scholarly journals Breeding bird communities in a morain landscape (Affi, North-Western Venetia): a preliminary survey.

2012 ◽  
Vol 81 (2) ◽  
Author(s):  
Corrado Battisti ◽  
Giuseppe Dodaro

A pilot study was conducted on a moraine hilly landscape (Affi, Verona). We found 43 species of birds overall (40 breeding, two migrants, one exotic species). Mosaics showed the largest absolute number of species (n = 25), the higher mean species richness and the highest diversity index. The croplands and wood fragments, on the contrary, pointed out the lowest absolute number of species, the vineyards showed the mean species richness. These bird communities are typical of conditions with high heterogeneity (mosaic environment) to medium-high level of anthropization, with a species composition characterized by the dominance of common and widespread taxa. We observed individuals of Ptyonoprogne rupestris in atypical environments (anthropized river plain). A stronger research effort is necessary in order to complete the knowledge of breeding bird communities in these particular environments.

2019 ◽  
Author(s):  
Federico Morelli ◽  
Yanina

ContextThe negative association between elevation and species richness is a well-recognized pattern in macro-ecology. ObjectivesThe aim of this study was to investigate changes in functional evenness of breeding bird communities along an elevation gradient in Europe. MethodsUsing the bird data from the EBCC Atlas of European Breeding Birds we estimated an index of functional evenness which can be assumed as a measure of the potential resilience of communities.ResultsOur findings confirm the existence of a negative association between elevation and bird species richness in all European eco regions. However, we also explored a novel aspect of this relationship, important for conservation: Our findings provide evidence at large spatial scale of a negative association between the functional evenness (potential community resilience) and elevation, independent of the eco region. We also found that the Natura2000 protected areas covers the territory most in need of protection, those characterized by bird communities with low potential resilience, in hilly and mountainous areas.ConclusionsThese results draw attention to European areas occupied by bird communities characterized by a potential lower capacity to respond to strong ecological changes, and, therefore, potentially more exposed to risks for conservation.


2016 ◽  
Vol 51 (8) ◽  
pp. 958-966 ◽  
Author(s):  
Anderson Pedro Bernardina Batista ◽  
José Márcio de Mello ◽  
Marcel Régis Raimundo ◽  
Henrique Ferraço Scolforo ◽  
Aliny Aparecida dos Reis ◽  
...  

Abstract: The objective of this work was to analyze the spatial distribution and the behavior of species richness and diversity in a shrub savanna fragment, in 2003 and 2014, using ordinary kriging, in the state of Minas Gerais, Brazil. In both evaluation years, the measurements were performed in a fragment with 236.85 hectares, in which individual trees were measured and identified across 40 plots (1,000 m2). Species richness was determined by the total number of species in each plot, and diversity by the Shannon diversity index. For the variogram study, spatial models were fitted and selected. Then, ordinary kriging was applied and the spatial distribution of the assessed variables was described. A strong spatial dependence was observed between species richness and diversity by the Shannon diversity index (<25% spatial dependence degree). Areas of low and high species diversity and richness were found in the shrub savanna fragment. Spatial distribution behavior shows relative stability regarding the number of species and the Shannon diversity index in the evaluated years.


2020 ◽  
Author(s):  
E Sebastián-González ◽  
JM Barbosa ◽  
JM Pérez-García ◽  
Z Morales-Reyes ◽  
F Botella ◽  
...  

© 2019 John Wiley & Sons Ltd Understanding the distribution of biodiversity across the Earth is one of the most challenging questions in biology. Much research has been directed at explaining the species latitudinal pattern showing that communities are richer in tropical areas; however, despite decades of research, a general consensus has not yet emerged. In addition, global biodiversity patterns are being rapidly altered by human activities. Here, we aim to describe large-scale patterns of species richness and diversity in terrestrial vertebrate scavenger (carrion-consuming) assemblages, which provide key ecosystem functions and services. We used a worldwide dataset comprising 43 sites, where vertebrate scavenger assemblages were identified using 2,485 carcasses monitored between 1991 and 2018. First, we evaluated how scavenger richness (number of species) and diversity (Shannon diversity index) varied among seasons (cold vs. warm, wet vs. dry). Then, we studied the potential effects of human impact and a set of macroecological variables related to climatic conditions on the scavenger assemblages. Vertebrate scavenger richness ranged from species-poor to species rich assemblages (4–30 species). Both scavenger richness and diversity also showed some seasonal variation. However, in general, climatic variables did not drive latitudinal patterns, as scavenger richness and diversity were not affected by temperature or rainfall. Rainfall seasonality slightly increased the number of species in the community, but its effect was weak. Instead, the human impact index included in our study was the main predictor of scavenger richness. Scavenger assemblages in highly human-impacted areas sustained the smallest number of scavenger species, suggesting human activity may be overriding other macroecological processes in shaping scavenger communities. Our results highlight the effect of human impact at a global scale. As species-rich assemblages tend to be more functional, we warn about possible reductions in ecosystem functions and the services provided by scavengers in human-dominated landscapes in the Anthropocene.


