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1.
Bull Math Biol ; 86(8): 103, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38980452

RESUMO

Phylogenetic diversity indices are commonly used to rank the elements in a collection of species or populations for conservation purposes. The derivation of these indices is typically based on some quantitative description of the evolutionary history of the species in question, which is often given in terms of a phylogenetic tree. Both rooted and unrooted phylogenetic trees can be employed, and there are close connections between the indices that are derived in these two different ways. In this paper, we introduce more general phylogenetic diversity indices that can be derived from collections of subsets (clusters) and collections of bipartitions (splits) of the given set of species. Such indices could be useful, for example, in case there is some uncertainty in the topology of the tree being used to derive a phylogenetic diversity index. As well as characterizing some of the indices that we introduce in terms of their special properties, we provide a link between cluster-based and split-based phylogenetic diversity indices that uses a discrete analogue of the classical link between affine and projective geometry. This provides a unified framework for many of the various phylogenetic diversity indices used in the literature based on rooted and unrooted phylogenetic trees, generalizations and new proofs for previous results concerning tree-based indices, and a way to define some new phylogenetic diversity indices that naturally arise as affine or projective variants of each other or as generalizations of tree-based indices.


Assuntos
Biodiversidade , Filogenia , Modelos Genéticos , Conceitos Matemáticos , Evolução Biológica , Animais
2.
Environ Monit Assess ; 196(8): 691, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38960930

RESUMO

Urban forests face multiple human-mediated pressures leading to compromised ecosystem structure and functioning. Therefore, understanding ecosystem structure in response to ongoing pressures is crucial for sustaining ecological integrity and human well-being. We aim to assess the disturbance and its effects on the vegetation structure of urban forests in Chandigarh using a combination of remote sensing techniques and vegetation surveys. The disturbance was evaluated as a change in NDVI (Normalised Difference Vegetation Index) from 2001 to 2021 by applying the BFAST (Breaks For Additive Season and Trend) algorithm to the MODIS satellite imagery data. A vegetation survey was conducted to compare the species composition, taxonomic and phylogenetic diversity as measures of forest vegetational structure. While signals of disturbance were evident, the changes in vegetation structure were not well established from our study. Further, this analysis indicated no significant differences in vegetation composition due to disturbance (F1,12 = 0.91, p = 0.575). However, the phylogenetic diversity was substantially lower for disturbed plots than undisturbed plots, though the taxonomic diversity was similar among the disturbed and undisturbed plots. Our results confirmed that disturbance effects are more prominent on the phylogenetic than taxonomic diversity. These findings can be considered early signals of disturbance and its impact on the vegetation structure of urban forests and contribute to the knowledge base on urban ecosystems. Our study has implications for facilitating evidence-based decision-making and the development of sustainable management strategies for urban forest ecosystems.


Assuntos
Biodiversidade , Monitoramento Ambiental , Florestas , Monitoramento Ambiental/métodos , Índia , Cidades , Ecossistema , Imagens de Satélites , Tecnologia de Sensoriamento Remoto , Conservação dos Recursos Naturais , Árvores , Filogenia
3.
Ecol Appl ; : e3010, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38978282

RESUMO

Since 2014, highly pathogenic avian influenza (HPAI) H5 viruses of clade 2.3.4.4 have been dominating the outbreaks across Europe, causing massive deaths among poultry and wild birds. However, the factors shaping these broad-scale outbreak patterns, especially those related to waterbird community composition, remain unclear. In particular, we do not know whether these risk factors differ from those of other H5 clades. Addressing this knowledge gap is important for predicting and preventing future HPAI outbreaks. Using extensive waterbird survey datasets from about 6883 sites, we here explored the effect of waterbird community composition on HPAI H5Nx (clade 2.3.4.4) spatial patterns in the 2016/2017 and 2020/2021 epidemics in Europe, and compared it with the 2005/2006 HPAI H5N1 (clade 2.2) epidemic. We showed that HPAI H5 occurrences in wild birds in the three epidemics were strongly associated with very similar waterbird community attributes, which suggested that, in nature, similar interspecific transmission processes operate between the HPAI H5 subtypes or clades. Importantly, community phylogenetic diversity consistently showed a negative association with H5 occurrence in all three epidemics, suggesting a dilution effect of phylogenetic diversity. In contrast, waterbird community variables showed much weaker associations with HPAI H5Nx occurrence in poultry. Our results demonstrate that models based on previous epidemics can predict future HPAI H5 patterns in wild birds, implying that it is important to include waterbird community factors in future HPAI studies to predict outbreaks and improve surveillance activities.

