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1.
The effects of land use on black fly assemblages were investigated in submontane rivers (the Ľubochnianka River, the Revúca
River, upper Váh River catchment) in the Carpathians. We recorded 11 black fly species in the Ľubochnianka River and 10 species
in the Revúca River. Land use differs between the catchments; the Ľubochnianka is a primarily forested catchment, and the
Revúca is markedly deforested catchment. Fifteen environmental variables were analysed. Based on the results provided by CANOCO,
phosphorus level and stream slope are the most important variables and have significant influences on the variability of black
fly assemblages. In spring, Prosimulium rufipes occurred along the entire lengths of the streams. The black fly assemblage of the Revúca River differs from the assemblage
of the Ľubochnianka River mainly by its higher abundances of Simulium variegatum and Simulium ornatum, by the presence of Simulium carthusiense, and by the absence of Prosimulium hirtipes. 相似文献
2.
Emergence patterns of blackflies (Diptera: Simuliidae) were investigated for 2 years at nine sites in the Plitvice Lakes area of Croatia, using pyramid‐type traps. A total of 38 012 specimens representing 10 haematophagous species were collected. The dominant species was Simulium angustipes Edwards, 1915, a vector transmitting avian trypanosomes. Water temperature, alkalinity, conductivity and habitat type represented the factors with the greatest degree of influence on blackfly species composition, structure and distribution along a longitudinal gradient of this oligotrophic karstic hydrosystem. Simulium angustipes was highly associated with lake outlets. The blackfly communities at all sites were dominated by species typical of the rhithral zone, but there was a shift in species composition along a longitudinal gradient from the hypocrenal–epirhithral to the epirhithral–metarhithral zone. Multiple generations per year were detected in S. angustipes, whereas in Simulium costatum Friederichs, 1920, the number of generations differed between sites with constant and those with variable water temperature. 相似文献
3.
Árni Einarsson Arnthor Gardarsson Gísli Már Gíslason Gudni Gudbergsson 《Hydrobiologia》2006,567(1):183-194
We examined annual variation in production, recruitment and density of the three most abundant vertebrate species of the River
Laxá at Lake Myvatn, Iceland: Barrow’s goldeneye, Bucephala islandica, harlequin duck, Histrionicus histrionicus, and brown trout, Salmo trutta, in relation to food resources and other environmental variables. The study is largely based on correlations from long-term
monitoring series in the period 1975–2002. Production of young in the harlequin duck was significantly correlated with food
resources (the blackfly, Simulium vittatum) of the river, as was the recruitment of brown trout to the angling stock. In Barrow’s goldeneye, which uses both the lake
and the river, dispersion of adults in spring and young in August was influenced by the availability of aquatic insects in
each habitat. The dispersion of Barrow’s goldeneye tracks the availability of aquatic insects in each of these two main habitats.
Introduced Amercian mink, Mustela vison, may have affected spring numbers and dispersion of harlequin ducks, but the evidence was not conclusive. Numbers of both
duck species and the trout (as CPUE) were relatively stable, although a sharp drop in numbers followed by slow recovery was
observed in Barrow’s goldeneye, and an increase was observed in harlequin ducks in the first year of study. 相似文献
4.
Carolyn G. Palmer Brenton Maart Anthony R. Palmer Jay H. O'Keeffe 《Hydrobiologia》1996,318(3):153-164
The aim of this paper was to investigate the potential for using functional feeding groups (FFGs) as indicators of water quality conditions in rivers, using the Buffalo River, South Africa, as a specific example. Multivariate classification and ordination techniques were used to investigate species and FFG distributions in relation to a number of physico-chemical variables at 16 sites from the headwaters to the estuary of the Buffalo River.Two-way indicator species analysis (TWINSPAN) of species composition ranked most of the sites sequentially down the river, irrespective of water quality conditions. Ordination of FFGs from a set of riffle samples collected in mid-late summer showed only weak relationships between FFG distribution and water quality changes, except where variables changed sequentially down the river (e.g. pH and temperature). Individual species responses to water quality gradients were examined for nine riffle-dwelling species representing diverse FFGs. Following correspondence analysis of a matrix of environmental variables and species frequencies, some species showed strong associations with defined ranges of some variables. In particular, Adenophlebia auriculata (Leptophlebiidae, Ephemeroptera) from the headwater sampling site, was associated with low pH and low temperature. Simulium damnosum occurred under conditions of high turbidity, while Afronurus harrisoni was found under high concentrations of potassium, ammonium and nitrite ions.We conclude that although there was a distinct headwaters fauna in the Buffalo River, and sequential downstream changes in species composition, most FFGs (apart from shredders) were represented down the whole length of the river. FFG classifications are therefore unlikely to provide useful indications of water quality conditions in the Buffalo River.Using a categorical approach to classifying water quality variables, and by applying correspondence analysis to the resulting matrix, we recognised nine species that could be used to define water quality. These indicator species can be used to define tolerance ranges of the fauna for water quality conditions in different parts of the Buffalo river. 相似文献
5.
