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Background: Mangrove forests are highly productive ecosystems that serve as biodiversity points, containing many organisations, contributing to carbon storage, improving water quality and providing ecosystem goods and services to improve local means of subsistence. These resilient ecosystems are characterised by their morphological modification and their particular respiratory structures (pneumatophores), which allow them to proliferate in salt-rich environments. Mangroves play a crucial role in maintaining invertebrate and fishery resources, providing shelter and nutrients to a diverse range of species. However, mangrove ecosystems are threatened by anthropogenic activities such as the extraction of building materials, firewood, crushing plants and salt manufacturing, resulting in the disintegration of ecosystems and the loss of inhabitants. This study aimed to determine the abundance and diversity of macro-benthic invertebrates on the different parts (roots, stems and leaves) of common mangrove species of the Mbegani coast, along the Indian Ocean using a completely randomised design. Results: The sampling was done using a 1 m2 quadrat focussed on the three mangrove parts, viz. roots, stems and leaves. The results showed that the highest percentage of macro-invertebrates were recorded on Bruguera gymnorhiza (66.8%), followed by Avicennia marina (20.8%) and the least were Ceriops tagal (12.4%), such variation differed significantly between the three mangrove species across the selected plots (F(2,524) = 5.71, p = 0.035). The stems (54.4%) inhabited a large number of macro-invertebrates, followed by roots (32.8%) and the least were leaves (12.8%), which varied significantly between the three mangrove parts sampled across the selected mangrove species (F(2,524) = 7.25; p = 0.008). The majority of macro-invertebrates were planktonic feeders stuck on stems or herbivores shuttling between the roots and leaves of the plants. Macro-invertebrates recorded on Bruguiera gymnorhiza were more diverse than those found in C. tagal. The findings emphasise the importance of macro-invertebrates in the ecological balance of mangrove ecosystems. Conclusion: The study concludes that mangroves in the Mbegani ecosystem have a high potential for biodiversity and are important for the coastal community and the ecosystem of the Bagamoyo District. The results contribute to coastal resources management programmes and future surveillance activities. [ABSTRACT FROM AUTHOR]

Bakırçay is one of the important rivers of Western Anatolia, Türkiye. The objectives of this study are (a) to determine the diversity of benthic invertebrates distributed in Bakırçay, (b) to evaluate the obtained data using various biological indices, (c) to determine the interactions of species with environmental variables, and (d) to estimate the water quality level of the river using BMWP and ASPT analyses. Samplings were carried out at 15 stations between October 2017 and July 2018, seasonally. A total of 11,897 specimens belonging to 136 benthic macroinvertebrate taxa were determined. Diptera and Oligochaeta were the dominant groups with 32 (24%) and 25 taxa (18%), respectively. Station 4 has the highest species richness with 49 taxa (36%). The highest individual number (3421) was at the 14th station. Tubifex tubifex and Physella acuta have the highest dominancy (25.76%) and frequency (51.67) values, respectively. Diversity (H') values of the stations fluctuated between 1.367 (st. 13) and 3.154 (st. 12). Similarity analysis showed that the 3rd and 11th stations have the highest similarity (> 90%), while the 14th station was an outgroup and has 28% similarity ratio. BMWP and ASPT scores gave similar results, and there was no 1st class water quality in the river. On the other hand, the results of the TR-BMWP score suggested that the 1st, 4th, and 6th stations had 1st class water quality. Although some stations are classified as "good conditions," the adverse effects of pollution were mainly observed in the main channel and downstream of the river. [ABSTRACT FROM AUTHOR]

Present study was carried out during 2019 at the Vegetable Research Farm, Punjab Agricultural University, Ludhiana to generate information on diversity of invertebrates in okra. Study revealed that okra crop was harboured by 27 invertebrate species belonging to 11 orders and 26 families. Of these, maximum belonged to order Hemiptera followed by Coleoptera. Higher values of Shannon-Wiener index (1.75, 1.84) and Simpson's index (0.26, 0.17), respectively were recorded for both phytophagous arthropods and predators in untreated control plots. This is followed by neem/ other insecticides treated plots. Imidacloprid lowered the arthropod population. Occurrence of predators and phytophagous arthropods revealed a significant positive correlation with temperature (r=+0.37 to +0.99) and relative humidity (r=+0.04 to +0.80) except for few hemipterans and coleopterans. [ABSTRACT FROM AUTHOR]

