References of "Monty, Arnaud"
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See detailIncreasing plant functional diversity is not the key for supporting pollinators in wildflower strips
Uyttenbroeck, Roel ULiege; Piqueray, Julien; Hatt, Séverin ULiege et al

in Agriculture, Ecosystems & Environment (2017), 249

Intensification of agriculture has been one of the major drivers for biodiversity loss in recent decades. Pollinators, which serve an important role in pollinating crops as well as wild plants, have shown ... [more ▼]

Intensification of agriculture has been one of the major drivers for biodiversity loss in recent decades. Pollinators, which serve an important role in pollinating crops as well as wild plants, have shown a decline in species richness. Flower strips can be used to support pollinators in agro-ecosystems, however the question remains as to how their design can be optimized in order to best benefit pollinators. Increasing plant species diversity has been shown to be beneficial for pollinators, and it is often suggested that functional traits are driving this relationship. Therefore, increasing plant functional diversity could be a tool to support pollinator abundance and diversity. As experimental evidence on this relationship is scarce, we developed a field study with experimental sown flower strips with four functional diversity levels, based on multiple flower traits and with equal plant species richness. We monitored vegetation development, as well as the flower-visiting pollinator community and their interaction networks with flowers. We were able to create a functional diversity gradient while controlling for plant species richness and evenness. However, in contrast to our expectations, pollinator species richness and evenness were not influenced by functional diversity, and increasing functional diversity even resulted in lower flower visitation rates. Network stability metrics showed no effect or negative relationships with functional diversity. We conclude that increasing functional diversity was not the key for supporting pollinators in wildflower strips. Our results also suggest that, for a constant amount of flower resources, increasing plant functional diversity and thus decreasing redundancy of potential pollinator feeding niches, decreases the amount of flower resources present per feeding niche. As pollinator species tended to have less overlap in their feeding niches in flower strips with increased functional diversity, this may lead to a reduction of flower resources available for pollinator species with a more specialized feeding niche. [less ▲]

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See detailGestion de la biodiversité
Monty, Arnaud ULiege

Conference (2017, August 21)

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See detailBack to America: tracking the origin of European introduced populations of Quercus rubra L.
Merceron, Nastasia; Leroy, Thibault; Chancerel, Emilie et al

in Genome = Génome (2017), 60

Abstract: Quercus rubra has been introduced in Europe since the end of the 17th century. It is widely distributed today across this continent and considered invasive in some countries. Here, we ... [more ▼]

Abstract: Quercus rubra has been introduced in Europe since the end of the 17th century. It is widely distributed today across this continent and considered invasive in some countries. Here, we investigated the distribution of genetic diversity of both native and introduced populations with the aim of tracing the origin of introduced populations. A large sampling of 883 individuals from 73 native and 38 European locations were genotyped at 69 SNPs. In the natural range, we found a continuous geographic gradient of variation with a predominant latitudinal component. We explored the existence of ancestral populations by performing Bayesian clustering analysis and found support for two or three ancestral genetic clusters. Approximate Bayesian Computations analyses based on these two or three clusters support recent extensive secondary contacts between them, suggesting that present-day continuous genetic variation resulted from recent admixture. In the introduced range, one main genetic cluster was not recovered in Europe, suggesting that source populations were preferentially located in the northern part of the natural distribution. However, our results cannot refute the introduction of populations from the southern states that did not survive in Europe. [less ▲]

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See detailNo copper required for germination of an endangered endemic species from the Katangan Copperbelt (Katanga, DR Congo): Diplolophium marthozianum
Boisson, Sylvain ULiege; Ortmans, William ULiege; Maréchal, Justine et al

in Tropical Ecology (2017), 58(1), 193-198

Two hypotheses were tested with respect to the germination of Diplolophium marthozianum, an endemic plant species of the copper-cobalt outcrops in Katanga, Democratic Republic of Congo: (1) germination of ... [more ▼]

