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Tóthmérész B.. Comparison of different methods for diversity ordering. J Veg Sci 6: 283-290
Abstract
The measurement of diversity, one of the most important concepts in present-day ecology, can be improved by methods of diversity ordering which have recently been developed. This ordering is achieved by a D(alpha)diversity index family. Indices of this family show varying sensitivities to the rare and abundant species as scale parameter, alpha changes. The aim of this paper is to review and assess 12 methods of diversity ordering and discuss their relationships in detail. Two of the methods are new to the ecological literature.
The diversity ordering methods are compared as to their effectiveness in graphically displaying the differences of community structure and demonstrating the (non)comparability of communities. Small, medium and large data sets were used to evaluate the methods. A small artificial data set (5-7 species) and a large artificial data set (31-141 species) are used in this paper.
The results suggest that Renyi's diversity index family and the Logarithmic dominance ordering are the most useful methods for diversity ordering of communities of all sizes. Right-tailed-sum diversity ordering performs well for small communities.
... However, single measures of α-diversity may sometimes fall short in fully capturing the complexity of a plant individual's chemical profile, or taking into account distinct effects of metabolite richness vs. dominant metabolites. In such cases, diversity profiles, such as the functional Hill diversity or Renyi profiles, offer a more nuanced approach towards measuring chemodiversity by considering metabolite abundances at different scales (Petrén et al., 2023, Tóthmérész, 1995. In addition, βdiversity refers to the variability in metabolite composition across space and time, generally in the form of intra-population variability, such as distinct "chemotypes" (refer section I.3.1), as well as the variability in metabolite induction (Metlen et al., 2009). ...
... These chemotypes showed increasing levels of Shannon diversity of their leaf terpenoids . In this chapter, we summarised their floral terpenoid chemodiversity with Renyi profiles (Tóthmérész, 1995) as well as richness and Shannon diversity indices. ...
... The terpenoid diversity of flower heads was analysed using Renyi diversity profiles based on Hα = ln (∑ pi α )/1−α, with α being a scale from 0 to infinity and p being relative abundance of each terpenoid within an individual, applying the function 'renyiresult' of the package biodiversityR (Kindt, 2005). Renyi profiles provide a range of diversity indices based on richness and proportional abundances (Tóthmérész, 1995). The scale parameter α is adjusted for different indices, with α = 0 related to richness, α = 1 related to the Shannon diversity index, α = 2 related to the Simpson diversity index, and α = infinity for the Berger-Parker index (Tóthmérész, 1995). ...
Plants produce a multitude of specialised metabolites in order to interact with their biotic and abiotic environment. Several of these compounds are defensive towards antagonists, such as herbivores and pathogens. Simultaneously, plants may use specialised metabolites to attract mutualists like pollinators and symbionts. These metabolites vary pronouncedly in their qualitative and quantitative composition not just among species, but also between plant parts (organs), individuals and populations within species, giving rise to chemical diversity, i.e., chemodiversity. The importance of chemodiversity, particularly intraspecific chemodiversity, has been mostly explored for vegetative plant parts such as leaves and roots, but very little is known about its role in reproductive organs, namely, flowers. Outcrossing flowers face a challenging dilemma in their biotic interactions, i.e., they must simultaneously attract pollinators, essential for reproductive success, while repelling floral herbivores (florivores), which cause damage, using the same chemical blend. Since both pollinators and florivores evolved towards floral signals, they may perceive and use the same cues for visiting flowers and may be similarly affected by attractive and defensive floral chemicals. Plants must find strategies to overcome such trade-offs in the attraction and repellence of both visitor groups using their floral chemodiversity. The importance of floral chemodiversity towards these different groups and in navigating trade-offs within this conflict has not been previously explored. Furthermore, little was known about the significance of different levels of chemodiversity as well as its potential informational role towards flower visitors.
This thesis aimed to investigate and thereby understand the role of intraspecific plant chemodiversity with a focus on floral interactions with pollinators and florivores. I also explored the potential trade-offs that might emerge for the plant within these interactions, and how chemodiversity may contribute to shaping or overcoming these trade-offs. Using a meta-analysis, I compiled previous studies that assessed floral chemical displays including floral volatiles, toxins and nutrients. I summarised the literature highlighting the significance of these displays in pollinator and florivore interactions and how chemodiversity within these displays correlate to one another. Furthermore, using a highly chemodiverse Asteraceae plant study system, Tanacetum vulgare, and associated pollinator and florivore species, I investigated the role of intraspecific chemodiversity in flower interactions with insect visitors. I applied various approaches to address this topic, including chemical analyses of targeted metabolites, laboratory and greenhouse bioassays and complex statistical tools such as multivariate and generalised (linear) regression analyses. Moreover, a long-term common garden experiment enabled me to explore the complex ecological interactions occurring within a field setting and how intraspecific chemodiversity at different levels might shape them.
In Chapter II, I used a combinatorial approach to summarise earlier studies, a comprehensive review of existing literature coupled with two distinct meta-analyses, in order to describe the diversity and complexity of floral chemical displays. I investigated how pollinators and florivores differ in their perception and behaviour towards floral displays. Synthesising current knowledge, I placed an emphasis on potential sources for trade-offs for flowers within pollinator and florivore interactions, shaped by floral chemical cues. This review highlighted the dearth of studies on florivory, unravelling a gap that may potentially lead to a biased understanding of these processes. In the two meta-analyses, I addressed firstly whether the responses to floral volatiles differ between pollinators and florivores across a range of plant species. I uncovered, based on existing literature for seven plant genera, that florivores may be able to detect more floral volatiles than pollinators. Pollinators and florivores were found to be more commonly attracted, rather than repelled, to the same floral volatiles. Secondly, I investigated whether there is a link between the chemodiversity of floral volatiles and the toxins and nutrients of pollen, a key floral reward. Floral volatile richness and that of pollen toxins were negatively correlated, whereas volatile richness and pollen protein content were marginally positively correlated. Thus, floral volatile diversity is potentially informative of reward traits, with florivores evidently being able to detect a larger portion of this chemodiversity, leading to potential trade-offs for insect-pollinated plants.
In Chapter III, I used an artificial pollination experiment to study the influence of pollination on intraspecific floral chemodiversity of T. vulgare and vice-versa in a greenhouse setting. T. vulgare shows distinct chemical phenotypes called chemotypes that differ in compositions of terpenoids, their predominant specialised metabolites. Floral volatile, terpenoid, sugar and organic acid composition was analysed in flower heads from three chemotypes, with or without prior artificial pollination of the flower heads. Using multivariate statistics, I determined that these compositions were all dependent on the chemotype but not on the pollination status. I further investigated whether chemodiversity has an influence on pollinators using bioassays with the bumblebee Bombus terrestis, a generalist pollinator of T. vulgare. The preferences of bumblebees depended on the chemotype; specifically, the low-diversity chemotype was least preferred among the three chemotypes. These results highlight the impact of intraspecific chemodiversity on pollination, but also suggest that pollination does not necessarily alter floral chemistry or chemodiversity.
In Chapter IV, I used the same chemotypes as used in Chapter III to examine the influence of intraspecific floral chemodiversity on a florivore species of T. vulgare under laboratory conditions. Analytical platforms were implemented to determine the chemical composition of terpenoids and nutrients of flower heads and pollen from plants belonging to the three chemotypes, to obtain a comprehensive picture of the primary and specialised metabolites that form the chemical variation within these chemotypes. Multivariate statistical analyses revealed that terpenoid composition and chemodiversity of flower heads and pollen significantly differ among individuals belonging to the above chemotypes, while total concentrations of pollen terpenoids, sugars, amino acids, and lipids did not differ between chemotypes. Furthermore, in preference and performance assays with the florivorous beetle species Olibrus aeneus, I determined that flower heads of the high richness, low Shannon-diversity chemotype was preferred the most and resulted in highest feeding and survival of the beetles relative to the other two chemotypes. These results demonstrated that florivores can be influenced by intraspecific floral chemodiversity, which was attributed here to specialised metabolite diversity rather than that of nutritional differences. Different measures of chemodiversity, such as richness and overall evenness-based diversity, may be relevant towards distinct functions within biotic interactions of plants.
In Chapter V, I studied the influence of different levels of chemodiversity on pollinator and florivore visitation and subsequent effects on plant fitness under semi-field conditions. This was done within a common garden consisting of homogeneous (same chemotype plants) and heterogeneous (different chemotype plants) plots with five plants each. Ten plots were present in six blocks and plants and plots were arranged in a balanced design. Flower visitors were observed regularly and seeds were collected at the end of the flowering season for germination analyses to determine a proxy of plant fitness. The experiment was replicated for a second year without the germination assay. Generalised linear modelling was performed to discern the role of chemotype and plot type in influencing visitor groups and effects on plant fitness. I found that heterogeneous plots and one of the chemotypes in interaction with homogeneous plots had a higher number of pollinator visits. However, chemotype but not plot type influenced florivore visits. The observed effects on flower visitors within a plot type were not due to differences in visitor species richness between the types. Pollinators and florivores competed with each other, in dependence of floral resources, but also averting potential trade-offs for flowers in attracting both visitor groups. Germination success of plants was influenced by chemotype and pollinator visits, but not directly by plot type. Chemodiversity at different levels may thus have differential effects on pollinators and florivores, with consequent direct or indirect effects on plant fitness.
In conclusion (Chapter VI), this thesis emphasises that chemodiversity at different levels is relevant towards pollinator and florivore activity and must be considered in terms of both qualitative (richness) and quantitative (proportional abundances) measures of metabolites. The synthesis of knowledge from the review and meta-analyses implicates the potential for trade-offs in plants due to sharing of signals that both visitor groups depend on for the discovery of floral resources. The results from the empirical studies with T. vulgare suggest that plants may utilise intraspecific chemodiversity to avoid trade-offs in attracting both mutualists and antagonists, through complex interactions at the individual and neighbourhood (plot) level. The methods established in the thesis may be transferred to other plant and insect study systems with minor modifications. With the results generated from this thesis, I provide suggestions towards a more holistic understanding of plant chemodiversity within all plant-flower visitor systems. Particularly, using multiple measures for chemodiversity, studying it across different scales and applying integrated approaches are methodologies that may be universally applied.
... The natural value of seminatural meadows is often assessed based on such indices as species richness, the presence of rare species, or different indices, e.g., Shannon-Wiener, Simpson, Margaleff, Pielou, etc. (Shannon and Weaver, 1963;Pielou, 1975;Simpson, 1949;Margalef, 1958;Bandeira et al., 2013). Generalized indices have also been proposed, such as those of Renyi, Tsallis, Hurlbert, Daróczy, Patil, Taillie, and others (Hill, 1973;Tóthmérész, 1995), which allow for a more comprehensive interpretation of differences in species composition. ...
... Two types of generalized diversity indices, also called Renyi and Tsallis series (Hill, 1973;Tóthmérész, 1995), were used to analyse floristic diversity. These generalized indices define so-called diversity profiles, which allow for a better and more visual assessment of the floristic diversity of plant communities than commonly used indices such as richness, Shannon-Wiener index, Simpson index, or evenness. ...
... . What is closely related to the Renyi coefficients is the Hill numbers (Hill, 1973) defined by the formula H a = exp(R a ). In turn, Tsallis generalized diversity indices are calculated from the formula (Tóthmérész, 1995): ...
The objectives of our research were: (1) to assess the influence of the frequency of mowing different types of seminatural meadows characteristic of Central Europe on their floristic diversity, (2) to indicate the optimalmanagement method (3) to estimate changes in species richness of phytophagous beetles from the Chrysomelidaefamily under the influence of mowing, against the background of different types of meadows.