Springs are perceived by human society as essential sources of drinking water, but on the other hand they represent peculiar and vulnerable ecosystems. They differ from other watercourses in the relatively high stability of their physicochemical conditions. As a result, springs represent ecosystems with an insular character, usually inhabited by specific aquatic communities.Although springs are generally considered species‐rich habitats across the world, they have been outside scientific and conservation interest in the karst mountains of the Western Carpathians. This study, therefore, examined the diversity of spring benthic macroinvertebrates and compared it with that of other watercourses of the Western Carpathian riverine landscape.The results of the study showed that, in contrast to rhithral streams, individual karst springs often had low species richness, and therefore they cannot be considered biodiversity hotspots. However, their metacommunity diversity is characterized by high taxonomic turnover, resulting in high gamma diversity. This means that the individual springs often harbour unique macroinvertebrate communities, so they are worthy of protection.However, the present level of spring habitat protection is insufficient as even springs located in protected areas are often captured as sources of drinking water and hydromorphologically or otherwise disturbed. A simple method to evaluate the spring conservation priority (CP) was developed to find a better trade‐off between their use and protection. It uses the number of Red List, endemic and crenal taxa, as well as the total species richness at each site. Based on this classification method, 16% of the springs studied reached very high CP, 39% high CP, 33% moderate CP and 12% low CP.The proposed management recommendations based on findings of conservation priority of the Western Carpathian karst springs can significantly contribute to their more effective protection and the creation of a legislative framework relating to spring habitat protection in general. [ABSTRACT FROM AUTHOR]

The Amazon rainforest has one of the greatest diversities of endemic flora and fauna compared to any other biotope on the planet. In Brazil is found most of the Amazon Forest, about 60%, and the current knowledge of this biodiversity is considered extremely heterogeneous. Thus, this research aimed to carry out a survey of the flora and fauna, specifically of invertebrates, from the Amazon in a portion of the forest in the municipality of Benevides, Pará, in order to have a better knowledge of the species belonging to that area. In aquatic environment, the collection method was through the aquatic collection net; on the ground, several methods and traps were used: entomological net, sweeping net, Malaise Trap, active search with mortar (collector flask), sweet and salty baits, pitfall and aquatic collection net. The samples obtained in the field were screened at the Biology Laboratory of the University of the State of Pará (UEPA). As a result, it was seen that, in the water, there was a predominance of the orders of Odonata (18.69%), Crustacea (14.95%), Hymenoptera and Ephemenoptera (both with 10.28%), while in the soil, in the different types of traps and collections, orders predominated: Collembola, Hymenoptera, Coleoptera, Diptera, Hemiptera and Lepidoptera. The vegetation of the forest plot in this study was mostly composed of herbs (58.75%) and trees (23.24%). At the end of the work, it was concluded that, in the research area, there is a diversity of invertebrates and quality indicators, both in the soil and in the water. Thus, it is essential to maintain the local forest, avoiding future impacts on the existing fauna and flora. [ABSTRACT FROM AUTHOR]

The Mediterranean region has a high but unevenly studied level of invertebrate diversity. Genetic-based methods, such as DNA barcoding and metabarcoding, are proposed for biodiversity assessment; however, their application is not always straightforward. The current state of data available in genetic databases limits species identification, especially in the case of certain invertebrate groups. The aim of the study was (1) to assess the diversity of seven invertebrate groups, which are potential prey for predatory arthropods, in order to facilitate the analysis of the metabarcoding of trophic interactions and, thus, expand our knowledge on biocontrol potential, and (2) to estimate the representation of local species in BOLD and NCBI GenBank databases. The DNA barcoding results consisting of sequences for 269 specimens, collected in Zadar County, within Mediterranean part of Croatia, were used for species identification and species richness assessment through the comparison of our data with the data available in BOLD and NCBI databases, and by applying species delimitation methods. Previous barcode records enabled Lepidopteran, Hemipteran, Dipteran, and Hymenopteran species identification, while Collembolan and Oligochaetes species numbers were assessed using species delimitation. Our results showed that a high number of species were unique to the study area, especially in the case of Collembolans and Oligochaetes. We confirmed that the studied area is under-researched, which was particularly evident in taxonomically demanding groups, such as Collembolans and Oligochaetes, which are rich in rare endemic species. [ABSTRACT FROM AUTHOR]

