scholarly journals Patterns in Alpha and Beta Phytoplankton Diversity along a Conductivity Gradient in Coastal Mediterranean Lagoons

Diversity ◽  
2020 ◽  
Vol 12 (1) ◽  
pp. 38 ◽  
Author(s):  
Natassa Stefanidou ◽  
Matina Katsiapi ◽  
Dimitris Tsianis ◽  
Maria Demertzioglou ◽  
Evangelia Michaloudi ◽  
...  
Keyword(s):  
Beta Diversity ◽  
Algal Blooms ◽  
Species Turnover ◽  
Coastal Lagoons ◽  
Prorocentrum Minimum ◽  
Diversity Patterns ◽  
Alpha And Beta Diversity ◽  
Mediterranean Lagoons ◽  
Phytoplankton Communities ◽  
Wide Range

Understanding the diversity patterns of phytoplankton assemblages in coastal lagoons is clearly important for water management. In this study, we explored alpha and beta diversity patterns in phytoplankton communities across five Mediterranean lagoons hydrologically connected to Vistonikos Gulf. We examined the phytoplankton community composition and biomass on a monthly basis from November 2018 to October 2019. For this, water samples were collected from seven inshore, brackish and coastal waters, sampling sites covering a wide range of conductivity. We found significant spatial and temporal differences in phytoplankton alpha diversity and in phytoplankton biomass metrics explained by the high variation of conductivity. Evenness remained low throughout the study period, reflecting significant dominance of several phytoplankton blooms. Harmful algal blooms of Prorocentrum minimum, Alexandrium sp., Rhizosolenia setigera and Cylindrotheca closterium occurred. The system’s species pool was characterized by relatively high phytoplankton beta diversity (average ~0.7) resulting from high temporal species turnover (90%). Overall, alpha and beta diversity components were indicative of rather heterogeneous phytoplankton communities which were associated with the high differences in conductivity among the sampling sites.

scholarly journals Alpha and beta diversity patterns of polychaete assemblages across the nodule province of the eastern Clarion-Clipperton Fracture Zone (equatorial Pacific)

2020 ◽  
Vol 17 (4) ◽  
pp. 865-886 ◽  
Author(s):  
Paulo Bonifácio ◽  
Pedro Martínez Arbizu ◽  
Lénaïck Menot
Keyword(s):  
Fracture Zone ◽  
Beta Diversity ◽  
Species Turnover ◽  
Regional Scale ◽  
Equatorial Pacific ◽  
Equatorial Pacific Ocean ◽  
Species Ranges ◽  
Diversity Patterns ◽  
Clipperton Fracture Zone ◽  
Clarion Clipperton Fracture Zone

Abstract. In the abyssal equatorial Pacific Ocean, most of the seafloor of the Clarion-Clipperton Fracture Zone (CCFZ), a 6 million km2 polymetallic nodule province, has been preempted for future mining. In light of the large environmental footprint that mining would leave and given the diversity and the vulnerability of the abyssal fauna, the International Seabed Authority has implemented a regional management plan that includes the creation of nine Areas of Particular Environmental Interest (APEIs) located at the periphery of the CCFZ. The scientific principles for the design of the APEIs were based on the best – albeit very limited – knowledge of the area. The fauna and habitats in the APEIs are unknown, as are species' ranges and the extent of biodiversity across the CCFZ. As part of the Joint Programming Initiative Healthy and Productive Seas and Oceans (JPI Oceans) pilot action “Ecological aspects of deep-sea mining”, the SO239 cruise provided data to improve species inventories, determine species ranges, identify the drivers of beta diversity patterns and assess the representativeness of an APEI. Four exploration contract areas and an APEI (APEI no. 3) were sampled along a gradient of sea surface primary productivity that spanned a distance of 1440 km in the eastern CCFZ. Between three and eight quantitative box cores (0.25 m2; 0–10 cm) were sampled in each study area, resulting in a large collection of polychaetes that were morphologically and molecularly (cytochrome c oxidase subunit I and 16S genes) analyzed. A total of 275 polychaete morphospecies were identified. Only one morphospecies was shared among all five study areas and 49 % were singletons. The patterns in community structure and composition were mainly attributed to variations in organic carbon fluxes to the seafloor at the regional scale and nodule density at the local scale, thus supporting the main assumptions underlying the design of the APEIs. However, the APEI no. 3, which is located in an oligotrophic province and separated from the CCFZ by the Clarion Fracture Zone, showed the lowest densities, lowest diversity, and a very low and distant independent similarity in community composition compared to the contract areas, thus questioning the representativeness and the appropriateness of APEI no. 3 to meet its purpose of diversity preservation. Among the four exploration contracts, which belong to a mesotrophic province, the distance decay of similarity provided a species turnover of 0.04 species km−1, an average species range of 25 km and an extrapolated richness of up to 240 000 polychaete species in the CCFZ. By contrast, nonparametric estimators of diversity predict a regional richness of up to 498 species. Both estimates are biased by the high frequency of singletons in the dataset, which likely result from under-sampling and merely reflect our level of uncertainty. The assessment of potential risks and scales of biodiversity loss due to nodule mining thus requires an appropriate inventory of species richness in the CCFZ.

