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You searched for subject:(latitudinal patterns). Showing records 1 – 3 of 3 total matches.

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University of Oulu

1. Astorga, A. (Anna). Diversity patterns in marine and freshwater environments:the role of environmental and spatial factors across multiple scales.

Degree: 2009, University of Oulu

Abstract Recognition of the importance of a regional perspective for understanding the structure and dynamics of local assemblages has stimulated the emergence of the field of macroecology. Most attention has been directed to terrestrial ecosystems, while large-scale patterns in biodiversity of aquatic organisms have received less attention. In this thesis I examined patterns of aquatic diversity across several geographic areas and scales, in an effort to understand some of the environmental and spatial factors determining species diversity in aquatic environments. The main objectives of this thesis were: (i) to examine the latitudinal diversity patterns of marine crustaceans and molluscs and their relationship to large scale environmental gradients, (ii) to study macroinvertebrate species richness in headwater streams at two spatial extents, within and across drainage systems, and assess the relative importance of local, landscape and regional variables, and (iii) to study diversity patterns of macroorganisms vs microorganism, comparing distance decay patterns of stream diatoms, macroinvertebrates and bryophytes. Latitudinal diversity patterns of crustaceans and molluscs were clearly related to larval developmental mode. An increase in species richness towards high latitudes was found for species with direct development, whereas richness of species with planktotrophic development decreased poleward. Sea surface temperature was the most important environmental gradient related to species richness of both phyla and each developmental mode, but with different effects on each mode. Stream macroinvertebrate species richness at the bioregion extent was negatively related to water humic content. Another factor related to species richness at the bioregion extent was elevation range, a variable linked to stream topographic heterogeneity. Local environmental variables explained most of the variation in species richness at the drainage system extent, however high among-region variability was evident. Patterns between macro- and microorganism may not be fundamentally different, but the level of environmental control varied, being strongest for diatoms, while some groups of benthic macroinvertebrates exhibited relatively strong dispersal limitation. The relative importance of niche vs. dispersal processes is not simply a function of organism size but other traits (e.g. life-history type, dispersal capacity) may obscure this relationship.

Subjects/Keywords: biodiversity; community similarity; environmental gradients; latitudinal patterns; marine; spatial scale; spatial structure; species richness; streams

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Astorga, A. (. (2009). Diversity patterns in marine and freshwater environments:the role of environmental and spatial factors across multiple scales. (Doctoral Dissertation). University of Oulu. Retrieved from http://urn.fi/urn:isbn:9789514292293

Chicago Manual of Style (16th Edition):

Astorga, A (Anna). “Diversity patterns in marine and freshwater environments:the role of environmental and spatial factors across multiple scales.” 2009. Doctoral Dissertation, University of Oulu. Accessed January 20, 2020. http://urn.fi/urn:isbn:9789514292293.

MLA Handbook (7th Edition):

Astorga, A (Anna). “Diversity patterns in marine and freshwater environments:the role of environmental and spatial factors across multiple scales.” 2009. Web. 20 Jan 2020.

Vancouver:

Astorga A(. Diversity patterns in marine and freshwater environments:the role of environmental and spatial factors across multiple scales. [Internet] [Doctoral dissertation]. University of Oulu; 2009. [cited 2020 Jan 20]. Available from: http://urn.fi/urn:isbn:9789514292293.

Council of Science Editors:

Astorga A(. Diversity patterns in marine and freshwater environments:the role of environmental and spatial factors across multiple scales. [Doctoral Dissertation]. University of Oulu; 2009. Available from: http://urn.fi/urn:isbn:9789514292293

2. Hernáez Bové, Patricio Alejandro. Estado taxonômico e história de vida de Callichirus seilacheri (Bott, 1955) (Decapoda, Axiidea, Callianassidae) na costa do Pacífico Leste: ecologia reprodutiva em ambientes tropicais e relação entre a abundância e a variabilidade latitudinal dos atributos populacionais na costa do Chile.