The current rate of species loss calls for immediate actions to preserve biodiversity and ecosystem functioning. Cataloguing species richness and composition, and revealing how diversity is geographically distributed are the first steps towards designing efficient conservation strategies.Here, we aim to determine diversity patterns and potential drivers of taxonomic and genetic diversity and population structure of Iberian spiders. We used a community level perspective, analysing more than 3000 DNA barcode sequences representing ~370 spider species dwelling in white‐oak forest habitats across the Spanish National Park network.By combining and comparing morphological and DNA barcode‐based species delimitation methods, we assessed their performance and identified putative factors behind cases of incongruence. Our findings uncovered potential overlooked diversity as suggested by the geographic patterns of genetic variation and put a red flag on those taxa that may be undergoing overlooked evolutionary or ecological processes.Spider functional traits associated with foraging strategy, microhabitat preference, ballooning ability and circadian activity explained the observed patterns of population structure across species but did not explain variation in genetic diversity. Overall, our study represents a major step forward in the understanding of large‐scale diversity patterns in Iberian spiders at the community level and provides relevant information to guide future conservation strategies of the so‐far largely overlooked invertebrate diversity. [ABSTRACT FROM AUTHOR]

Ecologists search for rules by which traits dictate the abundance and distribution of species. Here we search for rules that apply across three common taxa of litter invertebrates in six North American forests from Panama to Oregon. We use image analysis to quantify the abundance and body size distributions of mites, springtails, and spiders in 21 1‐m2 plots per forest. We contrast three hypotheses: two of which focus on trait–abundance relationships and a third linking abundance to species richness. Despite three orders of magnitude variation in size, the predicted negative relationship between mean body size and abundance per area occurred in only 18% of cases, never for large bodied taxa like spiders. We likewise found only 18% of tests supported our prediction that increasing litter depth allows for high abundance; two‐thirds of which occurred at a single deciduous forest in Massachusetts. In contrast, invertebrate abundance constrained species richness 76% of the time. Our results suggest that body size and habitat volume in brown food webs are rarely good predictors of variation in abundance, but that variation in diversity is generally well predicted by abundance. [ABSTRACT FROM AUTHOR]

Cultivated environments provide a habitat as well as various food resources for a large number of species of invertebrates, which can be phytophagous, predators and parasites, which act as natural enemies of agricultural pests, thus constituting means of biological control in agrosystems. An inventory of invertebrates, in particular arthropods, was made during the greenhouse tomato cultivation season of the Dawson variety in the region of Azeffoun, on the coast of Kabylia. The use of the sweep net, Barber pots and aerial or colored traps allowed us to capture 76 species divided into 46 families, belonging to 16 orders and 06 classes of invertebrates. Values of the Shannon diversity index are quite high, they vary from H'= 2.68 bits to H'= 4.84 bits. The equitability obtained for each type of trap varies from E=0.53 to E = 0.87. These values tend towards 1, which reflects a balance between the species living in the tomato crop. [ABSTRACT FROM AUTHOR]

Aim: In addition to cave size and other subterranean habitat characteristics, cave entrances are important structurers of neotropical cave communities. However, little is known about the epigean ecosystems factors that might dictate the influence of entrances and the relationship among surface and cave communities, as entrance regions are ecotonal zones between the epigean and hypogean ecosystems. We aimed to assess the influence of epigean and hypogean factors as potential drivers of invertebrate species richness in Neotropical caves as well as the influence of the regional pool of invertebrate diversity on cave invertebrate diversity. Location: Limestone caves in south‐eastern Brazil. Taxon: Invertebrates Methods: Data were collected in 48 caves within the Cerrado biome (Brazilian Savanna). The fauna sampling was performed by a direct intuitive search (DIS). Landscape characteristics and climatic parameters were accessed using geographic information systems. The characterization of the caves occurred during each sampling event. Regional diversity was based on the Taxonomic Catalog of Brazilian Fauna. To clarify the factors that significantly influence invertebrate species richness of the caves, we used generalized linear models (GLM). The relationship between regional diversity and cave diversity was evaluated based on linear models (LM). Results: Overall, 1,173 species were found, of which 72 were obligate subterranean dwellers. The cave total species richness was influenced by hypogean factors and epigean factors. The species richness of obligate cave dwellers was significantly explained only by cave size. The regional pool of invertebrate species influenced the levels of biodiversity in the studied caves. The taxa with troglobitic species tended to be more diverse in caves than expected. Main conclusions: In addition to the influences of intrinsic cave variables, we highlight the importance of epigean factors on subterranean diversity in the Neotropics. The study shows the significant influence of the regional species pool on cave faunal composition. These findings reinforce the importance of considering the surrounding areas in actions regarding cave biodiversity conservation. [ABSTRACT FROM AUTHOR]

