scholarly journals Traits matter: When rarity means more than abundance to functional diversity

Author(s):  
Thomas J. Trott

Rare species can significantly contribute to ecosystem stability and resiliency. Furthermore, wider taxonomic trees can support a wider range of functional diversity. These ideas with the notion that functional diversity leads to ecosystem resiliency suggest rare species can disproportionately increase taxonomic and functional diversity. To test this hypothesis, functional distinctness was used to estimate functional diversity, and average taxonomic distinctness to evaluate taxonomic diversity for rocky intertidal species assemblages sampled by three surveys separated by years examining a total 41 locations spanning the Gulf of Maine. Fifteen life-history and ecological traits were assigned to the 95 species observed using a total of 90 options. Species were ranked either rare or abundant using incidence. Influence of rarity on functional and taxonomic distinctness was appraised by comparing intact assemblages to ones where rare species (observed once per location) were removed to imitate rare species loss. For intact assemblages, functional and taxonomic distinctness correlated. However, rare species removal significantly decreased functional diversity for some assemblages while taxonomic diversity was less affected. Removal of abundant species produced no significant effects. Results demonstrate rare species can increase functional diversity without necessarily being rare taxonomically. Abundant species exert their effects through their numbers; mere presence makes no difference.

2018 ◽  
Author(s):  
Thomas J. Trott

Rare species can significantly contribute to ecosystem stability and resiliency. Furthermore, wider taxonomic trees can support a wider range of functional diversity. These ideas with the notion that functional diversity leads to ecosystem resiliency suggest rare species can disproportionately increase taxonomic and functional diversity. To test this hypothesis, functional distinctness was used to estimate functional diversity, and average taxonomic distinctness to evaluate taxonomic diversity for rocky intertidal species assemblages sampled by three surveys separated by years examining a total 41 locations spanning the Gulf of Maine. Fifteen life-history and ecological traits were assigned to the 95 species observed using a total of 90 options. Species were ranked either rare or abundant using incidence. Influence of rarity on functional and taxonomic distinctness was appraised by comparing intact assemblages to ones where rare species (observed once per location) were removed to imitate rare species loss. For intact assemblages, functional and taxonomic distinctness correlated. However, rare species removal significantly decreased functional diversity for some assemblages while taxonomic diversity was less affected. Removal of abundant species produced no significant effects. Results demonstrate rare species can increase functional diversity without necessarily being rare taxonomically. Abundant species exert their effects through their numbers; mere presence makes no difference.


2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Marco Milardi ◽  
Anna Gavioli ◽  
Janne Soininen ◽  
Giuseppe Castaldelli

AbstractExotic species invasions often result in native biodiversity loss, i.e. a lower taxonomic diversity, but current knowledge on invasions effects underlined a potential increase of functional diversity. We thus explored the connections between functional diversity and exotic species invasions, while accounting for their environmental drivers, using a fine-resolution large dataset of Mediterranean stream fish communities. While functional diversity of native and exotic species responded similarly to most environmental constraints, we found significant differences in the effects of altitude and in the different ranking of constraints. These differences suggest that invasion dynamics could play a role in overriding some major environmental drivers. Our results also showed that a lower diversity of ecological traits in communities (about half of less disturbed communities) corresponded to a high invasion degree, and that the exotic component of communities had typically less diverse ecological traits than the native one, even when accounting for stream order and species richness. Overall, our results suggest that possible outcomes of severe exotic species invasions could include a reduced functional diversity of invaded communities, but analyzing data with finer ecological, temporal and spatial resolutions would be needed to pinpoint the causal relationship between invasions and functional diversity.


2020 ◽  
Vol 36 (2) ◽  
pp. 47-55
Author(s):  
Julieta Benítez-Malvido ◽  
Ana Paola Martínez-Falcón ◽  
César G. Durán-Barrón

AbstractHuman activities change the biodiversity of ecological communities in at least three dimensions: ecologically, taxonomically and functionally. Gathering information on these three dimensions allows the improvement of biodiversity assessments and the increased understanding of anthropogenic impact on natural communities. In this study, we analysed the spider community associated with the tropical plant Heliconia aurantiaca in two contrasting habitat types: continuous forest and forest fragments in south-eastern Mexico. We examined the foliage, stems and bracts of H. aurantiaca individuals in both habitats. We categorized each spider species according to its behavioural and functional traits. We analysed ecological diversity using Hill numbers, taxonomic distinctness and functional diversity using the FRic index. Overall, we collected a total of 110 spiders, of which 44 individuals from 29 species were found in continuous forests, with 66 individuals from 36 species in forest fragments. We found greater ecological diversity in continuous forest than in fragments. In contrast, we found lower functional diversity in continuous forest than in fragments. Taxonomic diversity showed no significant difference between habitats. Forest fragmentation affected the biodiversity of spiders by disrupting species composition and function, which may lead to other ecological changes such as predator–prey interactions and other aspects of ecosystem functioning.


