scholarly journals Environmental filters and biotic interactions drive species richness and composition in ecotone forests of the northern Brazilian Amazonia

2021 ◽  
Vol 16 (2) ◽  
pp. 229-244
Author(s):  
Williamar Rodrigues Silva ◽  
Pedro Aurélio Costa Lima Pequeno ◽  
Hugo Leonardo Sousa Farias ◽  
Valdinar Ferreira Melo ◽  
Carlos Darwin Angulo Villacorta ◽  
...  
Keyword(s):  
Species Richness ◽  
Biotic Interactions ◽  
Single Species ◽  
Permanent Plots ◽  
Environmental Filters ◽  
Brazilian Amazonia ◽  
Edaphic Conditions ◽  
Tree Community ◽  
Tree Communities ◽  
Edaphic Gradient

The structure of tree communities in tropical forests depends on environmental filters and biotic interactions such as competition and facilitation. Many ecotone forests in Northern Amazonia are intriguingly populated by tree assemblages characterized by distinct abundances of a single species, Peltogyne gracilipes (Leguminosae). It is unclear whether this pattern solely reflects environmental filters or also antagonistic interactions among species with similar habitat requirements. The aim of this study was to determine the response of species richness and composition to environmental filters, and analyze the role of P. gracilipes in structuring tree communities in ecotone forest areas of the Northern Brazilian Amazonia. We sampled 129 permanent plots along a hydro-edaphic gradient. All arboreal individuals with stem diameter ≥10 cm were measured and identified. Multiple regressions were performed to test the effects of environmental filters, and abundance of P. gracilipes on the tree species richness and composition. Species richness and composition responded to the same filters which, in turn, affected species composition directly and indirectly, through the abundance of P. gracilipes. Our results indicate that both abiotic filters and biotic interactions shape the studied tree communities. P. gracilipes can be considered an indicator species of hydro-edaphic conditions, but also is itself a driver of tree community structure.

scholarly journals Shift in the Spatio-Temporal Natural Fruiting of Boletes in West African Woodlands: the Key Role of the Soil Moisture

2020 ◽  
Author(s):  
Akotchayé Sylvestre Badou ◽  
Roel D. Houdanon ◽  
Kassim I. Tchan ◽  
D.M.T. Apollon Hègbè ◽  
Nourou Soulemane Yorou
Keyword(s):  
Species Richness ◽  
Soil Moisture ◽  
Ectomycorrhizal Fungi ◽  
Linear Models ◽  
Positive Influence ◽  
Permanent Plots ◽  
Data Logger ◽  
Fresh Biomass ◽  
Natural Production ◽  
Spatio Temporal

Abstract Background: The ectomycorrhizal fungi display strong fluctuations during the mycological season. However, how abiotic parameters affect the fruiting sequences of ectomycorrhizal fungi and also the direction and extent of this effect are not yet tapped adequately. The present study seeks to assess the microclimate effect on the natural production of boletes. Nine permanent plots of 2500 m2 (50m x 50m) split into 25 subplots of 100 m2 (10m x 10m) were installed in three different vegetation dominated respectively by Isoberlinia doka, Isoberlinia tomentosa and Uapaca togoensis. Microclimatic parameters were recorded each 30 minutes throughout by mean of a Micro Station Data Logger - H21-002 the mycological seasons. Each plot was surveyed twice a week (from May to October) over three years (2015, 2016 and 2017) to record the presence/absence of fruit bodies and fresh biomass of boletes. To evaluate the effect of time and microclimate variables on natural production, we used mixed effects and generalized linear models using R version 3.5.3. Results: In total, during the three years (2015, 2016 and 2017), we recorded 14 species of boletes. Species richness does not change over time (P > 0.05). In addition, fresh biomass varies within years and vegetation (P < 0.05). The combination of year and month of collection has a significant effect on the number of fruit bodies (P < 0.05). Only the soil moisture has a significant positive influence on the species richness of boletes (P > 0.05). Conclusions: When the soil moisture decreases by four units, the number of fruit bodies of ectomycorrhizal fungi is significantly reduced by one unit. Therefore, above 0.25 m3 / m3 and below 0.05 m3 / m3 there is a decrease in the number of fruit bodies.

scholarly journals Do syntopic host species harbour similar symbiotic communities? The case ofChaetopterusspp. (Annelida: Chaetopteridae)

PeerJ ◽  
2017 ◽  
Vol 5 ◽  
pp. e2930 ◽  
Author(s):  
Temir A. Britayev ◽  
Elena Mekhova ◽  
Yury Deart ◽  
Daniel Martin
Keyword(s):  
Species Richness ◽  
Community Structure ◽  
Host Species ◽  
Interspecific Interactions ◽  
Single Species ◽  
Intraspecific Interactions ◽  
Mean Intensity ◽  
Species Dominance ◽  
High Species Richness ◽  
Symbiotic Community

