Vegetation of the Siskiyou Mountains, Oregon and California

Whittaker, R. H.

doi:10.2307/1943563

Cited by 3,270 publications

(2,396 citation statements)

References 116 publications

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“…The alpha diversity (or richness) and abundance (Whittaker, 1960;Legendre et al, 2005) were higher in Bonita and Gansos lakes, facts that explain the higher diversity (Magurran, 2001;Jabiol et al, 2013). This result may be explained by environmental variables (e.g.…”

Section: Factors That Structure the Alpha Diversity Of Zooplankton Comentioning

confidence: 89%

“…Multivariate dispersion (functions betadiver, Vegan package for R version 2.0.8; Oksanen et al, 2008) estimates the β diversity as sampling points average dissimilarity (i.e., distance) from their group centroid in a multivariate space. The comparison among sampling points was based on the Whittaker index (βw; Whittaker, 1960;Magurran, 2001) as proposed by Koleff et al (2003). According to Koleff et al (2003), βw is the most widely used β diversity measure in Ecology and the values show a simple relation to variation in that whole scale negatively with increase in the matching component.…”

Section: Measuring the Diversity Indexmentioning

confidence: 99%

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Factors that drive zooplankton diversity in Neo-Tropical Savannah shallow lakes

Padovesi-Fonseca

Rezende

2017

Acta Limnol. Bras.

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Abstract:Zooplankton is an important community in aquatic ecosystems due to its linkage between primary producers and secondary consumers also playing a key role in cycling of organic materials. Aim: Therefore, our objective was to evaluate the effects of physicochemical variables of the water on the diversity of zooplankton community in seven tropical shallow lakes of Brazilian savannah. Methods: Zooplankton samples were taken using a bucket and filtered 200 L by a 64 µm-mesh-plankton-net, and preserved for subsequent identification. Water temperature, dissolved oxygen, pH, electrical conductivity, turbidity, chlorophyll-a, ammonium, nitrate, nitrite, total phosphorus, and soluble reactive phosphorus were measured. Results: The turbidity (decreases the temperature, luminosity and the system productivity) and ammonium (increases the toxicity) values were the major factors responsible for structuring the zooplankton community. On the other hand, also nitrogen and phosphorus (increase the productivity) are limiting in savannah lentic systems for the zooplankton. The higher α diversity was positively associated with aquatic macrophytes (increase of niches and refuge), whereas lakes with geographic proximity increase the similarity in species composition, decreasing the β diversity. Conclusions: We conclude that the deterministic processes (niche theory), due to species have different ecological requirements, are different responses to environmental gradients and increase the diversity in heterogenic lentic systems.Keywords: α diversity; β diversity; nutrients; habitat heterogeneity; lentic systems.Resumo: O zooplâncton é uma comunidade importante nos ecossistemas aquáticos por ser o elo entre os produtores primários e os consumidores secundários, além de desempenharem um papel fundamental no ciclo de materiais orgânicos. Objetivo: Nosso objetivo foi avaliar os efeitos das variáveis físicas e químicas da água na diversidade de zooplâncton em sete lagoas rasas tropicais da savana brasileira. Métodos: As amostras de zooplâncton foram coletadas usando balde e filtrando 200 litros em rede de plâncton com abertura de 64 µm, e preservadas para posterior identificação. A temperatura da água, oxigênio dissolvido, pH, condutividade elétrica, turbidez, clorofila-a, amônio, nitrato, nitrito, fósforo total, fósforo reativo solúvel, cobertura de macrófita da lamina d'água foram obtidos. Resultados: A turbidez (ao diminui a temperatura, a luminosidade e a produtividade do sistema) e os valores de amônio (por aumenta a toxicidade) foram os principais fatores responsáveis pela estruturação do zooplâncton. Por outro lado, o nitrogênio e o fósforo (por aumentar a produtividade) são limitantes para o zooplâncton nos sistemas lênticos de savana. A maior diversidade α foi associada 2 Padovesi-Fonseca, C. and Rezende, R.S.

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Section: Factors That Structure the Alpha Diversity Of Zooplankton Comentioning

confidence: 89%

Section: Measuring the Diversity Indexmentioning

confidence: 99%

Factors that drive zooplankton diversity in Neo-Tropical Savannah shallow lakes

Padovesi-Fonseca

Rezende

2017

Acta Limnol. Bras.

