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1.
During 2009–2011, mosquitoes were captured in CDC miniature light traps using CO2 (dry ice) at six sites in the Lower Dyje River Basin (Czech Republic). Other methods of capture — sweeping from vegetation and collection of larvae and pupae from ponds — were also used for more precise diagnostics. Thirty mosquito species of six genera were confirmed. A total of 415,218 females were captured. Most frequently found were the outbreak species Aedes vexans (56.52% of all mosquitoes collected) and Ae. sticticus (16.40%). Among other flood species, Ae. rossicus (5.17%), Ae. cantans and Ae. annulipes (2.44% of all females collected), and Ae. cinereus s. l. (1.11%) were especially abundant. Females of Ae. cataphylla were captured in spring (0.31%) and Ae. intrudens was numerous only at one site. Among the other species, Culex pipiens s. l. (6.61%) and Cx. modestus (8.87%) were abundant. Anopheles maculipennis s. l. (1.01%), An. claviger (0.43%), An. plumbeus (0.08%), An. hyrcanus (0.08%), Coquillettidia richiardii (0.52%) and Culiseta annulata (0.18%) were also detected. Sparsely occurring were Ae. excrucians, Ae. flavescens, Ae. caspius and Ae. geniculatus. Captured only very sporadically were Ae. communis, Ae. leucomelas, Ae. dorsalis, Ae. rusticus, Cx. martinii, Cx. territans, Cs. morsitans and Uranotaenia unguiculata.  相似文献   

2.
Aim We tested the hypothesis that endemism of black flies in the Caucasus of Armenia is reflected in their gut symbiotes, i.e. trichomycete fungi and ichthyosporean protists. Location The study area, Armenia, is a biodiversity hotspot, with high levels of plant and animal endemism. Located in the southern Caucasus, Armenia is a rugged, mountainous, landlocked country of 29,800 km2, with fast‐flowing rivers and little forested land. About half of the 51 species of black flies in Armenia are endemic to the Caucasus. Methods The larvae of 22 species of black flies, including seven endemic to the Caucasus, were collected from 35 sites throughout Armenia, from 1998 to 2004, and assayed microscopically for gut‐inhabiting trichomycete fungi and ichthyosporean protists. Results Nearly 68% of larval black flies in Armenia contained at least one species of gut symbiote, with a mean of 0.9 ± 0.04 species per host larva. Eight species of trichomycete fungi and two species of ichthyosporeans were found in larval guts. Seven of these species were recorded for the first time in Asian black flies. Species accumulation curves showed no additional species of gut symbiotes after 17 host species and 22 sites had been examined. All gut symbiotes were widely distributed, indicating an absence of endemic trichomycetes in the black flies of Armenia. Main conclusions Although the Caucasus Region is noted for its high levels of endemism for plants and animals, including black flies, the gut symbiotes of black flies are all widespread species. The absence of endemic gut symbiotes in larval black flies might be explained by their lack of host specificity; an absence of host specificity would not constrain the geographical distribution of the symbiotes.  相似文献   

3.
4.
Many mycophagous species of Drosophila can tolerate the mushroom poison α-amanitin in wild mushrooms and in artificial diet. We conducted feeding assays with sixteen Drosophila species and α-amanitin in artificial diet to better determine the phylogenetic distribution of this tolerance. For eight tolerant and one related susceptible species, we sequenced the gene encoding the large subunit of RNA Polymerase II, which is the target site of α-amanitin. We found no differences in the gene that could account for differences in susceptibility to the toxin. We also conducted feeding assays in which α-amanitin was combined with chemical inhibitors of cytochrome P450s or glutathione S-transferases (GSTs) in artificial diet to determine if either of these enzyme families is involved in tolerance to α-amanitin. We found that an inhibitor of GSTs did not reduce tolerance to α-amanitin, but that an inhibitor of cytochrome P450s reduced tolerance in several species. It is possible that the same cytochrome P450 activity that produces tolerance of α-amanitin might produce tolerance of other mushroom toxins as well. If so, a general detoxification mechanism based on cytochrome P450s might answer the question of how tolerance to α-amanitin arose in mycophagous Drosophila when this toxin is found in relatively few mushrooms.  相似文献   

