Blue Action Paper: Interventions in the Paraguay River to increase heavy-vessel navigation (Hidrovia Paraná-Paraguay) would cause irreversible damage to the Pantanal, the largest wetland in the world

Matthias Wantzen and see full list of coauthors below

heavy vessel
Source: O Pantaneiro

Overview of the Hidrovia and the Paraguay River

The Hidrovia Paraguay-Paraná (HPP) is a project to improve navigability and infrastructure and thereby facilitate year-round transportation of commodities on barge trains between the upper reach of the Paraguay River at Cáceres (Brazil) through the Paraná River to the Rio de la Plata in Uruguay and Argentina (Sousa Junior et al. 2019). The main purpose of extending the Hidrovia up the Paraguay River is to transport soybeans and other agricultural commodities produced in Brazil, Paraguay, and Bolivia southwards to sea ports in Argentina and Uruguay for export to North America, Europe, and Asia. The first version of the project had been planned in the 1980s, but after evidence provided by scientists as well as societal concerns about the irreversible, systemic impacts on the Pantanal wetland in particular (e.g., Ponce 1995, Lourival et al. 1999, Hamilton 1999), the Brazilian part of the project was officially turned down in 2000 (Taques et al. 2020).1 Nevertheless, advocates for river transportation have continued to push for increased channel dredging as well as development of ports and other infrastructure along the upper Paraguay River. The process of decision-making regarding the Hidrovia has been regarded as a show-piece for the tragedy of the commons and the tyranny of small decisions (Gottgens et al. 2001, Tortato et al. 2022).

Recently (2022–23), preliminary licenses were issued for construction of port facilities upriver of the Pantanal near Cáceres (MT) and downriver of the Pantanal at Porto Esperança (MS). The establishment of this infrastructure is a first step towards the transformation of the largely natural section of the Paraguay River within the Pantanal into an engineered waterway to support barge transport. The Hidrovia is currently envisioned to make the Paraguay River through the Pantanal navigable year round for larger barge tows (multiple barges lashed together and pushed by a towboat), which would require dredging and straightening of meanders. The goal is to be able to transport up to 1 billion tons of soybeans per year in tows of 2x3 barges, each measuring 140 m long, 24 m wide, and 1.8 m deep (EVTEA 2015). Previous designs also included removal of rock outcrops from the river bed in numerous locations.

The unlicensed use of the river for barge transport since the 1990s has already shown evidence of the severity of potential environmental and cultural damage in and along the river corridor (Wantzen et al. 1999, Gottgens et al. 2001). The main argument in favor of the Hidrovia is that agricultural commodity transport by navigation would reduce costs and time compared to the current truck transport. That assertion, however, does not consider the costs for the Pantanal in terms of the negative environmental and social impacts that have already become evident.

The Pantanal Wetland is considered National Heritage by Brazilian Constitution (1988), stating that “the use will be made, in accordance with the law, under conditions that ensure the preservation of the environment, including the use of natural resources”. The Pantanal is also considered by UNESCO as a World Natural Heritage (Conservation Area – 188,000 ha) and in a bigger area (264,176 km²) as Biosphere Reserve (UNESCO 2000). It includes six Ramsar Sites, (Ramsar Convention on Wetlands of International Importance), two of which being localized in the direct area of influence of the navigation in the North Stretch of Paraguay River (fig. 1).

The Paraguay-Paraná Hidrovia (HPP). The lower right-hand side insert shows the HPP (black line) and the Paraná River Basin (shaded area) in South America. The rectangle at the northern tip of the insert is the Upper Paraguay basin (Modified from Baigún and Minotti (2021)). The main map shows the planned northern reach of the HPP (The Paraguay River) within the Upper Paraguay basin and the Pantanal (Modified from Wantzen et al. (2023)). The Pantanal main tributaries and 21 critical reaches (i.e. sites which would have to be maintained by frequent dredging) are also displayed. Note that these critical reaches coincide with the most pristine river sections and the conservation areas of the Pantanal.

The Pantanal is the world’s largest contiguous freshwater wetland and its existence depends on seasonal flooding by the waters of the Paraguay River and its tributaries. The inundation of the floodplains is controlled by hardened sediment structures and rocky outcrops in the river channel that limit its capacity to drain flood waters during the wet season. Seasonal inundation in turn determines the ecological functions, ecosystem services, and the biocultural diversity of the Pantanal. However, to improve navigability in the river system, the channel structures that limit drainage are considered as obstacles that should be removed. Increasing the capacity of the river channel to drain floodwaters would reduce the extent and duration of seasonal inundation in the Pantanal. Thus, the Hidrovia puts the entire Pantanal socioecosystem at risk by – metaphorically speaking – “pulling the cork out of the bottle”.

Moreover, advocates of the Hidrovia ignore the option that commodity transport could be accommodated by the partially existing railway system if adequate improvements were implemented. Advocates also fail to note that during drier periods, barge transport often becomes impossible—and river levels have more often dropped below critical minima in recent years. During the low water seasons of 2019 to 2022, barge transport of soybeans and minerals in the Paraguay River downriver of Corumbá was interrupted by low water levels, even though that reach is naturally wider and had already been deepened by many years of dredging.

Thirteen reasons why the Hidrovia project should not be implemented in the Paraguay River along the Pantanal wetland

This white paper highlights the most relevant arguments for why the Hidrovia should not be implemented, specifically in the section of the Paraguay River known as “Tramo Norte” (i.e., between Cáceres and Corumbá), which runs through the most sensitive parts of the Pantanal wetland. The information presented here is based on the expertise of the authors and extensive reviews on the Pantanal (Tomas et al. 2019, Ikeda-Castrillon et al. 2022, Wantzen et al. 2023) and on the Hidrovia (Hamilton 1999, Gottgens et al. 2001, Coelho-Junior et al. 2022) and Girard et al. (submitted).