The present work gives the result of blackfly fauna research of the Slovenský raj (West Carpathians, Slovakia). Our aim was to describe the composition of blackfly communities, find indicator species for communities, describe environmental factors affecting communities and determine the potential changes in species richness. Research was carried out in 2007 and 2008. The presence of 22 species of blackflies was confirmed at 20 sites in the area of Slovenský raj. 12 species were recorded for the first time in this area. The potential for further increase in diversity was calculated by a nonparametric estimation of species richness. Two main groups of sites with their typical blackflies communities were indentified using a TWINSPAN analysis. The presence of Simulium ornatum, S. variegatum and S. argyreatum was typical in larger streams in broad valleys. The absence or low abundance of these species was typical for smaller streams in canyons. Based on the species composition of blackflies communities, we identified 6 groups of sites: 1. anthropogenically disturbed submountain rivers (typical species: Simulium ornatum, S. reptans, S. equinum), 2. undisturbed metarhithral (typical species: Simulium bertrandi, S. codreanui, S. costatum, S. vernum, S. argenteostriatum, S. degrangei, S. argyreatum, S. variegatum), 3. undisturbed hyporhithral (typical species: Simulium trifasciatum, S. tuberosum), 4. undisturbed epirhithral (typical species: Prosimulium hirtipes, P. rufipes), 5. hypocrenal (typical species: Simulium cryophilum, S. monticola) and 6. anthropogenically disturbed epirhithral (typical species: Simulium brevidens, S. maximum). The most important environmental factors explaining differences in species composition like altitude, flow speed, pH, conductivity, oxygen saturation, sulphates concentration and presence of riparian vegetation were identified by the CCA analysis. 相似文献
6.
The present study is the first report of fingerprinting in blackflies (Diptera: Simuliidae), using inter-simple sequence repeat
(ISSR) markers. Among five primers tested, three tetranucleotide repeat primers ((GACA)4, (ACTG)4, (ACAG)4) generated a high proportion of polymorphic bands. Seven species representing various genera, subgenera or species groups
were compared. No similar profiles were found. Intraspecific and interspecific banding patterns were analysed for two species
in the Prosimulium hirtipes (Fries, 1824) species group and four species in the Simulium variegatum (Meigen, 1818) species group. The UPGMA cluster analysis based on Jaccard’s coefficient demonstrated the intraspecific and
interspecific diversity and the resolving power of the ISSR markers to differentiate blackfly species and populations. In
Simulium maximum (Knoz, 1961), geographically defined populations were successfully discriminated. 相似文献
7.
Recruitment courses of three amphidromous sleeper species, Eleotris acanthopoma, E. melanosoma, and E. fusca, were investigated at the surf zone adjacent to the river mouth and at five stations in the Teima River on Okinawa Island,
Japan. All three species occurred at the surf zone as pelagic larvae with transparent and compressed body, a conspicuous air
bladder, and an emarginated caudal fin. Eleotris fusca (16.0–19.6 mm in standard length: SL) sometimes possessed a vestige of the larval chin barbel and were larger than E. acanthopoma (9.7–13.2 mm SL) and E. melanosoma (11.2–12.8 mm SL). The pelagic larvae were also collected during full tide from the lower reaches of the tidally influenced
area of the river. The pelagic larvae may be carried in and out of the estuary with some tidal fluxes, and they may settle
when they reach the upper tidally influenced area where the salinity becomes extremely low. Body width and pigmentation of
newly settled larvae increased. E. fusca was considered to migrate upstream to the freshwater area against the flow of the river just after reaching the settled stage.