Unlike plants and vertebrates, the ecological preferences, and potential vulnerabilities of soil invertebrates to environmental change, remain poorly understood in terrestrial ecosystems globally. We conducted a cross‐biome survey including 83 locations across six continents to advance our understanding of the ecological preferences and vulnerabilities of the diversity of dominant and functionally important soil invertebrate taxa, including nematodes, arachnids and rotifers. The diversity of invertebrates was analyzed through amplicon sequencing. Vegetation and climate drove the diversity and dominant taxa of soil invertebrates. Our results suggest that declines in forest cover and plant diversity, and reductions in plant production associated with increases in aridity, can result in reductions of the diversity of soil invertebrates in a drier and more managed world. We further developed global atlases of the diversity of these important soil invertebrates, which were cross‐validated using an independent database. Our study advances the current knowledge of the ecological preferences and vulnerabilities of the diversity and presence of functionally important soil invertebrates in soils from across the globe. This information is fundamental for improving and prioritizing conservation efforts of soil genetic resources and management policies. see also the Perspective by Phillips et al [ABSTRACT FROM AUTHOR]

The hypothesis that biotic interactions are stronger at lower relative to higher latitudes has a rich history, drawing from ecological and evolutionary theory. While this hypothesis suggests that stronger interactions at lower latitudes may contribute to the maintenance of contemporary patterns of diversity, there remain few standardized biogeographic comparisons of community effects of species interactions.Using marine seagrasses as a focal ecosystem of conservation importance and sessile marine invertebrates as model prey, we tested the hypothesis that predation is stronger at lower latitudes and can shape contemporary patterns of prey diversity. To further advance understanding beyond prior studies, we also explored mechanisms that likely underlie a change in interaction outcomes with latitude.Multiple observational and experimental approaches were employed to test for effects of predators, and the mechanisms that may underlie these effects, in seagrass ecosystems of the western Atlantic Ocean spanning 30° of latitude from the temperate zone to the tropics.In predator exclusion experiments conducted in a temperate and a tropical region, predation decreased sessile invertebrate abundance, richness and diversity on both natural and standardized artificial seagrass at tropical but not temperate sites. Further, predation reduced invertebrate richness at both local and regional scales in the tropics. Additional experiments demonstrated that predation reduced invertebrate recruitment in the tropics but not the temperate zone. Finally, direct observations of predators showed higher but variable consumption rates on invertebrates at tropical relative to temperate latitudes.Together, these results demonstrate that strong predation in the tropics can have consequential impacts on prey communities through discrete effects on early life stages as well as longer‐term cumulative effects on community structure and diversity. Our detailed experiments also provide some of the first data linking large‐scale biogeographic patterns, community‐scale interaction outcomes and direct observation of predators in the temperate zone and tropics. Therefore, our results support the hypothesis that predation is stronger in the tropics, but also elucidate some of the causes and consequences of this variation in shaping contemporary patterns of diversity. [ABSTRACT FROM AUTHOR]

In different taxonomical groups, the number of species found in urban environments tends to decline compared to adjacent nonurban environments. It is unclear whether tardigrades also conform to this pattern of diversity decline in cities. Tardigrades are microscopic invertebrates which have been understudied, despite the fact that they are cosmopolitan and found in all types of habitats. Due to their capability to withstand extreme conditions, tardigrades should be able to successfully thrive in urban environments. Here, all available information about tardigrade diversity in cities was compiled. It was quantitatively determined that tardigrade diversity declines in urban areas compared to adjacent rural areas. Geographically, closer cities are also likely to harbor a more similar set of tardigrade species. In comparison to other groups like mammals and birds, there are no tardigrade species consistently found in most studied cities. In fact, most urban tardigrades have only been found in one single city. Ultimately, the species of tardigrades found in a given city will normally depend on the set of species already living in the adjacent native environments. One question that deserves further investigation is why only a subset of such native species is able to colonize the new environmental niches available in cities. [ABSTRACT FROM AUTHOR]

