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Despite the large number of ponds scattered across the landscape, there is still insufficient recognition of their functioning. This would require the development of methods for assessing this type of aquatic ecosystem, based on their environmental specificity. Even though conditions are potentially homogenic in small and shallow water bodies, macrophytes divide the area into diverse microhabitats. Therefore, we hypothesized that the type of habitat (the open water vs. various macrophytes) may have a considerable structuring effect on functional groups, such as life-forms (pelagic and littoral) or trophic-associated rotifers, confirming their great suitability for environmental studies. Sixty three ponds, with 136 sites located within the open water, helophytes and elodeids, were analysed. Eutrophic rotifers showed a similar response to environmental factors and were linked to a certain type of habitat as was the whole pelagic community, while mesotrophic rotifers, which ecologically also belong to the pelagic community, responded in the same way as the littoral community and species diversity. The first group of rotifer indices, pelagic rotifers and their eutrophic fraction prevailed in the open water of fishstock large-surfaced ponds. However, the second group consisting of littoral rotifers along with overall species diversity and mesotrophic fraction, increased concurrently with the presence of crustaceans in small-surfaced ponds overshaded by nymphaeids and pleustophytes. The presence of elodeids in ponds, particularly Ceratophyllum and Chara, with the highest complexity (plant biomass), apart from increasing the diversity and share of littoral rotifers, reduced the occurrence of eutrophic rotifers and increased that of mesotrophic ones. This confirms the viability of using certain trophic indicators for water quality prediction in ponds. While elodeids were of the greatest importance, helophytes did not impact rotifer distribution, having no indicative value for quality state assessment in ponds. We demonstrate that a functional approach, taking into account rotifer life forms (pelagic vs. littoral community), may serve as a valuable tool for environmental analyses in case of small water bodies. Rotifer indices revealed not only a prevalence towards a particular type of habitat but they also selectively chose certain species of macrophyte beds, which suggests that for conservation purposes a highly complex cover of elodeids should be maintained to improve the ecological value of ponds.

The objective of this study is to provide information on the zooplankton community and physicochemical properties of Uzungöl Lagoon. Sampling studies were performed at monthly intervals for abiotic factors and community parameters between September 2015 and August 2016. The variations of zooplankton community were estimated using Shannon-Weiner diversity (H'), Pielou evenness (J), species richness (S), frequency, and dominancy indices. The relationship between environmental variables and community parameters were analyzed with Pearson's correlation test and redundancy analysis (RDA). During the study, 39 species, most of which belonged to Rotifera, were recorded. The quantitative analysis indicated that most important fraction of zooplankton were small-sized rotifers with low filtration rate. The species belonging to Rotifera reached their most important numerical maximum in February. Dominant organisms in the zooplankton community were found to be Filinia terminalis, Keratella quadrata, Brachionus angularis, and Polyarthra vulgaris. The relatively low diversity and evenness values resulted from a clear dominance of few species in the zooplankton community. Temperature had a positive effect on diversity and species richness, but increasing salinity had a negative effect on these indices. RDA biplot indicated that Anuraeopsis fissa, Hexarthra mira, Keratella tropica, and Polyarthra vulgaris were positively correlated with temperature. Additionally, Keratella cochlearis and Keratella quadrata were positively correlated with dissolved oxygen (DO) and negatively correlated with temperature. A negative correlation was found for pH with Filinia longiseta and Keratella quadrata. [ABSTRACT FROM AUTHOR]

Indices based on community structure provide a global ecological status of the biological communities but they are of limited value as early-warning indicators of contamination. Almost two decades after the Water Framework Directive (2000/60/EC) was adopted, we reviewed publications that measured biomarkers in benthic macroinvertebrates in biomonitoring programmes of fluvial systems. The focus was on studies that attempted to incorporate both biomarkers and community-based approaches in the evaluation of the ecological status of rivers and streams. Overall, the data showed that biomarker measurements in benthic macroinvertebrate species can offer complementary information on the factors threatening these communities. This information is particularly useful for water authorities, in order to take actions before a system collapses into a state from which recovery is difficult or impossible. Gaps in need to be addressed for rapid and efficient implementation of biomarkers in benthic macroinvertebrates in routine wide-scale monitoring are discussed. In particular, site-specific baselines have to be defined, taking into account the influence of biotic and abiotic factors on these biochemical responses. Further studies, including different biomarkers, environmental stressors, macroinvertebrate taxa and river types, will provide crucial information on how to establish adequate biomarker strategies to indicate future ecological damage. [ABSTRACT FROM AUTHOR]