Studies conducted in a single Natura 2000 site (The Middle Wieprz Valley PLH060005) in eastern Poland haveshown that mowing frequency affects both the flora and fauna diversity of seminatural meadows typical ofCentral and Eastern Europe. The greatest alpha-diversity was found in double-mow meadows, while the least wasfound in the unmown ones. Therefore, double-mowing of meadows could be a recommendation for agri-environment-climate programs that support environmentally friendly farming methods in the EuropeanUnion. The Renyi diversity profiles made it possible to observe differences resulting from the frequency ofmowing, especially in relation to single-mow meadows. Wet meadows (Molinietalia) and mixed meadows(Molinio-Arrhenatheretea) had similar characteristics, both in the case of single and double mowing, with a moreuniform coverage of species.
The least floristic diversity, expressed in species richness, was characteristic of rush meadows, while thelargest was of fresh meadows. The greatest decline in chrysomelid beetle species richness was observed in rushand wet meadows, while an increase was observed in fresh meadows. Higher-order indices are easier to interpretwhen expressed in Renyi series. The assessment could also apply to ecosystems other than grasslands. Due to thedifferences obtained in the values of individual orders, it is more advantageous to use Renyi indices, especiallywhen it comes to interpreting the occurrence of dominant species in the community. Only in the case of freshmeadows, a simultaneous increase in the alpha and beta-diversity coincided with a higher frequency of mowing.In the case of the other meadow types, with an increase in mowing frequency, higher diversity but lower beta-diversity was found.
... To graphically compare diversities in several samples, we used the diversity profile models [22]. Diversity profiles have been used because the validity of comparing diversities across samples can be criticized because of the arbitrary choice of a diversity index. ...
... In this regard, a number of diversity indices may be compared to make sure that the diversity ordering is robust. A formal way of doing this is to define a family of diversity indices, dependent upon a single continuous parameter [22]. We used the exponential of the socalled Renyi index, which depends upon a parameter α on the x-axis. ...
... We used the exponential of the socalled Renyi index, which depends upon a parameter α on the x-axis. For α = 0, this function gives the total species number, α = 1 gives an index proportional to the Shannon index, while α = 2 gives an index which behaves like the Simpson index [22,23]. The bootstrapping option (giving a 95% confidence interval) was based on 2000 replicates. ...
In many tropical areas of high conservation concern there is still no evidence on the
effectiveness of protected areas in protecting specific components of biodiversity. Here, to assess the management effectiveness of protected areas, we carried out a field sampling design for collecting data on waterbird communities within the Nibule National Park (South Sudan), a poorly-known hot-spot of biodiversity, and in the surrounding buffer zone. All the metrics of richness (absolute species richness, Margalef index, Chao-1) and diversity were significantly higher for bird communities
inhabiting the national park, when compared to the buffer zone. Evenness was predictably lower in the national park when compared to the buffer zone, probably due to the large numbers of rare species that were observed in the park’s richer communities, thus increasing the differences in relative frequencies between species. The diversity profiles highlighted this pattern, with more sloping
curves in the park sites, evidencing a role of protected area management in positively affecting the bird community structure. Our data provide the first evidence for a poorly-known area of high conservation concern on the effective role played by a National Park in maintaining high values of richness and diversity, at least for wetland-related birds.
... To compare diversity of plots, seasons and years, we used Rényi's diversity profiles from the diversity module of PAST [36,37]. The most common diversity indices have different sensitivities, e.g., the Shannon index is sensitive to the number of taxas, while the Simpson index measures the evenness [36]. ...
... The most common diversity indices have different sensitivities, e.g., the Shannon index is sensitive to the number of taxas, while the Simpson index measures the evenness [36]. To avoid arbitrary choice of diversity indices, Rényi's diversity profiles, as a single continuous parameter-based method, provided a formal way [37] to compare our plots' diversity. The result graph contained profiles which made the diversity of different plots comparable if they were not crossing each other [36]. ...
Asclepias syriaca L.is a perennial broad-leaved species native to North America. It has become established in many regions of Europe, and has spread with increasing rapidity in recent decades. Its reproductive behaviour allows this species to proliferate rapidly. The selected grasslands are located in the Carpathian Basin in Hungary, in the area of Kiskunság National Park, near Lake Kolon. In the framework of the research, in two consecutive years (2021 and 2022), and in two different seasons (spring and autumn), we examined the percentage cover of vascular plant species in the stands degraded by A. syriaca and the natural control (without A. syriaca), and their seasonal and interannual dynamics. Between the A. syriaca-degraded and natural control stands, there was no significant difference in the number of species in the spring and autumn of any of the examined years. Surprisingly, in the spring, the degraded stands were somewhat richer in vascular plant species. In autumn, the control stands had more vascular plant species, but to a lesser extent. The Shannon diversity was higher in the A. syriaca-dominated stands than in the control in all recording periods. Simpson diversity showed a similar pattern to Shannon diversity, with one exception in spring 2022. In the case of the social behaviour type, it can be clearly seen that the alien competitor (AC) species dominated in spring and autumn in both years in the stand dominated by A. syriaca. In the natural control stand, specialists (S) and competitors (C) dominated in both years and in both seasons. The negative effect of the invasive species on the number and diversity of species was presumably significantly reduced by the significant drying of the study area experienced in recent years.
... La diversidad temporal fue comparada con los perfiles de diversidad de Renyi de cada evaluación. Estos perfiles muestran gráficamente las principales familias de índices de diversidad ordenadas según su sensibilidad a las especies raras hasta las dominantes mediante el parámetro α, los cuales tienen relación con los principales índices de diversidad como la riqueza (parámetro α = 0), Shannon (parámetro α = 1) y Simpson (parámetro α = 2), y permite una comparación visual del comportamiento de las diversidades de acuerdo al mencionado parámetro α (Tóthmérész, 1995;Hammer, 2019). La diversidad espacio-temporal fue analizada por la relación del promedio del índice de diversidad Inversa de Simpson y su coeficiente de variación temporal de todos los transectos, modificando el método de Véliz et al. (2002), al reemplazar el índice de Shannon-Wiener. ...
... Las especies con más IARE promedio en todas las evaluaciones fueron Zonotrichia capensis y Geospizopsis plebejus, con 0.5726 ind/100 m y 0.5620 ind/100 m por evaluación, respectivamente (Tabla 1). Análisis de patrones temporales La diversidad temporal no presentó diferencias entre las cuatro evaluaciones debido al entrecruzamiento de los perfiles de diversidad (Tóthmérész, 1995), aunque existió una tendencia de mayor diversidad por las especies raras (α = 0) y por dominancia de especies (α = 2) en las épocas secas y lluviosas, respectivamente (Figura 2). La diversidad por dominancia es explicada por las altas abundancias relativas de individuos juveniles y adultos de especies gregarias en las épocas secas que afectan inversamente en los valores de diversidad. ...
The interpretation of biological communities as complex adaptive systems aims to demonstrate their ecological patterns at different scales and their environmental relationships. In this survey, we analyzed species diversity and alternative stable states patterns of the bird community in an Andean agroecosystem located on the central-western slope of the Peruvian Andes (Cajatambo District, Lima - Peru), on a temporal and spatio-temporal scale. We evaluated their bird community through 24 line transects, located in seven plant formations along two ecoregions, between 2 700 and 4 600 masl, during the dry and rainy seasons of 2015 and 2016. The temporal patterns did not show differences in species diversity between seasons. We determined the existence of a single temporary alternative stable states; however, we evidenced changes in their species composition between dry and rainy seasons, suggesting a greater functional redundancy in dry season than rainy season due to temporal variability of small granivore-insectivore species. Regarding the spatio-temporal patterns, the plant formations of Polylepis forests, some scrubs and agricultural lands presented high values of species diversity. In addition, we determined eight alternative stable states in relation to one or more plant formations and seasonality. Finally, a higher proportion of regime changes was found in the community alternative stable states located in the Meso-Andean ecoregion as opposed to the Puna-Humid ecoregion, which would suggest that this bird community has a greater self- organization and adaptability in the face of environmental stochasticity.
... La diversidad temporal fue comparada con los perfiles de diversidad de Renyi de cada evaluación. Estos perfiles muestran gráficamente las principales familias de índices de diversidad ordenadas según su sensibilidad a las especies raras hasta las dominantes mediante el parámetro α, los cuales tienen relación con los principales índices de diversidad como la riqueza (parámetro α = 0), Shannon (parámetro α = 1) y Simpson (parámetro α = 2), y permite una comparación visual del comportamiento de las diversidades de acuerdo al mencionado parámetro α (Tóthmérész, 1995;Hammer, 2019). La diversidad espacio-temporal fue analizada por la relación del promedio del índice de diversidad Inversa de Simpson y su coeficiente de variación temporal de todos los transectos, modificando el método de Véliz et al. (2002), al reemplazar el índice de Shannon-Wiener. ...
... Las especies con más IARE promedio en todas las evaluaciones fueron Zonotrichia capensis y Geospizopsis plebejus, con 0.5726 ind/100 m y 0.5620 ind/100 m por evaluación, respectivamente (Tabla 1). Análisis de patrones temporales La diversidad temporal no presentó diferencias entre las cuatro evaluaciones debido al entrecruzamiento de los perfiles de diversidad (Tóthmérész, 1995), aunque existió una tendencia de mayor diversidad por las especies raras (α = 0) y por dominancia de especies (α = 2) en las épocas secas y lluviosas, respectivamente (Figura 2). La diversidad por dominancia es explicada por las altas abundancias relativas de individuos juveniles y adultos de especies gregarias en las épocas secas que afectan inversamente en los valores de diversidad. ...
La interpretación de las comunidades biológicas como sistemas complejos adaptativos, pretende evidenciar sus patrones ecológicos a diferentes escalas y sus relaciones ambientales. En este trabajo se analizaron los patrones de diversidad de especies y de los estados alternativos de la comunidad de aves en un agroecosistema andino ubicado en la vertiente centro-occidental de los Andes peruanos (Distrito de Cajatambo, Lima-Perú), a una escala temporal y espacio temporal. Durante los años 2015 y 2016 se realizaron 24 transectos, ubicados en siete formaciones vegetales a lo largo de dos ecorregiones, entre 2 700 y 4 600 msnm, abarcando las épocas secas y lluviosas. Los patrones temporales no mostraron diferencias en la diversidad de especies entre las épocas. Se determinó la existencia de un solo estado alternativo temporal; sin embargo, se evidenciaron cambios en su composición de especies entre épocas lluviosas y secas, sugiriendo una mayor redundancia funcional en la época seca que la época lluviosa por la variabilidad temporal de granívoros-insectívoros pequeños. Con respecto a los patrones espacio-temporales, las formaciones vegetales de bosques de Polylepis (queñual), algunos matorrales y campos agrícolas presentaron altos valores de diversidad de especies. Además, se determinaron ocho estados alternativos asociados a una o más formaciones vegetales y a la estacionalidad. Finalmente, se evidenció una mayor proporción de cambios de regímenes de los estados alternativos comunitarios ubicados en la ecorregión Meso-Andina a diferencia de la ecorregión Puna-Húmeda, lo cual sugiere que estas comunidades de aves poseen una mayor autoorganización y adaptabilidad frente a la estocasticidad ambiental.
... Variation in dung beetle species composition with the dung type was determined using three approaches implemented using PAST statistical software (Hammer et al., 2001). First generalised Rényi entropy expressed as Rényi diversity, HR (a) (Lövei et al., 2002;Tóthmérész, 1995), was calculated across the dung types as follows: ...
... where p i is the relative abundance of the ith species, and S is the number of species; and a is the scale parameter. The result was then represented graphically to see how the diversity profiles of the community changes with the scale parameter as the emphasis shifts from rare to common species (Tóthmérész, 1995). Second, because the diversity profiles curves may sometimes overlap and obscure differences between species composition of the different dung types, a non-metric multidimensional scaling (NMDS), an ordination technique that assembles similar groups together, was performed using PAST software (Hammer et al., 2001). ...
