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1.
189 species of insects from 55 families and 9 orders were found in the Kichiga River basin, northeastern Kamchatka Peninsula in 1987–1994: 7 species of Plecoptera, 7 of Odonata, 1 of Orthoptera, 4 of Homoptera, 6 of Heteroptera, 54 of Coleoptera, 73 of Lepidoptera, 15 of Hymenoptera, and 22 species of Diptera. Most of the insect species present in the Kichiga basin have wide ranges: 55 species and subspecies are Holarctic, 52 species have a broad Palaearctic distribution, 10 are Eastern Palaearctic, 8 are Amphi-Pacific, 8 are circumboreal or circumpolar, 4 are Far Eastern or Pacific; 5 species are endemic or subendemic to Kamchatka or some part of the peninsula.  相似文献   

2.
Chronology of appearance and distribution in the Kamchatka River basin of a new representative of freshwater ichthyofauna on the peninsula—Barbatula toni—is presented. The data are reviewed on its size-weight composition, individual fecundity, and feeding in the floodplain lake Kurazhechnoye (the middle reaches of the Kamchatka River). With consideration of stable reproduction of Barbatula toni it is assumed that in the nearest years its abundance may increase, its distribution in the Kamchatka River basin may expand, and it may penetrate other river systems of the peninsula.  相似文献   

3.
To reveal genetic differentiation and origin of sympatric Lake Kronotskoe charr morphs, we sequenced a fragment of control region (558-bp) and Cytochrome B gene (1015-bp) (combined length 1573-bp) in 232 specimens from the lake and, as an outgroup, 57 specimens from the Kronotskaya River below water-falls (anadromous malma) and 77 specimens from other large water bodies from the Kamchatka. A total of 52 nucleotide positions were polymorphic, and these defined 67 haplotypes. Our data does not allow to estimate genetic differentiation among different lake-dwelling morphs, but strongly supports the monophyletic origin of all morphs within the lake. To estimate genetic differentiation and population structure, an extensive study of microsatellite variation has to be conducted.  相似文献   

4.
1. We investigated the occurrence (presence or absence) of stream‐dwelling Dolly Varden (Salmonidae: Salvelinus malma) in the 78 tributaries of the Sorachi River system, Hokkaido, Japan to examine evidence for metapopulation structure. 2. We hypothesised (i) that the occurrence of Dolly Varden would be less likely in small tributaries because of the higher extinction risk and (ii) that occurrence would be less likely in isolated tributaries because of reduced rates of dispersal and colonisation. In addition to these two general predictions, we hypothesised (iii) that the occurrence would be more likely in spring‐fed tributaries, because Dolly Varden prefer cold water as present in these systems. 3. When all the tributaries were included in a multiple logistic regression analysis, habitat size and habitat type (spring‐fed versus non‐spring‐fed tributaries) were selected for the best model, whereas isolation was not important. However, when tributaries in the lower Sorachi basin (an area likely influenced by human activities) were excluded from the analysis, the effect of isolation became significant. 4. Our results indicate there is a potential metapopulation structure of the Dolly Varden in the Sorachi River basin. Furthermore, it is possible that metapopulation dynamics follow a clinal pattern. In the upper and middle reaches of the Sorachi River basin, an equilibrium between extinction and colonisation of Dolly Varden populations is a possibility. In the lower portion of the basin, isolation appeared to be less important, and extinction rate may be driving patterns of occurrence toward systematic extinction of local populations. 5. Our results illustrate the possibility of spatial variation in the processes influencing occurrence of Dolly Varden within a single river basin, and the potential influences of habitat alteration on extinction and colonisation processes.  相似文献   

5.
Synopsis Crayfish are not native to the Colorado River basin (CRB), however they are now established in portions of the mainstem and in many tributaries. I used density manipulation experiments in a laboratory setting to determine intra- and interspecific competition for food between Orconectes virilis, an aggressive polytrophic crayfish now common in the CRB, and two native fishes: Gila chub, Gila intermedia, and flannelmouth sucker, Catostomus latipinnis. I tested each fish species in separate trials. Growth of Gila chub decreased when animal densities increased, however they were more affected by intraspecific competition than by crayfish presence. In contrast, growth of flannelmouth suckers was more affected by crayfish than by intraspecific competition. Crayfish growth was not significantly altered by presence of either fish. Crayfish thus reduced fish growth by competition for food, but the effect differed markedly between the two species. An erratum to this article can be found at .  相似文献   

