The intertidal soft-bottom infaunal macrobenthos in three Basque estuaries (Gulf of Biscay): a feeding guild approach

Feeding types of the infaunal macrobenthos of the intertidal soft-bottom communities from the estuaries of La Arena, Plentzia and Gernika, along the Basque coast (Gulf of Biscay) were studied in relation to habitat conditions, characteristics of each estuary and seasonal variation. General feeding structure observed in La Arena estuary was different from the other estuaries: omnivores were dominant, both in number of species and individuals, while surface deposit-feeders were the main feeding group in Plentzia and Gernika both in the finest sediment communities and in the sandy ones. Subsurface deposit-feeders were abundant in Plentzia and Gernika but scarce in La Arena estuary. Feeding types were related to the environmental variables. Sandy sediment communities presented a more balanced proportion among different feeding types and showed higher values of feeding diversity; suspension-feeders and predators were abundant only in that communities. By estuaries, feeding diversity was higher in Gernika and lower in La Arena. Seasonal variation in feeding diversity was observed, explained by changes in density of certain feeding groups; a common pattern of variation was found in Gernika communities, with an increase in June and a decrease in September. Oscillation of this index in Plentzia and La Arena depended on the estuary and the different communities; nevertheless a decrease of feeding diversity in September was commonly observed. Finally, feeding structure observed in our estuaries was compared to those described in coastal areas with organic enriched sediments, in order to assess the degree of perturbation of the environment based on the relative dominance of a certain feeding type in the macrobenthos.     

Abundance estimation of rocky shore invertebrates at small spatial scale by high-resolution digital photography and digital image analysis

We have tested both the usefulness of high-resolution digital photography for data acquisition and digital image analysis, by non-supervised classification and high pass filter, for recognition and abundance estimation of benthic intertidal organisms. These digital tools were compared with visual scan and photo quadrat conventional methods. The comparison was done using 40 quadrats (10×5 cm) randomly selected along a 5-m transect on the rocky shore of the Pemaquid Point, Maine, USA. ANOVA for repeated measures was used to test differences among methods. Monte Carlo simulation analysis was used to explore differences among methods over a large set of data (n=100, 500, 1000 quadrats). Differences among methods were observed when 40 quadrats were used. Tukey multiple comparison test showed that abundance estimation from visual scan, photo quadrat and digital image analysis by high pass filter do not differ significantly among them but differ from non-supervised classification results. Due to its accurate estimation, high pass filter (Prewitt) method was chosen as the most reliable digital method to estimate species abundance. Monte Carlo simulation of visual scan, photo quadrat and high pass filter results showed significant differences when the number of quadrats was larger. These results showed that the combined use of digital photography and digital image analysis techniques for the acquisition and analysis of recorded data is a powerful method for the study of intertidal benthic organisms. Results produced using these techniques were similar than those produced by conventional methods but were obtained in a much-reduced time.     

马尾松毛虫灾变发生类型与地貌及植被特征间对应分析

1　引　　言对应分析 (ｃｏｒｒｅｓｐｏｎｄｅｎｃｅａｎａｌｙｓｉｓ)由法国Ｂｅｎｚｅｃｒｉ于1970年首先提出 ,是在Ｒ型和Ｑ型因子分析基础上发展起来的一种多元分析方法[5] .它与主成分分析有着密切的联系 ,在某种意义上可以看成是主成分的特殊情形 ,从另外一种意义上讲 ,它又是主成分分析的推广 .另外 ,它和典型分析也是相通的[4 ] .对应分析的主要目的是寻求列联表行因素和列因素的基本分布特征和最优联立表示 ,并将彼此间的结构关系直观地展示出来 .对应分析已被用于生物学研究的不同领域[2 ,3 ] .本文应用对应分析方法 ,对小班 (ｓ…     

对应分析在水稻区域试验中的应用初步

应用对应分析对1996年全国籼型杂交稻区域试验中稻两系组和三系组的产量资料进行分析,结果表明：当存在显著的基因型与环境互作时,对应分析用于参试品种的稳定性,所得结果与AMMI模型分析的结果一致,结果聚类分析,能进一步揭示基因型与环境之间真实的结构关系。     

Parallelism between the frequencies of differently oriented whorls and other pattern types in Basque population

In a sample from the Biscaian Basque population, we studied the incidence of pattern types in fingers and the parallelism between the frequencies for the orientations of whorls (Wr, Ws, Wu) and the other pattern types (Lr, A, Lu). We reaffirm the importance of clarifying pattern types according to their orientation, which is of general use in the case of loops but less easily applied to whorls.     

Geographical variation of digital dermatoglyphics in Africa

Data from 142 male and 43 female samples of African populations have been used to analyze the geographical variation of digital dermatoglyphics (arches, loops, whorls, and pattern intensity index) in Africa. The patterns of geographical variation have been summarized as contours of sixth-degree polynomial surfaces by means of trend-surface analysis. As pointed out by early studies, Africa exhibits geographical clines of digital dermatoglyphic patterns. However, only some of the frequency gradients previously described for the region find confirmation in the present study.     

