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Validity and Systematic Position of Rana altaica(Rana:Ranidae):Results of a Phylogenetic Analysis 被引量:6
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作者 杨军校 周炜帏 +3 位作者 饶定齐 POYARKOV A.Nikolay KUZMIN Sergius L 车静 《Zoological Research》 CAS CSCD 北大核心 2010年第4期353-360,共8页
In order to evaluate the phylogenetic position and validity of Rana altaica,we investigated the phylogeny of brown frogs in Eurasia by Bayesian Inference and Maximum Parsimony analyses of a fragment from the mitochond... In order to evaluate the phylogenetic position and validity of Rana altaica,we investigated the phylogeny of brown frogs in Eurasia by Bayesian Inference and Maximum Parsimony analyses of a fragment from the mitochondrial DNA gene Cytochrome b.Both analyses resolved R.altaica as nesting deeply within R.arvalis.Most samples of the nominal R.altaica from the Altai region and specimens from Central Siberia shared a haplotype with R.arvalis based on the network analysis.The matrilineal relationships suggested that R.altaica should be considered as a junior synonym of R.arvalis.Furthermore,our study suggested that the species group division of Chinese brown frogs should be re-evaluated within a phylogenetic context. 展开更多
关键词 Rana altaica Rana arvalis Rana arvalis altaica Cytochrome b Demographic expansion
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A New β-Carboline Alkaloid and a New Derivate of Isoferulic Acid from Anemone altaica 被引量:2
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作者 Zhong Jie ZOU Yue Sheng DONG Jun Shan YANG 《Chinese Chemical Letters》 SCIE CAS CSCD 2005年第11期1484-1486,共3页
A new β-carboline alkaloid, 4-(9H-β-carbolin-1-yl)-4-oxobutyric acid and a new derivate of isoferulic acid, (E)-3-(3-hydroxy-4-methoxyphenyl)acrylic acid carboxymethyl ester, were isolated from the roots of An... A new β-carboline alkaloid, 4-(9H-β-carbolin-1-yl)-4-oxobutyric acid and a new derivate of isoferulic acid, (E)-3-(3-hydroxy-4-methoxyphenyl)acrylic acid carboxymethyl ester, were isolated from the roots of Anemone altaica. Their structures were determined on the basis of spectral data. 展开更多
关键词 Anemone altaica β-carboline alkaloid isoferulic acid derivate.
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东北虎(Panthera tigris altaica)个体识别技术研究进展 被引量:11
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作者 顾佳音 刘辉 姜广顺 《野生动物》 2013年第4期229-237,248,共10页
对东北虎种群的科学监测是采取有效保护、管理及恢复措施的基础,而准确的个体识别又是保证有效监测的前提。尤其是在中国,在野生东北虎种群数量很少,种群密度极低的情况下,能根据它留下的各种信息进行个体识别就显得尤为重要。目前,用... 对东北虎种群的科学监测是采取有效保护、管理及恢复措施的基础,而准确的个体识别又是保证有效监测的前提。尤其是在中国,在野生东北虎种群数量很少,种群密度极低的情况下,能根据它留下的各种信息进行个体识别就显得尤为重要。目前,用于野生东北虎个体识别的技术主要有:足迹识别、DNA识别、条纹识别以及气味识别等。本文对这几种技术的特点、研究进展、应用注意事项等做了介绍,并且结合中国的实际情况,分析每种技术在中国的适用性,认为如果要建立中国的东北虎种群数量数据库,足迹识别和DNA识别比较适合在中国现有东北虎分布区推广使用。通过足迹识别,信息容易获取,也是最经济和比较成熟的方法;由于种群密度低,含DNA的遗传样本虽不能每次都采集到,但可以长期积累;现阶段条纹和气味识别只能起到辅助的作用。 展开更多
关键词 东北虎 个体识别 种群监测 足迹 DNA 条纹 气味