  1. Deepening the riverbed would result in lower water levels and the shrinking of the floodplain ecosystem. The dredging of the Tramo Norte reach aims to maintain a navigation channel at least 45 m wide and 2.1 m deep, for 90% of the year, including the dry season, resulting in an over-dredging of 30 cm at 17 critical sites (EVTEA 2015, Faria 2018). The increased capacity for the river channel to convey floodwaters would result in lower water levels and less back-flooding of the adjacent floodplains. Models based on satellite imagery show that lower Paraguay River levels would reduce the extent and duration of floodplain inundation. Lowering the river level by just 25 cm has been estimated to decrease the flooded area by approximately 4,000 to 6,000 km2 at low and high water, respectively (Hamilton 1999). The reduction of the flooded area will reduce the amount of aquatic habitat that serves as nurseries, feeding areas, and shelter for fish (Catella and Petrere_Junior 1996), waterfowl, and many other wetland-dependent species (Mourão et al. 2010, Campos et al. 2022). Reduced aquatic habitat during the dry season is of particular concern because the areas of permanent flooding, which are naturally limited in extent, are critical refugia for aquatic life. The negative effects on fish productivity will impact the artisanal and subsistence fishing, as well as fishing tourism, which is of great economic relevance in the region (Agostinho et al. (2001). Furthermore, projections of climate change for the region indicate that the seasonal drying of the floodplains will become more severe (Marengo et al. 2016).
  2. Shrinking of the wetland would change the socio-ecological structure of the Pantanal. The biodiversity and cultural diversity of the Pantanal depend on the natural flow regime, which determines the seasonal flood pulse that underpins floodplain ecosystem structure and function. The fundamental importance of the flood pulse for river and floodplain biota, culture, and ecological functions is described by numerous studies summarized in (Junk et al. 2011) and Chiaravalloti et al. (2022), which would be largely changed or even completely lost, as it has already been the case with the Mississippi and other rivers (Bayley 1991). The loss of active floodplains (in which most of the fish production and many other important ecological processes take place) will negatively impact the entire food chain and the human culture that goes along with it, for example,  fisheries, traditional cattle ranching, native cultures (Wantzen et al. 2023). Data on traditional communities livelihood and social network structures and dynamics suggests that a disruption of the flood regime and extension would affect their food security, access to traditional territories, and social networks (Chiaravalotti et al. 2022) and also the sustainable use of high-value natural products such as native rice species (Bertazzoni and Damasceno-Júnior 2011) in the future.
  3. The hydrological buffering effect of the Pantanal wetland would be largely lost. The Pantanal wetland acts as an enormous sponge, receiving the flood waters of the headwaters of the Paraguay River Basin, storing them temporarily, and gradually releasing water to the main stem. This results in a 3-month delay of the peak of the flood of the Paraguay River compared with the Paraná River at their confluence (da Silva and Girard 2004). Reduction of the hydrological buffering capacity of the Pantanal would result in an overlapping of the flood crests of both rivers, with potentially severe effects for the downriver areas in Argentina. The straightening and dredging of the Paraguay River channel would change the entire drainage dynamics of the Pantanal’s waters, which would drain more quickly, additionally contributing to drying out large portions of this enormous wetland. Flood dynamics would be modified, especially above the hardened sediment or rocky outcrops that act as control points for wetland back-flooding (Stevaux et al. 2020).
  4. Climatological feedbacks of the drainage of the Pantanal and interactions with climate change. The Pantanal acts as the “largest freshwater evaporation window in the world” (Por 1995) and thereby has enormous importance for the regional climate by contributing to cloud development and buffering temperature through air humidity. It can be anticipated that reduced flooding would have a strong negative effect on climate, which will add to already existing climate change effects, including prolonged drought and extreme heat, less predictable but more torrential rain events, and shortening of the rainy season (Marengo et al. 2016, Libonati et al. 2022). This means a further increase in the already-severe fire impacts (Tomas et al. 2021). The drying of areas containing sediments that have accumulated carbon over many years would result in the mineralization of this organic matter and a further release of greenhouse gases, further fueling actual global warming. The extent of flooding has decreased by 16% in the Paraguay River region in the past 10 years (Lázaro et al. 2020), with consequent negative ecological impacts (de Morais et al. 2022). The combined effects of drought and heat waves will substantially impact the floodplain ecosystems, altering the driving factors for vegetation distribution (Damasceno-Junior et al. 2022) and harming the health of livestock and human beings (Libonati et al. 2022).

Climate change projections indicate that the Paraguay River within the Pantanal is particularly vulnerable to decreased flows that would result in disruption of navigability by low water levels (Souza Junior et al. (2019). Extreme hydrological events have been strongly increasing in recent decades (Thielen et al. 2020). Even in the absence of climate change, occasional years of lower water levels will make navigation difficult or impossible (Girard et al. (submitted)).

