of the Sahara Desert. Their water, collecting in a wetland the size of Belgium, once nurtured a great civilization around the fabled city of Timbuktu. Today, two million people depend on its fish, and its waters washing across croplands and pastures. Millions of European birds migrate to the delta each winter. But dams upstream are diverting water away from the delta. ‘The wind is driving sand into our village,’ said one of Sanankoua’s people. ‘Most of our fields are gone.’1
With another dam awaiting construction, hydrologists say that soon every year on the delta could be a drought year. Yet the people here are fighting the encroaching desert. They are planting trees and grasses, channelling water to fields, creating vegetable gardens, and digging fish ponds. Not a drop of water must go to waste, they say. They want the dams upstream to be managed to allow the delta to continue to flood each wet season. Without the annual flood, the prognosis for the wetland, its people and its birdlife, is bad. As Sanankoua put it, ‘a wetland is nothing without its water.’
From the peat bogs of Ireland to the bayous of Louisiana; from the flooded forests of Cambodia to the permafrost of Siberia; from the mangroves of the Ganges Delta to the ‘everlasting swamps’ of the Nile; and from the marshes of the Brazilian Pantanal to the boggy upland pastures of Tibet, wetlands are in-between and ever-changing worlds. Sometimes wet and sometimes dry, sometimes land and sometimes water, sometimes saline and sometimes fresh; they change character with the seasons, or may lie dormant for decades before bursting into life.
The Bible says that God created the world by dividing the land from the water. If so, He forgot about wetlands. For in wetlands rivers have no fixed banks, water oozes through soil, and silty soil courses through water. Fish live in trees and land mammals swim for their lives. Yet despite their ephemeral and contradictory nature, wetlands are our planet’s richest natural resource. Wetlands have extraordinary natural abundance. And that abundance helps make our world. Fertile with silt and rich in wildlife, wetlands were the first and most important sources of wealth for early human civilizations. From ancient Egypt to Angkor Wat in Cambodia, and Mesopotamia to Timbuktu, our earliest urban societies grew on and beside wetlands.2
Wetlands regulate and govern the hydrology of most of the world’s river systems and determine access to water for billions of people. They nurture fisheries and water crops, maintain dry-season pastures, and provide fresh water and flood protection far downstream. They make deserts liveable by cooling summers, warming winters, and wetting dry air. They maintain river flows and top up groundwaters. They protect shorelines from high tides and storms. They simultaneously provide irrigation and drainage. They are the planet’s biggest terrestrial carbon store. They are home to a third of all known vertebrate species.3 They even reduce pollution by soaking up nutrients and toxins.
Finally, many wetlands are among the last great areas of the planet held in common by their communities. Their unfenced wealth is open to nomads in search of pasture for their animals, but also to the poor, the distressed, the marginalized and the banished. In war-torn and drought-stricken lands, they may provide security and the next meal for those in extremis.
WETLANDS CONJURE UP MANY IMAGES: lazy lagoons, gardens of Eden, mysterious mist-shrouded Shangri Las, or shimmering lakes. The Ramsar Convention on Wetlands came up with forty-two types.4 But categorizing them is a thankless task, and this book won’t get ‘bogged down’ in definitions. Instead, as we journey from source to sea in search of their past, present, and future, we will revel in their sheer variety and the range of services they provide for nature and for us.
All are rich in wildlife, of course. Insects, birds, and fish especially. Seemingly isolated wetlands across the world are parts of a network of watery places that sustain migrating water birds. Travelling from North to South America; from Europe to Africa; across Asia; and from the poles to the tropics, birds depend on these vital stepping stones to rest, feed, and breed. Remove one wetland and you may decimate bird populations thousands of kilometres away.
But wetlands provide myriad human services too. We will visit many peat bogs, for instance. These large waterlogged stores of plant carbon occur everywhere from mountain valleys to coastal swamps, and from Arctic tundra to tropical rainforests. They help protect the planet from the worst of climate change, but if drained or burned they can rapidly become part of the climate problem. We will travel to dry lands, such as the African Sahel, where the precarious fate of the Inner Niger Delta, Lake Chad, and the Sudd swamp on the Nile is a matter of life and death for tens of millions of people. On coasts, we will see how the salty waters of river deltas, estuaries, mangrove swamps, mudflats, lagoons, and salt marshes, sustain fisheries and water crops, and defend hundreds of millions of people from the ravages of the oceans.
Wetlands are also part of the great river systems that flow from mountain peaks to the oceans. In the modern world, we too often think of rivers as water conduits cut off from the surrounding land. But natural rivers meander and divide, stop off in lakes and marshes, form deltas and spread across verdant floodplains. Most rivers retain at least some of these features. Rivers are wetlands in their own right.
Canada’s mighty River Mackenzie connects no fewer than three large deltas that punctuate its path to the Arctic Ocean, and a huge floodplain known as the Mackenzie Lowlands. In Asia, the Ganges surges from glacial lakes in the Himalayas, through the swamps and flooded grasslands of the Terai and its wide floodplain – one of the most densely populated regions in the world – to the Sundarbans, the world’s largest mangrove swamp. The upper reaches of the River Paraguay in South America pass through the Pantanal, the world’s largest wetland, before flowing through others almost as large to the Paraná Delta. In Central Europe, the Danube passes through wetlands left undisturbed by the Cold War on its journey to its own delta, Europe’s largest, and the Black Sea.
