Karl M. Wantzen

University of Tours | UFR · UMR CNRS 7324 Centre Interdisciplinaire Cités, Territoires, Environnement et Sociétés (CITERES)

Invasions of non-native species are considered major threats to biodiversity in urban waterbodies. We compared macroinvertebrate richness, density, and community composition among three urban lakes with varying macrophyte covers: One dominated by the invasive macrophyte species Elodea nuttallii, one by the native species Myriophyllum spicatum, and...

Inland navigation in Europe is proposed to increase in the coming years, being promoted as a low-carbon form of transport. However, we currently lack knowledge on how this would impact biodiversity at large scales and interact with existing stressors. Here we addressed this knowledge gap by analysing fish and macroinvertebrate community time series...

Hong Kong (HK), one of the world’s most densely populated metropolises, is home to over 200 rivers and streams extending about 2500 km in length. During the 1970s–1990s, most of these rivers were converted into artificial canals, to which the local society pays little attention. Since the 2010s, the HK government has initiated river revitalization...

The resurgent navigation project known as the Hidrovia Paraguay-Paran´ a threatens the integrity of the Pantanal, the world’s largest wetland, which is considered a biome of its own. Intensive barge navigation is intended to transport crops (soybean, sugar, corn) and cement, iron and manganese from areas of production in Brazil, Paraguay and Bol...

O ressurgente projeto de navegação conhecido como Hidrovia Paraguai-Paraná ameaça a integridade do Pantanal, a maior área úmida do mundo, que é considerada um bioma próprio. A navegação intensiva por barcaças tem como objetivo transportar produtos agrícolas (soja, açúcar, milho) e cimento, ferro e manganês das áreas de produção no Brasil, Paraguai...

Organic and peat soils are the most efficient terrestrial carbon storages holding 25 percent of the global soil organic carbon, on only 3 percent of the global land surface (UNEP, 2022). Wetlands in Cerrado stream valleys – wet grassland, Veredas and riparian swamp forests - harbour peat soils with a high concentration of organic matter, but they h...

El río Paraná y su planicie de inundación en Argentina se encuentran dentro de las más grandes del mundo. El régimen de inundación y las temperaturas son generalmente consideradas como variables claves, gobernando los procesos ecológicos a través de diversas escalas espaciales y temporales. De forma general, la variación del nivel de agua, conectan...

Rivers are the main pathway for microplastics (MP) transport toward the ocean. However, the understanding of the processes involved in the deposition and mobilization of MP in rivers, specifically in sediment side bars (SB), remains very limited. The objectives of this study were: (i) to examine the effect of hydrometric fluctuations and wind inten...

This paper discusses barriers and presents recommendations for the effective restoration of riverine and coastal wetlands in Europe, highlighting the importance of integrating initiatives across science, policy and practice.

Riverfronts in cities provide critical ecological, social, and cultural services for urban citizens; many have been transformed into public parks with blue and green infrastructures to build flood resilience while providing co-benefits for society. The Urban Human-River Encounter Sites (UHRES) approach helps drive and shape human-nature interaction...

Mega-damming, pollution and depletion endanger rivers worldwide. Meanwhile, modernist imaginaries of ordering ‘unruly waters and humans’ have become cornerstones of hydraulic-bureaucratic and capitalist development. They separate hydro/social worlds, sideline river-commons cultures, and deepen socio-environmental injustices. But myriad new water ju...

An unbelievably small portion of the water available on planet Earth, just 0.00015 per cent of it, runs in rivers (Garcia-Moreno et al. 2014). And yet, this is the most important water source, not only for humans, but also for animals, plants and entire ecosystems on all continents. The natural flow regime of rivers, including periods of floods and...

Improving collection technologies is crucial to develop effective and economically feasible solutions for catching plastic from riverine environments. However, floating booms are being constructed and deployed in river around the world without rigorously testing its effectiveness. In this study, we tested the effectiveness of a boom under realistic...