  1. Potential increase of monocultures in the Pantanal. A collateral effect of the drainage of the Pantanal floodplain wetland would be the further pressures for the expansion of monocultures such as soybeans, sugar cane, corn, cotton and exotic pastures. Land conversion to crops is already advancing into the Pantanal from its outer parts, occupying drier areas exposed in the recent years. These cropping systems require control (elimination) of the natural flood pulse for efficient farming by implementing dikes and drainage systems, which will further degrade the Pantanal ecosystem. Satellite data from MapBiomas show how cultivated pastures have increasingly replaced the native vegetation in the last decades. This has a deleterious effect on biodiversity, for which the Pantanal is famous (Junk et al. 2006). Moreover, intensive agriculture entails the heavy use of pesticides, which end up in the aquatic food webs, and, ultimately, in human beings (de Oliveira Roque et al. 2021). The long-term sustainability of farming in the Pantanal is questionable because the drying of the plinthite soils, which are common in the floodplains, would eventually result in compacted soils that are not adequate for crops, as has already been observed in the Araguaia River floodplains (Santos et al. (2022).
  2. Ecological effects of dredging on the river morphology. The Paraguay River is a classic “sandy river” (Wantzen et al. 2014), characterized by mobile sand bars (Macedo et al. 2019) and diverse riparian habitats (Wantzen et al. 2005), which all depend on the natural dynamics of the sediment deposition and remobilization. Dredging will impair these natural dynamics and, consequently, all biota that depend on it. Like in other rivers worldwide that undergo sand removal, locally increased erosion and bank slumping will follow, resulting in a vicious cycle of ever-more severe dredging. Previously stable bank habitats, including important cultural sites such as the multi-centennial “Indio Grande” archeological site downstream of Cáceres, have already been degraded by dredging and navigation (Wantzen et al. 1999). The destination of the dredged sand is uncertain, but it is usually deposited in lateral floodplains and lakes, where it would bury important aquatic  habitats. While dredging at one side of the river, the sand is deposited on the other side, and some of the riverside tourist hotels already have their entrances blocked by sand deposition during the dry season (authors, personal observations). The analysis of the Technical, Economic and Environmental Viability Report of the Hidrovia (Faria 2018) indicates that, in the northern part of the Paraguay River, the main areas in need of dredging are located between the Taiamã Ecological Station and the Pantanal National Park, which represents the best preserved area of the Pantanal with a very high ecological and cultural value. Further downstream, the rocky outcrops along the Amolar mountains and the Taquari megafan represent hydrological bottlenecks regulating the flow of floods in the Pantanal by back-flooding the Paraguay River (Stevaux et al. 2020). Dredging the river in these reaches will modify the natural hydrologic dynamics, producing deleterious effects on aquatic and floodplain ecosystems and food webs, while potentially also causing geomorphological changes in the river that are not foreseeable and would create impacts that are not well understood
  3. Ecological effects of river straightening. In the northernmost reaches of the Paraguay River the river main channel has a very high sinuosity, meandering in narrow curves (Wantzen et al. 2005). Much of the river’s flow exits the channel onto the floodplain. From the perspective of navigation, this water loss to the floodplain as well as the narrow and meandering channels are problematic. Many meanders have already been dredged in their inner curves; some have already been cut through or are planned to become “straightened”. This reduces the thalweg length of the river bed and increases the capacity of the river to carry water, which in turn would allow it to erode its bed, resulting in a further channel incision, disconnection of floodplain habitats, and lowering of the groundwater level, as it was seen in other large rivers (e.g., Upper Rhine, (Wantzen et al. 2021)). These kinds of alterations of the dynamic hydrology of connected river-floodplain ecosystems have severely degraded ecological processes and biodiversity in rivers throughout the world (Tockner and Stanford 2002).
  4. Direct ecological and sedimentological impacts by navigation. The rivers of the Pantanal have been sustainably used for navigation with small vessels for centuries, but the desire to make the upper Paraguay River navigable for larger barge tows is incompatible with the dimensions and ecohydrological dynamics of the river system. Even if it was possible to provide sufficient depth and space for barge tows, the barge traffic itself would produce enormous damage, as observed during earlier phases of unlicensed navigation (Wantzen et al. 1999). Potential impacts include:


  1. Wave action resulting in bank erosion, bank slumping (resulting in riparian habitat loss), and the faster infilling of the dredged areas with sediment as well as of natural scour holes in the river, which represent essential habitats for large fish species;
  2. Sediment accumulation in the natural connections between the river and floodplain lakes, resulting in the disconnection of these habitats, so that fish cannot migrate back into the mainstem and get trapped and killed during the dry season;
  3. Especially during low flows when the seasonal fish migration (piracema) begins, fish shoals are likely to be hit by the propellers of the tow boats. Combined with the already-observed effects of upstream damming on loss of spawning habitats (Ely et al. 2020) and climate change effects (Peluso et al. 2023), this would be deleterious for the fish populations;
  4. Previously observed barge traffic has shown damage the meander banks (e.g., ripping off vegetation from the riverbanks). The current practice in the lower sections of the Paraguay River is to disassemble larger barge tows for passage through in meander bends, reassembling them later on, which is causing an enormous disturbance in the ecosystems;
  5. Pollution can be anticipated, e.g., by release of oil from engines, or littering of plastic and sewage. Occasional severe impacts can be anticipated, including unintentional releases of chemicals or cargo into the river, including oxygen consumption by rotting soybeans (if stranded barges need to be lightened) or eutrophication from the fertilizers that are transported upstream, potentially causing fish kills. In the event of an oil spill, particularly when the floodplain is inundated, extensive areas with a high degree of ecological value could be contaminated, and their cleanup would be extraordinarily difficult.


