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Ting-Long Guan Bo Zeng Que-Kun Peng Bi-Song Yue Fang-Dong Zou 《Biochemical Systematics and Ecology》2009,37(3):166-173
Forest musk deer (Moschus berezovskii) are rare as a result of poaching for musk and habitat loss. Some captive populations of forest musk deer have been established for decades in China. However, little genetic information is available for conservation management. In this paper, genetic variations, population structures, and the genetic bottleneck hypothesis were examined using 11 microsatellite loci from captive populations in Miyalo, Jinfeng and Maerkang in Sichuan Province, China. Estimates of genetic variability revealed substantial genetic variation in the three populations. A total of 142 different alleles were observed in 121 forest musk deer and the effective number of alleles per locus varied from 6.76 to 12.95. The average values of observed heterozygosity, expected heterozygosity, and Nei's expected heterozygosity were 0.552, 0.899 and 0.894 respectively. The overall significant (P < 0.001) deficit of heterozygotes because of inbreeding within breeds amounted to 34.5%. The mean FST (P < 0.001) showed that approximately 90.2% of the genetic variation was within populations and 9.8% was across populations. The UPGMA diagram, based on Nei's unbiased genetic distance, indicated that the three populations were differentiated into two different groups and it agreed with their origin and history. Bottleneck tests indicated that all three populations have undergone a population bottleneck, suggesting a small effective population size. Acknowledging that the genetic structure of populations has crucial conservation implications, the present genetic information should be taken into account in management plans for the conservation of captive forest musk deer. 相似文献
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McNab BK 《Integrative and comparative biology》2006,46(6):1159-1168
The energy expenditure of endotherms, through its impact onthe rate of reproduction, affects their ability to withstandcompetition, to tolerate environmental disturbances, and toendure predation. The fecundity of eutherian mammals increaseswith rate of metabolism because the post-natal growth rate increasesand the gestation and conception-to-weaning periods decreasewith a mass-independent increase in basal rate of metabolism.These correlations account for the observation that speciesthat have large population fluctuations have high rates of metabolismand reproduction. Species with high rates of metabolism out-competespecies with low rates when using resources that permit consumersto have high rates of metabolism, which explains why eutheriancarnivores replace marsupial carnivores, none of which havehigh basal rates as a result of their form of reproduction.Fecundity in birds also appears to correlate with energy expenditure,which may account for the huge die-off of birds endemic to oceanicislands after the invasion of humans: island endemics, manyof which have low rates of metabolism, are unable to increasefecundity in response to a human-based increase in mortality.The long-term protection for endotherms characterized by lowrates of energy expenditure requires their isolation from highlevels of predation and competition, conditions that are likelyto occur only on islands free from eutherian predators and withlow species diversity. Such endotherms may survive on continentsif they are ecologically isolated from the general fauna. 相似文献
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The extensive use of phenol compounds and the inability to remove these compounds during wastewater treatment have resulted in the widespread occurrence of phenols in the natural environment. Phenols have been linked to serious risks to human and environmental health. Hence, the need to develop technologies that can effectively remove phenols from wastewater and source waters is a pressing challenge. In this study, light ceramic particles were immersed in activated sludge acclimated to degrade phenol, and microorganisms were allowed to attach to the particles surface to form biofilm. Then the ceramic particles with biofilm were moved into the photolytic circulating-bed biofilm reactor made of quartz glass, which was used for the degradation of phenol by three protocols: photolysis with UV light alone (P), biodegradation alone (B), and the two mechanisms operating simultaneously (photobiodegradation, P&B). The experimental results indicated that phenol removal rate was quickest by B experiment. However, P&B experiment gave more complete mineralization of phenol than that by other protocols. During P&B experiment, the microorganisms grown on porous ceramic carrier still kept the bioactivity degrading phenol, even under UV light irradiation. However, the dominant members of the bacterial community changed dramatically after the intimately coupled photobiodegradation, according to molecular biological analysis to the biofilm. Whereas Beijerinckia sp. was the dominant strain in the inoculum, it was replaced by Thauera sp. MZ1T that played a main role on degrading phenol during P&B experiment. 相似文献
