scholarly journals Abundance-dependent effects of neighbourhood dissimilarity and growth rank reversal in a neotropical forest

2018 ◽  
Vol 285 (1876) ◽  
pp. 20172878 ◽  
Author(s):  
Yuxin Chen ◽  
María Natalia Umaña ◽  
María Uriarte ◽  
Shixiao Yu

Why tropical forests harbour an exceptional number of species with striking differences in abundances remains an open question. We propose a theoretical framework to address this question in which rare species may have different extirpation risks depending on species ranks in tree growth and sensitivities to neighbourhood interactions. To evaluate the framework, we studied tree growth and its responses to neighbourhood dissimilarity (ND) in traits and phylogeny for 146 species in a neotropical forest. We found that tree growth was positively related to ND, and common species were more strongly affected by ND than rare species, which may help delay dominance of common species. Rare species grew more slowly at the community-wide average ND than common species. But rare species grew faster when common species tended to dominate locally, which may help reduce extirpation risk of rare species. Our study highlights that tree growth rank among species depends on their responses to neighbourhood interactions, which can be important in fostering diversity maintenance in tropical forests.

2001 ◽  
Vol 17 (3) ◽  
pp. 353-369 ◽  
Author(s):  
IRENE LINDBLAD

The influence of a rainfall gradient on the distribution and species richness of some groups of wood-inhabiting basidiomycetes was explored in Costa Rican tropical forests. The relationships between these fungi and wood size and decay stage were also studied. Basidiocarps of all poroid and some corticoid fungi were recorded in three plots of 30 logs in each of dry, moist, and wet forests. The logs were surveyed three times during one year, covering all seasons. The species richness gradient was inversely related to the rainfall gradient, with most species in the dry forest (51), least in the wet forest (37), and intermediate in the moist forest (44). A total of 102 species were identified. Only six species occurred at all three sites. Two of the four most common species were new to science. The composition of wood-inhabiting fungal species in the dry forest varied from both the moist and the wet forest, while species composition in the two latter forest types was difficult to distinguish. Both frequent and rare species utilized the different decay stages as expected from availability of substrate. Perennials and rare species tended to occur on large logs in the dry forest, while all species tended to occur on large logs in the moist forest, but not in the wet forest.


2006 ◽  
Vol 38 (4) ◽  
pp. 373-382 ◽  
Author(s):  
Juri NASCIMBENE ◽  
Stefano MARTELLOS ◽  
Pier Luigi NIMIS

135 infrageneric taxa of epiphytic lichen were found in 20 stands of tree-line forests of the Central-Eastern Italian Alps. Three forest types were considered: (1) late successional stands with several large trees, (2) pioneer stands on abandoned pastures without large trees, and (3) open and grazed stands. They were compared on the basis of four main criteria: (1) species richness, (2) number of rare species, (3) number of species that are exclusive to the subalpine belt in Italy, and (4) number of species that are exclusive to the Alps in Italy. Species richness is higher in the late successional stands, which also host a higher share of rare and exclusive species. The total number of rare species per site is correlated with the total number of species, as well as with the number of common species, and with the total number of macrolichens. Rare macrolichens are correlated with common macrolichens. Two main groups of target species with decreasing conservation priority are identified. Letharia vulpina is suggested as signal species for sites worthy of conservation. The guild of macrolichens may be used as an indicator of both species richness and of the occurrence of rare species.


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.


Zootaxa ◽  
2021 ◽  
Vol 4974 (2) ◽  
pp. 201-257
Author(s):  
MOLLY SCHOOLS ◽  
S. BLAIR HEDGES

Lizards of the family Diploglossidae occur in moist, tropical forests of Middle America, South America, and Caribbean islands. Our analyses based on new molecular and morphological data indicate that the widely distributed genera Celestus Gray, 1839 and Diploglossus Wiegmann, 1834 are paraphyletic. We restrict the former to Caribbean islands and the latter to South America and Caribbean islands. We assign species in Middle America, formerly placed in Celestus and Diploglossus, to Advenus gen. nov., Mesoamericus gen. nov., and Siderolamprus Cope, 1861. We assign species on Caribbean islands, formerly placed in Celestus, to Caribicus gen. nov., Comptus gen. nov., Celestus, Panolopus Cope, 1862, Sauresia Gray, 1852, and Wetmorena Cochran, 1927. Our phylogenetic tree supports three major clades in the family: Celestinae subfam. nov. (Advenus gen. nov., Caribicus gen. nov., Comptus gen. nov., Celestus, Panolopus, Sauresia, and Wetmorena), Diploglossinae (Diploglossus and Ophiodes Wagler, 1828), and Siderolamprinae subfam. nov. (Mesoamericus gen. nov. and Siderolamprus). Our timetree indicates that the diploglossid lineage originated in the early Cenozoic and established three major centers of diversification in the Americas: Middle America (siderolamprines and one celestine), South America (diploglossines), and Caribbean islands (celestines and diploglossines). The majority of threatened species are on Caribbean islands, with the major threats being deforestation and predation by the introduced mongoose. Molecular and morphological data indicate that there are many undescribed species in this family of lizards. 