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Rapid discovery of two unprecedented meroterpenoids from Daphne altaica Pall.using molecular networking integrated with MolNetEnhancer and Network Annotation Propagation
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作者 Wei-Yu Zhou Zi-Han Xi +7 位作者 Ning-Ning Du Li Ye Ming-Hao Jiang Jin-Le Hao Bin Lin Guo-Dong Yao Xiao-Xiao Huang Shao-Jiang Song 《Chinese Chemical Letters》 SCIE CAS CSCD 2024年第8期294-298,共5页
Under the guidance of the approach which integrates molecular networking,MolNetEnhancer and Net-work Annotation Propagation(NAP),daphnaltaicanoids A and B(1 and 2)with unprecedented 9-oxa-tetracyclo[6.6.1.0^(2,6).0^(8... Under the guidance of the approach which integrates molecular networking,MolNetEnhancer and Net-work Annotation Propagation(NAP),daphnaltaicanoids A and B(1 and 2)with unprecedented 9-oxa-tetracyclo[6.6.1.0^(2,6).0^(8,13)]pentadecane and tetracyclo[5.3.0.1^(2,5).2^(4,11)]tridecane central frameworks were iso-lated from Daphne altaica Pall.,representing two types of unparalleled meroterpenoid cores.Their struc-tures were elucidated by extensive spectroscopic analysis,nuclear magnetic resonance(NMR)calcula-tions,DP4+analysis and electronic circular dichroism(ECD)calculations.The plausible biosynthetic path-ways for 1 and 2 were postulated.Biologically,2 exerted potent neuroprotective activities which were su-perior to trolox at 12.5 and 25μmol/L.Moreover,1 and 2 exhibited more noticeable acetylcholinesterase inhibitory activities than donepezil.Molecular docking simulations were performed to explore the inter-molecular interaction of compounds 1 and 2 with acetylcholinesterase.The bioactivity evaluation results highlight the prospects of 1 and 2 as a novel category of neurological agents. 展开更多
关键词 Daphne altaica Pall. Molecular networking MolNetEnhancer NAP Unprecedented meroterpenoid frameworks Neuroprotective activities Acetylcholinesterase inhibitors
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我国圈养和野生东北虎种群线粒体基因组遗传多样性的比较研究
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作者 褚佳宁 徐海涛 +9 位作者 何志健 杨金城 周永恒 刘博洋 崔靓玉 高雨薇 刘丹 徐艳春 姜广顺 杨淑慧 《野生动物学报》 北大核心 2024年第2期231-241,共11页
东北虎(Panthera tigris altaica)是体型最大的猫科(Felidae)动物之一,是极具代表性的珍稀野生动物。现有研究表明,我国野生东北虎种群遗传多样性较低、近交水平较高。尽管目前我国野生东北虎的数量在逐步增长,但通过人工干预来提高野... 东北虎(Panthera tigris altaica)是体型最大的猫科(Felidae)动物之一,是极具代表性的珍稀野生动物。现有研究表明,我国野生东北虎种群遗传多样性较低、近交水平较高。尽管目前我国野生东北虎的数量在逐步增长,但通过人工干预来提高野生东北虎的遗传多样性会更利于其数量的恢复,通过野化放归进行遗传拯救是一种关键策略,但实施遗传拯救之前,必须确定圈养个体与现存野生个体间的遗传关系。采用粪便DNA的高通量测序数据组装了51只横道河子圈养东北虎和13只完达山、老爷岭等地的野生东北虎的线粒体基因组,分析两者之间的关系,评估线粒体基因组的遗传多样性。结果表明:圈养东北虎的遗传多样性高于野生种群,所有遗传变异均为无害。部分圈养个体与野生种群同属一个进化支,且具有野生种群所不包含的遗传变异,可用于实施遗传拯救。此外,圈养种群存在显著的遗传分化,一个与当前野生种群关系很远的分支可能代表未知的地理种群,因此,建议对该远缘分支开展野外来源的追溯,确定其谱系地理学地位和保护价值,使其成为恢复野外历史遗传多样性的后备资源。 展开更多
关键词 东北虎 遗传拯救 线粒体基因组 粪便DNA 遗传多样性
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Chemical Constituents of the Roots of Anemone altaica Fisch. ex C. A. Mey. 被引量:3