scholarly journals Robust, data-driven bioregionalizations emerge from diversity concordance

2021 ◽  
Author(s):  
Cristian S. Montalvo-Mancheno ◽  
Jessie Buettel ◽  
Stefania Ondei ◽  
Barry W. Brook
Keyword(s):  
Species Diversity ◽  
Beta Diversity ◽  
Alpha Diversity ◽  
Data Driven ◽  
Conservation Units ◽  
Conservation Action ◽  
Diversity Patterns ◽  
Alpha And Beta Diversity ◽  
Terrestrial Vertebrates ◽  
Site Diversity

Aim: Despite the increasing interest in developing new bioregionalizations and assessing the most widely accepted biogeographic frameworks, no study to date has sought to systematically define a system of small bioregions nested within larger ones that better reflect the distribution and patterns of biodiversity. Here, we examine how an algorithmic, data-driven model of diversity patterns can lead to an ecologically interpretable hierarchy of bioregions. Location: Australia. Time period: Present. Major taxa studied: Terrestrial vertebrates and vascular plants. Methods: We compiled information on the biophysical characteristics and species occupancy of Australia′s geographic conservation units (bioregions). Then, using cluster analysis to identify groupings of bioregions representing optimal discrete-species areas, we evaluated what a hierarchical bioregionalization system would look like when based empirically on the within- and between-site diversity patterns across taxa. Within an information-analytical framework, we then assessed the degree to which the World Wildlife Fund′s (WWF) biomes and ecoregions and our suite of discrete-species areas are spatially associated and compared those results among bioregionalization scenarios. Results: Information on biodiversity patterns captured was moderate for WWF′s biomes (50–58% for birds′ beta, and plants′ alpha and beta diversity, of optimal discrete areas, respectively) and ecoregions (additional 4–25%). Our plants and vertebrate optimal areas retained more information on alpha and beta diversity across taxa, with the two algorithmically derived biogeographic scenarios sharing 86.5% of their within- and between-site diversity information. Notably, discrete-species areas for beta diversity were parsimonious with respect to those for alpha diversity. Main conclusions: Nested systems of bioregions must systematically account for the variation of species diversity across taxa if biodiversity research and conservation action are to be most effective across multiple spatial or temporal planning scales. By demonstrating an algorithmic rather than subjective method for defining bioregionalizations using species-diversity concordances, which reliably reflects the distributional patterns of multiple taxa, this work offers a valuable new tool for systematic conservation planning.

scholarly journals Alpha and beta diversity patterns of polychaete assemblages across the nodule province of the Clarion-Clipperton Fracture Zone (Equatorial Pacific)

2019 ◽  
Author(s):  
Paulo Bonifácio ◽  
Pedro Martinez-Arbizu ◽  
Lénaïck Menot
Keyword(s):  
Fracture Zone ◽  
Beta Diversity ◽  
Species Turnover ◽  
Regional Scale ◽  
Equatorial Pacific ◽  
Equatorial Pacific Ocean ◽  
Species Ranges ◽  
Diversity Patterns ◽  
Clipperton Fracture Zone ◽  
Clarion Clipperton Fracture Zone