Few studies have examined how dung beetle species composition changes across several mammalian dung types. Species composition and abundance of dung beetles were studied in dung samples of seven African mammals along animal trails and using 14 baited‐pitfall traps in both the park and the buffer zone resulting in a combined data set of 113 samples. Both the number of species (18) and the number of individual dung beetles (600) encountered were low for an area close to the Equator. Few species (2) and herbivores (13) tunnellers (9) dominated the dung beetles community, feeding and guild structure respectively. Alpha diversity was moderate 2.06 (1 < H′ ≤ 3). Beta diversity ranged from low 0.8 (high similarity) to high (zero, no similarity). Dung beetle species composition varied with dung type with the degree of pairwise similarity between two dung types in 19 of the total (21) dung beetle communities comparisons showing low similarity (0.4) to no similarity (zero). The observed discrepancies may be attributed to dung size, composition and consistency as well as to the low number of dung of the different animal species sampled. Furthermore, further research is needed as rarefaction curves suggest that sampling was incomplete.
... The diversity of lapidary production in the archaeological sites (characterized by different numbers of artifacts, types, raw materials) is evaluated following ecological methods of quantification. Diversity is calculated for different scales, giving more or less weight to rare mineral species (Tóthmérész, 1995;Marcon, 2018). This use of parametric families of diversity, instead of classical diversity indices, avoids the inconsistencies sometimes observed when trying to reduce the complexity of a multidimensional entity to a single number (Tóthmérész, 1995), for example with the richness index which is strongly impacted by the sample size (Kintigh, 1984;Shott, 2010). ...
... Diversity is calculated for different scales, giving more or less weight to rare mineral species (Tóthmérész, 1995;Marcon, 2018). This use of parametric families of diversity, instead of classical diversity indices, avoids the inconsistencies sometimes observed when trying to reduce the complexity of a multidimensional entity to a single number (Tóthmérész, 1995), for example with the richness index which is strongly impacted by the sample size (Kintigh, 1984;Shott, 2010). In this method, diversity of scale q is noted q D. 0 D is species richness (the number of species), 1 D is directly related to the Shannon index of diversity [ 1 D = exp(Shannon index)], while 2 D is a value of diversity less sensitive to the rare species and equivalent to the Simpson index (Hill, 1973). ...
Personal ornaments, and especially those made of lithic materials, are an important part of the archaeological record, as they provide valuable insights into various aspects of past human societies. In the Caribbean islands’ Ceramic Age, lapidary artifacts exhibit remarkable abundance and diversity in terms of both raw materials and typology. Robust analysis of extensive datasets enables to address the questions of spatial and temporal distribution and diversity of lithic beads and pendants during this period. I demonstrate that the Early and Middle Ceramic periods exhibit higher raw material and typological diversity compared to later periods. Mineralogical and typological similarities are shown to be greater between sites attributed to the same period than between geographically close sites. The lapidary production during the Saladoid differs significantly between the continent and the archipelago. Some indications pointing to the Isthmo-Colombian area are proposed, which will require further research to enhance our understanding to the same level as that of the Caribbean islands, enabling advanced comparisons.
... The Rényi diversity method was used to emphases the characteristics and distinctions of the three communities studied and compare their diversity levels (Tóthmérész, 1995). The generated curves were an easy way to reduce the complexity of species structures in relevés and compare their level of diversity (Loreau et al., 2002;Tóthmérész, 1995), as a complement to the assessed diversity indices (Species richness, Shannon and Evennes, Table 2). ...
... The Rényi diversity method was used to emphases the characteristics and distinctions of the three communities studied and compare their diversity levels (Tóthmérész, 1995). The generated curves were an easy way to reduce the complexity of species structures in relevés and compare their level of diversity (Loreau et al., 2002;Tóthmérész, 1995), as a complement to the assessed diversity indices (Species richness, Shannon and Evennes, Table 2). Analogous to Kindt et al. (2006), we evaluated this method as effective because it considers a wider range of diversity measures, rather than relying on a single index like Shannon or Simpson (Loreau et al., 2002). ...
Riparian woody plant communities, including shrubs and trees, are essential for maintaining biodiversity, protecting against floods, reducing erosion, and transporting nutrients. However, these habitats are greatly threatened by human activities, particularly agricultural land acquisition, and the introduction of invasive species. This study examined species diversity and interspecific association in riparian woody plant communities along rivers in the Romanian Carpathians. The study focused on communities of Salix purpurea, S. alba, and Hippophaë rhamnoides in mountain regions, with varying sampling efforts at different sites for each species. A total of 174 plant species were found, predominantly herbaceous (77.9%), followed by trees (11.6%) and shrubs (10.5%). While S. alba and S. purpurea communities show high species richness and abundance, S. alba has slightly higher diversity (H′ ≈ 2.23, SD = 0.28) than S. purpurea (H′ ≈ 1.69, SD = 0.42). Contrarily, significant differences exist between H. rhamnoides and S. alba communities in species richness (p = .007) and Shannon diversity (p = .004). PCA analysis elaborated on distinct distribution patterns of plant associations within habitats S. purpurea community, H. rhamnoides community, and S. alba community. Four invasive species (Oenothera biennis L. and Oxalis stricta L. in S. alba communities, Reynoutria sachalinensis Nakai in both S. purpurea and H. rhamnoides communities, and Erigeron canadensis L. in H. rhamnoides communities) were identified, as requiring conservation efforts. Hemicryptophytes dominate species richness, while microphanerophytes and megaphanerophytes significantly contribute to plant abundance. H. rhamnoides formed Hippophaë rhamnoides dunes (2160) Natura 2000 habitat, while S. alba created galleries within the 92A0 Salix alba and Populus alba habitat. In conclusion, the findings from this study highlight the importance of preserving riparian habitats because their value goes beyond local or regional considerations and extends to the global scale due to their unique characteristics.
... Using Origin software, the species relationships between forest types were visualized using Principal Component Analysis (PCA) Haq et al., 2022c). To highlight differences in curves for sampling forest locations, the Renyi diversity profile (Tóthmérész, 1995;Dejene et al., 2017) was utilized. A Venn diagram was generated using Bioinformatics & Evolutionary Genomics software to emphasize the differences and unique species among forest types (Altaf et al., 2021). ...
... The exotic weedy herbaceous plant species were Poa annua, Mentha longifolia, Erigeron acer, Digitalis purpurea, and Urtica dioica, growing in the forest ecosystems of the study area. Such alien weedy plants have also been observed in the woods of other Himalayan locations (Koul et al., 2015;Haq et al., 2019a;b). Initial forest invasions may promote species invasions by creating conditions that favor newcomer invasive species over native species, allowing biological invasions to develop (Haq et al., 2021a,b). ...
Concise efforts are required to manage forest ecosystems to achieve the global goals envisioned for the UN Decade (2021–2030) of Ecosystem Restoration targets. Among various global drivers of forest degradation, anthropogenic stresses may contribute to the long-persisting impact on vegetation dynamics and are one of the major impediments to the successful restoration of forest ecosystems at the local and regional scales. The research was focused on elucidating how anthropogenic disturbances influenced the forest composition, diversity, and phytosociological attributes of high-elevation forests of the Himalayas. Based on the intensity of anthropogenic stress and location, three differently disturbed sites i.e., Severely Disturbed (SD), Moderately Disturbed (MD), and Low Disturbed (LD) forest sites were selected. A random sampling method was used to record the vegetation parameters of the forest stands. Multivariate PAST software ver. 3.14 was employed to observe the relationship between ecological variables and plant communities. The results showed significant differences in vegetation composition between the forest types. Data collected revealed that composition, diversity, and phytosociological attributes (basal area) were decreased with the increase of anthropogenic stress. SD forest sites exhibited (3.1) times more deforestation rate than MD site (2.08) and declined with decreasing disturbance levels. Anthropogenic stress affected vegetation patterns and associations among plant communities, according to the Principal Component Analysis ordination. The study's findings generated empirical data that could be used to guide the restoration of degraded ecosystems to meet global goals as well as the UN Decade of Ecosystem Restoration targets (2021–2030) for forest management and the sustainable development of mountainous regions
... With Hill numbers, species are weighed in proportion to their frequency (i.e., the number of species in the assemblage). Computation of diversity profile values (H-alpha) were done from the frequencies of each species (proportional abundances pi = abundance of species i/ total abundance) and a scale parameter (α) ranging from zero to infinity, as shown in Eq. 1: (Tóthmérész 1995). ...
Fruits species incorporation in cocoa farms is characteristic of tropical cocoa agroforestry systems. This study assessed fruit species composition and diversity in eight age classes (C) of cocoa agroforests (CAFs). Fruit species were inventoried on 72 (100 × 100 m) plots among eight CAF age classes—C1 (1–5 years), C2 (6–10), C3 (11–15), C4 (16–20), C5 (21–25), C6 (26–30), C7 (31–35), C8 (36–40 years)—within three communities. Fruit species abundance, richness and diversity were estimated using Broken Stick model, Chao-1 model and Hill numbers respectively. A total of 445 individuals, 11 species and 8 families were recorded over a 72 ha area. Species abundances differed significantly ((F = 9.84, df = 26.5, p = 5.273E-06; Welch’s F test) among the age classes. Majority of species (78.4%) were introduced as new plants into the CAFs and were dominantly P. americana (n = 117), Citrus spp. (n = 82), C. nucifera (n = 74) and Musa spp. (n = 71) while A. occidentale (n = 2) was the least. Diversity was highest for C2 and least for C1. Chao-1 estimate showed that C5 was richest in fruit species, while C8 was the poorest. The presence of rare indigenous species (Synsepalum dulcificum and Chrysophyllum albidum) shows that fruit species management in CAFs alter vegetation composition but still contribute to biodiversity conservation goals in agricultural landscapes. Further research that relates fruit species diversity or abundances to cocoa productivity, soil properties and carbon sequestration is recommended.
... Correlation between the frequency and abundance of identified prey items was analyzed using Spearman's rank correlation coefficient (Rho). The comparison of sexes in terms of diet diversity was carried out using Rényi's index family (diversity profiles), which has been considered one of the most useful methods for ordering samples according to their diversity (Tóthmérész 1995). Regarding prey evasiveness and hardness, the comparisons between males and females were done by Chi-square (χ 2 ) test. ...
The snake-eyed skink (Ablepharus kitaibelii) is one of the smallest European lizards and is still insufficiently studied, especially in regard to its trophic preferences. We studied a total of 100 individual faecal samples of A. kitaibelii from two sites in Western Bulgaria and collected information for the potential trophic resource (using pit-fall traps). The results showed that Araneae and Auchenorrhyncha have the largest relative share in the trophic spectrum of the species, which, to some extent, confirms what was found in previous studies. The presence of five higher taxa of invertebrates (Gastropoda, Acari, Blattodea, Orthoptera and Rhaphidioptera) in the diet of A. kitaibelii was recorded for the first time. Several cases of keratophagy (a phenomenon that has not been reported for this species) were also recorded. Regarding the main physical characteristics of the prey (evasiveness and hardness), it was found that A. kitaibelii prefers sedentary and medium moving prey regardless of its hardness. We found no differences between sexes in food preferences.
... These tests were used to assess bacterial community composition variation between samples with sufficient replicates. Alpha diversity was evaluated as Hill numbers (Hill, 1973;Kindt et al., 2006;Tóthmérész, 1995) with the reyni function from the vegan package. Venn diagrams were created using Eulerr packages (version 7.0.2). ...
... Correlation between the frequency and abundance of identified prey items was analyzed using Spearman's rank correlation coefficient (Rho). The comparison of sexes in terms of diet diversity was carried out using Rényi's index family (diversity profiles), which has been considered one of the most useful methods for ordering samples according to their diversity (Tóthmérész 1995). Regarding prey evasiveness and hardness, the comparisons between males and females were done by Chi-square (χ 2 ) test. ...
The snake-eyed skink (Ablepharus kitaibelii) is one of the smallest European lizards and is still insufficiently studied, especially in regard to its trophic preferences. We studied a total of 100 individual faecal samples of A. kitaibelii from two sites in Western Bulgaria and collected information for the potential trophic resource (using pitfall traps). The results showed that Araneae and Auchenorrhyncha have the largest relative share in the trophic spectrum of the species, which, to some extent, confirms what was found in previous studies. The presence of five higher taxa of invertebrates (Gastropoda, Acari, Blattodea, Orthoptera and Rhaphidioptera) in the diet of A. kitaibelii was recorded for the first time. Several cases of keratophagy (a phenomenon that has not been reported for this species) were also recorded. Regarding the main physical characteristics of the prey (evasiveness and hardness), it was found that A. kitaibelii prefers sedentary and medium moving prey regardless of its hardness. We found no differences between sexes in food preferences.