Different components of biological diversity of larval Chironomidae, typically the most abundant and the most diverse of all lotic zoo-benthos, were assessed to determine their suitability in prediction of the environmental quality. Animals were collected as 73 samples at 62 riverine sites on the territory of Poland and identified morphologically. The analysis of nonlinear regression was used to compare the suitability of the seven indices of diversity. Traditional indices of taxonomic diversity (taxonomic richness, Margalef and Shannon indices) and indices of taxonomic distinctness were found to be unsuitable for this purpose because of the unimodal type of response of their values along with the gradient of the environmental quality. Contrary to them, values of two measures of phylogenetic diversity monotonically increased along with the values of environmental quality measured by official index MMI (Multimetric Macroinvertebrate Index) and were considered highly useful. The best fitted functions estimating relationships between MMI and both indices of phylogenetic diversity (total phylogenetic distance and quadratic entropy) were statistically highly significant and have high values of the fit-accuracy parameters. Original index of phylogenetic diversity ChiPDi based on total phylogenetic diversity, quadratic entropy and taxonomic richness has been presented as well as the proposal of related procedure using barcoding methods. [ABSTRACT FROM AUTHOR]

Despite over 100 years of digenean trematode parasite species descriptions, from a wide diversity of vertebrate and invertebrate host species, our ability to recognize the diversity of trematode species within a single lake remains an incredible challenge. The most challenging aspect is the identification of species from larval stages derived from intermediate hosts, due to the disjointed data of adult worm morphological descriptions, from which species are named, and links to corresponding molecular identifiers in depauperate databases. Cryptic species also play a significant role in the challenge of linking trematode larvae to adults, species identifications, and estimating diversity. Herein, we utilize a large, longitudinal dataset of snail first‐intermediate host infection data from lakes in Alberta, Canada, to infer trematode larval diversity using molecular phylogenetics and snail host associations. From our assessments, we uncover a diversity of 79 larval trematode species among just five snail host species. Only 14 species were identified to a previously described species, while the other 65 species are either cryptic or otherwise unrepresented by mitochondrial genes in GenBank. This study currently represents the largest and most diverse singular molecular survey of trematode larval fauna composed of over one thousand mitochondrial sequences. Surprisingly, rarefaction analyses indicate we have yet to capture the complete diversity of trematodes from our sampling area. [ABSTRACT FROM AUTHOR]

Cross-boundary transfers of nutrients can profoundly shape the ecology of recipient systems. The common hippopotamus, Hippopotamus amphibius, is a significant vector of such subsidies from terrestrial to river ecosystems. We compared river pools with high and low densities of H. amphibius to determine how H. amphibius subsidies shape the chemistry and ecology of aquatic communities. Our study watershed, like many in sub-Saharan Africa, has been severely impacted by anthropogenic water abstraction reducing dry-season flow to zero. We conducted observations for multiple years over wet and dry seasons to identify how hydrological variability influences the impacts of H. amphibius. During the wet season, when the river was flowing, we detected no differences in water chemistry and nutrient parameters between pools with high and low densities of H. amphibius. Likewise, the diversity and abundance of fish and aquatic insect communities were indistinguishable. During the dry season, however, highdensity H. amphibius pools differed drastically in almost all measured attributes of water chemistry and exhibited depressed fish and insect diversity and fish abundance compared with lowdensity H. amphibius pools. Scaled up to the entire watershed, we estimate that H. amphibius in this hydrologically altered watershed reduces dry-season fish abundance and indices of gamma-level diversity by 41% and 16%, respectively, but appears to promote aquatic invertebrate diversity. Widespread humandriven shifts in hydrology appear to redefine the role of H. amphibius, altering their influence on ecosystem diversity and functioning in a fashion that may be more severe than presently appreciated. [ABSTRACT FROM AUTHOR]

Wastewater treatment plants (WWTPs) have greatly improved water quality globally. However, treated effluents still contain a complex cocktail of pollutants whose environmental effects might go unnoticed, masked by additional stressors in the receiving waters or by spatiotemporal variability. We conducted a BACI (Before-After/Control-Impact) ecosystem manipulation experiment, where we diverted part of the effluent of a large tertiary WWTP into a small, unpolluted stream to assess the effects of a well-treated and highly diluted effluent on riverine diversity and food web dynamics. We sampled basal food resources, benthic invertebrates and fish to search for changes on the structure and energy transfer of the food web with the effluent. Although effluent toxicity was low, it reduced diversity, increased primary production and herbivory, and reduced energy fluxes associated to terrestrial inputs. Altogether, the effluent decreased total energy fluxes in stream food webs, showing that treated wastewater can lead to important ecosystem-level changes, affecting the structure and functioning of stream communities even at high dilution rates. The present study shows that current procedures to treat wastewater can still affect freshwater ecosystems and highlights the need for further efforts to treat polluted waters to conserve aquatic food webs. [Display omitted] • Well-treated and diluted effluent reduced invertebrate diversity. • Primary production and herbivory increased with the effluent. • Effluent toxicity was low, but it decreased total energy fluxes in stream food webs. • Even at high dilution rates, effluents can induce important ecosystem-level changes. [ABSTRACT FROM AUTHOR]