5.
Five species are included in the Simulium siolii group, which is placed in the subgenus Psaroniocompsa (Diptera: Simuliidae). Of these five species, only two (Simulium siolii Py-Daniel and Simulium tergospinosum Hamada) have been described in all their life stages, except eggs. Knowledge of the taxonomic characters of all life stages of a species is important in order to clarify interspecific and higher-level taxonomic relationships. The objectives of the present study are to describe the male of Simulium damascenoi Py-Daniel, to provide a list of black-fly species their bionomics and distributions in the state of Amap , Brazil, and to provide an identification key for larvae and pupae for these species.  相似文献   

6.
The ten year research (1995–2004) of adult mosquitoes in the area of Osijek by dry ice baited CDC traps has provided significant information on mosquito species, species prevalence, their dynamics and seasonal activity. A total of 207,136 adult mosquitoes comprising twenty species belonging to the following genera: Anopheles, Ochlerotatus, Aedes, Culex, Coquillettidia, Culiseta and Uranotaenia were collected. The seven most common species collected during this study were: Aedes vexans (75.6%), Ochlerotatus sticticus (13.3%), Culex pipiens complex (5.9%), Anopheles maculipennis complex (1.9%), Oc. cantans (0.9%), Oc. caspius (0.6%) and Oc. excrucians (0.6%). The temporal changes in the relative abundance of the twenty mosquito species in the Osijek area were reflected in three peaks: in May, July and September. Seasonal population dynamics differed between years and between mosquito species in relation to wetland, urban and forest habitats and was influenced by water level of the Drava and the Danube rivers.  相似文献   

7.
The abundance, generation time and production ofChironomus salinarius larvae in a lagoon fish-pond system in the Bay of Cádiz were studied by taking monthly samples at 3 sites during 1991 and 1992. Numerical abundance and biomass of larvae showed considerable spatial, seasonal and interannual variation (ANCOVAs,P<0.001). The maximum mean annual density was 7048 larvae m–2, and corresponded to a biomass of 3.08 g dry weight (DW) m–2. It was recorded at the site with the lowest rate of water renewal. Seasonal patterns were similar at all sites, with main annual peaks of abundance and biomass in autumn-early winter. Chironomid density was positively related to the biomass of benthic macroalgae (P<0.001). The population studied was multivoltine with a probable average of five generations per year, with overlapping cohorts and a predominance of third- and fourth-instar larvae. Estimates of annual production ranged between 72.2 g DW m–2 yr–1 at the site with the lowest rate of water renewal in 1991 and 0.1 g DW m–2 yr–1 at the site with the highest rate of water renewal in 1992. Mean annual production and the production/biomass ratio for the system was estimated to be 16.8 g DW m–2 yr–1 and 12.7, respectively. Possible factors leading to the observed density fluctuations are discussed, as well as possible sources of error in production estimates.  相似文献   

8.
Evaluating the influences of LUCC (Land Use/Land Cover Change) on landscape pattern is significant for understanding and improving ecological environment system management. This study used landscape pattern as an important indicator to estimate the impacts of the LUCC in the Yangtze River Basin from 2001 to 2019. Based on the remote sensing images of LULC (Land Use/Land Cover) in the Yangtze River Basin in 2001–2019, the dynamic attitude and transfer matrix of LULC, and landscape pattern indices were employed to analyze the LUCC and the impact of LULC on the landscape pattern of the Yangtze River Basin. The results of LUCC show that the main LUCC in the Yangtze River Basin during 2001–2019 is mainly manifested by the increase of water body, forest, wetland, crop/natural vegetation mosaic (NVM) and urban, among which the forest increased the most by 62,635 km2. The areas of grassland and cropland are decreasing, with the grassland decreasing the most. Forest, crop/NVM and cropland are transformed into grassland, which complements the lack of grassland to some extent. LUCC in the Yangtze River Basin is most intense between grassland and forest. Landscape pattern shows: Grassland occupies an important advantage in the whole landscape structure. Forest, grassland and urban landscapes are seriously fragmented, and their LSI (Landscape Shape Index) is more complex than others. The connectivity between various landscape types is weakened, and the degree of landscape fragmentation is increased, but the LULC structure is becoming more and more abundant. The areas with high landscape fragmentation value have richer landscape diversity and diverse LULC types. There is a strong correlation between grassland and the four landscape pattern indices. The change of landscape pattern in the Yangtze River Basin is influenced by natural factors and LUCC in the Yangtze River Basin, and the change caused by human activities is the main driving factor of LUCC.  相似文献   