... function before running PERMANOVA or pairwise PERMANOVA tests. Rényi diversity profiles were used to compare diversity between the locations and farms sampled, as they allow for direct comparison of common diversity metrics in addition to being generally accepted as one of the more useful methods [35]. Rényi diversity profiles were obtained through the renyicomp function from the BiodiversityR package (version 2.16.1), using 1000 permutations with the smallest sample size among compared categories to determine margins of error and testing at α = 0, 0.25, 0.5, 1, 2, 4, 8, and infinity [36]. ...
Agricultural drainage ditches contain a variety of non-crop vegetation, including potential sources of alternate hosts and food for hymenopteran parasitoids that provide conservation biological control on adjacent farm fields. To assess the patterns of family-level diversity of hymenopteran parasitoids, we surveyed ditch and adjacent crop habitats during June, July, and August 2021–2023, using yellow sticky traps over one week. We sampled two agricultural drainage ditches on each of five farms on the Delmarva Peninsula, eastern USA. We collected 36,725 specimens and identified 29 families across 738 sticky traps. Parasitoid diversity was greater in agricultural ditches than in adjacent fields. While parasitoid family diversity and abundance varied across the farms, ditches within a farm were similar. Within crop fields, diversity was greater at 1.5 m from agricultural ditches than at 9.1 m from the ditches. For several well-sampled families, greater abundance on one farm relative to others extended to both ditches and adjacent crops. Our findings indicate that agricultural drainage ditches serve as an existing beneficial semi-natural habitat for parasitoids on farms. Further research into ditch management practices may reveal methods of enhancing parasitoid abundance and conservation biological control while requiring relatively little investment from farm managers.
... This analysis was done with the `renyi´ function (hill = TRUE) in the vegan package (Oksanen et al. 2018) in R. Therefore, Hill's diversity profile helps in inferring how and which mite community is more diverse than another, in this case, dry vs. rainy. In the parameters of this scale (x-axis), the values on the left side are sensitive to rare species, while the values on the right side are sensitive to abundant, common species (Tóthmérész 1995). ...
This study aimed to understand the diversity of associated mites in cocoa growing areas in the municipalities of Bragança and Augusto Corrêa, state of Pará, as well as their distribution in rainy and dry periods. A total of 1,178 mites were collected and the most abundant families were Phytoseiidae, Tetranychidae, Tuckerellidae, Iolinidae and Cunaxidae, in addition to the unidentified taxa of the suborder Oribatida. The most abundant species were Oligonychus sp. (13.9%), Tuckerella ornata (12.2%), Amblyseius n. sp. 1 (12.1%) and Parapronematus sp. (10.5%). Among the predatory mites, the phytoseiid mites were more abundant and prevalent, with Amblyseius n. sp. 1 and Armascirus amazoniensis standing out. Amblyseius n. sp. 1 showed greater abundance in the rainy season than in the dry season, in both municipalities. Great diversity did note, mainly for predatory mites, while phytophagous mites were more abundant.
... The methods were based on the Braun-Blanquet (1964) method, but also on the % cover of species, and on Balázs (1960). In addition to the assessment of the natural state of the vegetation, diversity and grassland management analyses were also applied (Tóthmérész, 1995). The distribution of the life forms of the species forming the vegetation of the sites was also specifically addressed, based on Pignatti (2005). ...
Since 1992, data on the vegetation of the various grasslands in the country have been collected continuously and in recent years the vegetation of these areas has been surveyed repeatedly to monitor changes. Our aim has been to identify the conservation values and grassland management values of grasslands grazed by different animals, grasslands and wooded pastures that have been planted or restored. In the Pannonian region, we have also carried out studies in lowland mid-range, hilly areas. Areas grazed by horses, Hungarian grey cattle, sheep, goats and domestic water buffalo. The results of grazing with different animals at several study sites have been monitored and have been continuously monitored since 1994. In this paper, a brief overview of the results of the conversion of wooded pastures and deforested areas to pasture is presented. Results from three wooded pastures and one shrubland are summarised. Results from Hungarian grey cattle sheep and Hungarian domestic buffalo pasture are summarised. In all areas, grazing was successful in maintaining habitats. The maintenance of the scrub area and the preservation of its mosaicity were best ensured in the Hungarian grey cattle pasture. Sheep were responsible for maintaining the grassland vegetation. Water buffaloes ensured the maintenance of the pasture.
... From the point of view of the topic, diversity of vegetation is particularly important. Therefore, after contracting the data based on vegetation types, they were also analysed using Shannon, Simpson diversity, and using Rényi diversity profiles [64]. ...
In this study, we analyzed the phytosociological data from four sample sites located in the Pannonian region. The study areas, ranging from 2.4 to 2.5 hectares, have been subjected to goat grazing and mowing for 24 years. N1: Nagyréde, an overgrazed pasture with 24 goats; N2: Nagyréde, a mown field; C1: Csokvaomány, a lightly grazed pasture with 12 goats; and meadow C2: Csokvaomány, a site that is both mown and grazed. Six phytosociological surveys were conducted randomly in each area. We also considered the conservation value, biomass production, and forage values. Phytosociological data were processed using hierarchical cluster analysis and the non-parametric Kruskal–Wallis test. The overgrazed pasture (N1) exhibited the most degraded vegetation community, dominated by weeds and disturbance-tolerant species. The overgrazed (N1) pasture had a low forage value because of the different timing of treatments. Even in the lightly grazed pasture (C1), the proportion of species indicative of degradation was significant. The species composition of the areas indicated that the mown and subsequently grazed area (C2) had outstanding values. The species richness of C2 was twice that of the mown field (N2). Based on the present study, a combination of light grazing pressure and mowing is the most suitable approach for managing and economically utilizing these grasslands.
... The scale on the x-axis focuses on different aspects of diversity, allowing a more detailed analysis of the structure of the mite community based on simultaneous data on its richness, evenness and sensitivity to dominant species. Therefore, values on the x-axis further to the left of the graph are more sensitive to rare species, while values further to the right are more sensitive to abundant or common species (Tóthmérész 1995). This analysis was performed using the `renyi´ function (with the parameter hill = TRUE) of the vegan package (Oksanen et al. 2018) in the R environment. ...
... Possible seasonal variations (including sexdependent) were analyzed after dividing and referencing the data to the spring (April-June) and summer (July-September) groups, respectively, while the autumn (October-November) samples were excluded due to the small size (only four individuals). The taxonomic diversity of the food was analyzed via Rényi's index family (diversity profiles), which is considered one of the most useful methods for ordering samples according to their diversity (Tóthmérész 1995). The significance of differences in food diversity between the seasons and between the sexes was assessed by a permutation test based on Simpson's index (D), which gives higher weight to abundant taxa (Krebs 1999). ...
Although the Great crested newt (Triturus cristatus) is considered a generalist predator, there are few studies on its prey preferences across its wide range. Data on its feeding are virtually lacking for its southernmost populations; this study aims to fill this gap by analyzing the aquatic food spectrum and prey availability from three ponds in Stara Planina Mts., NW Bulgaria. Ponds were simultaneously sampled once per month; consumed prey items were collected using stomach flushing of captured newts, and hydrobiological samples were taken from each pond to establish potential prey diversity. Remains of ingested prey were found in 109 out of the 141 sampled adult newts (71 male and 70 female). Applying the widely used approach of "operational taxonomic units" (OTUs), prey items from stomach flushing were assigned to 27 OTUs (incl. plants and inorganic matter, and for females only-shed skin), while material from the hydrobiological samples-to 28 (20 of them were also found in the stomach content of the newts). The most frequent prey for both sexes were larvae from the family Chironomidae (found in 21% of the studied newts) and the most abundant superorder Cladocera (60% of the identified prey items). Male newts were more likely than females not to have eaten during the summer when the frequency of empty stomachs was higher compared to spring. For both sexes, prey diversity from stomach content was higher in the spring compared to the summer (Simpson's index values were respectively 0.76 vs. 0.12 for the males and 0.72 vs. 0.54 for the females), and females consumed more diverse prey during the summer, possibly as a result of their breeding behavior.
... Index (IVI) = relative frequency + relative dominance + relative density); Diversity Profile Analysis (Tóthmérész 1995); and spatial distribution of soil testing parameters. These Shannon index is a diversity index that accounts for the number of species individuals. ...
Mangroves serve as biotic fences of estuarine belts consisting of salt-tolerant plants that grow in intertidal zones and can be regenerated naturally as well as artificially. Mangrove regeneration refers to the process of restoring or rebuilding mangrove ecosystems that have been already degraded, damaged, or lost from their native place through the monitoring of geomorphological, taxonomical, pedological, and ecological aspects. The primary objective of this study was based on the remote sensing application through several important health monitoring indices over the minute part of Indian Sundarbans to prove the possibility of mangrove regeneration. Change detection analysis in the indices proves that there was possible growth and development in mangrove colonization over the same. The secondary objective is to comprehend the association of field-related study with the remotely sensed data on species diversity assessment over the same where the native species are Avicennia marina (Peyara Bain), Avicennia officinalis (Jat Bain), Avicennia alba (Kalo Bain), Aegialitis rotundifolia (Tora), Acanthus ilicifolius (Horgoj Kanta), Bruguiera gymnorrhiza (Kankra), Ceriops tagal (Goran), and Aegiceras corniculatum (Khalisi). The latter objective is associated with the tertiary one that unveils the correlation between several physico-chemical properties of soil samples taken from the field with the species accommodation. Textural classes are grouped between clay and silty clay that helps to get the foundation of hard wood-based species (Avicennia type) specifically with the salinity ranges between 200 ppt (Site 2) and 633 ppt (Site 1) approximately which presents that the zone is highly saline zone as specifically Avicennia species can sustain high salinity. Importance Value Index (IVI) and species diversity indices have been run to support whether the zone is diversified or not. Equilibrium between deforestation and regeneration through mangrove plantation has to be attained in the near future as deforestation for the livelihood purposes exists, so this newly born island locally named Dorabagda mangrove patch, upper part (Gopalganj) of Kaikhali village, would be the best experimental study site on mangrove regeneration.
... In ecology, Rényi's entropy has been used as an index of diversity to compare distinct ecosystems (Tóthmérész 1995;Ricotta 2000;Rennolls and Laumonier 2000;Tsiafouli et al. 2005;Lövei 2005; Magura, Lövei, and Tóthmérész 2010). This is done using diversity profiles, which plot Rényi's entropy against a selected range of q for multiple ecosystems. ...
Aim
An ecological community consists of species of various abundances that reflect their responses to the environmental conditions. A classic macroecological pattern, the species abundance distribution (SAD), has been studied for diverse taxa and communities and integrated into numerous modelling tools. Despite its widespread use, a mathematical model that can capture variations in the empirical SAD and describe its response to environmental changes is still lacking. By integrating the Maximum Entropy Theory of Ecology (METE) with a generalised entropy called Rényi's entropy, we aim to develop a new ecoinformatic model that can predict the variation of empirical SAD along multiple environmental gradients.
Location
Panama.
Taxon
Angiosperms.
Methods
We extend the METE using the Rényi's entropy as an uncertainty measure. We apply this extended METE, called Rényi model, to the tree abundance data from 49 plots in Panama and predict the SAD within each plot. We estimate Rényi's parameter q by fitting the predicted SAD to the empirical SAD in each plot. We further compile climate and soil data from the Panama plots and analyse their relationships with the estimated q using multiple regressions.
