scholarly journals Multi-scale phenological niches in diverse Amazonian plant communities

2021 ◽  
Author(s):  
Damie Pak ◽  
Varun Swamy ◽  
Patricia Alvarez-Loayza ◽  
Fernando Cornejo ◽  
Simon A. Queenborough ◽  
...  
Keyword(s):  
Plant Communities ◽  
Species Coexistence ◽  
Niche Partitioning ◽  
Fruit Production ◽  
Reproductive Phenology ◽  
Positive Interactions ◽  
Temporal Scales ◽  
Tropical Plant ◽  
Wide Range ◽  
Environmental Responses

Phenology has long been hypothesized as an avenue for niche partitioning or interspecific facilitation, both promoting species coexistence. Tropical plant communities exhibit striking diversity in reproductive phenology, including seasonal patterns of fruit production. Here we study whether this phenological diversity is non-random, what are the temporal scales of phenological patterns, and ecological factors that drive reproductive phenology. We applied multivariate wavelet analyses to test for phenological synchrony versus compensatory dynamics (i.e. anti-synchronous patterns where one species' decline is compensated by the rise of another) among species and across temporal scales. We used data from long-term seed rain monitoring of hyperdiverse plant communities in the western Amazon. We found significant synchronous whole-community phenology at a wide range of time scales, consistent with shared environmental responses or positive interactions among species. We also observed both compensatory and synchronous phenology within groups of species likely to share traits (confamilials) and seed dispersal mechanisms. Wind-dispersed species exhibited significant synchrony at ~6 mo scales, suggesting these species share phenological niches to match seasonality of wind. Our results indicate that community phenology is shaped by shared environmental responses but that the diversity of tropical plant phenology partly results from temporal niche partitioning. The scale-specificity and time-localized nature of community phenology patterns highlights the importance of multiple and shifting drivers of phenology.

scholarly journals Neighborhood matters: high phylogenetic diversity of experimental plant assemblages improves community performance

2021 ◽  
Author(s):  
Rocío Chaves ◽  
Pablo Ferrandis ◽  
Adrián Escudero ◽  
Arantzazu L. Luzuriaga
Keyword(s):  
Plant Communities ◽  
Phylogenetic Diversity ◽  
Species Coexistence ◽  
Spatial Scales ◽  
Positive Interactions ◽  
Experimental Plant ◽  
Large Species ◽  
Plant Survival ◽  
Niche Complementarity ◽  
Plant Assemblages

Abstract Background and AimsAlthough the role played by phylogeny in the assembly of plant communities remains as a priority to complete the theory of species coexistence, experimental evidence is lacking. It is still unclear to what extent phylogenetic diversity is a driver or a consequence of species assembly processes. We experimentally explored how phylogenetic diversity can drive the community level responses to drought conditions in annual plant communities. To this end, we manipulated the phylogenetic diversity of the species assemblages and the water availability in a common garden experiment with two treatments: average natural rainfall and drought.MethodsWe recorded plant survival and the numbers of flowering and fruiting plants per species in each assemblage. High phylogenetic diversity favored species coexistence over time with higher plant survival and more flowering and fruiting plants, especially under severe drought.Key Results. Our results demonstrate the existence of niche complementarity and the convergence of water economy strategies as major mechanisms for promoting species coexistence in plant assemblages in semiarid Mediterranean habitats.ConclusionsOur findings point to high phylogenetic diversity among neighboring plants as a plausible feature underpinning the recent “united we stand” framework, which states that diffuse positive interactions may promote mechanisms for the persistence of rare species in the community. We suggest that the large species number in the regional species pool may be the consequence of assembly processes occurring at small spatial scales, because the success of each species in terms of surviving and producing offspring was greater when the phylogenetic diversity was higher. Our study is a step forward to understand how phylogenetic relatedness is connected to the mechanisms determining the maintenance of biodiversity.

scholarly journals Forbidden links, trait matching and modularity in plant-hummingbird networks: Are specialized modules characterized by higher phenotypic floral integration?

PeerJ ◽  
2021 ◽  
Vol 9 ◽  
pp. e10974
Author(s):  
Jaume Izquierdo-Palma ◽  
Maria del Coro Arizmendi ◽  
Carlos Lara ◽  
Juan Francisco Ornelas
Keyword(s):  
Species Coexistence ◽  
Niche Partitioning ◽  
Modular Organization ◽  
Minor Role ◽  
Biological Processes ◽  
Generalist Species ◽  
Tropical Plant ◽  
Plant Assemblage ◽  
Morphological Specialization ◽  
Understory Plant