  1. Sociological and cultural effects. The Pantanal and adjacent areas of the Upper Paraguay River Basin have been cultural landscapes for many millennia (see, e.g., map of Sacred Places and description of the Pantaneiro lifestyle in Wantzen et al. (2023) and see Chiaravalloti et al. (2022) for an analysis of cultural ecosystem services). For nearly three centuries, Indigenous, African, and Luso-Brazilian cultures have combined to create a Pantaneiro lifestyle in harmony with the natural setting, well adapted to life in the rhythm of the waters including seasonal inundation of much of the land. This includes a respectful and sustainable use of natural resources, providing tight relationships with nature, and a a diversity of activities including fishing, ecotourism, and cattle ranching. Modification of the environmental structures and the resulting ecosystem services represents a strong driver of change for the local cultural diversity (da Silva et al. 2015). Soybean monoculture, intensive cattle ranching, agribusiness in general, and the transport of its products in an engineered river channel represent the exact opposite to the Pantaneiro lifestyle. Longstanding local and regional cultures, including five First Nations, would be alienated, made obsolete, and expelled from their original territories. In the areas where the port facilities are planned, the social structure would be negatively impacted, changing its current low-intensity economy and strong cultural linkages between nature and people (including fishers, tourists, and the local inhabitants).
  2. Economic effects. The initial plan to build the Hidrovia was proven to be economically unfeasible (Bucher and Huszar 1995, Huszar 1998). It is obvious that due to the sandy sediment structure of the river bottom, dredging will become an infinite task, causing the environmental damage described above, but also incurring enormous direct maintenance costs. As noted above, the navigable sector downriver of Corumbá was completely impassable for long periods during the dry seasons of 2019–2022. To compensate for the cessation of river transport, transport of minerals and grains shifted more to the BR-262 highway, where it damaged public infrastructure, caused innumerous accidents, and increased wildlife mortality due to road kills, including several endangered species (see Pinto et al. (2021)). It can be anticipated that this will happen more in the coming years. The impassability due to low water levels will be an even more serious problem in the reaches above Corumbá because the river channel is much shallower, more sinuous, and narrower. The construction of the port facilities will represent enormous investments, representing “too big to fail” situations, i.e., once they have been constructed, they may be maintained “whatever it costs”, even if this included further investments. Once established, few people would be required to work in these facilities, in contradiction to the idea that this would be beneficial for local job creation. Due to the loss of scenic beauty, biocultural diversity and natural resources, the the economic potential for ecological and fishing tourism, which is currently playing an important role in the regional economies, will be strongly diminished (estimates for revenues by fishing in million USD p.a.: commercial: 30; tourism 24; other: 300, (ANA 2021)).
  3. Facilitation of invasions of exotic species. The transformation of a natural river-floodplain environment into an industrial waterway will harm the native plant and animal communities and the people and economic activities that depend on them (Blettler et al. 2023). On the other hand, invasive exotic species will likely proliferate. For example, the invasive golden mussel (Limnoperna fortunei) was introduced by transoceanic vessels to the river system and then transported upriver by river vessels, and is now spreading in the Paraguay River system (Marchese et al. 2005, Oliveira et al. 2010), causing negative impacts by biofouling underwater surfaces including water intakes for towns and hydropower. The stabilization of river banks with rip-rap (stones) and sea walls, as is commonly necessary where heavy barge traffic exists, creates a novel habitat that benefits invasive species, as has been shown in other river systems (Wantzen et al. 2021).
  4. Water resources policies. Water resources management in Brazil is flawed regarding the use of rivers for navigation, failing to avoid the degradation of water quality or to consider conflicts with other uses. Water use for navigation is not clearly defined among activities requiring water use permits (“concessão de uso”). The only mention refers to the need for a sustainability certificate from the National Water Agency, demonstrating that the work contributes to increasing the level of water use in the basin, without any environmental consideration. In addition, the absence of a functional River Basin Committee for the Paraguay River Basin, as prescribed by the country's water resources legislation make the participation of the society in the decision-making process regarding water management in this basin difficult. In the Paraguay Hydrographic Region Water Resources Plan, a political instrument that guides the management of the upper Paraguay River (defined in Law 9433/1997), the entire reach from Cáceres to Corumbá was classified as navigable, overlapping the existing and proposed areas of restriction of use in the plan, despite projections for a tripling of commodity transport on the river by 2031.
  5. Potential follow-up actions. The maintenance of flow in navigable rivers often depends on a system of upriver dams. The Pantanal is already suffering from modifications of the natural flow regime by the Manso dam (Zeilhofer and de Moura 2009), which releases more water during the dry season and retains water during the wet season. Based on the previously established law to protect the last important fishing rivers in Mato Grosso, the State environmental agency (SEMA-MT) just denied licenses for 6 additional dams on the Cuiabá River mainstem, the most important tributary to the Paraguay River. However, the pressure to implement hydroelectric power plants in the Paraguay River basin is still enormous. Additionally, it could be argued that dams are desirable to keep the Paraguay River navigable all year long. Moreover, the recent Hidrovia proposals do not anticipate the blasting of the rocky outcrops that exist along the Caceres-Porto Murtinho reach, which was one of the main arguments that resulted in the rejection of the first plan to build the Hidrovia. One critical location is the Fecho do Morros granite outcrops located north of Porto Murtinho, considered one of the most important regulators of the Paraguay river flow. However, pressure to remove outcrops will certainly arise again, once the dredging proves insufficient to allow the passage of the enormous barge tows. Earlier plans to include navigation on tributary rivers to Paraguay, such as the Cuiabá and São Lourenço rivers, also may arise again, further increasing the risks of environmental and cultural impacts.


The Pantanal is the last large landscape in Central South America that still has a near-natural structure. It represents the biocultural heritage of the Brazilian people and the entire world, having the status as UNESCO World Heritage, Biosphere and Ramsar sites. It should not be destroyed for the sake of short-term gains of a very restricted group of people but to the detriment of all. Its existence depends on the natural flow regime, which provides a natural flood-and-drought pattern in a vast area. Increased dredging and disturbance of the flow regime will cause a multitude of negative impacts with unknown synergetic effects and unpredictable consequences. The ecological, social and economic collateral damages would be much higher than the economic benefits of reduced truck transport. It is obvious that an expansion and implementation of the Hidrovia plan would go in the opposite direction to the recent agreements to which Brazil is a signatory to, such as Sustainable Development Goals, the Convention on Biological Diversity, the Ramsar Convention, and the Climate Agenda. These should be respected and the federal law for the conservation of the entire biome, provided for in the constitution, urgently needs to be created and put into practice.The most feasible and sustainable solution would be the construction and restoration of the railway system in order to develop a sustainable means of commodity transport, and thus sparing the Paraguay river and the Pantanal wetlands.

This white paper has been written to inform political decision-makers, managers, NGOs and academia. It has been assembled by professionals who have decades of research experience on the ecology, socio-economy and hydrology of the Pantanal wetland and Paraguay river systems, and published or edited > 500 publications on these topics:

Karl M. Wantzen, Professor in River Ecology and UNESCO Chair “Rivers and Heritage”, Universities of Tours and Strasbourg, France

Mario L. Assine, Departamento de Geologia, Universidade Estadual Paulista - UNESP, Rio Claro, SP, Brazil

Danilo Bandini Ribeiro, Instituto de Biociencias, Universidade Federal de Mato Grosso do Sul, Campo Grande, MS, Brazil

Ieda Maria Bortolotto, Professor in Botany, Universidade Federal de Mato Grosso do Sul, Campo Grande, MS, Brazil

Debora F. Calheiros, PhD in Sciences, Embrapa and Ministério Público Federal, Corumbá, MS, Brazil

Zilca Campos, PhD in Ecology, Laboratório de Vida Selvagem, Embrapa Pantanal, Corumbá, MS, Brazil

