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The olive fruit fly Bactrocera oleae (Rossi, 1790) poses a significant threat to oliviculture worldwide, despite extensive chemical control measures. The susceptibility of olive (Olea europaea L.) to this pest varies among cultivars, with fruit size being a key factor of interest, as it can be assessed using non-destructive automated technologies. In this study, we investigated the oviposition preferences of the olive fruit fly in six Italian olive cultivars, tracking fertile and sterile punctures in relation to the diametric growth of the drupe. Additionally, we assessed the genetic diversity among cultivars using SSR markers, aiming to uncover a potential correlation between variation in the genetic diversity patterns and infestation levels. The results revealed that the relationship between fruit size and infestation level is non-linear and varies across different cultivars. The co-inertia analysis (COIA) performed on the genetic and infestation datasets revealed possible shared patterns of diversity and relationships between the two datasets. This study emphasizes the complex and diverse nature of the interaction between the olive fruit fly and its host, underscoring the importance of comprehending non-linear relationships to develop accurate genotypic-specific predictions and models. [ABSTRACT FROM AUTHOR]

In this study, we examined the influence of soil variables (pH, total potassium (TK), available potassium (AK), total nitrogen (TN), total phosphorus (TP), available phosphorus (AP), cation exchange capacity , soil organic carbon (SOC), moisture content (Moisture), subsurface temperature (TEMP), and metal concentrations (Cd, Pb, Cu, and Zn)) on the distribution patterns of earthworm ecological categories, diversity, and species composition in Hebei Province, North China. In total, 535 earthworms were collected from 18 sites, and belonged to three families, six genera, and ten species. Drawida gisti (17.9 inds m−2, 37.8%) and Amynthas hupeiensis (9.3 inds m−2, 39.5%) were the dominant species. The Co-inertia analysis ranking results among the soil factors and earthworms indicated that SOC and AK enhanced the earthworm density (R = 0.76**, p < 0.01; R = 0.77**, p < 0.01). The distribution patterns of epigeic and endogeic species appeared to follow an opposite trend to soil variables (SOC, K, and Moisture) under different agricultural management practices. Anecic species differed considerably from the other ecotypes, and were unaffected by the soil properties (except for TEMP) and metals. The redundancy analysis results showed that the abovementioned dominant species (D. gisti and A. hupeiensis) belong to ecological groups with different propensities for the soil factors (K, P, and SOC). Overall, the soil metal (Cd and Pb) concentrations were not the dominant regressors for the earthworm assemblage. Soil properties (K and SOC) were the main factors affecting earthworm density, category, and species dominance in the study areas. [ABSTRACT FROM AUTHOR]

The olive fruit fly Bactrocera oleae (Rossi, 1790) poses a significant threat to oliviculture worldwide, despite extensive chemical control measures. The susceptibility of olive (Olea europaea L.) to this pest varies among cultivars, with fruit size being a key factor of interest, as it can be assessed using non-destructive automated technologies. In this study, we investigated the oviposition preferences of the olive fruit fly in six Italian olive cultivars, tracking fertile and sterile punctures in relation to the diametric growth of the drupe. Additionally, we assessed the genetic diversity among cultivars using SSR markers, aiming to uncover a potential correlation between variation in the genetic diversity patterns and infestation levels. The results revealed that the relationship between fruit size and infestation level is non-linear and varies across different cultivars. The co-inertia analysis (COIA) performed on the genetic and infestation datasets revealed possible shared patterns of diversity and relationships between the two datasets. This study emphasizes the complex and diverse nature of the interaction between the olive fruit fly and its host, underscoring the importance of comprehending non-linear relationships to develop accurate genotypic-specific predictions and models.