Two hypotheses were tested with respect to the germination of Diplolophium marthozianum, an endemic plant species of the copper-cobalt outcrops in Katanga, Democratic Republic of Congo: (1) germination of copper-endemics is limited by fungal infection in the absence of pathogen control and (2) the germination success of this copper-endemic species is copper-dependent. Seed lots of twenty seeds were weighed, soaked in different disinfection treatments and then placed in a germination medium containing four distinct copper concentrations for 30 days. Seed viability was measured at the beginning and at the end of the experiment by a cut test. Final germination percentage (15.2 ± 8.2 %) and seed viability (24.2 ± 10.3 %) were not affected by copper concentration or disinfection treatments. D. marthozianum is able to germinate in a substrate without added copper, despite pervasive fungal infection. However, seed mass had a significant positive effect on seed germination suggesting that selecting the largest seeds may ensure the highest germination success in ex situ conservation programs. [less ▲]

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See detailTracking Invasive Alien Species (TrIAS): Building a data-driven framework to inform policy
Vanderhoeven, Sonia; Adriaens, Tim; Desmet, Peter et al

in Research Ideas and Outcomes (2017), 3

Imagine a future where dynamically, from year to year, we can track the progression of alien species (AS), identify emerging problem species, assess their current and future risk and timely inform policy ... [more ▼]

Imagine a future where dynamically, from year to year, we can track the progression of alien species (AS), identify emerging problem species, assess their current and future risk and timely inform policy in a seamless data-driven workflow. One that is built on open science and open data infrastructures. By using international biodiversity standards and facilities, we would ensure interoperability, repeatability and sustainability. This would make the process adaptable to future requirements in an evolving AS policy landscape both locally and internationally. In recent years, Belgium has developed decision support tools to inform invasive alien species (IAS) policy, including information systems, early warning initiatives and risk assessment protocols. However, the current workflows from biodiversity observations to IAS science and policy are slow, not easily repeatable, and their scope is often taxonomically, spatially and temporally limited. This is mainly caused by the diversity of actors involved and the closed, fragmented nature of the sources of these biodiversity data, which leads to considerable knowledge gaps for IAS research and policy. We will leverage expertise and knowledge from nine former and current BELSPO projects and initiatives: Alien Alert, Invaxen, Diars, INPLANBEL, Alien Impact, Ensis, CORDEX.be, Speedy and the Belgian Biodiversity Platform. The project will be built on two components: 1) The establishment of a data mobilization framework for AS data from diverse data sources and 2) the development of data-driven procedures for risk evaluation based on risk modelling, risk mapping and risk assessment. We will use facilities from the Global Biodiversity Information Facility (GBIF), standards from the Biodiversity Information Standards organization (TDWG) and expertise from Lifewatch to create and facilitate a systematic workflow. Alien species data will be gathered from a large set of regional, national and international initiatives, including citizen science with a wide taxonomic scope from marine, terrestrial and freshwater environments. Observation data will be funnelled in repeatable ways to GBIF. In parallel, a Belgian checklist of AS will be established, benefiting from various taxonomic and project-based checklists foreseen for GBIF publication. The combination of the observation data and the checklist will feed indicators for the identification of emerging species; their level of invasion in Belgium; changes in their invasion status and the identification of areas and species of concern that could be impacted upon by bioinvasions. Data-driven risk evaluation of identified emerging species will be supported by niche and climate modelling and consequent risk mapping using critical climatic variables for the current and projected future climate periods at high resolution. The resulting risk maps will complement risk assessments performed with the recently developed Harmonia+ protocol to assess risks posed by emergent species to biodiversity and human, plant, and animal health. The use of open data will ensure that interested stakeholders in Belgium and abroad can make use of the information we generate. The open science ensures everyone is free to adopt and adapt the workflow for different scenarios and regions. The checklist will be used at national level, but will also serve as the Belgian reference for international databases (IUCN - GRIIS, EASIN) and impact assessments (IPBES, SEBI). The workflow will be showcased through GEO BON, the Invasivesnet network and the COST Actions Alien Challenge and ParrotNet. The observations and outcomes of risk evaluations will be used to provide science-based support for the implementation of IAS policies at the regional, federal and EU levels. The publication of Belgian data and checklists on IAS is particularly timely in light of the currently ongoing EU IAS Regulation and its implementation in Belgium. By proving that automated workflows can provide rapid and repeatable production of information, we will open up this technology for other conservation assessments. [less ▲]