4.
Ecol Lett ; 27(6): e14465, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38934685

RESUMO

A branch of island biogeography has emerged to explain alien species diversity in the light of the biogeographic and anthropogenic context, yet overlooking the functional and phylogenetic facets. Evaluating alien and native birds of 407 oceanic islands worldwide, we built structural equation models to assess the direct and indirect influence of biotic, geographic, and anthropogenic contexts on alien functional diversity (FD) and phylogenetic diversity (PD). We found that alien taxonomic richness was the main predictor of both diversities. Anthropogenic factors, including colonization pressure, associated with classic biogeographical variables also strongly influenced alien FD and PD. Specifically, habitat modification and human connectivity markedly drove alien FD, especially when controlled by taxonomic richness, whereas the human population size, gross domestic product, and native PD were crucial at explaining alien PD. Our findings suggest that humans not only shape taxonomic richness but also other facets of alien diversity in a complex way.


Assuntos
Biodiversidade , Aves , Espécies Introduzidas , Ilhas , Filogenia , Animais , Aves/fisiologia , Filogeografia , Humanos , Ecossistema , Efeitos Antropogênicos
5.
Evol Appl ; 17(6): e13728, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38884021

RESUMO

Given the multitude of challenges Earth is facing, sustainability science is of key importance to our continued existence. Evolution is the fundamental biological process underlying the origin of all biodiversity. This phylogenetic diversity fosters the resilience of ecosystems to environmental change, and provides numerous resources to society, and options for the future. Genetic diversity within species is also key to the ability of populations to evolve and adapt to environmental change. Yet, the value of evolutionary processes and the consequences of their impairment have not generally been considered in sustainability research. We argue that biological evolution is important for sustainability and that the concepts, theory, data, and methodological approaches used in evolutionary biology can, in crucial ways, contribute to achieving the UN Sustainable Development Goals (SDGs). We discuss how evolutionary principles are relevant to understanding, maintaining, and improving Nature Contributions to People (NCP) and how they contribute to the SDGs. We highlight specific applications of evolution, evolutionary theory, and evolutionary biology's diverse toolbox, grouped into four major routes through which evolution and evolutionary insights can impact sustainability. We argue that information on both within-species evolutionary potential and among-species phylogenetic diversity is necessary to predict population, community, and ecosystem responses to global change and to make informed decisions on sustainable production, health, and well-being. We provide examples of how evolutionary insights and the tools developed by evolutionary biology can not only inspire and enhance progress on the trajectory to sustainability, but also highlight some obstacles that hitherto seem to have impeded an efficient uptake of evolutionary insights in sustainability research and actions to sustain SDGs. We call for enhanced collaboration between sustainability science and evolutionary biology to understand how integrating these disciplines can help achieve the sustainable future envisioned by the UN SDGs.