Abstract. In the abyssal Equatorial Pacific Ocean, most of the seafloor of the Clarion-Clipperton Fracture Zone (CCFZ), a 6 million km2 polymetallic nodule province, has been preempted for future mining. In light of the large footprint that mining would leave, and given the diversity and the vulnerability of the abyssal fauna, the International Seabed Authority has implemented a regional management plan that includes the creation of nine areas of particular environmental interest (APEIs) located at the periphery of the CCFZ. The APEIs were defined based on the best – albeit very limited – scientific knowledge for the area. The fauna and habitats in the APEIs are unknown, as are species' ranges and the extent of biodiversity across the CCFZ. As part of the Joint Programming Initiative Healthy and Productive Seas and Oceans (JPI Oceans) pilot action Ecological aspects of deep-sea mining, the SO239 cruise aimed at improving species inventories, determining species ranges, identifying the drivers of beta diversity patterns and assessing the representativeness of an APEI. Four exploration contract areas and an APEI (APEI#3) were sampled along a gradient of sea-surface primary productivity that spanned a distance of 1440 km in the eastern CCFZ. Between 3 and 8 quantitative box cores (0.25 m2; 0–10 cm) were sampled in each study area, resulting in a large collection of polychaetes that were morphologically and molecularly (COI and 16S genes) analyzed. A total of 275 polychaete morphotypes were identified. Only one morphotype was shared among all five study areas and 49 % were singletons. The patterns in community structure and composition were mainly attributed to variations in food fluxes at the regional scale and nodule density at the local scale. The four exploration contract areas belong to a mesotrophic province. The distance-decay of similarity among the four areas provides an estimated species turnover of 0.04 species km−1 and an average species range of 25 km. The polychaete assemblage in APEI#3 showed the lowest densities, lowest diversity as well as very low, distant-independent similarity with the other four study areas. Given that APEI#3 is located in an oligotrophic province and separated from the CCFZ by the Clarion Fracture Zone, our results call into question the representativeness and the appropriateness of APEI#3 to meet its purpose of preserving the biodiversity of the CCFZ fauna. Two methods for estimating the total number of polychaete species gave estimates that ranged from 498 to 240 000 species. Both methods are biased by the high frequency of singletons in the dataset, which likely result from under-sampling; our estimates thereby merely reflect our level of uncertainty. The assessment of potential risks and scales of biodiversity loss due to nodule mining thus requires an appropriate inventory of species richness in the CCFZ.

scholarly journals Diversity of epiphyte ferns along an elevational gradient in El Triunfo Biosphere Reserve, southern Mexico

2020 ◽  
Vol 153 (1) ◽  
pp. 12-21
Author(s):  
Derio A. Jiménez-López ◽  
Rubén Martínez-Camilo ◽  
Nayely Martínez-Meléndez ◽  
Michael Kessler
Keyword(s):  
Linear Regression ◽  
Beta Diversity ◽  
Species Turnover ◽  
Cloud Forest ◽  
Alpha Diversity ◽  
Elevational Gradient ◽  
Mountain Range ◽  
Southern Mexico ◽  
Diversity Patterns ◽  
Individual Trees

Background and aims – In the tropics, some studies have found that the richness of epiphytic ferns present a peak at mountain mid-elevations. However, it is not well understood how transitions from tropical to subtropical conditions affect this peak, and even less is known about beta diversity of epiphytic ferns. Thus, the objective is to understand the effect of climatic gradients on the variation of local richness of ferns and beta diversity patterns along an elevational gradient in a mountain system in southern Mexico.Methods – We sampled 32 trees, each in four elevational bands (100–2200 m). Alpha diversity patterns were analysed using linear regression models. We used the Morisita index to quantify species turnover between bands. An additive partitioning approach was used to analyse the degree to which individual trees, plots, and bands contributed to total species richness. We evaluated the influence of climatic variables on species composition via linear regression models.Key results – A total of 30 species in five families were recorded. Each family contributed in different magnitude to the elevational richness pattern, with Polypodiaceae dominating due to its richness and presence along the entire transect. Alpha diversity at the three scales (αtree, αplot, αband) increased with elevation and rainfall, and with decreasing temperature. Species turnover was high along the gradient, but was scale-dependent, with βtransect (65–75%) and βband (14%) with the greatest contributing to total diversity. Although the contribution of the individual trees was lower, it increased with elevation. Conclusions – We emphasize the importance of including different scale levels in analyses of diversity along elevational gradients. In the region, cloud forest on the mountain peaks harbours the highest diversity of epiphytic fern communities. Due to a limited extent of this mountain range, the epiphyte ferns are susceptible to the effects of climate change.