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See detailRemoval of acorns of the alien oak Quercus rubra on the ground by scatter-hoarding animals in Belgian forests
Merceron, Nastasia; De Langhe, Aurélie; Dubois, héloïse et al

in Biotechnologie, Agronomie, Société et Environnement = Biotechnology, Agronomy, Society and Environment (2017), 21(2), 127-130

Description of the subject. Quercus rubra L. is considered an invasive species in several European countries. However, little is known about its dispersal in the introduced range. Objectives. We ... [more ▼]

Description of the subject. Quercus rubra L. is considered an invasive species in several European countries. However, little is known about its dispersal in the introduced range. Objectives. We investigated the significance of animal dispersal of Q. rubra acorns on the ground by vertebrates in its introduced range, and identified the animal species involved. Method. During two consecutive autumns, the removal of acorns from Q. rubra and from a native oak was assessed weekly in forest sites in Belgium. We used automated detection camera traps to identify the animals that removed acorns. Results. Quercus rubra acorns were removed by wood mice (Apodemus sylvaticus L.), red quirrels (Sciurus vulgaris L.), rats (Rattus sp.), and wild boars (Sus scrofa L.). The two former are scatter-hoarding rodents and can be considered potential dispersers. Conclusions. Dispersal of Q. rubra acorns in Western Europe by scatter-hoarding animals may help the species increasingly colonize forest ecosystems [less ▲]

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See detailRemoval of northern red oak acorns by animals - supporting video
Merceron, Nastasia ULiege; Monty, Arnaud ULiege

Learning material (2017)

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See detailDo flower mixtures with high functional diversity enhance aphid predators in wildflower strips?
Hatt, Séverin ULiege; Uyttenbroeck, Roel ULiege; Chevalier Mendes Lopes, Thomas ULiege et al

in European Journal of Entomology (2017), 114

Among semi-natural elements in agricultural landscapes, wildflower strips sown at field margins or within fields represent potential habitats for the natural enemies of insect pests. As insects are ... [more ▼]

Among semi-natural elements in agricultural landscapes, wildflower strips sown at field margins or within fields represent potential habitats for the natural enemies of insect pests. As insects are sensitive to a variety of flower traits, we hypothesised that mixtures with high functional diversity attract and support a higher abundance and species richness of aphid flower visiting predators compared to mixtures with low functional diversity. During a field experiment, repeated over two years (2014 and 2015) in Gembloux (Belgium), aphid predators (i.e., lacewings, ladybeetles and hoverflies) were pan-trapped in five sown flower mixtures (including a control mixture, with three replicates of each mixture) of low to high functional diversity based on seven traits (i.e., flower colour, ultra-violet reflectance and pattern, blooming start and duration, height and flower class, primarily based on corolla morphology). In both years, flower species in the sown mixtures (i.e., sown and spontaneous flowers) were listed, and the realised functional diversity of each plot was calculated. Over the two years, an increase in functional diversity did not result in an increase in the abundance and richness of aphid predators. Moreover, ladybeetles, representing the majority of trapped predators, were more abundant in mixtures with very low or intermediary functional diversity at sowing, especially in 2014. We hypothesise that certain flower species, which were abundant in certain mixtures (and not in those exhibiting the highest functional diversity), attracted predators and were sufficiently represented to support them. Our results present novel information that could be used to the development of flower mixtures that provide effective ecosystem services, such as pest control. [less ▲]

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See detailInvasive Alien Species in HeidelbergCement’s quarries in the European Union
Monty, Arnaud ULiege

Conference (2016, December 09)

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See detailPlant functional trait diversity in wildflower strips: the key to promote pollinators in agricultural landscapes?
Uyttenbroeck, Roel ULiege; Piqueray, Julien; Monty, Arnaud ULiege

Conference (2016, October 27)

Creating wildflower strips is often suggested as a tool to support pollinator diversity in agricultural landscapes and to promote crop pollination service. The choice of the plant species to sow in flower ... [more ▼]

