Peak Abundance Research Articles

Evaluation of The Diversity of Durum Wheat Coleoptera (Triticum Durum Desf.) in the Region of Sigus Oum El Bouaghi (Eastern Algeria)

The Oum El Bouaghi region in Eastern Algeria, long considered as a cereal-growing area is nowadays a durum wheat production region par excellence. Although the damage caused by Coleoptera is very significant, studies on the knowledge of their diversity are few and remain limited for some entomological groups. Our work is the first step to evaluate the diversity of Coleoptera and the long-term impact of taking biological management measures against harmful fauna in favour of more environment friendly agriculture. To assess the beetle community, different sampling methods were combined (Barber trap, coloured traps, mowing net and sight hunting). Evaluation of the results of a single campaign showed that Coleoptera infested with durum wheat vary in abundance and diversity. We identified more than 100 species of Coleoptera belonging to 22 different families for a total number of 5698 individuals belonging mainly to the Carabidae, Curculionidae, Chrysomelidae, Scarabidae and Staphylinidae families. Although the majority of Coleoptera collected are pests of durum wheat crops (47.57%) the case of Tropinota hirta, Notaris sp or Oulema melanopus in particular, there was an interesting presence of predators (28.15%) the case of Carabidae or Staphylinidae in particular even with low relative abundance. The temporal evolution of the Coleoptera showed that the species diversity indicated a peak of abundance at the full tillering stage following an accentuated vegetative development of the host plant, and the presence of weeds. The data collected in this way constitute a basis for a preliminary knowledge of the durum wheat Coleoptera and can thus be used to design pest control strategies.

Abundance of montane salamanders over an elevational gradient.

Climate change is expected to systematically alter the distribution and population dynamics of species around the world. The effects are expected to be particularly strong at high latitudes and elevations, and for ectothermic species with small ranges and limited movement potential, such as salamanders in the southern Appalachian Mountains. In this study, we sought to establish baseline abundance estimates for plethodontid salamanders (family: Plethodontidae) over an elevational gradient in Great Smoky Mountains National Park. In addition to generating these baseline data for multiple species, we describe methods for surveying salamanders that allow for meaningful comparisons over time by separating observation and ecological processes generating the data. We found that Plethodon jordani had a mid‐elevation peak (1,500 m) in abundance and Desmognathus wrighti increased in abundance with elevation up to the highest areas of the park (2025 m), whereas Eurycea wilderae increased in abundance up to 1,600 m and then plateaued with increasing uncertainty. Litter depth, herbaceous ground cover, and proximity to stream were also important predictors of abundance (dependent upon species), whereas daily temperature, precipitation, ground cover, and humidity influenced detection rates. Our data provide some of the first minimally biased information for future studies to assess changes in the abundance and distribution of salamanders in this region. Understanding abundance patterns along with detailed baseline distributions will be critical for comparisons with future surveys to understand the population and community‐level effects of climate change on montane salamanders.

Occurrence and severity of mite Polyphagotarsonemus latus (Tarsonemidae) on chili plants: Analysis of pest‐weather and host plant characteristics

AbstractThe abundance, infestation, and severity of the mite Polyphagotarsonemus latus were studied on the chili (Capsicum frutescens L., Solanaceae) varieties BARI Morich 1, BARI Morich 2, BARI Morich 3, BINA Morich 1, and Bogura Morich from November 2017 to June 2018. The abundance of mites was found from 05 February to 28 May, and the peak abundance on the chili varieties occurred on 09 April. Mite population showed the highest and the lowest occurrences on BINA Morich 1 and BARI Morich 2, respectively. The abundance of P. latus on the chili varieties showed significant positive correlation with temperature, and the relationship with relative humidity and rainfall was negative. Mite population was negatively correlated with leaf trichomes of all the chili varieties, and depicted significant negative correlation with the leaf area of BARI Morich 1, BARI Morich 3 and BINA Morich 1. The number of flower of the chili varieties BARI Morich 3 and BINA Morich 1, and number of fruit of the varieties BARI Morich 1, BARI Morich 3, BINA Morich 1 and Bogura Morich showed significant negative correlation with mite population. The chili varieties demonstrated significant differences within their leaf curl indices (LCI), and infestation levels of flower and fruit. The BARI Morich 2 revealed the lowest level of mite infestation on flowers and fruits. The varieties BARI Morich 1, BARI Morich 2, and Bogura Morich contained <50% LCI, which were categorized as moderately resistant, and the rest varieties were categorized as susceptible due to >50% LCI.