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作者 Zhong-Jie ZOU Yue-Sheng DONG Jun-Shan YANG 《Journal of Integrative Plant Biology》 SCIE CAS CSCD 2005年第9期1145-1147,共3页
The roots of Anemone altaica Fisch. ex C. A. Mey. have been used in the treatment of epilepsia, neurasthenia, and arthritis in Chinese folk medicine for a long time. In order to find new and bioactive compounds, the c... The roots of Anemone altaica Fisch. ex C. A. Mey. have been used in the treatment of epilepsia, neurasthenia, and arthritis in Chinese folk medicine for a long time. In order to find new and bioactive compounds, the chemical constituents of the roots of A. altaica were investigated and nine compounds were isolated from the EtOH extract of this plant. On the basis of spectroscopic methods, the structures of these compounds were elucidated as 4-(9H-β-carbolin- 1-yl)-4-oxo-butyric acid (1), carboxymethyl isoferulate (2), isoferulic acid (3), cirsiumaldehyde (4), 5-hydroxy-4-oxo-pentanoic acid (5), triacontane (6), palmic acid (7), β-sitosterol (8), and daucosterol (9). Among them, 1 and 2 were new compounds, and 3 and 4 were obtained from this genus for the first time. 展开更多
关键词 Anemone altaica 4-(9H-β-carbolin-1-yl)-4-oxo-butyric acid carboxymethyl isoferulate chemical constituent cirsiumaldehyde isoferulic acid.
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Social structure and space use of Amur tigers(Panthera tigris altaica)in Southern Russian Far East based on GPS telemetry data 被引量:3
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作者 Jose A.HERNANDEZ-BLANCO Sergei V.NAIDENKO +8 位作者 Maria D.CHISTOPOLOVA Victor S.LUKAREVSKIY Alexey KOSTYRYA Alexandr RYBIN Pavel A.SOROKIN Mikhail N.LITVINOV Andrey K.KOTLYAR Dale G.MIQUELLE Viatcheslav V.ROZHNOV 《Integrative Zoology》 SCIE CSCD 2015年第4期365-375,共11页
To better understand the spatial structure of Amur tigers(Panthera tigris altaica)at the southern edge of their range we fitted 14 tigers(6♀♀and 8♂♂)with 15 GPS-Argos collars between 2008 and 2011 in 2 study sites... To better understand the spatial structure of Amur tigers(Panthera tigris altaica)at the southern edge of their range we fitted 14 tigers(6♀♀and 8♂♂)with 15 GPS-Argos collars between 2008 and 2011 in 2 study sites:the Ussuriskii Reserve of southern Sikhote-Alin and the Land of the Leopard National Park in southwest Primorye,Russian Far East.Fixed kernel estimates of male home ranges were larger than those of female home ranges(P<0.05[mean 95%fixed kernel♀=401±205 km2;mean 95%fixed kernel♂=778±267 km2]).The home range size of females varied greatly,but on average was similar to estimates derived from earlier work further north.Low overlap of adjacent home ranges suggested that females retained exclusive territories.Real core areas of females overlapped only slightly,and remained stable over multiple years.The home ranges of adult males were smaller