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蚯蚓野外采样方法评述 总被引：1，自引：0，他引：1
蚯蚓作为土壤生态系统的关键组成部分,不但可以改善土壤结构,而且与许多生物化学养分循环直接相关,对土壤质量改善和土壤生产力提高起到至关重要的作用.然而,蚯蚓野外采样方法的系统研究和评估还比较缺乏,在国内尤其少见.本文综述了目前国内外常见蚯蚓野外采样方法的操作过程、优缺点、有效性以及对蚯蚓种群特征研究结果可能产生的影响,认为在允许扰动土壤的区域,利用驱虫剂与手拣法相结合进行蚯蚓采样能够较为准确地反映蚯蚓种群和生物量的真实特征;在不能扰动土壤的区域异硫氰酸烯丙酯(AITC)溶液方法是最佳选择. 相似文献
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蚯蚓作为土壤生态系统的关键组成部分,不但可以改善土壤结构,而且与许多生物化学养分循环直接相关,对土壤质量改善和土壤生产力提高起到至关重要的作用.然而,蚯蚓野外采样方法的系统研究和评估还比较缺乏,在国内尤其少见.本文综述了目前国内外常见蚯蚓野外采样方法的操作过程、优缺点、有效性以及对蚯蚓种群特征研究结果可能产生的影响,认为在允许扰动土壤的区域,利用驱虫剂与手拣法相结合进行蚯蚓采样能够较为准确地反映蚯蚓种群和生物量的真实特征;在不能扰动土壤的区域异硫氰酸烯丙酯(AITC)溶液方法是最佳选择. 相似文献
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蚯蚓是陆地生态系统中重要的大型土壤动物之一,其种类组成、种群大小及群落结构在一定程度上可以反映当地的土壤状况.常用的蚯蚓采样方法如手挖、电击法、福尔马林法、芥末法、异硫氰酸丙烯酯法存在很多差异,各方法都存在一定缺点.本研究应用茶枯溶液进行蚯蚓采样,操作简便易行.试验结果表明,茶枯法在荷木林、马占林、马尾松林的单位面积所驱赶出的蚯蚓个体数依次为62.1、70.3、96.2 number m-2,各林区采样效率依次为80.1%、70.9%、75.8%;3林区平均个体数采样效率为75.3%.除内栖类蚯蚓西土寒宪蚓外,其他蚯蚓种均能完全被驱赶采样;未能采样蚯蚓大部分为西土寒宪蚓幼体;在进入干季11月份采样效率显著降低. 相似文献
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罗庆睿;李红阳;肖艳兰;字玉奋;段昌群;刘嫦娥 《应用生态学报》2025,(2):569-577
大型土壤动物蚯蚓对土壤生态功能具有重要影响。本研究采集了云南省6个气候带的1984个蚯蚓样本,探讨云南省蚯蚓的空间分布特征。结果表明：神女辛石蚓和梯形流蚓为云南省优势蚯蚓物种。云南省温带地区的蚯蚓物种最多,其次为北热带、北亚热带、中亚热带、高原气候带和南亚热带;蚯蚓密度表现为高原气候带(70.7 ind·m-2)>温带(62.4 ind·m-2)>北亚热带(55.9 ind·m-2)>北热带(37.7 ind·m-2)>中亚热带(37.7 ind·m-2)>南亚热带(22.7 ind·m-2);蚯蚓生物量为北亚热带(27.4 g·m-2)>北热带(24.5 g·m-2)>南亚热带(19.1 g·m-2)>温带(17.0 g·m-2)>中亚热带(15.3 g·m-2)>高原气候带(12.5 g·m-2)。不同的气候带类型直接影响蚯蚓生物量,此外,土壤含水率、有机质、全氮等土壤特性对蚯蚓群落也有显著影响。 相似文献
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电击法采集蚯蚓对环境相对友好,但电击效率可能因立地条件和蚯蚓类群而变化,进而限制了电击法的广泛应用。本研究于2017年11月上旬采用电击法配合手拣法对长白山3个不同森林发育阶段的杨桦林的蚯蚓群落进行了调查,分析了森林发育阶段、蚯蚓生态型、蚯蚓种群大小以及发育阶段、土壤温湿度状况等对电击效率的影响。结果表明:不同森林发育阶段蚯蚓的电击效率不同,其中40年生杨桦林电击效率最高,其蚯蚓数量和生物量电击效率分别为68.5%和57.4%;表栖型的诺登爱胜蚓(Eisenia nordenskioldi)活动能力最强,电击效率高达100%;内-深栖型的长白山杜拉蚓(Drawida changbaishanensis)在实验期间处于蜷曲休眠状态,电击效率低至0;而内栖型的安德爱胜蚓(Eisenia andrei)的电击效率为22.2%～58.3%;安德爱胜蚓种群大小与电击效率无明显的相关关系(其中,数量:r=0.139,P=0.381,生物量:r=0.025,P=0.877);安德爱胜蚓成体的电击效率显著高于幼体(P=0.014);土壤温度对电击效率有显著的影响,当土壤温度低于6℃时电击效率为0;当土... 相似文献
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通过在华北低肥力农田生态系统进行的不同土壤培肥试验 ,研究了不同秸秆还田方式和施肥措施对土壤中蚯蚓种群的影响。研究结果表明 :一年中 5次调查到的蚯蚓属于同一个目——后孔寡毛目 ,3科、6属、7种 ;在 7种蚯蚓中 ,天锡杜拉蚓Drawida gisti是该地区较低肥力土壤中的蚯蚓优势种。蚯蚓种群数量的季节变化趋势为 8月 >9月 >4月 >5月 >11月。在低肥力土壤上 ,单独施用化肥与对照相比可以增加蚯蚓的数量 ,施用化肥对蚯蚓的影响程度依赖于有机物的投入情况 ,没有有机物投入或只有麦秸还田条件下 ,施用化肥会对土壤中蚯蚓的种群数量产生负面影响 ,随着时间的延长 ,这种影响表现得比较明显。在同时用玉米秸和麦秸还田的情况下 ,施用化肥对蚯蚓的种群数量影响较小。有机肥的施入可以增加蚯蚓的种群数量 ,随着时间的延长这种趋势愈为明显。在几种秸秆还田的投入方式中 ,蚯蚓种群数量的大小次序为双倍麦还 >玉米麦秸全还 >麦还。因此在施用化肥的时候应当同时进行有机物投入 ,以保持土壤中良好的生物状况 ,这也是土壤培肥的重要环节。 相似文献
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目的:利用3种方法对新城疫(Newcastle disease virus, NDV)病毒进行检测并对这3种检测方法的优缺点做出比较。方法:分别将NDV强毒F48E9和弱毒Lasota接种SPF鸡胚后,获取尿囊液。利用双抗夹心ELISA法、悬液芯片系统以及RT-PCR进行检测。通过对制备的针对新城疫病毒的抗体4D9和6C4蛋白浓度测定后,选择6C4进行生物素标记,将4D9作为固相捕获抗体,利用生物素-链霉亲和素放大系统构建双抗夹心检测体系。通过对Genebank上已发表的新城疫强弱毒F基因进行电脑分析后,设计一组针对NDV强弱毒的通用型引物,分别对强弱毒进行RT-PCR并检测其检出限。结果:ELISA法对NDV强弱毒尿囊液的检出灵敏度为1:160,但操作繁琐,耗时长;液相芯片对强弱毒尿囊液的检出限为1:160和1:320,然而和ELISA相比,操作较为方便,但仪器设备昂贵。RT-PCR对强弱毒RNA检出限分别为259pg和14pg,与前两种方法相比,PR-PCR在核酸水平上对病毒进行检测,理论上灵敏度较高,但是所需试剂、设备昂贵,且实验人员还需一定的技能培训。 相似文献
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本研究采用闪式提取技术,固液比为1:4(m/V)的2.5 mmol/L pH 7.0磷酸缓冲液,提取转速5500 rpm,提取时间2 min,从蚯蚓体内提取出SOD、CAT,并通过羧甲基纤维素CM-22离子交换层析实现SOD和CAT的联合提取分离,SOD、CAT的活性回收率分别达到88.23%和69.5%。在纯化工艺中经过丙酮沉淀和柱层析技术得到蚯蚓SOD纯品,比活达到9352 U/mg,产物在SDS-PAGE上为单一条带,其亚基分子量约为17 kD;通过柱层析纯化了蚯蚓CAT,比活达到22606 U/mg。 相似文献
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Eight novel polymorphic microsatellite loci are presented for garlic mustard (Alliaria petiolata, Brassicaceae) a European herb that is a serious invader of North American deciduous forests. The microsatellites will be useful tools to analyse pathways of introduction of garlic mustard, as well as its evolutionary potential in the invasive range. 相似文献
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Wang Linghong 《人类学学报》1986,5(03):243