scholarly journals Historical signatures in the alpha and beta diversity patterns of Atlantic Forest harvestman communities (Arachnida: Opiliones)

2019 ◽  
Vol 97 (7) ◽  
pp. 631-643 ◽  
Author(s):  
A.A. Nogueira ◽  
C. Bragagnolo ◽  
M.B. DaSilva ◽  
T.K. Martins ◽  
E.P. Lorenzo ◽  
...  
Keyword(s):  
Protected Areas ◽  
Atlantic Forest ◽  
Beta Diversity ◽  
Alpha Diversity ◽  
Influential Factor ◽  
Conservation Strategies ◽  
Diversity Patterns ◽  
Alpha And Beta Diversity ◽  
Historical Factors ◽  
Compositional Changes

The integration of ecology and historical biogeography is fostering the investigation of diversity patterns. We studied alpha and beta diversity patterns of Brazilian Atlantic Forest harvestman (Arachnida: Opiliones) communities and related them to environmental and historical factors. Our data bank contains 508 species from 63 sites, encompassing almost the entire latitudinal range of Atlantic Forest. Alpha diversity was higher in coastal sites in the south and southeast regions and decreased in sites inland, as well as in sites in the coastal northeast region, especially in northern Bahia state. Alpha diversity was positively influenced by precipitation and altitudinal range, but the low number of species in northeastern coastal sites seems to be more related to the historical distribution of Neotropical harvestman lineages than to recent environmental factors. Geographic distance was the most influential factor for beta diversity. Compositional changes were also remarkably congruent with areas of endemism delimited for Atlantic Forest harvestmen. The percentage of protected areas for each area of endemism was very unbalanced, and Espírito Santo and Pernambuco states were the least protected areas. The turnover process observed in the compositional changes indicates that conservation strategies should include as many reserves as possible because every community presents a unique set of species.

scholarly journals Supporting global biodiversity assessment through high-resolution macroecological modelling: Methodological underpinnings of the BILBI framework

2018 ◽  
Author(s):  
Andrew J Hoskins ◽  
Thomas D Harwood ◽  
Chris Ware ◽  
Kristen J Williams ◽  
Justin J Perry ◽  
...  
Keyword(s):  
Beta Diversity ◽  
Biodiversity Assessment ◽  
Environmental Predictors ◽  
Ecological Processes ◽  
Biodiversity Indicators ◽  
Diversity Patterns ◽  
Biodiversity Surrogates ◽  
Alpha And Beta Diversity ◽  
Habitat Transformation ◽  
Global Biodiversity

