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Biodiversity is a multifaceted concept for which the functional component, that influences many aspects of ecosystem functioning, remains difficult to characterise. In several taxa, many studies rely on morphological traits as proxies of species ecological attributes. However, the extent to which morphology provides a good surrogate of ecological traits has rarely been acknowledged.Here, we used morphological and ecological trait databases to test whether morphological traits are linked to ecological traits and can be used to assess various biodiversity facets in 254 stream fish communities across France.We firstly computed co‐inertia analyses to test the association between morphological and ecological traits related to either habitat use, feeding or life‐history strategies. We then computed a suite of diversity indices to investigate the relationship between morphological and ecological indices.We found a strong association between morphological and ecological traits, and significant relationships between diversity indices computed on morphological and ecological traits. However, these relationships varied according to the index and type of ecological traits, with the strongest relationship observed with traits related to habitat use.Although these results highlight that the use of morphological data is a promising way to understand ecological diversity, they also reveal that the choice of diversity index and the type of ecological traits targeted are particularly important and need to be taken into consideration. [ABSTRACT FROM AUTHOR]

Data on Maghrebian mayfly communities are scarce and fragmentary, but evidence of alterations of the North African riverine landscape depleting the freshwater biota is rapidly mounting.In contrast to the overexploited lowlands, the highlands of north‐eastern Algeria are hotspots of freshwater biodiversity and the last refugia to micro‐endemics, North African endemics, and Eurosiberian relicts.The mayflies of relict mountain streams of north‐eastern Algeria were investigated and 20 species or taxa in five families were recorded. Two species of the genus Habrophlebia and one species of Centroptilum are new to science, whereas two Rhithrogena species are new to Algeria, including the Numidian endemic Rhithrogena sartorii.Co‐inertia analysis suggested a highly significant co‐structure between mayfly assemblages and habitats defined by altitude, flow velocity, bed width, water depth, and water conductivity. In addition, a Poisson generalized linear model indicated a strong positive relationship between species richness and water depth and a weaker negative one with bed width (stream size). The results are congruent with the hypothesis that habitat provides the templet that drives mayfly communities, and they support the use of mayflies as bioindicators in the implementation of monitoring schemes to assess the ecological integrity of Maghrebian freshwater biodiversity hotspots.The upstream part of the Kebir‐East river basin is subjected to forest fires, pollution, and flow alteration, whereas the downstream part, which includes the vast Mekhada marsh, is increasingly fragmented and invaded by alien fish species. Conservation efforts focusing on the management of Oued Kebir‐East, a transboundary Maghrebian river, and the restoration of the Mekhada marsh, a Ramsar site, need to be launched during the United Nations Decade on Ecosystem Restoration (2021–2030). [ABSTRACT FROM AUTHOR]

Communities across trophic levels, and the functional roles they play, are vital for the sustained provision of ecosystem services. In forest systems, diversification of overstorey composition has been shown to be a key driver of biodiversity, but its influence on across‐trophic level relationships remains scarcely known. Species across trophic levels in varied overstorey compositions are also differentially susceptible to fragmentation context. We hypothesise that fragmentation will disrupt community relationships associated with particular overstorey compositions.We test this hypothesis using a tree diversity research platform across 53 deciduous woodland plots in central Belgium. We estimate species' abundances within nine, generally taxonomic, community groups across trophic levels: understorey vegetation; leaf miners and gall formers; woodlice, millipedes; carabid beetles, harvestmen, spiders, birds, bats. We use multiple co‐inertia analyses to examine how taxonomic and trophic role community matrices covary across gradients of overstorey composition, via three different tree species diversification pathways, and fragmentation.For all trophic role groups, across all plots, there was at least one significant pairwise comparison. Apart from comparisons involving bats, there was at least one significant pairwise correlation between taxonomic groups too. These results indicate correlated community matrices across trophic levels. Overstorey composition related to community tightness, that is, the level of co‐ordinated change among taxonomic and/or trophic role groups as revealed by multiple co‐inertia analyses. Notably, diversifying woodlands of beech Fagus sylvatica or red oak Quercus rubra with pedunculate oak Quercus robur correlated with increased taxonomic community tightness. Diversifying pedunculate oak forest stands with other overstorey species related to unchanged community tightness. Evidence was lacking for fragmentation affecting community tightness, singly or by interacting with overstorey composition.Synthesis. Overall, changing tree species composition and fragmentation level affected across‐trophic level community relationships differently. Yet, we demonstrated a clear signal that diversifying monoculture stands with particular species correlated with greater community tightness, and co‐ordinated change among sets of community groups, across trophic levels and regardless of fragmentation context. We postulate that having tighter community relationships suggests that measures to improve biodiversity at one trophic level (i.e. trees) could affect other groups, and their associated roles, in a co‐ordinated manner. [ABSTRACT FROM AUTHOR]