Results
Rényi model provides adequate description of the empirical SADs and outperforms lognormal or log‐series models in 40 of the 49 tree plots, according to the Akaike information criterion. Variations in Renyi's q estimates (from 1/2 to 1) reflect shifts in the empirical SADs. Multiple regressions reveal that P, Al and NH4, three soil chemicals that are important for tree growth and species distribution, significantly affect Renyi's q across plots.
Main Conclusions
These findings suggest that the Rényi model and Rényi's q can characterise the SAD of communities under environmental changes. They also indicate the potential of using generalised entropies to predict macroecological patterns in stressed ecosystems.
... Diversity indices representing different aspects of community structure and composition were calculated for each rodent community using Rényi's diversity profiles, Fisher's alpha [43], Rao's quadratic entropy [44], FDis [45], FRic, and FEve [46]. The Rényi diversity profile is a technique for ordering diversity [47] that produces curves indicating the richness and evenness of each community. Fisher's alpha is a scale-independent biodiversity indicator based on the curvature of the species abundance distribution. ...
Background
Phylogeny, combined with trait-based measures, offers insights into parasite sharing among hosts. However, the specific traits that mediate transmission and the aspects of host community diversity that most effectively explain parasite infection rates remain unclear, even for the Bartonella genus, a vector-borne bacteria that causes persistent blood infections in vertebrates.
Methods
This study investigated the association between rodent host traits and Bartonella infection, as well as how rodent community diversity affects the odds of infection in the Atlantic Forest, using generalized linear models. Additionally, we assessed how host traits and phylogenetic similarities influence Bartonella infection among mammal species in Brazil. To this end, rodents were sampled from ten municipalities in Rio de Janeiro, southeastern Brazil. Then, we calculated several diversity indices for each community, including Rényi’s diversity profiles, Fisher’s alpha, Rao’s quadratic entropy (RaoQ), Functional Diversity (FDis), Functional Richness (FRic), and Functional Evenness (FEve). Finally, we compiled a network encompassing all known interactions between mammal species and Bartonella lineages recorded in Brazil.
Results
We found no significant relationship between diversity indices and the odds of Bartonella infection in rodent communities. Furthermore, there was no statistical support for the influence of individual-level traits (e.g., body length, sex, and age) or species-level ecological traits (e.g., locomotor habitat, dietary guild, and activity period) on Bartonella infection in rodents. A country-scale analysis, considering all mammal species, revealed no effect of host traits or phylogeny on Bartonella infection.
Conclusions
This study highlighted wild mammals that share Bartonella lineages with livestock, synanthropic, and domestic animals, underscoring the complexity of their maintenance cycle within the One Health framework. A key question arising from our findings is whether molecular host–cell interactions outweigh host body mass and ecological traits in influencing Bartonella infection, potentially opening new avenues for understanding host–parasite relationships and infection ecology.
Graphical Abstract
... As diversidades foram comparadas entre os tratamentos (métodos de manejo) pelo teste t de Hutcheson (p ≤ 0,05) (Hutcheson, 1970). Além disso, foi construído um perfil de diversidade (Tóthmérész, 1995), utilizando-se a série exponencial de Rényi (Hα) (Rényi, 1961). A similaridade florística entre os sistemas de manejo dos bovinos foi avaliada por meio do coeficiente de Jaccard (Sj) (Ellenberg & Müller-Domboi, 1974) e a dissimilaridade por meio de Bray-Curtis (Brower;Zar & Von Ende, 1998). ...
Plantas daninhas geram substanciais prejuízos agropecuários. O estudo objetivou analisar o efeito de diferentes sistemas de manejo de bovinos na contaminação do esterco por plantas daninhas. Amostras de partes de fezes bovinas foram coletadas de animais confinados em curral (CC), em pastagem tradicional (PT) e em pastagem mista (PM). Essas amostras foram mescladas a areia autoclavada e colocadas em bandejas. A avaliação do banco de sementes foi aferida a cada 15 dias durante 3,5 meses. Para cada espécie foram determinados: a densidade, frequência e o valor de importância. Também foram calculadas a diversidade e a equabilidade, e efetuadas análises de comparação (teste t, similaridade, dissimilaridade e ANOSIM). No total, foram germinados 507 indivíduos distribuídos em 26 espécies, 17 gêneros e nove famílias. Considerando o CC, foram contabilizados 173 indivíduos e 12 táxons; para o PT, 180 indivíduos e 22 táxons; e para o PM foram 154 indivíduos e 14 táxons. Sete táxons foram semelhantes entre os três tratamentos, duas foram verificadas apenas no CC, sete apenas no PT e duas apenas no PM. A estruturação do banco de sementes variou de acordo com o sistema de manejo, no entanto as espécies com maior valor de importância foram iguais. A diversidade de plantas daninhas foi menor no esterco oriundo do gado confinado em curral. O esterco apresenta uma elevada riqueza de plantas daninhas, com variações na composição, estrutura e diversidade de espécies.
Palavras-Chave: Dispersão de sementes, plantas infestantes, endozoocoria, banco de sementes.
... These values measure the number of effective species and allow for accurate comparisons between samples (Chao and Jost, 2012). Rather than focusing on individual diversity indices (Green and Chapman, 2011;Daly et al., 2018), we examined in here the diversity profiles composed of Hill numbers ( q D) calculated using different degrees of sensitivity to species relative abundance, e.g., q ∈ [0; 3] (Chao and Jost, 2015;Tóthmérész, 1995). An illustrative case would be q = 0 at which the Hill number reduces to species richness, without any consideration of abundance. ...
... Segundo Magurran (2011) (Magurran, 2011;Romani, 2011). Estes índices podem apresentar resultados discrepantes para uma mesma comunidade devido ao peso dado às espécies raras: o primeiro prioriza a riqueza, enquanto o segundo confere maior importância à equabilidade (Hulbert, 1971;Peet, 1974;Tóthmérész, 1995). Melo (2008) sugere que índices de riqueza e equabilidade sejam analisados de forma separada aos de diversidade. ...
Estudos sobre florística e estrutura fitossociológica das formações florestais auxiliam a compreensão do funcionamento dos ecossistemas mediante manejo florestal. Objetivou-se, neste estudo, estimar alterações na composição, diversidade e estrutura florística de um fragmento florestal de 545,3 ha, em Anapu, Pará. Foram inventariados 9.604 indivíduos com diâmetro à altura do peito ≥50 cm, e efetivamente explorados 1.218 indivíduos com volume de 6.649,55 m³ de madeira, resultando em uma intensidade de exploração de 15,08 m³/ha. Um indicativo de que a exploração florestal foi eficiente quanto à composição florística é que se mantiveram remanescentes 87,32% do número de indivíduos das 107 espécies inventariadas antes da exploração. Dentre as famílias registradas, Fabaceae foi a que predominou antes e após a exploração. A espécie com maior número de indivíduos e índice de Valor de Cobertura foi o Acapu, enquanto no grupo das espécies exploradas foi a Timborana. A exploração alterou a ordem sequencial do Índice de Valor de Cobertura das espécies da comunidade florestal e resultou em alterações estatisticamente significativas no índice de diversidade e na estrutura da distribuição diamétrica. Por outro lado, mantiveram-se praticamente inalteradas a distribuição equitativa "J" Pilou (de 0,803 para 0,801) e a similaridade florística superior a 93,2% na comunidade arbórea após a exploração. Conclui-se que mesmo com as boas práticas realizadas pelos assentados do Projeto de Desenvolvimento Sustentável Virola-Jatobá, em conformidade ao atual sistema policíclico de manejo florestal brasileiro, o manejo comunitário não se demonstrou sustentável ecologicamente em vista ao desequilíbrio populacional provocado pela maior pressão de exploração de um reduzido número de espécies florestais.
... All cases were analyzed for two variants, both for abundance and biomass. The Rényi diversity index was used to determine biodiversity [33,34]. All the comparative analyses were performed using the Community Ecology Package 'vegan' version 2.6-4 with R version 4.3.1-"Beagle ...
A pilot ichthyological index was developed for use within the Water Framework Directive in the area of Central and Eastern Europe for dam reservoirs, which are heavily modified water bodies. This is the first approach to assessing this water body type based on ichthyofauna in Poland. Various fishing gear types were used. The tested dam reservoirs were scattered throughout the country, from lowland to mountainous areas, with very diverse hydrological and morphological characteristics and pressure ranges based on the TSI index. In preliminary work, a correlation matrix with the TSI index’s pressure indicator was tested based on the abundance or biomass of fish species, fish families present, fishing gear used, and fishing depth range for a total of 588 cases. As a result of the tests carried out, the preliminary indicator was based on the ratio of the number of the two families Cyprinidae and Percidae. The correlation between the developed indicator and the pressure index was strong (r = 0.77; p < 0.001). The Percidae family exhibited a strong correlation with the most connections in the matrix. Based on the obtained results, the principle of using already confirmed relationships, such as the ratio between Cyprinidae and Percidae fish families, in the assessment of eutrophication was confirmed to be effective, guaranteeing the effective initial assessment of ecological potential.
... Additionally, we traced diversity profiles, using the Rényi series, to compare the diversity among hydrographic regions. In the Rényi series, the minimum value of α results in an index that is equal to species richness (equability is not considered), and very high values of α assess only equability and disregard species richness [27]. In other words, we can only say that one river basin region is more diverse than another if the curves do not intersect. ...
The fish fauna of Rio de Janeiro has been extensively studied, resulting in a comprehensive database of species collected over more than three centuries. This study aimed to identify fish species, their locations, and compile scattered information to aid in climate action and freshwater conservation prioritization and an evaluation of the sampling effort to date, as well as to identify patterns of diversity and distribution of freshwater ichthyofauna, delineate biogeographic units, and explore similarity relationships between areas. Analyzing data from nearly 25 ichthyological collections and literature on original species descriptions revealed 346 fish species: 172 freshwaters native, 22 allochthonous, and 152 marine species. The checklist includes updated species names. The sampling effort in Rio de Janeiro is high, especially in coastal lowlands. The findings indicate that inventory work is still needed in certain areas. Five bioregions of freshwater ichthyofauna were identified, along with six major areas of higher species richness. This biogeographic assessment underscores the diverse and distinctive freshwater fish fauna in the basins of Rio de Janeiro, with well-defined biogeographic units.
... The correlation between the abundance and the frequency of occurrence of OTUs in the fecal samples was derived using Spearman's rank correlation coefficient (Rho). Comparison between sexes was done in two ways: 1) ordering according to taxonomic diversity of diet via Rényi's index family (diversity profiles) (see Tóthmérész 1995); 2) testing for a difference based on the frequency of occurrence of the separate categories of evasiveness and hardness (using Chi-square test). Statistical procedures were performed using PAST 4.07 (Hammer et al. 2001). ...
The Balkan wall lizard (Podarcis tauricus) is a small-sized ground-dwelling species distributed in southeastern Europe and northwestern Anatolia. Although some insights into its diet and food preferences were published, there is still a lack of knowledge of its feeding ecology in parts of its range, especially in Bulgaria. Our results showed that the trophic spectrum of P. tauricus in NW Bulgaria consists of insects and arachnids. At a lower taxonomic level, two orders-Hymenoptera (incl. Formicidae) (24.63%) and Heteroptera (23.19%) have almost equal participation and together represent nearly 50% of the diet, while among other groups, only Orthoptera (13.04%) and Araneae (11.59%) have a significant presence.
... 4.03) to calculate species richness (Chao1), Shannon-Wiener index (H′), Simpson's dominance index (D), Evenness (E), and alpha-species richness (Hammer et al., 2001). The Rényi diversity profile (Tothmeresz, 1995), was used to depict the diversity curves of the five stands (Fig. S1). It depends upon a parameter alpha, such that for alpha = 0, this function gives the total species number and alpha = 1 gives an index proportional to the Shannon index. ...
... Thus, Hill's diversity profile is especially useful for verifying how the relative presence of more abundant species/taxa in comparison to less abundant ones contributes to altering the diversity of the organism community. Therefore, the scale on the x-axis focuses on different aspects of diversity and thus allows a more detailed analysis of the structure of the mite community based on simultaneous data on its richness, its evenness and its sensitivity to dominant species, with the values on the left side of the graph more sensitive to rare species and the values on the right side are more sensitive to abundant or more common species (Tóthmérész 1995). This analysis was carried out using the 'renyi' function (hill = TRUE) from the vegan package (Oksanen et al. 2018) in R. ...