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]

Besides their important ecological role in flowing waters, blackflies (Diptera: Simuliidae) may pose medical and veterinary risks. For seventeen months, we surveyed the blackflies of ten localities across the Aures Mountains, in the Saharan Atlas, Algeria, and recorded eight taxa (i.e. species, species groups or species complexes). High altitude sites were dominated by the Simulium ornatum (Meigen, 1818) group, whereas sites located on the southern slope of the Aures Mountains were occupied by the eurytopic Simulium velutinum (Santos Abreu, 1922) complex and the thermophilic, pollutant-tolerant Simulium ruficorne Macquart, 1838 ‘A’ morphotype. Co-inertia analysis was used to determine the relationship between a species’ abundance and habitat types. The co-inertia analysis revealed a likely co-structure between blackfly assemblages and measured environmental descriptors (water temperature, conductivity, current velocity, bed width, etc.) in sampled habitats. This confirmed the importance of altitude as a driver of blackfly distribution. Our results also showed that there has been an increase in anthropogenic pressures on the vulnerable freshwater biota of the Aures Mountains. [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]

Trawling pressure and environmental changes may affect the composition of fish assemblages. Our knowledge on large spatio-temporal patterns of demersal fish composition remains incomplete for the Mediterranean Sea. We investigated (1) the spatio-temporal stability of demersal assemblages, (2) the relationships between these assemblages and potential structuring factors (trawling pressure and environmental conditions) in order to assess the dynamic of the assemblage structure at the scale of the northern Mediterranean Sea. We analysed a dataset of 18062 hauls from 10 to 800 m depth performed annually during the last two decades across 17 Geographical Sub-Areas (GSAs) (MEDITS program). A multi-table analysis (STATICO-CoA) evidenced a strong inter-GSAs stability in the organization of assemblages, with specificities for some GSAs. The most stable structuring factors were linked to combined gradients of chlorophyll a, phytoplancton carbon biomass and temperature, inversely correlated with depth, salinity and nutrient gradients (axis 1 of the STATICO-CoA compromise, 93.74% of the total variability). A common pattern linking the distribution of species to these environmental gradients was evidenced for most of the 17 GSAs. Estimate of trawling pressure showed a minor role in the organization of the assemblages for the spatial scale and years investigated (axis 2, 4.67%).

Fish diversity and assemblage patterns in relation to habitat characteristics were investigated in the Petchaburi River, Thailand, during the dry season and early rainy season (January to June 2019). Sampling was carried out in four stations on the river, from the upper portion downstream to the Kaeng Krachan Reservoir. A total of 5,416 individual fish were sampled from 31 species. Mean abundance was 44.6±40.1 fish per 100 m², mean species richness was 10.8±4.0, mean Shannon diversity H' index was 1.75±0.44, and mean evenness J' index was 0.32±0.05. These indices increased from upstream to downstream. They also tended to increase from the onset to middle of the dry season, then decreased at the onset of the rainy season. Co-inertia analysis indicated habitat preference in some species; for example, Tor tambroides was positively correlated with macrophytes, shade, bedrock, and boulders, whereas Aperioptus delphax preferred high velocity flows in dense vegetation, with sand and cobble substrates. The assemblage patterns were analyzed both for Q-mode (station×month) and R-mode (species) clustering, and habitat specificity of some species was clearly observed. Results of this study are timely useful for resource management and conservation, regarding that the Kaeng Krachan National Park has just been announced as UNESCO Natural World Heritage site in July 2021. [ABSTRACT FROM AUTHOR]

The stoneflies of the Maghreb (Tunisia, Algeria and Morocco) are characterized by high endemicity but their ecology remains poorly known. We have surveyed the stonefly assemblages of northeastern Algeria mountain streams, a relatively unstudied region, and attempted to identify through co-inertia analysis the environmental correlates of their distribution. Species richness varied from nine taxa in the most species-rich localities to a single taxon in some anthropogenically impacted localities. Results indicated a significant co-structure between ecological descriptors and stonefly distribution and frequency of occurence. Mountain stream stonefly assemblages differed according to water conductivity, altitude, anthropogenic impacts, and spring proximity. The frequent occurrence of Afroperlodes lecerfi, Brachyptera auberti and Tyrrenoleuctra tangerina was indicative of high altitude, intermittent streams whereas Amphinemura berthelemy, Eoperla ochracea and Leuctra sartori favoured permanent, low-altitude headwaters. Conversely, Leuctra cf. vaillanti seemed to tolerate low altitude sites characterized by high water conductivity, large bed width and fast flow. This study also highlights the diversity of the Maghrebian endemic or microendemic stoneflies harbored by relict lotic streams and their sensitivity towards anthropogenic stressors. [ABSTRACT FROM AUTHOR]