FEATURES OF THE SEASONAL DYNAMICS OF PHYTOPLANKTON AT THE LEFT BANK OF THE VOLGA REACH OF KUIBYSHEV RESERVOIR (REPUBLIC OF TATARSTAN, RF)

Biocenosis of shallow waters of lowland reservoirs lives in various habitat regimes and are characterized by a special structural and functional organization. To fully elucidate these features, it is necessary to research several hydrologically different areas simultaneously. This study was conducted to evaluate the effect of seasonal dynamics on the phytoplankton community of the Volga reach of the Kuibyshev reservoir near the left bank. During the observation period, 112 taxa were found in the phytoplankton of the studied site. The greatest number of taxa were identified from the groups of diatoms (44%) and green (28%) algae. Some other less diverse groups are blue-green (16%), Chrysophyta (6%), cryptophyta and dinophyta (3%), etc. Cosmopolitan and planktonic species of algae prevail in terms of environmentally-geographical characteristics. Concerning halobility, most species are indifferent, and in terms of pH, the most common are the indifferent alkaliphile + alkalibiontic algae. The total abundance and biomass of planktonic algae range 8.49-1661.09 mln.cl./l and 10.28 -114.11 mg/l respectively. Some important dominant species are blue-green algae Microcystis aeruginosa f. flos-aquae, Aphanizomenon flos-aquae, Anabaena flos-aquae, Anabaena scheremetievi, Aulacoseira italica, Navicula sp., Carteria globosa, Chlamydomonas sp., Pandorina morum, Scenedesmus guadricauda. Seasonal dynamics of phytoplankton have two peaks of abundance and biomass which are at the end of the first decade of July and in the second decade of August. Both maxima are due to the massive development of blue-green algae, which causes water to “bloom”. The phytoplankton of the investigated section of the Kuibyshev reservoir is dominated by β-mesosaprobic organisms.

Design and development of a compact thermal ionization mass spectrometer for isotope ratio measurement of uranium.

A new compact thermal ionization (TI) mass spectrometer, for the isotope ratio analysis of the elements relevant to nuclear applications, has been designed and developed. The new development offers superior performance in terms of sensitivity, precision and a compact footprint in comparison with the conventional one. The main feature of the TI mass spectrometer is the magnetic sector analyser with a sector radius of 20 cm (instead of 30/27 cm in conventional/commercial geometry). An apparent reduction in dispersion has been adequately compensated by employing variable dispersion zoom optics (VDZO). The theoretical calculations were validated by computer simulations using SIMION 7.0, leading to the finalization of the mechanical design. Experimental evaluation was carried out using standard TI mass spectrometric methodology to determine the parameters, namely peak flatness, mass range, sensitivity, abundance sensitivity, resolution and precision. The multi-collector resolution was 496, and the maximum mass was m/z 382. The sensitivity for uranium was found to be better than 1 ion for 500 atoms, and an abundance sensitivity of 50 ppm at m/z 237 was obtained. The peak flatness for the uranium peak was 3200 ppm of mass. The precision for the isotopic ratio 235 U/238 U was found to be 0.05% for the U200 standard. A new compact TI mass spectrometer with a 20 cm sector radius has been designed and developed. The advantage of larger dispersion produced by the VDZO (developed in-house) was exploited when deciding the 20 cm sector radius. The comparison study with the conventional TI mass spectrometer shows an enhanced (1.5×) sensitivity and an improved precision (0.05%) for the 235 U/238 U ratio of U200.