Creating wildflower strips is often suggested as a tool to support pollinator diversity in agricultural landscapes and to promote crop pollination service. The choice of the plant species to sow in flower strips can influence the effectivity of the strips in supporting pollinators. While it has already been shown that increasing plant species diversity is beneficial for ecosystem services, it is often suggested that plant functional traits and functional trait diversity are the key for this relationship. We created a replicated field experiment with different levels of plant functional diversity in wildflower strips in Belgium to test the effect on the flower-visiting pollinator community. We sampled plant-pollinator interaction networks during 2 years and assessed how the plant functional diversity affected the network structure. Plant functional diversity did not have a clear effect on visiting pollinator species richness, however a different interaction pattern was observed with different functional diversity level. Pollinators in wildflower strips with higher functional diversity had less overlap in their ecological niche, while network stability and robustness for secondary extinctions were not affected. We discuss implications for wildflower strip design. [less ▲]

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See detailEffects of seed traits variation on seedling performance of the invasive weed, Ambrosia artemisiifolia
Monty, Arnaud ULiege; Mahy, Grégory ULiege; Ortmans, William ULiege

Poster (2016, September 14)

Seedling performance can determine the survival of a juvenile plant and impact adult plant performance. Understanding the factors that may impact seedling performance is thus critical, especially for ... [more ▼]

Seedling performance can determine the survival of a juvenile plant and impact adult plant performance. Understanding the factors that may impact seedling performance is thus critical, especially for annuals, opportunists or invasive plant species. Seedling performance can vary among mothers or populations in response to environmental conditions or under the influence of seed traits. However, very few studies have investigated seed traits variations and their consequences on seedling performance. Specifically, the following questions have been addressed by this work: 1) How the seed traits of the invasive Ambrosia artemisiifolia L. vary among mothers and populations, as well as along the latitude; 2) How do seed traits influence seedling performance; 3) Is the influence on seedlings temperature dependent. With seeds from nine Western Europe ruderal populations, seed traits that can influence seedling development were measured. The seeds were sown into growth chambers with warmer or colder temperature treatments. During seedling growth, performance-related traits were measured. A high variability in seed traits was highlighted. Variation was determined by the mother identity and population, but not latitude. Together, the temperature, population and the identity of the mother had an effect on seedling performance. Seed traits had a relative impact on seedling performance, but this did not appear to be temperature dependent. Seedling performance exhibited a strong plastic response to the temperature, was shaped by the identity of the mother and the population, and was influenced by a number of seed traits. [less ▲]

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See detailFirst come first served: “priority effect“ benefits Ambrosia artemisiifolia L. more than other ruderal Asteraceae species
Ortmans, William ULiege; Mahy, Grégory ULiege; Monty, Arnaud ULiege

Poster (2016, September 14)

Ambrosia artemisiifolia L. (common ragweed, Asteraceae) is an invasive weed causing a health crisis in Europe, due to its highly allergenic pollen. In Western Europe the invaded range covers most of ... [more ▼]

Ambrosia artemisiifolia L. (common ragweed, Asteraceae) is an invasive weed causing a health crisis in Europe, due to its highly allergenic pollen. In Western Europe the invaded range covers most of central and southern France, and northern Italy. Northwards beyond the edge of this range, occurrence of casual population have been described for years, but these populations do not appear to become invasive, and the species does not seem to spread. This situation raises the following question: Has the invaded range reached a limit or will the species continue its invasion northwards? To answer this question, we followed two complementary approaches. First we set up an experimental garden in Belgium, 250 km north to the current invaded range, to see if the local climate allows the completion of the species reproduction cycle. Second, we performed an in situ measurement campaign in 12 population located beyond the edge, within the range but near the margin, and in the center of the invaded range. The aim of this campaign was to test whether the species had reduced plant performance towards range margins. The results showed that the species is able to establish populations with high growth rates in Belgium. Furthermore, the species expressed similar performance across the considered areas, even beyond the current invasion front. No evidence of processes constraining the invasion was found, which suggests a great potential for invasion north to the current invaded range. In this uncertain situation, awareness actions should be considered in the northern countries. [less ▲]

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See detailIs Ambrosia artemisiifolia L. able to expand its invaded range northward in Western Europe?
Ortmans, William ULiege; Mahy, Grégory ULiege; Monty, Arnaud ULiege

Conference (2016, September 13)

