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1.
河南昆虫、蜘蛛、蜱螨地理分布的多元相似性聚类分析   总被引:2,自引:0,他引:2  
申效诚  任应党  王爱萍  张书杰 《生态学报》2010,30(16):4416-4426
河南省的昆虫、蜘蛛、蜱螨种类共8637种,隶属32目551科3967属。使用多元相似性聚类分析法(MSCA)对全省11个生态区域间的关系进行分析,总相似性系数0.184,表明分布很不均匀,在0.3的相似性水平上,全省分为4个地理分布区:平原盆地区、西北山地丘陵区、伏牛山区和桐柏大别山区。分析了分类阶元、区系成分、不同类群、种类规模、分布地规模对相似性聚类关系的影响,结果显示,属级水平和种级一样,能够揭示省级地理区域内的相似性聚类关系,科级水平将适合更大的地理区域;生物类群是对相似性聚类结构影响最大的参量,保证多类群的参与,是揭示整体规律的关键;在多类群参与的前提下,种类和分布地不是敏感的因素,合适的种类抽样同样能得到满意的结果,分布地的少量增减,也只会引起相似性系数的轻微变动。  相似文献   

2.
中国昆虫区系的多元相似性聚类分析和地理区划   总被引:3,自引:0,他引:3  
为了总结分析中国昆虫的分布规律, 为昆虫地理区划提出依据, 作者2008年创建了新的多元相似性聚类分析方法, 它与传统的聚类分析方法的主要不同是直接计算任意多个地区之间的相似性系数, 从而摈弃原来的合并环节。我们应用这种方法对中国823科17 018属93 662种昆虫的分布进行了定量分析。当种级水平相似性系数分别为0.19和0.14时, 全国64个基础地理单元聚类为20个小单元群和9个大单元群。根据聚类分析结果, 提出我国第一个由定量分析产生的9个昆虫区20个昆虫亚区的中国昆虫地理区划的初步方案。西北昆虫区、 东北昆虫区、 华北昆虫区、 青藏昆虫区稳定地组成中国北方昆虫大区, 江淮昆虫区、 华中昆虫区、 西南昆虫区、 华东昆虫区、 华南昆虫区稳定地组成中国南方昆虫大区。江淮昆虫区的设立是因为这里多平原和丘陵, 为重要农业区, 昆虫区系简单, 种类显著少于华东、 华中、 华南昆虫区, 而和华北昆虫区相当; 包括台湾在内的华东昆虫区是昆虫多样性最丰富地区之一, 显著高于邻近的华北、 江淮、 华南昆虫区。最后, 对昆虫地理定量分析中的重要环节进行讨论, 还对今后昆虫区系调查的薄弱地区提出建议。这项研究证明多元相似性聚类分析方法是简便、 快捷、 实用的, 能够在更广泛的范围应用, 这预示着生物地理学研究将会由定性研究进入到定量研究阶段。  相似文献   

3.
申效诚  张保石  张锋  刘新涛 《生态学报》2013,33(21):6795-6802
蜘蛛是一类种类繁多、数量巨大、分布广泛的捕食性生物。至2012年底,全世界共有蜘蛛43678种(包括亚种),隶属于112科3898属。科、属、种3个分类阶元的分布域非常悬殊,90%的种分布在一个界内,90%的科是跨界分布或全球分布。按行政区域,亚洲种类较多,欧洲较少,南极洲没有蜘蛛记录;按动物地理区域,古北界和新热带界较多,新北界较少。根据地理条件、生态条件和蜘蛛的分布状况,将全球陆地分为53个基础地理单元,用申效诚等新近提出的相似性通用公式和据此创立的多元相似性聚类分析方法,分别对属、种两级的分布进行分析,得到两个聚类结构相同、聚类关系合理的支序图,而且属级的支序图层次更为分明,在相似性水平为0.32时,53个基础地理单元聚为17个小单元群,在0,22水平上,又聚为8个大单元群。这些大、小单元群的组成单元地域相邻相连,生态条件相对一致,可以作为蜘蛛地理区划的界、亚界两个层级。和华莱士主要以哺乳动物建立的世界动物地理区划相比,主要差异是:1、古北界东、西两部分差异显著,可分设两界;2、新西兰和澳洲大陆相似性较低,可单独设界;3、新几内亚和太平洋岛屿与澳洲大陆的关系远于和东洋界的关系,华莱士线在两界间的作用似乎不存在; 4、新热带界的中美地区似乎属于新北界更为合适,并由此产生了南北美洲间的紧密联系;5、新北界与古北界的相似性关系弱于与新热带界的关系,全北界的概念几近消失。前两点差异可以从地球板块构造的变动得到解释,第3、5个差异已在植物和其它生物类群得到佐证,第4个差异尚不稳定,需要更多类群的比较与分析。使用多元相似性聚类分析方法对于如此典型的点状分布的生物类群和如此海量的数据,能够得到如此精细的,既符合地理学、统计学的逻辑,又符合生物学、生态学逻辑的定量分析结果,这在国内外都是首次成功尝试,其简便性和合理性将会促使在其它类群中的应用。  相似文献   

