Showing papers in "Plant Ecology in 2023"

Construction of an ecological model of Sambucus javanica blume in China under different climate scenarios based on maxent model

Abstract: Sambucus javanica Blume is a Chinese native medicinal plant with high medicinal value. In this study, the MaxEnt model was used to explore the relationship between the geographical distribution of S. javanica and environmental factors, and to construct the distribution pattern of S. javanica under different climate scenarios. The results showed that the environmental conditions suitable for the distribution of S. javanica were as follows: precipitation in June ranged from 156.36 to 383.25 mm; solar radiation in December ranged from 6750.00 to 10,521.00 kJm−2day−1; isothermality ranged from 24.06 to 35.50; precipitation of warmest quarter ranged from 447.92 to 825.00 mm. Among them, precipitation and temperature were the key environmental factors affecting the distribution patterns of S. javanica. This plant could grow well mainly in two regions in China, covering a total area of 2.73 × 106 km2. The first region mainly consists of Guizhou, western Hubei, southeastern Chongqing, southwestern Hunan, northern Guangxi, and a small part of eastern Yunnan. The second region mainly consists of Zhejiang, southern Anhui, and northern Fujian. Under the future SSP126 and SSP585 scenarios, potentially suitable habitats in the eastern part of the potential distribution of S. javanica (Jiangxi, Fujian, Zhejiang, and Anhui) might be at risk of habitat fragmentation. Future climate change might have little effect on the distribution areas of S. javanica. But its suitable distribution has a tendency shift to higher altitude areas. Based on the result of this study, real-time monitoring of wild groups of S. javanica is now recommended to protect its genetic diversity. These findings are supposed to promote the effective conservation and utilization of S. javanica in the future.

Translocations of threatened plants in the Mediterranean Basin: current status and future directions

Abstract: Abstract The Mediterranean Basin is one of the World’s plant diversity hotspots and a region prone to several anthropic pressures, besides being one of the World’s areas most susceptible to climate change. In this region, which hosts a high percentage of threatened species, there has been a large increase in practical conservation actions to prevent the extinction of many plants or improve their conservation status. In this framework, plant translocations have become increasingly important. To obtain a picture of the status and to depict possible directions, data on plant translocations was collected through the available databases, national experts, and the grey literature available online. Overall, a list of 836 translocations relating to 572 plant species was found. These actions are mainly concentrated in Spain, France, and Italy (c. 87%) and, except for some pioneering actions, translocations have strongly increased starting from 2010. A subsequent in-depth bibliographic search of the scientific databases was conducted to determine how much information about plant translocations was documented in the scientific literature. This search resulted in a list of 133 peer-reviewed papers, of which only 17 describing one or more translocations and, as a whole, reporting 101 experiences carried out on 56 plant species. Our research highlighted a great discrepancy between the scarce scientific documentation in comparison to the large number of practical conservation actions carried out. The great experience gained in these translocations constitutes an enormous heritage potentially available to implement the necessary conservation actions to preserve the plant diversity of the Mediterranean Basin.

Climate change might lead to substantial niche displacement in one of the most biodiverse regions in the world

Abstract: Abstract Climatic niches are key factors driving global and regional species distributions. The Atlantic Forest domain is considered one of the most threatened biomes in the world, and one of the main centres of plant diversity and endemism in the Neotropics. Of the over 13,000 species of vascular plants, nearly 15% are vascular epiphytes. Here we analysed for the first time how current epiphyte niches will be affected under future climate projections (SSP126 and SSP585) within 1.5 million km 2 of Atlantic Forest in South America. Using the largest database of vascular epiphytes to date (n = 1521 species; n = 75,599 occurrence records) and ordination models, we found that the Atlantic Forest is expected to become warmer and drier and that up to 304 epiphyte species (20%) will have their average niche positions displaced outside the available climate space by the years 2040–2100. The findings from this study can help to inform ongoing legislative conservation efforts in one of the world’s most biodiverse regions.

