Spatial isolation impacts pollinator visitation and reproductive success of a threatened self-incompatible Mediterranean tree

Pollination service is crucial to achieve successful plant sexual reproduction and long-term population persistence. This pollination service can be affected by plant conspecific density and also by intrinsic features of individuals related to their flowering phenology and floral display. However, studies examining intrinsic and extrinsic traits on pollinator visitation and reproductive success of Mediterranean trees with limited reproduction are still scarce. We analyzed the effects of plant isolation, flowering phenology, flower weight and tree size on flower visitation probability, flowering patch visitation probability, fruit set and crop size. To this end, we intensively monitored pollinator visitation and fruit production of 67 (in 2019) and 73 (in 2020) Pyrus bourgaeana Decne trees within a threatened Mediterranean population. Our results revealed that isolated individuals received more pollinators than those on conspecific aggregations, suggesting intraspecific competition for pollinators in dense flowering neighborhoods. However, fruit set was higher in trees close to flowering conspecifics despite having fewer visits from pollinators, suggesting pollen limitation but not pollinator limitation in spatially isolated trees. Interestingly, we found increased crop sizes in spatially isolated trees which could be related to reduced intraspecific competition for resources in low-density neighborhoods (water, nutrients) and/or to higher reproductive investment (i.e. higher flower production). Overall, our results indicated pollen but not pollinator limitation in spatially isolated trees. Under this scenario of sexual reproduction mediated by pollinators, our findings stress the relevance of individuals’ spatial distribution for self-incompatible trees exhibiting low individuals’ densitiesinfo:eu-repo/semantics/publishedVersio

Interspecific interactions among functionally diverse frugivores and their outcomes for plant reproduction: a new approach based on camera-trap data and tailored null models

Research ArticleThe study of plant-frugivore interactions is essential to understand the ecology and evolution of many plant communities. However, very little is known about how interactions among frugivores indirectly affect plant reproductive success. In this study, we examined direct interactions among vertebrate frugivores sharing the same fruit resources. Then, we inferred how the revealed direct interspecific interactions could lead to indirect (positive or negative) effects on reproductive success of fleshy fruited plants. To do so, we developed a new analytical approach that combines camera trap data (spatial location, visitor species, date and time, activity) and tailored null models that allowed us to infer spatial-temporal interactions (attraction, avoidance or indifference) between pairs of frugivore species. To illustrate our approach, we chose to study the system composed by the Mediterranean dwarf palm, Chamaerops humilis, the Iberian pear tree, Pyrus bourgaeana, and their shared functionally diverse assemblages of vertebrate frugivores in a Mediterranean area of SW Spain. We first assessed the extent to which different pairs of frugivore species tend to visit the same or different fruiting individual plants. Then, for pairs of species that used the same individual plants, we evaluated their spatial-temporal relationship. Our first step showed, for instance, that some prey frugivore species (e.g. lagomorphs) tend to avoid those C. humilis individuals that were most visited by their predators (e.g. red foxes). Also, the second step revealed temporal attraction between large wild and domestic frugivore ungulates (e.g. red deer, cows) and medium-sized frugivores (e.g. red foxes) suggesting that large mammals could facilitate the C. humilis and P. bourgaeana exploitation to other smaller frugivores by making fruits more easily accessible. Finally, our results allowed us to identify direct interaction pathways, that revealed how the mutualistic and antagonistic relations between animal associates derived into indirect effects on both plants seed dispersal success. For instance, we found that large-sized seed predators (e.g. ungulates) had a direct positive effect on the likelihood of visits by legitimate seed dispersers (e.g. red foxes) to both fleshy fruited plants. Then, seed predators showed an indirect positive effect on the plants’ reproductive Our new analytical approach provides a widely applicable framework for further studies on multispecies interactions in different systems beyond plant-frugivore interactions, including plant-pollinator interactions, the exploitation of plants by herbivores, and the use of carcasses by vertebrate scavengersinfo:eu-repo/semantics/publishedVersio

CARB-ES-19 Multicenter Study of Carbapenemase-Producing Klebsiella pneumoniae and Escherichia coli From All Spanish Provinces Reveals Interregional Spread of High-Risk Clones Such as ST307/OXA-48 and ST512/KPC-3