Agostinho Carlos Catella, PhD in Ecology, Embrapa Pantanal, Corumbá, MS, Brazil

Rafael Morais Chiaravalotti, Associate Professor, Anthropology Department, University College London, London, United Kingdom

Eduardo Guimarães Couto, Soil Scientist, Retired professor and Associated Researcher at the Graduate Program in Tropical Agriculture, Federal University of Mato Grosso

Geraldo Alves Damasceno-Junior, Botanist, Professor of Vegetation Ecology at the Federal University of Mato Grosso do Sul, Brazil

Carolina Joana da Silva, Professor in Limnology, Universidade do Estado de Mato Grosso, President of the  National Committee of the UNESCO Biosphere of the Pantanal, Cáceres, MT, Brazil

Adalberto Eberhard, founder and former president of the NGO Ecotropica and manager of conservation sites near the Pantanal National Park, Cuiabá, MT, Brazil

Alexandre Ebert – Forest engineer, researcher at the Instituto Nacional de Áreas Úmidas and in the Programme in Ecology and Biodiversity conservation, Universidade Federal de Mato Grosso, Cuiabá, MT, Brazil

Pierre Girard, Professor in Hydrology, Federal University of Mato Grosso, Pantanal Research Center, Brazil

Stephen K. Hamilton, Professor Emeritus, Michigan State University and Senior Scientist, Cary institute of Ecosystem Studies, USA

Solange Ikeda-Castrillon, Professor in Ecology, Universidade do Estado de Mato Grosso, Cáceres, MT, Brazil

Renata Libonati, Professor in Meteorology, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil

Reinaldo Lourival, Terra Brasilis Institute and San Diego State University Associate Researcher, Center for Brazilian Studies. Brasilia DF. Brazil 

Hudson de Azevedo Macedo, Professor in Geography, Universidade Federal de Mato Grosso do Sul (UFMS) Campus do Pantanal (CPAN), Corumbá, MS, Brazil

Daniela Maimoni de Figueiredo, Limnologist and professor in Water Resources Management, Federal University of Mato Grosso, Cuiabá, MT, Brazil

José Marcato Junior, Professor in Geography, Universidade Federal de Mato Grosso do Sul, Campo Grande, MS, Brazil

Lucia Mateus, Fisheries ecologist and Professor in Ecology, Universidade Federal de Mato Grosso (UFMT), Cuiabá, MT, Brazil

Ronaldo Morato, Instituto Chico Mendes de Conservação da Biodiversidade, National Research and Conservation Center for Mammals (ICMBio/CENAP), Atibaia, SP, Brazil

Claumir Cesar Muniz - Fisheries ecologist and Professor in Ecology, Universidade do Estado de Mato Grosso, Cáceres, MT, Brazil

Catia Nunes da Cunha, Vegetation ecologist and Professor in Ecology, Instituto Nacional de Ciencia e Tecnologia em Áreas Úmidas, Cuiabá, MT, Brazil

Marcia Divina de Oliveira, PhD in Ecology, Embrapa Pantanal, Corumbá, MS, Brazil

Carlos Roberto Padovani, PhD in Ecology, Embrapa Pantanal, Corumbá, MS, Brazil

Fabio de Oliveria Roque, Professor in biodiversity conservation and territorial Planning at the Federal Universiy of Mato Grosso do Sul, Brazil, Campo Grande, MS, Brazil

Jerry Penha, Fisheries Ecologist and Professor in Ecology, Universidade Federal de Mato Grosso, Cuibá, MT, Brazil

Aguinaldo Silva, Professor in Geomorphology, Universidade Federal de Mato Grosso do Sul – Câmpus do Pantanal, Corumbá, MS, Brazil

Ernandes Sobreira Oliveira Junior - Biogeochemist and Professor in Ecology, Universidade do Estado de Mato Grosso, Cáceres, MT, Brazil

Balbina Soriano, PhD in Ecology, Embrapa Pantanal, Corumbá, MS, Brazil

Wilson Cabral de Sousa Junior, Researcher at the Infrastructure, Environment and Sustainability Studies Group – NINFA/Instituto Tecnologico da Aeronáutica, Brazil

Walfrido Moraes Tomas, PhD in Ecology, Researcher, Embrapa Pantanal, Corumbá, MS, Brazil

Catia Urbanetz. PhD in Ecology, Embrapa Pantanal, Corumbá, MS, Brazil 


The United Nations has declared the period between 2018 and 2028 the “UN Water Action Decade” to focus on the water-related issues connected to the Sustainable Development Goals. During its midterm review in New York in March 2023, it became clear that climate change urges global and local water stakeholders to take more and better action. In the Blue Action Papers, we publish papers on urgent water issues from a social and cultural perspective, as part of our commitments made during the recent UN Conference. These pieces are peer-reviewed by members of the PortCityFutures community, and edited by the PortCityFutures editorial team in close conjunction with the Blue Papers editorial team: Carola Hein, Hilde Sennema, Vincent Baptist and Foteini Tsigoni.



Agostinho, A. A., L. C. Gomes, and M. Zalewski. 2001. The importance of floodplains for the dynamics of fish communities of the upper river Paran Ecohydrology & Hydrobiology 1:209-217.

ANA. 2021. Estudos de avaliação dos efeitos da implantação de empreendimentos hidrelétricos. Online report, accessed 20. May 2023.

Bayley, P. B. 1991. The flood pulse advantage and the restoration of river-floodplain systems. Regulated Rivers Research & Management 6:75-86.

Bertazzoni, E. C., and G. A. Damasceno-Júnior. 2011. Aspectos da biologia e fenologia de Oryza latifolia Desv. (Poaceae) no Pantanal sul-mato-grossense. Acta Botanica Brasilica 25:476-786.

Blettler, M., L. A. Espínola, and V. Berros. 2023. Bio- and Cultural Diversity in The Middle Paraná River. Pages 537-559 in K. M. Wantzen, editor. River Culture: Life as a dance to the rhythm of the waters. UNESCO publishing, Paris.