Summarizing abundance changes in waterbirds: some problems and a possible solution

After conducting replicated counts of migratory waterbirds at a given wetland, some authors choose to compute the mean abundance throughout the study period, whereas others report the peak value or the cumulative total. Here, we use fictitious and real examples to illustrate how some of these procedures can lead to distorted conclusions. For species with skewed abundance distributions, the mean does not summarize the central tendency in the data, and the median should be used; however, for many migratory waterbirds, median abundances at a given site can be null. Also, the probability of double-counting the same individuals increases when replicated surveys cover a long time. Moreover, since the cumulative abundance of a species/assemblage increases with the number of surveys, misleading results can be obtained if researchers apply different sampling efforts. Finally, the ranking and selection of wetlands for waterbird conservation can be misguided if cumulative totals are compared against standard criteria (i.e., Ramsar sites, IBAs). To avoid the above mentioned problems, we propose to use the maximum, peak abundance of a given waterbird species during the course of the study, or the sum of maxima, peak values across all the species in the same waterbird assemblage.

High proliferation of Pseudo-nitzschia cf. arenysensis in the Adriatic Sea: ecological and morphological characterisation

The aim of the present study isto characterise the diatom Pseudo-nitzschia community during a bloom period together with environmental conditions. High proliferation of Pseudo-nitzschia spp. was observed in September 2017 at the shellfish breeding area in the Krka River estuary (Central eastern Adriatic Sea). The peak of abundance (1.8 x 106 cells L-1) was recorded at 7 m depth, and the increased abundance persisted for four weeks.Morphological analyses of field samples based on scanning electron microscopy (SEM) revealed that Pseudo-nitzschia cf. arenysensis was prevailing (94%) in the Pseudo-nitzschia assemblage. Several strains were successfully isolated from net samples in order to better define morphological features and phylogenetic characterisation. The isolated Pseudo-nitzschia strains corresponded morphologically to the P. cf. arenysensis from the field samples, based on our SEM observations. Phylogenetic analysis demonstrated that the Croatian strains grouped with P. arenysensis using the ITS and LSU rDNA sequences. Spearman rank correlation showed that salinity was an important environmental factor affecting the vertical distribution of Pseudo-nitzschia spp. in this highly variable area. Availability of increased concentration of orthophosphates and ammonium and low Si: TIN ratio may have promoted the bloom of P. cf. arenysensis in the estuary.

Estado de las poblaciones del Rayador (Rynchops niger) en Chile

Black skimmers (Rynchops niger) visit the coast of Chile during the Southern summer, being observed in flocks of different sizes, mainly in coastal wetlands. Through the joint use of a database of citizen science observations together with our long-term monitoring, we estimate that the population size for the species in Chile reaches 10,227 individuals. Three sites congregate more than 50% of the population, these sites are the estuaries of Mataquito and Itata river, and Tubul. The analysis of the relative abundance throughout the year for four geographic macrozones would reflect the movement of the species on the coasts of Chile. The Northern zone shows an abundance peak in November with the arrival of individuals, yet its return strategy keeps not being so clear. The Central-North and Central zones of the country show two peaks in the arrival and departure of individuals, suggesting a rather transit use. The existence of a single peak in February, in addition to the highest concentrations of individuals, would indicate that the Central-Southern and Southern areas of the country would potentially be the destination for a large part of the population of black skimmers. The radiotelemetry monitoring of individuals allowed the detection of movement of individuals between a network of coastal wetlands. These displacements would occur frequently throughout the season and both north and southbound. This study provides relevant information for the status of the species in Chile, a country that is habitat for a potentially significant proportion of the cinerascens subspecies during the non-breeding period.