than those of males to the north,and in contrast to previous studies,high overlap among males indicated the absence of territoriality.Nonetheless,real core areas of males did not overlap,suggesting some spatial separation.In comparison to other tiger populations and other areas of the Russian Far East,the sex ratio in our 2 study areas was highly skewed towards males.We believe this skewed sex ratio resulted in the dissolution of territoriality of males due to an inability to defend individual females,with males resorting to scramble competition for mates.Continued monitoring of these sites to determine whether shifts in the sex ratio might result in a return to male territoriality would provide confirmation of our tentative hypothesis. 展开更多
关键词 Amur tiger GPS-Argos telemetry home range overlap Panthera tigris altaica space use social structure sex ratio
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A comparison of reproductive parameters of female Amur tigers(Panthera tigris altaica)in the wild and captivity 被引量:2
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作者 Jiayin GU Yurong GUO +2 位作者 Philip STOTT Guangshun JIANG Jianzhang MA 《Integrative Zoology》 SCIE CSCD 2016年第1期33-39,共7页
A healthy population of captive Amur tigers might assist recovery of the wild population in Northeast China if individuals were properly prepared and considered suitable for release in the wild.We analyzed the breedin... A healthy population of captive Amur tigers might assist recovery of the wild population in Northeast China if individuals were properly prepared and considered suitable for release in the wild.We analyzed the breeding records of 68 female Amur tigers from 1995 to 2010 in the Hengdaohezi Felid Breeding Center of China and compared the reproductive parameters of this population to wild female Amur tigers.We found that the reproductive parameters of the captive population(the age of first parturition,length of gestation and litter survival rate)were not significantly different from those of wild Amur tigers.Differences in birth date and litter size between wild and captive populations may be caused by management protocols for the captive population or insufficient field data from the wild population.Reproductive parameters of females giving birth after losing a litter were similar to parameters of females that did not lose a litter,except for birth date.These results provide no indication of major problems in using captive females for a breeding program for release of cubs into the wild,but additional information is still needed to assess their suitability. 展开更多
关键词 Amur tiger captive condition Panthera tigris altaica neonatal loss reproductive parameters
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Genetic structure of the Amur tiger(Panthera tigris altaica)population:Are tigers in Sikhote-Alin and southwest Primorye truly isolated? 被引量:2