China is rich in Neolithie human skeletons as well as Paleolithic human remains. The former is even more abundant in number. Nevertheless, the evolutionary aspeets of these skeletons and their morphological differences from modern ones have not drawn sufficient attention. The present paper aims to examine the nature of morphologieal evolution in Holocene human populations of China. In literature were described about 20 Chinese Neolithie sites yielding more or less human crania, at most 30—40, at least 1—2. Among them, southern and northen populations were separated, and the North China group was further subdivided into eastern and western subgroups.<br>In order to involve as many groups and variables as possible, two techniques were used for preparing the data-sets. These are 1)combination of sample groups and 2) estimation of missing values.<br>There are two reasons for eombining sample groups. First of all, in some cases, there were more than one group sampled from the same population. Usually, one can not know which is more representative. Combining them is a better way than choosing at random, as long as there exists reasonable similarity among the samples. Secondly, combining is useful when any sample group does not contain sufficient number of samples, or has all variables represented. The member groups can be mutually complementary.<br>In this study, after combining samples there were still some missing values in the data-sets. And these missing values involved such important groups as the Zengpiyan group and such important variables as eranial base length and facial length. In order to maintain both these groups and these variables in the statistical study, the missing values had to be estimated. Stepwise regression analysis was used for that. The estimated values have been proved reliable by both the F-test and the correlation test.<br>Cluster analysis, factor analysis, diseriminant analysis and two way variance analysis were used in this study. The results produced by these four techniques are quite consistent.<br>1. Cluster analysisIn the dendrogram of the male groups based on Penrose's shape distances, Neolithic north and south groups, and modern north and south groups respectively form their own blocks. One exception is the Gansu-Henan Neolithie group, which was excavated by the Swedish geologist and archaeologist J. Andersson and studied by the Canadian anthropologist D. Blaek. The two regional branehes of the same period join with each other respeetively. Then, the Neolithie branch and the modern branch link at a higher level (greater distance) . This shows that there is a bigger difference in terms of time than of region. In other words, the secular change is generally more significant than the geographical variation. In addition, in the Neolithic branch and the modern branch, the artificially deformed groups are specially separated as expeeted.<br>2. Factor analyssIn the factor analyses of both the male and the female groups, almost all of the linear variables have large positive loadings for thefirst factor, especially facial length, bizygomatie breadth, eranial base length, basi-bregmatie height, minimum frontal breadth and nasal breadth. The first factor, therefore, can be called the size factor.<br> For the second factor, upper facial height and nasal height have large loadings. This is the facial height factor.<br>The coordinates of the first two factors marking the positions of the groups studied produced the same results as shown above. The two axes distinguish temporal and regional groups respectively. The first factor (X-axis) distinguishes between Neolithic and modern populations. The second factor (Y-axis) distinguishes between north and south populations. Once again, the Gansu-Henan Neolithie group is the only exception.<br>The aceuracy of the ehronology for at least some of the samples of the Gansu-Henan group has been questioned based on a review of the Neolithie cultural context. The above analyses support this doubt.