 Chapter One
Wetlands: Human History, Use, and Science
Wetlands, landscape features found in almost all parts of the world, are known as "the kidneys of the landscape" and "ecological supermarkets" to bring attention to the important values they provide. Although many cultures have lived among and even depended on wetlands for centuries, the modern history of wetlands is fraught with misunderstanding and fear, as described in much of our Western literature. Wetlands have been destroyed at alarming rates throughout the developed and developing worlds. Now, as their many values are being recognized, wetland conservation and protection have become the norm in many parts of the world. Wetlands have properties that are not adequately covered by present terrestrial and aquatic ecology, making a case for wetland science as a unique discipline encompassing many fields, including terrestrial and aquatic ecology, chemistry, hydrology, and engineering. Wetland management, as the applied side of wetland science, requires an understanding of the scientific aspects of wetlands balanced with legal, institutional, and economic realities. As interest in wetlands has grown, so too have professional organizations and agencies that are concerned with wetlands, as well as the amount of journals and literature on wetland science.
Wetlands are among the most important ecosystems on Earth. In the great scheme of things, the swampy environment of the Carboniferous period produced and preserved many of the fossil fuels on which our society now depends. In more recent biological and human time periods, wetlands have been valuable as sources, sinks, and transformers of a multitude of chemical, biological, and genetic materials. Although the value of wetlands for fish and wildlife protection has been known for a century, some of the other benefits have been identified more recently.
Wetlands are sometimes described as "the kidneys of the landscape" because they function as the downstream receivers of water and waste from both natural and human sources. They stabilize water supplies, thus ameliorating both floods and drought. They have been found to cleanse polluted waters, protect shorelines, and recharge groundwater aquifers.
Wetlands also have been called "ecological supermarkets" because of the extensive food chain and rich biodiversity that they support. They play major roles in the landscape by providing unique habitats for a wide variety of flora and fauna. Now that we have become concerned about the health of our entire planet, wetlands are being described by some as important carbon sinks and climate stabilizers on a global scale.
These values of wetlands are now recognized worldwide and have led to wetland conservation, protection laws, regulations, and management plans. But our history with wetlands had been to drain, ditch, and fill them, never as quickly or as effectively as was undertaken in countries such as the United States beginning in the mid-1800s.
Wetlands have become the cause celebre for conservation-minded people and organizations throughout the world, in part because they have become symptoms of our systematic dismantling of our water resources and in part because their disappearance represents an easily recognizable loss of natural areas to economic "progress." Scientists, engineers, lawyers, and regulators are now finding it both useful and necessary to become specialists in wetland ecology and wetland management in order to understand, preserve, and even reconstruct these fragile ecosystems. This book is for these aspiring wetland specialists, as well as for those who would like to know more about the structure and function of these unique ecosystems. It is a book about wetlands-how they work and how we manage them.
Human History and Wetlands
There is no way to estimate the impact humans have had on the global extent of wetlands except to observe that, in developed and heavily populated regions of the world, the impact has ranged from significant to total. The importance of wetland environments to the development and sustenance of cultures throughout human history, however, is unmistakable. Since early civilization, many cultures have learned to live in harmony with wetlands and have benefited economically from surrounding wetlands, whereas other cultures quickly drained the landscape. The ancient Babylonians, Egyptians, and the Aztec in what is now Mexico developed specialized systems of water delivery involving wetlands. Major cities of the world, such as Chicago and Washington, D.C., in the United States, Christchurch, New Zealand, and Paris, France, stand on sites that were once part wetlands. Many of the large airports (in Boston, New Orleans, and J. F. Kennedy in New York, to name a few) are situated on former wetlands.
While global generalizations are sometimes misleading, there was and is a propensity in Eastern cultures not to drain valuable wetlands entirely, as has been done in the West, but to work within the aquatic landscape, albeit in a heavily managed way. Dugan (1993) makes the interesting comparison between hydraulic civilizations(European in origin) that controlled water flow through the use of dikes, dams, pumps, and drainage tile, partially because water was only seasonally plentiful, and aquatic civilizations (Asian in origin) that better adapted to their surroundings of water-abundant floodplains and deltas and took advantage of nature's pulses such as flooding. It is because the former approach of controlling nature rather than working with it is so dominant today that we find such high losses of wetlands worldwide.