Ambrosia artemisiifolia L. (common ragweed, Asteraceae) is an invasive weed causing a health crisis in Europe, due to its highly allergenic pollen. In Western Europe the invaded range covers most of ... [more ▼]

Ambrosia artemisiifolia L. (common ragweed, Asteraceae) is an invasive weed causing a health crisis in Europe, due to its highly allergenic pollen. In Western Europe the invaded range covers most of central and southern France, and northern Italy. Northwards beyond the edge of this range, occurrence of casual population have been described for years, but these populations do not appear to become invasive, and the species does not seem to spread. This situation raises the following question: Has the invaded range reached a limit or will the species continue its invasion northwards? To answer this question, we followed two complementary approaches. First we set up an experimental garden in Belgium, 250 km north to the current invaded range, to see if the local climate allows the completion of the species reproduction cycle. Second, we performed an in situ measurement campaign in 12 population located beyond the edge, within the range but near the margin, and in the center of the invaded range. The aim of this campaign was to test whether the species had reduced plant performance towards range margins. The results showed that the species is able to establish populations with high growth rates in Belgium. Furthermore, the species expressed similar performance across the considered areas, even beyond the current invasion front. No evidence of processes constraining the invasion was found, which suggests a great potential for invasion north to the current invaded range. In this uncertain situation, awareness actions should be considered in the northern countries. [less ▲]

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See detailOccurrence rates of invasive plants in limestone quarries (Southern Belgium)
Pitz, Carline ULiege; Jorion, Alexis ULiege; Mahy, Grégory ULiege et al

Conference (2016, August 23)

In quarries, invasive plant species can slow down the installation of high conservation value vegetation. Successful management of invasive requires, at first, a quantitative assessment of invasion levels ... [more ▼]

In quarries, invasive plant species can slow down the installation of high conservation value vegetation. Successful management of invasive requires, at first, a quantitative assessment of invasion levels. Although European legislation has adopted an ambitious strategy against invasive species, there is still a lack of knowledge about their occurrence in quarries. The aim of this study was to evaluate occurrence rates of invasive plant species in limestone quarries throughout Wallonia (Southern Belgium) and identify high priority and emerging invasive plants for adapted management. During 2016 vegetation period, forty quarries were selected by stratified sampling, using abandoned and active quarries as strata. Within selected quarries, two-meter wide transects were established to cross all activity sectors. Transects were divided in 10x2m plots, resulting in 2% of total surface of each quarry being surveyed. Cover and number of individuals of invasive plants species were recorded in each plot. Species considered were those of Harmonia list (67 species), the reference at the Wallonia scale. More than 30 000 plots were surveyed. Results of our recent study are presented (occurrences rates by species, mean percentage cover per site). First results indicate that dominant invasive species originate from different introduction paths: (i) planted (Robinia pseudoacacia); (ii) ornamentals (Cotoneaster horizontalis) and (iii) spontaneous colonization (Senecio inaequidens) - and follow various invasion dynamics. We propose research and management methods to be directed towards limitation of top ten frequent species (e.g. Buddleia davidii, Senecio inaequidens), and to establish a detection system for the emerging invasive plants. [less ▲]

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See detailA population approach to evaluate grassland restoration - a systematic review
Harzé, Mélanie ULiege; Monty, Arnaud ULiege; Boisson, Sylvain ULiege et al

Conference (2016, August)

How do we know if restoration goals are achieved? In practice, the criteria used to evaluate the success of restoration actions are numerous and can be defined at different ecological scales, i.e. at the ... [more ▼]

How do we know if restoration goals are achieved? In practice, the criteria used to evaluate the success of restoration actions are numerous and can be defined at different ecological scales, i.e. at the population, community or ecosystem level. Most studies about restoration success monitoring assessed attributes corresponding to the community or ecosystem levels like species diversity, vegetation structure and ecological processes. Has the population approach been disregarded to evaluate restoration success? This systematic review of the literature aimed to identify how often plant population traits were used to monitor restoration of grasslands. Practically, 3133 papers were reviewed among which 1065 reported monitoring of plant species after a restoration action. Only 153 papers used a population approach and represent the core of this review. Detailed results and paper content will be presented with the aim to identify restoration protocols (with or without species addition), species of interest, population attributes and processes considered to evaluate restoration success. [less ▲]