After settlement, all three species became completely pigmented, the caudal fin became round in shape, and the fin ray counts
became complete with growth. Also, E. acanthopoma dispersed widely to the lower part of the tidally influenced area or to the lower reaches of the freshwater area, E. melanosoma dispersed to the lower part of the tidally influenced area, and E. fusca dispersed upstream. 相似文献
8.
Summary The impacts of five consecutive treatments of blackfly larvicides on macroinvertebrates in the middle Orange River were assessed. The abundance of the midge Xenochironomus sp. and the limpet Burnupia sp. was lower at sites treated with Bacillus thuringiensis var. israelensis (B.t.i.) compared to control sites (P<0.05). There was no medium-term impact on the abundance of two B.t.i.-sensitive taxa: Simulium spp. and the midge Rheotanytarsus fuscus. Repeated applications of the organophosphate temephos (AbateR 200EC) significantly reduced the abundance of 25% of the invertebrate taxa in the stones-in-current biotope (P<0.1). The most affected taxa were R. fuscus, certain Baetis spp. mayflies and Coenagrionidae damselflies. Ordination of the species/sample matrix using detrended correspondence analysis showed that changes in invertebrate abundance and composition caused by either larvicide were well within the range of natural seasonal and spatial variation. However, the control programme may be detrimental to non-pest blackfly species, particularly the South African endemic Simulium gariepense, which may be endangered because of river regulation. It is concluded that the medium-term impacts of operational dosages of B.t.i. and temephos are safe provided that the recommended dosages of temephos are adhered to, and provided certain sections of river are left untreated as refugia for sensitive taxa. 相似文献
9.
Distribution,community structure and production of fishes in the upper Speed River,Ontario: a preimpoundment study 总被引:6,自引:0,他引:6
Synopsis The upper Speed River, on which a dam was under construction, was surveyed through fourteen qualitative and six quantitative
collections to determine the distribution of fishes in the river above Guelph, Ontario and in a tributary, Luteral Creek.
At the quantitative localities the removal method was used to estimate density and standing crop of all species. At three
of these localities age and growth of the dominant species were determined and total ecological production calculated.
Two approaches to the estimation of production for the 0–1 age class were compared and found to result in differences of 33–39%
in the estimates of total production, thus illustrating the extent to which methodology may affect such estimates
The dominant species in the river were, Semotilus atromaculatus, Notropis cornutus, Pimephales notatus, Rhinichthys atratulus, Hypentelium nigricans, Catostomus commersoni,
Ambloplites rupestris, Micropterus dolomieui and Etheostoma flabellare. Density ranged from 11126 to 74765 individuals per hectare and standing crop from 32.4 to 190.0 kg ha−1. Production values at the three localities were 15, 19 and 54 kg ha−1 yr−1 , and are low compared with estimates for other fluvial systems. Comparison with a 1951 survey of the Speed River revealed
considerable changes in the composition and distribution of fish species. The ranges of several cold-water species had contracted
towards the headwaters, whereas several warm-water species had extended their ranges up the river 相似文献
10.
Impact of human activities on stonefly (Insecta,Plecoptera) ecological metrics in the Hron River (Slovakia) 总被引:1,自引:0,他引:1
Il’ja Krno 《Biologia》2007,62(4):446-457
A total of 57 stonefly species have been recorded in the Hron River. The natural gradient (slope and stream width) and pollution
gradient of the river were defined using CCA based on physical, chemical and stonefly data. Stonefly metrics (abundance, richness/diversity,
sensitivy/tolerance and functional metrics) were used to estimate the quality of the Hron River and the degree of proximity
to its natural state. Similar results were obtained using two different methods. The first method was based on the homogeneity
of variance and the interquartile range of different groups of stretches of the Hron River and the second was based on deviations
from the expected values of biological metrics in a given stretch of the river. These values continuously decreased with increasing
distance from the spring area, with the exception of the saprobic index, which increased in a downstream direction, and the
stonefly average score, which did not change significantly along the whole river flow. The Stonefly Average Score (SAS) metric
is universal for a variety of habitats such as the Hron River upstream and downstream, and is a reliable indicator of water
quality and the natural course of a stream. 相似文献
11.