6.
Frolov SV 《Genetika》2001,37(3):350-357
The karyotypes of northern Dolly Varden and white char, sympathrically inhabiting the Kamchatka River basin, were studied. The karyotype of Dolly Varden was stable: 2n = 78 and NF = 98 + 2, while in white char, polymorphism and mosaicism for the chromosome number were revealed: 2n = 76-79, NF = 98 + 2. Using a routine chromosome staining technique, the karyotype of white char (2n = 78) was shown to be identical to that of Dolly Varden. In both karyotypes, similar sets of marker chromosomes were present: two pairs of submetacentric (SM), one pair of submeta-subtelocentric (SM-ST), one pair of large acrocentric (A), and one pair of large sub-telocentric (ST) chromosomes. However, the karyotypes of Dolly Varden and white char differed in the number and location of nucleolus organizer regions (NORs). In Dolly Varden, single NORs located in the telomeric regions of the marker SM-ST chromosomes were observed. In white char, NORs were multiple and located both in the telomeric regions of the marker SM-ST chromosomes and on the short and long arms of large ST chromosomes. The identical marker chromosomes indicate considerable phylogenetic relatedness between Dolly Varden and white char from the Kamchatka River basin. Variation in NORs provides evidence for the reproductive isolation of these chars and their species status.  相似文献   

7.
For one of the small Western Kamchatka rivers, according to the combination of several characteristics (watershed, channel slope, water abundance of the flow, pattern of bottom sediments), the classification of channel processes was performed, and on its basis, six biotopes successively replacing each other from the effluents to the mouth were separated. It was shown that against the background of relatively stable conditions of the summer-autumn period, an independent population of Salmonoidei, an assembly, is formed within each biotope. This is manifested in specific features of species composition, size and age structure, and the density of populating biotopes. The stability of the distribution of fish population is supported by constant species composition in particular biotopes over three years and by a comparatively high level of residence of the dominant salmon species.  相似文献   

8.
The paper studies populations of the Dolly Varden charr from some rivers in eastern Kamchatka in 2005–2007. Generally small variability is noted in biological parameters (length, weight, age, and sex composition), however, significant variability is revealed in size of individuals within age groups. Long-period cycles are marked in the dynamics of catches. The periodicity of catches of charr in different areas of east Kamchatka in general terms is the same, which gives reason to summarize the nature of its population dynamics in the whole coast.  相似文献   

9.
Salmon that enter the Kamchatka River are intensively traumatized by lamprey (from 12.0 to 74.0% in different years). An analysis of the frequency distribution of oral disk marks on salmon revealed two types of marks: (1) small (diameter < 2.2 cm, mainly of oval form, located in the middle of the fish in the upper part of the body) and (2) large (diameter > 2.2 cm, of roundish form, located in the front in the lower third of body). The small marks (type I) are mainly left by the Kamchatka lamprey Lethenteron camtschaticum. The second type of trauma is inflicted by large individuals of the Pacific lamprey Enthosphenus tridentatus in the 2nd and 3rd year of marine life. The most typical traumatic injuries caused by lamprey to salmon are described. Injury data are provided for six species of salmon, namely, sockeye, pink, chum, coho, chinook, and char.  相似文献   

10.
Two previously unknown profundal dwelling charr morphs of the genus Salvelinus from Lake Kronotskoe are described in this article. According to their lifestyle peculiarities, these morphs were named the “bigmouth charr” and “smallmouth charr.” The former group is near-bottom benthivorous, while the latter one inhabits the water column and occupies the omnivorous niche. Bigmouth and smallmouth charrs are distinguished from the rest of the sympatric charr morphs by their smaller size, shorter snout, larger eyes, as well as by several craniological traits and lower parasite abundance. Spawning of both morphs takes place directly in the profundal zone and lasts from late October to February. Additional studies are required to determine the systematic status of the new morphs.  相似文献   

11.
Based on the literature and new data, a list of 48 species belonging to 26 genera of 8 stonefly families from the Selenga River basin is presented. Isoperla kozlovi Zhiltzova, I. lunigera Klapálek, and I. obscura (Zetterstedt) are recorded from the Russian part of the Selenga River basin for the first time; Filchneria mongolica Klapálek is new to the Russian fauna.  相似文献   

12.
Frolov SV 《Genetika》2005,41(12):1688-1696
Resident (lacustrine) chars, inhabiting many lakes of Kamchatka, Chukotka, and continental coast of the Sea of Okhotsk, are of particular interest for understanding the mechanisms of speciation and evolution of Salvelinus chars. Since one of these, the char from Dal'nee Lake (Paratunka River basin, southeastern Kamchatka), is substantially different from lacustrine-riverine and anadromous chars from the Paratunka River basin in several morphological traits, hemoglobin spectrum, ecology, and reproduction, it is considered an isolated species Salvelinus krogiusae. The karyotype of the resident char from Dal'nee Lake was shown to be variable in most individuals, containing 76 to 80 chromosomes in different cells, with NF = 98. This suggests that the variability of the chromosome number in this char form is explained by Robertsonian translocations. In females and males, cells with respectively 2n = 78 and 2n = 77 prevailed. Heteromorphic sex chromosomes were not found in the karyotype of this char species. Nucleolar-organizing regions (NORs) were mostly detected in the telomeric regions of short arms of large submetacentric chromosomes. These features of the Krogius char karyotype demonstrate that this species is isolated from other Kamchatka chars, being similar to Taranetz char S. taranetzi from Chukotka Peninsula, which is in good agreement with morphological data.  相似文献   

