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1.
Eight polymorphic loci were surveyed in three samples of the gastropodTegula rustica collected in a clean area of Peter the Great Bay and in three samples from a heavily polluted area of the bay. Macrospatial,
microspatial, and temporal differences in allele frequencies and heterozygosity were found at some of the loci; however, the
genetic similarity among the samples was very high. It is concluded that allozyme variability at the surveyed loci ofT. rustica cannot be used in pollution monitoring of Peter the Great Bay. 相似文献
2.
Allozyme variability was assessed, using starch gel electrophoresis, at 15 polymorphic loci in two samples of the Pacific mussel Mytilus trossulus collected from local populations in heavily (Golden Horn Bay) and slightly polluted areas (Sukhoputnaya Bay) of Peter the Great Bay. Significant differences between samples were found in the genotypic frequencies at nine loci and in allele frequencies, at six loci. The results are suggestive of the differential survival of individuals having different genotypes and alleles at some of the surveyed loci under conditions of pollution. Our data are not in conflict with the hypothesis of the adaptive significance of allozyme polymorphism. 相似文献
3.
S. D. Kashenko 《Russian Journal of Marine Biology》2000,26(5):338-341
Our studies show that seawater from different sites in Nakhodka Bay has a deleterious effect on the development of the sea
urchinStrongylocentrotus intermedius. As development proceeded to the pluteus I stage, the percentage of abnormal larvae maintained in water from Nakhodka, Novitskogo,
and Vrangelya Bights increased markedly (66.7±2.2, 67.1±2.6, and 54.6±1.8%, respectively). These larvae developed more slowly,
were smaller, and differed from those in the control in the intensity of color of their echinochrome granules. In water from
Nakhodka and Novitskogo bights, larval survival rates were lower than in the control. This suggests that the water of Nakhodka
Bay is heavily polluted, especially in its harbor areas. 相似文献
4.
Allozyme variability was studied in 11 polymorphic loci in three samples of the sea urchin Strongylocentrotus droebachiensis using the method of gel electrophoresis. One sample was taken from a population of normal environmental conditions (Avacha Bay, Kamchatka Peninsula), the other two were sampled in Kraternaya Bay (Yankicha Island, the Kuriles): the first sample was from a bottom site where the animals were subjected to continuous stress resulting from the products of volcanic hydrothermal vents and the second sample was from a bottom site where that stress effect was periodical. Statistically significant differences in the genotypic allele frequencies and in levels of heterozygosity of some loci were revealed between the Avacha Bay and Kraternaya Bay samples. Moreover, similar differences, but in other loci, were revealed for the Kraternaya Bay samples. The possible causes of these distinctions are discussed. A conclusion on the primary role of natural selection in the origin of the observed distinctions and on the conformity of the observed data to the hypothesis of selective significance of a part of the allozyme polymorphism is put forth. 相似文献
5.
S. M. Nikiforov 《Russian Journal of Marine Biology》2000,26(2):103-108
Allozyme variability was investigated at 18 polymorphic loci in 9 samples of the bivalveMytilus trossulus (Gould, 1850) from Vostok Bay, Sea of Japan. Significant differences in allele frequencies at some loci were found between
samples from different age cohorts and different depths. Genetic distances between samples were as great as (and often exceeded)
those typically found between geographically separate populations in Peter the Great Bay. Some practical recommendations for
experimental researchers are proposed. 相似文献
6.
