scholarly journals Patterns of Odonata Assemblages in Lotic and Lentic Systems in the Ankasa Conservation Area, Ghana

2019 ◽  
Vol 2019 ◽  
pp. 1-14
Author(s):  
Issah Seidu ◽  
Collins Ayine Nsor ◽  
Emmanuel Danquah ◽  
Paul Tehoda ◽  
Samuel K. Oppong
Keyword(s):  
Species Richness ◽  
Predictive Factors ◽  
Sampling Site ◽  
Species Abundance ◽  
Water Systems ◽  
Water Bodies ◽  
Freshwater Biodiversity ◽  
Sampling Protocol ◽  
Conservation Area ◽  
Stick Model

Our study examined Odonata assemblages distribution pattern and the predictive factors that accounted for this in the lotic and lentic water systems within the Ankasa Conservation Area (Ghana). A total of 23 sites with sampling protocol of 2 researchers per hour per sampling site were used to survey Odonata species over two seasons in the three water bodies (streams, rivers, and ponds). Broken stick model, individual-based rarefaction, and Renyi diversity ordering were employed to quantify community assemblages. Ordination technique was also used to determine the Odonata-environmental relationship. A total of 1403 individuals, belonging to 47 species (22 Zygoptera and 25 Anisoptera) in six families, were recorded. Species richness (Hc = 3.414, p = 0.169) and diversity (Hc = 1.661, p = 0.44) generally did not differ among the three water systems. However, from individual sites, ponds appeared mostly diverse (α-scale = 0.04, Renyi index (r) = 5.86 to α = 3.5, r = 3.12), in spite of their lowest species abundance and richness. At the suborder level, ponds equally exhibited the highest Anisoptera species richness (9.90 ± SE 0.640) compared with Zygopterans (0.80± SE 0.291). Overall, Anisopterans (K= 16.51, p= 0.00026) and Zygopterans richness (K= 16.39, p= 0.00023) differed significantly among the three subsystems, while Odonata composition also differed significantly among the various water bodies (ANOSIM: global R= 0.94, p<0.001). Flow rate, water temperature, channel width, and turbidity were the key predictive factors that influence the structure of Odonata species assemblages. The results highlight the need to improve the functional status of the lentic and lotic systems, with the ultimate goal of conserving diverse Odonata fauna and other sympatric freshwater biodiversity.

scholarly journals A New, Ecologically Self-Significant Metric of Species-Abundance Unevenness, Reliably Highlighting the Intensity of Interspecific Competition

2021 ◽  
pp. 48-71
Author(s):  
Jean Béguinot
Keyword(s):  
Species Richness ◽  
Interspecific Competition ◽  
Species Abundance ◽  
Point Of View ◽  
Distribution Model ◽  
Conventional Measure ◽  
Species Abundances ◽  
Stick Model ◽  
Descriptive Purpose ◽  
Intensity Of Competition

A wide series of commonly used metrics of abundance-evenness (or -unevenness) have been proposed to characterize synthetically the distributions of species-abundances, accounting for the hierarchic-like organization of species within natural communities. Among them, most – if not all–have been relevantly criticized on their serious limitations regarding both their “descriptive” and their “interpretative” capacities. From the descriptive point of view, many authors have already repeatedly emphasized the formal non-independenceof conventional (un-)evenness metrics with respect to species-richness, leading, in particular, to unacceptable bias when comparing communities differing by their species-richness, thus making these metrics unreliable descriptors in this respect. Now, as regards the capacity to provide relevant ecological interpretations, especially in terms of the intensity of competition among co-occurring species, the weakness of conventional (un-)evenness metrics is readily highlighted by the usual absence of any associated interpretation of this kind in the literature: the conventional (un-)evenness metrics beingrestricted to purely descriptive purpose only. Accordingly, a newly designed abundance-unevenness metric – the “standardized abundance-unevenness” index is proposed, positively addressing both kinds of limitations evoked above. By standardizing a conventional measure,U,of abundance-unevenness to the corresponding measure, U’, of the abundance-unevenness in the well-known “broken-stick” model, the resulting “standardized unevenness” index (Istr = U/U’) proves to be efficient against both themajor limitations pointed-out above:indeed,the new index does benefit by being both (i) formally independent from species-richness, thereby allowing reliable,unbiased comparisons of abundance unevenness between species-communities, whatever their difference in species-richness; (ii) able to relevantly quantify the mean intensity of interspecific-competition within community, in term of its direct outcomeuponthe degree of species-abundance unevenness. This double success being, of course, the direct consequences of the properties of the “broken-stick” distribution model, originally putforth in a well-known, yet insufficiently thoroughly exploited paper by the regretted Robert MacArthur.