ObjectivesCARB-ES-19 is a comprehensive, multicenter, nationwide study integrating whole-genome sequencing (WGS) in the surveillance of carbapenemase-producing K. pneumoniae (CP-Kpn) and E. coli (CP-Eco) to determine their incidence, geographical distribution, phylogeny, and resistance mechanisms in Spain.MethodsIn total, 71 hospitals, representing all 50 Spanish provinces, collected the first 10 isolates per hospital (February to May 2019); CPE isolates were first identified according to EUCAST (meropenem MIC > 0.12 mg/L with immunochromatography, colorimetric tests, carbapenem inactivation, or carbapenem hydrolysis with MALDI-TOF). Prevalence and incidence were calculated according to population denominators. Antibiotic susceptibility testing was performed using the microdilution method (EUCAST). All 403 isolates collected were sequenced for high-resolution single-nucleotide polymorphism (SNP) typing, core genome multilocus sequence typing (cgMLST), and resistome analysis.ResultsIn total, 377 (93.5%) CP-Kpn and 26 (6.5%) CP-Eco isolates were collected from 62 (87.3%) hospitals in 46 (92%) provinces. CP-Kpn was more prevalent in the blood (5.8%, 50/853) than in the urine (1.4%, 201/14,464). The cumulative incidence for both CP-Kpn and CP-Eco was 0.05 per 100 admitted patients. The main carbapenemase genes identified in CP-Kpn were blaOXA–48 (263/377), blaKPC–3 (62/377), blaVIM–1 (28/377), and blaNDM–1 (12/377). All isolates were susceptible to at least two antibiotics. Interregional dissemination of eight high-risk CP-Kpn clones was detected, mainly ST307/OXA-48 (16.4%), ST11/OXA-48 (16.4%), and ST512-ST258/KPC (13.8%). ST512/KPC and ST15/OXA-48 were the most frequent bacteremia-causative clones. The average number of acquired resistance genes was higher in CP-Kpn (7.9) than in CP-Eco (5.5).ConclusionThis study serves as a first step toward WGS integration in the surveillance of carbapenemase-producing Enterobacterales in Spain. We detected important epidemiological changes, including increased CP-Kpn and CP-Eco prevalence and incidence compared to previous studies, wide interregional dissemination, and increased dissemination of high-risk clones, such as ST307/OXA-48 and ST512/KPC-3

Time to Switch to Second-line Antiretroviral Therapy in Children With Human Immunodeficiency Virus in Europe and Thailand.

Background: Data on durability of first-line antiretroviral therapy (ART) in children with human immunodeficiency virus (HIV) are limited. We assessed time to switch to second-line therapy in 16 European countries and Thailand. Methods: Children aged <18 years initiating combination ART (≥2 nucleoside reverse transcriptase inhibitors [NRTIs] plus nonnucleoside reverse transcriptase inhibitor [NNRTI] or boosted protease inhibitor [PI]) were included. Switch to second-line was defined as (i) change across drug class (PI to NNRTI or vice versa) or within PI class plus change of ≥1 NRTI; (ii) change from single to dual PI; or (iii) addition of a new drug class. Cumulative incidence of switch was calculated with death and loss to follow-up as competing risks. Results: Of 3668 children included, median age at ART initiation was 6.1 (interquartile range (IQR), 1.7-10.5) years. Initial regimens were 32% PI based, 34% nevirapine (NVP) based, and 33% efavirenz based. Median duration of follow-up was 5.4 (IQR, 2.9-8.3) years. Cumulative incidence of switch at 5 years was 21% (95% confidence interval, 20%-23%), with significant regional variations. Median time to switch was 30 (IQR, 16-58) months; two-thirds of switches were related to treatment failure. In multivariable analysis, older age, severe immunosuppression and higher viral load (VL) at ART start, and NVP-based initial regimens were associated with increased risk of switch. Conclusions: One in 5 children switched to a second-line regimen by 5 years of ART, with two-thirds failure related. Advanced HIV, older age, and NVP-based regimens were associated with increased risk of switch

Seed dispersers inflate kinship in a bout, but promote genetic admixture within the neighbourhood in the long-term

Trabajo presentado en el 7th Frugivores and Seed Dispersal Symposium, celebrado en la India del 2 al 6 de marzo de 2020

Unmasking the perching effect of the pioneer Mediterranean dwarf palm Chamaerops humilis L.