To assess whether closely related host species harbour similar symbiotic communities, we studied two polychaetes,Chaetopterussp. (n = 11) andChaetopteruscf.appendiculatus(n = 83) living in soft sediments of Nhatrang Bay (South China Sea, Vietnam). The former harboured the porcellanid crabsPolyonyxcf.heokandPolyonyxsp., the pinnotherid crabTetriassp. and the tergipedid nudibranchPhestillasp. The latter harboured the polynoid polychaeteOphthalmonoe pettiboneae, the carapid fishOnuxodon fowleriand the porcellanid crabEulenaios cometes, all of which, exceptO. fowleri, seemed to be specialized symbionts. The species richness and mean intensity of the symbionts were higher inChaetopterussp. than inC.cf.appendiculatus(1.8 and 1.02 species and 3.0 and 1.05 individuals per host respectively). We suggest that the lower density ofChaetopterussp. may explain the higher number of associated symbionts observed, as well as the 100% prevalence (69.5% inC.cf.appenciculatus). MostChaetopterussp. harboured two symbiotic species, which was extremely rare inC.cf.appendiculatus, suggesting lower interspecific interactions in the former. The crab and nudibranch symbionts ofChaetopterussp. often shared a host and lived in pairs, thus partitioning resources. This led to the species coexisting in the tubes ofChaetopterussp., establishing a tightly packed community, indicating high species richness and mean intensity, together with a low species dominance. In contrast, the aggressive, strictly territorial species associated withC.cf.appendiculatusestablished a symbiotic community strongly dominated by single species and, thus, low species richness and mean intensity. Therefore, we suggest that interspecific interactions are determining species richness, intensity and dominance, while intraspecific interactions are influencing only intensity and abundance. It is possible that species composition may have influenced the differences in community structure observed. We hypothesize that both host species could originally be allopatric. The evolutionary specialization of the symbiotic communities would occur in separated geographical areas, while the posterior disappearance of the existing geographical barriers would lead to the overlapped distribution.

scholarly journals Genotype-Species Interactions in Neighbourhoods of Forest Tree Communities

2007 ◽  
Vol 56 (1-6) ◽  
pp. 101-110 ◽  
Author(s):  
Chr. Wehenkel ◽  
F. Bergmann ◽  
H.-R. Gregorius
Keyword(s):  
Species Interactions ◽  
Species Coexistence ◽  
Biotic Interactions ◽  
Forest Tree ◽  
Target Species ◽  
Species Identity ◽  
Enzymatic Function ◽  
Genotype Frequencies ◽  
Tree Communities ◽  
Large Survey

Abstract Studies on plant communities of various annual species suggest that there are particular biotic interactions among individuals from different species which could be the basis for long-term species coexistence. In the course of a large survey on species-genetic diversity relationships in several forest tree communities, it was found that statistically significant differences exist among isozyme genotype frequencies of conspecific tree groups, which differ only by species identity of their neighbours. Based on a specific measure, the association of the neighbouring species with the genotypes of the target species or that of the genotypes with the neighbouring species was quantified. Since only AAT and HEK of the five analysed enzyme systems differed in their genotype frequencies among several tree groups of the same target species, a potential involvement of their enzymatic function in the observed differences was discussed. The results of this study demonstrate a fine-scale genetic differentiation within single tree species of forest communities, which may be the result of biotic interactions between the genetic structure of a species and the species composition of its community. This observation also suggests the importance of intraspecific genetic variation for interspecific adaptation.

scholarly journals Impact of Non-Timber Forest Product Use on the Tree Community in North-Western Vietnam

Forests ◽  
2018 ◽  
Vol 9 (7) ◽  
pp. 431 ◽  
Author(s):  
Thi Dao ◽  
Dirk Hölscher
Keyword(s):  
Tree Species ◽  
Logistic Model ◽  
Forest Products ◽  
Buffer Zone ◽  
Forest Types ◽  
Tree Community ◽  
Tree Communities ◽  
Non Timber Forest Products ◽  
Forest Use ◽  
North Western

Trees providing non-timber forest products (NTFPs) are valuable forest resources, and their management can support conservation objectives. We analyzed the abundance of tree species providing NTFPs, recognized by local H’mong people, in both the strictly protected core zone and the low-intensity forest use buffer zone in north-western Vietnam. We identified 249 tree species, of which 48% were classified as NTFP species. The abundance of 35% of the NTFP tree species was significantly correlated with footpaths, indicating an influence of human activity. A multiple logistic regression model indicates that using NTFP trees for food, medicine, and root harvesting, increases the probability of an NTFP tree absence in the buffer zone. In contrast, the high density of species, and collections of fruit, leaf, and resin decrease the probability of an NTFP tree absence in the buffer zone. Further assessment with a logistic model indicated that NTFP use has lower impacts on the tree community than timber use. We think that the parameterized models will enable comparisons of different situations and forest types and be particularly helpful in evaluating potential changes in tree communities over time.

