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61.
We investigated whether biting midges in peridomestic environments are affected by environmental management practices and the presence of domestic animals. We used CDC light traps to collect midges in 112 residences across 24 locations along tourism routes of Maranhão, Brazil. The collection areas were characterized as follows: i) peridomestic area with domestic animals and without management (dirty); ii) peridomestic with domestic animals and management (clean); iii) peridomestic without animals and with management (clean); iv) peridomestic without animals and without management (dirty). The first two treatments had higher biting midge species richness and abundance, respectively. Generalized linear models indicated a positive correlation between the presence of domestic animals and midge abundance, with an approximate four‐fold increase in Culicoides (Diptera: Ceratopogonidae) abundance in peridomestic areas with animals. The same model showed that domestic animals have no influence on richness. Environmental management does not appear to influence species richness or abundance of biting midges.  相似文献   
62.
Abstract. The semiochemicals carbon dioxide (CO2) and l-octen-3-ol (octenol) were evaluated as attractants at several release rates, alone and in combination, for the major coastal species of biting midges in Georgia: Culicoides furens, C.hollensis and C.melleus (Diptera: Ceratopogonidae). The data show that CO2 is an effective attractant for the females of all three species, but each has a different response pattern. In contrast, octenol was an effective attractant only for C.furens , either alone or in combination with CO2; octenol had a repellent effect on the other two species. The combination of octenol and C02 had a synergistic effect on the collections of C.furens.  相似文献   
63.
Abstract. In 1991, as part of an epidemiological study of bluetongue viruses (BTV) in the Central American and Caribbean region, eight farms located in Costa Rica, Honduras, Panama and Puerto Rico were sampled for Culicoides spp. attacking cattle. Using cattle bait, 3884 biting midges were collected with an electric aspirator during both crepuscular periods. The predominant species captured was Culicoides insignis Lutz (95%), followed by C.furens (Poey) (3.4%), C.filarifer Hoffman/ C.ocumarensis Ortiz (0.9%), C.lahillei (Iches) (0.7%), C.arubae Fox and Hoffman (<0.1%) and C.gorgasi Wirth and Blanton (<0.1%). Blood-engorged specimens from some of these species were collected and comprised: 18% of all C.insignis , 36% of C.furens , 37% of filarifer/ocumarensis and 25% of C.lahillei. No engorged C.arubae or C.gorgasi were caught. These results confirm earlier findings pointing to C.insignis, C.furens and C.filarifer/ ocumarensis as potential vectors of BTV in the region.  相似文献   
64.
Pupa, and adult male and female of Culicoides pseudosimilis n. sp., and pupae of two known species, C. selangorensis Wirth & Hubert, and C. dryadeus Wirth & Hubert, are described and illustrated. An identification key to the Indian species of Clavipalpis and Shermani species group of male Culicoides is also provided.  相似文献   
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We investigated the floral characteristics, floral biology and floral visitors of the six Bornean Tacca species: T. bibracteata (only floral characteristics), T. borneensis, T. havilandii, T. leontopetaloides, T. palmata and T. reducta, and T. cristata from Peninsular Malaysia. All species are protogynous with pollen strings extruded post flower opening. Blooming of all species started from dawn except for T. leontopetaloides which flowered from dusk. While T. borneensis, T. cristata, T. havilandii, T. leontopetaloides and T. reducta are facultatively autogamic as the pollen/ovule ratios (P/O ratios) were low, T. bibracteata is facultatively xenogamic as its P/O ratio was higher. Four species (T. borneensis, T. cristata, T. havilandii and T. reducta) were tested for autonomous self-pollination but all failed to set fruit. Manual self- and cross-pollination treatments of T. borneensis, T. cristata and T. havilandii showed reduced fruit set and seed set. In contrast, T. reducta was highly self-compatible. The showy bracts and bracteoles of T. borneensis are needed to guarantee pollination success but is not so in the other species investigated. Tacca are pollinated by two pollination guilds of female midges: two species of Forcipomyia (Lasiohelea) and Culicoides hinnoi. The floral biology and mating system of Tacca species indicate that most fruits and seeds were produced in samples resulting from natural pollination.  相似文献   
68.
ABSTRACT

Ablabesmyia

is a speciose genus, with about 90 species distributed worldwide, 37 of which occurring in the Neotropical region. In Colombia, A. metica is the only species of the genus recorded so far, which was initially described with material collected in the Colombian Orinoquia and more recently recorded in the southeastern Brazil. In the present study, Ablabesmyia opita sp. n. from the Colombian Andes is described and illustrated based on adult males collected at the inter-andean valley of Magdalena river basin. In addition, an updated taxonomic key for Neotropical species and a map of Ablabesmyia records in Colombia are provided. The male of the new species is similar to that of A. laurindoi but can be easily distinguished by the coloration patterns of the legs, the shape of the sternapodeme and by the number of antepronotals.

http://www.zoobank.org/urn:lsid:zoobank.org:pub:A9FD43D5-7018-4B3F-925B-E843B82D71E6  相似文献   
69.
The species diversity and seasonal abundance of biting midges of the genus Culicoides (Diptera: Ceratopogonidae) were studied in northwestern Argentina during the period 2003–2005. A total of 5437 Culicoides specimens were collected using CDC light traps in three areas of the mountainous rainforest area. The most common species were Culicoides paraensis (Goeldi) and C . insignis Lutz, Culicoides lahillei (Iches), C . venezuelensis Ortiz & Mirsa, C . debilipalpis Lutz and C . crescentis Wirth & Blanton were also collected. Culicoides paraensis was abundant during the summer, and C . insignis and C . lahillei during late summer and early fall. Accumulated rainfall was the climatic variable most related to fluctuation in abundance of C . paraensis .  相似文献   
70.
Deformities in the mouthparts of larval Chironomidae, particularly of the teeth on the mentum, have been proposed as a bioindicator of sediment quality and environmental stress. Most work to date has concentrated on relatively few abundant, responsive genera common in soft-bottom lakes. We examined mentum deformities in 25 genera of Chironominae, Orthocladiinae and Diamesinae (one genus) from streams and a lake in rural Nova Scotia where farming and forestry are the principal land uses. Incidence of deformity at similar stream sites varied across genera from zero to >10%. Average frequencies of deformity across all three subfamilies at sites with no known sources of contamination ranged from <4% to 8%, and increased to nearly 15% at a site receiving treated municipal sewage effluent. Differences in chironomid community structure and rates of leaf litter decomposition above and below the sewage effluent outfall were congruent with the difference in mentum deformities. Frequencies of deformity observed here are an order of magnitude greater than in similar studies of rural areas. Low-level stress from agriculture or forest harvesting may be widespread in rural regions even in aquatic ecosystems that are seemingly free of industrial discharges or sediment contamination.  相似文献   
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