4.
贵州几种常见杜鹃花的随机扩增多态性DNA(RAPD)研究   总被引:10,自引:0,他引:10  
采用RAPD方法对贵州7个常见杜鹃花基因型进行分析,建立了它们的指纹图谱。从60个随机引物中筛选出的10个有效引物共产生49条DNA片段,大小分布在0.1~3.0kh之间,其中28个条带具有遗传多态性,约占总数的57.14%,平均每个引物扩增的DNA带数为4.9条。7个杜鹃花的遗传相似性分析表明,各基因型之间的J相似性系数分布在0.63~0.90之间.平均相似性系数为0.765。应用NTSYSpc软件进行聚类.将聚类结果转化为7个杜鹃花基因型之间的遗传关系树型图。7个杜鹃花基因型明显地聚成A、B两大类,A类包括:1号(锈叶杜鹃)、6号(红花露珠杜鹃)和7号(露珠杜鹃)3个基因型;B类包括:2号(大白杜鹃)、4号(杜鹃)、5号(红马缨杜鹃)和3号(桃叶杜鹃)4个基因型。  相似文献   

5.
昆虫区系多元相似性分析方法   总被引:4,自引:0,他引:4  
申效诚  孙浩  赵华东 《生态学报》2008,28(2):849-854
由植物学领域首先提出的相似性概念已广泛应用于动植物区系地理研究以及生物学、生态学等诸多自然学科乃至社会科学领域.根据Jacard提出的二元相似性系数公式SI=C/(A B-C)和Sprensen提出的二元相似性系数公式SI=2C/(A B),分别推导出2个计算多元相似性系数的数学表达式,SIJab…n=[(∑Hij)2/n (∑Hijk)3/n … Hab…n]/[∑Si-∑Hij-2∑Hijk-…-(n-1)Hab…n]和 SISab…n=[2(∑Hij)2/n (3∑Hijk)3/n … nHab…n]/ ∑Si,并用中国夜蛾广布种类在中国7个动物地理区的分布资料为例进行验证,从而可以直接从整体角度和宏观规模上简便、快捷地考量多个系统间的亲疏程度和相似关系.建议在以相似性为基础的聚类分析中,不必再先把2个系统合并成一个新系统后,再和第3个系统比较,而可直接计算多个系统的相似性系数,以避免由于合并带来的信息损失.还讨论了应该提高Sprensen公式0.5的显著性标准,以使同一组数据的两种计算结果趋向一致.  相似文献   

6.
黄土高原洛河流域蝗虫群落排序及环境因素分析   总被引:7,自引:1,他引:6  
应用相似性分析、主成分(PCA)分析及多元逐步回归等方法比较了洛河流域黄土高原不同地区蝗虫的群落结构。结果显示:吴旗和志丹、富县和黄陵的相似性均很高,甘泉则更加靠近富县和黄陵,相似性分析的结果反映了该地区蝗虫群落在地理上的分布规律。对各地点气候因素和蝗虫群落所进行的主成分分析,结果非常理想,三维主成分的累计方差贡献率分别达到了96.22%和92.06%。通过多元逐步回归发现,促进蝗虫发生的气候因子有5~9月平均气温、5~9月平均总降水、年平均总降水和年平均日照时数,抑止因子有5~9月最低降水等;促进蝗虫发生的植被因素有草本植物高度多样性、树木盖度、豆科优势度和其他科优势度等几个因素,抑止因素有禾本科优势度、莎草科优势度等。  相似文献   