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作者 Pavel A.SOROKIN Vyatcheslav V.ROZHNOV +3 位作者 Anna U.KRASNENKO Victor S.LUKAREVSKIY Sergey V.NAIDENKO Jose A.HERNANDEZ-BLANCO 《Integrative Zoology》 SCIE CSCD 2016年第1期25-32,共8页
We used molecular genetic analyses to noninvasively identify individual Amur tigers and define subpopulations of tigers in the Russian Far East.We identified 63 individuals after genotyping 256 feces,7 hair and 11 blo... We used molecular genetic analyses to noninvasively identify individual Amur tigers and define subpopulations of tigers in the Russian Far East.We identified 63 individuals after genotyping 256 feces,7 hair and 11 blood samples collected within southern,central and northern Sikhote-Alin,as well as Southwest Primorye.Analysis of nuclear DNA at 9 microsatellite loci demonstrated greater genetic similarity between animals from southern and northern Sikhote-Alin(some 500 km apart)than between animals from Ussuriskii State Nature Reserve and Southwest Primorye(less than 10 km apart at their nearest point),suggesting that a true barrier exists preventing movements of tigers between Southwest Primorye and the southern Sikhote-Alin Mountains. 展开更多
关键词 Amur tiger fecal DNA noninvasive genetic sampling Panthera tigris altaica
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东北虎骨骼标本制作技术
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作者 李邵平 唐松元 +5 位作者 谷祺 宋林 吴耀祥 段文武 吴慧 姜卫星 《湖南林业科技》 2024年第4期91-95,共5页
动物骨骼标本在教学、科研和科普等方面具有极高的科学和研究价值,而东北虎骨骼标本的制作技术对于丰富馆藏和开展野生动物保护、科研、教学等工作具有重要意义。为研究东北虎骨骼标本制作过程时长、药剂使用浓度及浸泡所需时间、制作... 动物骨骼标本在教学、科研和科普等方面具有极高的科学和研究价值,而东北虎骨骼标本的制作技术对于丰富馆藏和开展野生动物保护、科研、教学等工作具有重要意义。为研究东北虎骨骼标本制作过程时长、药剂使用浓度及浸泡所需时间、制作技术流程等内容,本文对东北虎骨骼标本制作中的测量方法、剥皮顺序、骨腔去脂漂白、软组织煮制剔除、骨骼脱脂漂白、浸泡清淘、钢架制作、骨骼组装等关键技术进行了总结,以期为此类大型骨骼标本制作提供技术参考和依据。 展开更多
关键词 东北虎 骨骼标本制作 技术
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广东省人工圈养虎肠道微生物组结构的研究
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作者 王娅妮 李娜 +5 位作者 任照文 孙通宝 张翩 陈晶 陈谭子芃 王晓虎 《广东畜牧兽医科技》 2024年第3期39-47,共9页
为了探究广东省华南虎、孟加拉虎和东北虎肠道菌群结构的组成,本研究利用16S rDNA V1-V9区三代测序对广东省人工圈养的不同虎进行肠道菌群测序比较分析和物种注释,探究其微生物群的组成和丰度。结果显示:圈养健康虎肠道微生物组的优势... 为了探究广东省华南虎、孟加拉虎和东北虎肠道菌群结构的组成,本研究利用16S rDNA V1-V9区三代测序对广东省人工圈养的不同虎进行肠道菌群测序比较分析和物种注释,探究其微生物群的组成和丰度。结果显示:圈养健康虎肠道微生物组的优势菌门为厚壁菌门(Firmicutes)、放线菌门(Actinobacteria)、变形菌门(Proteobacteria)及拟杆菌门(Bacteroidetes);广东省人工圈养华南虎肠道微生物菌群较为健康,不同虎种间的肠道菌群结构没有显著性差异,但基于饮食、环境、状态等条件导致菌群结构还是具有一定的差别,东北虎和孟加拉虎的肠道菌群具有部分较高丰度的潜在致病菌属,表明本次研究调查的孟加拉虎和东北虎存在一定的健康风险,需要密切关注。我们的研究揭示了广东省不同虎种肠道微生物的菌群组成结构,对于这一濒危物种的综合保护和合理圈养有重要意义。 展开更多
关键词 华南虎 孟加拉虎 东北虎 16S rDNA 肠道微生物
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Estimation of body weight in captive Amur tigers(Panthera tigris altaica)
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作者 Qi WANG Chunmei SHI +1 位作者 Dan LIU Guangshun JIANG 《Integrative Zoology》 SCIE CSCD 2022年第6期1106-1120,共15页