The objective was to quantify and analyze the diversity of mites associated with native and cultivated açaí palms crops, as well as their distribution in the dry and rainy seasons in the municipalities of Bragança and Augusto Corrêa, state of Pará. Rarefaction curves were generated for diversity values using the statistical programming language R, rarefaction curves for estimates of richness and equitability, and analysis of variance with permutations. A total of 2069 mites from 28 families were sampled, being most representative Phytoseiidae (32.4%), Phytoptidae (13%), Cunaxidae (7.7%), Tetranychidae (5.6%) and Tydeidae (4.9%). Among predators, the most abundant species were Amblyseius sp. 1, Armascirusamazoniensis Wurlitzer & Silva, Iphiseiodeszuluagai Denmark & Muma, Scutopalustomentosus Rocha, Skvarla & Ferla, and the phytophagous mites Acaphyllisa sp., Davisella sp., Oligonychus sp. and Retracusjohnstoni Keifer. In the rainy season, more mites were sampled (n = 1176) than in the dry season (n = 893). The greatest richness was observed in the dry period (73 species) and diversity was also greater in this period. In the municipality of Bragança there was greater richness (78 species) and the cultivated açaí trees had greater acarine abundance (74.7%) than the native ones. However, natives had slightly higher wealth (6%) than those cultivated. The diversity and richness of predatory mites show the potential of the Amazon biome to be used in applied biological control.
... The taxonomic diversity of the prey remains in the faecal pellets was analysed via Rényi's index family (diversity profiles), which has been considered one of the most useful methods for ordering samples according to their diversity (Tóthmérész, 1995). Food selection was analyzed by comparing the relative abundance of the OTUs from the faecal samples with those from the pitfall traps, using the electivity index of Vanderploeg and Scavia (1979) (E*), which represents a modification of the Ivlev's forage ratio, but has better theoretical justification (Lechowicz, 1982). ...
The Common wall lizard (Podarcis muralis) has the largest range among the genus Podarcis. Although there are a number of studies on its diet, data on regional level remains insufficient, particularly from a purely ecological perspective. We investigated 194 individual faecal samples of P. muralis obtained from two localities in western Bulgaria with the aim of clarifying the composition of the trophic spectrum of the species, as well as the intra-population characteristics in terms of age and sex. In one study site, we compared the realized trophic niche (prey items from the faecal pellets) with the fundamental (invertebrates collected via pit-fall traps exposure). We confirmed that P. muralis is an opportunist in terms of feeding and has a very wide trophic spectrum including several taxa, which have not been reported until now as a part of the species’ diet. We revealed differences in feeding behavior between subadults and adults, as well as between males and females. Adults have higher diversity in the food spectrum compared to subadults. According to sexes, females have more varied diet. We also report for the first time for the species six cases of keratophagy. Also, we identified a relatively frequent occurrence of saurophagy (n = 16), including in females and subadults, for which this phenomenon has not been recorded so far.
... Thus, Hill's diversity pro le is especially useful for verifying how the relative presence of more abundant species/taxa in comparison to less abundant ones contribute to altering the diversity of the organism community. Therefore, the scale on the x-axis focuses on different aspects of diversity and thus allows a more detailed analysis of the structure of the mite community based on simultaneous data on its richness, its evenness and its sensitivity to dominant species, with the values on the side left side of the graph more sensitive to rare species and the values on the right side are more sensitive to abundant or more common species (Tóthmérész, 1995). This analysis was carried out using the `renyi´ function (hill = TRUE) from the vegan package (Oksanen et al. 2018) in R. ...
The objective was to quantify and analyse the diversity of mites associated with native and cultivated açaí palms crops, as well as their distribution in the dry and rainy seasons in the municipalities of Bragança and Augusto Corrêa, state of Pará. Rarefaction curves were generated for diversity values using the statistical programming language R, rarefaction curves for estimates of richness and equitability and analysis of variance with permutations. A total of 2,069 mites from 28 families were sampled, being most representative Phytoseiidae (32.4%), Phytoptidae (13%), Cunaxidae (7.7%), Tetranychidae (5.6%) and Tydeidae (4.9%). Among predators, the most abundant species were Amblyseius sp. 1, Armascirus amazoniensis Wurlitzer & Silva, Iphiseiodes zuluagai Denmark & Muma, Scutopalus tomentosus Rocha, Skvarla & Ferla, and the phytophagous mites Acaphyllisa sp., Davisella sp., Oligonychus sp. and Retracus johnstoni Keifer. In the rainy season, more mites were sampled (n = 1,176) than in the dry season (n = 893). The greatest richness was observed in the dry period (73 species) and diversity was also greater in this period. In the municipality of Bragança there was greater richness (78 species) and the cultivated açaí trees had greater acarine abundance (74.7%) than the native ones. However, natives had slightly higher wealth (6%) than those cultivated. The diversity and richness of predatory mites show the potential of the Amazon biome to be used in applied biological control.
... Diversity profiles (or Renyi curves) relate several diversity indices via a scaling parameter (α). Thus, for α = 0 they depict the number of species (S); for α = 1 and 2, their values corresponds to the Shannon and Simpson indices, respectively; and for α = 4 they correspond to the inverse of the Berger-Perker dominance index (Tothmeresz 1995;Southwood and Henderson 2000). PAST was also used for individual rarefaction analysis for evaluation of difference in species numbers. ...
Arthropod faunas have become impoverished in recent years in abundance as well as in diversity, but so far little evidence exists concerning spiders. In 2022, we repeated pitfall trap collections of spider assemblages completed 25 years previously in coastal dune habitats of the Hanstholm Reserve of National Park Thy, Denmark. Traps were placed approximately at the same spots, i.e. the habitats (white dune, grey dune, dry dune heathland, wet dune heathland, low pine plantation) were represented approximately as before. Contrary to most previous reports of insect decline, we found only weak evidence of reduction in abundance, but strong indications of reductions in faunistic value based on changes in ecological traits. Within the same period of spring and with the same number of traps, we collected 12% fewer spider individuals and 13% fewer species; rarefaction indicated that the lowered species richness was real. Species diversity had decreased and dominance increased. Changes in indices of ecological traits showed that the fauna had changed into decreased contribution of habitat specialists and species of restricted Danish distribution; the proportion of aeronauts had increased; the average body size had decreased. Indices of assemblage microclimatic niche positions and niche widths showed increased representation of shade and humidity loving species. Most of these changes were repeated in each of the habitats. Finally, we found evidence of a phenological shift towards activity earlier in spring in some species.
Implications for insect conservation
We discuss possible management measures to counteract the observed trend towards reduced faunistic value.
... These analyses were carried out using Bray-Curtis distance and 9999 bootstrapping replicates with PAST version 3.24, a software for analysis in paleoecology (Hammer et al., 2001). PAST was also used to compare diversity between treatments using the diversity profile according to the formula of (Tóthmérész, 1995), and the fungal diversity of each plantation was compared to the arable soil in terms of Shannon's index using the t-test (Hutcheson, 1970). ...
As soil fungi are major players in the carbon accumulation process, the two main fungal degraders in topsoil, Ascomycetes and Basidiomycetes, were investigated as indicators of land use effectiveness in increasing soil carbon accumulation and soil function. The study focused on the soil organic carbon content increase in a 20-year short rotation forest cycle with broadleaf woody plantations compared to a nearby arable cropping system. Total fungi, Ascomycota and Basidiomycota, were quantified in terms of DNA copy number, with specific probes using SYBR® Green I dye on the QuantStudio™ 3D digital PCR system (dPCR). Previously,
next generation sequencing analysis using a general primer confirmed that Ascomycota and Basidiomycota were the most represented phyla and that fungal community composition significantly differed between treatments. A range of key soil enzyme activities for the C-cycle were also assessed. Total organic carbon content (TOC), microbial biomass in term of dsDNA and enzyme activities significantly increased in woody plantations compared to arable soil. The TOC increase differed significantly also between wood species, Salix and Robina gave the greatest increase (+30 and 20% respectively), followed by Populus (+12), microbial biomass highly correlated with TOC showing the same trend. Total fungi, Ascomycota and Basidiomycota increased significantly in three woody plantations compared to the arable soil system. Ascomycota in the woody plantations increased two to four times (average 3144 n copies µl-1 of DNA) compared to the arable soil (1419 n copies µl-1); Basidiomycota were almost absent in arable soil (av. 94 n copies µl-1) and increased five to six times in woody plantations (av. 490 n copies µl-1). Total fungi and ascomycetes correlated strongly with microbial biomass and TOC, whereas basidiomycetes did not. These findings showed that Ascomycota represent the largest portion of fungi in agricultural soils even after a 20-years short rotation forest cycle and they can be taken as indicators of carbon accumulation processes. Therefore, this study suggests that joining the Ascomycetes quantity in the topsoil to the Ascomycota:Basidiomycota ratio seems a good option when setting regional strategies for improving C accrual in farmland with the short-term afforestation.
... The diversity of the seven orchards was compared using the Rényi exponential series (exp(Hα) = exp [(1/1-α) ln∑piα]). This series includes the main diversity indices, from the most sensitive for rare species (low α value) to those that give greater weight to abundant species (high α values) (Tóthmérész 1995). In this series, α = 0 corresponds to the total number of species, α = 1 to the Shannon index, α = 2 to the Simpson index and α → ∞ to the Berger-Parker index. ...
In this study we performed the sampling of phytoseiid mites in different apple production orchards, and we evaluated the richness and abundance of these mites, as well as their distribution in the different strata of the plants. Furthermore, we studied how the different apple tree cultivars affect the diversity and distribution of these predatory mites. Collections were carried out in apple orchards in three different production areas: 1-organic agriculture (Antônio Prado, RS); 2-conventional agriculture (Muitos Capões, RS); 3-regenerative agriculture (São Joaquim, SC). In total, seven orchards were evaluated, in Muitos Capões and São Joaquim, two orchards of the Fuji and Gala, whereas in Antônio Prado, three cultivars (Eva, Fuji and Gala) were considered. In each orchard, 40 plants were evaluated, and from each plant a median branch was randomly chosen from which a leaf was removed from the apical, median and basal thirds. The collected leaves were taken to the laboratory, they were observed and the mites found mounted in Hoyer's medium and identified. A total of 695 phytoseiid specimens were collected. Greater abundance was noted in the apical stratum of plants of the Gala cultivar, demonstrating the effect of cultivar and stratum on phytoseiid richness, abundance and distribution. Neoseiulus californicus (McGregor) (Phytoseiidae) was the main species in areas of conventional and regenerative cultivation, being present in all evaluated orchards, but with low occurrence in areas of organic management. In organic orchards, species of the genus Euseius [Euseius mesembrinus (Dean) and Euseius inouei (Ehara & Moraes)] (Phytoseiidae) were more abundant. The results suggest that producers consider less intensive use of pesticides and herbicides in orchards in order to maintain populations of predatory mites due to their potential for biological control.
... The influence of both richness and evenness on the Rényi diversity profile is considered in the diversity measurement. The differences in diversity curves for each of the five forest types were displayed using the Rényi diversity profile (Tóthmérész, 1995;Dejene et al., 2017). The diversity profile was plotted using PAST software version 3.14 . ...
