Amélie Truchy

French National Institute for Agriculture, Food, and Environment (INRAE) | INRAE · Department of Waters

Rivers form meta‐ecosystems, in which disturbance and connectivity control biodiversity, ecosystem functioning and their interactions across the river network, but also across connected instream and riparian ecosystems. This aquatic–terrestrial linkage is modified by drying, a disturbance that also naturally fragments river networks and thereby mod...

Leaf litter decomposition is a significant ecosystem process for streams' energy provisioning, while species‐specific decomposition rates often form a continuum from slow to fast decomposing species allowing for resources' availability to stream consumers over a longer time period after leaf fall. Leaf litter mixtures in streams typically comprise...

Intermittent rivers and ephemeral streams are the world's dominant type of river ecosystem and are becoming more common because of global change. However, the inclusion of intermittent rivers and ephemeral streams in water policies and management plans remains largely limited because monitoring schemes and tools are designed for perennial rivers. I...

Fine particulate organic matter (FPOM) is an important basal resource in stream ecosystems for deposit- and filter-feeding macroinvertebrates (collectively ‘particle feeders’). Microplastics (MP) share many characteristics with FPOM (e.g. size range, surface area to volume ratios) and are potentially consumed by particle feeders. Accordingly, MP co...

Disturbance and connectivity control biodiversity, ecosystem functioning and their interactions across connected aquatic and terrestrial ecosystems, that form a meta-ecosystem. In rivers, detrital organic matter (OM) is transported across terrestrial-aquatic boundaries and along the river network and decomposed on the way by diverse communities of...

The decomposition of allochthonous organic matter, such as leaves, is a crucial ecosystem process in low-order streams. Microbial communities, including fungi and bacteria, colonise allochthonous organic material, break up large molecules and increase the nutritional value for macroinvertebrates. Environmental variables are known to affect microbia...

Rivers that do not flow year-round are the predominant type of running waters on Earth. Despite a burgeoning literature on natural flow intermittence (NFI), knowledge about the hydrological causes and ecological effects of human-induced, anthropogenic flow intermittence (AFI) remains limited. NFI and AFI could generate contrasting hydrological and...

In these times of strong pressure on aquatic ecosystems and water resources due to climate change and water abstraction, intermittent rivers and ephemeral streams (IRES) (rivers that periodically cease to flow and/or dry) have become valuable assets. Indeed, not only do they supply water but they also offer services for humanity. Despite a growing...

Ecosystem functioning and community structure are recognized as key components of ecosystem integrity, but comprehensive, standardized studies of the responses of both structural and functional indicators to different types of anthropogenic pressures remain rare. Consequently, we lack an empirical basis for (i) identifying when monitoring ecosystem...

River networks are among Earth’s most threatened hot-spots of biodiversity and provide key ecosystem services (e.g., supply drinking water and food, climate regulation) essential to sustaining human well-being. Climate change and increased human water use are causing more rivers and streams to dry, with devastating impacts on biodiversity and ecosy...

Riparian zones form the interface between stream and terrestrial ecosystems and play a key role through their vegetation structure in determining stream biodiversity, ecosystem functioning and regulating human impacts, such as warming, nutrient enrichment and sedimentation. We assessed how differing riparian vegetation types influence the structura...

Community responses to and recovery from disturbances depend on local (e.g. presence of refuges) and regional (connectivity to recolonization sources) factors. Droughts are becoming more frequent in boreal regions, and are likely to constitute a severe disturbance for boreal stream communities where organisms largely lack adaptations to such hydrol...

Chapter 5 from the Intermittent rivers and ephemeral streams: what water managers need to know. Technical report – Cost ACTION CA 15113

In a nutshell: ▪ There is a variety of benefits that IRES provide to our societies, from the provision of materials such as water and timber, to iconic species, the regulation of biogeochemical cycles, and space for cultural manifestation and as a corridor for both wild and herded animals. ▪ Drying and rewetting processes, timing and duration of...

Ongoing climate change is increasing the occurrence and intensity of drought episodes worldwide, including in boreal regions not previously regarded as drought prone, and where the impacts of drought remain poorly understood. Ecological connectivity is one factor that might influence community structure and ecosystem functioning post drought, by fa...

Context Community composition, environmental variation, and spatial structuring can influence ecosystem functioning, and ecosystem service delivery. While the role of space in regulating ecosystem functioning is well recognised in theory, it is rarely considered explicitly in empirical studies. Objectives We evaluated the role of spatial structuri...

Ecosystem services (ES), as an interconnection of the landscape mosaic pieces, along with temporal rivers (IRES) are an object of research for environmental planners and ecological economists, among other specialists. This study presents (i) a review on the importance of IRES and the services they can provide to agricultural landscapes; (ii) a clas...

Globally, artificial river impoundment, nutrient enrichment and biodiversity loss impair freshwater ecosystem integrity. Concurrently, beavers, ecosystem engineers recognized for their ability to construct dams and create ponds, are colonizing sites across the Holarctic after widespread extirpation in the 19th century, including areas outside their...

Stream habitat is typically patchy but movements of organisms and materials at both local and larger scales connect habitat patches one another. These fluxes may promote faster recovery of biotic assemblages and hence the processes they are associated with after disturbances. We conducted an artificial stream channel experiment in which we investig...

WATERS is a five-year research programme that started in spring 2011. The programme’s objective is to develop and improve the assessment criteria used to classify the status of Swedish coastal and inland waters in accordance with the EC Water Framework Directive (WFD). WATERS research focuses on the biological quality elements used in WFD water qua...

Hydropower accounts for 60% of Sweden’s electrical supply, with hundreds of rivers dammed across the country. However, the impacts of these dams on stream biodiversity and ecosystem processes, such as litter decomposition or algal growth, have been poorly researched. Such processes underpin key ecosystem services delivered from freshwater environme...

Final ecosystem services (i.e. services that directly benefit humanity) depend fundamentally upon the various processes, regulated by organisms, which underpin ecosystem functioning and maintain ecosystem structures. Such processes include inter alia primary productivity, detritus decomposition, pollination, soil formation, and nutrient uptake and...

Direct measurement of ecosystem process rates, such as litter decomposition, can provide an additional dimension in the bioassessment of human impacts on aquatic ecosystems. Such processes underpin key ecosystem services delivered from freshwater environments, including provision of food and clean water, and the mitigation of pollutants and toxins....

Quantification of ecosystem process rates provides an additional dimension in the bioassessment of human impacts on aquatic ecosystems. However, the responses of ecosystem processes to the linked changes in abiotic parameters, biodiversity, and community structure caused by human disturbances are poorly understood for most classes of impact. We inv...

The last decade has been one of growing research on ecosystem functioning which can be defined as the efficiency with which an ecosystem process transforms energy and nutrients and maintains ecosystem structures. Healthy ecosystem can support ecosystem services of importance for humanity, such as the provision of clean water, food and the mitigatio...