6.
Plants (Basel) ; 13(11)2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38891345

RESUMO

The investigation of taxonomic diversity within island plant communities stands as a central focus in the field of island biogeography. Phylogenetic diversity is crucial for unraveling the evolutionary history, ecological functions, and species combinations within island plant communities. Island effects (area and isolation effect) may shape species distribution patterns, habitat heterogeneity affects habitat diversity, and anthropogenic disturbances can lead to species extinction and habitat destruction, thus impacting both species diversity and phylogenetic diversity. To investigate how taxonomic and phylogenetic diversity in island natural plant communities respond to island effects, habitat heterogeneity, and anthropogenic disturbances, we took the main island of Haitan (a land-bridge island) and nine surrounding islands (oceanic islands) of varying sizes as the subjects of our study on the Pingtan islands. We aim to elucidate the influence of island effects, habitat heterogeneity, and anthropogenic disturbances on taxonomic and phylogenetic diversity. The results showed that, (1) Both the taxonomic and phylogenetic diversity of plants on the Pingtan islands followed the island area effect, indicating that as the island area increases, both taxonomic and phylogenetic diversity also increase. (2) Island effects and habitat heterogeneity were found to enhance taxonomic and phylogenetic diversity, whereas anthropogenic disturbances were associated with a decrease in both taxonomic and phylogenetic diversity. Furthermore, the synergistic influence of island effects, habitat heterogeneity, and anthropogenic disturbances collectively exerted a negative impact on both taxonomic and phylogenetic diversity. (3) The contribution of explanatory variables of anthropogenic disturbances for taxonomic and phylogenetic diversity was higher than that of island effects and habitat heterogeneity. Additionally, the contribution of the explanatory variables under the combined influence of island effects, habitat heterogeneity, and anthropogenic disturbances is higher than that of the individual variables for island effects and habitat heterogeneity. These findings suggest that anthropogenic disturbances emerged as the dominant factors influencing both taxonomic and phylogenetic diversity. These findings demonstrate the intricate interplay between island effects, habitat heterogeneity, and anthropogenic disturbances, highlighting their combined influence on both taxonomic and phylogenetic diversity on island.

7.
Appl Plant Sci ; 12(3): e11587, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38912125

RESUMO

Premise: Conservation policies typically focus on biodiversity hotspots. An alternative approach involves analyzing the evolutionary history of lineages in geographic areas along with their threat levels to guide conservation efforts. Mountains exhibit high levels of plant species richness and micro-endemism, and biogeographic studies commonly point to recent and rapid evolutionary radiations in these areas. Using a nearly endemic clade of legumes, our study evaluates conservation prioritization approaches in the campo rupestre, a Neotropical ecosystem associated with mountaintops that is located between two biodiversity hotspots. Methods: We compared the EDGE and EDGE2 metrics, which combine the evolutionary distinctiveness and the extinction risk of a species in a single value. These metrics are compared with traditional metrics used to assess conservation priority, such as phylogenetic diversity. Results: The EDGE values reported are lower than those of other studies using this metric, mostly due to the prevalence of threatened species with short phylogenetic branch lengths (low values of evolutionary distinctiveness). Certain areas of campo rupestre with relatively high phylogenetic diversity and EDGE values do not correspond to areas with high species richness, agreeing with previous studies on biodiversity hotspots. Discussion: Our study highlights the necessity of conservation of the campo rupestres as well as advantages and disadvantages of using EDGE, EDGE2, and phylogenetic diversity for appropriate selection of conservation areas with rapid evolutionary radiations. The selection of the metrics will depend primarily on the life history of the focus group and the data availability, as well as the conservation approach.

8.
Sci Total Environ ; 935: 173343, 2024 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-38777069

RESUMO

Niche convergence or conservatism have been proposed as essential mechanisms underlying elevational plant community assembly in tropical mountain ecosystems. Subtropical mountains, compared to tropical mountains, are likely to be shaped by a mixing of different geographic affinities of species and remain somehow unclear. Here, we used 31 0.1-ha permanent plots distributed in subtropical forests on the eastern and western aspects of the Gaoligong Mountains, southwest China between 1498 m and 3204 m a.sl. to evaluate how niche-based and biogeographic processes shape tree community assembly along elevational gradients. We analyzed the elevational patterns of taxonomic, phylogenetic and functional diversity, as well as of individual traits, and assessed the relative importance of environmental effects on these diversity measures. We then classified tree species as being either tropical affiliated or temperate affiliated and estimated their contribution to the composition of biogeographic affinities. Species richness decreased with elevation, and species composition showed apparent turnover across the aspects and elevations. Most traits exhibited convergent patterns across the entire elevational gradient. Phylogenetic and functional diversity showed opposing patterns, with phylogenetic diversity increasing and functional diversity decreasing with elevation. Soil nutrients, especially phosphorus and nitrogen, appeared to be the main abiotic variables driving the elevational diversity patterns. Communities at lower elevations were occupied by tropical genera, while highlands contained species of tropical and temperate biogeographic affinities. Moreover, the high phylogenetic diversity at high elevations were likely due to differences in evolutionary history between temperate and tropical species. Our results highlight the importance of niche convergence of tropical species and the legacy of biogeographic history on the composition and structure of subtropical mountain forests. Furthermore, limited soil phosphorus caused traits divergence and the partitioning for different forms of phosphorus may explain the high biodiversity found in phosphorus-limited subtropical forests.