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Quantitative analysis of the community structure of tropical amphibian assemblages and its significance to conservation 总被引:1,自引:0,他引:1
Amphibian community structure in five tropical sites was studied using dominance, diversity, evenness indices, niche breadth and overlapping scores and association analysis. Ten species of amphibians with average density/ha varying from 8 to 49 in different sites were collected.Rana limnocharis andBufo melanostictus were respectively the dominant amphibia in paddy fields and other sites. Niche breadth scores indicatedRana limnocharis, Bufo melanostictus andRana cyanophlyctis as habitat generalists indicating wide tolerance to environmental gradients. Five frog speciesi.e. Rana tigerina, Microhyla ornata, Ramanella variegata, Uperedon systoma andPolypedates maculatus were considered habitat specialists indicating narrow tolerance to environmental gradients. Niche breadth scores were found to be a function of the cumulative relative abundance value of different species. The niches ofRana limnocharis andRana cyanophlyctis, Bufo melanostictus andBufo stomaticus showed maximum overlapping.Rana tigerina showed maximum niche overlapping withRana variegata in paddy fields and withMicrohyla ornata when all sites were taken together. The coefficient of community index was maximum between the paddy fields and minimum between the paddy fields and forest site.Rana tigerina occurred very sparsely and analysis of data indicates that its population are threatened and require conservation measure. 相似文献
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A study of phenological patterns in macromycete communities in Veracruz, Mexico was carried out in order to understand changes in community structure across regions of different vegetation types. Previous studies suggest that similarities in community composition occur when there are similarities in certain geographical and climatological characteristics, however they do not address functional groups or seasonal changes across regions. Macromycete communities in Veracruz showed similar species distribution patterns, but individual assemblages changed structure seasonally, changes that were strongly correlated with rainfall. Interestingly, the number of functional groups (species performing similar ecological functions) was not determined by rainfall, but the distribution of species within functional groups was determined by rainfall. Temperature did not appear to play a role in structuring community diversity at this regional scale. However, temperature and other environmental factors such as pH or light may be the mechanism triggering phenological patterns, and influencing the species pool at localized scales. This work brings new light to fungal community diversity patterns in a largely unknown group of species. 相似文献
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We compare results of parallel ground and canopy netting of bats (Microchiroptera) in three adjacent forest sites near Belém, Brazil, to document possible differences in vertical distribution of species. We caught 1871 individuals representing 49 species of three families (Emballonuridae, Phyllostomidae, Vespertilionidae). Capture effort, totaling 1955.5 mistnet hours in several cycles over a two-year period, was similar for ground and canopy nets. The canopy rigs yielded more species (n = 41) than the ground nets (n = 35), but both samples were characterized by rank abundance curves with similar shape and with a dominance of frugivores (Phyllostomidae). Nearly half (n = 24) of the species were captured in numbers too small (n < 6) to allow firm classification, but differences in capture frequencies of some of the better-sampled species in high and low nets reveal vertical stratification. Species-specific differences in diet, foraging strategies, roost sites, and sampling bias contribute to this pattern. As a result of the differential use of space among bats, alterations of forest structure are likely to result in changes in structure and function of local bat communities, but our limited knowledge of natural history and ecology of many species limits definition of changes. We see a critical need for further research into the extent to which habitat complexity influences species richness and abundance of bats. This information is especially important in view of the need to develop and apply conservation-oriented programs to maintain biodiversity. A review of recent improvements in techniques for inventorying bats shows that a combination of methods, including mistnetting and acoustic monitoring, is mandatory for such studies. 相似文献