Despite their ecological and socio-economic significance, the black fly communities of Algerian hydrosystems have been understudied. The simuliid fauna of relict mountain streams of northeastern Algeria was sampled at 24 localities in two distinct and relatively uncharted watersheds. Species richness in the El Kala Highlands varied from eight taxa in the most species-rich localities to the virtual absence of any taxon in some localities. Species richness also mirrored the hydroperiod of most localities and reached its peak in late winter/early spring. Co-inertia analysis indicated a significant co-structure between environmental descriptors and black fly assemblages, suggesting a strong influence of the habitat templet on aquatic insect community structure. A comparison with an additional survey of 23 localities spread across northern Algeria suggests distinct black fly assemblages characterizing the El Kala Highlands.

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]

Species delimitation in Cactaceae is a challenging task due to the proliferation of species and subspecies names. Echinocereus pulchellus occurs across a wide geographical range in Mexico and presents numerous polymorphisms. The species complex has been considered to comprise five subspecies. In the present work, we analyze morphological variation across the E. pulchellus complex to establish the taxonomic limits of the complex, to delimit taxa within it, and to determine whether morphological variation is associated with climate variables. Multivariate analyses of 50 morphological characters were conducting in a sample of ten populations representing all five of the previously recognized subspecies of the E. pulchellus complex. The results support the recognition of four distinct species, one of which contains two subspecies, and necessitate three new combinations: Echinocereus acanthosetus,E. sharpii, and E. weinbergii subsp. venustus. Six vegetative and two floral characters define the morphological limits between taxa. Correlation with climate variables was detected in the populations of E. weinbergii. [ABSTRACT FROM AUTHOR]

This paper presents results of comprehensive studies of saline rivers in the arid Elton Lake region based on hydrobiological surveys of planktonic and bottom communities. Two tables representing the species structure of communities and produced on the basis of survey data collected on 13 river sites in 2013 and 2018, including data on the abundance of hydrobionts belonging to 94 different taxonomic groups of macrozoobenthos, meiobenthos, and zooplankton, have been compared. The co-inertia analysis has identified a high statistical consistency of the data matrices determined by objective spatial distribution patterns of aquatic organisms. A randomization test was applied to the Procrustean correlation coefficient, and it showed that the conjugacy of the two species structures in the space of latent variables is statistically significant (p = 0.00026). Concurrently, a change trend was noted for the taxonomic composition of some surveyed communities affected by dynamic abiotic factors. The relationship between the taxonomic structure of hydrobionts and the combination of 30 abiotic environmental factors measured in the course of the hydrobiological and hydrochemical monitoring of the studied river sites was analyzed. Using canonical correlation analysis and the technique of projection to latent structures, a complex of ordination diagrams has been produced permitting the identification of specific "environmental niches" for each species group, including certain sets of biotope characteristics. A significant mutual correlation between the planktonic and bottom communities has been established. This correlation indicates close interrelations between these communities determined both by biotic interactions and by mutually consistent reactions to changes in aquatic environmental factors. [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]

Summary: The distribution and community structure of plant-parasitic nematodes associated with betel (Piper betle) vine and their relationship with soil chemical properties were investigated in four major growing regions of West Bengal, India. Ordinary kriging method was applied to infer the patterns of spatial distribution of major plant-parasitic nematodes across the growing regions. Meloidogyne and Rotylenchulus were found to be the most abundant genera in betel vine crops in all growing regions. Co-inertia analysis between soil properties and nematode abundance indicated that soil chemical characters significantly affect abundances of plant-parasitic nematodes. The type of betel vine crop (sweet and bitter) also has a significant effect on the abundance of plant-parasitic nematodes, with the highest abundance of Meloidogyne reported from the bitter type of betel crop. Spatial distribution depicted a higher abundance of Meloidogyne throughout the North Bengal growing region. Root-knot and reniform nematodes are two important plant-parasitic nematodes of betel vine that might cause economic yield loss to the growers in West Bengal. [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]