Assuntos
Altitude , Biodiversidade , Florestas , Árvores , China , Filogenia , Ecossistema , Clima Tropical
9.
J Math Biol ; 89(1): 5, 2024 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-38761189

RESUMO

Phylogenetic diversity indices provide a formal way to apportion evolutionary history amongst living species. Understanding the properties of these measures is key to determining their applicability in conservation biology settings. In this work, we investigate some questions posed in a recent paper by Fischer et al. (Syst Biol 72(3):606-615, 2023). In that paper, it is shown that under certain extinction scenarios, the ranking of the surviving species by their Fair Proportion index scores may be the complete reverse of their ranking beforehand. Our main results here show that this behaviour extends to a large class of phylogenetic diversity indices, including the Equal-Splits index. We also provide a necessary condition for reversals of Fair Proportion rankings to occur on phylogenetic trees whose edge lengths obey the ultrametric constraint. Specific examples of rooted phylogenetic trees displaying these behaviours are given and the impact of our results on the use of phylogenetic diversity indices more generally is discussed.


Assuntos
Biodiversidade , Extinção Biológica , Filogenia , Animais , Conceitos Matemáticos , Conservação dos Recursos Naturais/estatística & dados numéricos , Evolução Biológica , Modelos Biológicos
10.
Sci Total Environ ; 935: 173379, 2024 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-38795992

RESUMO

Understanding how organisms are coping with major changes imposed by urban intensification is a complex task. In fact, our understanding of the impacts of urbanization on biodiversity is scarce in the global south compared to the north. In this study, we evaluated how bird communities are affected by impact of urban intensification in a tropical city. Thus, we assessed whether increased urban intensification 1) jeopardizes bird diversity (taking into account taxonomic-TD, phylogenetic-PD, and functional-FD dimensions), 2) drives changes in bird community composition and enables the detection of indicator species of such impact, and 3) leads to changes in bird functional traits linked to reproduction, resource acquisition, and survival. We found that urban intensification has a direct impact on the bird community, reducing all three types of diversity. Communities in areas of greater urban intensity are represented by fewer species, and these species are PD and FD less distinct. In addition, we detected at least ten species of areas of lower urban intensity that proved to be more sensitive to urban intensification. With regard to bird traits, we found no significant responses from reproductive, habitat use and feeding variables. Body weight and tail length were the only variables with significant results, with higher urbanization intensity areas selecting for species with lower weights and longer tails. Given the global biodiversity loss we are observing, this information can guide urban managers and planners in designing urban landscapes to maintain biodiversity in cities.


Assuntos
Biodiversidade , Aves , Cidades , Urbanização , Animais , Aves/fisiologia , Ecossistema , Clima Tropical , Monitoramento Ambiental
11.
Curr Zool ; 70(2): 204-213, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38726258

RESUMO

Understanding the mechanisms of community assembly is a key question in ecology. Metal pollution may result in significant changes in bird community structure and diversity, with implications for ecosystem processes and function. However, the relative importance of these processes in shaping the bird community at the polluted area is still not clear. Here, we explored bird species richness, functional, and phylogenetic diversity, and the assembly processes of community at the mine region of southwest China. Our results showed that the 3 dimensions of diversity at the mine area were lower than that at the reference sites. In the community assembly, the result was 0 < NRI/ NFRI < 1.96, which indicated deterministic processes (environmental filtering) might drive community clustering. The results of the neutral community model, and normalized stochasticity ratio, showed the dominant role of stochastic processes in shaping the bird community assembly. We further quantified the community-level habitat niche breadth (Bcom), and we found that there was no difference in Bcom-value between the mine area and reference sites. This indicates that the bird communities at the mine area and 3 reference sites were not subjected to extreme environmental selection (same or different resource allocation) to form a highly specialized niche. These findings provide insights into the distribution patterns and dominant ecological processes of bird communities under metal exposure, and extend the knowledge in community assembly mechanisms of bird communities living in the mine area.

