Pantanal
The Pantanal is considered by many to be the world’s largest, freshwater, wetland system. An immense alluvial plain, the Pantanal is situated along the northernmost part of the Paraguay River and its tributaries and becomes extensively flooded during the rainy season. It extends through millions of hectares of central-western Brazil, eastern Bolivia, and northeastern Paraguay in central South America.
The Pantanal is one of the most pristine and biologically rich environments on the planet. It also provides many economic benefits, including offering a huge area for water purification and groundwater discharge and recharge, climate stabilization, water supply, flood abatement, and an extensive, transport system, among numerous other important functions. However, despite its beauty and remarkable environmental and economic values, the Pantanal faces an uncertain future stemming from a myriad of socioeconomic pressures.
Estimates of its size range from 140,000 km2 (54,000 square miles) to 210,000 km2 (81,000 square miles), making it larger than many countries.
Location
The Pantanal is contained within the Upper Paraguay River Basin. Roughly one-third of the basin is the complex and vast low-altitude floodplain known as the Pantanal, and two-thirds is the Planalto, or highlands.
The Upper Paraguay River Basin is the upper sub-basin of the Paraguay Basin, which is part of the 2.8 million km2 Paraná Basin (or Paraná-Paraguay Basin). The Paraná basin in turn is a sub-basin of the Rio de la Plata basin (a region which also includes the Uruguay sub-basin, draining the Uruguay River, and the Salado sub-basin.)
The Paraguay River (in Portuguese, Rio Paraguai; in Spanish, Río Paraguay), the feature that gives the Paraguay Basin its name, begins in the northern part of the watershed and extends some 2,550 km southward to near Corrientes, Argentina, where it combines with the Paraná River. The headwaters of the Paraguay are located in a slightly pronounced rise, the Chapada dos Parécis, that divides the Paraguay sub-basin from the headwaters of some Amazon tributaries. Farther east, the Chapada dos Guimarães forms another physical barrier between the Amazon and Paraguay River Basins.
Major tributaries of the Paraguay River within the Pantanal include the Taquari River, Miranda River, Negro River and the Cuiabá River, as well as the São Lourenço River, which flows into the Cuiabá River, and the Aquidauana River, which flows into the Miranda. These are all left-bank (east) tributaries arising in Brazil. Bolivian and Paraguayan tributaries are notably smaller.
The Pantanal and Upper Paraguay River Basin extend into three nations. An estimated 80 percent of the Pantanal is located in central-western Brazil, in the two states of Mato Grosso and Mato Grosso do Sul. Another roughly 10-15 percent of the Pantanal extends into eastern Bolivia, and the remaining, smallest portion is located in eastern Paraguay. (In Bolivia and Paraguay, the Pantanal is generally referred to as "el Gran Pantanal" or "el Pantanal," while Brazilian sources often reference it as "Pantanal Matogrossense")
Size
Estimates of the size of the Pantanal vary widely.
Silva and Moura (1998), who delimited and quantified only the Brazilian Pantanal, places the size of the Pantanal in Brazil at 138,183 km2, and the area of the Upper Paraguay River Basin in Brazil at 361,666 km2. The Brazilian Pantanal is 38.2% of its associated basin in their study. Silva and Moura define the Brazilian Pantanal as all of the continuous area inside the Upper Paraguay River Basin subjected to periodic flooding, and localized between Fazenda Barra do Ixu in the north (above Cáceres) and the confluence of the Apa River with the Paraguay River to the south (below Porto Murtinho).
A Brazilian government investigation, which utilized mainly physiomorphological mapping and considered interactions between various physical and ecological elements, delimited establishes the Brazilian Pantanal at a similar surface area of 139,111 km2 (Brazil Ministério do Interior 1979).
However, an earlier, governmental investigation places the dimensions of the Brazilian Pantanal at 168,000 km2, the entire Pantanal of Brazil, Bolivia and Paraguay at 242,000 km2, and the entire basin of the three countries at 496,000 km2 (Brasil Ministério do Interior 1974).
One analysis that considered only factors related to soils established the Brazilian Pantanal at an intermediate area of 153,000 km2 (Amaral Filho 1986).
By any measure, this is an immense region. If one considered the entire Pantanal to be but 170,000 km2 (17 million hectares or 42 million acres) C, it would still encompass an area more extensive than many countries, including England, Austria, Hungary, Greece, or Ireland. It is larger than 29 of the states in the United States, surpassing New York, Wisconsin, and Florida. As a wetland system, it is likely unsurpassed. Indeed, using figures supplied by the World Conservation Monitoring Center, the Pantanal would comprise about 3 percent of the entire world's wetlands.
Character of the Pantanal region
The word “Pantanal” derives from the word pantano (pantano in Spanish, pântano in Portuguese), which generally translates as swamp, marsh, or bog. However, the Pantanal is more than one of these specialized wetland types. The term designates a river floodplain region and it encompasses a variety of ecological sub-regions. Within the Pantanal are large rivers, lakes and other standing water, terrestrial ecosystems, and diverse types of riverine, lacustrine, and palustrine "wetlands"—the transitional ecosystem between aquatic and terrestrial systems. Gottgens et al. (1998) described the Pantanal is an “immense floodplain mosaic” that includes “seasonally inundated grasslands, river corridors, gallery forests, lakes and dry forests.”