Background Plant-pollinator mutualistic networks show non-random structural properties that promote species coexistence. However, these networks show high variability in the interacting species and their connections. Mismatch between plant and pollinator attributes can prevent interactions, while trait matching can enable exclusive access, promoting pollinators’ niche partitioning and, ultimately, modularity. Thus, plants belonging to specialized modules should integrate their floral traits to optimize the pollination function. Herein, we aimed to analyze the biological processes involved in the structuring of plant-hummingbird networks by linking network morphological constraints, specialization, modularity and phenotypic floral integration. Methods We investigated the understory plant-hummingbird network of two adjacent habitats in the Lacandona rainforest of Mexico, one characterized by lowland rainforest and the other by savanna-like vegetation. We performed monthly censuses to record plant-hummingbird interactions for 2 years (2018–2020). We also took hummingbird bill measurements and floral and nectar measurements. We summarized the interactions in a bipartite matrix and estimated three network descriptors: connectance, complementary specialization (H2’), and nestedness. We also analyzed the modularity and average phenotypic floral integration index of each module. Results Both habitats showed strong differences in the plant assemblage and network dynamics but were interconnected by the same four hummingbird species, two Hermits and two Emeralds, forming a single network of interaction. The whole network showed low levels of connectance (0.35) and high specialization (H2’ = 0.87). Flower morphologies ranged from generalized to specialized, but trait matching was an important network structurer. Modularity was associated with morphological specialization. The Hermits Phaethornis longirostris and P. striigularis each formed a module by themselves, and a third module was formed by the less-specialized Emeralds: Chlorestes candida and Amazilia tzacatl. The floral integration values were higher in specialized modules but not significantly higher than that formed by generalist species. Conclusions Our findings suggest that biological processes derived from both trait matching and “forbidden” links, or nonmatched morphological attributes, might be important network drivers in tropical plant-hummingbird systems while morphological specialization plays a minor role in the phenotypic floral integration. The broad variety of corolla and bill shapes promoted niche partitioning, resulting in the modular organization of the assemblage according to morphological specialization. However, more research adding larger datasets of both the number of modules and pollination networks for a wider region is needed to conclude whether phenotypic floral integration increases with morphological specialization in plant-hummingbird systems.

scholarly journals Equine strongyle communities are constrained by horse sex and species dipersal-fecundity trade-off

2017 ◽  
Author(s):  
Sallé Guillaume ◽  
Kornaś Sławomir ◽  
Basiaga Marta
Keyword(s):  
Species Coexistence ◽  
Control Strategies ◽  
Niche Partitioning ◽  
Community Diversity ◽  
Dispersal Ability ◽  
Positive Interactions ◽  
Species Dispersal ◽  
Trade Off ◽  
Trade Offs ◽  
Differential Control

AbstractEquine strongyles are a major health issue. Large strongyles can cause death of horses while cyathostomins (small strongyles) have shown increased resistance to anthelmintics worldwide. Description of strongyle communities have accumulated but little is known about the diversity of these communities and underpinning environmental factors.This study analysed the diversity of strongyle communities in 48 horses from Poland. Strongyle species fell into two groups, contrasted by their prevalence and relative abundance. Seven horses were necessary to sample at least 90% of strongyle community diversity, providing a minimal cut-off to implement sampling trial in the field. Strongyle communities entertained a network of mostly positive interactions and species co-occurrence was found more often than expected by chance. In addition, species fecundity and prevalence were negatively correlated r=-0.78), suggesting functional trade-offs between species dispersal abilities and fecundity. This functional trade-off may underpin species coexistence. Horse sex was also a significant constraint shaping strongyle communities. Indeed, mares generally displayed more similar strongyle communities than stallions (p=0.004) and Cylicostephanus calicatus was more abundant in stallions suggesting sex-specific interactions (p=0.02). While niche partitioning is likely to explain some of the positive interactions between equine strongyle species, coexistence may also result from a functional trade-off between dispersal ability and fecundity. There is significant evidence that horse sex drives strongylid community structure, which may require differential control strategies between mares and stallions.

scholarly journals Impacts of Land-Use Changes on Vegetation and Ecosystem Functioning: Old-Field Secondary Succession

Plants ◽  
2021 ◽  
Vol 10 (5) ◽  
pp. 990
Author(s):  
Javier Pérez-Hernández ◽  
Rosario G. Gavilán
Keyword(s):  
Plant Communities ◽  
Ecosystem Functioning ◽  
Secondary Succession ◽  
Species Coexistence ◽  
Human Impacts ◽  
Soil Seed Bank ◽  
Land Use Changes ◽  
Dispersal Limitation ◽  
Point Of View ◽  
Old Field