12.
Ecol Evol ; 14(5): e11431, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38770121

RESUMO

Forest soils are a critical component of terrestrial ecosystems and host a large number of animal decomposer species. One diverse and abundant decomposer taxon is oribatid mites (Acari: Oribatida), whose species composition varies with forest type and tree species composition. We used functional traits that indicate different niche dimensions, to infer assembly processes of oribatid mite communities in monocultures and mixed forests of native and introduced tree species. We found that coexisting species differed more in the resource-related niche dimension, i.e., reproductive mode and trophic guild, than in the morphological dimension, e.g., body length and width, sclerotization and concealability. These results suggest that both filtering and partitioning processes structure oribatid mite communities. In native European beech forests, but not in non-native Douglas fir forests, oribatid mites were mainly structured by filtering processes acting via traits related both to environmental tolerance and to resources. Furthermore, oribatid mite trait diversity, but not phylogenetic diversity, differed significantly between monocultures and mixed forests, demonstrating that multidimensional diversity indices provide additional information on soil biodiversity. Overall, the study provides evidence that traits representing different niche dimensions need to be considered for understanding assembly processes in soil animal communities and thereby soil biodiversity.

13.
Ann Bot ; 2024 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-38795069

RESUMO

BACKGROUND AND AIMS: Latitudinal diversity gradients have been intimately linked to the tropical niche conservatism hypothesis, which posits that there has been a strong filter due to the challenges faced by ancestral tropical lineages to adapt to low temperatures and colonize extra-tropical regions. In liverworts, species richness is higher towards the tropics, but the centers of diversity of the basal lineages are distributed across extra-tropical regions, pointing to the colonization of tropical regions by phylogenetically clustered assemblages of species of temperate origin. Here, we test this hypothesis through analyses on the relationship between macroclimatic variation and phylogenetic diversity in Chinese liverworts. METHODS: Phylogenetic diversity metrics and their standardized effect sizes for liverworts in each of the 28 regional floras at the province level in China were related to latitude and six climate variables using regression analysis. We conducted variation partitioning analyses to determine the relative importance of each group of climatic variables. KEY RESULTS: We find that the number of species decreases with latitude, whereas phylogenetic diversity shows the reverse pattern, and that phylogenetic diversity is more strongly correlated with temperature-related variables, compared with precipitation-related variables. CONCLUSIONS: We interpret the opposite patterns observed in phylogenetic diversity and species richness in terms of a more recent origin of tropical diversity coupled with higher extinctions in temperate regions.

14.
J Environ Manage ; 359: 120995, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38692030

RESUMO

Globally, rapid climate and land-use changes in alpine environments are posing severe risks to their bountiful biodiversity and ecosystem services. Currently, nature-based solutions are fast-emerging as the preferred approach to address the challenges of environmental sustainability. In alpine environments, cushion plants owing to their unique architecture and adaptability offer a potential nature-based system to plan biodiversity conservation and habitat restoration strategies. Here, we employed an analytical framework to test whether and how the cushion plants facilitate the sustenance of alpine plant diversity in Kashmir Himalaya. We specifically aimed to answer: what are the effects of the cushion plants on the patterns of alpine species richness and phylogenetic diversity, and whether these effects vary across spatial scales (local versus landscape), cushion types, and changing elevation. We randomly selected pairs of cushion and neighbouring non-cushion plots (size 100 m2) across 34 different alpine sites in the study region. Within each plot, we randomly laid three 5 m2 quadrats for vegetation sampling, and sampled a total of 204 quadrats in 68 plots with seven cushion types along elevation ranging from 3100 to 3850 m. Our results revealed positive effects of the cushions by supporting a higher community species richness (SR) and phylogenetic diversity (PD). The effects were consistent both at the local (i.e., quadrat) and landscape (i.e., plot) scales, but varied significantly with the cushion type. Interestingly, SR and PD showed an increasing trend with increase in elevation in cushion communities, thereby supporting stress gradient hypothesis. Along the elevational gradient, the cushion communities showed phylogenetic overdispersion, but clustering by non-cushions. Overall, our study provides empirical evidence to reinforce the role of the cushions as conservation refugia for an imperilled alpine plant diversity in the Himalaya. Looking ahead, we highlight the far-reaching implications of our findings in guiding the nature-based environmental management of alpine ecosystems worldwide.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais , Ecossistema , Filogenia , Plantas
15.
Philos Trans R Soc Lond B Biol Sci ; 379(1902): 20230324, 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38583470