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See detailDiaspore heteromorphism in the invasive Bromus tectorum L. (Poaceae): sterile fl orets increase dispersal propensity and distance
Monty, Arnaud ULiege; Maebe, Laura ULiege; Mahy, Grégory ULiege et al

in Flora (2016)

Within a species, the distance travelled by a particular diaspore depends on its morphology. In Poaceae, the presence of terminal sterile florets can lead to diaspore heteromorphism, which may influence ... [more ▼]

Within a species, the distance travelled by a particular diaspore depends on its morphology. In Poaceae, the presence of terminal sterile florets can lead to diaspore heteromorphism, which may influence dispersal. We tested the hypothesis that the presence of sterile florets favored dispersal in Bromus tectorum L., an invasive grass in the Western US. We used field and controlled experiments to study the dispersal of caryopses with and without sterile florets attached (respectively complex and simple diaspores), as well as pieces of inflorescence that detached from the mother plants. We considered both primary and secondary dispersal, as well as abiotic and biotic dispersal agents. The distance travelled by the diaspores and their attachment to animal fur were related to the presence and number of sterile florets. Abiotic agents moved diaspores over relatively short distances, both in terms of primary and secondary dispersal. A significant proportion of diaspores attached to fur, suggesting a potential for dispersal over longdistances. Complex diaspores were better dispersers than simple ones (and pieces of inflorescence), and this pattern was consistent across the study. However, among complex diaspores, the number of sterile florets had little or no influence. Considering primary and secondary dispersal by abiotic and biotic agents provided a general picture of the dispersal ecology of B. tectorum. For all the dispersal steps and dispersal agents we studied, the presence of sterile florets favored dispersal. These results highlight the functional significance of diaspore heteromorphism induced by floret sterility in the dispersal of Poaceae. [less ▲]

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See detailNo evidence for genetic differentiation between French and Belgian populations of the exotic tree Robinia pseudoacacia
Bouteiller, Xavier; Aikio, E; Raimbault, A et al

Poster (2016, May)

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See detailStructuration of Robinia pseudoacacia L. genetic diversity in the American natural range and derived Belgian populations
Verdu, Cindy; Daïnou, Kasso; De Thier, Olivier et al

Poster (2016, May)

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See detailMonitoring the occurrence of invasive plants in different types of natural habitats
Monty, Arnaud ULiege; Frisson, Gwenn; Delbart, Emmanuel et al

Conference (2016, April 19)

Protected areas and the Natura 2000 network are keystones of the EU nature and biodiversity policy. However, alien plants do not stop their spread at the border of protected areas and invasive plants are ... [more ▼]

Protected areas and the Natura 2000 network are keystones of the EU nature and biodiversity policy. However, alien plants do not stop their spread at the border of protected areas and invasive plants are reported to threaten many ecosystems, from aquatic and riparian areas to dry and xeric sites. The presentation summarizes three large-scale quantitative assessments of the occurrence of exotic plants in Wallonia, i.e. the southern part of Belgium. Three types of natural habitats were the focus of the assessments: i) ponds and lakes (400 sites); ii) river banks (187 sites); and iii) xeric ecosystems such dry grasslands, rocky habitats and screes (86 sites). In the three studies, sites were selected through a stratified sampling then visited. Exotic plants were recorded and their abundance assessed. Additional information about population dynamics, environmental conditions and visible impacts was recorded. Elodea spp. were the most common species in water bodies, with occurrence rates reaching 2.7%. Other aquatic alien species were found, but with an occurrence rate below 1%. Along rivers, 51 alien species were observed. Some were widespread (e.g. Impatiens glandulifera, with 17 % of linear banks invaded) whereas others were either rare or considered emergent alien species. Analyses showed that typical riparian species’ occurrence increased with the size of the watershed, indicating propagule pressure within protected areas through hydrochory. In xeric sites, the most common species were either cultivated or ornamental ones such as Juglans regia, Cotoneaster horizontalis, Prunus serotina, Robinia pseudoacacia and Buddleja davidii. The former was found in 15.1% of the visited sites. The implications of the different results, notably about emergent species, are related to the need for an effective early detection system. [less ▲]

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