So far,there has been no safe and convenient method to weigh the largefierce animals,like Amur tigers.To address this problem,we built models to predict the body weight of Amur tigers based on the fact that body weight... So far,there has been no safe and convenient method to weigh the largefierce animals,like Amur tigers.To address this problem,we built models to predict the body weight of Amur tigers based on the fact that body weight is proportional to body measurements or age.Using the method of body measurements,we extracted the body measurements from 4 different kinds of the lateral body image of tigers,that is,total lateral image,central lateral image,ellipsefitting image,and rectanglefitting image,and then we respectively used artificial neural network(ANN)and power regression model to analyze the predictive relationships between body weight and body measurements.Our results demonstrated that,among all ANN models,the model built with rectanglefitting image had the smallest mean square error.Comparatively,we screened power regression models which had the smallest Akakai information criteria(AIC).In addition,using the method of age,wefitted nonlinear regression models for the relationship between body weight and age and found that,for male tigers,logistic model had the smallest AIC.For female tigers,Gompertz model had the smallest AIC.Consequently,this study could be applied to estimate body weight of captive,or even wild,Amur tigers safely and conveniently,helping to monitor individual health and growth of the Amur tiger populations. 展开更多
关键词 Amur tiger body weight growth curve image analysis Panthera tigris altaica
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Simultaneous polyandry and heteropaternity in tiger(Panthera tigris altaica):Implications for conservation of genetic diversity in captive populations of felids 被引量:3
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作者 LIU Dan MA Yue +5 位作者 LI HuiYi XU YanChun ZHANG Yan DAHMER Thomas BAI SuYing WANG Jian 《Chinese Science Bulletin》 SCIE EI CAS 2013年第17期2230-2236,共7页
Male tigers(Panthera tigris altaica) in captivity copulate alternatively with an estrous female,suggesting a potential for heteropaternity as an effective reproductive strategy to maximize genetic diversity of offspri... Male tigers(Panthera tigris altaica) in captivity copulate alternatively with an estrous female,suggesting a potential for heteropaternity as an effective reproductive strategy to maximize genetic diversity of offspring.We analyzed microsatellites to test and compare the genetic output of multiple male mating(simultaneous polyandry) and single male mating(monogamy) with a female in a captive population.Simultaneous polyandry resulted in heteropaternity in 66.7% observed litters.No significant differences between parental populations and between offspring populations were detected in the number of alleles(A),expected heterozygosity(H e),number of effective alleles(N e) per locus and standard individual heterozygosity(SH)(P>0.05 for