Dispersal and persistence traits inform long-term herbaceous plant community change in encroached savannas

Abstract: Savanna plant communities are highly diverse, characterized by an open-canopy structure with rich herbaceous diversity, and maintained by frequent low-intensity fire and grazing. Due to habitat loss and fragmentation, savannas are globally threatened, with less than 1% of former oak savanna land cover found in the Midwestern United States remaining. In remnant oak savannas, loss of fire and grazing has led to woody encroachment and canopy closure over the past century with cascading consequences for the taxonomic composition. Whether these taxonomic changes can be broadly predicted using species functional traits (morpho-physio-phenological characteristics that impact the fitness of a species) is a key question. We ask whether the impacts of woody encroachment on herbaceous species can be predicted from species’ abilities to persist (avoid extinction) and disperse (colonize new areas). Specifically, we pair persistence traits (e.g., clonality, belowground storage) and dispersal traits (e.g., seed mass, dispersal mode, flowering height) with a rare 60-year dataset from oak savannas in Wisconsin, USA to understand how the representation of these traits has changed in the herbaceous community over time. Over 60 years, change in species composition was explained both by dispersal abilities and persistence traits; small-seeded species reliant on unassisted dispersal and moderately clonal species experienced the greatest losses. These changes in functional composition are likely due to increased woody encroachment, which may impede propagule production and movement. Restoration efforts need to prioritize species that are dispersal limited and those that create fine fuels, which aid the persistence of fire-maintained open habitat savannas.

Intraspecific trait variation and species turnover in successional tropical forests: assessing trait imputation for community-weighted means

Abstract: Accounting for intraspecific trait variation (ITV) is crucial to plant ecology for vegetation modeling efforts. ITV can be substantial; however, it remains unclear how ITV influences community-weighted mean (CWM) trait estimates. We use leaf and root trait data from 423 trees of 72 species from 15 Angiosperm families in combination with community data from 164 25 × 25 m plots comprising 580 species to evaluate the contributions of ITV and compositional turnover to CWMs, comparing unlogged primary tropical forest to selectively logged and clear-cut secondary tropical forest. We also examine the effect of imputing missing trait values using phylogenetic generalized linear modeling (PhyloPars) on CWMs. For six of the seven traits, ITV negatively covaried with community compositional turnover to generate larger CWM differences between forest types than observed if ITV was not integrated. For example, plot average-weighted mean specific leaf area was 10.7 and 10.4 m2 kg−1 for primary and secondary forests, not accounting for ITV, but shifted to 9.8 and 11.1 m2 kg−1 after doing so. Our results from 72 species assemblages were largely consistent with results using phylogenetically imputed traits for the entire community. The contribution of ITV to CWMs ranged from 25 to 75%, with ITV, not species turnover, driving CWM trait variation among successional forest types. CWM trait estimates became more conservative with forest age, whereas ITV for many traits showed an opposing acquisitive shift (i.e., increasing in leaf area or root length) and because of negative covariation between ITV and species turnover, weighted mean trait differences between successional forest types increased.

Three-way species interactions reverse the positive pairwise effects of two natives on an exotic invader

Abstract: Abstract The disruptive effects of tertiary species on otherwise positive pairwise species interactions (e.g. context-dependent parasitism in pollinator syndromes) is well-known. However, few—if any—studies have investigated how invasive plants affect interactions between facilitative plants and their native plant communities. Further, if tertiary invasive species can change interactions among native species from positive to negative, then a tertiary native should be capable of the same phenom for pairwise interactions between natives and invasives. Our previous research indicates invasive black mustard ( Brassica nigra ) changes interaction signs for otherwise positive species interactions between the dominant, native facilitator California buckwheat ( Eriogonum fasciculatum ) and its co-dominant beneficiary California sagebrush ( Artemisia californica ) in semi-arid California coastal sage scrub habitat. Here, E. fasciculatum and A. californica seedlings increased B. nigra shoot growth in pairwise species interactions in the greenhouse. However, in three-way species interactions, E. fasciculatum and A. californica together reduced B. nigra SLA, height, and reproductive potential while not increasing shoot DW. In three-way species interactions, B. nigra did not significantly reduce E. fasciculatum facilitation of A. californica . Also surprisingly, light competition with B. nigra resulted in an increase in A. californica height , which reduced the negative effects of A. californica light competition on shade-intolerant E. fasciculatum. In an additive field experiment, A. californica protected E. fasciculatum from facilitating germination and growth of B. nigra when water competition was minimized. Taken together, this study demonstrates the importance of studying species interactions between competitive, native perennials in the current ecological context of invaded ecosystems.

Applying simple genomic workflows to optimise practical plant translocation outcomes

Abstract: Abstract Translocation is an important conservation tool for reducing the probability of extinction of threatened plants. It is also becoming an increasingly common management practice, as habitats are destroyed and climate change pushes more plants beyond the limits of their tolerances. Here we outline the case for informing translocations with dedicated genomic data. We begin by describing principles for using genomic and genetic approaches to enhance the efficiency and success of translocation actions. This includes ensuring that translocated populations are adaptively representative, diverse, and composed (to the greatest possible extent) of unrelated individuals. We then use two Australian case studies to illustrate how these principles have been applied in practice and in a resource-efficient way. For Prostanthera densa , we describe how genomic data have quantitatively informed complex decisions, such as whether, and how extensively, to mix individuals from spatially isolated populations in translocated populations. For Fontainea oraria , genomic data have been used during post-translocation monitoring to confirm that newly established populations incorporate and recombine the little diversity that remained in wild individuals. Overall, we illustrate how a simple workflow can support the development and planning of genomic studies and translocation activities in tandem. In order to ensure greater adoption of translocation genomic workflows, funding bodies in charge of biodiversity management and conservation must direct the necessary resources towards them.