<br>To compare the male and the female Hemudu specimens is also interesting. Each is represented by only one sample. The male sample (M23 is bigger than the other male groups on the average, while the female one (M 17) is smaller than the other female groups. It is not likely that the tremendous differences of these two samples reflect a extremely big sexual dimorphism of the population. They seem to be merely extreme samples in their respective sexes.<br>It is not proper to include the Gansu-Henan group and the Hemudu specimens in the further analyses.<br>3. Discriminant analysisThe purpose of the discriminant analyses is to detect the significance of the difference between the temporal groups (i. e. Neolithic and modern group) or the regional groups (i. e. north and south group) in each variables. The analyses of the male groups obtained exactly the same results as did the faotor analysis: there were very significant temporal differences in eranial base length, facial length, basi-bregmatie height, nasal breadth, bizygomatic breadth and minimum frontal breadth and very significant or significant regional differences in nasal height and upper facial height.<br>4. Two way variance analysisThe time sequence consists of early Neolithic, late Neolithie and recent times. The region sequence consists of northern, central-eastern and southern China. 9 male groups were chosen to fill in the tablet of the two sequences. The analyses of 8 variables show somewhat gradual changes over time in basi-bregmatic height, nasal breadth, minimum frontal breadth, eranial length and bizygomatic breadth, and somewhat gradual changes over region in upper facial height, nasal height and eranial length.<br>Orbital dimensions were not included in the above analyses, because it was noticed that significant errors had been made in measuring orbital height and breadth, and because not all groups contained the mean values of these two measurements. To test whether these two variables are still useful in further discussion, another seattergram was drawn with two axes representing orbital height and orbital breadth respectively. It is shown that there exist differences among the four bloeks: the Neolithic groups have wider and lower orbitals than the modern ones, while the northern groups have higher orbitals than the southern ones. This indieates that errors of measurement of the orbital dimensions do not affeet comparative study to sueh an extent as to obseure the differences in question over time and region.<br>Based on the above analyses, the secular change and the geographical variation in question can be summarized as follows.<br>Chinese Neolithic residents had larger erania than the modern population. This was reflected in cranial base length, facial length, eranial height, nasal breadth, bizygomatic breadth, minimum frontal breadth and orbital breadth. Their upper facial height and orbital height were slightly lower than in the modern population.<br>As to geographical variation, in both Neolithic and recent times northern Chinese inhabitants have higher upper facial height, orbital height and nasal height than southern Chinese ones.<br>Generally speaking, the seeular ehange is more significant than the geographical variation.<br>The present study is an attempt to consider seeular change and geographical variation at the same time. Obviously, this is often necessary. For instance, sereral Neolithic groups of Shaanxi Yang-shao Culture were characterized by relatively low facial height and relatively prominent prognathism ete. At first sight, they seemed to represent anomalous geographical variation. Taking secular change into account, however, one finds a somewhat inereasing tendency toward facial height and a somewhat decreasing tendeney to prognathism. Therefore, it is not reasonable to regard this Neolithic population as a separate variant of the southern Mongoloid racial stock. The statistical analyses illustrate that to study these two aspects of changes of populations at the same time is not only necessary but also possible if only these changes happened in different eharacters.<br>The statistical analyses were carried out under the instruction of Prof. Kazuro Hanihara during the author's stay in the University of Tokyo as visiting scholar. Gratitude is expressed to him and his colleagues, especially Dr. Makiko Kouchi and Mr. Kiyotaka Koizumi for their help. Thanks are also due to Prof. Wu Rukang for his encouragement throughout this study. 相似文献
