Correlation between species composition and soil properties in the pastures of Plana de Vic (Catalonia, Spain)

The correlation between the species composition of pasture communities and soil properties in Plana de Vic has been studied using two multivariate methods, Correspondence Analysis (CA) for the vegetation data and Principal Component Analysis (PCA) for the soil data. To analyse the pastures, we took 144 vegetation relevés (comprising 201 species) that have been classified into 10 phytocoenological communities elsewhere. Most of these communities are almost entirely built up by perennials, ranging from xerophilous, clearly Mediterranean, to mesophilous, related to medium-European pastures, but a few occurring in shallow soils are dominated by therophytes. As for the soil properties, we analysed texture, pH, depth, bulk density, organic matter, C/N ratio and the carbonates content of 25 samples, correspondingto representative relevés of the communities studied.

Aspectes metodològics i técnica d'analisi en l'estudi dels grups i les classes socials

En aquest article es presenta el procés metodològic, com també les tècniques d'anàlisi de dades, que s'ha utilitzat en l'anàisi dels grups socials mitjançant la informació d'una gran enquesta sobre hàbits i condicions de vida. L'anàlisi dels grups socials des d'una perspectiva globalitzadora i estructuradora de les condicions de vida, tenint en compte com aquests sorgeixen mitjançant I 'associació i la coherència entre múltiples característiques. Les tècniques d'anàlisi de dades que s'han utilitzat han estat l'anàlisi de correspondències múltiples i l'anàlisi de classificació.

La construcció de tipologies: progrés i analisi de les dades

Aquest article recull un mateix procés metodològic en el qual s'emmarquen diverses investigacions presentades en aquest volum de la revista, amb un mateix objectiu: la construcció de tipologies en diferents àmbits temàtics. L'article especifica el marc general del disseny, descriu el seu procés metodològic i d'anàlisi de dades que pot caracteritzar-se per: (1) La font de dades prové d'una gran enquesta sobre hàbits i condicions de vida de la població, l'Enquesta Metropolitana de Barcelona 1990. (2) El plantejament d'un objecte d'estudi concret dins d'una realitat multivariable. (3) La utilització de tecniques d'anàlisi multivariables, en concret,l'Anàlisi de Correspondències Múltiples i les Tècniques de Classificació Automàtica.

Genetic variability of Brazilian rice landraces determined by SSR markers

The objective of this study was to evaluate the genetic variability of rice (Oryza sativa) landraces collected in Brazilian small farms. Twelve simple sequence repeat (SSR) markers characterized 417 landraces collected in 1986, 1987 and 2003, in the state of Goiás, Brazil. The number of landraces with long and thin grain type increased in the evaluated period, probably due to market demand. Based on the molecular data, the genetic variability increased during this period and, as per to the factorial correspondence analysis, most of the accessions were grouped according to the year of collection. The incorporation of modern rice cultivars in landrace cultivation areas and the selection carried out by small farmers are the most probable factors responsible for increasing landrace genetic variability, during the evaluated period. Genotype exchange between farmers, selection practice and local environmental adaptation are able to generate novel adapted allele combinations, which can be used by breeding programs, to reinitiate the process.

Diversity of springtails (Hexapoda) according to a altitudinal gradient

The objective of this work was to elevate gradient effect on diversity of Collembola, in a temperate forest on the northeast slope of Iztaccíhuatl Volcano, Mexico. Four expeditions were organized from November 2003 to August 2004, at four altitudes (2,753, 3,015, 3,250 and 3,687 m a.s.l.). In each site, air temperature, CO2 concentration, humidity, and terrain inclination were measured. The influence of abiotic factors on faunal composition was evaluated, at the four collecting sites, with canonical correspondence analyses (CCA). A total of 24,028 specimens were obtained, representing 12 families, 44 genera and 76 species. Mesaphorura phlorae, Proisotoma ca. tenella and Parisotoma ca. notabilis were the most abundant species. The highest diversity and evenness were recorded at 3,250 m (H' = 2.85; J' = 0.73). Canonical analyses axes 1 and 2 of the CCA explained 67.4% of the variance in species composition, with CO2 and altitude best explaining axis 1, while slope and humidity were better correlated to axis 2. The results showed that CO2 is an important factor to explain Collembola species assemblage, together with slope and humidity.