Since ancient times, human civilization is linked to rivers, and these rivers maintain our lives like blood vessels. The Congo River connects Central Africa and its primary forest to the Atlantic Ocean and has been used as the main commercial route for centuries till today. More than 75 million people and a unique fauna and flora live in the equato...

This book gives positive examples how humans and rivers have been, and are still in some places, living in harmony. It analyses how this knowledge can be transferred into modern river management schemes and thereby it attempts to mitigate the deplorable trend of the decline of biological and cultural heritages and diversities in and along rivers. A...

This article should be cited as: Wantzen, K.M.; Girard, P.; Roque, F.O.; Nunes da Cunha, C.; Chiaravalloti, R.M.; Nunes, A.V.; Bortolotto, I.M.; Guerra, A.; Pauliquevis, C.; Friedlander, M.; Penha, J. (2023): The Pantanal: How long will there be Life in the Rhythm of the Waters? In: Wantzen, K.M. (ed.): River Culture-Life as a Dance to the Rhythm o...

Like a river, this book coalesced from different sources. During the formation of the River Culture concept and the first workshops organized by the UNESCO Chair in 2014, ideas for a book that synthesizes historical and present-day knowledge on both, the biological and cultural adaptations in floodplains, were drafted. The book gained momentum from...

This book gives positive examples how humans and rivers have been, and are still in some places, living in harmony. It analyses how this knowledge can be transferred into modern river management schemes and thereby it attempts to mitigate the deplorable trend of the decline of biological and cultural heritages and diversities in and along rivers. A...

This book gives positive examples how humans and rivers have been, and are still in some places, living in harmony. It analyses how this knowledge can be transferred into modern river management schemes and thereby it attempts to mitigate the deplorable trend of the decline of biological and cultural heritages and diversities in and along rivers. A...

This book gives positive examples how humans and rivers have been, and are still in some places, living in harmony. It analyses how this knowledge can be transferred into modern river management schemes and thereby it attempts to mitigate the deplorable trend of the decline of biological and cultural heritages and diversities in and along rivers. A...

This book gives positive examples how humans and rivers have been, and are still in some places, living in harmony. It analyses how this knowledge can be transferred into modern river management schemes and thereby it attempts to mitigate the deplorable trend of the decline of biological and cultural heritages and diversities in and along rivers. A...

This book gives positive examples how humans and rivers have been, and are still in some places, living in harmony. It analyses how this knowledge can be transferred into modern river management schemes and thereby it attempts to mitigate the deplorable trend of the decline of biological and cultural heritages and diversities in and along rivers. A...

This book gives positive examples how humans and rivers have been, and are still in some places, living in harmony. It analyses how this knowledge can be transferred into modern river management schemes and thereby it attempts to mitigate the deplorable trend of the decline of biological and cultural heritages and diversities in and along rivers. A...

This book gives positive examples how humans and rivers have been, and are still in some places, living in harmony. It analyses how this knowledge can be transferred into modern river management schemes and thereby it attempts to mitigate the deplorable trend of the decline of biological and cultural heritages and diversities in and along rivers. A...

This book gives positive examples how humans and rivers have been, and are still in some places, living in harmony. It analyses how this knowledge can be transferred into modern river management schemes and thereby it attempts to mitigate the deplorable trend of the decline of biological and cultural heritages and diversities in and along rivers. A...

This book gives positive examples how humans and rivers have been, and are still in some places, living in harmony. It analyses how this knowledge can be transferred into modern river management schemes and thereby it attempts to mitigate the deplorable trend of the decline of biological and cultural heritages and diversities in and along rivers. A...

Nature-based Solutions (NbS) gain popularity worldwide in the context of urban flood risk management. NbS for urban flood protection restore floodplains and lakes/ponds to retain periodic flooding and adopt green infrastructures to facilitate stormwater runoff. They are proven to be effective and able to provide co-benefits for human wellbeing. How...