In situ observations show vertical community structure of pelagic fauna in the eastern tropical North Atlantic off Cape Verde

Distribution patterns of fragile gelatinous fauna in the open ocean remain scarcely documented. Using epi-and mesopelagic video transects in the eastern tropical North Atlantic, which features a mild but intensifying midwater oxygen minimum zone (OMZ), we established one of the first regional observations of diversity and abundance of large gelatinous zooplankton. We quantified the day and night vertical distribution of 46 taxa in relation to environmental conditions. While distribution may be driven by multiple factors, abundance peaks of individual taxa were observed in the OMZ core, both above and below the OMZ, only above, or only below the OMZ whereas some taxa did not have an obvious distribution pattern. In the eastern eropical North Atlantic, OMZ expansion in the course of global climate change may detrimentally impact taxa that avoid low oxygen concentrations (Beroe, doliolids), but favour taxa that occur in the OMZ (Lilyopsis, phaeodarians, Cydippida, Colobonema, Haliscera conica and Halitrephes) as their habitat volume might increase. While future efforts need to focus on physiology and taxonomy of pelagic fauna in the study region, our study presents biodiversity and distribution data for the regional epi- and mesopelagic zones of Cape Verde providing a regional baseline to monitor how climate change may impact the largest habitat on the planet, the deep pelagic realm.

Fixed-Charge Generation Derivatization for the Analysis of Carbonyl Compounds by Electrospray Ionization Mass Spectrometry

The fixed-charge generation derivatization approach based on a reaction with ω-N,N-dimethylaminoalkylamines followed by quaternization with alkyl halides was applied to the analysis of aliphatic aldehydes and ketones, as well as ketosteroids by electrospray ionization (ESI) mass spectrometry. Both stages of reaction proceed quantitatively, and the registered ESI mass spectra of the products contain abundant peaks of the corresponding ammonium cations. In most cases, the dissociation of the last named compounds under collision activation results only in the loss of the terminal trialkylamino group as a neutral species. Such predictable fragmentation can be used for developing of highly sensitive methods of analysis based on selected reaction monitoring.

PSIX-16 Investigating the development of the fecal microbiome in growing diary calves

Abstract Development of the gut microbiome in young animals is critical for maximizing productivity in adults through beneficial functional contributions of symbiotic microbial communities to the health and nutrition of their host. To gain further insight into this process, development of the fecal microbiome in 12 dairy calves was investigated. Fecal bacterial composition was determined at four time points (weeks 0, 4, 8 and 12) using the 16S rRNA gene through PCR-amplification of the V1-V3 regions from fecal microbial genomic DNA, followed by Illumina MiSeq 2X300 sequencing. A comparative analysis of the most highly represented Operational Taxonomic Units (OTU) using the non-parametric Kruskal-Wallis sum-rank test and Wilcoxon pairwise test identified both known and uncharacterized fecal bacterial species whose abundance fluctuated during development of the calves. Four highly represented OTUs were found to have a peak of abundance at week 0, which was followed by significantly lower abundance at later time points (P < 0.05). Notably, OTU JA_ 89-27339, peaked at week 0 (39.3% ± 3.6%), then declined at later time points with respective means of 2.3%, 0.1% and 0.05%. Seven other OTUs were found to peak at an intermediate time point (P < 0.05), including OTU JA_46-21334 which was found in highest abundance at week 4 (4.5% ± 1.2%) compared to means with a range of 0.001% to 0.01% for the other time points. In contrast, another set of well represented OTUs were found to increase in abundance with time, which included OTU JA_84-17601 whose abundance was highest at week 12 (1.4% ± 0.3%) (P < 0.05). These results are indicative of microbial succession in the gastrointestinal tract of dairy calves and highlight candidate bacterial species whose function could be manipulated towards improving the health and productivity of growing dairy calves.