9.
Water represents the major component of most food systems. During thermal or high-pressure processing, physical and chemical properties of water are changed. The p–T diagram represents an obvious presentation of isoproperty lines and their pressure and temperature dependencies. In this work, 15 different properties of pure water are shown as isoproperty lines in the pressure–temperature landscape. By using functional relationships from the “International Association for the Properties of Water and Steam” and databases from the “National Institute of Standards and Technology,” highest accuracy is guaranteed. Applying the generated graphs, a compact overview is given and a wide range of thermal and high-pressure processes can easily be compared. The different pressure and temperature dependencies of all properties showed the complexity of medium conditions during thermal and high-pressure processing. An extended understanding of pressure–temperature dependencies will improve process concepts as well as industrial applications at high temperature and high isostatic pressure.  相似文献   

10.
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   

11.
Abstract

An overview of the development of the field of psychology in Estonia, beginning with the founding of the university in 1632 and up to 1940.  相似文献   

12.
The European black fly Simulium (Simulium) colombaschense (Scopoli), once responsible for as many as 22,000 livestock deaths per year, is chromosomally mapped, permitting its evolutionary relationships and pest drivers to be inferred. The species is 12 fixed inversions removed from the standard sequence of the subgenus Simulium. Three of these fixed inversions, 38 autosomal polymorphisms, and a complex set of 12 X and 6 Y chromosomes in 29 zygotic combinations uniquely characterize S. colombaschense and reveal 5 cytoforms: ‘A’ in the Danube watershed, ‘B’ in Italy’s Adige River, ‘C’ in the Aliakmonas River of Greece, ‘D’ in the Aoös drainage in Greece, and ‘E’ in the Belá River of Slovakia. ‘C’ and ‘D’ are reproductively isolated from one another, and ‘B’ is considered a cytotype of ‘A,’ the probable name bearer of colombaschense. The species status of ‘E’ cannot be determined without additional collections. Three derived polytene sequences, based on outgroup comparisons, place S. colombaschense in a clade of species composed of the S. jenningsi, S. malyschevi, and S. reptans species groups. Only cytoforms ‘A’ and ‘B’ are pests. Within the Simuliidae, pest status is reached through one of two principal pathways, both of which promote the production of large populations of blood-seeking flies: (1) colonization of the world’s largest rivers (habitat specialization) or (2) colonization of multiple habitat types (habitat generalization). Evolutionary acquisition of the ability to colonize large rivers by an ancestor of the S. jenningsi-malyschevi-reptans clade set the scene for the pest status of S. colombaschense and other big-river members of the clade. In an ironic twist, the macrogenome of S. colombaschense reveals that the name associated with history’s worst simuliid pest represents a complex of species, two or more of which are nonpests potentially vulnerable to loss of their limited habitat.  相似文献   

13.
《Journal of Asia》2020,23(1):124-131
Predation and cannibalism can affect the co-existence of mosquito species or the assemblage of mosquito species (i.e., community structure). In this study, predatory feeding patterns and cannibalism of larvae of Armigeres subalbatus mosquitoes were quantified under laboratory conditions using Aedes albopictus and Culex uniformis larvae as prey organisms. Rate of consumption of prey larvae and the rate of cannibalism of 1st to 4th instar larvae of Armigeres subalbatus were reported at 24 h intervals with and without alternative food supplement. Both the 3rd and 4th instar larvae of Ar. subalbatus showed a substantial predation on the larvae of Ae. albopictus (33.6 ± 4.4) and Cx uniformis (47.3 ± 7.6). The cannibalism of the predatory larvae was strongly correlated to the larval density (r = 0.9). The predator and the prey density and the given food type were significant factors that determined the rate of pupation, death and the emergence as adults. A significant relationship was shown for the co-occurrence of predatory larvae and the prey larvae at the 85 natural breeding habitats observed at the field (χ2 = 74.4, p < 0.001). Nine breeding sites (10.6%) were positive for both prey and predatory larvae. Our study showed robust information about the predatory and cannibalistic behavior of Ar. subalbatus larvae emphasizing their role in managing the population structure of mosquito communities.  相似文献   