Asymmetric inter-specific competition between invasive Phytolacca americana and its native congener

Abstract: Interspecific competition determines the invasive capability of alien plants. Phytolacca americana, one of the most destructive invasive plants in China, was first discovered and recorded in China in 1935. Since its arrival, the rapid expansion of the species has driven out a native congener, Phytolacca acinosa. In this study, we assessed the competitive interaction of the invasive P. americana the native P. acinosa in a pot experiment at Yunnan University. Our results indicate that P. americana severely inhibits the growth and reproduction of P. acinosa. Furthermore, P. americana demonstrated a superior resistance against both insect predation and bacterial infection. We suggest that this improved tolerance against herbivory and potentional pathogen damage may be a cornerstone to the invasive success of Phytolacca americana.

Development of negative soil feedback by an invasive plant near the northern limit of its invaded range

Abstract: Invasions at high latitudes are recognized as an emerging threat to native biodiversity, but non-native plants still are scarce in northern Canada. One factor potentially inhibiting further invasions may be below-ground interactions; in particular, it is unclear whether interactions with soil biota are likely to help or hinder the spread of new species into often challenging northern soils. In the Canadian subarctic, the non-native plant Linaria vulgaris has invaded human-disturbed soils in the town of Churchill, Manitoba (58.8°N) but for decades has failed to spread into natural communities. One explanation for this stasis might be greater resistance by soil communities in uninvaded areas relative to areas where this plant is established; however, no local evidence for plant-soil feedbacks exists. In one of the first papers to test the potential role of plant-soil feedbacks in an invasion at high latitudes, we planted L. vulgaris in soil serially inoculated with live and sterilized field-collected soil sampled from invaded or uninvaded sites, and measured plant performance (biomass) over three iterations. We also conducted soil chemical analyses to determine whether pH, and carbon, nitrogen, and phosphorous contents differ between invaded and uninvaded areas. There was no initial difference in biomass between inoculation treatments in the first two iterations. However, by iteration 3, we found that sterilization significantly increased L. vulgaris biomass in invaded soils, indicating feedback becomes negative in invaded soils compared to uninvaded soils. Soil chemistry did not differ significantly between invaded and uninvaded soils, though there was a tendency for invaded soils to contain more carbon and nitrogen. These results do not support the hypothesis that L. vulgaris is absent from uncolonized sites because soil communities resist invasion. Instead, they provide evidence that L. vulgaris is inhibited by plant-soil feedbacks in invaded soils, while feedbacks in native-dominated soils are not a barrier to further local spread. Thus, explanations for the restriction of this species must lie elsewhere.

Multifaceted diversity changes reveal community assembly mechanisms during early stages of post-logging forest succession

Abstract: Abstract Plant succession is a fundamental process of vegetation recovery on disturbed sites. Elucidating its mechanisms remains a challenge as succession is influenced by stochastic and deterministic processes related to abiotic and biotic filters. Here, we use a multifaceted diversity approach to reveal mechanisms of successional changes in European oak-hornbeam forests during the first 10 years after selective logging. As the mechanisms controlling succession may depend upon initial abiotic conditions and colonization potential of the surrounding vegetation, we compare changes in taxonomic, functional, and phylogenetic diversity between clearings connected with open habitats and those isolated inside forests. Despite fewer dispersal barriers and higher biomass production in connected clearings, similar mechanisms initially governed succession in post-logging sites. Both clearings had low taxonomic and functional diversity in the first year of succession, as evidenced by significant trait convergence, caused by the legacy of interactions between overstory and understory vegetation in pre-disturbance closed-canopy forests. Colonization by short-lived and light-demanding species in the second and third years after logging has markedly increased the overall taxonomic and functional diversity, as evidenced by significant trait divergence. Connected clearings had higher functional but lower taxonomic and phylogenetic diversity than isolated clearings from the fourth to ten years of succession, probably due to intense competition in more productive habitats. All diversity facets markedly decreased in the last years due to increasing asymmetric competition from regenerating trees. The successional processes were largely deterministic, driven by species’ life-history strategies and biotic interactions (competition) rather than abiotic constraints and stochastic events.