Species abundance, accumulation and diversity data.

2021 ◽  
pp. 200-217
Author(s):  
Donald L. J. Quicke ◽  
Buntika A. Butcher ◽  
Rachel A. Kruft Welton
Keyword(s):  
Species Richness ◽  
Papua New Guinea ◽  
Niche Partitioning ◽  
Species Abundance ◽  
Diversity Indices ◽  
Estimation Methods ◽  
Summary Statistics ◽  
Accumulation Curves ◽  
Global Patterns ◽  
Stick Model

Abstract Ecologists in particular are often interested in the species richness and diversity of groups of organisms, ranging from studies of small ecosystems to global patterns. In most cases it is not possible to count every individual or to detect every species, and so they use a variety of estimation methods and summary statistics that will be briefly introduce in this chapter. This chapter covers estimating species abundance and species richness by looking at accumulation curves. Analyzing diversity using tests such as the Shannon and Simpson diversity indices are also discussed. Finally, patterns of niche partitioning using the broken stick model are created. An example is shown, using transect surveys of butterflies in Papua New Guinea.

Species abundance, accumulation and diversity data.

2021 ◽  
pp. 200-217
Author(s):  
Donald L. J. Quicke ◽  
Buntika A. Butcher ◽  
Rachel A. Kruft Welton
Keyword(s):  
Species Richness ◽  
Papua New Guinea ◽  
Niche Partitioning ◽  
Species Abundance ◽  
Diversity Indices ◽  
Estimation Methods ◽  
Summary Statistics ◽  
Accumulation Curves ◽  
Global Patterns ◽  
Stick Model

Abstract Ecologists in particular are often interested in the species richness and diversity of groups of organisms, ranging from studies of small ecosystems to global patterns. In most cases it is not possible to count every individual or to detect every species, and so they use a variety of estimation methods and summary statistics that will be briefly introduce in this chapter. This chapter covers estimating species abundance and species richness by looking at accumulation curves. Analyzing diversity using tests such as the Shannon and Simpson diversity indices are also discussed. Finally, patterns of niche partitioning using the broken stick model are created. An example is shown, using transect surveys of butterflies in Papua New Guinea.

A Comparison of Three Sampling Gears for Capturing Aquatic Turtles in Missouri: The Environmental Variables Related to Species Richness and Diversity

2007 ◽  
Vol 41 (2007) ◽  
pp. 7-13 ◽  
Author(s):  
James E. Wallace ◽  
Zachary W. Fratto ◽  
Valerie A. Barko
Keyword(s):  
Species Richness ◽  
Dissolved Oxygen ◽  
Mississippi River ◽  
Species Abundance ◽  
Large River ◽  
Catch Per Unit Effort ◽  
Conservation Area ◽  
Turtle Species ◽  
Sternotherus Odoratus ◽  
Fyke Nets

Donaldson Point Conservation Area (DPCA) is a lentic area within the Mississippi River floodplain that experiences seasonal flooding because of direct connectivity to the Mississippi River. Sampling for aquatic turtles was conducted during fall (October–November 2003) and spring (April–May 2004) using fyke nets, hoop nets and basking traps in both round and linear pools. Hoop nets were deployed with and without the use of leads, whereas paired fyke nets were positioned with their leads tied together or straight from the bank. The performance of each net and the turtle species captured were assessed. Catch-per-unit effort (CPUE) when using hoop nets and fyke nets was considerably greater in fall than in spring. Fyke nets set perpendicular to the bank produced a CPUE greater than did the other gears deployed in the spring and fall. We captured eight turtle species: Trachemys scripta elegans, Graptemys pseudogeographica pseudogeographica, Alapone muticus muticus, Alapone spinifer spinifer, Sternotherus odoratus, Graptemys ouachitensis, Chrysemys picta dorsalis and Chelydra serpentina serpentina. Species richness was greater in areas with deeper water with low transparency, and lower in water with high dissolved oxygen and with greater depth of hoop net deployment. Species abundance was the lowest when hoop nets were deployed in linear water bodies with high turbidity, lower pH and low dissolved oxygen. Because turtle species are important biotic components of large river communities, protecting floodplain aquatic habitats such as those found within DPCA may help sustain large river turtle assemblages.