Carbon stock and diversity of species together address the two most pressing concerns for successful ecosystem functioning and management, namely climate change and biodiversity loss. Understory vegetation is a significant indicator of plant biodiversity, contributing to forest carbon storage, sustaining species, and providing many ecological services. However, little research has been done about the contribution of the understory carbon stock in the forests, most likely because these understory components only make up a small portion of the total carbon stock of the forest ecosystem. To fill this knowledge gap, the current study sought to study the baseline understory (shrub and herb) diversity and carbon stock from the Zabarwan Mountain Range. Data on the characteristics of the understory vegetation in five different forest types were gathered using a random sample method. Using the Pearson method, we calculated the correlation coefficient between the diversity parameters and the carbon stock. The calculated average total carbon stock in the understory was determined to be 3.93 Mg C/ha (1.55–9.2 Mg C/ha). The shrub layer contributed a maximum value of 82 % of carbon stock. The increasing trends in total understory carbon were Parrotiopsis forest < Broad-leaved forest < Oak forest < Acacia forest < and Pinus forest. Species-wise, the shrub Parrotiopsis jacquemontiana was found to contribute a maximum average carbon stock of 3.11 Mg C/ha (47.76 %) and can be regarded as a key indicator understory species for the restoration of Himalayan forests. The decreasing order of trends in Shannon–Wiener diversity index value in the study area was Oak forest > Broad-leaved forest > Acacia forest > Pinus forest > Parrotiopsis forest. Overall, the data show that coniferous-dominated woodlands had higher understory carbon stocks than other kinds of woodlands. The data acquired highlights the importance of shrub carbon stock storage in the understory layer in this Himalayan region. The current research on understory vegetation provides strong evidence for maintaining forest management practices that enable and encourage the planting of multiple layers of vegetation in landscape restoration as approaches to improve biodiversity while increasing resistance to climate change.
... To compare species diversity among seasonal assemblages, we performed the 4 approach for diversity profiles, which the main purpose is to compare diversities in several samples using graphs (Tothmeresz, 1995). The bootstrapping option (giving a 95% confidence interval) is based on 2000 replicates, using PAST software (Hammer et al., 2001). ...
Dehesas (i.e., substeppic prairies with Quercus suber) represent a poorly studied Mediterranean habitat type of high eco-biogeographic interest. Here, we applied a point-transect method along a yearly cycle (from spring to autumn), to focus on seasonal differences in bird assemblages inhabiting a Dehesas landscape in north-western Sardinia (Italy). We confirmed the presence of Mediterranean species with
restricted ranges (e.g. Sturnus unicolor, Sylvia sarda). At the community level, seasonal patterns show significant differences among mean abundance, with a maximum in autumn and a minimum in summer. The highest values in autumn may be explained by the aggregations of wintering small passerines. Considering the univariate metrics of diversity, the number of species significantly differs
among seasons, with the richest community in spring. Shannon-Wiener diversity and Margalef (normalized richness) were higher in spring, and summer compared to autumn. Habitat heterogeneity of these landscape mosaics, driven by historical agro-pastoral practices (fires and pastures), together with the presence of patchy 'key structures', positively affects bird species richness and abundance, improving, respectively, the number of niches and resources. More resource effort should be devoted to study these habitat types recently interested in an increased anthropogenic pressure (urban sprawl and road infrastructures, location of wind power plants, etc.).
... The following metrics were used to analyze hawkmoth diversity: composition, abundance (N), richness (S), Shannon diversity, uniformity indexes (H' and J'), and Berger-Parker dominance (BP) (Magurran 2011). A diversity of profiles were used to assess species diversity between strata, based on the Rényi series (Tothmeresz 1995) considering the following index rates: total richness (α = 0), Shannon-Weiner index (α = 1) and Simpson dominance (α = 2). Analysis of variance (ANO-VA) was performed to test (t-test: LSD) whether there was a significant difference in abundance between strata (canopy, midstory and understory), for samples (30) The species richness estimates were calculated using the program "ESTIMATES" (Statistical Estimation of Species Richness and Shared Species from Samples) (Colwell 2013), applying the non-parametric methods Chao 2 and Jackknife 1. ...
The present study analyzed the vertical stratification of hawkmoths in an area of the Dense Ombrophylous Forest in the Amazon. The moths were captured through light traps with ultraviolet lamps F15 T12 LN installed in three strata (canopy, midstory, and understory) from 6 pm to 7 am, during the first quarter to new moon period, on three consecutive nights per month during May 2019 to February 2020, in the Tapajós National Forest located in the state of Pará, Brazil (02°51’23.3”S, 54°57’31.0”W). This study analyzed 33 species (S) and 775 specimens (N) of Sphingidae. The sphingofauna had a high concentration, mainly in the upper strata, with greater emphasis on richness (S = 28), abundance (N = 687), and Berger Parker dominance (BP = 0.72) found in the forest canopy. The canopy’s dominance stood out because the species Erinnyis ello (Linnaeus, 1758) was more abundant in this stratum (N = 492). PERMANOVA analysis indicated significant differences in all strata. Therefore, our study provided important information about the vertical distribution of moths, showing that their richness, abundance, and species composition are distinct between strata.
KEY WORDS:
Canopy; Erinnyis ello; hawkmoths; sphingofauna; strata
... Finally, to compare species diversity before-after the impact due to the musical festival, in I and C assemblages (and between urban settlements, U, and agro-mosaic, M, habitat types), we performed the approach for diversity profiles (bootstrapping option; 95% confidence interval; 2000 replicates), which the main purpose is to compare biological diversity in several samples using graphs (Tothmeresz, 1995). ...
An assessment of the short-term effects of an outdoor music festival (Jova Beach Party event; July 2019; central Italy) on bird assemblages has been carried out, adopting a BACI (Before-After-Control-Impact) survey design, and using the point counts method both in the impact site (Impact, I; where the concert was held) and in comparable Control site (C). In the I site, data have been stratified both for urban (U) and agro-mosaic (M) habitats. When comparing before and after the music event, in IU site, the species richness and the Hill diversity index decreased, differently from CU where species richness a species abundance increased. Diversity profiles highlighted the impoverishment of bird assemblages after the event, but only in the Impact urban habitats. After the musical event, individual rarefaction curves for richness were lower in IU after the concert, while, differently in CU curves are higher. These data suggest an impact in bird assemblages limited to the urban site, due to the stress mainly induced by high intensity noise pollution. Musical events may disrupt the structure of synanthropic bird assemblages, inducing a dispersal of individuals towards the surrounding landscape. Starling (Sturnus vulgaris) appeared a particularly sensitive bird. However, further efforts are necessary to study the effects of these events at species level.
... Để mô tả SAD của các loài cây trong 2 môi trường sống với các chế độ xáo trộn khác nhau, nghiên cứu này đã sử dụng đường cong hàm phân phối tích lũy (Empirical Cumulative Distribution Function -ECDF) và độ phong phú theo thứ hạng (Rank Abundance Diagrams -RAD) [14]. Bên cạnh đó, đường cong Robbins và hồ sơ đa dạng cũng được đưa vào trong nghiên cứu nhằm phân tích những khác biệt về độ hiếm hoặc ưu thế của các loài, đánh giá ảnh hưởng của sự xáo trộn đối với SAD và so sánh tính đa dạng loài trong 2 môi trường sống [23,24]. ...
Mô hình phân bố độ phong phú của các loài (SAD) là một mô tả định lượng về số cá thể của các loài trong một khu vực hoặc ô lấy mẫu, cung cấp nền tảng giúp hiểu các đặc điểm của quần xã và cơ chế duy trì sự đa dạng. Nghiên cứu này phân tích sự khác biệt về SAD của các loài cây gỗ và cơ chế đằng sau của chúng ở hai môi trường có chế độ xáo trộn khác nhau trong rừng lá rộng thường xanh ở Vườn quốc gia Phia Oắc-Phia Đén, tỉnh Cao Bằng. Dữ liệu được thu thập trên 06 ô nghiên cứu 01 ha, trong đó, 03 ô nghiên cứu nằm trong vùng lõi và 03 ô nằm trong vùng đệm, đại diện cho môi trường không bị xáo trộn và bị xáo trộn tương ứng. Nghiên cứu đã sử dụng các đường cong tích lũy và Robbins, hồ sơ đa dạng và 06 mô hình SAD để mô tả dữ liệu quan sát. Kết quả cho thấy: (1) Thành phần loài trong hai môi trường sống có sự khác biệt về số lượng và độ phong phú loài. (2) Tính đa dạng và mức độ đồng đều trong môi trường không bị xáo trộn cao hơn so với môi trường bị xáo trộn. (3) Lý thuyết trung lập và ổ sinh thái cùng đóng vai trò quan trọng trong việc giải thích cơ chế duy trì tính đa dạng loài trong các quần xã ở khu vực nghiên cứu. (4) Mô hình trung lập chỉ ra rằng, có sự di cư loài từ các lâm phần trong vùng lõi sang vùng đệm của Vườn quốc gia.
Scattered trees are hubs of biodiversity. Here, we present a study in which fungal communities in the caulosphere of scattered individual trees were compared to those of woodlands. We compared alpha and beta diversities of wood- and bark-inhabiting fungi from the stems of trees across seven vegetation types belonging to three species: Pinus muricata, Quercus agrifolia and Notholithocarpus densiflorus. Scattered pines were among the investigated vegetation types. Correlations between stand density, or other tree features, and alpha diversity matrices, were studied with six Generalized Linear Models (GLMs), while the effect of spatial dispersion of trees was studied by correlating Ripley's K values with diversity. Results show that scattered trees represent a hub for biodiversity of wood and bark fungi. We found that caulosphere fungal richness in scattered pines was higher than that of pines growing in stands and was as high as that in notoriously biodiverse oak woodlands. Beta diversity analyses showed that the high fungal diversity in scattered pines is explained by the large number of taxa unique to pines, by a significant overlap of fungi between scattered pines and other vegetation types, and by a significant number of fungi unique to scattered pines. The GLMs showed significant correlations between high species richness, Shannon's and Simpson's indices and low forest density. Finally, we show that the fungi in or on the stems of more dispersed vegetation types are more diverse. These surprising results suggest that preserving or planting scattered trees is a cost-effective strategy that could support as much, or even more, caulosphere fungal biodiversity than entire woodlands.
Vizsgálatainkat a Zámolyi-medencében található Zámoly településtől északkeletre elhelyezkedő Páskom (Reznek-dűlő, Túzok-rét) területén végeztük el. A terület a Pro Vértes Természetvédelmi Közalapítvány tulajdona, melynek jelentősége, hogy a Zámolyi Tsz a 80-as években feltört, és a 2000-es évek elejéig gazdálkodás alatt tartott. Tekintettel arra, hogy a 80-as évek elejéig ott élt a Zámolyi-medence túzokállománya, a területet visszagyepesítették. A jelen munka célja, hogy a következő kutatási kérdésekre feltárjuk a válaszokat: hogyan alakul a fajszám a különböző gyeptelepítések során? Milyen arányban változtatja meg a természetvédelmi kezelés, a telepítés utáni kaszálás és a magyar szürke szarvasmarhákkal történő legeltetés a gyep gazdasági és természetvédelmi értékeit? Melyek gyepghagdálkodási és természetvbédelmi szempontból is hasznos gyeptelepítési technikák? A terület növényzeti változását 2012-ben és 2020-2022-ben végzett cönológiai vizsgálatokkal követtük. Minden mintaterületen 7-7 cönológiai felvételt készítettünk, ahol a mintaterületekben előforduló fajokat, valamint azok %-os borítási értékeit adtuk meg. A gyepgazdálkodási szempontból fontos pázsitfű fajok az eltelt időszak alatt nagy szerepet kaptak, 10% fölötti átlagos borítási értékkel fordultak elő. A Raunkiaer-féle életforma elemzés alapján a vizsgálati területeken jelentős különbségek nem voltak, a legtöbb faj az évelő növények közé tartozott. A Pignatti-féle életformák megoszlásában már mutatkoztak különbségek, de egyértelműen látszik, hogy a területen legeltetést még nem folytattak, hiszen nem szaporodtak fel a kúszó vagy tarackoló életmódú évelő- és a tőlevélrózsás fajok. A mintaterületeken legmagasabb arányban a természetes zavarástűrők fordultak elő, kivéve a parlag mintaterületen, ahol legmagasabb borításban már a természetes kompetítorok voltak (Festuca rupicola). A direkt vetésű területen még 2022-ben is a legmagasabb arányban a ruderális kompetítorok mennyisége volt. A területet a gyeptelepítés után 3 éven át kaszálták is, ami jelentősen hozzájárulhatott minden mintavételi területen, táblában a fajgazdagsághoz. Számos tanulmány is megerősíti, hogy a kaszálás növeli a felhagyott területek fajgazdagságát. Végezetül a vizsgált telepítési módok közül a szénamurvás vetést javasoljuk, ami nemcsak természetbarát, de hosszú távon is gazdasági haszon elérésére alkalmas.