2021 ◽  
Vol 55 (2) ◽  
pp. 361-377
Author(s):  
N. I. Borzov ◽  
F. M. Bortnikov ◽  
A. V. Matveev ◽  
V. I. Gmoshinskiy

The results of the first study of the species diversity of myxomycetes of the Rdeysky State Nature Reserve are presented. The 201 field specimens of sporophores belonging to 56 morphospecies from 27 genera, ten families, and six orders were collected from September 30 to October 5, 2020. Fifty-two species of these were new for the Novgorod Region. The most common species at the reserve were Arcyria affinis, Hemitrichia calyculata, Lycogala epidendrum, Metatrichia vesparia, Physarum album, Trichia decipiens, and T. varia. Additionally, detailed morphological descriptions of two rare species Amaurochaete trechispora and Trichia crateriformis are given.


2016 ◽  
Vol 371 (1694) ◽  
pp. 20150269 ◽  
Author(s):  
Santiago Soliveres ◽  
Peter Manning ◽  
Daniel Prati ◽  
Martin M. Gossner ◽  
Fabian Alt ◽  
...  

Species diversity promotes the delivery of multiple ecosystem functions (multifunctionality). However, the relative functional importance of rare and common species in driving the biodiversity–multifunctionality relationship remains unknown. We studied the relationship between the diversity of rare and common species (according to their local abundances and across nine different trophic groups), and multifunctionality indices derived from 14 ecosystem functions on 150 grasslands across a land-use intensity (LUI) gradient. The diversity of above- and below-ground rare species had opposite effects, with rare above-ground species being associated with high levels of multifunctionality, probably because their effects on different functions did not trade off against each other. Conversely, common species were only related to average, not high, levels of multifunctionality, and their functional effects declined with LUI. Apart from the community-level effects of diversity, we found significant positive associations between the abundance of individual species and multifunctionality in 6% of the species tested. Species-specific functional effects were best predicted by their response to LUI: species that declined in abundance with land use intensification were those associated with higher levels of multifunctionality. Our results highlight the importance of rare species for ecosystem multifunctionality and help guiding future conservation priorities.


1987 ◽  
Vol 82 (1) ◽  
pp. 119-124 ◽  
Author(s):  
M. Dora Feliciangeli

A study on the ecology of phlebotomine sandfly fauna in a restricted focus of cutaneous leishmaniasis in northern Venezuela was undertaken in order to investigate the species responsible for the transmission. The study area and catching methods for phlebotomine sandflies are described. A total of 9,061 females and 1,662 males were collected during a year-term study. 12 species of Lutzomya and 1 species of Brumptomya sp. were identified. Absolute and relative abundance and ocurrence for each species were determined. The rel ative occurrence allowed to distinguish the common species, viz. L. panamensis, L. ovallesi, L. gomezi, L. tinidadensis, L. atroclavata, L. cayennensis, L. shannoni and L. olmeca bicolor from the rare species vis., L. punctigeniculata, L. rangeliana, L. evansi and L. dubitans. General comments on the species composition of the sandfly fauna in this locality are made.


2021 ◽  
Vol 4 ◽  
Author(s):  
Roger Chambi-Legoas ◽  
Daigard Ricardo Ortega Rodriguez ◽  
Francisco de Marques de Figueiredo ◽  
Joel Peña Valdeiglesias ◽  
Percy Amílcar Zevallos Pollito ◽  
...  

Context: Gold mining is the most destructive activity in the natural forests of the Madre de Dios region in the southeastern Peruvian Amazon. Understanding the natural regeneration process of these degraded areas is necessary to develop forest restoration projects in such conditions.Aims: We aimed to evaluate forest recovery and identify the successional and structure patterns of vegetation governing natural regeneration over time.Methods: Structure, composition, richness, diversity, and successional status were evaluated in abandoned artisanal gold mine areas in Madre de Dios, southeastern Peru. Vegetation data were recorded in 61 plots of 250 m2 established in five sites varying from 1 to 19 years of abandonment. Vegetation in abandoned areas was compared with six undisturbed forests evaluated in previous inventories.Results: In the mining lands, tree density and basal area recovered quickly, while species richness and composition were slow. Forest recovery is an initial stage of transition from pioneer to early secondary species until at least 19 years after abandonment. The most abundant and frequent species were the fast-growing species Ochroma pyramidale and Cecropia engleriana. These species could be considered potential candidates to promote restoration plans. Pioneer species represented 63% of the number of species in plots of 1–4 years, 57% in plots of 5–7 years, and 50% in plots of 8–19 years. Early and late secondary species represented 34 and 16%, respectively, of the number of species in plots of 8–19 years. Abandoned mining and reference plots present less than 5% of species in common.Conclusion: Our results highlight a slow natural regeneration process in areas for up to 19 years after gold mining. Species from different successional statuses were identified as potential candidates for recovering vegetation in such areas. Our findings may have important implications for further research focusing on the ecological restoration in tropical forests severely degraded by gold mining.


Author(s):  
J. Mauchline

Schistomysis kervillei (G. O. Sars) is a common species in Loch Ewe, Gairloch and Gruinard Bay in north-west Scotland and a rare species in the Firth of Clyde. It breeds throughout the year but most intensely in the spring and summer, to produce a spring and summer generation of young. The maximum number of young found in a marsupium was 47. The species is omnivorous. Its biology is briefly compared with that of S. spiritus (Norman) and S. ornata (G. O. Sars).


2017 ◽  
Vol 26 (5) ◽  
pp. 513-523 ◽  
Author(s):  
Glenda Yenni ◽  
Peter B. Adler ◽  
S. K. Morgan Ernest

Sign in / Sign up

Export Citation Format

Share Document