7.
东北地区部分大型藓类植物遗传多样性的RAPD研究   总被引:1,自引:1,他引:0  
李晶  沙伟 《植物研究》2008,28(6):689-692
采用RAPD标记构建了东北地区20种大型藓类植物的系统关系。从200个随机引物中筛选出清晰且多态性高的7个引物,共产生了82条DNA片段,其中79条谱带具有遗传多态性,约占96.34%,平均每个引物扩增的DNA片段数为11.71条。采用NTSYS-pc数据分析软件,计算Nei氏相似性系数,建立了UPGMA聚类图。结果表明:以遗传相似性系数0.27为界限划分,可将20种苔藓植物分为二大类,即泥炭藓类和真藓类。以遗传相似性系数0.42为界限划分,可将20种苔藓植物划分为四大类群,即泥炭藓类、顶蒴单齿亚类、顶蒴双齿亚类和侧蒴双齿类。从整个聚类图可以看出,泥炭藓类是较原始的类群,而金发藓类是较进化的类群,这一结果和大多数苔藓植物经典分类系统相同。  相似文献   

8.
利用ISSR分子标记对9个观叶福禄桐品种进行遗传多样性和亲缘关系分析,从100条引物中筛选出9条稳定、多态性高的引物用于PCR扩增,共获得70条带,其中多态性条带61条,多态百分率为87.14%。聚类结果显示,品种间相似性系数为0.346 9-0.816 3,聚类结果与品种间的地理来源紧密相关,从外观形态上比较,亲缘性较近的叶形和株型相似性较高;观叶福禄桐各品种间基因型差异较小,亲缘关系较近,遗传基础相对较窄。  相似文献   

9.
云南蚤类区系及分布特征   总被引:5,自引:0,他引:5  
【目的】在收集汇总以往野外调查资料以及已经发表的历史文献资料基础上,归纳云南蚤类的分布特点,分析云南地理小区对蚤类的影响。【方法】在实地采集和补充文献记录基础上,对收集到的蚤类进行系统分类整理;运用SPSS13.0的主成分分析及系统聚类对数据进行处理。【结果】本研究共记录云南蚤类9科45属144种,其中古北种15种,东洋种 108种,东洋、古北两界兼有种15种,广布种6种。144种蚤中,属于云南特有蚤类有75种;横断山中部小区记载蚤类122种,横断山南部小区26种,滇东高原小区41种,滇西高原小区28种,滇南山地小区25种。主成分分析和聚类分析结果基本一致,均可聚为两类:一类为横断山南部小区、滇南山地小区、滇西高原小区及滇东高原小区; 另一类为横断山中部小区。【结论】云南省蚤类分布明显受到地理小区环境的影响。云南省蚤类昆虫种类繁多,蚤类的自然分布受到云南省特定地形地貌影响。  相似文献   

10.
云南省两栖动物地理分布格局的聚类分析   总被引:1,自引:0,他引:1  
邝粉良  刘宁  冯子山 《四川动物》2007,26(2):445-447
为了量化云南省两栖动物地理分布格局及其相似性,对云南省102种两栖动物在地理小区的分布格局尺度上进行了聚类分析。建立物种有无分布的二元数据列联表,利用联合系数表示每两个地理小区内两栖动物的相似程度,以类平均法进行了聚类分析。结果表明,云南两栖动物可以归类为两大类群,相邻动物地理小区相似程度较高,南北差异显著。云南两栖动物地理分布格局与地势的阶梯变化基本一致。受地形、河流和气候的影响,分布格局的纬度变化规律不明显。在此基础上对结果与地理区划进行了对比。  相似文献   