all 4 indexes).Comparisons showed no significant reduction of A,H o,H e and SH from parental population to offspring population for the two mating modes(P>0.05) except for SH in polyandrous families(P=0.029).However,such reduction was equivalent to single mating families when the influence of relatedness was eliminated using effective SH(E SH)(P>0.05).These results highlight an alternative strategy for managing captive populations of tiger and other wild felids in which animals are combined at one location allowing for copulation by multiple males to encourage heteropaternity in favor of maintained genetic diversity among offspring. 展开更多
关键词 遗传多样性保护 圈养种群 猫科动物 东北虎 一夫一妻制 等位基因数 Pgt 杂合度
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阿尔泰银莲花根际土壤微生物多样性研究 被引量:2
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作者 王晶 张会萍 +6 位作者 苏晓 付前进 李学榜 刘凤琴 邵毅贞 陈云 袁志良 《广西植物》 CAS CSCD 北大核心 2023年第8期1467-1477,共11页
为了解野生和栽培阿尔泰银莲花根际土壤微生物多样性的差异,该研究采用Illumina MiSeq高通量测序技术对野生和栽培阿尔泰银莲花根际土壤微生物的群落组成和多样性进行探究。结果表明:(1)野生阿尔泰银莲花根际土壤的真菌多样性显著高于... 为了解野生和栽培阿尔泰银莲花根际土壤微生物多样性的差异,该研究采用Illumina MiSeq高通量测序技术对野生和栽培阿尔泰银莲花根际土壤微生物的群落组成和多样性进行探究。结果表明:(1)野生阿尔泰银莲花根际土壤的真菌多样性显著高于栽培阿尔泰银莲花(P<0.05),而细菌多样性差异不显著(P>0.05);NMDS分析结果显示,野生和栽培阿尔泰银莲花根际土壤真菌群落结构差异更显著。(2)细菌9566个可操作分类单元(OTUs)涉及39门127纲315目500科886属,真菌2670个OTUs涉及15门57纲138目293科597属。在门水平上,细菌群落中的变形菌门、酸杆菌门、放线菌门及真菌群落中的担子菌门、子囊菌门、被孢霉门均为野生和栽培阿尔泰银莲花根际土壤优势菌门,但其相对丰度在不同生长方式下存在差异。(3)环境因子关联分析(RDA)结果显示,土壤有机质是影响土壤细菌群落的主要因子(P<0.05),土壤pH、碱解氮和有效磷是影响真菌群落的主要因子(P<0.05)。综上认为,野生和栽培下的阿尔泰银莲花根际土壤微生物群落组成和多样性存在显著差异,这种差异可能与不同生长条件下的土壤理化性质存在密切的联系,该研究结果对阿尔泰银莲花科学种植以及土壤改良具有一定意义。 展开更多
关键词 阿尔泰银莲花 土壤微生物 高通量测序 群落结构 物种多样性
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东北虎栖息地适宜性研究概况与展望 被引量:1
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作者 郭媛 张士芳 +5 位作者 魏丹 付晓宇 常旭东 李海军 刘应竹 朱世兵 《黑龙江科学》 2023年第22期6-9,共4页
东北虎栖息地质量是制约其种群数量恢复的关键因素之一,对栖息地进行质量评估是开展东北虎种群保护的重要保证。近些年,随着森林生态系统的恢复重建,我国野生东北虎数量大幅增长,东北虎栖息地质量提升迫在眉睫。通过文献收集法,整理了... 东北虎栖息地质量是制约其种群数量恢复的关键因素之一,对栖息地进行质量评估是开展东北虎种群保护的重要保证。近些年,随着森林生态系统的恢复重建,我国野生东北虎数量大幅增长,东北虎栖息地质量提升迫在眉睫。通过文献收集法,整理了我国学者近年来的调查研究成果,归纳总结了影响栖息地适宜性的重要因素,即地理环境、植被类型、猎物种群及人为干扰,指出当前存在的问题,探讨了东北虎生态与保护研究的发展方向,以期为东北虎栖息地的恢复及生态廊道构建提供参考。 展开更多
关键词 东北虎 适宜性 栖息地 恢复
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基于轻量化YOLOX算法的东北虎检测 被引量:1
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作者 于文华 谢永华 《野生动物学报》 北大核心 2023年第4期760-767,共8页
以大型哺乳动物东北虎(Panthera tigris altaica)为例,通过使用圈养东北虎监测影像数据集(ATRW),采用YOLOX算法对东北虎进行目标检测研究,检测速度为87.59张/s,0.50阈值准确率(mAP_(0.50))为97.32%,0.75阈值准确率(mAP_(0.75))为75.10%... 以大型哺乳动物东北虎(Panthera tigris altaica)为例,通过使用圈养东北虎监测影像数据集(ATRW),采用YOLOX算法对东北虎进行目标检测研究,检测速度为87.59张/s,0.50阈值准确率(mAP_(0.50))为97.32%,0.75阈值准确率(mAP_(0.75))为75.10%,模型总参数量为8.938×10^(6)。通过筛选无锚框算法,对选出的YOLOX算法进行轻量化、添加注意力机制及网络损失函数的优化,优化后的算法检测速度提升1.74张/s,mAP_(0.50)准确率提升1.02个百分点,mAP_(0.75)准确率提升1.53个百分点,模型的总参数量减少18.47%。算法改进后,在提升识别准确率的同时,有效降低了检测算法依托硬件的需求,为东北虎的野外行为研究、保护生物多样性及东北虎的野外相关数据收集提供了检测算法。 展开更多
关键词 YOLOX算法 目标检测 轻量化 东北虎