The abundance and diversity of macroinvertebrates are closely related, among other features, with the nutrient content of the soil. In order to analyse this relationship under agroforestry arrangements of the Colombian Andean Amazon (Caquetá), a completely random plot design with three repetitions was used, being the treatment of the agroforestry arrangements: AB = Abarco (Cariniana pyriformis Miers); CH = Caucho (Hevea brasiliensis (Willd. ex A. Juss.) Müll. Arg.); PA = Paricá (Schizolobium amazonicum Huber); y HU = Huito (Genipa Americana L.). In each arrangement monoliths of 25 x 25 x 30 cm of depth according ISO 23611-5 to quantify the macrofauna and soil samples for physical-chemical characterization were taken. The relationship among edaphic properties and the macrofauna in the different agroforestry arrangements was determined by a Co-inertia analysis. The highest abundance of macrofauna was found in the AB arrangement (945 ± 382 individuals/m2) and the minimum 487 ± 80 (individuals /m2). The total richness was 13 taxa, being the PA arrangement the one with the highest richness (6.6 ± 0.8) and the AB arrangement with the lowest richness (4.8 ± 0.8). A significant correlation (Co-inertia analysis: RV = 0.13, P <0.05, Monte Carlo test) was observed, this proved the response of the macrofauna to the properties of the soil. Specifically, a negative effect of aluminium on the abundance of Coleoptera was found, as well as some positive relationships between organic carbon and the abundance of earthworms and phosphorus with the abundance of termites. [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]

“Mixed Profiling” (MP) is a descriptive profiling combining a pre-established list of descriptors scored by all tasters and the possibility for each panellist to add free descriptors. All the descriptors, free or not, are rated on an intensity scale. The aim is to improve the reliability of wine characterisation in a professional context. Quantitative Descriptive Analysis® provides a fine characterisation while free-choice profiling is a more holistic method that is easier to implement with professionals. In general, professionals are not trained together and evaluate wines using pre-defined descriptors. MP aims to combine the power of the two methods. It is compared to a classical profiling (CP) largely performed in a wine professional context that uses a pre-defined list of descriptors. Ten red wines were evaluated by two distinct panels of wine professionals without prior common training. Performances of the panel were verified using variance analysis and the results of both sensory methodologies were compared using a multi-block method. The results reveal that MP avoids the omission of a specific sensory characteristic and provides a complete sensory characterisation of products in a short time. [ABSTRACT FROM AUTHOR]

With the practice of conservation agriculture (CA) soil water and nutrient dynamics are modified by the presence of a mulch of crop residues and by reduced or no-tillage. These alterations may have impacts on crop yields. The crop growth model DSSAT (Decision Support Systems for Agrotechnology Transfer) has recently been modified and used to simulate these impacts on crop growth and yield. In this study, we applied DSSAT to a long-term experiment with maize ( Zea mays L.) grown under contrasting tillage and residue management practices in Monze, Southern Province of Zambia. The aim was (1) to assess the capability of DSSAT in simulating crop responses to mulching and no-tillage, and (2) to understand the sensitivity of DSSAT model output to input parameters, with special attention to the determinants of the model response to the practice of CA. The model was first parameterized and calibrated for the tillage treatment (CP) of the experiment, and then run for the CA treatment by removing tillage and applying a mulch of crop residues in the model. In order to reproduce observed maize yields under the CP versus CA treatment, optimal root development in the model was restricted to the upper 22 cm soil layer in the CP treatment, while roots could optimally develop to 100 cm depth under CA. The normalized RMSE values between observed and simulated maize phenology and total above ground biomass and grain yield indicated that the CA treatment was equally well simulated as the CP treatment, for which the model was calibrated. A global sensitivity analysis using co-inertia analysis was performed to describe the DSSAT model response to 32 model input parameters and crop management factors. Phenological cultivar parameters were the most influential model parameters. This analysis also demonstrated that in DSSAT mulching primarily affects the surface soil organic carbon content and secondly the total soil moisture content, since it is negatively correlated with simulated soil water evaporation and run-off. The correlations between the input parameters or crop management factors and the output variables were stable over a wide range of seasonal rainfall conditions. A local sensitivity analysis of simulated maize yield to three key parameters for the simulation of the CA practice revealed that DSSAT responds to mulching particularly when rooting depth is restricted, i.e., when water is a critical limiting crop growth factor. The results of this study demonstrate that DSSAT can be used to simulate crop responses to CA, in particular through simulated mulching effects on the soil water balance, but other, often site-specific, factors that are not modeled by DSSAT, such as plough pan formation under CP or improved soil structure under CA, may need to be considered in the model parameterization to reproduce the observed crop yield effects of CA versus CP. [ABSTRACT FROM AUTHOR]