Jana Porhajašová Vladimír Petřvalský Zbyšek Šustek Jana Urminská Peter Ondrišík Jaroslav Noskovič 《Biologia》2008,63(6):1184-1195
In 2001–2006, ground beetles were pitfall-trapped in a temperate lowland area of South Slovakia in an experimental field divided
in five plots fertilized by four different doses of manure or biosludge (25 t stable manure ha−1, 50 t biosludge ha−1, 50 t stable manure ha−1, 100 t biosludge ha−1 and without fertilization). The field was subsequently sown by spring barley, sugar beat, maize, sunflower, sugar beat and
maize. The ground beetle assemblage consisted of 31 species, but only five species predominated: Pseudoophonus rufipes representing 82.6% of individuals and five species (Poecilus cupreus, Carabus scheidleri, Calathus fuscipes, Trechus quadristriatus, Pterostichus melanarius, Anchomenus dorsalis,
Dolichus halensis) representing together 14.5% of individuals. Pseudophonus rufipes represented 81.7% of dry biomass and three species (Carabus scheidleri, Poecilus cupreus Pterostichus melanarius) 15.9% of biomass. There was no significant influence of organic fertilizing on assemblage structure. During the investigation,
the number of individuals and their biomass increased in all plots until 2003 and than dropped to the starting values. The
culmination of 2003 was preceded by a warmer and more humid season in 2002. After a cold and dry season of 2003 abundance
decreased approximately to starting values. Simultaneously, the local maxima and minima of occurrence of ground beetles in
individual plots shifted independently on the doses of organic material. At the same time, number of occurring species slightly
decreased. The observed changes obviously represent part of long-termed fluctuations in wider surroundings. 相似文献
12.
Neusa Hamada Vanderly Andrade-Souza Marcela De Paul Jeane Marcelle Cavalcante Nascimento 《Medical and veterinary entomology》2023,37(1):47-62
Problems related to the identity of Simuliidae species are impediments to effective disease control in Amazonia. Some of these species, such as Simulium oyapockense Floch & Abonnenc, 1946 (Diptera: Simuliidae), are vectors of the organisms that cause onchocerciasis and mansonellosis diseases. This blackfly species has a wide distribution in South America, and it is suspected of being a complex of cryptic species. The aim of this study is to characterize the nominal species S. oyapockense using partial COI gene sequences. Seven populations of S. oyapockense (morphologically identified) were analysed, including one from its type-locality. The other six populations were collected in Brazil and in Argentina. A taxon collected in Amazonas state, Brazil, with adults similar to S. oyapockense but with distinct pupae, was also included in the analysis (Simulium ‘S’). The nominal species S. oyapockense is circumscribed, and its geographical distribution is restricted to areas north of the Amazon River. Populations of S. oyapockense s.l. collected south of the Amazon River comprise a species complex that needs to be evaluated using integrative taxonomy. Simulium ‘S’ represents a species with unique morphological and molecular characteristics. Distinguishing cryptic species is a prerequisite for reducing the taxonomic impediment, especially in medically important taxa. 相似文献
13.
《African Journal of Aquatic Science》2013,38(2):261-269
Blackfly larvae typically occur in fast-flowing riffle sections of rivers, with different blackfly species showing preferences for different hydraulic conditions. Very little quantitative data exist on hydraulic conditions linked to the blackfly species occurring in South African streams. Stones-in-current biotopes (i.e. fast riffle flows over cobbles) were sampled from four sites in three small clear streams in the Eastern and Western Cape provinces of South Africa. Mean water column velocities at each sampled stone were measured using a mini current meter, while flow velocities closer to the boundary layer where blackfly larvae occurred were estimated using indirect techniques (standard hemispheres and aerating tablets). Standard hemispheres were also used to calculate more complex hydraulic parameters such as Froude and Reynolds numbers. Four species of Simuliid were sampled in sufficient numbers to show trends in flow velocity preferences. Simulium impukane and S. rutherfoordi both occurred at their highest densities at velocities of 0.3m s?1, while S. merops preferred velocities of 0.7m s?1. Simulium nigritarse SL attained the highest densities of all the blackfly species sampled, and its relative abundances were greatest at velocities of 0.8–0.9m s?1. Within the streams surveyed, all blackfly species occurred in subcritical-turbulent flows — based on a classification using Froude and Reynolds numbers — although two of the species were also found in high densities in supercritical flows where these existed at the sites. Local hydraulics within the stones-in-current biotope are complex, but in the absence of fine-scale equipment for measuring micro-velocities, standard hemispheres are a useful, cost-effective technique for the initial quantification of hydraulic parameters in small, clear streams. Such an approach facilitates further understanding of links between hydraulics and aquatic invertebrates in South African streams. 相似文献
14.