Allozyme variability in 16 polymorphic loci in two size cohorts of large (30.0 ± 6.3 mm) and small (9.8 ± 2.3 mm) spat of the mussel Mytilus trossulus (Gould) coinhabiting the intertidal zone in Brazhnikov Bay (Amursky Bay, Sea of Japan) was studied 1988–1989. It was determined that the size cohorts compared were highly similar genetically; Nei's minimum distances were 0.014 and 0.016 in 1988 and in 1989. However, statistically significant differences in allele frequencies were found at 2 loci, both in 1988 and in 1989. The loci differing by allele frequencies in 1988 did not coincide with those in 1989. Significant differences by heterozygosity between the cohorts were found only at the Idg-1 and Est-3 loci, 1988; and at the Aat-1, 6-Fgd, Est-3 loci, 1989; but the average heterozygosity was not significantly different in the cohorts for both years. A deficiency of heterozygotes (Dg) was observed almost at all loci in both cohorts. The mean Dg values were significantly higher in the cohort of small size individuals. Since the environmental conditions for both cohorts were similar, the allozyme differences between them were not a result of natural selection. A possible cause of the allozyme and size differences among the mussel cohorts is the gap in the settling time of larvae, which entails the formation of two size cohorts of mussels. Such a gap was caused by protraction of spawning period of M. trossulus and by the formation of segregate larval pools from various mussel populations differing in allele frequencies. 相似文献
7.
The generic composition of the heterotrophic bacterial population of Tokyo Bay, which is now highly polluted and eutrophic, was compared with that of the adjacent, less polluted regions of Sagami Bay and Suruga Bay. Members of Vibrionaceae predominated in the bacterial flora of seawater and zooplankton samples from Sagami Bay, Suruga Bay, and the mouth of Tokyo Bay. However,Vibrio spp. formed only a small proportion of the bacterial population of the water and sediment samples from the inner Tokyo Bay; there the Gram-negative, nonmotile, nonpigmented bacteria, which were tentatively identified asAcinetobacter, were predominant. The result of experiments, in which seawater samples from Tokyo Bay were incubated under various experimental conditions, indicated that two significant factors apparently control the growth ofVibrio spp. in seawater; (1) a direct antagonism betweenVibrios and phytoplankton undergoing rapid growth, and (2) a limiting organic nutrient forvibrios. 相似文献
8.
以苯并(a)芘(50 mg/L)为唯一碳源,对新疆芦草沟煤矿开采区土壤微生物进行3代胁迫培养(每代60 d);采用PCR-DGGE方法了解不同污染程度土样中降解苯并(a)芘的微生物类群和多样性特点;利用高效液相色谱(HPLC)测定胁迫培养每代培养物混合菌群对苯并(a)芘的降解能力。PCR-DGGE结果显示:不同污染程度原始样品与苯并(a)芘胁迫培养第3代培养物的微生物香浓指数(H)、丰度(S)和均匀度(E)有所不同,其中重度污染培养物降解苯并(a)芘的微生物类群最丰富。对优势条带进行克隆,其主要归属于变形菌门(Proteobacteria)、拟杆菌门(Bacteroidetes)和放线菌门(Actinobacteria)。经HPLC检测发现重度污染样品中的群体微生物对苯并(a)芘的降解率明显高于轻度和中度污染样品,达到78.4%。研究表明新疆芦草沟煤矿开采区污染的土壤中可能蕴藏着降解苯并(a)芘的微生物资源。 相似文献
9.
Kathryn J. Coyne Clinton E. Hare Linda C. Popels David A. Hutchins S. Craig Cary 《Harmful algae》2006,5(4):363
The toxic dinoflagellate, Pfiesteria piscicida, is a common constituent of the phytoplankton community in the Delaware Inland Bays, USA. In this study, molecular methods were used to investigate the distributions of benthic stages (cysts) of P. piscicida in sediment cores from the Delaware Inland Bays. Cores from 35 sites were partitioned into nephloid and anoxic layers and analyzed for P. piscicida by nested amplification of the 18S rDNA gene using P. piscicida-specific primers. The presence of inhibitory substances in the PCR reaction was evaluated by inclusion of an exogenous control DNA in the extraction buffer, thus eliminating samples that may yield false-negative results. Our results indicate a patchy distribution of P. piscicida in sediments of the Delaware Inland Bays, with distinct differences between each of the three bays. Overall, P. piscicida was found more frequently in sediments from Rehoboth Bay compared to Indian River and Little Assawoman Bays. These differences suggest (i) that populations of P. piscicida may be more widely distributed in Rehoboth Bay, (ii) that populations of P. piscicida may have been introduced to Rehoboth Bay at an earlier time, (iii) that past blooms of P. piscicida in Rehoboth Bay estuaries may have seeded the sediments with higher numbers of cysts, and/or (iv) that Rehoboth Bay sediments may be more resistant to clearing due to storm turbulence. 相似文献
10.