Aim The impact of multiple stressors on biodiversity is one of the most pressing questions in ecology and biodiversity conservation. Here we critically assess how often and efficiently two main drivers of global change have been simultaneously integrated into research, with the aim of providing practical solutions for better integration in the future. We focus on the integration of climate change (CC) and land-use change (LUC) when studying changes in species distributions. Location Global. Methods We analysed the peer-reviewed literature on the effects of CC and LUC on observed changes in species distributions, i.e. including species range and abundance, between 2000 and 2014. Results Studies integrating CC and LUC remain extremely scarce, which hampers our ability to develop appropriate conservation strategies. The lack of CC-LUC integration is likely to be a result of insufficient recognition of the co-occurrence of CC and LUC at all scales, covariation and interactions between CC and LUC, as well as correlations between species thermal and habitat requirements. Practical guidelines for the study of these interactive effects include considering multiple drivers and processes when designing studies, using available long-term datasets on multiple drivers, revisiting single-driver studies with additional drivers or conducting comparative studies and meta-analyses. Combining various methodological approaches, including time lags and adaptation processes, represent further avenues to improve global change science. Main conclusions Despite repeated claims for a better integration of multiple drivers, the effects of CC and LUC on species distributions and abundances have been mostly studied in isolation, which calls for a shift of standards towards more integrative global change science. The guidelines proposed here will encourage study designs that account for multiple drivers and improve our understanding of synergies or antagonisms among drivers. [ABSTRACT FROM AUTHOR]

The present study examined variables that contribute to well-being, one of the main indices of immigrants' adjustment (personal resources and community indices) among Ethiopian women who emigrated to Israel. Based on social systems theory, three levels of variables were examined: inputs (personal resources), throughputs (community indices), and outputs (well-being). Path analysis revealed interesting results that shed new light on the research model and emphasize the key role of developing leadership competence among women immigrants from Ethiopia. According to the new model, the level of inputs includes the community indices but does not include personal resources. In this analysis, leadership competence was the only community variable that correlated significantly with personal resources. No significant direct associations were found between the level of inputs (in this case, community indices) and the level of outputs (well-being). However, results showed that self-esteem mediated between leadership competence and well-being. The Discussion section of this article will highlight the importance of developing professional interventions that focus on promoting leadership competence among individuals, groups, and communities, as well as on enhancing personal resources. [ABSTRACT FROM AUTHOR]

Actinomycetes, Bacillus subtilis, and Bacillus thuringiensis were isolated from municipal-solid waste (MSW) compost, and different microbial liquid filtrates (MLF) were prepared. Sterile culture media with no microbes were used as their controls. The effects of MLF on soil nematode communities were examined in pot-grown Festuca arundinacea Schreb. Fifteen genera of nematodes in background soil were identified, of which Helicotylenchus and Rotylenchus were dominant. The inoculation of MLF strongly affected the abundance and community structure of soil nematodes. Compared with their controls, lower total nematode numbers following MLF incorporation were found. Actinomycetes inoculation changed community structure of soil nematodes, transforming the dominant genera from Helicotylenchus and Rotylenchus into Cephalobus, Chiloplacus, and Aphelenchus. Actinomycetes incorporation resulted in a significant decrease of plant-parasitic nematodes relative to control pots. Only plant-parasitic and omnivorous-predatory nematodes were found in treatments following B. subtilis inoculation, and Helicotylenchus, Rotylenchus were dominant genera with relative abundance of 76.2% and 14.3%, respectively. Although the dominant genera were still Helicotylenchus and Rotylenchus, B. thuringiensis inoculation led to a marked decrease in populations of plant-parasitic nematodes and an increase in populations of fungivorous and bacterivorous nematodes relative to control. Shannon's diversity index ( H′), evenness index ( J′), richness index ( SR), and Wasilewska index ( WI) in pots treated with actinomycetes and B. thuringiensis filtrates were significantly higher than those of their controls, whereas significant lower dominance index (λ) in actinomycetes and B. thuringiensis treatments was observed than their controls. Plant growth was improved in the treatments inoculated with three microbes. The findings highlight that actinomycetes can most effectively suppress plant-parasitic nematodes, increase community diversity, evenness, and richness, thus improving soil environment for turf growth. [ABSTRACT FROM AUTHOR]

