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An Unwanted Legacy

By all accounts, the wetlands in the Zambezi region that Livingstone struggled through are still there. A mosaic of seasonally wet grasslands interspersed with seasonally flooded forests and scattered small permanent papyrus swamps is encountered along the Kafue Flats and the Kafue River (Map 8, p. 213). This is a major tributary that heads south, flowing through the Copperbelt before it joins the Zambezi.

One interesting thing about the region is the constancy of species in these wetlands. The botanist, range manager, or ecologist traveling the length of Africa soon becomes used to seeing the same wetland plants. It makes little difference whether you are in the swamps of East and Central Africa or the Sudd, the reed grass (Phragmites), bulrush (Typha), and papyrus (Cyperus) prevail. Sometimes the three are on their own or sometimes in combination with other Africa-wide species such as the water-tolerant grasses Echinochloa, Oryza, Miscanthidium, and Leersia, as well as the floating so-called hippo grass, Vossia, common in deep water.

In the Zambezi Basin these shallow, seasonally saturated, grassy wetlands are called “dambos,” a local term meaning a very wet depression. Although Livingstone thought they were endless, dambos make up only 20% of the plateau regions of Central and Southern Africa. Even so, their presence is impressive by any standard.

While most dambos are waterlogged for at least a portion of the year, quite a few dry out at the surface during the four- to six-month dry season. However, the sponge-like center stays moist, and that sustains the aquatic grasses and reeds that are typical of this monotonous landscape. The only relief from these acres of reed beds is the shade that comes from trees and bushes that grow up on termite mounds or the upper drier slopes of the dambos away from the bottomland. Unfortunately, the shade provided by these trees and bushes also serves as a habitat for the tsetse fly, against which the local herders and farmers have to defend themselves.

The wetlands and aquatic environments in the region, as impressive as they are today, are no longer the wild, unsullied ecosystems of 150 years ago. The changes that have occurred are due mostly to man’s activities. About 10% of the dambos are farmed during the dry season when the edges dry out enough to be cultivated. In the wet season the same areas are fished, while year-round 40% of the seasonal grassland margins are grazed, and 30% have been converted to national parks and are reserved for eco-tourism.1

Within limits, this sort of multiuse of the land is sustainable and is considered a desirable goal. It is only when activities get out of hand that the trouble begins. Large-scale clearance of dambos, excessive poaching, and overgrazing or overfishing, for example, will upset the balance. Another large difference between the time of Livingstone and today is the discovery of extensive deposits of copper and cobalt, the mining of which has created the pollution that now threatens the region. Almost 40% of the people of Zambia depend on the Kafue River for their well-being and are thus affected.

Mineral deposits have made Zambia one of the most industrialized countries in Africa. However, any advantage this may have given the country was negated when world copper prices collapsed in 1975, damaging the Zambian economy. As a result, a very high percentage of the population still lives below the poverty line. In recent years the copper mines, now privatized, have benefited from a rebound in copper prices. That and a maize bumper crop have helped turn the economy around. Foreign investment has also helped. China has invested close to $3 billion in the Zambian economy, according to recent government figures.

The Dambos: Overworked and Underpaid

As Livingstone found, the Zambezi Basin is blessed with a significant array of swamps and dambos (Map 8, p. 213). Although these ecosystems function here in the same way as wetlands in many other places in Africa, in this region they have been tasked with double duty. Not only have they had to work hard at recharging the water table and trapping silt and sewage, but for the last 80 years they have also had to clear heavy metals from mine wastewater.

The heavy metals referred to are iron, cobalt, copper, manganese, molybdenum, and zinc, all metals required in trace quantities by living organisms, but which in excessive levels can be damaging. Others, such as vanadium, tungsten, cadmium, mercury, plutonium, and lead, are of no use to the human body, and their accumulation over time can cause serious illness.

Mine waste contains elevated concentrations of these metals because mine wastewater is acidic. It gets that way because ores often occur in sulfide form; exposure of the sulfide ores to oxygen and water during the process of mining leads to the formation of trace amounts of sulfuric acid, enough to leach out heavy metals.