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中国新石器时代和现代居民的时代变化和地理变异——颅骨测量性状的统计分析研究 总被引：4，自引：4，他引：4
本文研究了中国新石器时代到现代人类颅骨主要测量性状的时代变化,以及这两个时代中的地理变异。聚类分析、因子分析、判别分析和方差分析的结果显示在此期间的时代变化顺着变小的趋势;在新石器时代和现代,北方居民比南方居民有更大的上面高、鼻高和眶高。北方和南方两支居民沿着共同的方向变化,同时保持原有的地理差异,这种平行现象为探讨此期间时代变化的动力可能提供一部分线索。 相似文献
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Joshua D. Webster Margaret A. Miller Dee DuSold Jos�� Ramos-Vara 《The journal of histochemistry and cytochemistry》2009,57(8):753-761
Immunohistochemistry (IHC) is routinely used in diagnostic pathology to detect infectious agents, to immunophenotype neoplastic cells, and to prognosticate neoplastic diseases. Formalin fixation is considered a limiting factor for IHC because formalin can cross-link antigens and mask epitopes. Prolonged formalin fixation is presumed to result in decreased antigen detection; however, this effect has only been evaluated with a few antibodies. The goal of this study was to evaluate the effect of prolonged formalin fixation on the immunohistochemical detection of 61 different antigens. Approximately 5-mm-thick tissue slices were fixed in 10% neutral-buffered formalin. Tissue slices were removed from formalin, processed, and paraffin-embedded at 1-day, 3-day, and then at ∼1-week intervals. IHC was performed on all sections in tandem after all tissues were processed. Immunoreactions were evaluated by three pathologists according to a four-tier grading system. Immunoreactivity of cytokeratin 7, high-molecular-weight cytokeratin, and laminin was diminished by prolonged formalin fixation. However, immunohistochemical reactivity remained moderate to strong with up to 7 weeks of fixation for all other antibodies. These results suggest that prolonged formalin fixation has minimal effects on antigen detection for most commonly used antibodies. These results further validate the use of IHC in diagnostic pathology. (J Histochem Cytochem 57:753–761, 2009) 相似文献
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Amynthas aspergillum (Perrier, 1872), a natural resource used in traditional Chinese medicine (Guang-dilong) with high economic value, is widely distributed in forests and farmland habitats in the hilly areas of southern China. To investigate the extent of genetic differentiation and diversity in A. aspergillum, a population genetic structure study was performed on 157 samples from 75 locations in southern China using the mitochondrial genes COI, COII, 12S rRNA, 16S rRNA, and NDI. The results indicated that A. aspergillum had a high level of genetic diversity, and variation within populations was the main source of the total variation. Six deeply divergent mitochondrial clades (I–VI) were detected using both phylogenetic tree and haplotype network analyses. This finding was supported by the high Kimura two-parameter genetic distance and the pairwise fixation index value obtained based on the COI gene. No significant phylogeographic structures were observed. The widespread geographic distribution of clades II, IV, and VI suggested a recent demographic expansion based on multiple analysis results. These results include a high level of Hd and low π, star-shaped haplotype network structures with a high number of less frequent haplotypes, significantly negative neutrality test values, and a unimodal mismatch distribution pattern. The divergence time estimates and reconstruction of the ancestral area revealed that A. aspergillum originated in Guangxi Province and underwent initial intraspecific diversification in the early Pliocene to generate clade I. Then, it gradually dispersed eastward and rapidly differentiated into clades II–V during the Pleistocene. The Yunnan-Guizhou Plateau and Nanling and Wuyi Mountains might act as geographical barriers for the spread of A. aspergillum to the west and north. 相似文献