14.
15.
Climate change alters regional water and carbon cycling, which has been a hot study point in the filed of climatology and ecology. As a traditionally “water-rich” region of China, Yangtze River Basin plays an important role in regional economic development and ecosystem productivity. However, the mechanism of the influence of climate change on water and carbon cycling has been received little attention. As a coupling indicator for carbon and water, the water use efficiency (WUE) is widely used, which indicates the water consumption for carbon sequestration in watershed and regional scale. A lot of studies showed that climate change has significantly affected the water resource and production of the ecosystems in Yangtze River Basin during the period of 1956–2006, when great climate variations were occurred. To better understand the alternation pattern for the relationship between water and carbon cycling under climate change at regional scale, the WUE and the spatiotemporal variations patterns were simulated in the study area from 1956 to 2006 by using the Integrated Biosphere Simulator (IBIS). The results showed that the WUE spatial pattern had the annual and seasonal variations. In general, the average annual WUE value per square meter was about 0.58 g C/kg H2O in Yangtze River Basin. The high WUE levels were mainly distributed in the eastern area of Sichuan, western area of Jiangxi and Hunan, and the highest value reached 0.88 g C/kg H2O. The lowest WUE’s were mainly located in the western area of Sichuan and Qinghai with the lowest values reaching to 0.36 g C/kg H2O. The WUE in other regions mostly ranged from 0.5 to 0.6 g C/kg H2O. For the whole study area, the annual WUE slowly increased from 1956 to 2006. The WUE in the upper reaches of Yangtze River increased based on the simulated temporal trends, which mainly located in the western area of the Sichuan Basin; the WUE of the middle reaches of Yangtze River had increased slightly from 1987 to 1996, and then decreased from 1996 to 2006; the lower reaches of Yangtze River always had smaller WUE’s than the average from 1956 to 2006. The spatiotemporal variability of the WUE in the vegetation types was obvious in the Yangtze River Basin, and it was depended on the climate and soil conditions, and as well the disturbance in its distribution areas. The temporal variations of WUE among different vegetation types had similar trends but different in values. The forest type had higher WUE than any other vegetation types ranging from 0.65 to 0.8 g C/kg H2O. The WUE of shrubland ranged from 0.45 to 0.6 g C/kg H2O. The WUE of tundra was the lowest, indicating the differences in plant physiology. The consistence of the spatial pattern of WUE with the NPP indicated that the regional production of Yangtze River Basin increased based on the water resources prompted and vegetation restoration. We found the drought climate was one of critical factor that impacts the alteration of WUE in Yangtze River Basin in the simulation.  相似文献   

16.
Organisms with vast distributions often represent geographical mosaics of cryptic species. The black fly Simulium (Wilhelmia) lineatum is among the most widely distributed members of the family Simuliidae, ranging from the British Isles to eastern China. Rather than viewing S. lineatum as a possible aggregate of multiple species, taxonomists have suggested a more inclusive taxon with additional synonyms. Accordingly, S. lineatum is an ideal candidate for testing the hypothesis that a wide geographical distribution signals the presence of more than one species. A cytogenetic approach was used to probe the macrogenome of S. lineatum and other taxa proposed by taxonomists as conspecific. The banding patterns in the polytene chromosomes of 480 larvae from 15 countries across the Palearctic Region revealed 128 rearrangements of the complement. All rearrangements were autosomal and 89% were inversions nonrandomly distributed among species and among chromosome arms. The analyses clarify long‐standing confusion over previously proposed names and reveal a longitudinal succession of four species sequentially replacing one another from west to east: Simulium lineatum s.s., Simulium balcanicum, Simulium turgaicum, and Simulium takahasii. Thus, S. turgaicum is recalled from synonymy and the other three species are validated. Within the most‐represented species, S. balcanicum, the frequency of inversions follows a longitudinal gradient with a north–south bias; as the distance between the sites increases along this north‐west–south‐east axis, the similarity of inversion frequencies between sites decreases. Validation of the concept that broadly distributed black flies are composites of structurally similar species provides a framework for guiding discovery of additional biodiversity. © 2014 The Linnean Society of London, Biological Journal of the Linnean Society, 2014, 114 , 163–183.  相似文献   