Five sympatric colour varieties of the hoplonemertean Tetrastemma nigrifrons (var. pallidum, var. bicolor, var. purpureum, var. punctata, var. albino) were found in Vostok Bay (the Sea of Japan). The taxonomic status of the varieties, some of which have been known for almost a century, was uncertain. Starch gel electrophoresis was used to compare allele frequencies of these varieties at 19 isozyme loci. Neither fixed allelic differences nor statistically significant differences in allele frequencies between different colour varieties was revealed. It was concluded therefore that all the colour varieties studied are conspecific. As estimated from the electrophoretic screening of 24 isozyme loci, the species is highly variable at the molecular level. It has high mean values of observed and expected heterozygosity estimates, H
o =0.313 ± 0.049 and H
e =0.323 ± 0.050, and is one of the most variable species among invertebrates. 相似文献
11.
Genetic variability and interpopulational differentiation of Artemia strains from South America 总被引:2,自引:2,他引:0
Seven Artemia samples from three South American countries (Chile, Brazil, Peru) were studied by starch electrophoresis with the aim of comparing levels of genetic variation and genetic similarity to representative populations of A. franciscana (San Francisco Bay, California, USA) and A. persimilis (Buenos Aires, Argentina), which are species endemic to the New World. Based on the analysis of 22 loci, parameters measuring genetic variability were, for some populations, found to be among the highest reported for Artemia so far. The percentage of polymorphic loci varied from 31.8% (Piura, Peru; Buenos Aires) to 50% (Los Vilos and Salar de Atacama, Chile), while the observed heterozygosity varied from 0.025 (Piura) to 0.165 (Los Vilos, Chile). A dendrogram based on Nei's genetic distance (D) produced four major groups. The Argentinian form, A. persimilis; the San Francisco Bay strain together with samples from Brazil (Macau and Rio Grande do Norte) and Chile (Pichilemu and Salar de Atacama); two coastal populations from Chile (Los Vilos and Iquique) and the sample from Peru (Piura). These four groups have inter-group D values that are, in some cases, far above those normally associated with conspecific populations. 相似文献
12.
The allozyme variability for 15 loci in two samples of the Pacific mussel Mytilus trossulus collected from a single giant cluster was investigated using the method of gel electrophoresis. One sample was subjected to short-term anaerobic stress and then to a longer aerobic stress, leading to the death of about 85% of the individuals. At some of the loci, significant differences in the genotypic and allele frequencies were found between the samples. The results are suggestive of the differential survival of mussels with different genotypes and alleles at some of the surveyed loci under stress. Our data are in agreement with the hypothesis of the adaptive significance of allozyme polymorphism. 相似文献
13.
越冬和复苏时期太湖水体蓝藻群落结构的时空变化 总被引:1,自引:0,他引:1
为研究太湖蓝藻在越冬与复苏时期群落结构的时空变化规律,于2008年11月,2009年2月,2009年4月,在太湖富营养化较严重的湖区选取8个采样点 (梅梁湾、竺山湾、贡湖湾、大浦、西太湖、南太湖、湖心和湖湾交汇处),分3层采水样,过滤并提取样品DNA经PCR扩增蓝藻16S rDNA序列,采用T-RFLP(末端标记的限制性酶切片段长度多样性)技术分析蓝藻群落结构和多样性变化。共得到87个不同的T-RFs(末端限制性酶切片段),表明太湖蓝藻具有丰富的基因多样性。T-RF相对丰度和聚类分析结果表明,太湖蓝藻群落结构在垂直空间上相似性较高,相似度 > 50%;在水平空间,与Microcystis spp.对应的信号峰在8个采样点均为最强峰(相对丰度为17.7% 47.5%)。竺山湾蓝藻多样性最低,西太湖最高,但其余采样点间蓝藻群落和Shannon多样性指数没有显著差异(P>0.05)。Microcystis相对丰度与Shannon多样性指数呈显著负相关(皮尔逊相关系数为-0.958)。在时间尺度上,相似性分析(Analysis of similarity,ANOSIM)结果显示太湖蓝藻群落结构存在极显著差异( P<0.01) 。春季复苏时蓝藻多样性最高,秋季衰亡时最低。聚类分析表明样品聚成两大特征类群,秋季衰亡时样品独自聚为1支,而春季复苏期和冬季越冬期样品彼此混杂。 相似文献
14.