Brasil. 1988. Constituição da República Federativa do Brasil de 1988, accessed 18. May 2023.

Bucher, E. H., and P. C. Huszar. 1995. Critical environmental costs of the Paraguay-Paraná waterway project in South America. Ecological Economics 15:3-9.

Cabral de Sousa Júnior, W. 2019. Nova hidrovia Paraguai-Paraná [recurso eletrônico] : uma análise abrangente : análise de conjuntura e factibilidade política, econômica, social e ambiental da “nova” proposta da hidrovia Paraguai-Paraná Mupan, Campo Grande, MS

Campos, Z., G. Mourão, F. d. L. MUNIZ, F. Maffei, R. Botero-Arias, and W. E. Magnusson. 2022. Direções para mitigar os impactos da seca extrema nas populações de jacarés (Caiman Yacare) no Pantanal.

Catella, A. C., and M. Petrere_Junior. 1996. Feeding patterns in a fish community of Baia da Onça, a floodplain lake of the Aquidauana River, Pantanal, Brazil. Fisheries Management and Ecology 3:229-237.

Chiaravalloti, R. M., F. Bolzan, F. d. O. Roque, and S. Biswas. 2022. Ecosystem services in the floodplains: Socio-cultural services associated with ecosystem unpredictability in the Pantanal wetland, Brazil. Aquatic Ecosystem Health & Management 25:72-80.

Coelho-Junior, M. G., L. M. Diele-Viegas, D. F. Calheiros, E. C. Silva Neto, P. M. Fearnside, and L. Ferrante. 2022. Pantanal port licence would threaten the world’s largest tropical wetland. Nature Ecology & Evolution 6:484-485.

da Silva, C. J., and P. Girard. 2004. New challenges in the management of the Brazilian Pantanal and catchment area. Wetlands Ecology and Management 12:553-561.

da Silva, C. J., K. N. Silva Sousa, S. K. Ikeda-Castrillon, C. R. A. S. Lopes, J. R. da Silva Nunes, M. A. Carniello, P. R. Mariotti, W. L. Lazaro, A. Morini, B. W. Zago, C. L. Façanha, R. Albernaz-Silveira, E. Loureiro, I. G. Viana, R. F. d. Oliveira, W. J. Alves da Cruz, J. C. de Arruda, N. L. Sander, D. S. de Freitas Junior, V. R. Pinto, A. C. de Lima, and R. H. G. Jongman. 2015. Biodiversity and its drivers and pressures of change in the wetlands of the Upper Paraguay–Guaporé Ecotone, Mato Grosso (Brazil). Land Use Policy 47:163-178.

Damasceno-Junior, G. A., A. d. M. M. Pereira, J. Oldeland, P. Parolin, and A. Pott. 2022. Fire, Flood and Pantanal Vegetation. Pages 661-688  Flora and Vegetation of the Pantanal Wetland. Springer.

de Morais, M., M. S. A. Abdo, C. dos Santos, N. L. Sander, J. R. da Silva Nunes, W. L. Lázaro, and C. J. da Silva. 2022. Long-term analysis of aquatic macrophyte diversity and structure in the Paraguay river ecological corridor, Brazilian Pantanal wetland. Aquatic Botany 178:103500.

de Oliveira Roque, F., A. Guerra, M. Johnson, C. Padovani, J. Corbi, A. P. Covich, D. Eaton, W. M. Tomas, F. Valente-Neto, and A. C. P. Borges. 2021. Simulating land use changes, sediment yields, and pesticide use in the Upper Paraguay River Basin: Implications for conservation of the Pantanal wetland. Agriculture, Ecosystems & Environment 314:107405.

Ely, P., I. Fantin-Cruz, H. M. Tritico, P. Girard, and D. Kaplan. 2020. Dam-Induced Hydrologic Alterations in the Rivers Feeding the Pantanal. Frontiers in Environmental Science 8.

EVTEA. 2015. Estudo da Viabilidade Técnica, economica e Ambiental da Hidrovia do Rio Paraguai. Volume 1. Relatório de Estudo - EVTEA. 152 p. Available in

Faria, A. 2018. Análise sobre o Estudo de Viabilidade Técnica, Econômica e Ambiental (EVTEA) Da Hidrovia Paraná-Paraguai. Ecoa – Ecologia e Ação,, 14 de julho, 3169, Centro – Campo Grande, MS CEP: 79002-333, Brazil.

Girard_et_al. submitted. Expansion of fluvial transport of commodities through the Pantanal floodplains of Brazil: Potential impacts and interference by climate change.

Gottgens, J. F., J. E. Perry, R. H. Fortney, J. E. Meyer, M. Benedict, and B. E. Rood. 2001. The Paraguay-Paraná Hidrovía: Protecting the Pantanal with Lessons from the PastLarge-scale channelization of the northern Paraguay-Paraná seems to be on hold, but an ongoing multitude of smaller-scale activities may turn the Pantanal into the next example of the “tyranny of small decisions”. BioScience 51:301-308.

Hamilton, S. K. 1999. Potential effects of a major navigation project (Paraguay-Parana Hidrovia) on inundation in the Pantanal floodplains. Regulated Rivers-Research & Management. 15:298-299.

Huszar, P. C. 1998. Overestimated benefits and underestimated costs: the case of the Paraguay—Paraná navigation study. Impact Assessment and Project Appraisal 16:295-304.

Ikeda-Castrillon, S. K., E. S. Oliveira-Junior, O. C. Rossetto, C. H. Saito, and K. M. Wantzen. 2022. The Pantanal: A Seasonal Neotropical Wetland Under Threat. Pages 1-27 in C. Constance, editor. The Palgrave Handbook of Global Sustainability. Palgrave-McMillan, Basingstoke, Hampshire, England.

Junk, W. J., C. N. da Cunha, K. M. Wantzen, P. Petermann, C. Strussmann, M. I. Marques, and J. Adis. 2006. Biodiversity and its conservation in the Pantanal of Mato Grosso, Brazil. Aquatic Sciences 68:278-309.