17.
Climate change alters regional water and carbon cycling, which has been a hot study point in the filed of climatology and ecology. As a traditionally “water-rich” region of China, Yangtze River Basin plays an important role in regional economic development and ecosystem productivity. However, the mechanism of the influence of climate change on water and carbon cycling has been received little attention. As a coupling indicator for carbon and water, the water use efficiency (WUE) is widely used, which indicates the water consumption for carbon sequestration in watershed and regional scale. A lot of studies showed that climate change has significantly affected the water resource and production of the ecosystems in Yangtze River Basin during the period of 1956–2006, when great climate variations were occurred. To better understand the alternation pattern for the relationship between water and carbon cycling under climate change at regional scale, the WUE and the spatiotemporal variations patterns were simulated in the study area from 1956 to 2006 by using the Integrated Biosphere Simulator (IBIS). The results showed that the WUE spatial pattern had the annual and seasonal variations. In general, the average annual WUE value per square meter was about 0.58 g C/kg H2O in Yangtze River Basin. The high WUE levels were mainly distributed in the eastern area of Sichuan, western area of Jiangxi and Hunan, and the highest value reached 0.88 g C/kg H2O. The lowest WUE’s were mainly located in the western area of Sichuan and Qinghai with the lowest values reaching to 0.36 g C/kg H2O. The WUE in other regions mostly ranged from 0.5 to 0.6 g C/kg H2O. For the whole study area, the annual WUE slowly increased from 1956 to 2006. The WUE in the upper reaches of Yangtze River increased based on the simulated temporal trends, which mainly located in the western area of the Sichuan Basin; the WUE of the middle reaches of Yangtze River had increased slightly from 1987 to 1996, and then decreased from 1996 to 2006; the lower reaches of Yangtze River always had smaller WUE’s than the average from 1956 to 2006. The spatiotemporal variability of the WUE in the vegetation types was obvious in the Yangtze River Basin, and it was depended on the climate and soil conditions, and as well the disturbance in its distribution areas. The temporal variations of WUE among different vegetation types had similar trends but different in values. The forest type had higher WUE than any other vegetation types ranging from 0.65 to 0.8 g C/kg H2O. The WUE of shrubland ranged from 0.45 to 0.6 g C/kg H2O. The WUE of tundra was the lowest, indicating the differences in plant physiology. The consistence of the spatial pattern of WUE with the NPP indicated that the regional production of Yangtze River Basin increased based on the water resources prompted and vegetation restoration. We found the drought climate was one of critical factor that impacts the alteration of WUE in Yangtze River Basin in the simulation.  相似文献   

18.
19.
Number of larval instars, age structure and environmental effects on these parameters represent basic information in the study of insect population biology. When species have economic importance, this information is essential in order to choose the best period to apply different control methods and to determine the stages of the life cycle of the insect that are most susceptible to each treatment. The family Simuliidae has many species of medical/veterinary importance in the world, and some studies in the temperate region have suggested that the number of larval instars and the larval size can vary according to the season, gender and some environmental factors, such as temperature and diet. This study, with the zoophilic species Simulium perflavum Roubaud, is the first in the Neotropics observing some of these factors and will serve as a template for other species of medical importance in the region. S. perflavum larvae were collected in five streams in Central Amaz?nia (Manaus and Presidente Figueiredo counties, State of Amazonas), in Sept./Oct. 1996 (dry season) and Feb./Mar. 1997 (rainy season). These larvae were measured (lateral length of head capsule and width of cephalic apodema) to determine the number of larval instars (n=3985), to compare the larval size between seasons and genders (last and penultimate larval instars, n=200). Seven larval instars were determined for this species using frequency distributions, t-tests and Crosbys growth rule. Significant differences were not detected (t-test, p>0.05) in larval size between seasons and genders. Our results differ from some found in temperate regions suggesting that in the Neotropical region the larval size in different seasons and different genders remains constant, although some environmental parameters, such as diet, change depending on the season.  相似文献   

20.
Old World species of the genus Glenanthe are treated comprehensively with an emphasis on the unusually diverse morphological heterogeneity discovered in structures of the male terminalia. As perspective for this treatment, the tribe Lipochaetini, in which Glenanthe is placed, is characterized and discussed, and an annotated key to the four included genera is provided to facilitate their identification. Glenanthe is demonstrated to be a monophyletic lineage within Lipochaetini. Seven Old World species of Glenanthe are now known, including two new Afrotropical species as follows (type locality in parenthesis): G. namibia n. sp. (Namibia. Mukwe: Divuju: Okavango River [18°04’04”S, 21°28’51”E] and G. danielssoni n. sp. (Republic of South Africa. Cape Province: De Hoop Nature Reserve [34°27’S, 28°25’E]. The identity of G. fuscinervis Becker, revised status (raised from synonymy with G. ripicola (Haliday)), is clarified, and found to be conspecific with Hydrina ochracea Oldenberg, which is recognized as a junior synonym. Papp’s synonymy of Glenanthe fasciventris Becker with Hydrellia (Glenanthe) ripicola Haliday is confirmed, and herein we relegate G. iranica Canzoneri & Rampini also as junior synonym of G. ripicola. The remarkable diverse structures of the male terminalia of all included species are described and illustrated and distribution maps are also provided.  相似文献   

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