Structure of Poduromorpha (Collembola) communities in "restinga" environments in Brazil

The objectives of this work were to evaluate the richness and diversity of the Poduromorpha fauna in two biotopes in Restinga de Maricá, RJ, Brazil, to identify the characteristic species of each biotope and to determine the relationships between the community structure and the abiotic environmental parameters. Representatives of the Poduromorpha (Collembola) order were studied under an ecological viewpoint in halophyte-psammophyte vegetation and foredune zone in preserved areas of Restinga de Maricá, a sand dune environment in the state of Rio de Janeiro, Brazil. The foredune zone showed the highest diversity, richness and equitability of springtail species. Differences in the fundamental, accessory and accidental species in each environment were encountered. Paraxenylla piloua was found to be an indicator species of the halophyte-psammophyte vegetation, while Friesea reducta, Pseudachorutes difficilis and Xenylla maritima were indicators of the foredune zone. The canonical correspondence analysis indicated pH, organic matter content and soil humidity as the most important factors influencing the spatiotemporal distribution of the species.

Selection of the most informative morphoagronomic descriptors for cassava germplasm

The objective of this work was to select the most informative morphoagronomic descriptors for cassava (Manihot esculenta) germplasm and to evaluate the ability of different methods to select the descriptors. Ninety-five accessions were characterized using 51 morphoagronomic descriptors. Data were subjected to a multiple correspondence analysis (MCA), whose information was used in the following four methods of descriptor selection: reverse order of the descriptor for the pth factorial axis of the MCA (Jolliffe); sequential, multiple correspondence analysis (SMCA); mean of the contribution orders of the descriptor in the first three factorial axes (C3PA); and C3PA method weighted by the respective eigenvalues of the full analysis (C3PAWeig). The correlations between the dissimilarity matrix with all descriptors and the most informative descriptors were high and significant (0.75, 0.77, 0.83, and 0.84 for C3PAWeig, C3PA, SMCA, and Jolliffe, respectively). The less informative descriptors were discarded, considering those common among the selection methods and relevant for the breeding interests. Therefore, 32 morphoagronomic descriptors with correlation between the dissimilarity matrices (r=0.81) were selected, due to their high capacity to discriminate cassava germplasm and to their ability to maintain some preliminary agronomic traits, useful for the initial characterization of the germplasm.

Factores de explotación asociados a la duración del anestro postparto en vacas nodrizas de razas Parda de Montaña y Pirenaica

Para determinar los factores de explotación relacionados con la reactivación ovárica postparto en vacas nodrizas se realizó un análisis global de una serie de indicadores productivos y la duración del anestro postparto (APP) de 549 vacas explotadas en condiciones extensivas. Debido a la naturaleza multifactorial del proceso en estudio se eligió la metodología estadística multivariante (Análisis Factorial de Correspondencias Múltiples y Análisis Cluster). La duración del APP estuvo asociada a cuatro factores que explicaron el 59% de la heterogeneidad inicial de la muestra y que se definieron como: «Alimentación preparto» (19% de la inercia), «Alimentación postparto-Edad» (16.4%), «Manejo del ternero» (13%) y «Dificultad al parto» (10.5%). Estos factores se introdujeron en un Análisis Cluster que identificó cinco grupos de vacas con características productivas y reproductivas diferentes, y que denominamos como: «Primíparas», «Acceso restringido», «Acceso Libre-Parda de Montaña», «Parto de otoño» y «Parto de primavera». La raza no estuvo relacionada con la duración del APP, aunque el análisis Cluster asoció los largos APP inducidos por la crianza libre con la raza Parda de Montaña. En la raza Parda de Montaña, la duración del APP fue mayor en primavera que en otoño debido a diferencias nutricionales más que a un efecto estacional en sí. El parto de otoño se adaptó mejor a las condiciones de montaña seca.