In eight European study sites (in Spain, Ireland, Netherlands, Germany, Poland, Estonia and Sweden), abundance of breeding farmland bird territories was obtained from 500 × 500 m survey plots (30 per area, N = 240) using the mapping method. Two analyses were performed: (I) a Canonical Correspondence Analysis of species abundance in relation to geographical location and variables measuring agricultural intensification at field and farm level to identify significant intensification variables and to estimate the fractions of total variance in bird abundance explained by geography and agricultural intensification; (II) several taxonomic and functional community indices were built and analysed using GLM in relation to the intensification variables found significant in the CCA. The geographical location of study sites alone explains nearly one fifth (19.5%) of total variation in species abundance. The fraction of variance explained by agricultural intensification alone is much smaller (4.3%), although significant. The intersection explains nearly two fifths (37.8%) of variance in species abundance. Community indices are negatively affected by correlates of intensification like farm size and yield, whereas correlates of habitat availability and quality have positive effects on taxonomic and functional diversity of assemblages. Most of the purely geographical variation in farmland bird assemblage composition is associated to Mediterranean steppe species, reflecting the bio-geographical singularity of that assemblage and reinforcing the need to preserve this community. Taxonomic and functional diversity of farmland bird communities are negatively affected by agricultural intensification and positively affected by increasing farmland habitat availability and quality. [ABSTRACT FROM AUTHOR]

Abstract: The impacts of waste crumb rubber soil amendment on nematode abundance, community structure and soil characteristics were studied in pot grown Lolium perenne L. Three treatments, no crumb rubber (CK), 10% and 15% crumb rubber (CR), were arranged in a randomized complete design. After 3 months’ turfgrass growth, soil nematodes were extracted and identified to genus level, and populations of total, bacterivorous, fungivorous, omnivorous, predatory and plant parasite nematodes were counted. Genus diversity, richness, evenness, plant parasite index (PPI) and maturity index (MI) were calculated to compare nematode community structure. Thirteen genera of soil nematodes in all treatments were identified, of which Helicotylenchus was dominant. Crumb rubber incorporation significantly decreased plant parasite and omnivorous nematode populations, but increased the abundance of predatory nematodes. However, fungivorous and bacterivorous nematode populations were not significantly affected by crumb rubber amendment. Pots treated with 15% CR had the lowest number of plant parasite, omnivorous nematodes and the highest number of fungivorous, predatory nematodes. Shannon''s diversity index (H′), evenness (J′), PPI and PPI/MI reduced in pots receiving crumb rubber, whereas dominace (λ) and maturity index (MI) increased in crumb rubber treatments. In addition, CR application decreased soil bulk density and pH value, but increased soil moisture. [Copyright &y& Elsevier]

Sense of community (SOC) has been one of the most studied topics in community psychology. However, no empirical study to date has investigated SOC in Hong Kong and its relations with community characteristics and residents’ psychological well-being. A representative sample of 941 Hong Kong Chinese based on a randomized household survey was conducted in all 18 districts in Hong Kong. Results of hierarchical linear modeling indicated that SOC was not associated with sociodemographic indicators on both the individual-level (i.e., gender, age, family income, education level, type of residence, and area-to-capita ratio of residence) and the community-level (i.e., proportion of individuals with tertiary education, median family income, ownership of residence, population density, and resident stability). SOC was negatively related to daily hassles and positively with social support and quality of life. Conceptualization of SOC in Hong Kong was discussed. [ABSTRACT FROM AUTHOR]

Nematode community analysis may provide a useful tool to quantify soil health. Nematode communities were monitored for 5 years during a 12-year period in the sustainable agriculture farming systems (SAFS) project at UC Davis, where conventional (CONV), low-input (LOW) and organic (ORG) management treatments were compared. After the completion of three 4-year crop rotation cycles, a uniform crop of oats was grown in 2001. The composition of the nematode genera was different from year to year, but there were significant management effects on genus composition in each year, with the CONV treatment being significantly different from the LOW and ORG treatments. Important contributors to the differences in genus composition among treatments were plant parasitic nematodes. Nematode community indices (enrichment (EI), basal (BI) and channel (CI) indices) of the CONV treatment differed from those of the ORG and LOW treatments in 1993, 1994, 1995 and 2000, but not in 2001. The difference in structure index (SI) among management treatments was significant in 1995 and 2000. EI and SI were generally lower, and BI and CI higher in CONV than in LOW and ORG treatments. There were significant crop effects on the community indices throughout the years. Even in 2001, there was a residual effect of the crop grown in 2000 on most nematode community indices. Differences in EI, BI and CI among crops were consistent, while those in SI were not. Meloidogyne javanica (Treub) Chitwood, juveniles added to various soil samples were reduced by 68% in soil where nematode trapping fungi had been added and which had low BI (12) and low CI (20) values. Soil from SAFS plots with a high BI (47) and high CI (70) after 1 year of oats and ploughing, suppressed root knot juveniles much less. There were significant negative correlations between BI and root knot nematode (RKN) suppression (−0.72) and between CI and RKN suppression (−0.74). Thus, BI and CI appeared to be most valuable as indicators for long-term effects of management on nematode suppression. However, BI and SI may be more suitable as general indicators for the health status of a soil, since CI can be high in highly disturbed agro-ecosystems as well as in undisturbed natural ecosystems. A high BI would indicate poor ecosystem health, while a high SI would indicate a well-regulated, healthy ecosystem. For agricultural soils the presence of large populations of plant parasitic nematodes forms an additional indication of poor ecosystem health, as natural regulation is limited in this case. [Copyright &y& Elsevier]