逐步对应分析及中国少数民族人群体态特征研究

介绍了逐步对应分析方法,给出了变量选择和误差估计的标准,并分析了中国26个少数民族人群体态特征。     

Correlation between soil characters and forest types: a study in multiple discriminant analysis

Multiple discriminant analysis is a useful multivariate technique in vegetation studies that can be employed for several purposes, even if the underlying statistical assumptions are not satisfied. An example of application of this method is discussed: multiple discriminant analysis was successfully used for evaluating the predictivity of forest types defined by numerical classification of vegetation data with respect to soil variables.Species nomenclature follows Pignatti (1982) for vascular plants and Augier (1966) for mosses.The research has been supported by the IDROSER (Bologna, Italy) and by the Italian C. N. R. (Grant no. 83.02548.04, resp. Prof. A. Pirola). We wish to thank Prof. E. Feoli, Prof. E. van der Maarel, Prof. L. Orlóci and Prof. A. Pirola for suggestions. We are also indebted to Dr N. Filippi who analyzed the soil samples.     

Quantitation of types I and III collagens in human tissue samples and cell culture by cyanogen bromide peptide analysis

A procedure for the quantitation of types I and III collagens by cyanogen bromide peptide analysis was developed with the aim of eliminating certain problems associated with this method. Ion-exchange chromatography reduced high background levels on gel scans used to quantitate the peptides; reduction with beta-mercaptoethanol substantially increased the efficiency of the cyanogen bromide cleavage; use of a concave gradient in acrylamide from 8 to 20% improved the resolution of cyanogen bromide peptides separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis; and a normalization procedure eliminated variations due to differences in the amount of material loaded on the gel system. This method of quantitation was applied to human aorta samples and to collagen secreted by human skin fibroblasts. Metachromasy of type I and type III collagen cyanogen bromide peptides stained with Coomassie blue R-250 was established and this was used as an index of the purity of the cyanogen bromide peptide preparations. Type I and III collagens were prepared from human placental tissue, and these purified collagens were used to construct calibration curves to determine the relationship between the quantity of diagnostic cyanogen bromide peptides present and the composition of the sample in terms of types I and III collagens.     

Analysis of codon usage pattern in the radioresistant bacterium Deinococcus radiodurans

The main factors shaping codon usage bias in the Deinococcus radiodurans genome were reported. Correspondence analysis (COA) was carried out to analyze synonymous codon usage bias. The results showed that the main trend was strongly correlated with gene expression level assessed by the "Codon Adaptation Index" (CAI) values, a result that was confirmed by the distribution of genes along the first axis. The results of correlation analysis, variance analysis and neutrality plot indicated that gene nucleotide composition was clearly contributed to codon bias. CDS length was also key factor in dictating codon usage variation. A general tendency of more biased codon usage of genes with longer CDS length to higher expression level was found. Further, the hydrophobicity of each protein also played a role in shaping codon usage in this organism, which could be confirmed by the significant correlation between the positions of genes placed on the first axis and the hydrophobicity values (r=-0.100, P<0.01). In summary, gene expression level played a crucial role, nucleotide mutational bias, CDS length and the hydrophobicity of each protein just in a minor way in shaping the codon usage pattern of D. radiodurans. Notably, 19 codons firstly defined as "optimal codons" may provide useful clues for molecular genetic engineering and evolutionary studying.     

A note on the occasional instability of detrending in correspondence analysis

When the two first eigenvalues of correspondence analysis are close to each other, their order can be reversed due to random variation in the data. The first axis can actually be in any direction in the plane defined by the two axes. However, the configuration of the points in the plane can remain unchanged but their projections onto any line in the plane can be very variable. The ordering in the first axis is preserved in detrending. The second axis is detrended with respect to the first one and therefore very variable configurations result when the orientation of the first axis in the plane is changed. This can lead to a situation where the detrended solutions are very unstable under random variation and therefore they can be only casually interpretable.     

青岛崂山茶区土壤生境因子对应分析

通过对崂山茶区土壤生境因子与不同茶园进行对应分析研究,发现可以按照崂山茶区土壤特征将不同的茶园分成三类:富磷区、富有机质区、老茶园区.从而为崂山茶区不同种类茶树种植以及如何改良土壤促进茶树生长提供依据.     

