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	Provedor de dados ArchiMer (3) Ciencia e Investigación Agraria (1) Acta Botanica (1) Scientia Agricola (1) Autor Petitgas, Pierre (2) Araujo,Dorothy Sue Dunn de (1) Authier, Matthieu (1) Bertrand, Jacques (1) Carrasco,Basilio (1) Chessel, Daniel (1) Doray, Mathieu (1) Dupuy, Christine (1) Díaz,Carole (1) Eaton,Lafayette (1) Fan,Jun (1) Gaertner, Jean-claude (1) Garbin,Mário Luís (1) García-Gonzáles,Rolando (1) Hu,Wei (1) Huret, Martin (1) Letelier,Luis (1) Nettesheim,Felipe Cito (1) Pereira,Marcos Gervasio (1) Petit, Didier (1) Mais... Palavra-chave Spatial structure (6) Acoustique (1) Analyse multitableaux (1) Assemblage de poissons (1) Bay of Biscay (1) Chalutage (1) Community composition (1) Community structure (1) Correspondence analysis (1) Disc infiltrometer (1) Echo surveys (1) Ecosystems (1) Fish assemblage (1) Fishing operation (1) Floristics (1) Genetic structure (1) Indonesia (1) Indonésie (1) Integrated surveys (1) Java Sea (1) Mais... Tipo do documento Text (3) Info:eu-repo/semantics/article (2) Journal article (1) Ano 2019 (1) 2018 (1) 2011 (1) 2008 (1) 1998 (1) 1997 (1) Mais... País France (3) Brazil (2) Chile (1) Idioma Inglês (6)		Ordenar por:  Relevância Autor Título Ano Registros recuperados: 6 Primeira ... 1 ... Última Stability of spatial structures of demersal assemblages: a multitable approach ArchiMer Gaertner, Jean-claude; Chessel, Daniel; Bertrand, Jacques. The present work is based on a set of bottom trawl surveys performed in the Gulf of Lions between 1983 and 1992. A new method which couples the STATIS multitable approach with the logic of correspondence analysis (CoA) is proposed to study the stability of spatial organization of demersal assemblages in terms of species composition. This CoA version of STATIS has provided a clear representation of the stable part of the spatial structure of the assemblages. In addition, it gave an insight into the interannual variations of the distribution of each population around the reference structure. Our results showed that the demersal assemblages of the Gulf of Lions exhibited strong spatial structuring, mainly orientated along a bathymetric gradient. This gradient... Tipo: Text Palavras-chave: Assemblage de poissons; Chalutage; Analyse multitableaux; Méditerranée; Stabilité; Structure spatiale; Fish assemblage; Trawl surveys; Multitable analysis; Correspondence analysis; Mediterranean sea; Stability; Spatial structure. Ano: 1998 URL: https://archimer.ifremer.fr/doc/1998/publication-875.pdf Interaction between fish and fishing vessels in the Javanese purse seine fishery ArchiMer Potier, Michel; Petitgas, Pierre; Petit, Didier. The purse-seiners of the Java Sea use light and fish aggregating devices (FAD) to concentrate and catch small pelagic fish (Decapterus sp., Amblygaster sirm, Sardinella gibbosa). This sets a question about the interaction between fish and fishing vessels. Relevant estimates of fishing mortality and fishing effort require an understanding of this interaction. To gain information on this relationship, acoustic surveys were performed on the fishing grounds and the present paper analyses these data. Using acoustic surveys, the fish density was measured and the number of schools was counted per sea surface unit. The fishing vessels were located by radar. Acoustic data were stratified into two groups, one where fishing vessels were present and the other where... Tipo: Text Palavras-chave: Pêche; Acoustique; Structures spatiales; Pélagiques; Mer de Java; Indonésie; Fishing operation; Echo surveys; Spatial structure; Pelagic fish; Java Sea; Indonesia. Ano: 1997 URL: http://archimer.ifremer.fr/doc/00188/29884/28343.pdf Ecosystem spatial structure revealed by integrated survey data ArchiMer Petitgas, Pierre; Huret, Martin; Dupuy, Christine; Spitz, Jerome; Authier, Matthieu; Romagnan, Jean-baptiste; Doray, Mathieu. Integrated marine survey series such as PELGAS provide comprehensive geo-referenced data over large sea areas in major ecosystem components with defined biological resolution and spatio-temporal sampling scale. These data enable to develop product at different levels of biological organization and spatial scale that are useful for ecosystem integrated assessments. Using