Degree: PhD, Biologia Comparada, 2014, University of São Paulo

O camarão corrupto Callichirus seilacheri foi erigido por Bott (1955) através de uma breve e incompleta descrição carente da maioria das ilustrações sobre as principais estruturas corporais desta espécie. Callichirus seilacheri é considerada, atualmente, como o único representante do gênero Callichirus na costa do Pacífico Leste. Sua distribuição geográfica abrange um amplo gradiente latitudinal de aproximadamente 50º graus (~13º N - 37º S) desde a praia Los Blancos (localidade-tipo), El Salvador até Lenga na costa de Chile. O estado taxonômico da grande população de C. seilacheri tem sido questionado no passado em reiteradas oportunidades. Este questionamento tem relação com a falta de estudos taxonômicos associados com estas populações e com o fato que alguns antecedentes moleculares têm demonstrado que as populações de Callichirus da costa do Pacífico de Nicarágua e México são diferentes. Considerando estes antecedentes, o primero objetivo do presente estudo foi avaliar o estado taxonômico de C. seilacheri na costa do Pacífico Leste da América Central. Para isto, foi coletado material de C. seilacheri em diferentes localidades da costa do Pacifico de América Central, incluindo a localidade-tipo desta espécie na costa de El Salvador. Conforme as observações morfológicas do material coletado, os caracteres diagnósticos de C. seilacheri incluem entre outros aspectos: (i) pedúnculos oculares com uma alongada projeção pré-córneal, cujas pontas divergem lateralmente; (ii) segmentos terminais do pedúnculo antênular e antenal com as bases paralelas; e (iii) pereiópodo maior do primeiro par de pereiópodos dos machos adultos com o mero armado de um lóbulo retangular na região ventral anterior e ísquio curvado para baixo com um gancho na margem ventral. Uma das descobertas mais relevantes foi que todas as fêmeas de C. seilacheri têm ambos gonóporos masculino e feminino, o qual representa o primeiro registro de intersexualidade no gênero Callichirus. O segundo objetivo desta tese foi avaliar se a espécie da costa chilena Callichirus garthi (Retamal, 1975), considerada como uma sinonímia-junior de C. seilacheri da costa do Pacífico da América Central, é uma espécie válida. Para isto, comparou-se o material-tipo de C. garthi e outros lotes desta espécie coletados ao longo da costa de Chile (~18º e 37º S) com os espécimes de C. seilacheri coletados na localidade-tipo (Playa Los Blancos, El Salvador) e em outras localidades da América Central. A comparação morfológica revelou importantes diferenças morfológicas entre os tipos morfológicos identificados em ambas espécies. Entre as principais diferenças e possível mencionar que C. garthi possui as pontas dos pedúnculos oculares paralelas, enquanto que em C. seilacheri são divergentes formando um angulo de 60-70°. Os machos adultos de ambas espécies compartilham quelípodos desiguais na fase adulta, mas somente, C. seilacheri tem um gancho sobre a margem ventral do ísquio e um lóbulo meral retangular. A analise morfológica do material biológico coletado em ambas regiões permite… Advisors/Committee Members: Castro, Ricardo Macedo Corrêa e.

Subjects/Keywords: Biologia reprodutiva; Camarões corruptos; Easterb Pacific; Ghost shrimps; Latitudinal patterns; Pacífico este de América; Padrões latitudinais; Reproductive biology; Taxonomia; Taxonomy

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Hernáez Bové, P. A. (2014). Estado taxonômico e história de vida de Callichirus seilacheri (Bott, 1955) (Decapoda, Axiidea, Callianassidae) na costa do Pacífico Leste: ecologia reprodutiva em ambientes tropicais e relação entre a abundância e a variabilidade latitudinal dos atributos populacionais na costa do Chile. (Doctoral Dissertation). University of São Paulo. Retrieved from http://www.teses.usp.br/teses/disponiveis/59/59139/tde-02012015-165020/ ;

Chicago Manual of Style (16th Edition):

Hernáez Bové, Patricio Alejandro. “Estado taxonômico e história de vida de Callichirus seilacheri (Bott, 1955) (Decapoda, Axiidea, Callianassidae) na costa do Pacífico Leste: ecologia reprodutiva em ambientes tropicais e relação entre a abundância e a variabilidade latitudinal dos atributos populacionais na costa do Chile.” 2014. Doctoral Dissertation, University of São Paulo. Accessed January 20, 2020. http://www.teses.usp.br/teses/disponiveis/59/59139/tde-02012015-165020/ ;.