While the mines are in operation, the water is pumped and drained from the work areas. But once mines are abandoned, the water table returns to normal and acid mine waste is left to seep out unhindered into the local water bodies. Thus the intense mining and ore-processing activities in the Copperbelt produced quantities of wastewater that were often discharged into the dambos, where the trapping of metals, especially cobalt and copper, has gone on for years.

Since the process of trapping heavy metals is dependent on the pH of the water, the best retention happens when wastewaters have been neutralized, a practice that was often neglected. Consequently, for the wetlands the job has been all uphill; and although they succeeded in trapping insoluble compounds into their oxygen-poor peat, mud, and sediments, they were overwhelmed in the process. As a result, contamination can now be detected 400–500 miles downstream in the Kafue River before it joins the Zambezi.2

The Copperbelt wetlands have been receiving wastewater from mining activities for many years, during which time wetland plants were left to die and be recycled in the peat. Thus massive accumulation of toxic metals has been buried in the swamp sediment.

Looked at another way, one could say that the wetlands provided a respite during the past 80 years, during which period appropriate environmental rules and regulations should have been put in place and enforced by the responsible agencies. Mining companies should have installed water-quality monitoring systems in order to manage toxic sediments and prevent their buildup into untended heaps. Proper maintenance of mine-waste dumps to neutralize acid waste and prevent toxic runoffs should have been part of normal mine operation. Instead, mining and smelting have saddled Zambia’s Copperbelt with a huge environmental legacy.3

In 2006, according to a survey published by the Blacksmith Institute, an organization monitoring pollution in the developing world, Kabwe, about 80 miles north of the capital Lusaka and home to 300,000 people, was designated Africa’s most polluted city. It also has the dubious distinction of being ranked as the world’s fourth most polluted site.

Today, all of the interventions needed to make the river basin a more wholesome place to live will be expensive and difficult to install. Meanwhile, as pointed out in a recent review of the region, “the Zambian Copperbelt is burdened by an economic and environmental paradox. On one hand, development and growth of the mining industry is crucial in addressing Zambia’s social and economic plight. On the other hand, all natural drainage routes of mine effluent inevitably enter the Kafue River, often passing through natural wetlands, which form the headwaters of this system.”4

Since the alternatives to dambos are few, Zambia must face up to another problem: the wetlands that have previously acted as filters could still harbor dangers. The metals could again become mobile if the dambos in this region were drained for cultivation, or if they were to become acidified for any reason. Any action of this sort would flush metals out of the system into a local river where they could become a major source of pollution years after they were released from the mines.

Solutions

Fortunately, the dambos in the Copperbelt have been well studied, first by a team from Oxford University, including Constantin von der Heyden and Mark New of the Centre for Water Research and the School of Geography in Oxford, and more recently by a team from the Palacký and Charles Universities in the Czech Republic, headed by Dr. Ondra Sracek.5

It is obvious from their work that, for economic reasons, the dambos within the Zambezi Basin must continue to act as filter swamps for years to come, in which case mines would be better off using managed or constructed wetlands in combination with the dambos in order to obtain adequate water treatment. Also, before it is discharged, mine wastewater should be neutralized as a mandatory measure. Although wetlands often contain carbonate-rich groundwater with a high capacity for pH buffering and thus some neutralization will occur naturally, their efficiency as filters is greatly increased if mine wastes are neutralized beforehand.

Though older dambos are no longer as effective as they used to be, von der Heyden and New showed that older, saturated dambos can successfully be rejuvenated by giving them a rest. Also, as mentioned earlier, the filtration by wetlands can be made even more effective if the plant matter is harvested to remove the nutrients and heavy metals from the system.

Papyrus to the Rescue

The ultimate solution in the Copperbelt is perhaps to modify existing wetlands or construct new ones that would allow the deposited metals to be filtered out and disposed of. This is standard practice in conventional sewage-treatment systems. Your local cesspool man is a good example: he pumps out your backyard septic tank, hauls the sludge away for drying (“dewatering”), and disposes of it as mulch.

The problem in the Copperbelt is that many of the wetlands concerned are dominated by rooted plants, such as reed grasses and cattails. That vegetation would have to be cleared away in order to get at the sediments underneath, in which the metals are trapped. This would mean destroying the wetland. One way around this is to harvest the top part of the reeds for forage or mulch and let the base re-grow. But clearing tons of heavy metal from sediments is a major obstacle to overcome, and harvesting alone will not do it.