To the flora of сonjugates (Streptophyta, Conjugatophyceae) of the Valdai District area of the National Park «Valdaiskiy» (Novgorod Region, Russia)

2014 ◽  
Vol 48 ◽  
pp. 81-88
Author(s):  
A. F. Luknitskaya
Keyword(s):  
Species Distribution ◽  
National Park ◽  
Species Abundance ◽  
Water Bodies ◽  
Number Of Species ◽  
First Time

76 species, 3 varieties and 1 form from 21 genera of Streptophyta, Conjugatophyceae (Actinotaenium, Bambusina, Closterium, Cosmarium, Cylindrocystis, Euastrum, Gonatozygon, Haplotaenium, Micrasterias, Mougeotia, Netrium, Penium, Planotaenium, Pleurotaenium, Raphidiastrum, Spirogyra, Spirotaenia, Staurastrum, Staurodesmus, Tetmemorus, Xanthidium) were found in the basins of the Valdai District area of the National Park «Valdaiskiy» (Novgorod Region, Russia). The list of species is annotated with data on the species distribution in 55 collecting sites of 29 water bodies of the national park, and species abundance in collected samples according to Luknitskaya (2009). Among above mentioned genera, the genus Cosmarium is represented by the greatest number of species (20). Staurastrum chaetoceros has been found for the first time for the Novgorod Region.

scholarly journals Complex community responses underpin biodiversity change following invasion

2021 ◽  
Author(s):  
Alessandra R. Kortz ◽  
Anne E. Magurran
Keyword(s):  
Invasive Species ◽  
Species Richness ◽  
Spatial Scales ◽  
Species Abundance ◽  
Ecological Systems ◽  
Multi Scale ◽  
Mechanistic Approach ◽  
Α Diversity ◽  
Biodiversity Change ◽  
Insight Into

AbstractHow do invasive species change native biodiversity? One reason why this long-standing question remains challenging to answer could be because the main focus of the invasion literature has been on shifts in species richness (a measure of α-diversity). As the underlying components of community structure—intraspecific aggregation, interspecific density and the species abundance distribution (SAD)—are potentially impacted in different ways during invasion, trends in species richness provide only limited insight into the mechanisms leading to biodiversity change. In addition, these impacts can be manifested in distinct ways at different spatial scales. Here we take advantage of the new Measurement of Biodiversity (MoB) framework to reanalyse data collected in an invasion front in the Brazilian Cerrado biodiversity hotspot. We show that, by using the MoB multi-scale approach, we are able to link reductions in species richness in invaded sites to restructuring in the SAD. This restructuring takes the form of lower evenness in sites invaded by pines relative to sites without pines. Shifts in aggregation also occur. There is a clear signature of spatial scale in biodiversity change linked to the presence of an invasive species. These results demonstrate how the MoB approach can play an important role in helping invasion ecologists, field biologists and conservation managers move towards a more mechanistic approach to detecting and interpreting changes in ecological systems following invasion.

Diversity metrics, species turnovers and nestedness of bird assemblages in a deep karst sinkhole

2017 ◽  
Vol 63 (2) ◽  
pp. 8-16 ◽  
Author(s):  
Corrado Battisti ◽  
Marco Giardini ◽  
Francesca Marini ◽  
Lorena Di Rocco ◽  
Giuseppe Dodaro ◽  
...  
Keyword(s):  
Species Richness ◽  
Random Distribution ◽  
Diversity Index ◽  
Species Turnover ◽  
Floristic Composition ◽  
Bird Assemblages ◽  
Β Diversity ◽  
Stick Model ◽  
Karst Sinkhole

We reported a study on breeding birds occurring inside an 80 m-deep karst sinkhole, with the characterization of the assemblages recorded along its semi-vertical slopes from the upper edge until the bottom. The internal sides of the sinkhole have been vertically subdivided in four belts about 20 m high. The highest belt (at the upper edge of the cenote) showed the highest values in mean number of bird detections, mean and normalized species richness, and Shannon diversity index. The averaged values of number of detections and species richness significantly differ among belts. Species turnover (Cody’s β-diversity) was maximum between the highest belts. Whittaker plots showed a marked difference among assemblages shaping from broken-stick model to geometric series, and explicited a spatial progressive stress with a disruption in evenness towards the deepest belts. Bird assemblages evidenced a nested subset structure with deeper belts containing successive subsets of the species occurring in the upper belts. We hypothesize that, at least during the daytime in breeding season, the observed non-random distribution of species along the vertical stratification is likely due to (i) the progressive simplification both of the floristic composition and vegetation structure, and (ii) the paucity of sunlight as resources from the upper edge to the inner side of the cenote.