Population Abundance of the Serpentine Leaf Miner Liriomyza trifolii (Burgess) (Diptera: Agromyzidae) on Four Winter Host Plants

Background: The American serpentine leafminer, L. trifolii (Burgess), is one of the most problematic insect pest species attacking large number of vegetable crops, weeds and, ornamentals.
 Objectives: The purpose of this study is to investigate population abundance and host plant preference of L. trifolii on four winter host plants under Libyan conditions.
 Methods: Four winter host plants were studied [broad bean (Veciafaba), pea (Pisum sativum), fenugreek (trigonella finum gradum) and snow thistle (Sonchus oleraceus)]. The experimental field was about 1600m2 which divided to 12 equal plots (4 plots for each plant). Hundred leaflets infested with L. trifolii were taken from each host plant. Samples were kept in plastic bags and transferred to be examined in the laboratory. Number of living L. trifolii larvae were counted and recorded.
 Results: Four winter host plants were targeted for this study [broad bean (Veciafaba), pea (Pisum sativum), fenugreek (Trigonella foenum graecum) and snow thistle (Sonchus oleraceus)] during the growing season 2018/2019 in Alejelat region. L trifolii showed low populations in December on all studied host plants. then, developed high populations in February and March then the population decreased till the end of the growing season. L trifolii recorded four peaks of abundance on all host plants, except snow thistle (3 peaks) the highest peak recorded 488, 322, 152 and 187 individuals/ 100 infested leaflets on broad bean, pea, fenugreek and snow thistle respectively. L. trifolii showed its highest monthly average numbers in February on Broad bean, Pea and, Fenugreek recording (383.25 ± 81.05, 256.75 ± 55.18 and, 101.5 ± 37.36 individuals / 100 infested leaflets) respectively and, (153.27 ± 27.10 individuals / 100 infested leaflets) for Snow thistle in April. On the other hand, the lowest monthly average numbers occurred in April on the four studied host plants recording (240.71 ± 113.11, 176.48 ± 59.22, 71.28 ± 24.05 and, 106.28 ± 47.73 individuals / 100 infested leaflets).

Analysis of Isotopic Abundance Ratio of Consciousness Energy Healing Treated Metronidazole Using LC-MS and GC-MS Spectrometry

Metronidazole is an antibiotic and useful for the antibacterial and antiprotozoal medication. This study was performed to investigate the impact of the Trivedi Effect®-Biofield Energy Healing Treatment on the structural properties and the isotopic abundance ratio of metronidazole using LC-MS and GC-MS spectroscopy. Metronidazole sample was divided into two parts, one part of metronidazole was considered as control (no Biofield Energy Treatment was provided), while the second part was treated with the Trivedi Effect®-Consciousness Energy Healing Treatment remotely by a renowned Biofield Energy Healer, Alice Branton and termed as a treated sample. The LC-MS spectra of both the samples of metronidazole at the retention time (Rt) 2.61 minutes exhibited the mass of the protonated molecular ion peak at m/z 172 M+H+ (calculated for C6H10N3O3+, 172.07). The LC-MS based isotopic abundance ratio of PM+1/PM (2H/1H or 13C/12C or 15N/214N or 17O/16O) in the treated metronidazole was significantly increased by 8.24% compared with the control sample. Thus,13C, 2H, 15N,and17O contributions from (C6H10N3O3)+ to m/z 173 in the treated sample were significantly increased compared with the control sample. The GC-MS based isotopic abundance ratio of PM+1/PM in the treated metronidazole was significantly increased by 5.92% compared with the control sample. Hence,13C, 2H, 15N, and217O contributions from (C6H9N3O3)+ to m/z 172 in the Biofield Energy Treated sample were significantly increased compared with the control sample. However, the isotopic abundance ratio of PM+2/PM in the treated metronidazole was significantly decreased by 18.2% compared with the control sample. Hence,18O contributions from (C6H9N3O3)+ to m/z 173 in the treated sample were significantly decreased compared with the control sample. The isotopic abundance ratio of PM+1/PM (2H/1H or 13C/12C or 15N/14N or 17O/16O) and PM+2/PM (18O/16O) in the treated metronidazole was significantly altered compared to the control sample. From the results, it can be hypothesized that the changes in isotopic abundance and mass peak intensities could be due to changes in nuclei possibly through the interference of neutrino particles via the Trivedi Effect® - Consciousness Energy Healing Treatment. The new form of treated metronidazole would be better designing novel pharmaceutical formulations that might offer better therapeutic response against bacterial and protozoal infection in the vagina (bacterial vaginosis), stomach (giardiasis, trichomoniasis, pseudomembranous colitis), joints (pelvic inflammatory disease), liver, skin, brain, and respiratory tract, aspiration pneumonia, rosacea, intra-abdominal infections, lung abscess, fungating wounds, periodontitis, amoebiasis, oral infections, etc.