In the area of ecological research, the study of species diversity of a community or population seems to have been fully developed. However, the problem of how the distributions and expectations of the sample diversity indices are affected by population diversity has received little attention. This paper is concerned with methods of moments of improved generalized diversity index, N(α,β) due to Shamia's (2013) proposal which includes special cases. This improved index is a further generalization due to Good as described by Backowski et al., (1997). In this article, the first four central moments of N(α,β) are derived for both general species relative abundance models: the Broken-Stick model and Sequential-Breakage model within a range of (α,β) considered. This allows the determination of the skewness and kurtosis of N(α,β) and thus gives information about the behaviour of the distribution of the improved index. The results are applied for comparing the diversities of the communities based on the samples n>s, and they yielded certain desirable monotonicity properties for large samples. It can be also shown that such indices are asymptotically normally distributed.
The plant growth phases are regulated by environmental factors, including soil microorganisms and physico-chemical cues. The role of endosymbionts and rhizobia in legumes is well documented, but the role of nonsymbiotic rhizospheric bacterial groups on plant growth phases is not well understood. To understand the role of soil bacteria and physico-chemical factors on the phenophases of a legume plant, cowpea (Vigna unguiculata L. Walp) was selected, as it is one of the valuable food legumes grown in the tropics for grains, vegetables (pods and leaves), fodder, and dry haulms.
Field experiments were carried out during the March–June period for 2 consecutive years at chemically and organically treated field plots. The physico-chemical factors associated with cowpea growth were measured directly from the field plots. Growth-related indicators like plant height, leaf area index, number of flowers per plant, and number of pods per plant were observed and calculated at the vegetative, reproductive, and mature phases of cowpea. Hierarchical cluster analysis was done to understand the association of different soil bacterial groups present in the soil. Diversity profiles of bacteria were done at the control, chemical, and organically treated plots. To understand the relative importance of physico-chemical factors and soil bacterial groups on plant growth, an artificial neural network (ANN) model was constructed. The model was run for the vegetative, reproductive, and mature phases of plant growth using several sets of data.
Sensitivity analysis revealed that soil bacterial groups like symbiotic nitrogen-fixing bacteria, starch hydrolyzing bacteria, and phosphate-solubilizing bacteria were relatively important during the vegetative, reproductive, and mature growth phases of cowpea, respectively. Among the physico-chemical factors, root temperature and air temperature were the most sensitive factors associated with the phenophases of cowpeas.
Mangroves are the biotic fence of estuarine belts consisting of salt-tolerant trees and shrubs that grow in intertidal zones can be regenerated naturally as well as artificially. Mangrove regeneration refers to the process of restoring or rebuilding mangrove ecosystems that have been already degraded, damaged, or lost from their native place through the monitoring of geomorphological, taxonomical, pedological, ecological aspects. Primary objective of this study lays on the remote sensing application through several important health monitoring indices ( NDVI, SAVI, OSAVI & VCCI ) over the minute part of Indian Sundarbans to get proved on the possibility of mangrove regeneration. Change detection analysis on indices proves that there is possible growth and development in mangrove colonization over the same. Secondary objective is to comprehend the association of field related study with the remotely sensed data on species diversity assessment over the same where, the native species are Peyara Bain, Jat Bain, Kalo Bain, Tora, Horgoj Kanta, Kankra, Goran, Khalisi . Latter objective is associated with the tertiary one that unveils the correlation between several physico-chemical properties of soil samples taken from the field with the species accommodation. Textural classes are ranged between clay to silty clay that helps to get foundation of hard wood based species (Bain type) specifically with the salinity ranges between 200ppt (Site 2) to 633ppt (Site 1) approximately that presents the zone is highly saline zone as specifically Bain types can sustain high salinity. Importance Value Index (IVI) & species diversity indices have been run to support whether the zone is diversified or not. Equilibrium between deforestation and regeneration through reforestation has to be attained in near future as deforestation for the livelihood purposes exist so that this newly born island named Dorabagda forest, upper part (Gopalganj) of Kaikhali village would be the best example of mangrove regeneration site.
Three commonly used measures of diversity, Simpson's index, Shannon's entropy, and the total number of species, are related to Renyi's definition of a generalized entropy. A unified concept of diversity is presented, according to which there is a continuum of possible diversity measures. In a sense which becomes apparent, these measures provide estimates of the effective number of species present, and differ only in their tendency to include or to ignore the relatively rarer species. The notion of the diversity of a community as opposed to that of a sample is examined, and is related to the asymptotic form of the species-abundance curve. A new and plausible definition of evenness is derived.
Many explanations for diversity patterns have been proposed, and there have been several recent reviews of the subject (Pianka 1966, 1974; Ricklefs 1973; Pielou 1975). High diversity has been attributed both to intense competition which forces niche restriction (Dobzhansky 1950; MacArthur and Wilson 1967)and reduced competition resulting from predation (Paine 1966; Harper 1969; Janzen 1970; Connell 1975). Diversity has been positively correlated with productivity (Connell and Orias 1964; Pianka 1966; MacArthur 1969) and negatively correlated with productivity (Yount 1956; Margalef 1969). The question is far from settled. This paper develops an approach to the problem of species diversity based on the nonequilibrium interactions of competing populations. Under nonequilibrium conditions, differences in diversity are strongly influenced by variations in the rates of competitive displacement between communities, and such factors as relative competitive abilities, niche partitioning, etc., may not be particularly important. This approach deals primarily with the maintenance of diversity, as opposed to the generation of diversity. While most of the current diversity hypotheses have some
This paper puts forth the view that diversity is an average property of a community and identifies that property as species rarity. An intrinsic diversity ordering of communities is defined and is shown to be equivalent to stochastic ordering. Also, the sensitivity of an index to rare species is developed, culminating in a crossing-point theorem and a response theory to perturbations. Diversity decompositions, analogous to the analysis of variance, are discussed for two-way classifications and mixtures. The paper concludes with a brief survey of genetic diversity, linguistic diversity, industrial concentration, and income inequality.
A criterion for comparing diversity is offered based on dominance patterns involving all the proportional species abundances. The method is applied by plotting percentage cumulative abundance curves. This can reveal that some assemblages cannot be compared in terms of diversity or equitability and that intrinsic diversity indices cannot under these circumstances be relied upon. The behaviour and interpretation of these dominance curves under different circumstances is explored using examples from macrobenthic and marine nematode studies. Dominance curves are also compared with Sanders' rarefaction curves and the relative advantages discussed. It is recommended that these graphical methods be routinely applied to marine biological data before calculating more complex diversity or equitability indices.
A family of species diversity measures proposed by Hurlbert (1971) is defined as the expected number of species in a random sample of m individuals from a population. For m = 2 this measure is equivalent to Simpson's diversity index. For larger m, the measure is increasingly sensitive to rare species. In this paper we use unbiased estimation theory to obtain a minimum variance unbiased estimator for this family of diversity measures. An unbiased estimator of the sampling variance is also obtained. These results are then used to partition the variation in sample diversity between random sampling error and local variation community diversity.
If the concepts of biological indices and biomonitoring at the multi-species level are to prove viable, then meiofauna and marine nematodes in particular should be an ideal group with which to test the hypothesis. Many attempts to assess the structure of species assemblages, such as the use of diversity indices, nematode: copepod ratios and the graphical method of log normal plots, have been shown to be theoretically unsound and/or impractical, especially for routine use by extension workers. A method of assessing shifts in dominance patterns which involves all the proportional species abundances is suggested as a better means of comparing diversity. A modified method of rapidly assessing Simpson's dominance-weighted diversity index is also advocated as being of practical use. In combination, they should enable the diversity aspect of the multi-species approach to biomonitoring to be rigorously and exhaustively evaluated.
Diversity Indices, Biotic Indices and Similarity Indices are reviewed considering their ecological application, both theoretical and practical. Eighteen diversity indices in eight groups, nineteen biotic indices in ten groups and five similarity indices are examined for their applicability to biological systems, particularly aquatic ecosystems. All the diversity indices were found unsuitable except for Simpsons D, Hurlberts PIE, indices based on the theory of Runs (SCI and TU) and possibly McIntosh's M. Indices based on information theory, such as H′ and H, although the most commonly used diversity indices were unsatisfactory due to the lack of exploration of their biological relevance. The use of H′ in aquatic ecosystems is only justified until the more satisfactory indices are adequately field tested.
The concept of information functions of type β (β > 0) is introduced and discussed. By means of these information functions the entropies of type β are defined. These entropies have a number of interesting algebraic and analytic properties similar to Shannon's entropy. The capacity of type β (β > 1) of a discrete constant channel is defined by means of the entropy of type β. Examples are given for the computation of the capacity of type β, from which the Shannon's capacity can be derived as the limiting case β = 1.
The recent literature on species diversity contains many semantic, conceptual, and technical problems. It is suggested that, as a result of these problems, species diversity has become a meaningless concept, that the term be abandoned, and that ecologists take a more critical approach to species-number relations and rely less on information theoretic and other analogies. As multispecific collections of organisms possess numerous statistical properties which conform to the conventional criteria for diversity indices, such collections are not intrinsically arrangeable in linear order along some diversity scale. Several such properties or "species composition parameters" having straightforward biological interpretations are presented as alternatives to the diversity approach. The two most basic of these are simply =the proportion of potential interindividual encounters which is interspecific (as opposed to intraspecific), assuming every individual in the collection can encounter all other individuals, and =the expected number of species in a sample of n individuals selected at random from a collection containing N individuals, S species, and Ni individuals in the ith species.
NuCoSA (Number Cruncher for Community Studies and other Applications) is a user friendly and totally menu controlled program package that allows interactive data analysis. It is written in Pascal, and the application of the results of modern numerical analysis guarantees the high speed of the package. Widely used multivariate methods and specific data analytical techniques applied mainly in ecology are included in the package. -from Author
About twenty years ago, the belief, traditional among ecologists, that complex natural communities are more stable than simple ones was given formal expression in a way that seemed to offer promise of both precise empirical tests and further theoretical development. The elaboration of theoretical models at first yielded gratifying results suggesting reasons why complex ecological systems should indeed be more stable, but these models suffered from questionable analogies and the use of peculiar and unrealistic mathematical representations. The broad scope of the diversity-stability hypothesis, and its particular implications, elevated it to a position importance in practical debates concerning resource management, pest control, and preservation of natural areas. Observational confirmation of the diversity-stability hypothesis never materialized. In this paper we review the development of the diversity-stability hypothesis, evaluate attempts to support or refute it, and suggest an alternate perspective for ...
On Measures of Information and their Characterizations Envi-ronmental Biomonitoring, Assessment, Prediction and Management -Certain Case Studies and Related Quanti-tative Issues Generalized information functions
- J Aczél
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- G P Patil
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Aczél, J. & Daróczy, Z. 1975. On Measures of Information and their Characterizations. Academic Press, New York, NY. Cairns, J., Jr., Patil, G.P. & Waters, W.E. (eds.) 1979. Envi-ronmental Biomonitoring, Assessment, Prediction and Management -Certain Case Studies and Related Quanti-tative Issues. International Co-operative Publishing House, Fairland, MD. Daróczy, Z. 1970. Generalized information functions. Inform. Contr. 16: 36-51.
An overview of diversity
- G P Patil
- C Taillie
Patil, G.P. & Taillie, C. 1979. An overview of diversity. In: Grassle, J.F., Patil, G.P., Smith, W. & Taillie, C. (eds.) Ecological Diversity in Theory and Practice, pp. 3-27.