The environmental management of rivers faces a substantial geographical problem: due to their elongate shape and their position at the valley bottom, the area that they cover is fragmented by territorial borders. Therefore, only very few river basins or substantial parts of them have yet been assigned as dedicated sites (nature reserves, parks, etc...

Many urban streams have vanished from the surface as a collateral effect of urban growth. Often, these buried streams have been forgotten, and only street names remind us of their existence. Reasons for stream burial include the gain of space for road or house construction or the use of stream water to transport wastewater. Today, restoration effor...

on the semi-arid Caatinga is lacking, but ~ 3% of the area may be occupied by riparian wetlands and other small wetland types, many of which are periodically dry. Riparian vegetation includes a very large richness in tree species. The amount and species richness of herbaceous plants depend on light availability. In-streams of the semi-arid region o...

The hydrological patterns of all natural water bodies are pulsing in variable rhythms of high and low water. The biodiversity of these ecosystems is driven by the changing nature of the environment, allowing different life strategies to coexist, i.e. the fast reuse of nutrients when aquatic biota flourish in the recently wetted zones and vice versa...

Change detection approaches based on historical maps are frequently used in fluvial geomorphology to re-construct long-term river trajectories and evaluate the level of functional degradation. On this basis, achievable rehabilitation goals may also be addressed. However, most of these studies explore the changes of land cover over time only through...

The present study is a full review of the non-native freshwater fish species introduced into Argentina and their relationship to the main environmental features and introduction vectors of each freshwater ecoregion. The total number of non-native freshwater fish species was compiled through a literature survey; information on spatial–temporal patte...

The present study is a full review of the non-native freshwater fish species introduced into Argentina and their relationship to the main environmental features and introduction vectors of each freshwater ecoregion. full-text access to a view-only: https://rdcu.be/cHy5z

In many countries of the Global South, aquatic ecosystems such as streams, rivers, lakes and wetlands are severely impacted by multiple environmental, anthropogenic and climatic stressors. In an earlier review (https://www. mdpi.com/2071-1050/11/18/4975), applying a DPSIR approach (Drivers, Pressures, State, Impacts, Responses), we analysed a serie...

The Rhine is a 1233 km-long pivotal river in Central Europe. Its catchment harbors about 60 million inhabitants in nine countries from the Alps to the North Sea. On most of its course, this heavily modified water body is managed in favor of industrial production, urbanization, and transport. The 1816 commission on navigability was the first Europea...

River ecosystem services (rESS) such as the provision of drinking water, fish and other foods, flood protection, or spaces for recreation are important to human well-being. We present methods, tools, and resources for measuring, mapping, assessing, and reporting on status and trends in rESS. Within this framing, we show current approaches to integr...

Wetlands play a much greater role in the global carbon cycle than their area share would suggest. Plant biomass production and restricted decomposition due to continuous soil water saturation make them important atmospheric carbon sinks. This fragile stage can quickly tip towards being atmospheric sources by droughts and drainages. Therefore, they...

CHAPTER IN GERMAN - Wetlands occur all over the world. In the tropical regions, depending on the level and regularity of the flooding and the type of soil, they are pronounced as dense forests, open savannahs or as swamps and extensive moors. The duration of the moisture phase is of decisive importance for soil formation and for the prevailing vege...

Plastic in the environment is considered an emerging pollutant of global concern. In spite of intensive research, many questions remain open, such as the processes that drive the deposition and remobilization of plastic debris on river beaches. The objectives of this study were: i) to analyze the influence of the natural hydrological fluctuations a...

Human welfare depends on the health of nature. Decades of ill-conceived management practices caused a decline in the quality of human life, as well as in biological and cultural diversity. Simultaneously, they increased social and ecological risks. For instance, mismanagement of urban rivers jeopardizes their ecological health and ability to provid...