Wetlands have been and continue to be part of many human cultures in the world. Coles and Coles (1989) referred to the people who live in proximity to wetlands and whose culture is linked to them as wetlanders. Some of these cultures and users of wetlands are illustrated in eighteen photographs in this chapter (Figures 1.1 through 1.18). Figures 1.1 through 1.7 show human cultures or settings around the world that have depended on wetlands, sometimes for centuries. Figures 1.8 through 1.11 show some of the many food products that are harvested from wetlands while Figures 1.12 through 1.16 illustrate the use of wetlands as sources of fuel, building materials, and even household goods. Most recently, wetlands have become the foci for ecotourism in many developing and developed parts of the world (Figure 1.17 through 1.18).
Sustainable Cultures in Wetlands
The Camarguais of southern France (Fig. 1.1), the Cajuns of Louisiana (Fig. 1.2), the Marsh Arabs of southern Iraq (Fig. 1.3), many Far Eastern cultures (Fig. 1.4), and the Native Americans in North America (Figs. 1.5 and 1.6) have lived in harmony with wetlands for hundreds if not thousands of years. These are the true wetlanders. For example, the Sokaogon Chippewa in Wisconsin have, for centuries, harvested and reseeded wild rice (Zizania aquatica) along the littoral zone of lakes and streams. They have a saying that "wild rice is like money in the bank." Wetlands were often used as places of cultural solitude and reverence, as with the Mont St. Michel, a Benedictine monastery, built between the 11th and 16th centuries in northern France (Fig. 1.7).
Food from Wetlands
Domestic wetlands such as rice paddies feed an estimated half of the world's population (Fig. 1.8). Countless other plant and animal products are harvested from wetlands throughout the world. Many aquatic plants besides rice such as Manchurian wild rice (Zizania latifolia) are harvested as vegetables in China (Fig. 1.9). Cranberries are harvested from bogs, and the industry continues to thrive today in North America (Fig. 1.10). Coastal marshes in northern Europe, the British Isles, and New England were used for centuries and are still used today for grazing of animals and hay production.
Wetlands can be an important source of protein. The production of fish in shallow ponds or rice paddies developed several thousands of years ago in China and Southeast Asia, and crayfish harvesting is still practiced in the wetlands of Louisiana and the Philippines. Shallow lakes and wetlands are an important provider of protein in many parts of sub-Saharan Africa (Fig. 1.11).
Peat and Building Materials
The Russians, Finns, Estonians, and Irish, among other cultures, have mined their peatlands for centuries, using peat as a source of energy on small-scale production (Fig. 1.12) and in large-scale extraction processes (Fig. 1.13). Sphagnum peat is now harvested for horticultural purposes throughout the world. In southwestern New Zealand, for example, surface Sphagnum has been harvested since the 1970s for export as a potting medium (Fig. 1.14). Reeds and even the mud from coastal and inland marshes have been used for thatching for roofs in Europe, Iraq, Japan, and China, as well as wall construction, fence material, lamps, and other household goods (Figs. 1.15 and 1.16). Coastal mangroves are harvested for timber, food, and tannin in many countries throughout Indo-Malaysia, East Africa, and Central and South America.
Wetlands and Ecotourism
A modern version of wetland use is through ecotourism. Wetlands have been the focus of several countries' attempts to increase tourist flow into their countries (Figs. 1.17 and 1.18). The Okavango Delta in Botswana is one of the natural resource jewels of Africa, and protection of this wetland for tourists and hunters has been a priority in that country since the 1960s. Local tribes provide manpower for boat tours (in dugout canoes called mokoros) through the basin and assist with wildlife tours on the uplands as well. In Senegal, west Africa, there is keen interest in attracting European birder tourists to the mangrove swamps along the Atlantic coastline. The advantage of ecotourism as a management strategy is obvious-it provides income to the country where the wetland is found without requiring or even allowing resource harvest from the wetlands. The potential disadvantage is that if the site becomes too popular, human pressures will begin to deteriorate the landscape and the very ecosystem that initially drew the tourism.