MLA Handbook (7th Edition):

Hernáez Bové, Patricio Alejandro. “Estado taxonômico e história de vida de Callichirus seilacheri (Bott, 1955) (Decapoda, Axiidea, Callianassidae) na costa do Pacífico Leste: ecologia reprodutiva em ambientes tropicais e relação entre a abundância e a variabilidade latitudinal dos atributos populacionais na costa do Chile.” 2014. Web. 20 Jan 2020.

Vancouver:

Hernáez Bové PA. Estado taxonômico e história de vida de Callichirus seilacheri (Bott, 1955) (Decapoda, Axiidea, Callianassidae) na costa do Pacífico Leste: ecologia reprodutiva em ambientes tropicais e relação entre a abundância e a variabilidade latitudinal dos atributos populacionais na costa do Chile. [Internet] [Doctoral dissertation]. University of São Paulo; 2014. [cited 2020 Jan 20]. Available from: http://www.teses.usp.br/teses/disponiveis/59/59139/tde-02012015-165020/ ;.

Council of Science Editors:

Hernáez Bové PA. Estado taxonômico e história de vida de Callichirus seilacheri (Bott, 1955) (Decapoda, Axiidea, Callianassidae) na costa do Pacífico Leste: ecologia reprodutiva em ambientes tropicais e relação entre a abundância e a variabilidade latitudinal dos atributos populacionais na costa do Chile. [Doctoral Dissertation]. University of São Paulo; 2014. Available from: http://www.teses.usp.br/teses/disponiveis/59/59139/tde-02012015-165020/ ;

3. Villamarín Flores, Christian Patricio. Estructura y composición de las comunidades de macroinvertebrados acuáticos en ríos altoandinos del Ecuador y Perú. Diseño de un sistema de medida de la calidad del agua con índices multimétricos.

Degree: Departament d'Ecologia, 2012, Universitat de Barcelona

STRUCTURE AND COMPOSITION OF AQUATIC MACROINVERTEBRATES COMMUNITIES IN HIGHLAND ANDEAN RIVERS OF ECUADOR AND PERU. DESIGN OF A MEASURE OF WATER QUALITY WITH MULTIMETRIC INDEXES In this thesis we sampled Highland Andean Rivers above 2000 m a.s.l. (tropical andean highland rivers) which are distributed in a wide geographical region of the North Andes (Ecuador) and Central Andes (Peru) in South America. In total 123 sites were sampled in dry season, which were selected taking into account the anthropogenic influence gradient, ranging from no alteration, little alteration (i.e., reference) to highly altered. The physico-chemical caracteristics of rivers showed a high altitud influence. We recorded a decrease in both temperature and oxygen as altitude increases. Habitat heterogeneity and the riverine forest quality were identified as determinant enviromental characteristics regarding the andean higland rivers studied. The mineralization show differences between the morphotectonics groups, while were the conductivity was higher at the south, depending on the geomorphology of each zone. The sampled macroinvertebrate assemblages were influenced by both latitudinal and altitudinal gradients. In detail, assemblages showed different gradient responses (positive or negative), depending of the organism and its requirements. The patterns of abundance and richness are probably determined by the environmental variability observed, and described by the temperature, oxygen, habitat heterogeneity and the presence, and absence of riverine forest. The family Chironomidae, as we expected, showed different responses depending of the genus, while the composition of the family was determined mainly by temperature, oxygen, lithography. and biogeography. We also studied the biodiversity patterns of Highland Andean Rivers rivers. The benthic community assemblage showed a high variability at local diversity (alpha diversity), while the gamma diversity decreased in both latitude and altitude gradients. Moreover, the community presented some discontinuities in the beta diversity. Regarding latitudinal gradient, the composition of assemblage changed in each morphological group, while altitude changes were described by vegetation types (mountain forest or páramo-puna) or presence or absence of riverine forest. Finally, using the aquatic macroinvertebrate communities of the reference sites, two different zones were identified as distinct from each other: from 2000 to 3500 m a.s.l and those sites at altitudes higher than 3500 m a.sl.. For such reasons two versions of a multi-metric index - the IMEERA index - were developed. The IMEERA B index includes six metrics evaluating richness, habit and tolerance/intolerance. The IMEERA P index was calculated using four metrics evaluating richness and tolerance/intolerance. Results showed that in lower altitudes (Bosque river type, IMEERA-B index), the pressure gradient was driven by the organic pollution and the hydromorphological degradation, while in higher altitudes (Páramo and Puna river types;… Advisors/Committee Members: [email protected] (authoremail), false (authoremailshow), Prat i Fornells, Narcís (director), Rieradevall i Sant, Maria (director), true (authorsendemail).