One attractive scheme that might work in the Zambezi wetlands comes from a recent study by Tom Headley and Chris Tanner, scientists working at the National Institute of Water and Atmospheric Research in Hamilton, New Zealand. They set out to design a low-maintenance system to remove heavy metals from stormwater before it drains into local water bodies. The method they selected is a four-part system composed of: (1) a settling basin where coarse material settles to the bottom, following which the water flows into (2) a basin with a floating mat of wetland vegetation, where fine particles and heavy metals are removed; the water then flows on to a third basin that contains (3) a small pond surrounded by a rooted wetland, where removal of nutrients and more metal takes place, after which the water flows down (4) a cascade to aerate it before it is released.

The beauty of their system is that the floating wetland plants in the second basin can be moved aside to allow the metal-containing sediments in the sludge to be pumped out.

How would that work in Zambia? First of all, a floating wetland that grows in quantity in the Zambezi River Basin and that has proved itself a strong remover of heavy metals is already at hand: papyrus. If several Copperbelt dambos were restructured to allow deep water to be retained and papyrus was encouraged to cover the surface, a perennial floating system would be created that might be more useful as a filter swamp than the classic dambo. Papyrus has the advantage in that the floating matrix of the swamp and the roots produces peat as well as a fine, light sediment that falls to the bottom of the swamp as sludge. This can be pumped out and carted away, dewatered, and disposed of. Also, the stems of papyrus, which we know can take up copper and cobalt in quantity, can be harvested and, instead of being used as mulch or fodder, can be mechanically chopped up or pulped to produce building materials, such as softboard.

This would remove the metals from the food cycle and would produce a cheap, useful byproduct. A rigid fiberboard was manufactured from dried papyrus stems and successfully sold in Uganda and Rwanda in the ’70s and ’80s, but both production units succumbed to competition from cheap imports.6 With some sort of tariff protection in Zambia, it just might work.

Such a papyrus-based system designed specifically for the Copperbelt would be an economic alternative to the conventional sludge and sediment removal system used by industry, and it would generate a sustainable and productive wildlife habitat, a haven for migratory and indigenous birds and animals, all things that I’m sure Mother Nature—and the people who live in the region—would approve of.

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Among the many things buried in Zambia, besides Dr. Livingstone’s heart and tons of heavy metals, are perhaps the remains of a living fossil, an animal called “Emela-Ntouka” that was said to have been slaughtered in 1933 by Waushi tribesmen along the shores of the Luapula River, which connects Lake Bangweulu to Lake Mweru (Map 5, p. 141).

Past history and observations today tell us that the African swamps are places of natural refuge. We are also told that they harbor great numbers of higher and lower plant and animal species, but, as in so many other ecosystems throughout the world, there is still much work to be done in finding and identifying species yet undescribed. The importance of such work is paramount, but it must also be conceded that in the swamps there is a special case for continuing work on species of the fantastic variety—that is, monsters, fictitious or real.

These creatures serve a purpose, as they have down through history: providing a scare factor that is of practical use. For example, what better addition to the existing papyrus swamp flora than the prehistoric elephant Moeritherium, that smooth-skinned, four-foot-long denizen of the swamps of Faiyum, the place in Egypt where papyrus swamps were common enough. With its flexible upper lip and snout, it spent most of its time half-submerged in the primeval Egyptian swamps, perhaps resting—much like the sitatunga does today—entirely submerged in a papyrus swamp with only its nostrils above water.

Knowing that such a creature was capable of making your next step your last step if by chance you trod on it, and if it rose up in response with its razor-sharp, hippo-like tusks pointed at you while it charged with the speed and force of a Volkswagen, you might believe that it is as useful a conservation measure as any fence or ranger patrol.

The Moeritherium is wishful thinking, as it is known to us only through some fossil teeth. On the other hand, cryptozoologists tell us that the Emela-Ntouka lives today. And not only is it living and hiding in the swamps of Lake Bangweulu, it is brownish-gray in color with a heavy tail and a body of the shape and appearance of a rhinoceros, having one long horn on its snout. It is about the size of the largest living terrestrial animal, the African Bush Elephant.

At 13,000–20,000 lbs, whether real or imaginary, we are looking at a formidable scare factor.