Sponges are key components of the benthic assemblages and play an important functional role in many ecosystems, especially in coral reefs. The Indonesian coral reefs, located within the so-called "coral triangle", are among the richest in the world. However, the knowledge of the diversity of sponges and several other marine taxa is far from being complete in the area. In spite of this great biodiversity, most of the information on Indonesian sponges is scattered in old and fragmented literature and comprehensive data about their diversity are still lacking. In this paper, we report the presence of 94 species recorded during different research campaigns mainly from the Marine Park of Bunaken, North Sulawesi. Six species are new for science and seven represent new records for the area. Several others are very poorly known species, sometimes recorded for the second time after their description. For most species, besides field data and detailed descriptions, pictures in vivo are included. Moreover, two new symbiotic sponge associations are described. This work aims to increase the basic knowledge of Indonesian sponge diversity as a prerequisite for monitoring and conservation of this valuable taxon. [ABSTRACT FROM AUTHOR]

Biological diversity and distribution of benthic invertebrates in the Moskva River within the frames of Moscow are studied. Totally, 72 invertebrate taxa were found including 8 invasive species with amphipod Gmelinoides fasciatus (Stebbing, 1899), an invader from the Lake Baikal. A number of observed species are characterized with high abundance and biomass while most of observed taxa are represented by a small number of individuals. The greatest species diversity was revealed for insect larvae, mainly due to Chironomidae. The main species on the investigated section of the river are various crustaceans, mainly amphipods and decapods (when present in samples) showing more than 70-90% of all biomass of zoobenthos at all stations (sites). Multivariate cluster analysis allowed concluding that bottom communities in Moskva River, the degree of their quantitative development, species richness and diversity are mainly influenced by the structure of bottom substrates rather than other factors. The most diverse benthic communities are presented on silty bottom with mixture of shells of mollusks and plant remains. The lowest diversity of benthic communities is characteristic for sites with relatively strong water and well washed sand as the main bottom substrate. Obtained data starts annual monitoring of the river at indicated stations using biological indicators, namely native amphipod Gammarus lacustris and invasive G. fasciatus. [ABSTRACT FROM AUTHOR]

Scorpions are one of the most important taxa for ecological, conservation, and biogeographic studies. Biodiversity in the pampean grassland hilly environment is relevant because of the high number of native plant and animal taxa. We studied the diversity, abundance and phenology of a scorpion community in a natural reserve from central Argentina. Samples were taken monthly using 10 pitfall traps. Five species of scorpions (269 individuals) were observed in the study site (Bothriuridae).Bothriurus prospicuuswas the most abundant species with 40.15% of the total individuals captured. The Shannon index was H´ = 0.69 and the evenness index was 0.83. Scorpion abundance was significantly different between months and was significantly correlated with monthly mean temperature. The knowledge on the scorpion fauna in “Ernesto Tornquist” Provincial Park could help in the preservation of natural grassland habitats. [ABSTRACT FROM AUTHOR]

This study describes the composition and temporal variation of the spider assemblage (Arachnida: Araneae) associated with canopies of Vochysia divergens Pohl. (Vochysiaceae) in the northern region of the Brazilian Pantanal. Three V. divergens plants were sampled in 2004, at each seasonal period of the northern Pantanal (high water, receding water, dry season and rising water), using thermonebulization of the canopies with insecticide, totaling 396 m² of sampled canopies. Analysis of abundance and richness of spider families were based on Non-Metric Multidimensional Scaling (NMDS) and Variance Analysis (ANOVA and MANOVA). A total of 7,193 spiders were collected (6,330 immatures; 88.0%; 863 adults, 12.0%) distributed in 30 families. Araneidae (1,676 individuals), Anyphaenidae (1,631 individuals), Salticidae (1,542 individuals) and Pisauridae (906 individuals), were predominant, representing 80.0% of the sample. Ten different guilds were registered: aerial hunters, orb-weavers, nocturnal aerial runners and diurnal space web weavers dominated, sharing most ecological niches. The spider assemblage is affected by changes in the habitat structure, especially by the seasonal hydrological regime and variations in the phenology of V. divergens. The assemblage is composed of different groups of spiders. The dominant taxa and behavioral guilds differ in the different seasonal periods. Spiders were more abundant during the dry and rising water seasons, most likely reflecting a greater supply of potential prey, associated with new foliage and flowering at the canopy. The displacement of soil dwelling spiders to the trunks and canopies before and during the seasonal floods can change the structure and composition of the canopy assemblages. Oonopidae, Gnaphosidae and Caponiidae, were more frequent during the rising and high water seasons, which indicates that these taxa use the canopies of V. divergens as a refuge during the seasonal flooding in the Pantanal. [ABSTRACT FROM AUTHOR]