In essence, the Pantanal is an immense lowlands or alluvial depression that is located along the the Paraguay River and its tributaries, and that becomes extensively flooded during the rainy season. Whereas outside the Pantanal, there is a slope of about 1/2 to 1 meter drop in elevation for every kilometer traversed, within the Pantanal this gradient drops to only about 1-2 cm/km in the north-south direction and 6-12 cm/km in the east-west direction. This is a very slight slope, and when the extensive rains come during the wet season, the basin swells.
The Pantanal has two seasons: a wet season from roughly October to March, and a dry season from April to September. About 80% of the rain falls during the wet season. While the precipitation in the Upper Paraguay River Basin (annually about 800 to 1,600 mm—32-64 inches) is not substantially higher than in many other sections of Brazi, it is concentrated in this wet season. The largest average rainfall is the higher elevations.
In the more northern latitudes, the rainfall is particularly concentrated between the months of January and March, during which up to 50 percent of the annual rainfall occurs (Brasil Ministério do Meio Ambiente 1997). An average rainfall of 250 mm (10 inches) during January alone is typical in the northern part of the basin. This concentrated rainfall, combined with factors such as the very reduced topographic slope, poorly drained hydromorphic soils, reduced runoff bed and small exit area, results in a flooded plain, which propagates from north to south and from east to west along the Paraguay River C the Pantanal=s only natural drainage route. About 70-80 percent of the Pantanal area floods each wet season. Water levels may be as much as five meters higher than during the dry season (Junk and Silva 1995).
This remarkable variability between seasons gives the Pantanal its character and impacts the fauna in predictable ways. The general response of riverine fish to flooding is lateral movement over the floodplains, and the main feeding and growing time for the fish tends to take place during this highwater period (Lowe-McConnell 1987). The start of the flood season also corresponds to the period when most riverine fish species breed, allowing the young to be born when there is abundant food and cover. Floodwaters spreading over the plain are enriched by nutrients, leading to an explosive growth of aquatic vegetation and microorganisms and subsequently a marked increase in the number of larger invertebrates used as fish food.
The onset of the dry season provides another scenario. As the water retreats, it leaves dry land for animals to graze that were previously inundated. It likewise strands sizeable numbers of fish which failed to return to the larger channels. The drying pools of fish left by the subsiding water provides a feast for wading birds such as Jabiru storks, snowy egrets and roseate spoonbills. The fish losses from the strandings are considered to be enormous (Lowe-McConnell 1987). The Upper Paraguay River Basin is understood to be relatively new in geological time, created by (i) a wearing down of mountains on the Brazilian side (north, east and southeast) to form highlands of some 600-700 m above sea level, (ii) the creation of the Andes to the west, and (iii) the depression of the Pantanal area to form a virtual inland sea, which gradually filled with sediments. It is further speculated that this region was once connected to the ocean, accounting for the marine animal fossils buried in the shale and sandstone. The natural process of sedimentation gradually filled in the basin to an average height of about 100 meters above sea level. Sediments in the Pantanal are considered to be hundreds of meters thick.
With its variety of ecological landscapes, from terrestrial forests to seasonally inundated grasslands to perennial lakes, the Pantanal is a Acomplex of ecosystems.@ From area to area, it exhibits a wide diversity in terms of its community of organisms and the controlling environment. The Pantanal is thus commonly delineated into several distinct sub-regions, based on various ecological, geopolitical and physiomorphological aspects. Sanchez (1977) delineated 17 such sub-regions, Magalhães (1992) reported ten, and Silva et al. (1998) settled on 11 subregions. The Pantanal is also a dynamic system which can show substantial changes from year to year. This wide variety of ecological sub-regions, seasonal cycles and successional changes, combined with abundant water and high primary productivity, contribute to the Pantanal being one of the most remarkable and biologically diverse systems on the planet.
Human population
The Pantanal itself is sparsely populated. In particular, the Bolivian and Paraguayan sides have very low human densities; they are virtually uninhabited. The Brazilian side, while more populated, also has a relatively low population density estimated at 30,000 to 300,000 inhabitants (including native Indian populations), depending upon how one is specifically delineating the region and which population centers are included. As for the greater Upper Paraguay River Basin, the Brazilian government listed a 1990 population of 1,225,000 basin inhabitants in the state of Mato Grosso and a 1991 population of 448,458 in the state of Mato Grosso do Sul; this figure excludes the large capital city of Campo Grande located outside the basin (Brasil Ministério do Meio Ambiente 1997). A 1994 estimate placed the number of inhabitants in the basin of Mato Grosso do Sul at 465,400 people. This density is quite low. For the state of Mato Grosso do Sul, for example, the number of people within the basin averages 2.2 inhabitants/km2, or about one individual per 160 hectares. This compares to an average of 17.3 inhabitants/km2 for Brazil itself. The Brazilian government projects that by 2025 the population will reach 2.8 million basin inhabitants in Mato Grosso and 650,000 in Mato Grosso do Sul B a more than 100 percent overall population increase in the basin area since 1990-1991.