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“…For each national park, we estimated the three basic components of the diversity (sensu Whittaker, 1960). We define α‐diversity as the diversity measured on each forest type, β‐diversity as the species turnover between the forest types of each national park, and γ‐diversity as the diversity value measured on each national park as a whole (pooling the forest types).…”

Section: Methodsmentioning

confidence: 99%

Hidden diversity in forest soils: Characterization and comparison of terrestrial flatworm’s communities in two national parks in Spain

Álvarez‐Presas

Mateos

Riutort

2018

Ecology and Evolution

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Terrestrial flatworms (Platyhelminthes, Tricladida, and Geoplanidae) belong to what is known as cryptic soil fauna of humid forests and are animals not easily found or captured in traps. Nonetheless, they have been demonstrated to be good indicators of the conservation status of their habitat as well as a good model to reconstruct the recent and old events affecting biodiversity. This is mainly due to their delicate constitution, their dependence on the integrity of their habitat, and their very low dispersal capacity. At present, little is known about their communities, except for some studies performed in Brazil. In this work, we analyze for the first time in Europe terrestrial flatworm communities. We have selected two protected areas belonging to the Red Española de Parques Nacionales. Our aims include performing a first study of the species richness and community structure for European terrestrial planarian species at regional and local scale. We evaluate the effect of type of forests in the community composition and flatworms’ abundance, but also have into account the phylogenetic framework (never considered in previous studies) analyzed based on molecular data. We find differences in the species composition among parks, with an astonishingly high diversity of endemic species in the Parque Nacional de Picos de Europa and an extremely low diversity of species in the Parque Nacional de Ordesa y Monte Perdido. These divergent patterns cannot be attributed to differences in physical variables, and in addition, the analyses of their phylogenetic relationships and, for a few species, their genetic structure, point to a more probable historical explanation.

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“…In both years, the September cruises showed statistically significant higher values with 0.8 in 2010 and 0.85 in 2011 (p b 0.05 according to an ANOVA), indicating a more diverse community than in the other seasons. Seasonal differences were also found with respect to the spatial variability of community composition, which can be expressed as beta-diversity (Whittaker, 1960). Calculated from taxa presence/absence, beta diversity (and therefore spatial heterogeneity of the communities) was higher in summer (3.29 in July 2010 and 3.52 in June 2011), than in spring (2.87 in April 2011), while it was the lowest in September of both years (1.13 in 2010 and 1.4 in 2011).…”

Section: Microscopic Observationsmentioning

confidence: 99%

Analysis of phytoplankton distribution and community structure in the German Bight with respect to the different size classes

Wollschläger

Wiltshire

Petersen

et al. 2015

Journal of Sea Research

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Investigation of phytoplankton biodiversity, ecology, and biogeography is crucial for understanding marine ecosystems. Research is often carried out on the basis of microscopic observations, but due to the limitations of this approach regarding detection and identification of picophytoplankton (0.2-2 μm) and nanophytoplankton (2-20 μm), these investigations are mainly focused on the microphytoplankton (20-200 μm). In the last decades, various methods based on optical and molecular biological approaches have evolved which enable a more rapid and convenient analysis of phytoplankton samples and a more detailed assessment of small phytoplankton. In this study, a selection of these methods (in situ fluorescence, flow cytometry, genetic fingerprinting, and DNA microarray) was placed in complement to light microscopy and HPLC-based pigment analysis to investigate both biomass distribution and community structure of phytoplankton. As far as possible, the size classes were analyzed separately. Investigations were carried out on six cruises in the German Bight in 2010 and 2011 to analyze both spatial and seasonal variability. Microphytoplankton was identified as the major contributor to biomass in all seasons, followed by the nanophytoplankton. Generally, biomass distribution was patchy, but the overall contribution of small phytoplankton was higher in offshore areas and also in areas exhibiting higher turbidity. Regarding temporal development of the community, differences between the small phytoplankton community and the microphytoplankton were found. The latter exhibited a seasonal pattern regarding number of taxa present, alphaand beta-diversity, and community structure, while for the nano-and especially the picophytoplankton, a general shift in the community between both years was observable without seasonality. Although the reason for this shift remains unclear, the results imply a different response of large and small phytoplankton to environmental influences.

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Vegetation of the Siskiyou Mountains, Oregon and California

Cited by 3,270 publications

References 116 publications

Factors that drive zooplankton diversity in Neo-Tropical Savannah shallow lakes

Factors that drive zooplankton diversity in Neo-Tropical Savannah shallow lakes

Hidden diversity in forest soils: Characterization and comparison of terrestrial flatworm’s communities in two national parks in Spain

Analysis of phytoplankton distribution and community structure in the German Bight with respect to the different size classes

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