Literary References to Wetlands
With all of these valuable uses, not to mention the aesthetics of a landscape in which water and land often provide a striking panorama, one would expect wetlands to be revered by humanity; this has certainly not always been the case. Wetlands have been depicted as sinister and forbidding, and as having little economic value throughout most of history. For example, in the Divine Comedy, Dante describes a marsh of the Styx in Upper Hell as the final resting place for the wrathful:
Thus we pursued our path round a wide arc of that ghast pool, Between the soggy marsh and arid shore, Still eyeing those who gulp the marish [marsh] foul. -Dante Alighieri
Centuries later, Carl Linnaeus, crossing the Lapland peatlands, compared that region to that same Styx of Hell:
Shortly afterwards began the muskegs, which mostly stood under water; these we had to cross for miles; think with what misery, every step up to our knees. The whole of this land of the Lapps was mostly muskeg, hinc vocavi Styx. Never can the priest so describe hell, because it is no worse. Never have poets been able to picture Styx so foul, since that is no fouler. -Carl Linnaeus, 1732
In the 18th century, an Englishman who surveyed the Great Dismal Swamp on the Virginia-North Carolina border and is credited with naming it described the wetland as:
[a] horrible desert, the foul damps ascend without ceasing, corrupt the air and render it unfit for respiration.... Never was Rum, that cordial of Life, found more necessary than in this Dirty Place. -Colonel William Byrd III (1674-1744), "Historie of the Dividing Line Betwixt Virginia and North Carolina" in The Westover Manuscripts, written 1728-1736, Petersburg, VA; E. and J. C. Ruffin, printers, 1841, 143 pp.
Even those who study and have been associated with wetlands have been belittled in literature:
Hardy went down to botanise in the swamp, while Meredith climbed towards the sun. Meredith became, at his best, a sort of daintily dressed Walt Whitman: Hardy became a sort of village atheist brooding and blaspheming over the village idiot. -G. K. Chesterton (1874-1936), Chapter 12 in The Victorian Age in Literature, Henry Holt and Company, New York, 1913
The English language is filled with words that suggest negative images of wetlands. We get bogged down in detail; we are swamped with work. Even the mythicalbogeyman, the character featured in stories that frighten children in many countries, may be associated with European bogs. Grendel, the mythical monster in one of the oldest surviving pieces of Old English literature and Germanic epic, Beowulf, comes from the peatlands of present-day northern Europe:
Grendel, the famous stalker through waste places, who held the rolling marshes in his sway, his fen and his stronghold. A man cut off from joy, he had ruled the domain of his huge misshapen kind a long time, since God had condemned him in condemning the race of Cain. -Beowulf, translated by William Alfred, Medieval Epics, The Modern Library, New York, 1993
Hollywood has continued the depiction of the sinister and foreboding nature of wetlands and their inhabitants, in the tradition of Grendel, with movies such as the classic Creature from the Black Lagoon (1954), a comic-book-turned-cult-movie Swamp Thing (1982), and its sequel Return of the Swamp Thing (1989). Even Swamp Thing, the man/monster depicted in Figure 1.19, evolved in the 1980s from a feared creature to a protector of wetlands, biodiversity, and the environment. But as long as wetlands remain more difficult to stroll through than a forest and more difficult to cross by boat than a lake, they will remain misunderstood ecosystems to the general public without a continued effort of education.
Wetland Destruction and Conservation
Prior to the mid-1970s, the drainage and destruction of wetlands were accepted practices around the world and were even encouraged by specific government policies. Wetlands were replaced by agricultural fields and by commercial and residential development. Had those trends continued, the resource would be in danger of extinction. Some countries and states such as New Zealand and California and Ohio in the United States have reported 90 percent loss of their wetlands. Only through the combined activities of hunters and anglers, scientists and engineers, and lawyers and conservationists has the case been made for wetlands as a valuable resource whose destruction has serious economic as well as ecological and aesthetic consequences for the nations of the world. This increased level of respect was reflected in activities such as the sale of federal "duck stamps" to waterfowl hunters that began in 1934 in the United States (Fig. 1.20); other countries such as New Zealand have followed suit. Approximately 2.1 million hectares (ha) of wetlands have been purchased or leased as waterfowl habitat by the U.S. duck stamp program alone since 1934. The U.S. government now supports a variety of other wetland protection programs through at least a dozen federal agencies; individual states have also enacted wetland protection laws or have used existing statutes to preserve these valuable resources.
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