Economically, the main activities in the Pantanal area are cattle ranching, agriculture (rice, soy beans, corn, sugar cane, etc.), agroindustries, mining (gold, diamonds, iron, manganese), professional fishing, and tourism B the latter more sportfishing than ecotourism. The highlands around the Pantanal have experienced accelerated growth in recent years, particularly in metropolitan centers such as Cuiabá, the capital of Mato Grosso. In terms of political divisions, Silva and Moura (1998) report 64.64 percent of the Brazilian Pantanal is located in the state of Mato Grosso do Sul (MS) and 35.36 percent in the state of Mato Grosso (MT). According to their study, four counties or districts (municípios) account for almost three-quarters of the Brazilian Pantanal area: Corumbá, Poconé, Cáceres and Aquidauana. Those counties with the greatest percentage of their area designated as being within the Pantanal are Barão de Melgaço (99.2 percent), Corumbá (95.6) and Poconé (80.3), and with the least overlap with the Pantanal found in Bodoquena (1.8) and Lambari D=Oeste (15.9).
Plant and animal life
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The Pantanal is one of the world’s great reservoirs of plant and animal life. This floodplain wetland system is highly productive, supporting both a large number of species and an abundantly high concentration of these species. It has been said that the Pantanal has the highest concentration of fauna in the New World, comparable to the densest animal populations in Africa (Magnanini et al. 1985; Pádua 1991).
Bird species are particularly diverse. The region is an important migratory bird stopover point and wintering ground, used by birds from three major migratory flyways C bringing ospreys from the Nearctic latitudes to the north, woodstorks from the Argentine pampas to the south and flycatchers from the Andes to the west (Eckstrom 1996). The result is one of the planet=s most diverse avian communities. According to the 1997 PCBAP report, 656 species of birds, belonging to 66 families, have been identified in the Upper Paraguay River Basin (Brasil Ministério do Meio Ambiente 1997). This includes such North American migratory birds as the Upland Sandpiper (Bartramia longicauda), the American Golden Plover (Pluvialis dominica) and the Black-necked Stilt (Himantopus himantopus).
The Pantanal=s ichthyofauna is likewise quite diverse, although far below the Amazon region. A recent publication by Britski et al. (1999) identifies 263 species of fish in the Pantanal itself, including 109 species of Characiformes, and 105 Siluriformes. The study covers all of the Pantanal proper, including the Paraguayan and Bolivian portions; it does not include headwater areas of the rivers draining into the Pantanal that are poorly known and likely harbor a high number of species.
TCommon figures cited for other fauna identified in the Upper Paraguay River Basin are 95 species of mammals and 162 species of reptiles (Brasil Ministério do Meio Ambiente 1997), although many of those species occur in the highlands outside of the Pantanal. Forty-six mammal species are considered rare or in danger of extinction. Amphibians have been only partially identified, with 40 species recognized as of 1997 (Brasil Ministério do Meio Ambiente 1997).
Not a lot of faith should be placed in any of these numbers. Along with the Amazon, the Pantanal is a mother load of unrecorded life. The discovery of new vertebrate species, and the sighting of known species previously unrecorded in the Pantanal, is not an infrequent occurrence. In particular, vast sections of the Bolivian and Paraguay Pantanal are poorly researched. The invertebrate and plant diversity is likewise remarkable but overall inadequately assessed.
Pott and Pott (1997) collected over 1,700 flowering plants during a ten-year period C not counting aquatic plants, sedges or grasses C and presented 500 in their book, Plants of the Pantanal. Overall, this immense and not easily accessible region is poorly known.
More than diversity, the Pantanal is particularly renowned for its concentration of animals, which makes it a visual paradise for naturalists, photographers and ecotourists. The wildlife density is considered to be the greatest in the neotropics.
Caimans are particularly abundant. Eckstrom (1996) reports a figure of 10 million caimans in the Pantanal C the Ahighest concentration of crocodilians in the world.@ The 1997 PCBAP report estimated a 1993 average Avisible@ density of 7.4 individuals/km2 of the common species, Caiman crocodilus yacare, an estimate that likely undercounts by millions the adult caimans, given the problems of visibility (Brasil Ministério do Meio Ambiente 1997). In the 1970s and 1980s, an estimated one million skins a year were illegally poached. The population of capybaras (Hydrochoerus hydrochaeris) is estimated to approach a half-million in the Brazilian Pantanal. The Pantanal continues to be one of the best places to see jaguars (Panthera onca), giant river otters (Pteronura brasiliensis), giant anteaters (Myrmecophaga tridactyla), giant armadillos (Priodontes giganteus), the endangered maned wolves (Chrysocyon brachyurus) and marsh deer (Blastocerus dichotomus) C each of which is considered to be the largest of its kind in South America (Eckstrom 1996). Hunting is proscribed throughout the Brazilian portion of the Upper Paraguay River Basin, as it is throughout most of Brazil.
There have been 15 species of parrots identified in the Pantanal, including the blue and yellow macaw (Ara ararauna), blue-fronted amazon (Amazona aestiva), green winged macaw (Ara chloroptera), and red-shouldered macaw (Ara nobilis). The Pantanal remains one of the best environments to see the endangered hyacinthine macaw (Anodorhynchus hyacinthinus), the largest member of the parrot family. Various reports put the scarlet macaw (Ara macao) in the state of Mato Grosso (Magalhães 1992) but not within the Pantanal (Pittman 1999).