RESUMO

Human activities are causing taxonomic rearrangements across ecosystems that often result in the emergence of novel communities (assemblies with no historical representative). It is commonly assumed that these changes in the taxonomic makeup of ecosystems also inevitably lead to changes in other aspects of biodiversity, namely functional and phylogenetic diversity. However, this assumption is not always valid, as the changes in functional and phylogenetic composition resulting from taxonomic shifts depend on the level of redundancy in the evaluated community. Therefore, we need improved theoretical frameworks to predict when we can expect coordinated or decoupled responses among these three facets of biodiversity. To advance this understanding, we discuss the conceptual and methodological issues that complicate establishing a link between taxonomic rearrangements driven by human activities and the associated functional and phylogenetic changes. Here, we show that is crucial to consider the expected changes in functional and phylogenetic composition as communities are reshaped owing to human drivers of biodiversity loss to forecast the impacts of novel assemblages on ecosystem functions and the services they provide to humanity. This article is part of the theme issue 'Ecological novelty and planetary stewardship: biodiversity dynamics in a transforming biosphere'.


Assuntos
Biodiversidade , Ecossistema , Humanos , Filogenia , Osso e Ossos
16.
Biodivers Data J ; 12: e116135, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38434749

RESUMO

Background: The patterns of richness, diversity, and abundance of an odonate assemblage from San Buenaventura, Jalisco are presented here. A total of 1087 specimens from seven families, 35 genera and 66 species were obtained through monthly samplings of five days each during a period of one year. Libellulidae was the most diverse family (28 species), followed by Coenagrionidae (21), Gomphidae (7), Aeshnidae (6), Calopterygidae (2), Lestidae (1) and Platystictidae (1). Argia was the most speciose genus. The highest species richness and Shannon diversity were found during August and September, whereas the highest abundance was observed in June and the highest Simpson diversity was recorded in September - all of which were associated with the rainy season. The highest values of phylogenetic diversity were found from June to October. The different diversity facets of this assemblage were positively correlated with precipitation and minimum temperature, whereas maximum temperature showed no influence. In addition, we found that this odonate diversity was higher than most Mexican localities with tropical dry forest (TDF) studied. New information: We continue our efforts to describe the patterns of richness, diversity and abundance of some insect groups associated with the tropical dry forest ecosystem in Mexico, following a latitudinal gradient of the distribution of this ecosystem in the country. Our emphasis here was to evaluate the spatial and temporal patterns of richness and diversity of an Odonata assemblage from Jalisco, Mexico.

17.
J Math Biol ; 88(4): 40, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38446152

RESUMO

Phylogenetic diversity is a popular measure for quantifying the biodiversity of a collection Y of species, while phylogenetic diversity indices provide a way to apportion phylogenetic diversity to individual species. Typically, for some specific diversity index, the phylogenetic diversity of Y is not equal to the sum of the diversity indices of the species in Y. In this paper, we investigate the extent of this difference for two commonly-used indices: Fair Proportion and Equal Splits. In particular, we determine the maximum value of this difference under various instances including when the associated rooted phylogenetic tree is allowed to vary across all rooted phylogenetic trees with the same leaf set and whose edge lengths are constrained by either their total sum or their maximum value.