Junk, W. J., J. C. da Silva, C. Nunes da Cunha, and W. K. M., editors. 2011. The Pantanal: Ecology, biodiversity and sustainable management of a large neotropical seasonal wetland. Pensoft Publishers, Sofia

Lázaro, W. L., E. S. Oliveira-Júnior, C. J. d. Silva, S. K. I. Castrillon, and C. C. Muniz. 2020. Climate change reflected in one of the largest wetlands in the world: an overview of the Northern Pantanal water regime. Acta Limnologica Brasiliensia 32.

Libonati, R., J. L. Geirinhas, P. S. Silva, D. Monteiro dos Santos, J. A. Rodrigues, A. Russo, L. F. Peres, L. Narcizo, M. E. Gomes, and A. P. Rodrigues. 2022. Drought–heatwave nexus in Brazil and related impacts on health and fires: A comprehensive review. Annals of the new York Academy of Sciences 1517:44-62.

Marchese, M. R., K. M. Wantzen, and I. E. de Drago. 2005. Benthic invertebrate assemblages and species diversity patterns of the Upper Paraguay River. River Research and Applications 21:485-499.

Marengo, J. A., G. S. Oliveira, and L. M. Alves. 2016. Climate Change Scenarios in the Pantanal. Pages 227-238 in I. Bergier and M. L. Assine, editors. Dynamics of the Pantanal wetland in South America. Springer International Publishing, Cham.

Mourão, G., W. Tomas, and Z. Campos. 2010. How much can the number of jabiru stork (Ciconiidae) nests vary due to change of flood extension in a large Neotropical floodplain? Zoologia (Curitiba) 27:751-756.

Oliveira, M. D., S. K. Hamilton, D. F. Calheiros, C. M. Jacobi, and R. O. Latini. 2010. Modeling the potential distribution of the invasive golden mussel Limnoperna fortunei in the Upper Paraguay River system using limnological variables. Brazilian Journal of Biology 70:831-840.

Peluso, L. M., L. Mateus, J. Penha, Y. Súarez, and P. Lemes. 2023. Climate change may reduce suitable habitat for freshwater fish in a tropical watershed. Climatic Change 176:44.

Pinto, F. A. S., A. Bager, R. C. Cerqueira, A. P. Milagres, B. C. Morais, P. B. A. da Silva, E. Castro, E. P. Medici, A. L. Desbiez, and F. R. Tortato. 2021. Diagnosis on the mammal road-kills in the Upper Paraguay River Basin (in port.). Boletim Do Museu Paraense Emílio Goeldi-Ciências Naturais 16:441-458.

Por, F. D. 1995. The Pantanal of Mato Grosso (Brazil). World's largest wetlands. Kluwer Academic Publisher, Dordrecht.

Santos, D. P., G. G. Santos, V. Á. de Oliveira, G. C. da Silva, R. A. Flores, A. C. Azevedo, V. S. de Souza Júnior, and M. G. Pereira. 2022. Probable causes of hardening of redoximorphic features in Plinthosols of the Araguaia River floodplain, Central region of Brazil. Geoderma Regional 31:e00583.

Stevaux, J. C., H. de Azevedo Macedo, M. L. Assine, and A. Silva. 2020. Changing fluvial styles and backwater flooding along the Upper Paraguay River plains in the Brazilian Pantanal wetland. Geomorphology 350:106906.

Thielen, D., K.-L. Schuchmann, P. Ramoni-Perazzi, M. Marquez, W. Rojas, J. I. Quintero, and M. I. Marques. 2020. Quo vadis Pantanal? Expected precipitation extremes and drought dynamics from changing sea surface temperature. PloS one 15:e0227437.

Tockner, K., and J. A. Stanford. 2002. Riverine flood plains: present state and future trends. Environmental Conservation 29:308-330.

Tomas, W. M., C. N. Berlinck, R. M. Chiaravalloti, G. P. Faggioni, C. Strüssmann, R. Libonati, C. R. Abrahão, G. do Valle Alvarenga, A. E. de Faria Bacellar, and F. R. de Queiroz Batista. 2021. Distance sampling surveys reveal 17 million vertebrates directly killed by the 2020’s wildfires in the Pantanal, Brazil. Scientific Reports 11:1-8.

Tomas, W. M., F. de Oliveira Roque, R. G. Morato, P. E. Medici, R. M. Chiaravalloti, F. R. Tortato, J. M. F. Penha, T. J. Izzo, L. C. Garcia, R. F. F. Lourival, P. Girard, N. R. Albuquerque, M. Almeida-Gomes, M. H. d. S. Andrade, F. A. S. Araujo, A. C. Araujo, E. C. d. Arruda, V. A. Assunção, L. D. Battirola, M. Benites, F. P. Bolzan, J. C. Boock, I. M. Bortolotto, M. d. S. Brasil, A. R. Camilo, Z. Campos, M. A. Carniello, A. C. Catella, C. C. Cheida, P. G. Crawshaw, S. M. A. Crispim, G. A. D. Junior, A. L. J. Desbiez, F. A. Dias, D. P. Eaton, G. P. Faggioni, M. A. Farinaccio, J. F. A. Fernandes, V. L. Ferreira, E. A. Fischer, C. E. Fragoso, G. O. Freitas, F. Galvani, A. S. Garcia, C. M. Garcia, G. Graciolli, R. D. Guariento, N. M. R. Guedes, A. Guerra, H. M. Herrera, R. Hoogesteijn, S. C. Ikeda, R. S. Juliano, D. L. Z. K. Kantek, A. Keuroghlian, A. C. R. Lacerda, A. L. R. Lacerda, V. L. Landeiro, R. R. Laps, V. Layme, P. Leimgruber, F. L. Rocha, S. Mamede, D. K. S. Marques, M. I. Marques, L. A. F. Mateus, R. N. Moraes, T. A. Moreira, G. M. Mourão, R. D. Nicola, D. G. Nogueira, A. P. Nunes, C. d. Nunes da Cunha, M. D. Oliveira, M. R. Oliveira, G. M. Paggi, A. O. Pellegrin, G. M. F. Pereira, I. A. H. F. S. Peres, J. B. Pinho, J. O. P. Pinto, A. Pott, D. B. Provete, V. D. A. dos Reis, L. K. dos Reis, P.-C. Renaud, D. B. Ribeiro, O. C. Rossetto, J. Sabino, D. Rumiz, S. M. Salis, D. J. Santana, S. A. Santos, Â. L. Sartori, M. Sato, K.-L. Schuchmann, E. Scremin-Dias, G. H. F. Seixas, F. Severo-Neto, M. R. Sigrist, A. Silva, C. J. Silva, A. L. Siqueira, B. M. A. Soriano, L. M. Sousa, F. L. Souza, C. Strussmann, L. S. M. Sugai, N. Tocantins, C. Urbanetz, F. Valente-Neto, D. P. Viana, A. Yanosky, and W. J. Junk. 2019. Sustainability Agenda for the Pantanal Wetland: Perspectives on a Collaborative Interface for Science, Policy, and Decision-Making. Tropical Conservation Science 12:1940082919872634.