Other species commonly encountered in the Pantanal include the anaconda (Eunectes murinus), howler monkey (Allouatta caraya), Capuchin monkey (Cebus apella), coati (Nasua nasua), ocelot (Felis pardalis), cougar (Felis concolor), tapir (Tapirus terrestris), anhinga (Anhinga anhinga), great egret (Casmerodius albus), snowy egret (Egretta thula), roseate spoonbill (Ajaia ajaja) and what is often referred to as the symbol of the Pantanal, the jaburu stork (Jabiru mycteria).
Value of the Pantanal
It is becoming increasingly appreciated that wetlands in general are among the world=s most productive environments and provide innumerable economic, ecological, cultural, recreational and aesthetic values. As a wetland of exceptional size, the Pantanal embodies many of the aforementioned values in a big way. It has one of the most impressive freshwater fisheries on the earth, serving an exceptional biogenetic reservoir. It not only provides an extensive water supply and transport system for its inhabitants, but it serves to remove sediments and pollutants, thus improving the water quality for millions of people downstream. The reduced water velocity in the Pantanal, and its storage of water, create excellent circumstances for mineral uptake by plants, microbial processing and the settlement of sediments and chemicals such as heavy metals, which are sorbed to sediments (Gottgens 1998). Flood control is another major value of the Pantanal. The Pantanal has a regulatory effect on the Rio Paraguay, extensively reducing and delaying the height of the flood peak and thus reducing the flood risk downstream. Because of the Pantanal, the flood peak of the Paraguay is as much as two to three months later than the Paraná into which it empties, avoiding the cumulative impact of these two flood peaks combining downstream. But there are also values that are less quantifiable and whose conversion to dollars and cents is beyond current means. This is the aesthetic and peace-of-mind attribute of being in such an ecological paradise. It is the element of experiencing beauty, and the near mystical experience and clarity of mind that comes with being immersed in a natural wonder like the Pantanal. Despite these many values, the historical view of wetlands was that they were wastelands. Such a perspective found value in draining, diking and otherwise modifying them in order that the lands serve intensive agricultural, residential or industrial uses. Some wetlands were lost via mining, waste disposal, pollution or redirecting the water for more valued purposes. Thus, we have arrived at a situation today where an estimated 50 percent of the world=s original wetlands have been lost, and 54 percent (87 million hectares) of original wetlands in the United States. France, Germany, Italy and Spain have reported losses from 57-66 percent in this century (Barbier et al. 1997).
The Pantanal wetland faces the same threat. This region is on the verge of major developmental changes. An expanding infrastructure, growth in population, expansion of industry and farming are all part of the changing reality of the Pantanal and the surrounding highlands at the turn of the millennium. Between major hydrological projects and the everyday encroachments of developers= less desirable accompaniments, the Pantanal region bears ominous signs. In recent years, we have started to recognize that wetlands are treasures, and integral to the quality of our world=s ecologies and economies. The question is how to apply the lessons learned to the Pantanal wetland. In light of all that is taking place globally, one recognizes a serious need to identify the challenges to the Pantanal and to be proactive in approaching its management.
Threats to the Pantanal=s future
What are some of the current challenges facing the Pantanal? The Pantanal is often referred to as pristine and intact C as characterized earlier in this paper. It is true that the interior of the Pantanal is relatively untouched when compared to many other systems. Population and infrastructure remain low in its more remote regions. But if we consider the watershed itself, there are serious problems, and we cannot discuss the Pantanal independent of the highlands around it. There are also serious problems escalating inside of the Pantanal itself. Water Pollution. One increasingly serious concern is water contamination, including mining byproducts, agrochemicals, sewage and garbage. A common problem relative to mining operations is mercury contamination from gold mining operations. This is particularly significant in the state of Mato Grosso. Mercury is used to concentrate placer gold, often at concentrations approaching three grams of mercury for every gram of gold mined (Banks 1991). Brazil passed a law prohibiting the use of mercury in gold mining in December of 1988; nevertheless, mercury use and contamination remains a troubling factor as enforcement of the law confronts the reality of many hundreds of digs spread over vast and often isolated areas. High levels of mercury have been found in fish and in fish-eating birds, such as kingfishers and raptors. Agochemicals, including the heavy use of fertilizers, herbicides and pesticides in agricultural activities, pose another difficult problem as they are washed into the streams and rivers. Alho and Vieira (1997) note that pesticides, including toxins such as disulfan, endosulfan and thiodan, are Afreely used and sold.@ In many cases, the poor quality of the soil has led farmers to compensate with large amounts of agrochemicals.