Vulnerability as a heuristic for interdisciplinary research: Assessing the thematic and methodological structure of empirical life-course studies

Changes in human lives are studied in psychology, sociology, and adjacent fields as outcomes of developmental processes, institutional regulations and policies, culturally and normatively structured life courses, or empirical accounts. However, such studies have used a wide range of complementary, but often divergent, concepts. This review has two aims. First, we report on the structure that has emerged from scientific life course research by focusing on abstracts from longitudinal and life course studies beginning with the year 2000. Second, we provide a sense of the disciplinary diversity of the field and assess the value of the concept of 'vulnerability' as a heuristic tool for studying human lives. Applying correspondence analysis to 10,632 scientific abstracts, we find a disciplinary divide between psychology and sociology, and observe indications of both similarities of-and differences between-studies, driven at least partly by the data and methods employed. We also find that vulnerability takes a central position in this scientific field, which leads us to suggest several reasons to see value in pursuing theory development for longitudinal and life course studies in this direction.

Macrofossils in Raraku Lake (Easter Island) integrated with sedimentary and geochemical records towards a palaeoecological synthesis for the last 34,000 years

Macrofossil analysis of a composite 19 m long sediment core from Rano Raraku Lake (Easter Island)was related to litho-sedimentary and geochemical features of the sediment. Strong stratigraphical patterns are shown by indirect gradient analyses of the data. The good correspondence between the stratigraphical patterns derived from macrofossil (Correspondence Analysis) and sedimentary and geochemical data (Principal Component Analysis) shows that macrofossil associations provide sound palaeolimnological information in conjunction with sedimentary data. The main taphonomic factors in fluencing the macrofossil assemblages are run-off from the catchment, the littoral plant belt, and the depositional environment within the basin. Five main stages during the last 34,000 calibrated years BP (cal yr BP) are characterised from the lithological, geochemical, and macrofossil data. From 34 to 14.6 cal kyr BP (last glacial period) the sediments were largely derived from the catchment, indicating a high energy lake environment with much erosion and run-off bringing abundant plant trichomes, lichens, and mosses into the centre of Raraku Lake.

Kuluttajien suhtautuminen aikakauslehden brändiin ja brändin persoonallisuuteen

Pro gradun tarkoituksena oli tutkia kuluttajien suhtautumista kolmen kuluttajille suunnatun aikakauslehden brändiin ja brändin persoonallisuuteen. Tutkimuksen kohteena olevat aikakauslehdet olivat naisille suunnattu, nuorille suunnattu sekä tekniikkaan keskittynyt aikakauslehti. Tässä tutkimuksessa käytettiin kvalitatiivista tutkimusmenetelmää. Sisällön erittelyn avulla tutkittiin eroja kuluttajien suhtautumisessa eri aikakauslehtibrändien ollessa kyseessä. Kuluttajien mielipiteitä aikakauslehtibrändin persoonallisuudesta selvitettiin aikakauslehtien verkkosivuilla olleen kyselytutkimuksen avulla, jonka tuloksia analysoitiin korrespondenssianalyysissä. Korrespondenssianalyysissä kvantifioitiin kvalitatiivista aineistoa. Aikakauslehtikustantajien mielipiteitä aikakauslehden brändistä tutkittiin aikakauslehtien verkkosivujen sisällön kautta. Kuluttajat näkivät aikakausilehtien brändeissä eri persoonallisuuksien piirteitä. Syyt kuluttajien suhtautumisessa eri aikakauslehtibrändeihin johtuvat pikemminkin eri kohderyhmistä kuin kustantajan rakentamista eroista. Kustantajien ja kuluttajien mielipiteet brändin persoonallisuudesta olivat naisille suunnatussa lehdessä hyvin yhtenevät, kun taas tekniikkaan suuntautunut lehti kärsi epäselvästä brändistä.