2015 ◽  
Vol 7 (15) ◽  
pp. 8272 ◽  
Author(s):  
Girish Gogoi ◽  
Vipin Parkash

<p>Hollongapar Gibbon Wildlife Sanctuary is comprised of five distinct compartments.  A total of 138 species of gilled mushrooms belonging to 48 genera, 23 families, five orders of the class Agaricomycetes, division Basidiomycota, have been collected and analyzed. The order Agaricales was was found with the highest number of species (113), followed by Russulales (14), Polyporales (5), Cantharellales (4) and Boletales (2). The species <em>Coprinellus disseminatus </em>and <em>Megacollybia rodmani</em> have shown the highest (8.26) and the lowest density (0.05), respectively.  A total of 24 species, e.g., <em>Termitomyces albuminosus, Marasmius curreyi, Marasmiellus candidus, Leucocoprinus medioflavus, Mycena leaiana, Hygrocybe miniata, Collybia chrysoropha, Gymnopus confluens</em> were common with frequency percentage of 11.9, whereas <em>Megacollybia rodmani</em> with less frequency percentage (2.4) was found only in few quadrates of the sanctuary.  The highly abundant species were <em>Termitomyces medius</em> (91.7) and <em>Coprinellus disseminatus </em>(86.8), and less abundant species were <em>Psilocybe wayanadensis</em> (1.0) and <em>Lepiota</em> sp. (1.0) in the study site.  The order of the species richness index (<em>R</em>) compartment wise was 2&gt;3&gt;4&gt;5&gt;1. Both the Shannon diversity index and Simpson diversity index of agarics was maximum (1.88, 0.98) in compartment 2, whereas minimum (1.72, 0.95) in compartment 1 and 5, respectively.  Moreover, the compartment 2 was found very much similar with compartment 3 and very less similar with compartment 1.</p><div> </div>


2016 ◽  
Vol 8 (1) ◽  
pp. 357-366 ◽  
Author(s):  
Eddy Yusron

A study on Echinoderms community structure in marine national parks of Wakatobi, Southeast Sulawesi was conducted in six locations, i.e., Waha Beach, Coastal Sombo, Beach Houses, Beach Kapota, Banakawa beach, and Umala beach in October 2013. All of the six parks were located the Wakatobi territorial waters with coordinates of 5°06'25" S and 123°124'10 E. The results showed of 18 species of echinoderms representing six different types of Asteroidea, two types of Ophiuroidea, six types of Echinoidea, and four types of Holothuroidea. Group of starfish or Asteroidea was the most prominent on seagrass area. Based on the six transects sites, it turned out that the group of starfish (Asteridea) occupied a relatively high level of species richness. From the quantitative analysis values, we obtained diversity index (H) of 1.105 in Sombu, the highest evenness index (J) of 0.989 was found in Umala, and the highest species richness index values (D) of 0.132 was obtained in kapota. It seemed that all echinoderm groups were generally like seagrass microhabitat (12 types). While, sand and dead coral habitats were only occupied by 8 (eight) echinoderm groups. Keywords: echinoderms, diversity, Wakatobi, Southeast Sulawesi


Paleobiology ◽  
2016 ◽  
Vol 42 (2) ◽  
pp. 269-288 ◽  
Author(s):  
Michael Foote ◽  
Kathleen A. Ritterbush ◽  
Arnold I. Miller

AbstractWe explore the relationships among the geographic ranges of genera, the ranges and positions of their constituent species, and the number of species they contain, considering variation among coeval genera and changes within genera over time. Measuring range size as the maximal distance, or extent, between occurrences within a taxon, we find that the range of the most widespread species is a good predictor of the range of the genus, and that the number of species is a better predictor still. This analysis is complicated by a forced correlation: the range of a genus must be at least as large as that of each of its constituent species. We therefore focus on a second measure of range, the mean squared distance, or dispersion, of occurrences from the geographic centroid, which, by analogy to the analysis of variance, allows the total dispersion of a genus to be compared to the mean within-species dispersion and the dispersion among species centroids. We find that among-species dispersion is the principal determinant of genus dispersion. Within-species dispersion also plays a major role. The role of species richness is relatively small. Our results are not artifacts of temporal variation in the geographic breadth of sampled data. The relationship between changes in genus dispersion and changes in within- and among-species dispersion shows a symmetry, being similar in cases when the genus range is expanding and when it is contracting. We also show that genera with greater dispersion have greater extinction resistance, but that within- and among-species dispersion are not demonstrable predictors of survival once the dispersion of the genus is accounted for. Thus it is the range of the genus, rather than how it is attained, that is most relevant to its fate. Species richness is also a clear predictor of survival, beyond its effects on geographic range.