The lunar compass of European glass eels (Anguilla anguilla) increases the probability that they recruit to North Sea coasts

AbstractThe European eel hatches in the Sargasso Sea and migrates across the Atlantic Ocean toward Europe. At the continental shelf, larvae metamorphose into glass eels and then recruit to coastal habitats and estuaries. Among other cues, glass eels orient in situ using lunar cues, but what role this lunar compass plays in their recruitment to the coast is unknown. To assess this, we incorporated empirical in situ observations of glass eel swimming and lunar‐driven orientation into a biophysical advection model. We simulated dispersal of glass eels drifting with the North Atlantic Current to test the hypothesis that lunar‐driven swimming and orientation behavior affects recruitment to North Sea coasts. Particles were released from the continental slope north of Scotland, an obligate passage for migrating eel larvae. Four numerical experiments were conducted: one with passive drift and three including glass eel swimming speeds (ranging from 3 to 12 cm/s) and lunar‐driven orientation. With a speed of 3 cm/s, the lunar compass increased recruitment to the North Sea coasts of Southwestern Norway and Scotland by 34%–40%. Conversely, orientation behavior decreased recruitment to northern areas like Iceland (−46%), the Faroe Islands (−39%) and Northern Norway (−49%). Behavior affected the timing of recruitment to Southwestern Norway, causing peaks of abundance in May–June, but not to other regions. These results show that lunar‐driven orientation and swimming behavior observed in glass eels substantially increases their recruitment to North Sea coasts. Results agree with the distribution of eel in northern Europe, which decreases in abundance with increasing latitude.

Carabus Population Response to Drought in Lowland Oak Hornbeam Forest

Forest management practices and droughts affect the assemblages of carabid species, and these are the most important factors in terms of influencing short- and long-term population changes. During 2017 and 2018, the occurrences and seasonal dynamics of five carabid species (Carabus coriaceus, C. ulrichii, C. violaceus, C. nemoralis and C. scheidleri) in four oak hornbeam forest stands were evaluated using the method of pitfall trapping. The climate water balance values were cumulatively calculated here as cumulative water balance in monthly steps. The cumulative water balance was used to identify the onset and duration of drought. The number of Carabus species individuals was more than three times higher in 2018 than in 2017. Spring activity was influenced by temperature. The extremely warm April in 2018 accelerated spring population dynamics; however, low night temperatures in April in 2017 slowed the spring activity of nocturnal species. Drought negatively influenced population abundance, and the effect of a drought is likely to be expressed with a two-year delay. In our investigation, a drought in 2015 started in May and lasted eight months; however, the drought was not recorded in 2016, and 2016 was evaluated as a humid year. The meteorological conditions in the year influenced seasonal activity patterns and the timings of peaks of abundance for both spring breeding and autumn breeding Carabus species.

Elucidation of Gut Microbiota-Associated Lipids Using LC-MS/MS and 16S rRNA Sequence Analyses.