the PELGAS integrated data series, we applied a generic procedure made of several steps to identify and map ecologically coherent ecosystem spatial units in the Bay of Biscay. First, the data were interpolated on a common spatial grid and organized as a time series of matrices containing at each time the variables as columns and the grid cell values as rows. The multi-table analysis method... Tipo: Text Palavras-chave: Integrated surveys; Ecosystems; Spatial structure; Multi-factor analysis; Bay of Biscay; Pelagic. Ano: 2018 URL: https://archimer.ifremer.fr/doc/00403/51402/51977.pdf Spatial variability of soil hydraulic properties on a steep slope in the loess plateau of China Scientia Agricola Hu,Wei; Shao,Ming An; Wang,Quan Jiu; Fan,Jun; Reichardt,Klaus. The understanding of the structure of the spatial variability of soil surface hydraulic properties on steep slopes is important for modeling infiltration and runoff processes. The objective of this study was to investigate the spatial variability of these properties on a steep slope of the Loess Plateau in northwest China. A 9600 m² area was systematically sampled in a grid of 106 points spaced 10 m x 10 m. Hydraulic properties were determined with a disc infiltrometer under multiple pressure heads (-15, -9, -6, -3, 0 cm) at each sample point. Classical and geo-statistical methods were used for data analysis. The results indicated that the variation of Gardner's a and hydraulic conductivities at all applied pressure heads was moderate and the heterogeneity... Tipo: Info:eu-repo/semantics/article Palavras-chave: Disc infiltrometer; Steep sloping land; Pressure head; Spatial structure. Ano: 2008 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162008000300007 Local environmental controls of Atlantic Forest tree community assembly on a coastal continental island in southeastern Brazil Acta Botanica Nettesheim,Felipe Cito; Garbin,Mário Luís; Pereira,Marcos Gervasio; Araujo,Dorothy Sue Dunn de. ABSTRACT Tropical forests with high species diversity are commonly found in rugged montane areas. We investigated causes of local tropical forest tree community assembly on a continental island with heterogeneous terrain. We recorded tree community (absolute species abundance), topography, soil, litter and location in 40 sampling units on two opposite sides of the island with similar heterogeneous terrain. We used transformation based Redundancy Analyses and variation partitioning to determine the contribution of environment (topography, soil and litter), spatial structure (geographic location and Moran Eigenvector Maps) and the shared effects of these to explain community assembly. The environment made a significant contribution to explain tree community... Tipo: Info:eu-repo/semantics/article Palavras-chave: Community composition; Community structure; Floristics; Neutral; Niche; Soil; Spatial structure; Topography; Tropical forest. Ano: 2019 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-33062019000100088 Heterogeneous genetic structure in a natural population of Raulí (Nothofagus nervosa) Ciencia e Investigación Agraria Carrasco,Basilio; Eaton,Lafayette; Letelier,Luis; Díaz,Carole; García-Gonzáles,Rolando. Heterozygote deficiencies in natural populations of outbreeding tree species are common and thought to be due mainly to biparental inbreeding. Inbreeding is believed to be caused by family structure within populations, a product of limited seed dispersal and probably limited pollen dispersal. Although both theory and simulation studies predict that structure should be apparent where trees are isolated by distance, most studies of structure in natural populations have detected only a weak spatial genetic structuring. In this contribution, we compare the use of spatial autocorrelation methodology and F statistics with the concept of relatedness to examine the spatial genetic structure in the natural population of a native southern beech and to explore the... Tipo: Journal article Palavras-chave: Genetic structure; Spatial structure; Raulí; Spatial autocorrelation. Ano: 2011 URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-16202011000300014 Registros recuperados: 6 Primeira ... 1 ... Última

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