Designing a conservation area network that supports the representation and persistence of freshwater biodiversity

2010 ◽  
Vol 56 (1) ◽  
pp. 106-124 ◽  
Author(s):  
JEANNE L. NEL ◽  
BELINDA REYERS ◽  
DIRK J. ROUX ◽  
N. DEAN IMPSON ◽  
RICHARD M. COWLING
Keyword(s):  
Area Network ◽  
Freshwater Biodiversity ◽  
Conservation Area

scholarly journals Challenges for assessing vertebrate diversity in turbid Saharan water-bodies using environmental DNA

Genome ◽  
2018 ◽  
Vol 61 (11) ◽  
pp. 807-814 ◽  
Author(s):  
Bastian Egeter ◽  
Sara Peixoto ◽  
José C. Brito ◽  
Simon Jarman ◽  
Pamela Puppo ◽  
...  
Keyword(s):  
Environmental Dna ◽  
Water Bodies ◽  
Sampling Point ◽  
Sahara Desert ◽  
Turbid Water ◽  
Vertebrate Species ◽  
Sampling Protocol ◽  
Filtering Method ◽  
Small Water ◽  
Human Dna

The Sahara desert is the largest warm desert in the world and a poorly explored area. Small water-bodies occur across the desert and are crucial habitats for vertebrate biodiversity. Environmental DNA (eDNA) is a powerful tool for species detection and is being increasingly used to conduct biodiversity assessments. However, there are a number of difficulties with sampling eDNA from such turbid water-bodies and it is often not feasible to rely on electrical tools in remote desert environments. We trialled a manually powered filtering method in Mauritania, using pre-filtration to circumvent problems posed by turbid water in remote arid areas. From nine vertebrate species expected in the water-bodies, four were detected visually, two via metabarcoding, and one via both methods. Difficulties filtering turbid water led to severe constraints, limiting the sampling protocol to only one sampling point per study site, which alone may largely explain why many of the expected vertebrate species were not detected. The amplification of human DNA using general vertebrate primers is also likely to have contributed to the low number of taxa identified. Here we highlight a number of challenges that need to be overcome to successfully conduct metabarcoding eDNA studies for vertebrates in desert environments in Africa.

Do predaceous stoneflies and siltation affect the structure of stream insect communities colonizing enclosures?

1985 ◽  
Vol 63 (7) ◽  
pp. 1519-1530 ◽  
Author(s):  
Barbara L. Peckarsky
Keyword(s):  
New York ◽  
Species Richness ◽  
Prey Species ◽  
Species Abundance ◽  
Benthic Invertebrate ◽  
Taxonomic Composition ◽  
Community Response ◽  
Insect Communities ◽  
Composite Effect ◽  
Benthic Invertebrate Community

Experiments in Colorado and New York streams assessed the effects of predaceous stoneflies on benthic invertebrate community establishment in enclosures providing uncolonized habitat. Aspects of prey community structure measured were density, species richness, relative species abundance, and body size. Unexpected inorganic sediment deposition allowed evaluation of direct effects on Colorado stream benthos and indirect effects on predation. Predaceous perlids and perlodids consistently reduced the density and, therefore, rate of prey community establishment in enclosures. Although New York perlids disproportionately reduced densities of some prey species, Colorado stoneflies caused nonsignificant declines in individual prey species densities, the composite effect of which was a significant whole-community response. Predators did not affect prey species richness nor change the taxonomic composition (species additions or deletions) of communities colonizing enclosures. However, the relative abundance of prey taxa differed significantly between cages with and without predators. Most species showed no size differences between individuals colonizing enclosures with predators and those colonizing control enclosures, with a few interesting exceptions. The deposition of silt eliminated the predator effects on prey density, as well as directly causing significant reductions in many Colorado benthic populations. This result demonstrates that abiotic disturbances can periodically override the effects of predation on stream insect communities colonizing enclosures.

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