SummaryHost-microbiota interactions create a unique metabolic milieu that modulates intestinal environments. Integration of 16S ribosomal RNA (rRNA) sequences and mass spectrometry (MS)-based lipidomics has a great potential to reveal the relationship between bacterial composition and the complex metabolic network in the gut. In this study, we conducted untargeted lipidomics followed by a feature-based molecular MS/MS spectral networking to characterize gut bacteria-dependent lipid subclasses in mice. An estimated 24.8% of lipid molecules in feces were microbiota-dependent, as judged by > 10-fold decrease in antibiotic-treated mice. Among these, there was a series of unique and microbiota-related lipid structures, including acyl alpha-hydroxyl fatty acid (AAHFA) that was newly identified in this study. Based on the integrated analysis of 985 lipid profiles and 16S rRNA sequence data providing 2,494 operational taxonomic units, we could successfully predict the bacterial species responsible for the biosynthesis of these unique lipids, including AAHFA.

Meroplankton seasonal dynamics in the high Arctic fjord: Comparison of different sampling methods

Meroplankton comprise mainly of pelagic larvae of benthic invertebrates and play an important role as consumers and prey in coastal ecosystems. During a year-round study in Isfjorden (Svalbard Archipelago; >78°N), two locations (stations North and South) were sampled every third month to capture seasonal dynamics of meroplankton at high-latitudes, using different sampling methods (vertically hauled WP2 plankton net, and SCUBA diver-operated: horizontal towed net and underwater suction pump). Independent of sampling methods, seasonality was the factor that explained the largest part of variation in meroplankton composition (31.8%, PERMANOVA). Distinct seasonal abundance peaks were found of the following taxa: Polychaeta larvae and Cirripedia nauplii in spring; Bivalvia veligers, Echinodermata ophioplutei, and Cirripedia cypris during summer; while Bryozoa cyphonautes in autumn. These changes were driven mainly by water temperature, chlorophyll a concentration, and photoperiod, which according to DistLM routine, jointly explained 36.7% of meroplankton variability. Our results support the theory that planktotrophy is an important larval development strategy in some high Arctic taxa, e.g. Bivalvia and Cirripedia. We also observed that the southern part of Isfjorden was more productive and affected by the advection of Atlantic waters; while the northern location was influenced by the sea ice drift, coming from the north-eastern part of the Isfjord system in winter and spring, and was characterised by higher meroplankton abundances. The comparison of the number of taxa collected by each method and multivariate dispersion index between the standard WP2 plankton net and the remaining devices, operated by SCUBA divers, proved that WP2 is the most optimal method to collect meroplankton, especially from deeper waters. However, an underwater, manually operated suction pump would be a good choice in shallow coastal areas, especially with a dense kelp forest, where using a WP2 net is impossible. The joint use of the WP2 net and suction pump gives the highest value of multivariate dispersion index for the total community, as it additionally allows for the collection of demersal and epibenthic animals which are often omitted by standard net sampling methods, so this combination is worth recommending in studying shallow coastal ecosystems.

The analysis of planktonic algae structure in the Volga and Kama rivers (Republic of Tatarstan)