Benthic macroinvertebrates colonize all types of lentic and lotic inland hydrosystems. Except for few purely marine groups, almost all taxonomic groups of invertebrates occur in freshwater. Due to their size from less than 1 mm to several centimeters and the amphibious life cycle of aquatic insects as one of the main groups, they are important acto...

Rivers support some of Earth’s richest biodiversity1 and provide essential ecosystem services to society2, but they are often fragmented by barriers to free flow3. In Europe, attempts to quantify river connectivity have been hampered by the absence of a harmonized barrier database. Here we show that there are at least 1.2 million instream barriers...

Vernal pools are small, shallow and ephemeral freshwater wetlands, often located in forests. Despite harboring high levels of biodiversity and being biochemical hotspots, they have been severely degraded by human activities. Restoration of vernal pools has become a priority for resource managers, and monitoring of restoration projects is needed to...

Plastic pollution has become a globally pressing environmental issue. In birds, plastic may cause harm by entangling or ingestion when used for nesting. The use of anthropogenic nesting material has so far been mostly studied in birds of terrestrial or marine habitats, but there are yet very few reports for inland water–associated birds. The aim of...

Since 2004, UNESCO has highlighted the theme of river and heritage, which was consolidated by the Africities Summit in 2006 in Nairobi, the Loire / Niger project in 2007-2008 and the Symposium River Heritage and territories as of 2011 in Saint- Louis (Senegal). Since 2014, the UNESCO Chair "Fleuves et Patrimoine / River Culture" (www.unesco-chair-r...

In many countries of the Global South, aquatic ecosystems such as streams, rivers, lakes, and wetlands are severely impacted by several simultaneous environmental stressors, associated with accelerated urban development, and extreme climate. However, this problem receives little attention. Applying a DPSIR approach (Drivers, Pressures, State, Impac...

The Giant Freshwater Pearl Mussel (Margaritifera auricularia) is one of the rarest invertebrate species worldwide. This two-volume book aims to bring together all the so far available information on the species. Both volumes are independent books, although they can be seen as complimentary, giving scientific and technical information. They result f...

The Giant Freshwater Pearl Mussel (Margaritifera auricularia) is one of the rarest invertebrate species worldwide. This two-volume book aims to bring together all the so far available information on the species. Both volumes are independent books, although they can be seen as complimentary, giving scientific and technical information. They result f...

The Giant Freshwater Pearl Mussel (Margaritifera auricularia) is one of the rarest invertebrate species worldwide. This two-volume book aims to bring together all the so far available information on the species. Both volumes are independent books, although they can be seen as complimentary, giving scientific and technical information. They result f...

The giant freshwater pearl mussel Margaritifera auricularia (GFPM) is one of the most endangered bivalve species in the world. Originally occurring in many European rivers, the GFPM is a relict now restricted to a few ageing populations in France and Spain in which natural reproduction is almost absent. Like most unionoid mussels, the GFPM needs ho...

Plastic pollution is one of the most acute environmental topics of our time. While there is a great scientific effort to tackle this problem, it has not always been well-coordinated or properly targeted. In this short review, we call for scientists to get involved in three crucial topics (threats) underestimated—or ignored—in freshwater systems: (i...

Rhodeus amarus is a cyprinid fish that spawns in the mantle cavity of freshwater mussels, resulting in a fitness cost to the host mussel. Rhodeus amarus is expanding its geographic range in Europe, hence the exposure of different freshwater mussel species to R. amarus is also rising. This expansion of contact creates potential risk to affected muss...

Despite their small size, vernal pools are hotspots for biogeochemical processes and biodiversity. To better understand their functioning, we studied the influence of vegetation (Sphagnum palustre, Molinia caerulea (L.) Moench) on organic-matter (OM) decomposition in soils, during periods of drought. OM decomposition rates were quantified by using...

European freshwater ecosystems are increasingly invaded by exotic animal and plant species. Apart from increased connectivity between previously separated watersheds, the increasing temperature of the hydrosystems favors the spread of exotic species. The freshwater fauna of Central Europe is still shaped by the cold-adapted animal assemblages resul...