Both untreated, domestic sewage and garbage are likewise discharged into the Pantanal=s rivers and wetlands, adding to the organic loading and sediment and chemical contamination. Much of this comes from rapidly-growing domestic centers in the highlands outside of the Pantanal, and particularly in the northern Pantanal. One infamous case of this type is Cuiabá, the capital of Mato Grosso. Cuiabá is located in the watershed of the Cuiabá River and lacks waste treatment facilities. The domestic waste from this major metropolitan area is discharged into the Cuiabá River, one of the major tributaries of the Paraguay River. Overall, the over two-million inhabitants of the Upper Paraguay River Basin contribute millions of gallons everyday of untreated wastewater to the Pantanal, and this situation will become increasingly serious as the population of the basin is projected to double by 2025. The inhabitants of the Upper Paraguay River Basin are fortunate to be living in and around such an enormous wetland, one with a remarkable capacity to cleanse much of the natural and man-made organic waste, chemical contaminants and sediments that flow into it. Although this wetland serves as a natural sewage-treatment plant in this respect, the extent to which the Pantanal can process contamination is not well known and the rapidly increasing population in the watershed heightens the gravity of the situation. Loss of biodiversity. Another concern is loss of biodiversity. At least 50 species are reported to be threatened or endangered in the Brazilian Pantanal. Such large predators and herbivores as the giant river otter, maned wolf, ocelot, cougar, jaguar, giant anteater, marsh deer and giant armadillo used to be found in large numbers in the Pantanal. Today, these are all listed as endangered or threatened with extinction. The main sources of pressure on biodiversity appear to be anthropogenic effects: habitat destruction, poaching, over-fishing, and the business of capturing threatened and endangered species for export or for the Brazilian pet trade. Although big-game hunting is illegal in the Brazilian Pantanal and has been since 1967, considerable poaching remains. It has been slowed but is still significant for big mammals like the jaguar. The hyacinthine macaw, blue and yellow macaw, red and green macaw (or greenwing macaw), blue-fronted parrot, and toco toucan (Ramphastos toco) are captured for resale as pets, part of a $5 billion (US) global business of illegal animal trafficking [figures quoted are in US dollars]. The appeal to animal traffickers is obvious: A single hyacinthine macaw can fetch $6,500 to $12,000 in the United States, and the Pantanal remains one of few hyacinthine macaw strongholds. In February of 1999, authorities interdicted an effort to smuggle 24 hyacinthine macaw eggs from Sao Paulo to Pennsylvania, with the value of the eggs estimated at $10,000 each. Likewise, a red and green macaw can fetch between $1,300-$1,800, and a blue and yellow macaw can bring $900-$1,400. In recent years, there has been an increase in Brazilian governmental efforts to stop animal traffickers. Nonetheless, the remote Pantanal environment, and the ease of crossing over the border to Paraguay and Bolivia, present a difficult problem for law enforcement. Confounding the problem is the view of many people that proscriptions against trafficking are foolish or an unfair meddling in an individual=s need to survive. There is also substantial over-fishing taking place. As with hunting and capturing of animals, there are a number of laws on the books to regulate fishing. However, enforcement is often inadequate. If you remain in a remote area long enough, you can observe open violations of the rules, in terms of fishing equipment used, species taken, numbers caught and seasons fished. Often a specific species making a migratory run is heavily over-exploited. All of which results in acute or chronic ecosystem disruption and loss of biodiversity.
Erosion and Sedimentation. Another serious challenge for the Pantanal is the evident increase in erosion and sedimentation. Human activities accelerating this natural process include clearing the land for agriculture, the opening of new roads, logging, extensive burning, and so forth. A lot of these problems are in the watershed and naturally effect the floodplain.
Fires of human origin are particularly prevalent in the Brazilian Pantanal and highlands during September-October, and are used by ranchers to clear old pasturage in order bring up tender, green shoots for their cattle or as an easy (and snake-free) means of clearing the land for agriculture. While natural fires have an environmental role, as they have in the Everglades, the extent of human-induced burning is quite remarkable and highly destructive. Well-known conservationist Adalberto Eberhard, founder of Ecotrópica, has remarked that the Brazilian state of Mato Grosso Ais the champion of burning.@
In recent years, agricultural development in the Brazilian highlands has been increasing substantially, leading to an accelerated clearing of the land. This deforestation has led to increased erosion and sedimentation of the Pantanal waterways, which in turn increases flood risk, lowers biodiversity and disrupts the overall sediment budgets of the catchment basin. As with other problems in this remote region, there are a number of good federal and state laws to limit land clearing and control erosion, but enforcement lags. For example, laws prohibit landowners from clearing forests all the way to the riverbank, but the restrictions are often ignored.
The Taquari River highlights the seriousness of the threat posed by erosion and sedimentation. The Taquari River is one of the major tributaries of the Paraguay River and was once highly respected for its commercial and sportfishing. Within the past 10 years, there has been an exponential increase in sedimentation, mainly resulting from erosion in the highlands. This has resulted in substantial alteration of the channel, including the perpetual flooding and loss of over 100 farms, and at one point the 70% of the river branches off, reducing the channel to only 30% of its former size. The fishing industry is now virtually non-existent in this river.
In Bolivia and Paraguay there is still a low density of people and low impact, and those areas remain quite well-preserved. However, the increasing population in the Brazilian highlands and in the Pantanal C and particularly during the last few decades in Mato Grosso C has resulted in increased problems of sedimentation and erosion.