Habitat use, interspecific competition and phylogenetic history shape the evolution of claw and toepad morphology in Lesser Antillean anoles

2020 ◽  
Vol 129 (3) ◽  
pp. 630-643 ◽  
Author(s):  
Michael L Yuan ◽  
Catherine Jung ◽  
Marvalee H Wake ◽  
Ian J Wang
Keyword(s):  
Interspecific Competition ◽  
Functional Traits ◽  
Functional Morphology ◽  
Biotic Interactions ◽  
Single Species ◽  
Morphometric Data ◽  
Opposite Pattern ◽  
Geometric Morphometric ◽  
Vegetation Use ◽  
Selective Forces

Abstract Ecologically functional traits are the product of several, at times opposing, selective forces. Thus, ecomorphological patterns can be disrupted locally by biotic interactions, such as competition, and may not be consistent across lineages. Here, we studied the evolution of claws and toepads in relationship to macrohabitat (vegetation), use of structural microhabitat (perch height) and congeneric competition for two distantly related Lesser Antillean anole clades: the Anolis bimaculatus and Anolis roquet series. We collected univariate and geometric morphometric data from 254 individuals across 22 species to test the hypotheses that functional morphology should covary with both vegetation and perch height and that the presence of a competitor may disrupt such covariation. Our data showed predictable associations between morphology and macrohabitat on single-species islands but not when a congeneric competitor was present. The outcomes of competition differed between series, however. In the A. bimaculatus series, species with a sympatric congener diverged in claw and toepad traits consistent with functional predictions, whereas A. roquet series anoles showed either no association between habitat and morphology or the opposite pattern. Our results demonstrated that ecomorphological patterns across macrohabitats can be disrupted by competition-driven microhabitat partitioning and that specific morphological responses to similar ecological pressures can vary between lineages.

scholarly journals Plant colonization, succession and ecosystem development on Surtsey with reference to neighbouring islands

2014 ◽  
Vol 11 (19) ◽  
pp. 5521-5537 ◽  
Author(s):  
B. Magnússon ◽  
S. H. Magnússon ◽  
E. Ólafsson ◽  
B. D. Sigurdsson
Keyword(s):  
Species Richness ◽  
Plant Biomass ◽  
Vascular Plant ◽  
Plant Cover ◽  
Soil Formation ◽  
Plant Succession ◽  
Permanent Plots ◽  
Plant Colonization ◽  
Nutrient Input ◽  
Species Richness And Diversity

Abstract. Plant colonization and succession on the volcanic island of Surtsey, formed in 1963, have been closely followed. In 2013, a total of 69 vascular plant species had been discovered on the island; of these, 59 were present and 39 had established viable populations. Surtsey had more than twice the species of any of the comparable neighbouring islands, and all of their common species had established on Surtsey. The first colonizers were dispersed by sea, but, after 1985, bird dispersal became the principal pathway with the formation of a seagull colony on the island and consequent site amelioration. This allowed wind-dispersed species to establish after 1990. Since 2007, there has been a net loss of species on the island. A study of plant succession, soil formation and invertebrate communities in permanent plots on Surtsey and on two older neighbouring islands (plants and soil) has revealed that seabirds, through their transfer of nutrients from sea to land, are major drivers of development of these ecosystems. In the area impacted by seagulls, dense grassland swards have developed and plant cover, species richness, diversity, plant biomass and soil carbon become significantly higher than in low-impact areas, which remained relatively barren. A similar difference was found for the invertebrate fauna. After 2000, the vegetation of the oldest part of the seagull colony became increasingly dominated by long-lived, rhizomatous grasses (Festuca, Poa, Leymus) with a decline in species richness and diversity. Old grasslands of the neighbouring islands Elliđaey (puffin colony, high nutrient input) and Heimaey (no seabirds, low nutrient input) contrasted sharply. The puffin grassland of Elliđaey was very dense and species-poor. It was dominated by Festuca and Poa, and very similar to the seagull grassland developing on Surtsey. The Heimaey grassland was significantly higher in species richness and diversity, and had a more even cover of dominants (Festuca/Agrostis/Ranunculus). We forecast that, with continued erosion of Surtsey, loss of habitats and increasing impact from seabirds a lush, species-poor grassland will develop and persist, as on the old neighbouring islands.

scholarly journals Predicting biodiversity richness in rapidly changing landscapes: climate, low human pressure or protection as salvation?