ABSTRACTAimGlobal indicators of change in the state of terrestrial biodiversity are often derived by intersecting observed or projected changes in the distribution of habitat transformation, or of protected areas, with underlying patterns in the distribution of biodiversity. However the two main sources of data used to account for biodiversity patterns in such assessments – i.e. ecoregional boundaries, and vertebrate species ranges – are typically delineated at a much coarser resolution than the spatial grain of key ecological processes shaping both land-use and biological distributions at landscape scale. Species distribution modelling provides one widely used means of refining the resolution of mapped species distributions, but is limited to a subset of species which is biased both taxonomically and geographically, with some regions of the world lacking adequate data to generate reliable models even for better-known biological groups.InnovationMacroecological modelling of collective properties of biodiversity (e.g. alpha and beta diversity) as a correlative function of environmental predictors offers an alternative, yet highly complementary, approach to refining the spatial resolution with which patterns in the distribution of biodiversity can be mapped across our planet. Here we introduce a new capability – BILBI (the Biogeographic Infrastructure for Large-scaled Biodiversity Indicators) – which has implemented this approach by integrating advances in macroecological modelling, biodiversity informatics, remote sensing and high-performance computing to assess spatial-temporal change in biodiversity at ~1km grid resolution across the entire terrestrial surface of the planet. The initial implementation of this infrastructure focuses on modelling beta-diversity patterns using a novel extension of generalised dissimilarity modelling (GDM) designed to extract maximum value from sparsely and unevenly distributed occurrence records for over 400,000 species of plants, invertebrates and vertebrates.Main conclusionsModels generated by BILBI greatly refine the mapping of beta-diversity patterns relative to more traditional biodiversity surrogates such as ecoregions. This capability is already proving of considerable value in informing global biodiversity assessment through: 1) generation of indicators of past-to-present change in biodiversity based on observed changes in habitat condition and protected-area coverage; and 2) projection of potential future change in biodiversity as a consequence of alternative scenarios of global change in drivers and policy options.

scholarly journals The Effects of Mixed Nut Consumption on the Microbiome in Healthy Adults

2020 ◽  
Vol 4 (Supplement_2) ◽  
pp. 1580-1580
Author(s):  
Martin Rosas ◽  
Changqi Liu ◽  
Celéste O'Mealy ◽  
Erica Forsberg ◽  
Shirin Hooshmand ◽  
...  
Keyword(s):  
Human Health ◽  
Beta Diversity ◽  
Bifidobacterium Longum ◽  
Fold Increase ◽  
Potato Chips ◽  
Rrna Gene ◽  
Significant Shift ◽  
Microbiota Composition ◽  
Alpha And Beta Diversity ◽  
Wide Range

Abstract Objectives Nut consumption has been shown to have a wide range of health benefits from lowering cholesterol to extending longevity. Due to their prebiotic content, one potential mechanism is that nuts favorably impact the symbiotic relationship of the gut microbiome. So far studies have investigated the role of individual types of nuts, but more research is needed to determine if favorable microbiota changes extend to a nut mixture, which is often how people consume nuts. The purpose of this study was to examine the effects of daily mixed nut consumption on microbiome diversity as it relates to human health. Methods Subjects (N = 20) were randomized into two groups either consuming 42g (250 Kcal) of mixed nuts (n = 10, 9 females, 1 male, age 24.5 ± 1.2 y, BMI 24.8 ± 1.5 kg/m2) containing cashews, almonds, pecans, peanuts, walnuts, pistachios, Brazil and macadamia nuts or 46g of iso-caloric lightly salted potato chips (n = 10, 8 females, 2 males, age 24.2 ± 1.0 y, BMI 23.3 ± 1.0 kg/m2) every day for three weeks. Stool samples were collected at baseline and week three in DNA/RNA shield solution and isolated DNA was sequenced using 16S rRNA gene sequencing. Microbiome data were analyzed for alpha and beta diversity and taxa abundance using R. Results The intervention did not lead to significant changes in microbiota composition at the phyla or genera level; however, a trend towards a decreased Bacteroidetes to Firmicutes ratio was observed after consumption of potato chips for three weeks while an opposite trend was observed following mixed nut consumption. For within-subject (alpha) and between-subject (beta) diversity there were no significant changes at the species level. A significant (P = 0.018) 11.9 log fold increase in Dialister invisus was observed in the potato chips group. Although not statistically significant, the mixed nuts group had a 7.1 log fold decrease in Prevotella bivia (P = 0.058), a 4.5 log fold decrease in Eubacterium dolichum and a 3.6 log fold increase in Bifidobacterium longum. Conclusions Results indicate that the consumption of mixed nuts did not lead to a significant shift in microbiota composition; however, trends at the phyla and species levels suggest a longer intervention may be needed to observe microbiota changes that may contribute to human health. Funding Sources American Heart Association (16GRNT31360007).

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