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阿尔泰瑞香化学成分及药理作用研究进展
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作者 刘淑兰 李进 《新疆师范大学学报(自然科学版)》 2023年第2期57-68,共12页
阿尔泰瑞香(Daphne Altaica Pall.)为我国民间传统中药材,可治疗肺癌、胃癌、气管炎、风寒感冒等疾病。国内外学者从阿尔泰瑞香中分离的化学成分主要包括香豆素类、黄酮类、萜类、木脂素类、甾体类、酚酸类及其他成分。研究表明,阿尔泰... 阿尔泰瑞香(Daphne Altaica Pall.)为我国民间传统中药材,可治疗肺癌、胃癌、气管炎、风寒感冒等疾病。国内外学者从阿尔泰瑞香中分离的化学成分主要包括香豆素类、黄酮类、萜类、木脂素类、甾体类、酚酸类及其他成分。研究表明,阿尔泰瑞香具有抗癌、抗炎、抗氧化、活血、止痛等多种药理作用。阿尔泰瑞香化学成分及含量是发挥其药效的重要基础,但相关研究较少,今后还需大量实验明确化学成分,确定其质量标准,发现新化合物以及探索更多的药理活性。 展开更多
关键词 阿尔泰瑞香 香豆素类 黄酮类 萜类 木脂素类 抗癌 抗炎 抗氧化
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结合指导学习和特征擦除的东北虎重识别研究
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作者 翟冰 戴天虹 《野生动物学报》 北大核心 2023年第2期297-304,共8页
东北虎(Panthera tigris altaica)重识别对于东北虎的行为研究以及保护具有重要意义,针对在自然环境中东北虎难以被重新识别的问题,提出了一种结合指导学习和特征擦除的东北虎重识别方法。设计了一个包括全局流和局部流的双流网络,局部... 东北虎(Panthera tigris altaica)重识别对于东北虎的行为研究以及保护具有重要意义,针对在自然环境中东北虎难以被重新识别的问题,提出了一种结合指导学习和特征擦除的东北虎重识别方法。设计了一个包括全局流和局部流的双流网络,局部流以分割后的前景图作为输入,使网络更关注前景部分,全局流以原图作为输入,通过局部流指导全局流学习细粒度特征,同时将模型最后全连接层(FC)的各类别权重参数之间的差异作为指导进行特征擦除,以擦除后的特征向量训练网络,从而增强特征向量中更多元素的辨别能力,最后在测试阶段只使用全局流。在野外东北虎重识别(ATRW)数据集上对该方法进行评估,在单摄像机条件下,m AP达到92.1%;在交叉摄像机条件下,m AP达到72.9%,试验结果表明方法有效。 展开更多
关键词 东北虎重识别 双流网络 细粒度特征 特征擦除
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老爷岭南部狍冬季移动、卧息生境选择及其适宜性评价 被引量:5
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作者 刘艳华 牛莹莹 +4 位作者 周绍春 张子栋 梁卓 杨娇 鞠丹 《生态学报》 CAS CSCD 北大核心 2021年第17期6913-6923,共11页
在动物生境研究中,移动生境和卧息生境是生境研究的焦点。开展移动生境和卧息生境选择,并在此基础上进行生境评价,有利于深入了解动物对移动和卧息生境条件的需求,制定科学合理的栖息地保护计划。以东北虎(Panthera tigris altaica)的... 在动物生境研究中,移动生境和卧息生境是生境研究的焦点。开展移动生境和卧息生境选择,并在此基础上进行生境评价,有利于深入了解动物对移动和卧息生境条件的需求,制定科学合理的栖息地保护计划。以东北虎(Panthera tigris altaica)的主要猎物物种之一——狍(Capreolus pygargus)为研究对象,于2017—2019年冬季积雪覆盖期在老爷岭南部通过随机布设28个大样方和84条用于足迹链跟踪的样线收集狍的移动点和卧息点信息,再结合近年来收集的东北虎出现点,利用广义可加模型(GAM)和最大熵模型(MaxEnt)进行狍移动、卧息生境选择及评价研究。移动生境选择研究表明,狍在移动的过程中偏好选择坡度小、距农田距离>500 m、远离道路、居民点和低海拔或较高海拔的区域;移动生境评价分析表明,移动适宜和次适宜生境面积之和为1318.16 km^(2),占研究区域面积的51.28%,当加入虎活动点影响因子后,狍移动适宜和次适宜生境面积之和为901.52 km^(2),适宜和次适宜生境面积之和减少了31.61%。狍卧息生境选择研究表明,水源、农田、道路和雪深是影响狍卧息的关键因素,其中雪深对狍卧息生境选择的贡献率达到70.13%;卧息生境评价表明,卧息适宜和次适宜生境面积之和为1243.77 km^(2),占研究区域面积的48.39%,当加入虎出现点因子后,适宜生境和次适宜生境面积之和减少了61.00%,仅为485.02 km^(2)。研究认为,虎的出现对狍移动和卧息生境选择均产生影响,虎的活动及捕食行为可能会减少狍的活动范围和频次,狍远离虎活动区域卧息休息,压缩了狍适宜卧息的空间。 展开更多
关键词 狍(Capreolus pygargus) 东北虎(Panthera tigris altaica) 广义可加模型 最大熵模型 生境选择 生境评价
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吉林省东北虎的调查 被引量:39
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作者 李彤 蒋劲松 +3 位作者 吴志刚 韩晓东 吴景才 杨兴家 《兽类学报》 CAS CSCD 北大核心 2001年第1期1-6,共6页
经过 8年的调查研究 ,确定了东北虎在吉林省的分布区有 3处 ,数量为 7~ 9只。即大龙岭分布区 3~ 5只 ,哈尔巴岭分布区 1只 ,张广才岭分布区 3只。东北虎的适宜生境为海拔80 0~ 110 0m的中低山 ;人口压力在 15人 /km2 以下 ,被捕食动... 经过 8年的调查研究 ,确定了东北虎在吉林省的分布区有 3处 ,数量为 7~ 9只。即大龙岭分布区 3~ 5只 ,哈尔巴岭分布区 1只 ,张广才岭分布区 3只。东北虎的适宜生境为海拔80 0~ 110 0m的中低山 ;人口压力在 15人 /km2 以下 ,被捕食动物野猪、狍、马鹿的密度在2 5只 /km2 以上。林型为以柞木为主的阔叶混交林 ,林龄为中成林。 展开更多
关键词 东北虎 分布区 种群数量 吉林
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