species rarity
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2021 ◽  
Author(s):  
Shukrullo Foziljonov

In the Republic of Uzbekistan, 13 species of representatives of this family are considered rare and are listed in the Red Book, of which 4 species (Gamanthus ferganicus, Anthochlamys tianshanica, Salsola drobovii, Halimocnemis lasiantha) are distributed in the Fergana Valley, mainly in the Fergana region. In this article, it is precisely these 4 species' rarity that have been studied theoretically comparing to each other, and that representatives of the family, which are widely distributed mainly in the steppe region, have been preserved in the mountainous area and have an idea of the growth environment.


2021 ◽  
pp. 143-153
Author(s):  
Christian Molls

Abstract The current reliability of species identifications by the Nature Identification API (NIA) of the app ObsIdentify is tested with a Coleoptera (Insecta) sample set from Germany. Seventy-five photographic beetle records taken with a smartphone camera under “average user” conditions are analysed in terms of correctness of the app’s identification result on various taxonomic levels, the displayed confidence level of the identification and the time until validation of the results. More than 60% of samples were identified correctly at the species level, but only 53% were validated within a month. The mechanisms by which users can upload pictures of their observations to be identified by the artificial intelligence and the validation process by experts are briefly explained. Regional specifics and further opportunities for data usage as well as currently existing problems are discussed and improvements are suggested. The expert validation of records is identified as a huge quality advantage of the Obs-Services. They are generally found to be a promising tool for lay people and professional institutions, despite still existing deficiencies such as identification failure in mutilated specimens, cryptic and rare species, doubtful species rarity ratings as well as the still insufficient capacity of validation. Experts and institutions are encouraged to volunteer as validators and collaborators.


Biologia ◽  
2021 ◽  
Author(s):  
Enikő T-Krasznai ◽  
Viktória B-Béres

AbstractInternational and national protection strategies and directives focus mainly on macroscopic organism and attempt to maintain their endangered habitats. However, microscopic communities are also threatened by decreasing biodiversity and many species including freshwater algae can disappear without even knowing they were present in the habitat. Defining rarity of microscopic taxa is not easy. The species’ rarity is based on detailed knowledge of distribution and abundance of species. But only limited information is available about rare algal species especially in a given ecoregion. Reducing the data gaps, here, we present altogether 20 phytoplankton taxa rare in Hungary: three species of Chlorophyceae, eight species of Trebouxiophyceae, two taxa of Euglenophyceae, one-one species of Cyanobacteria, Bacillariophyceae and Mediophyceae and three species of Xanthophyceae. One of them, the Cylindrotheca gracilis is on the Hungarian Red List. Physical and ecological characteristics of standing waters where these species were found as well as their former occurrence all over the world are also reviewed.


Forests ◽  
2020 ◽  
Vol 12 (1) ◽  
pp. 27
Author(s):  
Giorgio Brunialti ◽  
Paolo Giordani ◽  
Sonia Ravera ◽  
Luisa Frati

(1) Research Highlights: The work studied the beta diversity patterns of epiphytic lichens as a function of their reproductive strategies in old-growth and non-old growth forests from the Mediterranean area. (2) Background and Objectives: The reproductive strategies of lichens can drive the dispersal and distribution of species assemblages in forest ecosystems. To further investigate this issue, we analyzed data on epiphytic lichen diversity collected from old-growth and non-old growth forest sites (36 plots) located in Cilento National Park (South Italy). Our working hypothesis was that the dispersal abilities due to the different reproductive strategies drove species beta diversity depending on forest age and continuity. We expected a high turnover for sexually reproducing species and high nestedness for vegetative ones. We also considered the relationship between forest continuity and beta diversity in terms of species rarity. (3) Materials and Methods: we used the Bray–Curtis index of dissimilarity to partition lichen diversity into two components of beta diversity for different subsets (type of forest, reproductive strategy, and species rarity). (4) Results: The two forest types shared most of the common species and did not show significant differences in alpha and gamma diversity. The turnover of specific abundance was the main component of beta diversity, and was significantly greater for sexually reproducing species as compared to vegetative ones. These latter species had also the least turnover and greater nestedness in old-growth forests. Rare species showed higher turnover than common ones. (5) Conclusions: Our results suggest that sexually reproducing lichen species always have high turnover, while vegetative species tend to form nested assemblages, especially in old-growth forests. The rarity level contributes to the species turnover in lichen communities. Contrary to what one might expect, the differences between old-growth and non-old growth forests are not strong.


Oryx ◽  
2020 ◽  
pp. 1-6
Author(s):  
María M. Torres-Martínez ◽  
Héctor E. Ramírez-Chaves ◽  
Elkin A. Noguera-Urbano ◽  
Fernando C. Passos

Abstract The brown hairy dwarf porcupine Coendou vestitus is a poorly studied Andean species endemic to Colombia. Its current Red List category is contradictory: globally it is categorized as Data Deficient but in Colombia it is categorized as Vulnerable. This contradiction has limited the implementation of conservation programmes. We evaluate the level of rarity of the species and provide consolidated information for a new assessment of its Red List status. We reviewed literature, photographs, and voucher specimens in natural history collections. Using the confirmed records, we estimated the extent of occurrence (EOO) based on the minimum convex polygon and the area of occupancy (AOO) summing the area of grid squares occupied by the species. We found that C. vestitus is very rare, with a small range, low estimated population density, occurrence in only one habitat type and small body size. The species has an EOO of 3,323 km2 and an AOO of 24 km2, based on six confirmed localities, all on the western slopes of the Eastern Cordillera, in the central Andean region of Colombia. Based on the species' rarity, restricted distribution, and threats to its natural habitat, we recommend its categorization as Endangered on the IUCN Red List. This will help delineate research and conservation efforts for this porcupine, which has a highly restricted range and inhabits the threatened Andean forest.