Zonation patterns of benthic communities in an upwelling area from de western Mediterranean (La Herradura, Alboran Sea)

Species composition and distribution of marine benthic communities from La Herradura (Alboran Sea, western Mediterranean) are described to characterise its rocky and sedimentary bottoms bionomically. Rocky bottoms were studied by means of several underwater transects and soft bottoms with fixed stations along a bathymetric gradient. The study of the floristic and faunistic composition of the rocky benthic communities highlights depth as the main axis of variation. Factorial Correspondence Analysis segregates deep-water communities below 25 m depth (circalittoral communities) from shallower communities (axis I), and communities thriving between 5 and 25 m depth (lower infralittoral communities) from communities thriving close to the surface (shallow infralittoral communities) (axis II). The study of the sedimentary bottoms also suggests that depth, together with physical sedimentary properties, is the main axis of variation in species distribution. Floristic and faunistic records show the particular composition of La Herradura benthic communities, compared to Mediterranean and Atlantic ones. Mixing of Mediterranean and Atlantic waters, together with deep water upwelling episodes typical of this area, probably determine the peculiar composition of the benthic communities

Dinámica del heleoplancton en relación a las fluctuaciones hidrológicas en aiguamolls de l’Empordà (NE de la península Ibérica). Propuesta de un método sencillo de monitorización basado en la abundancia de grupos taxonómicos

Monitoring of the 'ecological water quality' in 'Aiguamolls de l’Empordà' Natural Park was carried out between September 1996 and August 1997 . The aim of this sampling programme was to design a simple method for rapid detect changes in water quality due to human activity. These include flow regulation by the Park management, nutrient entries from effluents of a nearby wastewater treatment plant or agricultural fertilising. The proposed method is based on the analysis of the abundance of characteristic taxonomic groups of aquatic invertebrates (heleoplankton). The simplicity of the method is ensured by the use of large taxa which are easier to recognise than species. The functioning of aquatic systems has been modelled by means of correspondence analysis between samples and taxa. Results can be summerized in five environmental conditions with a regular community structure. Dominated by one taxon: cladocerans, ostracods, calanoids, cyclopoids and harpacticoids. The dynamics of both freshwater and brackish lagoons can be modelled as displacements between these five groups of environmental conditions. Nevertheless, the “calanoids situation” and the “harpacticoids situation” occur mainly in brackish lagoons, whereas the “cladocerans situation” occurs mainly in freshwater. The four principal axes of data variation have been respectively identified as nutrient turnover rate, hypertrophy, degree of mineralization of the organic matter and eutrophy. The use of these taxa has been validated by comparison with a model obtained from the species. We conclude that in a highly fluctuating system such as the one here, only persistent situations of eutrophy or hypertrophy must be equated to low 'ecological water quality'

Novel Regression Methods For Spectral Data

Singular Value Decomposition (SVD), Principal Component Analysis (PCA) and Multiple Linear Regression (MLR) are some of the mathematical pre- liminaries that are discussed prior to explaining PLS and PCR models. Both PLS and PCR are applied to real spectral data and their di erences and similarities are discussed in this thesis. The challenge lies in establishing the optimum number of components to be included in either of the models but this has been overcome by using various diagnostic tools suggested in this thesis. Correspondence analysis (CA) and PLS were applied to ecological data. The idea of CA was to correlate the macrophytes species and lakes. The di erences between PLS model for ecological data and PLS for spectral data are noted and explained in this thesis. i

Causes of death of thoroughbred racehorses at Octavio Dupont Veterinary Hospital, Brazilian Jockey Club, Rio de Janeiro

There are few studies that approach the epidemiology of deaths in racehorses in a broad manner. The majority focus on a specific affection or procedure. Brazil does not have a program instituted for the monitoring of deaths of horses. By means of a descriptive study in association with a multivariate analysis method, an epidemiologic profile was determined for deaths related to musculoskeletal (MS), gastrointestinal (GI), respiratory (RES) systems, neurologic origin (NEU) and sudden death (SD) for the years of 2002 to 2008, at the Octavio Dupont Veterinary Hospital-Rio de Janeiro (ODVH). Males comprised the majority of deaths and that deaths were related to, decreasing order, MS>GI>SD>NEU>RES, with respect to general mortality rate per large group of determined causes (TSPMr). The majority of deaths registered included horses aged four to five years (ID4-ID5). We observed the following correspondence relations: (3-year period = SM - ID>5 - SD; ID>5 - GI; ID4-5 - MS; SF - ID<4 - RES/ NEU); (4-year period = SM - ID>5 - GI; SF - ID<4 - NEU; ID4-5 - MS; GI - ID>5). The present study points out the importance and necessity of epidemiologic studies of lesions in horses, based on diagnosis for the recognition of predisposing factors and prevention.