Marek Svitok 《Biologia》2006,61(5):547-554
Mayflies were sampled from eleven sites in six tributaries of the upper Hron River. Mayfly communities were ordinated and
related to environmental factors using multiple regression and principal component analysis. Communities of headwater sites
were dominated by Rhithrogena iridina which was gradually replaced by Baetis alpinus, at the lower reaches. Total mayfly species richness was inversely related to stream slope and overall abundance was inversely
related to altitude. The prominent factor influencing mayfly communities was a complex longitudinal gradient as proposed by
the river continuum concept. There were no significant differences in community composition and structure between the left-and
right-hand tributaries of the Hron River. 相似文献
15.
Blackfly larvae were sampled monthly from two smallNeotropical mountain streams 500 m apart from each other in northernVenezuela during a 15-month period, and ten habitat variables weremeasured at two altitudes (800 and 900 m) to determine local spatialand temporal variations in abundance, stream variables, speciesco-occurrence, and substrate preference within the blackflyguild. The blackfly species composition of each stream was the same,with five species (in order of abundance): Simulium ochraceumWalker s.l., S. paynei Vargas, S. metallicum Bellardicytospecies E, Simulium sp., and S. horacioi Okazawa &Onishi. There were clear differences in community structurebetween streams (not among altitudes), although S. ochraceums.l. was the most abundant species in both habitats. Principal component andcorrelation analyses revealed that structural (great depth, width,flow, and discharge) and chemical (low conductivity) factors werethe stream variables best associated to the spatial distribution ofmost blackfly species. Blackfly abundance was greater in the largerstream. Larvae were most abundant on submerged rocks and fallenleaves, although the patterns of substrate use within the guildrevealed substrate partitioning among most blackfly species.There was one general annual peak of abundance at the end of therainy season. We suggest that blackfly community structure in theseNeotropical headwaters streams, over the small spatial scaleexamined here, is largely influenced by interactions among streamsize and velocity-related factors (width, streamflow, discharge andsubstrate availability-stability) and the rainfall regime. 相似文献
16.
J. W. Moore 《Hydrobiologia》1977,54(3):201-208
The ash free dry weight of algae in the plankton, epilithon and gut of predominant herbivores was determined between June
1975 and July 1976 in 2 subarctic Canadian rivers (Baker Creek, Yellowknife River). Algae usually represented < 1% of suspended
solids in both rivers and up to 8o% of material attached to rocks. While they were never found in the gut of rotifers and
copepod nauplii in Baker Creek, they accounted for 0.5% of the contents of the planktonic conchostracon Lynceus brachyurus. Due to the inpalatable colonial structure of most attached algal species, the zoobenthos (mainly mayfly nymphs) contained
only a few cells. Size selection against large fragments of detritus resulted in increased consumption of algae (5–13%) by
Simulium venustum, S. decorum and S. arcticum. In the Yellowknife River, Diaptomus ashlandi (CIII–CVI stages) and Holopedium gibberum contained only a few (30–50) algal cells during summer. Because of size selection, large algae were not ingested by these
species. The inpalatability of colonial algae greatly reduced consumption in the predominant zoobenthic species, Ephemerella coxalis and E. margarita. While all species digested diatoms, the Chlorophyta usually passed through the gut unharmed. It is concluded that algae
are not an important energy source for invertebrates in either stream. 相似文献
17.