2020 ◽  
Vol 3 ◽  
pp. 29
Author(s):  
Ghislain Comlan Akabassi ◽  
Elie Antoine Padonou ◽  
Achille Ephrem Assogbajo ◽  
Noël Zirihi Guede

Background: Picralima nitida (Apocynaceae) is an important African medicinal plant species. It is frequently used in traditional medicine and pharmaceutical industries for manufacture of drugs against infectious diseases, malaria, diabetes and cancer. Despite its important, the species can be rare, especially in the Dahomey Gap (in contrast to the Guineo-Congolese region). There is also a controversy on its distribution. Without knowing the drivers of plant species rarity it is impossible to address the issue of the controversy of its distribution and unsustainable use as well as safeguarding endogenous knowledge of its uses.  Methods: Ethnobotanical surveys were conducted in the Dahomey Gap with 120 informants randomly interviewed. A literature review of scientific papers and books was used to provide information on the uses, distribution and threats of the species in the Guineo-Congolese region. Results: The results revealed that P. nitida products were more expensive in the Dahomey Gap than the Guineo-Congolese region. All parts of the species were collected and used for 34 treatments. The species had low density and distribution in Dahomey Gap compared to the Guineo-Congolese region. Conclusions: P. nitida is used across its distribution areas with important economic values. Adapted management strategies are needed for the sustainable use and conservation of the species..


2020 ◽  
Vol 10 (17) ◽  
pp. 9037-9047
Author(s):  
Thomas P. Wiegand ◽  
Braley Gentry ◽  
Zachary McCoy ◽  
Craig Tanis ◽  
Hope Klug ◽  
...  

Plant Ecology ◽  
2020 ◽  
Vol 221 (11) ◽  
pp. 1045-1067
Author(s):  
Vera Margreiter ◽  
Konrad Pagitz ◽  
Christian Berg ◽  
Patrick Schwager ◽  
Brigitta Erschbamer

Abstract Storing seeds in seed banks is an effective way to preserve plant diversity and conserve species. An essential step towards a valuable conservation is the validation of germination. This study presents a germination screening of seeds from 255 species of the European Eastern Alps, which were to be stored at the Millennium Seed Bank (Kew, UK). The final germination percentage (FGP) was determined using a standard protocol in the laboratory. Species were classified according to species rarity, plant community, occurrence at elevation belts, bedrock types, as well as CSR strategies, and further, seed mass was examined. We could not find statistically significant differences of FGP within these classes, but 74.9% of all tested species germinated using the standard protocol, and half of them had FGP ≥ 20.1–100%. A treatment with gibberellic acid enhanced the germination in half of the species to which this treatment was applied. Common families in alpine regions, i.e. Asteraceae, Poaceae and Saxifragaceae were highlighted in terms of their germination behaviour. The results provide an evaluation of the application of standard protocols to a broad Alpine species pool on the one hand, and on the other hand, provide ecological insights of the species tested. Germination is not only one of the most important events of the reproductive cycle of plants but could also be a key feature in species' responses to changing environmental conditions.


Author(s):  
Mike Brock ◽  
Iain Fraser ◽  
Cherry Law ◽  
Simon Mitchell ◽  
David L. Roberts

PeerJ ◽  
2020 ◽  
Vol 8 ◽  
pp. e8373
Author(s):  
Fabio Albuquerque ◽  
Yaiyr Astudillo-Scalia

Because the distribution of most of the species is poorly known, conservationists use surrogates to help maximize the representation level of all species. Historically, species richness has been used to calculate the importance of priority areas for conservation, but several studies revealed sites with high species richness often fail to determine the smallest number of sites that will protect the highest number of species. Rarity, however, has played a prominent role in safeguarding planning units. While the performance of rarity has been previously assessed in terrestrial systems, we tested the hypothesis that rarity of a site can be used as a measure of the importance of a site to a conservation network in marine ecosystems. We used the presence data (at a 1-degree resolution) to calculate five rarity indices of fish diversity at a global extent and compared the results to those obtained by using species richness and site complementarity. Our objectives were to: (1) determine if rarity indices can be used as surrogates of fish biodiversity by representing the highest number of species in the smallest number of sites; and (2) determine if the effectiveness of these indices to represent fish biodiversity is impacted by the metric used to define rarity. Results indicate that rarity could be an effective surrogate for marine fishes, as most results showed a mean of 100% effectiveness. In the context of marine biodiversity conservation, results show that rarity indices could be considered affordable and feasible surrogates of species representation, with the most significant benefit to those areas of the world that are in most need to access alternative tools. Results also open a new area of collaboration between biogeography and marine conservation biology since planners can use biogeographical patterns of rarity to enhance the performance of the current protected area network.


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