Could any branch of science be more appropriate to the study of swamp monsters than cryptozoology? More important, this “study of hidden animals” is now in a bid to be recognized as a branch of zoology that includes looking for living examples of animals that are considered extinct (such as dinosaurs), or animals whose existence lacks physical support but which appear in myths, legends, and first, second, or thirdhand reports. It is a discipline determined to be taken seriously. By conducting their work with scientific rigor, an open mind, and an interdisciplinary approach, cryptozoologists intend to prove themselves by bringing home the “real” thing, or “cryptid.”

This pivotal cryptozoological event actually came to pass in 1938 when a Coelacanth was discovered off the eastern coast of South Africa. A fish considered to be the “missing link” between fish and tetrapods, they were believed to have gone extinct 65 million years ago. So there is a case for the existence of undiscovered, unlikely, or fantastic creatures. And further, many of the scientists involved in cryptid research have credentials. They also have sound reputations built on real fieldwork. But in order to succeed, they must have a modicum of boldness and flair, otherwise it would be impossible to defend their work, which is often based on folk tales with only a few tiny grains of truth.

The biologist and explorer Dr. Roy P. Mackal, who has gathered details while on two expeditions in the Congo region, is a good example of a crytozoologist. In his 1987 book A Living Dinosaur, Mackal noted that the live sightings of the Emela-Ntouka did not report a neck frill, which he would have expected on a ceratopsian. Furthermore, the Ceratopsia are absent from Africa’s fossil record. On the basis of this kind of evidence, the cryptozoologist and author Loren Coleman suggested that the Emela-Ntouka is a new species of semi-aquatic rhinoceros.

The intriguing thing about African aquatic cryptids is that there are so many of them and they live in papyrus swamps. Further west and north within the Congo wetlands and swamp forests, for example, we have reports of: the Mokele-mbembe, a living sauropod dinosaur 16 to 32ft long that lives in the Likouala swamp region; a giant turtle in Lake Tele whose shell is 12 to 15ft in diameter; and the Mbielu-mbielu-mbielu or Nguma-monene, snake-like animals 130 to 195ft long with a serrated ridge running down their backs like that of a crocodile.

Any of these would serve as the ideal protector of the local papyrus swamps. We find proof of this in the words of the world-famous zoologist and biologist Ivan T. Sanderson, who in 1931, while paddling up a river in the heart of Africa, recalled the experience: “I don’t know what we saw, but the animal, the monster, burned itself into my retinas. It looked like something that ought to have been dead millions of years ago. As a scientist, I should have been happy, of course, but this encounter was so frightening, so nasty that I never want to see it again.”

The modern factor of pollution may change the cryptid game considerably. Instead of strange creatures still around from an ancient past, these would be mutated creatures of the future. After all, the idea has been around for some time that out of the swamp slime from pollution will come a new cryptofauna, a concept that forms the basis for the fictional Teenage Mutant Ninja Turtles from the storm sewers of New York City by way of Mirage Studios in 1984.

The same concept livened up the world of Charles Dickens 160 years ago, at a time when people were just beginning to be concerned about what else might arise from the mess that mankind was making of the aquatic world. In 1855 the famous scientist Prof. Michael Farraday, writing in the Times, described the filth of the Thames, which had become a national humiliation. He called it a fermenting sewer, while Dickens noted that the mire and mud in the city was deep enough to believe that Creation had just begun. From this, he thought, it would “be wonderful to meet a Megalosaurus, forty feet long or so, waddling like an elephantine lizard up Holborn Hill” (Bleak House, 1853).

From Dickens’s time until today, the Thames is a marvel of successful clean-up, and proves that it is possible to redeem even an extremely polluted aquatic ecosystem and still maintain a growing human population. Though it required large sums of money and many years of constant dedication, and though storm events still bring inflows of untreated sewage, the Thames estuary has been transformed. It now supports normal fisheries, the passage of migratory salmon, and a massive yield of freshwater resources for public use.

From this we can see that there is hope for the Kafue River. With the help of sewage-treatment facilities and filter swamps of papyrus—with or without monster fauna—the Zambezi could survive.