Community composition of freshwater prokaryotes and protists varies through time. Few studies contemporarily investigate temporal variation of these freshwater communities for more than 1 year. We compared the temporal patterns of prokaryotes and protists in three distinct habitats for 4 years (2014–2017) in Lake Tovel, a cold‐water lake. This lake showed a marked temperature increase in 2017 linked to altered precipitation patterns. We investigated whether microbial communities reflected this change across habitats and whether changes occurred at the same time and to the same extent. Furthermore, we tested the concept of hydrological year emphasizing the ecological effect of water renewal on communities for its explanatory power of community changes. Microbe diversity was assessed by Illumina sequencing of the V3–V4 hypervariable region of the 16S rRNA gene and 18S rRNA gene, and we applied co‐inertia analysis and asymmetric eigenvector maps modelling to infer synchrony and temporal patterns of prokaryotes and protists. When considering community composition, microbes were invariable in synchrony across habitats and indicated a temporal gradient linked to decreasing precipitation; however, when looking at temporal patterns, the extent of synchrony was reduced. Small‐scale patterns were similar across habitats and microbes and linked to seasonally varying environmental variables, while large‐scale patterns were different and partially linked to an ecosystem change as indicated by increasing water transparency and temperature and decreasing dissolved oxygen. Our advanced statistical approach outlined the multifaceted aspect of synchrony when linked to community composition and temporal patterns. [ABSTRACT FROM AUTHOR]

Sustainability indicators make it possible to clearly and effectively show the general public the position of different countries with respect to sustainability, to assist governments in decision‐making concerning social, environmental, and economic strategies, and to approve plans and tactics. Sustainability is now an important global issue. So many institutions are facing the challenge of building new mathematical models and developing algorithms that can confirm that we are making progress towards a more sustainable society. Given the current dearth of such methods, we thought it would be valuable to develop a new system for use in the study of sustainability, a system that will help to explain the effects of each country, describing sustainability through the use of several indicators. The Sustainable Society Index is used in the present research for the period 2006–2012. The co‐Tucker3 method is used to describe interactions between the rows, columns, and repetitions of two sequences of matrices, by reducing their dimensionality, that is, the number of elements in them. Plots are used to visualise differences or similarities in the data, for example, groups of countries that score differently on some indicators during some years, relationships between indicators, and temporal trends. Thus, our methodology makes it possible to deduce relationships among countries and temporal trends based on sustainability indicator data. [ABSTRACT FROM AUTHOR]

Abstract: Temperate forests across Europe and eastern North America have become denser since the 1950s due to less intensive forest management and global environmental changes such as nitrogen deposition and climate warming. Denser tree canopies result in lower light availability at the forest floor. This shade may buffer the effects of nitrogen deposition and climate warming on understorey plant communities. We conducted an innovative in situ field experiment to study the responses of co‐occurring soil microbial and understorey plant communities to nitrogen addition, enhanced light availability and experimental warming in a full‐factorial design. We determined the effects of multiple environmental drivers and their interactions on the soil microbial and understorey plant communities, and assessed to what extent the soil microbial and understorey plant communities covary. High light led to lower biomass of the soil microbes (analysed by phospholipid fatty acids), but the soil microbial structure, i.e. the ratio of fungal biomass to bacterial biomass, was not affected by light availability. The composition of the soil bacterial community (analysed by high‐throughput sequencing) was affected by both light availability and warming (and their interaction), but not by nitrogen addition. Yet, the number of unique operational taxonomic units was higher in plots with nitrogen addition, and there were significant interactive effects of light and nitrogen addition. Light availability also determined the composition of the plant community; no effects of nitrogen addition and warming were observed. The soil bacterial and plant communities were co‐structured, and light availability explained a large part of the variance of this co‐structure. We provide robust evidence for the key role of light in affecting both the soil microbial and plant communities in forest understoreys. Our results advocate for more multifactor global change experiments that investigate the mechanism underlying the (in) direct effects of light on the plant–soil continuum in forests. A plain language summary is available for this article. [ABSTRACT FROM AUTHOR]