We studied host-plant preference and performance of the leaf beetle, Melasoma lapponica, around Severonikel smelter situated in Monchegorsk, Russia. The breadth of feeding niche (Smith's measure) based on both field counts and preference tests decreased with an increase of ambient SO2 concentration, but showed no relationship with either metal pollutants or beetle population densities. In heavily polluted plots (mean annual SO2 concentrations 400–1000 g/m3) the beetles concentrated on Salix borealis, Whereas in moderately and slightly polluted plots they used other willow species as well. No difference in survival was revealed between M. lapponica fed with leaves of S. borealis from heavily and sloghtly polluted plots. However, performance of larvae fed with Salix caprea and S. Phylicifolia was significantly lower when leaves were collected from heavily polluted plots. In these plots beetles clearly preferred S. borealis, the only species assuring high survival of M. lapponica under strong pollution impact. Decrease in preference of two less favourable hosts, S. caprea and S. phylicifolia, with increase in pollution can therefore be considered as an adaptive response of M. lapponica to pollution-induced changes in host-plant quality. 相似文献
15.
A. G. Byankin 《Russian Journal of Marine Biology》2001,27(5):333-335
This paper describes tumorlike formations in the olfactory organ of the striped mullet Mugil cephalusinhabiting polluted waters of Zapadnaya Bay (Sovetskaya Gavan' Bay, western coast of Tatar Strait). The structure of these tumorlike formations is characteristic of fibroma. The appearance of the tumors is apparently associated with carcinogenic industrial wastes and radioactive contamination of the bay. 相似文献
16.
【目的】揭示胶州湾典型污染海域半知菌群体结构多样性动态变化与生境的关系。【方法】根据以往对近岸污染调查记录,分别确定胶州湾海泊河、李村河入海口为中度、重度污染采样站位,石老人潮间为轻度污染对照站位,利用PCR-DGGE指纹图谱方法,研究该生境半知菌群体结构多样性季节动态变化与污染的关系。【结果】结果证明,污染指标除总氮含量外,其他各项指标含量在三站位的变化趋势为石老人潮间带最低,海泊河居中,李村河含量最高;与石老人站位相比,海泊河、李村河站位污染指标在四季变化较显著。首次证明在重金属和氮磷严重超标的海域,仍存在数量和种类较多的半知菌。PCR-DGGE指纹图谱结果显示,同一站位相似污染程度采样点之间DGGE指纹图谱比较一致,不同站位、不同季节之间指纹图谱存在明显的差异。优势条带割胶测序分析显示,3个站位存在大量的不可培养真菌,青霉属为半知菌优势种,重度污染的李村河入海口除半知菌外,存在较大量的阿米巴虫、腐霉等动物病原菌。【结论】污染海域的半知菌群体结构与生境污染程度及季节具有较密切的联系。 相似文献
17.
Franklin D. Carrasco Victor A. Gallardo Sonia Medrano 《International Review of Hydrobiology》1988,73(4):441-455
The benthic assemblages in two Central Chile nearby embayments were studied from quantitative samples collected from 15 sites at depths of 8–65 m. The macrobenthic infauna (<0.5 mm) of both bays was greatly dominated by polychaetes. Some 93 taxa were identified, of which 51 were polychaetes. The average macrofaunal abundance for all stations (15,021 ind. m−2) is very close to the values reported for the neighboring areas. Numerical classification and ordination (DCA) of sites resulted in three site-groups mostly reflecting differences in the bottom sediments: the muddy-bottom stations of Concepción Bay and the shelf-associated stations, the sandy-bottom stations of San Vicente Bay and an heavily polluted station at San Vicente port. Classification of species showed that the muddy-bottom stations and the sandy-bottom sites had characteristic species assemblages. The macrofaunal assemblages presented high dominance values, which were due to the high numerical abundances of a few species in the collections. 相似文献
18.