2020 ◽  
Vol 8 ◽  
Author(s):  
Kaviarasu Munian ◽  
Shahfiz Azman ◽  
Norhazwani Ruzman ◽  
Noor Fauzi ◽  
Alwani Zakaria

Volant and non-volant small mammals from three forest reserves, located inside and outside Selangor State Park, Malaysia, were trapped and documented. A total of five-line transects, each 200 m long and a total of 100 collapsible cage traps, three harp traps and ten mist nets were deployed at each study site to capture rodents and bats species. The presence of 47 species of volant and non-volant mammals was documented with the highest abundant species being Leopoldamys sabanus (n = 61). The Family Vespertilionidae was the most diverse, while Muridae was the most abundant species. Diversity indices have shown forest reserves - Gading Forest Reserve (FR) and Bukit Kutu FR – located in the State Park, have a higher species composition than the impaired adjacent forest reserve, Bukit Tarek FR extension. The taxonomic diversity and taxonomic distinctness of the three forest reserves ranged between 2.433 and 2.610, while the taxonomic distinctness values ranged between 2.638 and 2.748. Even though Gading FR recorded the highest number of species diversity, the Chao 1 diversity estimator and the rarefaction accumulation curve indicated that Bukit Kutu comprised more species. Comparisons between other state parks and national parks in Peninsular Malaysia indicated that Selangor State Park indeed harbours relatively more species of small mammals. Northern Selangor State Park and adjacent forest should be recognised as a conservation priority area, although there are comparatively more species harboured in other regions of the State Park. With the current information on fauna diversity, proper management should be formulated to preserve the existing ecosystems in order to ensure the continuity of fauna diversity in Malaysia.


2016 ◽  
Vol 27 (3-4) ◽  
pp. 47-54
Author(s):  
K. K. Holoborodko ◽  
V. O. Makhina ◽  
K. S. Buchnieva ◽  
O. E. Pakhomov

Floodplain valley of the Dnieper river midstream is a unique natural complex, having a great bìogeographical, ecological, environmental, historical and recreational values. In 1990, the Natural reserve «Dniprovsko-Orilsky» was established within the area. The Natural reserve «Dniprovsko-Orilsky» is environmentally protected site within the Dnipropetrovsk region, Dnipropetrovsk oblast, Ukraine. This reserve occupies part of the Dnieper river valley and marshy and reedy banks of Protovch river (existing bed of Oril river). It was created by Regulation of the Council of Ministers of the USSR of 15 September 1990, No. 262, based on common zoological and ornitological Nature reserves «Taromskì plavni» and «Obukhovskie zaplavy». On the territory of the Natural reserve «Dniprovsko-Orilsky», they were registered 32 Lepidoptera species listed in the List of Threatened Species at different categories (5 species in IUCN Red List ; 18 in Red Data Book of Ukraine; 7 in European Red List of plants and animals endangered on a global scale; 31 in Red Book of Dnipropetrovsk oblast). The main scientific materials were author’s collections from area of research and materials of entomological funds, Department of Zoology and Ecology, Oles Honchar Dnipropetrovsk National University (mostly Memorial Collection of V. O. Barsov). Field surveys covered all the ecosystems basic on size and degree of protection. The author’s researches have conducted over the past decade during annual expeditions to the Reserve. Taxonomic structure of the complex is quite diverse, and represented by all the major families of higher millers and rhopalocera, having protectedstatus. In relation to taxonomy, this complex formed by representatives of five superfamilies (Zyganoidea, Noctuoidea, Bombycoidea, Hesperioidea, Papilionoidea) from 11 families (Zygaenidae, Saturniidae, Sphingidae, Noctuidae Arctiidae Hesperiidae, Papilionidae, Pieridae, Nymphalidae, Satyridae, Lycaenidae). High taxonomic diversity can be explained by unique geographical location of the reserve in azonal conditions of the Dnieper river valley. Such location allows to enter different zoogeographic Lepidoptera groups on the reserve territory. Zoogeographic analysis of species protected within the reserve territory selected 7 basic groups. It was found that most of the globally rare species have Mediterranean origin (39 %); species of Palearctic origin are in second place (22 %); Western Palearctic and Ponto-Kazakh types of areas are same of number of species, and come third (11 %); and others come 17 % (European, Euro-Siberian, and Holarctic). This fauna component is specific due to presence of so-called «northern» species that make up 40 % (representatives of Palearctic, Western Palearctic, Euro-Siberian, European and Holarctic groups). Their existence within the reserve territory is only possible due to development of boreal valley ecosystems. High taxonomic diversity can be explained by unique geographical location of the reserve in azonal conditions of the Dnieper river valley. Such location allows to enter different zoogeographic Lepidoptera groups on the reserve territory. Zoogeographic analysis of species protected within the reserve territory selected 7 basic groups. It was found that most of the globally rare species have Mediterranean origin (39 %); species of Palearctic origin are in second place (22 %); Western Palearctic and Ponto-Kazakh types of areas are same of number of species, and come third (11 %); and others come 17 % (European, Euro-Siberian, and Holarctic). This fauna component is specific due to presence of so-called «northern» species that make up 40 % (representatives of Palearctic, Western Palearctic, Euro-Siberian, European and Holarctic groups). Their existence within the reserve territory is only possible due to development of boreal valley ecosystems.