1987 ◽  
Vol 3 (2) ◽  
pp. 109-118 ◽  
Author(s):  
E. N. Chidumayo

ABSTRACTMiombo woodland in Zambia is divided into wetter and drier types by the 1100 mm mean rainfall isohyet. In the present study two wetter (Northern, Northwestern) and three drier (Central, Eastern, Western) miombo subtypes were recognized.A survey of the woody flora of 94 old-growth and 58 coppice stands in the five miombo subtypes revealed some significant differences in species diversity among them. The floristic differentiantion of miombo subtypes was best achieved by the use of the Shannon species diversity index (H′) and species density (number of species 0.1 ha−1 or 0.4 ha−1). H′ in miombo decreased from 2.247 in Northwestern to 2.136 in Northern, 2.052 in Eastern, 1.918 in Central and 1.824 in Western subtypes. Although species density was not significantly different between wetter miombo subtypes, this decreased in a similar fashion from 18.78 0.1 ha−1 in Northwestern to 18.30 in Northern, 16.65 in Eastern, 14.79 in Central and 12.29 in Western subtypes. The low species diversity in Western drier miombo was attributed to the combined effects of low soil fertility and rainfall.Although the mean number of species per 0.1 ha plot was higher in coppice samples, species richness (d) and index of diversity (H′) were lower than in old-growth samples. These results indicate lower species diversity in regenerating miombo. The dynamic aspects of species structure should therefore be considered in the future conservation of biological diversity in miombo woodland.


2021 ◽  
Vol 16 (3) ◽  
Author(s):  
Jarnail Singh ◽  
Sunil Bhandari ◽  
M S Bisht

The avian diversity of Oak mixed forest in Pauri Garhwal district of Uttarakhand was studied during October 2019 to March 2020. Two strands of oak mixed forest located at different sites at 29º 22’-29º 75’ North and 78º, 10’ -78º,80’ East (1750 masl) were selected. Regular field survey was carried out during the morning and evening hours at each site. A total of 63 species of birds belonging to 07 orders and 31 families were recorded. The average bird diversity index H ¯was 3.202. The species richness was observed around 7.27 and species evenness was 0.72. The highest number of species was recorded at Ransi Oak mixed forest (63) and lowest number of bird species were recorded in Teka Oak mixed forest (60).


2020 ◽  
Vol 13 ◽  
pp. 194008292090697
Author(s):  
Mélanie A. Tchoumbou ◽  
Elikwo F. N. Malange ◽  
Claire T. Tiku ◽  
Brice Tibab ◽  
Jerome Fru-Cho ◽  
...  

Birds are crucial in maintaining the balance of many ecosystems and provide various ecological services. Understanding their sensitivity to human disturbances should be prioritized in understudy areas for effective conservation practices. Using mist nets, this study characterized mostly understory bird communities (insectivorous, frugivorous, granivorous, and nectarivorous birds) in three habitat types (pristine forest, selectively logged forest, and young oil palm plantation) in the Talangaye rainforest, Southwest Cameroon. A total of 845 birds belonging to 27 families and 85 species were recorded in the three habitats after 294 h of mist netting. Overall, the mist-netted community was largely dominated by insectivores, followed by frugivores, nectarivores, granivores, and carnivores. Although mean species richness, abundance, and Simpson diversity index did not vary significantly among habitat types, mean species abundance and diversity index decreased in selectively logged forest and young oil palm plantation and species richness increased in both habitats. The species richness, abundance, and diversity index for insectivorous and frugivorous birds were lowest in the young oil palm plantations. For granivores, species richness and abundance increased following selective logging and the establishment of oil palm plantation. The highest mean species richness and diversity index in nectarivores were recorded in the young oil palm plantations. The study showed that selective logging and establishment of oil palm plantation had variable effects on the bird communities in the Talangaye rainforest. Also, the frugivorous birds appeared to be more sensitive to both types of disturbances, while the insectivores were more sensitive to habitat loss/conversion.


2014 ◽  
Vol 23 (3) ◽  
pp. 343-347 ◽  
Author(s):  
Maria Danielle Figueiredo Guimarães Hoshino ◽  
Érico Melo Hoshino ◽  
Marcos Tavares-Dias

This study was the first investigation of communities and infracommunities of parasites of Hemibrycon surinamensis. All the fish collected in a tributary of the Amazon river were parasitized by one or more parasite species. The Brillouin diversity index (HB) was 0.46 ± 0.28 and the mean species richness was 3.5 ± 1.2 parasites per host. A total of 14,734 parasites were collected, including Ichthyophthirius multifiliis and Piscinoodinium pillulare (Protozoa); Jainus hexops and Tereancistrum sp. (Monogenoidea); Ergasilus turucuyus and Argulus sp. (Crustacea); metacercariae of Derogenidae gen. sp.; metacercariae and adults of Genarchella genarchella (Digenea); and Cucullanus larvae and Contracaecum larvae (Nematoda). The dominant parasite was I. multifiliis, followed by P. pillulare. The parasites showed aggregated dispersion, except for E. turucuyus, which had random dispersion. The condition factor (Kn) indicated that the parasitism levels had not affected host body condition. The high levels of infection observed were due to host behavior, and this was discussed. This was the first report of I. multifiliis, P. pillulare, Argulus sp., E. turucuyus, G. genarchella, J. hexops and Tereancistrum sp. in H. surinamensis, and it expanded the occurrence of E. turucuyus and G. genarchella to the eastern Amazon region.


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