The aim of this study is first to establish whether any relationships exist between countries' environmental performance, governance and socioeconomic characteristics and whether it is possible to classify countries according to these relationships. To achieve these objectives we used the 10 policy categories of the 2012 EPI and some external characteristics - control of corruption, rule of law, government effectiveness, regulatory quality, voice and accountability, political stability, population, population density and GDP per capita - since they have been previously used in the literature and demonstrated to be related to the EPI. We confront the problem from a multivariate perspective, using co-inertia analysis (COIA), a multivariate statistical method that allows us to directly relate both sets of variables measured in the same countries. The main results from the empirical analysis show that governance indicators and per capita GDP are strongly and directly related to the EPI policy categories concerning environmental effects on human beings, forestry and biodiversity and habitat, and that most European countries and North America present high scores in all of these variables. In contrast, these governance indicators are inversely related to agriculture, climate change, fisheries and the effects that air pollution has on nature, and the majority of countries in Africa, South America and Asia perform better in these political categories but with lower governance rates. The effect of water on nature and political stability covariate positively and both relate negatively to the social variables. Copyright © 2015 John Wiley & Sons, Ltd and ERP Environment [ABSTRACT FROM AUTHOR]

Comparisons of agricultural and natural ecosystems reveal the magnitude of the effects of agricultural practices on the diversity and abundance of soil nematodes. Consequently, there is the need for testing ecological hypotheses, specifically with regard to nematode ecology, in natural and agricultural soils to seek strategies for biological control and environmental monitoring. We studied soil nematode assemblages and soil physical attributes of five soil layers (0-10, 10-20, 20-30, 30-40 and 40-50 cm) from sugarcane plantations and forest remnants in the sugarcane zone of Pernambuco State, Brazil. Structure and composition of the nematode assemblage and soil properties differed between forest and sugarcane soils, even in the same locality. The soil bulk density and the abundance of all nematodes and the diversity of plant-parasitic nematodes were greater whereas soil porosity, soil respiration and abundance of predator nematodes were smaller in sugarcane than in forest areas. We suggest that sugarcane management practices result in changes in the soil properties and concomitantly alter the composition and structure of the nematode assemblages. Co-inertia analysis indicated that others environmental factors also might be affecting the nematofauna. [ABSTRACT FROM AUTHOR]

The article investigates the water quality of the River Yamuna in the Delhi stretch in India, through the identification of changes in the concentration levels of 19 physico-chemical parameters. The research indicate that vegetation plays a significant role in acting as a biological sink for mineral nutrients, thereby restoring the water quality. The restoration of the inundation pattern of floodplains may help in the reaeration of the overlying water and re-absorption of pollutants through mud/water exchanges.

Objective: This empirical study was designed to explore the role of ecological features of species in the spatial patterning of a grassland community. Location: Banks of the river Rhône in France. Material and Methods: First, we explored the spatial pattern of 29 species recorded in the community using spatial autocorrelation analysis of species cover values. Second, we then explored the relationship between the patterns found and a set of life attributes that characterized the ecological features of species for resource foraging or dispersion. Finally, we explored the spatial relationship of groups of species that shared the same ecological features using cross-correlation analysis. Results: We found a significant relationship between the spatial pattern and life attributes of the species highlighting three groups of species: (1) species characterized as competitors, reproducing by runner clonal organs and forming large, dense patches; (2) species characterized as competitive-ruderals, dispersing exclusively by seed production and forming small periodic patches; and (3) species classified as CSR, characterized by rosette morphology and short rhizomes as clonal organs without any significant spatial autocorrelation. Spatial segregation was found between group 1 and group 2 up to 14 m; no significant cross-correlation between groups 1 and 3 between 0 and 3.5 m, and association between groups 2 and 3 up to 14 m. Conclusions: These results helped to understand how species attributes (relative to stature or dispersion abilities); external factors (such as disturbance) and biotic processes (competition) interplay in structuring the plant community under study in space. [ABSTRACT FROM AUTHOR]