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为有效利用叶用芥菜种质资源,对筛选出的24份叶用芥菜品系资源的11个表型性状,应用相关系数、聚类分析和主成分分析等多元统计方法进行遗传多样性分析。结果表明:叶用芥菜种质资源具有丰富的遗传多样性;11个表型性状平均变异系数为44.74%,叶片数的变异系数最大,为150.80%;净菜率变异系数最小,仅为9.54%。通过系统聚类,将参试的24份品系分为3个类群,第Ⅰ类群有14份材料,第Ⅱ类群有5份材料,第Ⅲ类群有5份材料,各类群性状之间的差异较明显,明确了品系类群间存在的亲缘关系。在主成分分析中,可选取方差累计贡献率为86.62%的前5个主成分来评价24份叶用芥菜品系资源。本研究揭示了叶用芥菜不同品系的表型特异性和遗传多样性,筛选出一些特异品系资源,为高产优质叶用芥菜新品种(系)的选育提供重要的科学依据。 相似文献
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R.P. Dales 《Journal of invertebrate pathology》1978,32(3):264-277
Body wall grafts have been exchanged between Lumbricus terrestris and Eisenia foetida unicolor, and the survival times of second-set grafts and a limited number of third-set grafts have been compared with those of first-set grafts. Survival of grafts has also been studied following implantation. The results do not support the hypothesis that second-set rejection is accelerated due to an immune response as in higher vertebrates. Evidence is presented that Eisenia are individually different and that the differential graft survival may be due to tissue incompatibility, survival times depending on the degree of difference in the environment presented by the recipient. 相似文献
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G. Floris M. G. Franceschi G. Paoli E. Sanna L. Taglioli 《International Journal of Anthropology》1998,13(1):57-64
We describe the genetic structure of twenty Sardinian subpopulations using quantitative palmar dermatoglyphic traits (a-b, and A-d counts, atd angle value, coefficient of Turpin and Lejeune, main line index, mean of A-, B-, C, and D-line terminations) of 3777 subjects (2043 males and 1734 females). The twenty subdivisions represent sixteen historical-geographic areas of the island in which people speaks Sardinian language, Sassarese and Gallura areas in which people speaks two Italian dialects, and the two communities of Alghero (Catalan speaking) and Carloforte (Ligurian speaking). Analysis was carried out for both hands and both sexes combined and using R-matrix technique and the extension of the Harpending-Ward model to quantitative traits according to Relethford & Blangero (1990). Multivariate minimum Fst value (0.0127) is higher than that of most. Mediterranean populations and shows the importance of isolation and genetic drift as evolutive forces at the basis of microdifferentiation among the Sardinian subpopulations considered. However, when the four populations not speaking Sardinian language are removed from the analysis, the value of Fst decreases to 0.008. The regression of mean genetic variance on distances from the centroid (rii values) states the marked effect of the genetic drift for Nuorese and Barbagia di Ollolai subdivisions (placed in the inner and mountainous areas of Sardinia) and reveals considerable levels of admixture for Carloforte subdivision. The contemporary genetic structure of these groups reflects their historical, linguistic and geographic characteristics. On the whole, our analysis confirms the usefulness of quantitative dermatoglyphic traits in studying genetic population structure. 相似文献
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In India, molecular mapping and tagging of agronomically important genes using RFLP and RAPD markers have been carried out in three different crops: rice, mustard and chickpea. In rice, tagging of genes for resistance to gall midge and blast has been accomplished. Molecular mapping of cooking quality traits in rice is in progress. For fingerpringting rice cultivars, suitable probe enzyme combinations have been identified. In mustard, a partial RFLP linkage map has been constructed and one of the yellow seed-coat colour loci has been mapped. Significant associations of RFLP markers with quantitative traits have also been established. Potential use of RAPD markers to identify heterotic groups among mustard accessions has been demonstrated. In chickpea, the occurrence of considerable interspecific DNA polymorphism as revealed by RAPD analysis has facilitated construction of a partial linkage map. 相似文献