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The delta of the Zambezi River for many years was cut off from public view because of a civil war that lasted 16 years and killed over 900,000 people. The area of the delta consists of a 5,800-square-mile region where the river divides into many branches with reed-fringed banks, sandbars, and permanent and seasonally flooded low-lying wetlands, including about a quarter of a million acres of papyrus swamps.

In addition to the effects of the war, the delta suffered from the impacts of two large dams built at Kariba and Cahora Bassa (Map 8, p. 213). It is today only about half as broad as it was before the construction of these dams. The Kariba Dam, built in the ’50s, required Operation Noah in 1960 to capture and rescue 6,000 large animals and numerous small ones threatened by the lake’s rising waters. Further downstream, the Cahora Bassa Dam was filled in 1974, after which time the dam trapped sediment and brought about a constant flow. This disrupted the natural cycle of wet-dry periods and resulted in a reduction in the size of the floodplain and a reduction in the number of channels in the delta, as well as a loss of local fisheries and depletion of birdlife.

The loss of sediment deposition in the delta resulted in coastal erosion, a 40% loss of mangroves, and a decline in prawn catch by 60% between 1978 and 1995. Some of these changes parallel those of the Nile Delta when the Aswan Dam was closed; the difference is that the water allowed through the Aswan Dam is used up in irrigation, so that only a small amount reaches the Nile Delta and this is not enough to stop salt water intrusion. In the Zambezi Delta, the water still flows as before but the flow is now a steady stream, except during heavy rain when the dams are in danger of overtopping. Floodgate releases during flood events are an enormous ongoing problem. Both of the dams on the Zambezi cause havoc to the residents and the animals and plants when water is released in quantity to the floodplain. For example, rising levels in Lake Kariba in March 2010 led to the opening of the floodgates, requiring the evacuation of 130,000 people and causing concerns that flooding might spread to nearby areas.

Though it has never been an important long-distance transport route, the lower Zambezi is deep enough to handle barges, and it is navigable from its mouth in the delta up to the Cahora Bassa Dam. Now with coal mining going forward in the central provinces by companies headquartered in Brazil and Australia, Mozambique expects to start producing over 20 million tons of coal per year in the next five years. The short-term transport solution by rail to the port of Beira on the coast south of the delta will be superseded by river transport, which makes it imperative that the Zambezi River be made navigable.7 An initial investment of $200 million will begin the process which will presumably widen and deepen the main channel. With that, the delta will change again.

There is already concern in the country about environment issues, and awareness growing of the long-term cost of impacts. Recently, the two parties who earlier waged the Civil War faced off in Parliament, but this time it was a fight over environmental matters, as the largest opposition party, the former rebel movement RENAMO, accused the government of “putting the lives of thousands of people at risk” by authorizing an aluminum smelter to release emissions without passing through filters while their fume-treatment facilities were being rebuilt.8

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The ecology of the delta was studied in 2001 by a team headed by Richard Beilfuss, Vice-President of the International Crane Foundation and Adjunct Professor at the University of Wisconsin and the Universidade Eduardo Mondlane in Mozambique. Beilfuss et al. noted that in an earlier study in 1910, “vast expanses of papyrus marsh” had been found and marked on maps as Mozambican “Sudd.” But they found little evidence of any papyrus in this area in aerial photos taken in 1960 at the time Lake Kariba was being filled. Today, after a subsequent reduction in delta swamps because of the dams, the papyrus swamps make up only about 200,000 acres.

It is obvious that in recent times the Zambezi River in Mozambique and the delta wetlands have had a respite; but how long that will last, no one knows. Thankfully, the water-quality problems that exist upstream in Zambia do not exist yet in the delta. In Lake Kariba, heavy metal accumulation in the sediments and pollution from sewage are evident; but downstream in Lake Cahora Bassa, the water quality still seems quite good.

As industry begins to grow in Mozambique, especially mining and smelting of aluminum, it is expected that the Zambezi below the Cahora Bassa Dam will begin to change and the wetlands of the delta will suffer, unless the lessons learned in the Copperbelt are applied here as well. The task ahead will be to draw up and implement a plan for the river and the delta, both of which are unusual and varied enough to be managed as tourist resources—much like the Okavango Swamp in Botswana, a swamp that brings in millions in foreign exchange while employing thousands of people, and is a place where papyrus thrives and helps keep the place vibrant and alive.