In many regions of Europe, large-scale socio-economic changes have led to the abandonment of rural activities and a gradual takeover of natural vegetation. It is important to assess the relative positive and negative effects of land abandonment on particular areas where the low-intensity farming is no longer socially or economically viable in order to quantify the potential conservation costs and benefits of a rewilding as a land-use management policy. During the period 2000-2010, we studied the land-use/land-cover changes in an abandoned mountain landscape (Galicia, NW Spain) and evaluated the effects on breeding bird occurrence and distribution. For this purpose, we analysed remotely sensed data-derived maps in combination with data obtained from bird censuses carried out in 2000 and 2010 at both landscape and census plot scale. The results revealed a gradient of change from bare ground and open shrubland to closed shrubland and woodland. Thirteen shrubland and forest bird species showed a significant increase (including species of conservation concern such as Turtle Dove, Dartford Warbler and Western Bonelli's Warbler), while four ecotone and open-habitat species (e.g. Red-backed Shrike) showed a significant negative trend. In conclusion, rewilding appears to have overall positive effects on biodiversity and should be considered by policy makers as alternative land-use strategy in marginal mountain areas, particularly if they have been historically affected by wildfires. Fire management aimed at favouring the creation of small burned areas in progressively closed landscapes derived from rewilding may be a complementary alternative to maintain open habitats in these areas. [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]

This paper is about the problem of the treatment of ordinal qualitative variables in co-inertia analysis. In the literature, there are different proposals based on the application of known statistical techniques to quantify ordinal variables. Here we propose to use a new procedure for the coding considering the empirical distributions of the variables involved in the analysis. We present an application to a real dataset, comparing the results obtained with the different kinds of quantification. [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]

In order to investigate the symmetrical relationships between several sets of variables, or regress one or more quantitative response variables on a set of variables of different nature, it is well known that it is necessary to transform non-quantitative variables in such a way that they can be analyzed together with the others measured on an interval scale. This paper suggests a proposal to cope with the problem of the treatment of ordinal qualitative variables in Co-Inertia(-PLS) Analysis. In the literature there are different proposals based on the application of known statistical techniques to quantify ordinal variables. The approach consists in quantifying each non-quantitative variable according to the empirical distributions of the variables involved in the analysis assuming the presence of a continuous underlying variable for each ordinal indicator. [ABSTRACT FROM AUTHOR]