2020 ◽  
Vol 29 (14) ◽  
pp. 4035-4057
Author(s):  
David W. Macdonald ◽  
Luca Chiaverini ◽  
Helen M. Bothwell ◽  
Żaneta Kaszta ◽  
Eric Ash ◽  
...  
Keyword(s):  
Species Richness ◽  
Gap Analysis ◽  
Current System ◽  
Species Conservation ◽  
Biodiversity Loss ◽  
Single Species ◽  
Central China ◽  
Area Network ◽  
Biodiversity Hotspots ◽  
South Central

Abstract Rates of biodiversity loss in Southeast Asia are among the highest in the world, and the Indo-Burma and South-Central China Biodiversity Hotspots rank among the world’s most threatened. Developing robust multi-species conservation models is critical for stemming biodiversity loss both here and globally. We used a large and geographically extensive remote-camera survey and multi-scale, multivariate optimization species distribution modelling to investigate the factors driving biodiversity across these two adjoining biodiversity hotspots. Four major findings emerged from the work. (i) We identified clear spatial patterns of species richness, with two main biodiverse centres in the Thai-Malay Peninsula and in the mountainous region of Southwest China. (ii) Carnivores in particular, and large ungulates to a lesser degree, were the strongest indicators of species richness. (iii) Climate had the largest effect on biodiversity, followed by protected status and human footprint. (iv) Gap analysis between the biodiversity model and the current system of protected areas revealed that the majority of areas supporting the highest predicted biodiversity are not protected. Our results highlighted several key locations that should be prioritized for expanding the protected area network to maximize conservation effectiveness. We demonstrated the importance of switching from single-species to multi-species approaches to highlight areas of high priority for biodiversity conservation. In addition, since these areas mostly occur over multiple countries, we also advocate for a paradigmatic focus on transboundary conservation planning.

Do biotic interactions shape both sides of the humped-back model of species richness in plant communities?

2006 ◽  
Vol 9 (7) ◽  
pp. 767-773 ◽  
Author(s):  
Richard Michalet ◽  
Robin W. Brooker ◽  
Lohengrin A. Cavieres ◽  
Zaal Kikvidze ◽  
Christopher J. Lortie ◽  
...  
Keyword(s):  
Species Richness ◽  
Plant Communities ◽  
Biotic Interactions

scholarly journals Changes in plant diversity in a water-limited and isolated high-mountain range (Sierra Nevada, Spain)

Alpine Botany ◽  
2021 ◽  
Author(s):  
Andrea Lamprecht ◽  
Harald Pauli ◽  
Maria Rosa Fernández Calzado ◽  
Juan Lorite ◽  
Joaquín Molero Mesa ◽  
...  
Keyword(s):  
Species Richness ◽  
Snow Cover ◽  
Sierra Nevada ◽  
Plant Diversity ◽  
Endemic Species ◽  
Vascular Plant ◽  
Climate Change Impacts ◽  
Permanent Plots ◽  
High Mountain ◽  
Mountain Range

AbstractClimate change impacts are of a particular concern in small mountain ranges, where cold-adapted plant species have their optimum zone in the upper bioclimatic belts. This is commonly the case in Mediterranean mountains, which often harbour high numbers of endemic species, enhancing the risk of biodiversity losses. This study deals with shifts in vascular plant diversity in the upper zones of the Sierra Nevada, Spain, in relation with climatic parameters during the past two decades. We used vegetation data from permanent plots of three surveys of two GLORIA study regions, spanning a period of 18 years (2001–2019); ERA5 temperature and precipitation data; and snow cover durations, derived from on-site soil temperature data. Relationships between diversity patterns and climate factors were analysed using GLMMs. Species richness showed a decline between 2001 and 2008, and increased thereafter. Species cover increased slightly but significantly, although not for endemic species. While endemics underwent cover losses proportional to non-endemics, more widespread shrub species increased. Precipitation tended to increase during the last decade, after a downward trend since 1960. Precipitation was positively related to species richness, colonisation events, and cover, and negatively to disappearance events. Longer snow cover duration and rising temperatures were also related to increasing species numbers, but not to cover changes. The rapid biotic responses of Mediterranean alpine plants indicate a tight synchronisation with climate fluctuations, especially with water availability. Thus, it rather confirms concerns about biodiversity losses, if projections of increasing temperature in combination with decreasing precipitation hold true.

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