Using digital image analysis to quantify the architectural parameters of roots grown in thin rhizotrons

Abstract

Roots grown in small chambers or rhizotrons combined with image analysis could be effective for screening traits of root morphology and architecture prior to field experimentation. The objective of this study was to evaluate and compare digital images of root systems with conventional root scans (RSCN) for several sorghum varieties grown in rhizotrons. Plants were grown in duplicate in slim (1.5‐cm thick) rhizotrons angled 15° to the vertical, filled with sandy topsoil and subsoil at field capacity (FC) or 50% available water content (AWC) in a split‐plot design in a glasshouse (16/24°C). Root growth visible on the glass surface was recorded weekly, and roots were washed out 42 and 90 days after sowing for digital imaging of the root systems on pin boards (PBI). The roots were then sub‐sampled to quantify the baseline root parameters from digital RSCN using WinRhizo® software with a flat‐bed scanner. Rhizotron images revealed little of the root system (1–2%) but PBI “recovered” up to 70% of the total root length (TRL) measured by RSCN. A high a priori image contrast, increased image resolution (9.1–12 megapixels) and optimized contrast threshold between roots and background were the key parameters in quantifying the roots from digital images. PBI revealed significant differences in rooting patterns, especially distribution of root length density (RLD) in the profile, which is useful for selecting varieties with improved resource capture. However, the root diameters estimated in the PBI were significantly larger than those measured by RSCN due to lack of contrast, root clustering and overlay.     

Correspondence analysis of functional groups in a riparian landscape

We used multivariate analysis and ordinations to characterize thecomposition and distribution of woody vegetation within the Ozark NationalScenic Riverways (ONSR), Missouri, USA. The objectives of the study were to: 1)evaluate patterns of woody species distributions along existing environmentalgradients; 2) determine if different classes of woody plants (i.e., dominantoverstory trees, all trees, understory trees, and shrubs) responded similarlytothe same suite of environmental variables; and 3) determine if discreteecotonaland/or ecoclinal vegetation patterns were present across the landscape. Woodyvegetation was sampled from 94 plots along 35 transects positioned at rightangles to the river channel. Sample plots were analyzed with DetrendedCorrespondence Analysis (DCA), Canonical Correspondence Analysis (CCA), andTWINSPAN. Overall, woody vegetation was correlated with several environmentalgradients, including elevation of the plot above the river, soil pH, soilmoisture, and soil particle size. Responses to secondary gradients differedamong the four classes of plants analyzed, however. CCA biplots of understorytrees indicated that patterns of those species were strongly correlated withslope through the plot and sand content of soil. CCA biplots of shrubs showedthat CCA axes were most strongly correlated with soil organic matter content,soil moisture, and silt content. Further, there was limited evidence fordiscrete assemblages of woody species, with the exception of streamsidevegetation. Instead, mixing of woody species was observed across a broadtransition zone. Because there is little correspondence between vegetationlayers, our results demonstrate including plant classes other than a subset ofcanopy dominant trees can provide additional resolution in characterizingvegetation responses along complex environmental gradients.     

Helminth parasites of the Eurasian badger (<Emphasis Type="Italic">Meles meles</Emphasis> L.) in the Basque Country (Spain)

The helminthological study of 26 Eurasian badgers (Meles meles L.) in the Basque Country (northern Spain) revealed the presence of two trematode (Euryhelmis squamula and Brachylaima sp.), three cestode (Atriotaenia incisa, Mesocestoides sp. and Taenia sp.) and five nematode (Aonchotheca putorii, Physaloptera sp., Molineus patens, Uncinaria criniformis and Strongyloides sp.) species. All 15 individuals analysed for Trichinella sp. were negative. The coprological analysis (flotation and migration) revealed the excretion of strongylid, capillariid and trematode eggs, and Crenosoma sp. and Angiostrongylus sp. larvae. No sex- or age-related differences were found in the parasite burden or egg and larvae excretion. A. incisa and M. patens abundances were positively correlated, both species being negatively correlated with badger weight. The presence of adults of U. criniformis and strongylid eggs in faeces was not independent. Badgers excreting Angiostrongylus larvae were in poorer condition than those not excreting.     

Cranial variation in the Iberian Peninsula and the Balearic Islands: Inferences about the history of the population

A multivariate analysis of four prehistoric and nine historic populations from the Iberian Peninsula and Balearic Islands with large sample sizes (n > 30 individuals for the neurocranium and n > 15 for the facial skeleton) is presented, considering 874 male and 557 female skulls and using 20 craniometric measurements. Cluster analyses have been undertaken using the squared Euclidean distance as a measure of proximity and the average linkage between groups (UPGMA), and neighbor-joining algorithms as a branching method, and a bootstrap analysis was used to assess the robustness of the clustering topology. The study was complemented with a principal coordinate analysis and with the application of the Mantel test to measure the degree of correspondence between the information furnished by the female and the male samples. The analyses show that the main source of morphometric variability in the Iberian Peninsula is the Basque population. The second source of variation is provided by two populations (Muslims and Jews), different from the rest from an archaeological and cultural point of view, and can probably be attributed to influences from sub-Saharan Africa. The massive deportations of the Jews in 1492 and of the Moors between the 15th and 17th centuries may have erased this source of variability from the present population of the Iberian Peninsula. The remaining studied populations, including samples from Castile, Cantabria, Andalusia, Catalonia and Balearic Islands, are grouped together, showing a notable morphological homogeneity, despite their temporal and geographic heterogeneity. These results are in general agreement with those obtained in synthetic maps, by analyzing multiple genetic markers. In such studies, the Basque population is described as the main source of genetic variability, not only in the Iberian Peninsula, but also in Western Europe. © 1996 Wiley-Liss, Inc.