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神农架地区珍稀植物沿河岸带的分布格局及其保护意义 总被引:9,自引:1,他引:9
在神农架香溪河流域从源头到河口的不同海拔高度沿河岸带共设置 4 0个与河流方向平行的10 0m× 10m的样带 ,进行了植物群落学调查研究 .结果表明 ,沿河岸带分布有珍稀植物 14种 ,占神农架地区珍稀植物总数的 4 2 .4 % .这些珍稀物种主要分布在海拔 12 0 0~ 180 0m山地常绿阔叶落叶阔叶混交林带 ,珍稀植物种类的物种丰富度在中等海拔高度上最大 .珍稀植物的种类可划分为低海拔、中等海拔和高海拔 3组 .针对珍稀植物的分布特点 ,明确指出应重视河岸带在生物多样性、尤其是珍稀物种保护方面的重要作用 . 相似文献
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Yan Zhou Yundong Cao Houqiang Chen Yu Long Fengming Yan Chongren Xu Rongjiang Wang 《Journal of Insect Conservation》2012,16(2):207-214
In 2004 and 2005, we investigated the distribution of the Glanville fritillary butterfly (Melitaea cinxia) and its host plant in the Tianshan Mountains of China, in order to clarify its habitat utilization. Female butterflies were
almost captured on dry meadows on slopes, where plenty of host plant (Veronica spicata) is distributed. Although there are host plants on meadows at higher altitude (>2,050 m), no butterfly was found there. Among
the meadows with host plants, a patch of dry meadow (newly-found meadow) was considered as a natal site because of the high
density and freshness of butterflies. Unlike females, male butterflies were almost captured in valleys, where there are no
host plants and fewer nectar plants. It might be related to specific mating system of M. cinxia in the study site, or specific environmental factors. Thus valleys are important habitat for males. Although the status of
M. cinxia is yet unknown in China, we give some suggestions for conservation based on this study. First, dry meadows with host plants
are the essential component for persistence of M. cinxia, among which the specific sites with more favourable conditions, such as natal site, are most important. Second, as a site
with adult resource requirement, valleys should be included as part of the habitat of the butterfly. Finally, meadows at higher
altitude are not utilized at present but they are potential habitats which need to be maintained for any shifts in altitudinal
range in response to global warming in the future. Hence, the trade-off of present cost and future benefit should be taken
into account when formulating a conservation strategy for M. cinxia in the Tianshan Mountains of China. 相似文献
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C.‐C. Chen K.J.‐C. Pei C.‐M. Yang M.‐D. Kuo S.‐T. Wong S.‐C. Kuo F.‐G. Lin 《Journal of medical primatology》2011,40(1):2-5
Background Natural infection of hantavirus in orangutans has never been reported. Methods Enzyme‐linked immunosorbent assays (ELISA), Indirect immunofluorescence assay (IFA), and RT‐PCR were used to diagnosis a suspected case in a pet orangutan in southern Taiwan. Results Although the RT‐PCR result was negative, the high IgG titer in the beginning and its dramatic drop after treatments suggested a recent Seoul‐type hantavirus infection. Conclusions Hantavirus transmission and its potential damage to wild orangutans should not be overlooked. 相似文献
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The goal of this research was to investigate genetic variation in Isoëtes malinverniana (Isoëtaceae) to select candidate populations for future conservation efforts. To this aim, ISSR and AFLP analyses, carried out using six and four primer combinations, respectively, produced a total of 425 bands, 97.18% of which were polymorphic.Our results suggest that I. malinverniana shows medium to high genetic diversity (mean Nei's genetic diversity: H = 0.1491 for ISSR data; H = 0.2289 for AFLP data) and a substantial amount of gene flow between the analysed populations (Nm = 1.768, with combined ISSR and AFLP data). The moderate levels of population differentiation support the hypothesis that the fragmentation and isolation of I. malinverniana occurred only recently, probably due to the intensive agriculture practice and water pollution.These results will be used to focus further studies aimed at supporting reintroduction programs within suitable sites of the distribution area. 相似文献
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枸杞岛潮下带沙地生境鱼类群落结构和季节变化 总被引:11,自引:0,他引:11