Although invasive alien species (IAS) are a major threat to biodiversity, human health, and economy, our understanding of the factors controlling their distribution and abundance is limited. Here, we determine how environmental factors, land use, life-history traits of the invaders, residence time, origin, and human usage interact to shape the spatial pattern of invasive alien plant species in South Africa. Relationships between the environmental factors and the extrinsic and intrinsic attributes of species were investigated using RLQ analysis, a multivariate method for relating a species-attribute table to an environmental table by way of a species presence/absence table. We then clustered species according to their position on the RLQ axes, and tested these groups for phylogenetic independence. The first three axes of the RLQ explained 99% of the variation and were strongly related to the species attributes. The clustering showed that, after accounting for environmental factors, the spatial pattern of IAS in South Africa was driven by human uses, life forms, and reproductive traits. The seven clusters of species strongly reflected geographical distribution, but also intrinsic species attributes and patterns of human use. Two of the clusters, centered on the genera Acacia and Opuntia, were phylogenetically non-independent. The remaining clusters comprised species of diverse taxonomic affinities, but sharing traits facilitating invasion in particular habitats. This information is useful for assessing the extent to which the potential spread of recant introductions can be predicted by considering the interaction of their biological attributes, region of origin, and human use. [ABSTRACT FROM AUTHOR]

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 troutSalmo trutta(headwater streams), the graylingThymallus thymallus, the barbelBarbus barbusand the breamAbramis bramazones(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. [ABSTRACT FROM AUTHOR]

A new ordination method, called co-correspondence analysis, is developed to relate two types of communities (e.g., a plant community and an animal community) sampled at a common set of sites in a direct way. The method improves the simple, indirect approach of applying correspondence analysis (reciprocal averaging) to the separate species data sets and correlating the resulting ordination axes. Co-correspondence analysis maximizes the weighted covariance between weighted averaged species scores of one community and weighted averaged species scores of the other community. It thus attempts to identify the patterns that are common to both communities. Both a symmetric descriptive and an asymmetric predictive form are developed. The symmetric form relates to co-inertia analysis and the asymmetric, predictive form. to partial least-squares regression. En two examples the predictive power of co-correspondence analysis is compared with that of canonical correspondence analyses on syntaxonomic and environmental data. In the first example, carabid beetles in roadside verges are shown to be more closely related to plant species composition than to vegetation structure (biomass, height, roughness, among others), and, in the second example, bryophytes in spring meadows are shown to be more closely related to the species composition of the vascular plants than to the measured water chemistry. [ABSTRACT FROM AUTHOR]

In this paper, we present a statistical method called STATICO that can be used to analyze series of pairs of ecological tables. The objective of this method is to find the stable part in the dynamics of the relationships between the species and their environment. The treated data are a sequence of pairs of ecological tables. Each pair is made of a species abundance table (species in columns) and an environmental variables table (variables in columns). The sampling sites (in rows) must be the same for the two tables of one pair, but they may be different among the pairs. The environmental variables must be the same in all the environmental tables, and the list of species must be the same in all the species tables too, although some species may be absent from some tables (the corresponding columns will contain all zeros). From a statistical point of view, STATICO is a multitable analysis (partial triadic analysis) performed on the series of cross-tables resulting from the co-inertia analysis of each pair of tables. A small ecological example data set is analyzed and the results are discussed to show how this method can be used to extract the stable part of species-environment relationships. All computations and graphical displays can be performed with free software available on Internet. [ABSTRACT FROM AUTHOR]