Understanding environmental factors related to exotic earthworm distributions across invasion stages (i.e., introduction, colonization, regional spread) is critical for assessing long-term impacts on previously earthworm-free forests. Studies following earthworm community establishment in North America, however, remain limited. We address this by characterizing historical and current exotic earthworm distributions in a regionally representative aspen-dominated forest, where their presence was first documented in the early 1900s. We map historic earthworm distribution records in a 360-km2 area surrounding our current study site, and re-analyze data collected nearly 60 years ago to inform contemporary associations between species densities and environmental factors. Field surveys were conducted over two years (2008-2010) using 10 permanent plots, with concurrent measurements of environmental 'effect factors' determined by large-scale ecosystem processes (leaf litter inputs, soil physical properties, soil C and N content), and environmental 'response factors' likely impacted by earthworm activity over short time scales (annual litter mass loss and soil isotopic values). Present-day communities included five exotic species with varying densities: Lumbricus rubellus ≥ Lumbricus terrestris >> Dendrobaena octaedra ≥ Aporrectodea spp. (Aporrectodea trapezoides + Aporrectodea caliginosa). These species were also present in the landscape in the early to mid-1900s though shifts in species composition, particularly the movement of L. terrestris into upland forest soils, were evident. Over two years, earthworm community composition did not show strong temporal or spatial trends characteristic of incipient invasions. However, species-specific associations with environmental factors were observed: L. terrestris and L. rubellus densities were positively associated with soil C and N content, Acer rubrum (red maple) inputs, and soil moisture; and were negatively associated with Pinus strobus (white pine) inputs. D. octaedra, and Aporrectodea spp. densities were positively associated with % sand; and negatively associated with plot-to-road distance. Soil moisture and texture were significant drivers of earthworm species abundance in historical surveys, though associations with soil C were only evident for Aporrectodea spp. Contemporary associations between earthworm species and soil C and N content suggest greater nutrient limitation in upland forest soils, while the importance of plot-to-road distance suggests the persistence of dispersal limitation and repeated introductions as a mechanism maintaining population densities. Species-specific associations with environmental response variables were also observed, where: surface soil δ13C depletion was associated with Aporrectodea spp. and D. octaedra biomass; δ15N enrichment was associated with total earthworm biomass, but negatively associated with L. rubellus biomass; and increased leaf litter mass loss was associated with L. terrestris and juvenile biomass. As soil C and N pools were not higher in plots with higher earthworm biomass, these results suggest earthworm activity may influence soil nutrient cycling by decreasing turnover times of nutrient pools over the long-term. Our results characterize exotic earthworm distributions at scales relevant to forest ecosystem processes, and allow for future extrapolation of laboratory and controlled field studies assessing impacts on soil nutrient cycling across northern temperate forests. [ABSTRACT FROM AUTHOR]

Aim of this paper is to introduce Gower and Hand's biplot procedures within the Co-Inertia Analysis. Predictive biplots can be considered a good choice for interpretation purposes while interpretative ones are very useful to classify new samples not used for the construction of the main co-inertia axes. [ABSTRACT FROM AUTHOR]

Abstract: Partial Least Squares (PLS) methods are particularly suited to the analysis of relationships between measures of brain activity and of behavior or experimental design. In neuroimaging, PLS refers to two related methods: (1) symmetric PLS or Partial Least Squares Correlation (PLSC), and (2) asymmetric PLS or Partial Least Squares Regression (PLSR). The most popular (by far) version of PLS for neuroimaging is PLSC. It exists in several varieties based on the type of data that are related to brain activity: behavior PLSC analyzes the relationship between brain activity and behavioral data, task PLSC analyzes how brain activity relates to pre-defined categories or experimental design, seed PLSC analyzes the pattern of connectivity between brain regions, and multi-block or multi-table PLSC integrates one or more of these varieties in a common analysis. PLSR, in contrast to PLSC, is a predictive technique which, typically, predicts behavior (or design) from brain activity. For both PLS methods, statistical inferences are implemented using cross-validation techniques to identify significant patterns of voxel activation. This paper presents both PLS methods and illustrates them with small numerical examples and typical applications in neuroimaging. [Copyright &y& Elsevier]

Abstract: By using an original framework involving complementary statistical approaches, we investigated the environmental attitudes of 6379 pre-service and in-service teachers in 16 countries of Europe and its neighbourhood. To test hypotheses about the nature of environmental attitudes, we examined the variation across groups of individuals (between-class analysis), investigated the independent effects of several candidate explanatory factors (orthogonal analysis), and finally inspected potential relationships between conceptions on a variety of topics (co-inertia analysis). In accordance with the 2-MEV model of Wiseman and Bogner, we identified two independent dimensions that are, respectively, “Preservation” and “Utilization” oriented. Although attitudes mainly differed across countries with respect to the Utilization dimension, as the influence of socio-economic background seemed to be prominent, the 2-dimensional structure was robust in varying contexts, and teacher discipline was a consistent source of variation in attitudes within countries. [Copyright &y& Elsevier]