Subjects/Keywords: Comunidad de macroinvertebrados acuáticos; Comunitat de macroinvertebrats aquàtics; Aquatic macroinvertebrate community; Patrones de distribución altitudinales y latitudinales; Patrons de distribució altitudinals i latitudinals; Altitudinal and latitudinal distribution patterns; Índice multimétrico de calidad ecológica; Índex multimètric de qualitat ecològica; Ecological quality multimetric index; Ciències Experimentals i Matemàtiques; 574

…se pretende estudiar la influencia del gradiente tanto latitudinal como altitudinal, lo que… …altoandina tropical. La zona de estudio y sus características Los Andes: El gradiente latitudinal… …largo del gradiente latitudinal. 13 Introducción General: LOS RÍOS ALTOANDINOS TROPICALES… …gradiente latitudinal en cambio, estaría determinado por la geomorfología y por la climatología… …influencia sobre la comunidad a escala de la región andina, así como en el gradiente latitudinal… 

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Villamarín Flores, C. P. (2012). Estructura y composición de las comunidades de macroinvertebrados acuáticos en ríos altoandinos del Ecuador y Perú. Diseño de un sistema de medida de la calidad del agua con índices multimétricos. (Thesis). Universitat de Barcelona. Retrieved from http://hdl.handle.net/10803/83923

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16th Edition):

Villamarín Flores, Christian Patricio. “Estructura y composición de las comunidades de macroinvertebrados acuáticos en ríos altoandinos del Ecuador y Perú. Diseño de un sistema de medida de la calidad del agua con índices multimétricos.” 2012. Thesis, Universitat de Barcelona. Accessed January 20, 2020. http://hdl.handle.net/10803/83923.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7th Edition):

Villamarín Flores, Christian Patricio. “Estructura y composición de las comunidades de macroinvertebrados acuáticos en ríos altoandinos del Ecuador y Perú. Diseño de un sistema de medida de la calidad del agua con índices multimétricos.” 2012. Web. 20 Jan 2020.

Vancouver:

Villamarín Flores CP. Estructura y composición de las comunidades de macroinvertebrados acuáticos en ríos altoandinos del Ecuador y Perú. Diseño de un sistema de medida de la calidad del agua con índices multimétricos. [Internet] [Thesis]. Universitat de Barcelona; 2012. [cited 2020 Jan 20]. Available from: http://hdl.handle.net/10803/83923.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Villamarín Flores CP. Estructura y composición de las comunidades de macroinvertebrados acuáticos en ríos altoandinos del Ecuador y Perú. Diseño de un sistema de medida de la calidad del agua con índices multimétricos. [Thesis]. Universitat de Barcelona; 2012. Available from: http://hdl.handle.net/10803/83923

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

.