Author(s):  
Rubén Tarifa ◽  
Carlos Martínez‐Núñez ◽  
Francisco Valera ◽  
Juan P. González‐Varo ◽  
Teresa Salido ◽  
...  

2020 ◽  
pp. 49-55
Author(s):  
António C. Manhice ◽  
Crizalda E. Simões ◽  
Moreno L. Zondane

Diversity of amphibians and reptiles was studied at Chiremera locality in Manica Province, Mozambique. To the best of our knowledge, no herpetofauna study has been done at the Chiremera locality. Globally the herpetofauna of Mozambique remains poorly documented compared to other areas of southern Africa [1]. The study aims to assess the diversity of amphibians and reptiles at Chiremera locality. The data was collected using two techniques: Visual Search and Intercept and pit fall traps. The data was collected in two habitat types: wild areas and human altered areas. We recorded on the wild areas 91 individual of amphibians (18 species, 10 genera and 9 families). The human altered areas had a total of 27 individual amphibians, (4 species, 4 genera and 4 families). Hemisus marmoratus (marbled snout-burrower) was the most abundant species in the two habitats, accounting for 26.3% of all individuals identified. The Shannon winner of amphibians was higher at the wild areas (H '= 2, 1) and lower in the human altered area (H' = 1, 2). A total of 24 individual reptiles were recorded on the wild areas (7 species, 7 genera and 5 families). In contrast to human altered areas we recorded (5 species, 3 Genera, and 3 families). Bitis arietans (puff adder) was the most abundant reptile accounting for 26% of all individuals identified. The Shannon wiener of reptiles was (H’=1, 6) at the wild areas and (H’=1, 5) at the human altered areas. Four rare species namely Hyperolius acuticeps (sharp-headed long reed frog), Hyperolius benguellensis (Benguella long reed frog), Ptychadena subpunctata (spotted ridged frog) all amphibians and Naja mossambica (Mozambique spitting cobra) - reptile were detected during our study. The result of the current study revealed that effect of human altered areas on the richness and abundance of amphibians and reptiles.


Sociobiology ◽  
2016 ◽  
Vol 63 (3) ◽  
pp. 941 ◽  
Author(s):  
Luana Priscila de Carvalho Pereira ◽  
Fábio Souto Almeida ◽  
André Barbosa Vargas ◽  
Marcel Santos de Araújo ◽  
Antônio José Mayhé-Nunes ◽  
...  

The present study aimed at assessing the effects of climate seasonality on poneromorph ants in the Brazilian Amazon, by studying variations in composition, richness, and taxonomic and functional diversity. The study was carried out in the Tapirapé-Aquiri National Forest, southeastern Pará State. We collected poneromorph ants in three areas of native forest with pitfall traps and sardine baits on the ground and vegetation, in two dry and rainy seasons. We collected 46 species of poneromorph ants, which belong to two subfamilies and eleven genera. The species composition, richness and taxonomic diversity did not vary significantly between seasons. There was no significant difference in the frequency of species of functional groups between dry and rainy seasons. There was no significant difference in the average richness and average diversity of functional groups between the dry and rainy seasons. In our study we found no seasonal differences in composition, taxonomic and functional richness and diversity of poneromorph ants in the Amazon, which is useful for future studies that aim at using those ants as bioindicators. In addition, the identification of the species made in the present study has special relevance as it contributes to advance the knowledge of poneromorph ant diversity in the Amazon.


2018 ◽  
Vol 28 ◽  
pp. 39-51 ◽  
Author(s):  
Maria Elina Bichuette ◽  
Eliana do Amaral Gimenez ◽  
Ives Simões Arnone ◽  
Eleonora Trajano

A checklist of bats from Distrito Federal (DF) and Goiás state (GO) and, particularly a single cave (Passa Três cave), located in São Domingos karst area (GO), central Brazil, is presented. Data is based on literature and surveys carried out during 2,000 years. In total, 66 species were recorded, with 30 using caves as shelters. Passa Três cave harbors nine Phyllostomidae species; the most abundant species werePlatyrrhinuslineatus, Lonchorhinaaurita,DesmodusrotundusandCarolliaperspicillata; and the less abundantsTrachopscirrhosus,AnouracaudiferandGlossophagasoricina. Besides, the cave is shelter of two threatened bats -Lonchophylladekeyseri(Endangered category) andLonchorhinaaurita(Vulnerable category), included at Brazilian List of Threatened Fauna, and of a rare species,Lionycterisspurrelli. Passa Três cave shows enough attributes to be considered as a SICOM (Sites of Importance for Conservation of Bats), which would ensure its protection.


Sign in / Sign up

Export Citation Format

Share Document