Abstract: Changes in soil N mineralization pathways occurring along a full rotation cycle have received little attention to date, while tree uptake for N may change during forest ageing. The aims of this study were (i) to characterize changes in potential net N mineralization and potential net nitrification within organic layers and the topsoil (organo-mineral horizon) along a 100-year chronosequence for a temperate oak–hornbeam forest and (ii) to reveal covariances between potential net N mineralization pathways and the properties of the humic epipedon (defined as the sum of organic layers and topsoil). For that purpose, a space-for-time substitution procedure and aerobic laboratory incubation method for 28 days at 28°C in the dark were used. In addition, acetylene and captan were used to discriminate between autotrophic and heterotrophic (bacterial and/or fungal) nitrification. Several humic epipedon properties were determined, e.g. pH, exchangeable cation concentrations, effective cation exchange capacity, total C and N, dissolved organic C and N, fungal and microbial biomass N. Potential net N mineralization and nitrification pathways changed greatly along the mixed forest chronosequence. Potential net N mineralization in the organic layers increased with stand maturation whereas potential net nitrification in the topsoil decreased significantly. Selective inhibitors revealed changes in nitrification pathways along the chronosequence, i.e. potential net nitrification was autotrophic in the topsoil while it was mainly heterotrophic within the organic layers. In the organic layer, potential net nitrification was autotrophic at the onset of the chronosequence while it appeared heterotrophic during the aggradation phase and finally fungal in mature stands. A Co-Inertia Analysis was used to reveal covariances between N mineralization pathways and humic epipedon properties. The analysis showed two functional temporal shifts within N cycling along the chronosequence, one probably controlled by organic matter quality and high competition for available N resulting in the autotrophic versus heterotrophic nitrification shift in the organic layers and one mainly controlled by (i) fine organic matter abundance, allowing high N mineralization in the organic layers and (ii) acidity inhibited autotrophic nitrification in the topsoil. [Copyright &y& Elsevier]

Abstract: This study focused on the potential of using soil microbial biomass, enzyme and mineralization activities involved in organic C, N and P turnover, to evaluate the quality of a subtropical agricultural soil affected by long-term acid metal stress. Fractions of C, N and P involved in soil organic matter, microbial biomass and mineralization processes were estimated. Total enzyme activity (FDA) and eight hydrolase activities (xylanase, amylase, β-glucosidase, invertase, N-acteyl-glucosaminidase, urease, alkaline and acid phosphatases) in different decomposition stages of organic C, N and P were selected to characterize the soil functional diversity. These biological datasets were compared with soil metal variables (total contents and free and ligand-complexed ions of Cu, Pb, Zn, Cd, Al and Mn), using principal component analyses, co-inertia and discriminant analyses. The multiple statistics indicate that the metal variables were significantly related with not only general biological factors, but also respective datasets of biomass, enzyme activities and mineralization rates (all P <0.001). In general, metal variables were inversely related to parameters and indices of microbial biomass C, N and P, FDA and C-related polysaccharidase and heterosidase activities, and P mineralization. As comparison, metal variables exhibited positive relationships with parameters and indices of N-related N-acteyl-glucosaminidase, urease, ammonification, total N mineralization and metabolic quotient, compared with inhibited nitrification. Specifically, free and complexed metal cations showed higher bioavailability than total contents in most cases. Cu, Pb, Al and Mn had different ecotoxicological impacts than Cd and Zn did. Stepwise regression models demonstrated that metal variables are key stress factors, but most of them excluded soil pH. Furthermore, spatial distribution in land uses and of sampling sites clearly separated the soil samples in these models (P <0.001). We conclude that such a statistical analysis of microbiological and biochemical indices can provide a reliable and comprehensive indication of changes in soil quality and organic nutrient cycling, after exposure to long-term acid metal stress. [Copyright &y& Elsevier]