Modifications of natural cycles. Another challenge in the Pantanal region is modification of the natural hydrology through construction of local dams and dikes. (Major hydrological projects will be discussed in the next section.) The construction of dikes by landowners serves to keep water out of their property and thus enhances agricultural use of the rich alluvial soils for crops and dry land for grazing. However, it also effects new water-flow patters and increases flooding outside of these abuts. Furthermore, the dry lands protected from seasonal flooding through these constructions gradually decline in fertility due to the absence of the natural nutrient-replenishing system provided by the floods (Sparks 1995). This leads to an increased need for commercial fertilizers. The damming of streams similarly alters water-flow patterns, effects sediment budgets and disrupts the natural balance between wet and dry seasons.
Major anthropogenic impacts on the Pantanal
Four major challenges confronting the Pantanal have been summarized above. If we look at them in terms of human action, we could list seven anthropogenic actions which are particularly deleterious: (1) burning and other deforestations of the watershed, (2) exploitation of fauna by poaching and overfishing, (3) discharge of untreated, urban waste, particularly in the state of Mato Grosso, (4) contamination from agrochemicals, (5) discharge of chemical pollutants, such as mercury through mining operations, (6) poorly planned road construction, and (7) local dam and dike construction.
The Paraguay-Paraná Waterway Project or AHidrovia.@ In recent years, a major preoccupation for those desiring a healthy Pantanal has been the proposed Paraguay-Paraná Waterway or AHidrovia@ (sometimes referenced in English as AHydrovia@). It is a controversial idea that has gained a lot of press in recent years.
The Hidrovia project is an intergovernmental plan, originated by the La Plata Basin countries (Argentina, Bolivia, Brazil, Paraguay and Uruguay) in the late1980s, that proposed opening up over 3,442 km of the Paraguay and Paraná rivers for good navigation of barge convoys. A keystone of the project was to create year-round navigational transport of cargo from landlocked regions in the northernmost navigable portion of the Paraguay River at Cáceres, Brazil to Nueva Palmira, Uruguay on the Rio de la Plata estuary, connecting to the Atlantic Ocean. The Hidrovia project would also serve to promote regional integration. The five governments involved created the Intergovernmental Committee on the Hidrovia (CIH) to promote and oversee the project.
Original proposals called for straightening, widening and deepening the meandering upper stretches of the Paraguay River, in order that it might become navigable for vessels up to 2.8 meters draft during low-water periods. Proponents envisioned substantial dredging of the Paraguay River, removal of flow-impeding rock outcrops, channel straightening, and dike and dam construction to control the widespread flooding.
Clearly, the potential long-term economic benefits for the regions concerned were considerable. The project would lower costs for transporting downstream items such as soy beans, oil, corn, cotton, manganese and iron ore. Instead of $60-$90 a ton for truck hauling, river transport would cut the costs to perhaps half of that, from $30-$50 a ton, combined with expected lower costs for river upkeep than road maintenance (Margolis 1995). There also would be benefits in terms of providing landlocked countries with year-round ports, opening areas for expansion, indefinite work for waterway construction and maintenance companies, and the overall economic integration of the region. Based on these concepts, CIH originally saw good prospects for the project, and in 1990 Internave, a Brazilian engineering firm, provided a positive economic feasibility study which essentially called for a Ageological facelift of the region@ (Margolis 1995, Gottgens 1998 ). However, the costs of the project were likewise considerable, particularly when one added in the environmental impact. One could expect increased flooding, water contamination, erosion, disruption of natural communities and interruption of natural cycles. Importantly, flooding could be anticipated to worsen downstream, as the two-to-three-months delay between the Paraguay River=s flood peak and the Paraná River=s flood peak could be expected to narrow. Water quality for the millions of people downstream would likely be impacted. Fisheries were also expected to be damaged. Such a large-scale modification of the Paraguay River could be anticipated to have a serious environmental impact on the Pantanal. It was envisioned that large sections would be drained as water-flow velocity increased down the Paraguay River. Fauna dependent on aquatic environments would lose critical refuges, and the normal regime of flood pulses into the floodplain, so essential for sustaining diversity and productivity, would be disrupted. Farmlands would not be revitalized by the flood waters, and serious losses of wetlands could be expected. Ponce (1995) concluded that blasting rocky sills as a means of deepening the navigation channel would be the most serious intervention, irreversibly impacting the hydrology of the Upper Paraguay River and likely changing the Pantanal forever.
The original plan of channel straightening, dredging, damming and rock removal meet justifiable opposition on economic and environmental levels. Additional studies and assessments were conducted by various non-governmental, governmental and inter-governmental bodies that took into greater account the environmental costs, in addition to the engineering and economic feasibility. Between 1995 -1997, the CIH also conducted a more thorough economic, engineering and environmental impact assessment, supported by millions of dollars worth of technical assistance from the Inter-American Development Bank and the United Nations Development Program. While this later analysis proved to be a vast improvement from the faulty and limited Internave report, it likewise came under strong criticism from reviewers as incomplete and inadequate (Gottgens 1998). All in all, the Hidrovia project generated considerable turmoil as competing political, environmental and economic factions staked out their claims. Over 100 national and international organizations expressed concern over the impact of this project, principally its consequences for the Pantanal.