The study of ecological succession to determine how plant communities re-assemble after a natural or anthropogenic disturbance has always been an important topic in ecology. The understanding of these processes forms part of the new theories of community assembly and species coexistence, and is attracting attention in a context of expanding human impacts. Specifically, new successional studies provide answers to different mechanisms of community assemblage, and aim to define the importance of deterministic or stochastic processes in the succession dynamic. Biotic limits, which depend directly on biodiversity (i.e., species competition), and abiotic filtering, which depends on the environment, become particularly important when they are exceeded, making the succession process more complicated to reach the previous disturbance stage. Plant functional traits (PFTs) are used in secondary succession studies to establish differences between abandonment stages or to compare types of vegetation or flora, and are more closely related to the functioning of plant communities. Dispersal limitation is a PFT considered an important process from a stochastic point of view because it is related to the establishing of plants. Related to it the soil seed bank plays an important role in secondary succession because it is essential for ecosystem functioning. Soil compounds and microbial community are important variables to take into account when studying any succession stage. Chronosequence is the best way to study the whole process at different time scales. Finally, our objective in this review is to show how past studies and new insights are being incorporated into the basis of classic succession. To further explore this subject we have chosen old-field recovery as an example of how a number of different plant communities, including annual and perennial grasslands and shrublands, play an important role in secondary succession.

scholarly journals Effects of environmental conditions associated to the cardinal orientation on the reproductive phenology of the cerrado savanna tree Xylopia aromatica (Annonaceae)

2011 ◽  
Vol 83 (3) ◽  
pp. 1007-1020 ◽  
Author(s):  
Maria Gabriela G. Camargo ◽  
Regina M. Souza ◽  
Paula Reys ◽  
Leonor P.C. Morellato
Keyword(s):  
Edge Effects ◽  
Environmental Conditions ◽  
Fruit Production ◽  
Sensu Stricto ◽  
Southeastern Brazil ◽  
Reproductive Phenology ◽  
Canopy Openness ◽  
Cerrado Savanna ◽  
Cardinal Direction ◽  
Floral Visitation

The Brazilian cerrado has undergone an intense process of fragmentation, which leads to an increase in the number of remnants exposed to edge effects and associated changes on environmental conditions that may affect the phenology of plants. This study aimed to verify whether the reproductive phenology of Xylopia aromatica (Lam.) Mart. (Annonaceae) differs under different light conditions in a cerrado sensu stricto (a woody savanna) of southeastern Brazil. We compared the reproductive phenology of X. aromatica trees distributed on east and south cardinal faces of the cerrado during monthly observations, from January 2005 to December 2008. The east face had a higher light incidence, higher temperatures and canopy openness in relation to south face. X. aromatica showed seasonal reproduction at both faces of the cerrado, but the percentage of individuals, the synchrony and duration of phenophases were higher at the east face. The study demonstrated the influence of the environmental conditions associated to the cardinal orientation of the cerrado faces on the phenological pattern of X. aromatica. Similar responses may be observed for other species, ultimately affecting patterns of floral visitation and fruit production, which reinforces the importance of considering the cardinal direction in studies of edge effects and fragmentation.

scholarly journals Agricultural crops in the diet of bearded capuchin monkeys, Cebus libidinosus Spix (Primates: Cebidae), in forest fragments in southeast Brazil

2008 ◽  
Vol 25 (1) ◽  
pp. 32-39 ◽  
Author(s):  
Carlos Henrique de Freitas ◽  
Eleonore Z. F. Setz ◽  
Alba R. B. Araújo ◽  
Nivar Gobbi
Keyword(s):  
Fruit Production ◽  
Dry Season ◽  
Southeastern Brazil ◽  
Capuchin Monkeys ◽  
Home Ranges ◽  
Forest Fragments ◽  
Wet Season ◽  
Plant Matter ◽  
Wide Range ◽  
Cebus Libidinosus

Capuchin monkeys occupy a wide range of habitats where they feed on fruits, arthropods, and vertebrates. Their large home ranges (80-900 ha) suggest that living in forest fragments may challenge their adaptability. We identified and quantified the main food items of Cebus libidinosus Spix, 1823 in forests fragments (100 ha) in southeastern Brazil. We recorded the feeding activities of two groups using scan sampling over a 13-month period. The diet was composed of fruits, crops, animal prey, seeds, plant matter and undetermined. Fruit was eaten more in the wet season than in the dry season, and maize and sugar cane consumption peaked in the early dry season. The proportion of fruit in the diet was positively correlated with fruiting intensity of zoochorous trees. The plant diet included 54 species, with maize, Rhamnidium elaeocarpus, Acrocomia aculeata, Guazuma ulmifolia and Cariniana, being most important. Although dietary composition and diversity were similar to capuchins in larger forest fragments, feeding on crops attained higher percentages at times when zoochorous fruit production was low in fragments.

Willows in the environment

1992 ◽  
Vol 98 ◽  
pp. 215-224 ◽  
Author(s):  
Alastair H. C. Sommerville
Keyword(s):  
Plant Communities ◽  
Ecological Role ◽  
Large Numbers ◽  
Wide Range

SynopsisThe ecological role of native willows is described in terms of the diverse structure of the species involved, the wide range of plant communities they form and the large numbers of invertebrates associated with them. The conservation importance of the genusSalixis discussed along with comments on the necessary management to retain willow habitats.

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