Abstract: With the increase of laboratory facilities, molecular phylogenies are playing a predominant role in evolutionary analyses. However, understanding the evolution of morphological traits remains essential for a comprehensive view of the evolution of a group. Here we present a new approach based on co-inertia analysis for identifying characters which variations are dependent to the phylogeny, a prerequisite for analyzing the evolution of characters. Our approach has the advantage of treating the full data set at once, including qualitative and quantitative variables. It provides a graphical output giving the contribution of each variable to the co-structure, allowing a direct discrimination among phylogenetically dependent and independent variables. We have implemented this approach in deciphering the evolution of morphological traits in a highly specialized group of Neotropical catfishes: the Loricariinae. We have first inferred a molecular phylogeny of this group based on the 12S and 16S mitochondrial genes. The resulting phylogeny indicated that the subtribe Harttiini was restricted to the single genus Harttia, and within the subtribe Loricariini, two sister subtribes were distinguished, Sturisomina (new subtribe), and Loricariina. Among Loricariina, the morphological groups Loricariichthys and Loricaria + Pseudohemiodon were confirmed. The co-inertia analysis highlighted a strong relationship between the morphological and the genetic data sets, and identified three quantitative and eight qualitative variables linked to the phylogeny. The evolution of quantitative variables was assessed using the orthogram method and showed a major punctual event in the evolution of the number of caudal-fin rays, and a more gradual pattern of evolution of the number of teeth along the phylogeny. The evolution of qualitative variables was inferred using ancestral states reconstructions and highlighted parallel patterns of evolution in characters linked to the mouth, suggesting co-evolution of the traits for adapting to divergent substrates. [Copyright &y& Elsevier]

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.

We investigated the relationships between the composition and structure of macroinvertebrate communities and some environmental variables over a year in four basins of the Etueffont landfill leachate (Belfort, France) using co-inertia analysis. Culicidae larvae were the dominant macroinvertebrate group in the studied basins, contributing to 87% of the total zoobenthos density, followed by Corixidae (8.8%), Chironomids (2.5%) and other larvae (each <1%). The lowest density of chironomid larvae was recorded in the first basin which is used as a discharge system for the leachate produced by the landfill. In basin 4, however, the Baetidae, Orthocladiinae ( Orthocladius spp., Chaetocladius spp. and Isocladius spp.) and Tanypodinae ( Psectrotanypus spp.) developed favoured by low levels in ammonia, COD, BOD, EC, metals and high oxygen concentrations. The co-inertia analysis illustrated both temporal and spatial variabilities in the basins and revealed a strong relationship between environmental conditions and benthic macroinvertebrates assemblages. This ordination technique showed that the chironomid community structure might be used successfully to differentiate between sites with different levels and types of pollution. [ABSTRACT FROM AUTHOR]

Abstract: This project studied how meso- and macro-zooplankton communities (composition, abundance, and biomass) in the Senegal River Estuary varied in time and space depending on hydro-biological factors and human action. Samples were taken approximately every 45days, from January to December 2003, at 3 sampling stations where the estuary was subject to different marine and continental influences. Temperature, salinity, fluorescence and oxygen were measured using a Seabird probe (SBE 19). Meso- and macro-zooplankton were collected using standard nets (200μm and 500μm mesh sizes respectively), towed horizontally at the surface and at a depth of 3m–5m. The study showed a marked seasonal variation which clearly influenced the structure and distribution of meso-zooplankton and macro-zooplankton communities. During the low water period (November–June) the marine influence prevailed, decreasing from the river mouth to the upstream part of the estuary near the Diama anti-salt dam. Zooplankton was abundant, containing mainly marine organisms and a few euryhaline species (i.e. Acartia clausi) which colonized the estuary. During the high water period (July–October) the estuary was mainly under the continental influence and the impact of the annual flood. Zooplankton was less abundant but more diversified than during the low water season and was dominated by freshwater species which entered the estuary through the Diama Dam. By comparison with previous works, this study showed significant changes in the abundance of zooplankton and the types of community since the Diama Dam came into operation in 1985. The results also showed the initial effects on the pelagic ecosystem of a channel opened in October 2003 in the middle part of the estuary. [Copyright &y& Elsevier]

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]