11.
刘嘉恒  路纪琪 《兽类学报》2020,40(3):271-281
中国的地形复杂、地貌多样,动物的地理分布亦表现出明显的区域间差异。本研究通过新近文献调研,获知中国现生哺乳动物计692种(隶于13目56科246属);进而建立物种及其地理分布数据库。采用多元相似性聚类分析(multivariate similarity clustering analysis, MSCA)方法,探讨了中国哺乳动物的地理分布特征。结果表明:(1)中国的现生哺乳动物可划分为176个调查地理单元(investigated geographical unit, IGU),进而归并为63个基础地理单元(basic geographical unit, BGU);(2)当相似性系数取0.31、0.25和0.15时,上述63个BGU可分别归并为10个、7个和2个基础地理单元群;据此可对中国的哺乳动物地理分布作出2界7区10亚区的3级区划。本文建议,世界动物地理区划中古北界与东洋界在中国境内的分界线走向为:南迦巴瓦峰西部-玛卿岗日-秦岭北部-黄土高原南缘-大别山-淮河南-长江中下游一线。  相似文献   

12.
Aim The similarity between parasite assemblages should decrease with increasing geographic distance between them, increasing dissimilarity in environmental conditions, and/or increasing dissimilarity of the local host fauna, depending on the dispersal abilities of the parasites and the intimacy of their associations with the host. We tested for a decay in the similarity of gamasid mite assemblages parasitic on small mammals with increasing geographic, ‘environmental’ and ‘host faunal’ (= ‘host’) distances. Location We used data on assemblages of haematophagous gamasid mites (superfamily Dermanyssoidea) parasitic on small mammals (Insectivora, Lagomorpha and Rodentia) from 26 different regions of the northern Palaearctic. Methods Similarity in mite assemblages was investigated at the compound community level across all regions, and at the component community level, across populations of the same host species for each of 11 common host species. Similarity between pairs of mite communities was estimated using both the Jaccard and the Sorensen indices. Environmental distance was estimated as the dissimilarity between locations in a composite measure of climatic variables, and host faunal distance was simply taken as the reciprocal of indices of similarity between the composition of host faunas in different locations. Generalized Linear Models (GLM) and Akaike's Information Criterion were used to select the best model of decay in similarity as a function of geographic, ‘environmental’ and ‘host faunal’ distances. Results Overall, despite slight differences among host species, the similarity in mite assemblages decreased with both increasing ‘environmental’ distance and increasing ‘host faunal’ distance, but was generally unaffected by geographic distance between regions. The similarity of component communities of gamasid mites among host populations was determined mainly by similarity in the physical environment, whereas that of compound communities varied mainly with host‐species composition. Main conclusions Our results indicate that the general decay in community similarity with increasing geographic distances does not apply to assemblages of gamasid mites; it is possible that they can overcome great distances by means of passive dispersal (either by phoresy or wind‐borne), or more likely they occur wherever their hosts are found as a result of tight cospeciation in the past. Mite assemblages on small mammalian hosts seem to be affected mainly by local environmental conditions, and, to a much lesser extent, by the species composition of local host communities.  相似文献   

13.
根据 FDA 和 CFDA 口服固体制剂溶出度试验技术指导原则的要求,为防止仿制药一致性评价过程中相似因子(f2)法的滥用和 不恰当应用,采用样本数据实例演示的方式说明多变量置信区间法和模型依赖法作为补充手段在溶出曲线相似性比较和 BE 风险预评估中 的重要性。  相似文献   

14.
15.
婴幼儿配方奶粉菌落总数检验中不确定度的评定   总被引:3,自引:0,他引:3  
分析样品中菌落总数不确定度的来源,采用合并样品标准差的方法来评定菌落总数的不确定。研究表明:实验中的扩展不确定度为0.046%,采用此法适合于菌落总数检验结果的评定。且该法简便,适合于每一个样本的检验结果,随着检验结果的不断增加,可随时加入到合并样本中,重新计算合并样本标准差,更新不确定度的取值范围。  相似文献   