The Hidrovia project, as originally proposed, is no longer seen as viable. However, this does not mean that hydrological projects on the Paraguay River and its tributaries will not occur piecemeal and still impact the Pantanal in a major way. Although governmental support for the Hidrovia itself has waned, principally among the Brazilian government, various smaller hydrological initiatives remain of interest. These proposed and actual structural interventions include various actions of dredging and channel straightening of the Paraguay River and its tributaries, some in the Upper Paraguay River Basin and others further south, where their hydrological impact could still affect the upper stretches and thus the Pantanal. Gottgens et al. (1998) note that smaller initiatives can lead to a Atyranny of small decisions,@ whose cumulative negative impact can actually be worse than a larger, more comprehensively planned project. Furthermore, various interests continue to advocate a commercial waterway into the heart of the continent, even if implemented piecemeal. Thus the Hidrovia project, or its various formulations, remains a vital concern to the Pantanal.
Lack of protected areas in the Pantanal
A contributing risk factor in the Brazilian Pantanal is the fact that there is very little formally protected area. In the Brazilian state of Mato Grosso do Sul, where most of the Brazilian Pantanal is located, not a single federal or state park exists. In the northern state of Mato Grosso, there is one relatively small national park, Parque Nacional do Pantanal Mato-grossense (Pantanal National Park), which has about 135,000 hectares. There is also the Taiamã Ecological Station, consisting of about 11,000 hectares. These remain the only official government-protected areas in the entire Brazilian Pantanal. Brazil=s Parque Nacional do Pantanal Matogrossense was established by federal decree in September of 1981, when it was converted from the smaller, former Cará-cará Biological Preserve. It is located at 17o 39'S 57o 25W in the western part of Mato Grosso on the border with Bolivia, and in the county (município) of Pocone. In May of 1993, Pantanal National Park was designated by Brazil for inclusion on the Ramsar list of Wetlands of International Importance. Notably, in 1995, the Nature Conservancy, in cooperation with the Brazilian conservation organization Ecotrópica, purchased two ecologically significant properties C the 26,718 hectare Dorache Ranch on the northeast border of Pantanal National Park, and the 13,665 hectare Acurizal Ranch on the southwest border C in order to expand the size and diversity of protective habitat around this preserve. Ecotrópica likewise holds title on the 13,409 hectare Penha Ranch on the Pantanal National Park=s southern border adjacent to the Acurizal Ranch. In 1997, these 53,000 hectares were officially designated Private Reserves of National Heritage C RPPN, AReserva Particular do Patrimônio Natural@ C by IBAMA, substantially increasing the preserved areas of the Pantanal.
In addition to Ecotrópica=s three properties, as of January 1998, seven other properties were officially in RPPN status, totaling around 77,500 hectares. This brings the total preserved areas in Brazil C national, state and private C to about 2 percent of the Brazilian Pantanal. Ninety-eight percent of the Brazilian Pantanal is privately owned.
The Bolivian Pantanal has considerably more protected area. Montaño (1999) affirms that 90 percent or more of the Bolivian Pantanal has some degree of legal protection, and substantial portions are inside of two recently created federally protected areas. The first is the Otuquis Pantanal National Park C Parque Nacional Pantanal de Otuquis C and contiguous Otuquis Natural Area of Integrated Management C ANMI Qtuquis: Área Natural de Manejo Integrado Otuquis C which occupies 1,005,950 hectares total (903,350 hectares and 102,600 hectares, respectively). The second is the San Matías Natural Area of Integrated Management C ANMI San Matías: Área Natural de Manejo Integrado San Matías C which totals 2,918,500 hectares. These two protected zones, established in 1997, were designed not only to safeguard the Pantanal but also the greater basin, including a variety of other environments such as subhumid Chaco forests, dry forests, and so forth. It is estimated that the surface area actually occupied by the Pantanal corresponds to about 12 percent of the San Matías protected area and 24 percent of the Otuquis protected area (Montaño 1999). Furthermore, the San Matías Natural Area of Integrated Management lies proximate to Pantanal National Park of Brazil, thus permitting the establishment of an extensive tract that will aid preservation efforts.
Initiatives for the future of the Pantanal
There are several avenues being pursued of potential importance for the future of the Pantanal. Ecotourism. Ecotourism is often presented as the best, long-term hope for the Pantanal, bringing in tourist dollars to the local communities and thus creating an economic incentive for these communities to preserve the environment. Generally, ecotourism is considered tourism to relatively intact natural areas, which has low impact on the environment, promotes conservation and provides a beneficial socioeconomic return to the local populations. With tourism being one of the world=s largest businesses, ecotourism indeed would seem to offer a profitable, long-range financial medium which could be more lucrative than other, more environmentally deleterious economic activities. For these reasons, the governments of Brazil, Bolivia and Paraguay are seeking to stimulate interest in ecotourism in the Pantanal, and organizations such as Conservation International and the WorldWide Fund for Nature (WWF), formerly the World Wildlife Fund, are likewise developing initiatives. However, several obstacles remain to ecotourism=s viability. In the Pantanal, there is a serious lack of infrastructure, such as accommodations and transportation. There is a lack of tourist information and trained guides are few. Furthermore, the region remains poorly-known in many nations, including the United States.