Assuntos
Biodiversidade , Folhas de Planta , Filogenia
18.
Glob Chang Biol ; 30(3): e17234, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38469998

RESUMO

Rapid biodiversity losses under global climate change threaten forest ecosystem functions. However, our understanding of the patterns and drivers of multiple ecosystem functions across biodiversity gradients remains equivocal. To address this important knowledge gap, we measured simultaneous responses of multiple ecosystem functions (nutrient cycling, soil carbon stocks, organic matter decomposition, plant productivity) to a tree species richness gradient of 1, 4, 8, 16, and 32 species in a young subtropical forest. We found that tree species richness had negligible effects on nutrient cycling, organic matter decomposition, and plant productivity, but soil carbon stocks and ecosystem multifunctionality significantly increased with tree species richness. Linear mixed-effect models showed that soil organisms, particularly arbuscular mycorrhizal fungi (AMF) and soil nematodes, elicited the greatest relative effects on ecosystem multifunctionality. Structural equation models revealed indirect effects of tree species richness on ecosystem multifunctionality mediated by trophic interactions in soil micro-food webs. Specifically, we found a significant negative effect of gram-positive bacteria on soil nematode abundance (a top-down effect), and a significant positive effect of AMF biomass on soil nematode abundance (a bottom-up effect). Overall, our study emphasizes the significance of a multitrophic perspective in elucidating biodiversity-multifunctionality relationships and highlights the conservation of functioning soil micro-food webs to maintain multiple ecosystem functions.


Assuntos
Ecossistema , Micorrizas , Cadeia Alimentar , Árvores , Solo/química , Biodiversidade , Plantas , Carbono
19.
Curr Biol ; 34(6): 1271-1283.e4, 2024 03 25.
Artigo em Inglês | MEDLINE | ID: mdl-38460512

RESUMO

Madagascar is a biogeographically unique island with a remarkably high level of endemism. However, endemic taxa in Madagascar are massively threatened due to unprecedented pressures from anthropogenic habitat modification and climate change. A comprehensive phylogeny-based biodiversity evaluation of the island remains lacking. Here, we identify hotspots of taxonomic and phylogenetic plant diversity and neo- and paleo-endemism by generating a novel dated tree of life for the island. The tree is based on unprecedented sampling of 3,950 species (33% of the total known species) and 1,621 genera (93% of the total known genera and 69% of endemic genera) of Malagasy vascular plants. We find that island-endemic genera are concentrated in multiple lineages combining high taxonomic and phylogenetic diversity. Integrating phylogenetic and geographic distribution data, our results reveal that taxon richness and endemism are concentrated in the northern, eastern, and southeastern humid forests. Paleo-endemism centers are concentrated in humid eastern and central regions, whereas neo-endemism centers are concentrated in the dry and spiny forests in western and southern Madagascar. Our statistical analysis of endemic genera in each vegetation region supports a higher proportion of ancient endemic genera in the east but a higher proportion of recent endemic genera in the south and west. Overlaying centers of phylogenetic endemism with protected areas, we identify conservation gaps concentrated in western and southern Madagascar. These gaps should be incorporated into conservation strategies to aid the protection of multiple facets of biodiversity and their benefits to the Malagasy people.


Assuntos
Biodiversidade , Ecossistema , Plantas , Madagáscar , Filogenia
20.
Proc Biol Sci ; 291(2018): 20232705, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38444334

RESUMO

The correct identification of variables affecting parasite diversity and assemblage composition at different spatial scales is crucial for understanding how pathogen distribution responds to anthropogenic disturbance and climate change. Here, we used a database of avian haemosporidian parasites to test how the taxonomic and phylogenetic diversity and phylogenetic structure of the genera Plasmodium, Haemoproteus and Leucocytozoon from three zoogeographic regions are related to surrogate variables of Earth's energy input, habitat heterogeneity (climatic diversity, landscape heterogeneity, host richness and human disturbance) and ecological interactions (resource use), which was measured by a novel assemblage-level metric related to parasite niche overlap (degree of generalism). We found that different components of energy input explained variation in richness for each genus. We found that human disturbance influences the phylogenetic structure of Haemoproteus while the degree of generalism explained richness and phylogenetic structure of Plasmodium and Leucocytozoon genera. Furthermore, landscape attributes related to human disturbance (human footprint) can filter Haemoproteus assemblages by their phylogenetic relatedness. Finally, assembly processes related to resource use within parasite assemblages modify species richness and phylogenetic structure of Plasmodium and Leucocytozoon assemblages. Overall, our study highlighted the genus-specific patterns with the different components of Earth's energy budget, human disturbances and degree of generalism.


Assuntos
Haemosporida , Especificidade de Hospedeiro , Humanos , Animais , Filogenia , Efeitos Antropogênicos , Aves
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