The paper presents the results of a comparative analysis of planktonic algae structure in the Volga and Kama rivers at the confluence of the Kuibyshev reservoir. The author has also assessed the trophic state of the studied river sections in 2012. The hydrochemical regime of the Kuibyshev reservoir is heterogeneous and is determined by the chemical composition of the Volga and Kama waters, which differ in the ratio of ions and mineralization. The ionic composition of the Kama waters is often dominated by sulfates. The salinity depending on the season and water content of the year ranges from 168 to 674 mg/l. The Volga waters contain calcium bicarbonate and have a lower mineralization (120130 mg/l). The variability of the incoming water, the amount of runoff, the degree of volume drawdown within water bodies and groundwater inflows primarily affect the conditions for planktonic algae existence. In the phytoplankton of the Volga and Kama rivers (areas before their confluence in the Kuibyshev Reservoir), 123 taxa of algae were identified during the 2012 growing season. The waters of the Volga River have a higher species diversity (107 species). The phytoplankton of the Kama River is less diverse (76 species). In the seasonal dynamics of phytoplankton in the studied river sections, two peaks of abundance and biomass are observed by the middle of summer and at the end of it, when the maximum values of abundance and biomass are reached. The waters of the investigated sections of the Volga River is characterized by a complex of phytoplankton of blue-green, diatoms and green algae, while the Kama River is dominated by diatom phytoplankton. In summer and autumn the blooming of water in both rivers is due to the massive development of blue-green algae of the genera Microcystis, Aphanizomenon, Anabaena, Oscillatoria. The waters of the Volga and Kama rivers in 2012 during the study period corresponded to the mesasaprobic type and moderately polluted zone; the waters of the Kama River had higher saprobity indices. The trophic status of the rivers under consideration in the study area was mostly related to the eutrophic type; during the periods of maximum reproduction of blue-green algae to the hypereutrophic type.

Wing size and parity as markers of cohort demography for potential Anopheles (Culicidae: Diptera) malaria vectors in the Republic of Korea.

Wing lengths of parous (P) and nulliparous (NP) PCR-identified female Anopheles belenrae, An. kleini, An. pullus, and An. sinensis were determined from weekly trap collections at Camp Humphreys (CH), Ganghwa Island (GH), and Warrior Base (WB), Republic of Korea (ROK) during Jun-Oct, 2009. Wing length was greatest at the beginning and end of the study period. Wing length of NPs tended to be less than that of Ps before the period of maximum greening (Jul-Aug) but greater thereafter. Larger specimens tended to be Ps, and weekly wing length of Ps appeared less variable than NPs, possibly due to selection. A bimodal wing length frequency distribution of An. sinensis suggested two forms comprising small- (≤4.5 mm, SW) and large-winged females (>4.5 mm, LW). LW comprised the majority of peaks in abundance, however %SW, while still a minority, often increased during these times suggesting a density-dependent effect. At WB and GH, a two to three-week periodicity in %SW was obvious for An. sinensis and An. kleini. Analyses of weather station and satellite data showed that smaller-winged An. sinensis were associated with warmer, more humid, and greener times of the year. SW and LW specimens possibly result from agricultural practices that are common across large areas; regular synchronous peaks of SW and LW were observed from different sites. Peaks in SW Ps followed peaks in NPs in a 'ripple effect' one to two weeks apart, suggesting that wing length combined with parity could be used to follow the emergence and survival of mosquito cohorts.

Effect of Salinity on the Zooplankton Community in the Pearl River Estuary

Understanding the relationship between the zooplankton distribution and salinity may provide key information to understand ecosystem function under the condition of a global mean sea level rise caused by global climate change. However, little is known about how increasing salinity level will affect the entire zooplankton community on a large scale. Here we completed 1 year of field investigations on the Pearl River Estuary and analyzed the distribution and structure of the zooplankton community. A total of 68 zooplankton species were identified during the survey. The number and diversity (richness, evenness, Shannon index, and Simpson’s index) of the zooplankton species decreased as salinity increased from 0.10 to 21.26. Salinity negatively affected the abundances of rotifers, cladocerans, and total zooplankton, while it had little effect on copepod abundance. Some salt-tolerant species, such as Keratella tropica, Polyarthra vulgaris, and Paracalanus crassirostris, survived at high-salinity sites. A pattern was observed at all sites: the peak in copepod abundance always occurred when rotifers were abundant (sites S1 and S2) or after rotifer abundance reached a maximum level (sites S3, S4, and S5). In general, salinity was the most important environmental factor shaping zooplankton biodiversity and abundance. This study provides insight into potential biodiversity and structure of the zooplankton community in response to salinity change.