Despite the large number of river restoration projects carried out worldwide, evidence for strong and long-term positive ecological effects of hydromorphological restoration on macroinvertebrates is scarce. To improve the understanding of the success and failure of restoration measures, a standardized field study was carried out in nineteen paired restored and degraded river sections in mid-sized lowland and mountain rivers throughout Europe. We investigated if there were effects of restoration on macroinvertebrate biodiversity, and if these effects could be related to changes in microhabitat composition, diversity and patchiness. Effects were quantified for all taxa combined, as well as Ephemeroptera, Plecoptera and Trichoptera separately. Additionally, species trait classifications of microhabitat preference types were used as a functional indicator. Restoration had no overall positive effects on the selected macroinvertebrate metrics. Rather, we did find positive relationships between the macroinvertebrate responses and the effect of restoration on the diversity and patchiness of microhabitats. Furthermore, the effects on macroinvertebrates could be related to changes in the cover of specific substrate types in the restored sections. We conclude that the limited effect of restoration on macroinvertebrate diversity overall reflected, at least in part, the limited effect of most restoration measures on microhabitat composition and diversity. [ABSTRACT FROM AUTHOR]

During the present study we examined the monthly dynamics of the macrozoobenthic invertebrate communities from Valea Roşia River, for three months (July September) 2013. The sampling sites were chosen both in the spring area and along the river course in different point allowing us to investigate a great number of habitats. We followed the modifications of the macrozoobenthic invertebrate communities due to the hydrological characteristics of the river sectors, the monthly dynamics and those produced by the human impact. We calculated Shannon Wienner diversity index and Hilsenhoff index to determine the pollution level in the analysed sectors. [ABSTRACT FROM AUTHOR]

1. Temporary streams comprise a large proportion of the total length of most stream networks, and the great majority of arid-land stream networks, so it is important to understand their contribution to biotic diversity at both local and landscape scales. 2. In late winter 2010, we sampled invertebrate assemblages in 12 reaches of a large arid-land stream network (including perennial and intermittent headwaters, intermittent middle reaches and perennial rivers) in south-east Arizona, U.S.A. Intermittent reaches had then been flowing for c. 60 days, following a dry period of more than 450 days. We sampled a subset of the perennial study reaches three more times between 2009 and 2011. Since intermittent reaches were dry during these additional sampling periods, we used assemblage data from two other intermittent streams in the study network (sampled in 2004-05 and 2010) to explore interannual variability in intermittent stream assemblage composition. 3. Invertebrate richness was lowest in intermittent reaches, despite their often being connected to species-rich perennial reaches. The assemblages of these intermittent reaches were not simply a subset of the species in perennial streams, but rather were dominated by a suite of stoneflies, blackflies and midges with adaptations to intermittency (e.g. egg and/or larval diapause). On average, 86% of individuals in these samples were specialists or exclusive to intermittent streams. Predators were 7-14 times more abundant in perennial than in intermittent reaches. 4. Despite being separated by long distances (12-25 km) and having very different physical characteristics, the assemblages of perennial headwaters and rivers were more similar to one another than to intervening intermittent reaches, emphasising the prime importance of local hydrology in this system. 5. The duration and recurrence intervals of dry periods, and the relative importance of dispersal from perennial refuges, probably influence the magnitude of biological differences between neighbouring perennial and temporary streams. Although perennial headwaters supported the highest diversity of invertebrates, intermittent reaches supported a number of unique or locally rare species and as such contribute to regional species diversity and should be included in conservation planning. [ABSTRACT FROM AUTHOR]