As a result of these and other factors, there is relatively little ecotourism in the Pantanal region. In particular, the Bolivian Pantanal is practically inaccessible and ecotourism is undeveloped, due to lack of tourist facilities and a transport infrastructure (Herrera 1995). The Brazilian portion of the Pantanal is somewhat better situated and is visited by hundreds of biologists and thousands of tourists a year. However, much of the Brazilian tourism is centered on fishing. There is also some nature tourism and what might also be called Aecolite@ tourism, involving tourists from Brazil and from countries such as Germany and Japan. But genuine ecotourism, where money is pumped back into the local community or environmental activities, is limited. These pseudo-ecotourism packages, rather than aiding the Pantanal, can actually have an adverse effect by disturbing the natural areas, increasing illegal activities, and heightening demand for facilities, infrastructure and luxury items. Cattle Raising. One of the chief economic activities in the Pantanal is cattle ranching. This enterprise is perhaps unique in that it is a widespread economic activity which impacts the landscape, although many authorities do not see raising cattle as a big environmental problem. Instead, it is generally presented as a long-term activity which developed in harmony with the environment or which at least poses minimal negative impacts. One reason offered for such a view is that the Pantanal has many, natural grassland areas that do not require the type of deforestation one might find in the Amazon, and also because cattle are often allowed free to graze on unaltered land. Furthermore, extensive flooding during the wet season can limit the amount of cattle raised on a piece of land to the pasturage available when much of the land is submerged. For these reasons, cattle raising is often promoted as a viable economic activity for the future of the Pantanal. Nevertheless, cattle ranching is not without its problems and detractors who see it as a problem. One can observe burning of wild landscapes in order to clear land for cattle or to bring up fresh shoots. Native plant life may be selected against, and the moving of cattle to new pastures can result in widespread loss of native vegetation. There are concerns regarding the effect of cattle grazing on soil erosion and sedimentation and the loss of wildlife refuge for native populations. The impact of cattle grazing on the Pantanal is hotly debated and needs further research. National Initiatives. Among the three key national stakeholders in the Pantanal, Brazil and Bolivia have been particularly active in advancing initiatives directed at management of the Pantanal. Bolivia has been the most active nation in terms of creating national reserves, having established the extensive Pantanal National Park of Otuquis, the adjacent Otuquis Natural Area of Integrated Management and the San Matías Natural Area of Integrated Management. In Brazil, there is a hopeful development as far as management of the Pantanal is concerned with the formation of the Upper Paraguay-Pantanal River Basin Committee C Comitê de Integração da Bacia Hidrográfica do Alto Paraguai Pantanal (CIBHAPP). This committee includes representatives of federal and state governmental bodies, the private sector and NGOs. It was constituted to handle inquires relative to the basin, coordinate technical and scientific studies, serve as a forum for debate and discussion and assist in the coordination of various programs underway in the Pantanal region. CIBHAPP is supported and implemented by the Brazilian Ministry of the Environment and the governments of the states of Mato Grosso and Mato Grosso do Sul. Thus, the Brazilian side has created an institutional mechanism to begin to manage the Upper Paraguay River Basin.
Another Brazilian coordinating mechanism for the Pantanal has been what is called the Pantanal Project-National Environmental Program C Projeto Pantanal-Programa Nacional do Meio Ambiente (PNMA). The first National Environment Program began in 1990, was reformulated in 1994 and completed operations at the end of 1998. A second National Environment Program is now under preparation. One component of these NEP programs deals with the Pantanal in Brazil, which had been specifically mentioned as a National Patrimony in the 1998 Federal Constitution. The purpose of the NEP Pantanal Project has been the management of several million dollars to protect the Pantanal ecosystem; coordinate state environmental agencies in the implementation of sub-projects such as faunal and flora studies and control of mining operations; rehabilitation of impacted areas; and elaboration of the Upper Paraguay Basin Conservation Plan, involving professionals from several institutions and universities, governmental organizations, and so forth. The Upper Paraguay River Basin Conservation Plan (Plano de Conservação da Bacia do Alto Paraguai or PCBAP) provided a comprehensive analysis of the Pantanal and Upper Paraguay River Basin and indirectly led to the aforementioned creation of CIBHAPP.
Conclusion (discussion area)
What will the 21st century hold for the Pantanal? In the 20th century, we witnessed dramatic changes in our world=s resources of wetlands and in our aquatic landscape in general. One can only wonder whether this new century will see the Pantanal continuing with this trend, and whether we will be asking, as we have for so many other ecosystems, AWhat went wrong with the Pantanal?@ Will we be reading newspaper articles titled, AIs it too late for the Pantanal@ or holding symposium on themes such as, ACan the Pantanal be Saved?@ or AIs it too late for the Pantanal?
At this point, the Pantanal is a vibrant, amazing natural treasure. It clearly can have a bright future. However, a bright future will require proper science and good management. The Atlantic Forest once stretched for 5,000 km along the coast of Brazil. It now extends to less than four percent of its original size, but it has taken the better part of 500 years of steady exploitation to cause this type of decline. The Everglades declined in less than a century. The Pantanal, arguably the largest wetland in the world, could well succumb in less than 30 years. We have the somber responsibility to determine what we can do to ensure the best possible future for this ecological paradise for subsequent generations.
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