Wetlands have few fixed boundaries. They change as the water comes and goes. So global estimates of their total extent vary widely. But at any one time, they certainly exceed the size of the United States or China. In the recent past, these watery commons have been Cinderella ecosystems, shunned or forgotten. In European folklore and literature, swamps, mires, bogs and moors have been places to be feared, where monsters roam and diseases lurk. ‘As you value your life or your reason, keep away from the moor,’ said Sir Charles Baskerville in Arthur Conan Doyle’s Sherlock Holmes novel, The Hound of the Baskervilles. In British criminal history, few episodes loom as large as the 1960s child slayings known as the ‘Moors murders’, because of the children’s bleak final burial ground.
No wonder that we have long sought to banish wetlands from our landscapes. ‘Drain the swamp’ is an old cry. Ever since the Dutch began installing windmills to pump out the boggy places where the Rhine met the North Sea, engineers have been on the case. During the twentieth century, around two-thirds of all the world’s wetlands – swamps, bogs, river banks, lakes, mires, billabongs, oases, deltas, mangroves, lagoons, ponds, mudflats, fens, floodplains and the rest – were drained, dammed and dyked to death. They are still disappearing three times faster than rainforests, but with far less protest.5
In their places are cities, infrastructure and farmland – all released from the menace of flooding. Or so it is claimed. For the protection is often illusory. We now increasingly realize that wetlands prevent more floods than they cause. And rather than being badlands, they are a good thing, nourishing landscapes and maintaining river systems. Just as the jungles of past nightmares are now rainforests to be cherished, so the watery wastes are being reimagined as places teeming with natural wealth, vital to biodiversity and human welfare, and helping to resist climate change. As the first President Bush declared as long ago as 1989, ‘It’s time to stand the history of wetlands destruction on its head; from this year forward, anyone who tries to drain the swamp is going to be up to his ears in alligators.’6
Our new-found appreciation of wetlands is tapping into old roots. In much of the world, wetlands have always been important cultural beacons. Many are sacred places. Lake Loktak in north-east India is the spiritual home of the Meitei people.7 The Wapichan in Guyana chart their ancestry in their flooded grasslands. For Christians, the founding story of humanity begins in the Garden of Eden, widely regarded as the Mesopotamian Marshes of modern-day Iraq. And even where that religious association is lost, we have always found beauty in their open spaces: whether the Lake District in England, southern Africa’s Okavango Delta, India’s Kerala Backwaters, Peru’s Lake Titicaca or the Florida Everglades.
But the wealth of wetlands remains, literally and metaphorically, hard to grasp. They could yet slip through our fingers. The fluid, unfenced and often unowned attributes of wetlands are difficult to reconcile with a modern world that values certainty in nature more than variability, where floods are seen primarily as destructive, and where private property is the universal currency. Despairing of exploiting the moving feast, our first instinct too often remains to enclose, privatize, and tame; to dam, drain, dyke, dredge, canalize, or concrete them over.
This is madness. As one assessment by a collaboration of international scientists concluded, ‘our relentless conversion and degradation of remaining natural habitats – including wetlands – is eroding overall human welfare for short-term private gain’.8 It is simply a myth to imagine that a degraded environment is the inevitable price of development. Quite the contrary. In the Anthropocene, we need wetlands and the wealth they provide at least as much as we need rainforests or healthy oceans.
So, besides charting the losses and exposing the continuing threats that wetlands face in the twenty-first century, the central purpose of this book is to explore and celebrate ways that the world’s wetlands can and must be secured and restored, for a healthy planet and for healthy and well-fed humans. The stories told here are at least as much about wetlanders as wetlands.
Many conservationists would like to keep wetlands for nature alone. Especially for their birdlife, which happily also commands high value among tourists. In places, that remains possible. But wetlands are often too important to the people that live in and beside them to be set aside for nature alone. They provide sustenance for millions, and refuges and security for many poor and marginalized communities. They maintain river systems on which billions, often far downstream, depend. Moreover, as shared and commonly owned resources, their protection and restoration can sometimes help nurture peace – between communities and even between nations, such as in the Balkans, as we shall see.
The challenge today is to recognize the vast natural capital tied up in wetlands, and to access that capital by reinventing wetlands for the modern world, with new systems of governance, new economic roles, new crop regimes, and, if necessary, new hydrology. It means managing rivers and lakes to restore natural flows and reconnect them with their floodplains. In many places, it also means taking advantage of entirely artificial and accidental wetlands that have sprung up across the landscape, and to recognize that urban wetlands are no longer an oxymoron.
Wisely used, wetlands help development and lift people out of poverty. Indeed, this can be the key to their conservation. For if we don’t value wetlands, if they don’t contribute to the local economy and the livelihoods of their inhabitants, then they will be forsaken and lost.
Of course, a commitment to ‘wise use’ raises as many questions as it answers. Does it mean allowing in a few fishers and reed cutters? Or how about cattle herders? And if them, then why not farmers and charcoal burners? Should the arbiters of what is meant by wise use be economists, weighing farm profits against a dollar value attached to ecosystem services? Or ecologists, who may have a very different way of measuring wetland wealth? Or how about the wetland residents themselves, and the millions who can benefit from silt supplies and flood protection all the way to the ocean? No answer will fit all circumstances, but many people will conclude from the examples in this book that sustainable wetland use will only be achieved when those who live in and around them, and depend on their resources, have the final say.
What is certainly true is that if we want water for all we must take care of the wetlands that are the sources of most of our water, and rediscover ways to capture and store water in our landscapes. If we want safe coastlines, we need to revive the deltas and lagoons, mangrove swamps, and salt marshes that are nature’s flood defences. If we want to reverse land degradation, restore natural capital and improve the lives of wetland inhabitants, then we need to block up drains, tear down dykes, and guarantee that free-flowing rivers can deliver their life-giving flood pulses. Wetlands matter.