13.
Results of the long-term faunistic study of Monogenea from fishes of the Chu River basin are reported. Fauna of Monogenea in the studied area was found to include 51 species of 11 genera and 5 families. Thirteen parasite species occurred in the mountain part of the basin, and 40 species inhabit the valley zone, including 10 species of the Amur faunistic complex probably introduced to Kyrgyzstan together with acclimatized fishes.  相似文献   

14.
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16.
Samples of Triassic pelagic limestones collected in several regions of the Central Mediterranean area were examined with the electron microscope. They show calcareous nannoplankton existing already from Middle Triassic time. The Middle Triassic nannofossils are contained in nodular limestones such as the “Ammonitico Rosso” of Epidaurus (Greece); the Upper Triassic ones are contained in nodular limestones like the Ammonitico Rosso of Hallstatt (Austria), as well as in Halobia cherty limestones of the Pindos basin in Italy, Yugoslavia and Greece. In the Halobia limestones it is possible, in spite of the recrystallization effects, to recognize such an abundance of organic forms — even if in fragments — that we can suppose the original sediment to be a kind of nannoplankton ooze.Because of the very low accumulation rate (few metres/m.y.) of the Middle Triassic Ammonitico Rosso limestones, the coccoliths cannot be considered a significant factor of carbonate pelagic sedimentation at this time; the very high accumulation rate (up to 25 metres/m.y.) of the Upper Triassic cherty limestones in the Pindos basin, on the contrary, allows the nannoplankton to be considered a very important agent of calcareous pelagic sedimentation. The authors hypothesize that the Dogger-Malm, mainly represented by radiolarites, was only a temporary interlude in the Mesozoic pelagic carbonate sedimentation.  相似文献   

17.
Chavarie  L.  Reist  J. D.  Guzzo  M. M.  Harwood  L.  Power  M. 《Hydrobiologia》2019,840(1):157-172
Hydrobiologia - Insights from long-term subsistence fisheries data can improve our understanding of the population-specific responses of Arctic charr, Salvelinus alpinus, to environmental...  相似文献   

18.
19.
海河流域生态功能区划   总被引:6,自引:0,他引:6  
从海河流域自身的特征出发,运用RS、GIS技术,采用定性和定量分析相结合的方法,对海河流域生态功能区进行划分.结果表明:海河流域可划分为5个生态区、24个生态亚区和114个生态功能区;以流域尺度上占主导地位的4项生态功能(水源涵养、水土保持、防风固沙和生物多样性保护)为依据,确定了对海河流域具有重要意义的11个重要生态功能区域.该区划结果明确了对海河流域生态安全具有重要意义的区域,可用于指导海河流域自然资源的有序开发利用和产业的合理布局,为海河流域生态环境保护提供了科学依据,对维护海河流域生态安全具有重要意义.  相似文献   

20.
Habitat fragmentation by damming can affect the persistence of single species population and also coexistence of two or more species through intensified competition. This study examined the effects of habitat fragmentation by damming on the coexistence of two stream-dwelling salmonids: the southern form of white-spotted charr (Salvelinus leucomaenis japonicus) and the red-spotted masu salmon (Oncorhynchus masou ishikawae). We examined charr, salmon, and dam distributions in 27 streams of the Fuji River basin, central Japan. In the 1970s, there were streams with five sympatric and 22 allopatric populations (n = 13 for charr, n = 9 for salmon). However, from the 1970s to 2004, 356 impassable dams were constructed in the surveyed streams, and four of the five sympatric streams became allopatric. In the extant sympatric stream, more than 20 dams fragmented habitat. Species distributions were separated by dams (with decreasing altitude) in the following order: extirpation area, charr-dominant area, and salmon-dominant area. Within the uppermost sympatric section (i.e., situated between the dams), salmon congregated in the largest uppermost pool just below the dam; despite these conditions, salmon frequency increased in the downstream direction at the stream scale. The results suggest that habitat fragmentation threatens the coexistence of stream-dwelling charr and salmon at both the basin and stream scales. We believe that exclusion of one species by another is likely in extremely fragmented habitats with minimal gradients and little variation in physical conditions (through reduced stream gradient and increased sand sedimentation caused by damming). In addition, multiple sites of damming ensure that there are no salmonid refuges from the collapse of metapopulation structure. In such fragmented habitats, even small tributaries serve important roles, as they are used mainly by salmonid fry and juveniles. We propose that habitats of native salmonids should be maximized by reconnecting fragmented habitats as part of a broader management plan.  相似文献   

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