Jamet Jean-Louis Bogé Gérard Richard Simone Geneys Claude Jamet Dominique 《Hydrobiologia》2001,457(1-3):155-165
The abundance and the diversity of the zooplankton community were studied during an annual cycle in three shallow bays differently affected by anthropogenic inputs of Toulon area in the northwest Mediterranean Sea (France). Environmental variables of water quality were also considered. Our results discriminated Little Bay from the La Garonne and Niel Bay. Little Bay, heavely perturbed by anthropogenic inputs, had high chlorophyll a levels, abundant zooplankton, a low diversity index, a high dominance Index and a single dominant species (Oithona nana). La Garonne Bay and Niel Bay, much less polluted, had low chlorophyll a levels, low zooplankton abundance, low dominance Index and high diversity index and eveness. In addition, O. nana occurred rarely in the latter bays. Zooplankton successions were also different between Little Bay and the two other bays. 相似文献
19.
Electrophoretic variation within and between North Atlantic minke whale samples(Balaenoptera acutorostrata) from West Greenland, Iceland, and Norway was investigated. In the West Greenland samples, 28 enzyme systems were examined,
representing 36 loci, of which 6 were found to be polymorphic. In Icelandic and Norwegian samples, 22 enzyme systems were
examined, representing 29 loci, of which 6 and 5 were found to be polymorphic, respectively. The average heterozygosity was
0.058 (SE=0.024) in samples from West Greenland, 0.074 (SE=0.028) in samples from Iceland, and 0.054 (SE=0.023) in samples
from Norway. No significant deviations from the expected Hardy—Weinberg genotypic frequencies, within samples taken from the
same area, were found. Significant differences in allele frequencies were observed, however, between samples from the three
different areas. The average Nei's genetic distance was 0.014 and the averageF
st value was 0.126. The genetic differences between the samples from the different areas indicate that those from West Greenland,
Iceland, and Norway represented different breeding populations. 相似文献
20.
The intentional introduction of red king crab, Paralithodes camtschatica (Tilesius, 1815) in the Barents Sea represent one of a few successful cases and one that now supports a commercial fishery.
Introductions of alien species into new environments are often associated with genetic bottlenecks, which cause a reduction
in the genetic variation, and this could be important for the spreading potential of the species in the Atlantic Ocean. Red
king crab samples collected in the Varangerfjord located on the Barents Sea (northern Norway) were compared with reference
crab samples collected from the Bering Sea and Kamchatka regions in the Pacific Ocean. All samples were screened for eleven
microsatellite loci, based on the development of species-specific primers. The observed number of alleles per locus was similar,
and no reduction in genetic variation, including gene diversity and allelic richness, was detected between the Varangerfjord
sample and the reference sample from Okhotsk Sea near Kamchatka, indicating no genetic bottlenecking at least for the microsatellite
loci investigated. The same results were found in comparison with the sample from Bering Sea. The level of genetic differentiation
among the samples, measured as overall F
ST
across all loci, was relatively low (0.0238) with a range of 0.0035–0.1000 for the various loci investigated. The largest
pairwise F
ST
values were found between the Bering Sea and Varangerfjord/Barents Sea samples, with a value of 0.0194 across all loci tested.
The lowest value (0.0101) was found between the Varangerfjord and Kamchatka samples. Genetic differentiation based on exact
tests on allele frequencies revealed highly significant differences between all pairwise comparisons. The high level of genetic
variation found in the Varangerfjord/Barents Sea sample could be of significance with respect to further spreading of the
species to other regions in the North Atlantic Ocean. 相似文献