Two blackfly species Simulium (Cerqueirellum) oyapockense Floch & Abonnenc and S. (Hemicnetha) seriatum Knab are recorded from Argentina, representing the most southern register for both species. S. oyapockense is a species epidemiologically very important, as a vector of onchocerciasis in the Amazonian focus. Both species are described and illustrated and their distribution are reported, in similarity to others like S. roraimense Nunes de Mello and S. ganalesense Vargas et al. in reference to S. oyapockense and S. mexicanum Bellardi similar to S. seriatum are discussed. 相似文献
18.
D. A. Boakye C. Back G. K. Fiasorgbor A. P. P. Sib Y. Coulibaly 《Medical and veterinary entomology》1998,12(4):345-358
Abstract .During the decade from 1984 to 1993, nine species of the Simulium damnosum complex of blackflies (Diptera: Simuliidae) were identified from the area covered by the Onchocerciasis Control Programme. These were S. damnosum s.s., S. dieguerense, S. konkourense, S. leonense, S. sanctipauli, S. sirbanum, S. soubrense, S. squamosum, and S. yahense. Some of these species were found to consist of two chromosomal variant populations. These were S. konkourense‘Konkouré' and ‘Menankaya' forms, S. sanctipauli sensu stricto and‘Djodji' form, S. soubrense‘Chute Milo' and ‘Beffa' forms. The distribution of these twelve cytological taxa was assessed in relation to the two main vegetation zones of West Africa (forest and savanna), topography, river size and other factors. The range of each species was influenced by seasonal climatic changes in wind movement and river water level. The most widely distributed species were S. sirbanum and S. damnosum s.s., associated with savanna areas, recorded from all river basins. Simulium dieguerense was restricted mainly to Western Mali on the Rivers Bafing and Bakoye in the Senegal River basin. Simulium squamosum was identified from rivers draining mountainous areas in both the forest and savanna zones. Simulium yahense was found in small permanent rivers along a wide forested band parallel to the coast and was absent from the plains of Togo and Benin. Members of the S. sanctipauli subcomplex had restricted distributions except for S. sanctipauli s.s., which was widespread in large rivers of the forest zone from Sierra Leone to the Volta Lake in Ghana. Simulium soubrense‘Beffa' form occurred in Togo and Benin, S. soubrense‘Chutes Milo' form in Guinea, both ‘Konkouré' and ‘Menankaya' forms of S. konkourense occurred predominantly in Guinea and S. leonense in Sierra Leone. The relevance of the distribution maps and the importance of the data bank to vector control larvicidal operations are discussed. 相似文献
19.
Microorganisms are known to play fundamental roles in the biogeochemical cycling of carbon in the coastal environments. To
get to know the composition and ecological roles of the archaeal communities within the sediments of the Pearl River Estuary,
Southern China, the diversity and vertical distribution of archaea in a sediment core was reported based on the 16S rRNA and
mcrA genes for the first time. Quantitative PCR analysis revealed that archaea were present at 106–107 16S rRNA gene copies/g (wet weight) in the sediment core, and the proportion of mcrA versus 16S rRNA gene copies varied from 11 to 45%. 16S rRNA gene libraries were constructed and analyzed for the top layer
(0–6 cm), middle layer (18–24 cm), sulfate-methane transition zone (SMTZ, 32–42 cm), and bottom layer (44–50 cm) sediments.
The results indicated that Miscellaneous Crenarchaeotal Group (MCG) was the main component in the sediments. The MCG archaea
could be further divided into six subgroups: MCG-A, B, C, D, E, and F. On the other hand, mcrA sequences from methanogens related to the order Methanomicrobiales and ANME-2 methanotrophs were detected in all sediment layers. Taken together, our data revealed a largely unknown archaeal
community in which MCG dominated within the Pearl River estuarine sediments, while methanogens and methane-oxidizing archaea
putatively involving in methane metabolism, were also found in the community. This is the first important step towards elucidating
the biogeochemical roles of these archaea in the Pearl River Estuary. 相似文献
20.
The Aouali and Damour watersheds include the main river systems of southern Lebanon. Seven species of Simuliidae were collected from 27 sampling stations along these streams. Simulium nihan. sp. is described; it is related to the species of the monticola‐group. Three species have a restricted distribution within these streams, two of them being crenobiont. The others extend over wide altitudinal and ecological ranges. Eusimulium latizonum, Wilhelmia pseudequina and Simulium nitidifrons are the dominant species of the black‐fly community. 相似文献