为了解岛礁水域沙地生境的鱼类群落结构特征,评估该生境对鱼类资源养护的潜在作用,于2009年采用多网目组合刺网对枸杞岛潮下带沙质区域进行了逐月采样,同步设置岩礁为对照生境.应用α和β多样性指数结合相对重要性指数、相对渔获率、ABC曲线和聚类排序方法对两种生境中的鱼类组成、多样性变化和群落格局与变化进行了全面探讨.全年在沙地和岩礁生境共采集鱼类63种,隶属11目38科56属,2种生境各自出现的鱼类皆为46种.受暖水种频繁出现在沙地生境的影响,潮下带沙质区域鱼类区系比岩礁生境略显丰富,且春夏季的渔获量普遍高于岩礁生境;由于种类组成均匀度较低,沙地生境各季节的α多样性普遍较低,夏季显著低于岩礁生境.日本须鳎是沙地生境的指示种,为早春、夏末和秋冬季沙地底层优势鱼种.5-7月鳀、多数月份鲻和10月份鳗鲇等种类对沙地生境的阶段性利用,使其形成了区别于以趋礁性鱼类为优势类群的岩礁生境的群落格局和季节动态.沙地是多种鱼类幼鱼阶段的庇护所和饵料场,是鲆鲽类的良好栖息地.沙地生境在维持鱼类区系和养护鱼类资源方面具有重要作用. 相似文献
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Seasonal change in the opportunity for sexual selection 总被引:1,自引:0,他引:1
Environmental and population parameters that influence the strength of sexual selection may vary considerably over the course of the reproductive season. However, the potential for sexual selection frequently fails to translate into variation in reproductive success among individuals. We investigated seasonal changes in variation in reproductive success, measured as the opportunity for sexual selection, using parentage analysis in 20 experimental populations of the European bitterling (Rhodeus amarus, Cyprinidae), a small freshwater fish with a promiscuous, resource-based mating system. We showed that although the largest males sired most offspring over the entire reproductive season, variation in reproductive success and hence the opportunity for sexual selection was low at the start of the season but increased significantly at its end. This seasonal difference probably arose from the superior competitive endurance of large males and from a higher temporal clustering of reproductively active females at the start of the breeding season than later in the season. The spatial distribution of oviposition sites had a negligible effect on the variation in reproductive success. We discuss the potential implications of our results for the importance and strength of sexual selection in natural populations. 相似文献
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广州市昆虫群落结构及动态 总被引:1,自引:0,他引:1
2005-2006年对广州市全区域的昆虫群落进行6次调查,对该区域昆虫群落结构、多样性及时间动态进行了分析.共记述22个目、216个科.鞘翅目的类群最丰富,双翅目、鳞翅目、膜翅目和半翅目次之;鞘翅目昆虫的个体数量最多(30.45),其次为鳞翅目(18.89)和膜翅目(14.78).6~7月昆虫类群数和个体数量最多,12月最少;6~7月的种类丰度最高,其次为3~4月、9~10月,12月最低;Shannon-Wiener指数从高到低依次为6~7月、9~10月、3~4月、12月;Pielou均匀度指数从高到低依次为6~7月、9~10月、12月、3~4月;12月的种类优势度最高,其次为3~4月、9~10月,最低为6~7月. 相似文献
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Jing Wang Naoya Tochio Aya Takeuchi Jun-ichi Uewaki Naohiro Kobayashi Shin-ichi Tate 《Biochemical and biophysical research communications》2013
HMGB1 (high-mobility group B1) is a ubiquitously expressed bifunctional protein that acts as a nuclear protein in cells and also as an inflammatory mediator in the extracellular space. HMGB1 changes its functions according to the redox states in both intra- and extra-cellular environments. Two cysteines, Cys23 and Cys45, in the A-domain of HMGB1 form a disulfide bond under oxidative conditions. The A-domain with the disulfide bond shows reduced affinity to cisplatin modified DNA. We have solved the oxidized A-domain structure by NMR. In the structure, Phe38 has a flipped ring orientation from that found in the reduced form; the phenyl ring in the reduced form intercalates into the platinated lesion in DNA. The phenyl ring orientation in the oxidized form is stabilized through intramolecular hydrophobic contacts. The reorientation of the Phe38 ring by the disulfide bond in the A-domain may explain the reduced HMGB1 binding affinity towards cisplatinated DNA. 相似文献
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Seasonal influences on fungal community structure in unimproved and improved upland grassland soils 总被引:1,自引:0,他引:1
Seasonal and management influences on the fungal community structure of two upland grassland soils were investigated. An upland site containing both unimproved floristically diverse (U4a) and improved mesotrophic (MG7b) grassland types was selected. Samples from both grassland types were taken at five times in one year. Soil fungal community structure was assessed using fungal automated ribosomal intergenic spacer analysis (ARISA), a DNA-profiling approach. A grassland management regime was found to strongly affect fungal community structure, with fungal ARISA profiles from unimproved and improved grassland soils differing significantly. The number of fungal ribotypes found was higher in unimproved than improved grassland soils, providing evidence that improvement may reduce the suitability of upland soil as a habitat for specific groups of fungi. Seasonal influences on fungal community structure were also noted, with samples taken in autumn (October) more correlated with change in ribotype profiles than samples from other seasons. However, seasonal variation did not obscure the measurement of differences in the fungal community structure that were due to agricultural improvement, with canonical correspondence analysis indicating grassland type had a stronger influence on fungal profiles than did season. 相似文献