Urban rivers are socioecological systems, and restored habitats may be attractive to both sensitive species and recreationists. Understanding the potential conflicts between ecological and recreational values is a critical issue for the development of a sustainable river-management plan. Habitat models are very promising tools for the ecological ev...

Fluctuations of temperature and water levels are the two main drivers of aquatic life in river floodplain ecosystems. The large Middle Paraná River floodplain exhibits marked seasons and important interannual hydrological changes. Using a three-factor-based approach (fish reproductive traits, hydroclimatic conditions, and floodplain recruitment pat...

We describe the gill anatomy of Margaritifera auricularia, including a histological analysis of the marsupium, its brooding capacity and the length of the maturation process, providing information on the hitherto unknown reproductive strategy of French populations. Ova and developing embryos from the Charente and Creuse river populations were found...

The increase in minimum flows has rarely been considered to mitigate the ecological impact of hydroelectric power plants because it requires a site-specific design and expensive long-term monitoring procedure to identify the most beneficial scenario. This study presents a model-based method to estimate, within the model constraints, the most sustai...

The critically endangered Giant Freshwater Pearl Mussel Margaritifera auricularia was presumed extinct before its rediscovery in Spain in 1985 and France in 2000. Since then, numerous surveys have been set up to search for living populations in France and Spain. This article presents an up-to-date account of species distribution based on available...

River restoration (RR) is widely practiced in both rural and urban contexts by combining various goals and measures. The theoretical discourse on RR not yet adequately reflects this breadth of restoration practice. In this study, we investigated 110 French RR projects implemented between 1980 and 2015. We analyzed projects considering eight key des...

The European water governance took a decisive turn with the formulation of the Water Framework Directive (WFD), which demands the restoration of all water bodies that did not achieve sufficient ecological status. Urban rivers are particularly impaired by human activities and their restorations are motivated by multiple ecological and societal drive...

The diversity of riverscapes. Scientific, planning and management issues. Établie en 2014 auprès de l’Université François Rabelais de Tours, en partenariat avec l’Université d’Angers et la Mission Val de Loire, la Chaire UNESCO « Fleuves et patrimoine/River Culture », est un dispositif académique qui vise à favoriser les collaborations scientifique...

To explore temporal variation in trophic relationships of benthic invertebrates in the Middle Paraná River floodplain, we performed stable isotopes analysis (SIA) in two lakes with contrasting morphologies during both dry and flooding periods. Lake 1 is permanently connected, large and deep with a narrow aquatic–terrestrial transition zone (ATTZ),...

We introduce here the term “River Culture” to delineate an eco-social approach to mitigate the biological and cultural diversity crisis in riverscapes. It is based on the insight that current environmental change endangers both, biological and cultural diversities in rivers and their basins, and those activities to improve ecosystem functions, biod...

This chapter focuses on invertebrates of seasonal floodplains of large neotropical rivers. These huge wetlands are characterized by an annual monomodal flood pulse with extensive wet-and-dry phases that act as a strong selective agent on life-cycle strategies and physiological adaptations of resident biota. Invertebrates play an important role in t...

Functional classification of animals is necessary to enhance the predictive power of food web models. However, while there is a large database for functional classification of benthic invertebrates (Functional Feeding Groups, FFG) in the temperate zone, the attribution of individual species of riverine invertebrates is still in its infancies in the...

Location of study lakes in the Middle Paraná River. The Aquatic Terrestrial Transition Zone (ATTZ) is represented with striped areas. Supplementary material 1

The State of Mato Grosso in Brazil has undergone intensive land use changes over the past decades. Native ecosystems have been converted into agrosystems for the production of cash crops and cattle. The Brazilian Forest Code advocates full protection of specifically sensitive habitats, and it also safeguards a fixed percentage of native vegetation...