SYLVAIN MASTRORILLO | Université de Toulouse III Paul Sabatier (original) (raw)
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Papers by SYLVAIN MASTRORILLO
Belgian Journal of Zoology, Feb 1, 2004
Hydrobiologia, Jul 31, 2005
Ambio a Journal of the Human Environment, Sep 1, 2005
We assessed the influence of environmental variables (elevation, stream order, distance from sour... more We assessed the influence of environmental variables (elevation, stream order, distance from source, catchment area, slope, stream width, and fish species richness) on the co-occurrence patterns of the minnow, the stone loach, and the gudgeon at the stream system scale. A total of 474 sites were classified according to the seven variables using the Self-Organizing Map (neural network), and three clusters were detected (k-means algorithm). The frequency of the various fish co-occurrence patterns was calculated for each cluster, and general linear modeling was used to specify the conditions that predict the occurrence of each species. Piedmont streams were more likely to support coexisting gudgeon and minnow populations because of higher probabilities of occurrence for both species. The higher co-occurrence frequency for the three species together in headwater streams resulted from lower occurrence frequencies in gudgeon and minnow. Focusing on areas that favor the co-occurrence of species may enhance the effectiveness of conservation projects.
Archives of Environmental Contamination and Toxicology, Nov 1, 1997
Biological Conservation
Our ability to demonstrate statistical patterns of invasion by non-native species will determine ... more Our ability to demonstrate statistical patterns of invasion by non-native species will determine the success of future management projects. We investigated the suitability of self-organizing maps (SOM, neural network) for patterning habitat invasion by exotic fish species at the regional scale (Southwest France), using a binary dataset of species occurrences. The SOM visualization can be used as an analytical tool to bring out relationships between sample locations and biological variables, but in addition the weight of each species in the output of the SOM can be interpreted as its occurrence probability in various geographic areas. After training the SOM with fish presence/absence data, the k-means algorithm helped to derive three major clusters of sites (headwater, montane, and plain areas). Each cluster was divided into two subsets of sites according to non-native fish, because assemblage compositions delineated different geological areas: Pyrenees Mountains, Massif Central Moun...
Science of The Total Environment, 2014
Science of The Total Environment, 2012
Journal of Fish Biology, 2005
ABSTRACT Spatial patterns in the combinations of biological traits of fish communities were studi... more ABSTRACT Spatial patterns in the combinations of biological traits of fish communities were studied in the Garonne River system (57 000 km2, south-west France). Fish species assemblages were recorded at 554 sampling sites, and the biological traits of species were described using a fuzzy-coding method. A co-inertia analysis of species distributions and biological traits identified some spatial patterns of species trait combinations. Fish species richness progressively increased from up- to downstream sections, and the longitudinal patterns of fish assemblages partitioned the river into clear biogeographic areas, such as the brown trout Salmo trutta(headwater streams), the grayling Thymallus thymallus, the barbel Barbus barbus and the bream Abramis brama zones (most downstream sections), which fitted with Huet's well-known zonation for western European rivers. Only a few biological traits, chiefly related to life-history attributes, significantly influenced the observed fish distributions. Fecundity, potential size, maximum age and reproductive factor increased from headwater to plain reaches. As a theoretical framework for assessing and predicting the functional organization of stream fish communities, spatial variations in species traits can be related to habitat conditions, thus providing explicit spatial schemes that may be useful to the design of both scientific studies and river management.
International Review of Hydrobiology, 2005
... of good biological quality (see the fish database at http://www.fishbase.org/), eg, having sa... more ... of good biological quality (see the fish database at http://www.fishbase.org/), eg, having salmonid fish and polluosensitive insects (Ephemeroptera, Plecoptera and Trichop-tera). Many factors, closely related to the destruction of physical and hydraulic stream habi-tats by man ...
International Review of Hydrobiology, 2004
Belgian Journal of Zoology, Feb 1, 2004
Hydrobiologia, Jul 31, 2005
Ambio a Journal of the Human Environment, Sep 1, 2005
We assessed the influence of environmental variables (elevation, stream order, distance from sour... more We assessed the influence of environmental variables (elevation, stream order, distance from source, catchment area, slope, stream width, and fish species richness) on the co-occurrence patterns of the minnow, the stone loach, and the gudgeon at the stream system scale. A total of 474 sites were classified according to the seven variables using the Self-Organizing Map (neural network), and three clusters were detected (k-means algorithm). The frequency of the various fish co-occurrence patterns was calculated for each cluster, and general linear modeling was used to specify the conditions that predict the occurrence of each species. Piedmont streams were more likely to support coexisting gudgeon and minnow populations because of higher probabilities of occurrence for both species. The higher co-occurrence frequency for the three species together in headwater streams resulted from lower occurrence frequencies in gudgeon and minnow. Focusing on areas that favor the co-occurrence of species may enhance the effectiveness of conservation projects.
Archives of Environmental Contamination and Toxicology, Nov 1, 1997
Biological Conservation
Our ability to demonstrate statistical patterns of invasion by non-native species will determine ... more Our ability to demonstrate statistical patterns of invasion by non-native species will determine the success of future management projects. We investigated the suitability of self-organizing maps (SOM, neural network) for patterning habitat invasion by exotic fish species at the regional scale (Southwest France), using a binary dataset of species occurrences. The SOM visualization can be used as an analytical tool to bring out relationships between sample locations and biological variables, but in addition the weight of each species in the output of the SOM can be interpreted as its occurrence probability in various geographic areas. After training the SOM with fish presence/absence data, the k-means algorithm helped to derive three major clusters of sites (headwater, montane, and plain areas). Each cluster was divided into two subsets of sites according to non-native fish, because assemblage compositions delineated different geological areas: Pyrenees Mountains, Massif Central Moun...
Science of The Total Environment, 2014
Science of The Total Environment, 2012
Journal of Fish Biology, 2005
ABSTRACT Spatial patterns in the combinations of biological traits of fish communities were studi... more ABSTRACT Spatial patterns in the combinations of biological traits of fish communities were studied in the Garonne River system (57 000 km2, south-west France). Fish species assemblages were recorded at 554 sampling sites, and the biological traits of species were described using a fuzzy-coding method. A co-inertia analysis of species distributions and biological traits identified some spatial patterns of species trait combinations. Fish species richness progressively increased from up- to downstream sections, and the longitudinal patterns of fish assemblages partitioned the river into clear biogeographic areas, such as the brown trout Salmo trutta(headwater streams), the grayling Thymallus thymallus, the barbel Barbus barbus and the bream Abramis brama zones (most downstream sections), which fitted with Huet's well-known zonation for western European rivers. Only a few biological traits, chiefly related to life-history attributes, significantly influenced the observed fish distributions. Fecundity, potential size, maximum age and reproductive factor increased from headwater to plain reaches. As a theoretical framework for assessing and predicting the functional organization of stream fish communities, spatial variations in species traits can be related to habitat conditions, thus providing explicit spatial schemes that may be useful to the design of both scientific studies and river management.
International Review of Hydrobiology, 2005
... of good biological quality (see the fish database at http://www.fishbase.org/), eg, having sa... more ... of good biological quality (see the fish database at http://www.fishbase.org/), eg, having salmonid fish and polluosensitive insects (Ephemeroptera, Plecoptera and Trichop-tera). Many factors, closely related to the destruction of physical and hydraulic stream habi-tats by man ...
International Review of Hydrobiology, 2004