Tortato, F., W. M. Tomas, R. M. Chiaravalloti, and R. Morato. 2022. Tragedy of the Commons: How Subtle,“Legal” Decisions Are Threatening One of the Largest Wetlands in the World. BioScience 72:609-609.

UNESCO. 2000. Pantanal Conservation area,, accessed 18. May 2023.

Wantzen, K. M., M. C. M. Blettler, M. R. Marchese, M. L. Amsler, M. Bacchi, I. D. Ezcurra de Drago, and E. E. Drago. 2014. Sandy rivers: a review on general ecohydrological patterns of benthic invertebrate assemblages across continents. International Journal of River Basin Management 12:163-174.

Wantzen, K. M., C. J. da Silva, D. M. Figueiredo, and M. C. Migl cio. 1999. Recent impacts of navigation on the Upper Paraguay River. Revista Boliviana de Ecologia 6:173-182.

Wantzen, K. M., E. Drago, and C. J. da Silva. 2005. Aquatic habitats of the Upper Paraguay River-Floodplain-System and parts of the Pantanal (Brazil). Ecohydrology & Hydrobiology 21:1-15.

Wantzen, K. M., P. Girard, F. O. Roque, C. Nunes da Cunha, R. M. Chiaravalloti, A. V. Nunes, I. M. Bortolotto, A. Guerra, C. Pauliquevis, M. Friedlander, and J. Penha. 2023. The Pantanal: How long will there be Life in the Rhythm of the Waters?in K. M. Wantzen, editor. River Culture – Life as a dance to the rhythm of the waters. . UNESCO Publishing, Paris

Wantzen, K. M., U. Uehlinger, G. Van der Velde, R. S. E. W. Leuven, L. Schmitt, and J. N. Beisel. 2021. The Rhine River Basin. Pages 333-391 in K. Tockner and C. T. Robinson, editors. Rivers of Europe, 2nd Edition. Elsevier.

Zeilhofer, P., and R. M. de Moura. 2009. Hydrological changes in the northern Pantanal caused by the Manso dam: Impact analysis and suggestions for mitigation. Ecological Engineering 35:105-117.


1Summary of historical juridical decisions regarding the Hidrovia: Since 1996, the Brazilian government has not considered the Northern Branch (upper Paraguay River) of the proposed Hidrovia for large-scale, industrial navigation of barge tows. At the time, Transport Minister Eliseu Padilha considered the Hidrovia a relevant issue for President Fernando Henrique Cardoso, who stressed that the ships should adapt to the rivers, and not the other way around: "Whoever wants to transport goods in our territory will have to build ships that adapt to the riverbed. The interests of ship owners will not make us put at risk the ecosystem of the Pantanal Mato-grossense". In 2000, the Federal Public Ministry (MPF/MT) questioned the state licensing of a river port near Cáceres (Porto de Morrinhos), claiming that the licensing of navigation infrastructure on the Paraguay River, a federal river, should be the responsibility of the federal environmental management agency (IBAMA), and should be prioritized before the licensing of ports by the state(s). This Public Civil Action (PCA) led to a decision 20 years later by the Supreme Court of Justice, which determined the need for licensing of the waterway and the completion of an Integrated Environmental Assessment (AAI) by IBAMA. In 2020, the MPF/MT also filed another PCA in relation to nullifying the licensing of the ports in Cáceres - MT and Corumbá - MS, based on the previous PPA and the STJ's decision to conduct an SEA in the Northern Reach of the Paraguay River. This PCA is being evaluated by the Federal Court (TRF-Region 1), and considers the "Amicus Curiae" of civil society of the region questioning the licensing. Thus, the granting of the Preliminary License for two ports in Cáceres (Barranco Vermelho and Paratudal) and the renewal of the license of the Port of Cáceres, all in 2022 by SEMA-MT, as well as the Preliminary License in May 2023 of Porto Paraíso, in Corumbá-MS, granted by IMASUL -MS, are "under judgement" for not respecting the decisions of the STJ. In addition, there is a Recommendation no. 10/2018 of the Ramsar Convention on the Conservation of Wetlands of International Interest, for which Brazil is a signatory since 1993, which expressly recommends "the conservation of the sub-basins free of dams still remaining in the Upper Paraguay Basin and the Paraguay River in its Northern Branch". It is recommended that the "ANA and CNRH and the MinT and DNIT exclude the stretch of the Paraguay River called the North Branch, between Cáceres and Corumbá, from the possibility of industrial or large-scale navigation on the Paraguay-Paraná Waterway, since it is one of the extremely fragile stretches of the Paraguay-Paraná System of Humid Areas with respect to the hydrodynamic, sedimentological, biogeochemical, and ecological aspects of the Paraguay River, and to declare this stretch an ‘area with use restriction’ for large-scale navigation".

BR - Hidrovia Parana - Paraguay.pdf (1.33 MB)
DE - Hidrovia Parana - Paraguay.pdf (1.36 MB)
FR - Hidrovia Parana - Paraguay.pdf (1.23 MB)