The 2009–2010 "El Niño"-Southern Oscillation (ENSO) event was characterized by a warm-phase leading to a five-fold increase in the Río de la Plata river flow and an associated change in trophic state because of organic enrichment. We analyzed the biotic response of benthic communities to such an increased trophic state during this ENSO event using community and biotic indices (diversity indices and AMBI). Polychaeta exhibited the highest richness and second the most abundant values while the small gastropod Heleobia australis was the most abundant and frequent species. An increase in richness and diversity of Polychaeta was associated to a concomitant increase of RdlP flow and the organic enrichment of the macrobenthic species. Community indices (richness and diversity) showed variability at both temporal and spatial scale but only AMBI exhibited spatial variability without significant differences between contrasting environmental conditions (ENOS phases). [Display omitted] • An ENSO event promoted changes in chemical and biotic sediment variables. • Variability in salinity and protein sediment content were reflected in macrobenthic community indices. • AMBI was useful to infer spatial differences between zones with different environmental quality. • Richness, diversity and AMBI are recommended for the Montevideo Coastal zone environmental monitoring programs. [ABSTRACT FROM AUTHOR]

The performance of three approaches for macrobenthic classification in distinguishing communities subjected to different environmental conditions was compared: i) the traditional species-based approach; ii) a tolerance-based approach according to ecological groups of the AMBI index; and iii) a character-based approach using biological traits. We used a hierarchical sampling design including three progressively smaller spatial scales, considering that the environmental degradation influence benthic communities at the larger spatial scale. Despite small-scale spatial variations, all approaches performed similarly, distinguishing eutrophic from non-eutrophic benthic communities as they varied significantly at the larger scale, corresponding to the scale at which human induced changes act. Our results suggest that all three methodological approaches could be used as operational criteria to assess estuarine environmental quality, and despite more meaningful, there is still a degree of subjectivity in functional approaches, associated to the lack of more detailed information on macrofaunal life-cycles and levels of tolerance to disturbance. • We tested three macrobenthic-based approaches in estuaries subjected to eutrophication. • All faunal grouping approaches detected anthropogenic changes despite small scale variability. • The approaches could be used as operational criteria for management along South Atlantic coast. [ABSTRACT FROM AUTHOR]

Plant roots are inhabited by a diversity of microorganisms known to be key drivers of plant growth and health. Although the rules governing root microbiota assembly have been investigated and the importance of abiotic determinants highlighted, the consequences of the biotic context of the plant community have often been overlooked. We tested the hypothesis that the abundance of species in a given plant neighborhood could leave a fingerprint on its root-endophytic fungal community, ultimately impacting its biomass. Outdoor experimental mesocosms, comprising a range of floristic compositions and spatially mapped plant distributions, were monitored for 2y. Medicago truncatula was used as trap-plant and grown under standardized conditions on soil samples collected in the mesocosms. The root-endophytic fungal community of M. truncatula was described by amplicon mass sequencing and M. truncatula performance was also assessed. The richness and evenness of M. truncatula 's root-endophytic fungal community were explained by the small-scale plant neighborhood of the soil samples. For instance, the occurrence of Brachypodium pinnatum in the neighborhood induced higher and lower richness of Sordariomycetes and Glomeromycetes, respectively, whereas Holcus mollis decreased the OTU evenness of the entire mycobiota. These changes in fungal clade OTU richness and evenness were related to modifications in the biomass of M. truncatula. These results indicate that a given plant endophytic fungal community is determined in part by the neighboring plants. Considering that changes in endophytic fungal community are correlated with the plant biomass, this suggests that plant-plant interactions (i.e. competition, facilitation) impacting plant biomass can be mediated by endophytic fungal community changes. [ABSTRACT FROM AUTHOR]