16.
《动物分类学报》2017,(1):34-45
Geometric morphometrics (GM) is an important method of shape analysis and increasingly used in a wide range of scientific disciplines.Presently,a single character comparison system of geometric morphometric data is used in almost all empirical studies,and this approach is sufficient for many scientific problems.However,the estimation of overall similarity among taxa or objects based on multiple characters is crucial in a variety of contexts (e.g.(semi-)automated identification,phenetic relationships,tracing of character evolution,phylogenetic reconstruction).Here we propose a new web-based tool for merging several geometric morphometrics data files from multiple characters into a single data file.Using this approach information from multiple characters can be compared in combination and an overall similarity estimate can be obtained in a convenient and geometrically rigorous manner.To illustrate our method,we provide an example analysis of 25 dung beetle species with seven Procrustes superimposed landmark data files representing the morphological variation of body features:the epipharynx,right mandible,pronotum,elytra,hindwing,and the metendosternite in dorsal and lateral view.All seven files were merged into a single one containing information on 649 landmark locations.The possible applications of such merged data files in different fields of science are discussed.  相似文献   

17.
Prodrugs of L-selenocysteine have potential utility in cancer chemoprevention. This study reports the efficacy of three selenazolidine-4(R)-carboxylic acids, (2-unsubstituted, 2-oxo, and 2-methyl derivatives; SCA, OSCA, and MSCA, respectively) against tobacco-related lung tumorigenesis in a mouse model. Seven days after initiation of an AIN-76A diet supplemented with sodium selenite (5 ppm Se), L-selenomethionine (3.75 ppm Se), Se-methyl-L-selenocysteine (3 ppm Se), L-selenocystine (15 ppm Se), SCA (15 ppm Se), OSCA (15 ppm Se), or MSCA (15 ppm Se), mice received 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK; 10 micromol, i.p.). After an additional 16 weeks on the diets, two compounds, OSCA and selenocystine, significantly reduced lung adenoma multiplicity from 7.2 tumors per mouse in the NNK group to 4.5 and 4.6 tumors per mouse, respectively. Neither selenium concentration nor glutathione peroxidase activity in either RBCs or liver served as surrogate indicators of tumor reduction. Hepatic selenium levels were significantly elevated by all selenium-containing compounds except Se-methyl-L-selenocysteine and SCA; RBC selenium levels by all except sodium selenite and MSCA. With the exception of L-selenomethionine, RBC glutathione peroxidase activity was increased along with the elevated selenium levels. Hepatic glutathione peroxidase activity was elevated by all Se-compounds except SCA. The two compounds showing significant tumor reduction (OSCA and selenocystine) were the only two compounds that showed ubiquity of changes, elevating both selenium levels and GPx activity in both liver and RBC.  相似文献   

18.
Prodrugs of L ‐selenocysteine have potential utility in cancer chemoprevention. This study reports the efficacy of three selenazolidine‐4(R)‐carboxylic acids, (2‐unsubstituted, 2‐oxo, and 2‐methyl derivatives; SCA, OSCA, and MSCA, respectively) against tobacco‐related lung tumorigenesis in a mouse model. Seven days after initiation of an AIN‐76A diet supplemented with sodium selenite (5 ppm Se), L ‐selenomethionine (3.75 ppm Se), Se‐methyl‐L ‐selenocysteine (3 ppm Se), L ‐selenocystine (15 ppm Se), SCA (15 ppm Se), OSCA (15 ppm Se), or MSCA (15 ppm Se), mice received 4‐(methylnitrosamino)‐1‐(3‐pyridyl)‐1‐butanone (NNK; 10 μmol, i.p.). After an additional 16 weeks on the diets, two compounds, OSCA and selenocystine, significantly reduced lung adenoma multiplicity from 7.2 tumors per mouse in the NNK group to 4.5 and 4.6 tumors per mouse, respectively. Neither selenium concentration nor glutathione peroxidase activity in either RBCs or liver served as surrogate indicators of tumor reduction. Hepatic selenium levels were significantly elevated by all selenium‐containing compounds except Se‐methyl‐L ‐selenocysteine and SCA; RBC selenium levels by all except sodium selenite and MSCA. With the exception of L ‐selenomethionine, RBC glutathione peroxidase activity was increased along with the elevated selenium levels. Hepatic glutathione peroxidase activity was elevated by all Se‐compounds except SCA. The two compounds showing significant tumor reduction (OSCA and selenocystine) were the only two compounds that showed ubiquity of changes, elevating both selenium levels and GPx activity in both liver and RBC. © 2005 Wiley Periodicals, Inc. J Biochem Mol Toxicol 19:396‐405, 2005; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/jbt.20105  相似文献   

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