Although farmlands are the most extensive terrestrial biomes, the abandonment of traditional agriculture in many parts of the world has brought opportunities and challenges for the restoration of such human-disturbed habitats. Seed arrival is a crucial necessary ecological process during plant recolonization that can be enhanced by the use of the so-called “perch plants”. Little is known, however, about whether the seed arrival via frugivorous birds is affected by the spatial distribution of the perch plants in disturbed habitats. To evaluate several spatial aspects of “perching” effect, we used a spatially explicit approach in two disturbed plots within the Doñana National Park (SW Spain). Specifically, we chose as study system the pioneer Mediterranean dwarf palm Chamaerops humilis L., which is often used as a perch by a variety of frugivorous bird species. A total of 289 C. humilis individuals were sampled in search of bird feces (N = 2998) and dispersed seeds (N = 529). Recorded seeds belonged to six different woody species from five different families. Nine bird species from six different families were recorded using C. humilis as perches. GLMs analyses indicated that taller C. humilis males with higher numbers of spatially associated woody species received more dispersed seeds. We detected a random spatial structure of bird feces and dispersed seeds in one study plot, while a nonrandom spatial structure was found in the other one, where isolated C. humilis received a higher number of bird feces and dispersed seeds than expected under spatial null models. The difference in spatial patterns between both study plots could relate, among other factors, to their different state of development in the ecological succession. Most of dispersed seeds were concentrated in a small number of C. humilis individuals, usually male and large ones, that acted as “hotspots” of seed arrival. The fact that frugivorous birds in one study site visited most often isolated C. humilis questions the aggregated spatial structure of revegetation designs typically used in restoration projects. This study reveals novel spatial aspects of the “perching” effect which could be helpful in the restoration of human-disturbed habitats worldwide.This work was supported by the Portuguese Foundation for Science and Technology to PJG (SFRH/BD/130527/2017) and by a grant of the Spanish Ministry of Education and Science to JMF (PGC2018-094808-B-I00). Logistic and technical support was provided by ICTS-RBD. The authors acknowledge support of the publication fee by the CSIC Open Access Publication Support Initiative through its Unit of Information Resources for Research (URICI

Unmasking the perching effect of the pioneer Mediterranean palm Chamaerops humilis L.

Trabajo presentado en la 7th Seed Ecology Conference of the International Society for Seed Science, celebrada en Gijón (España) del 06 al 09 de septiembre de 2022

The endemic Mediterranean dwarf palm boosts the recolonization of old-fields: Implications for restoration

Understanding the mechanisms underlying the recolonization of old-fields is critical to promote the recovery of the ecosystem functioning, particularly in regions where agricultural abandonment has increased in the last 60 years. Given that seed arrival and seedling survival often limit the recolonization process by woody species in many Mediterranean habitats, the ‘perching’ and ‘nursing’ effects exerted by some pioneer species could be crucial for the restoration of such abandoned lands. We examined the role of an endemic Mediterranean palm (Chamaerops humilis) on the recolonization of old-fields by woody species in southern Iberian Peninsula. We chose three independent old-fields differing in their shrub encroachment levels. To identify potential facilitation by C. humilis, we used a spatially-explicit approach and analyzed its spatial associations with ten common woody species (e.g. Asparagus spp., Daphne gnidium, Olea europaea var. sylvestris, Pyrus bourgaeana). We detected positive spatial associations between C. humilis and woody species at small-scale (1–5 m) in the three plots. Most of such small-scale associations were linked to the bird-dispersal of woody species. Nonetheless, there were marked differences among plots in spatial associations between C. humilis and woody plants, being Asparagus spp. the only species positively associated with C. humilis within the three studied old-fields. These species-specific differences were likely related to variations among old-fields in encroachment level and the legacy of human management. Such small-scales spatial associations between C. humilis and woody species across Iberian old-fields were linked to the perching and nursing effects exerted by the palm. We emphasize the strong potential of this pioneer Mediterranean palm for the restoration of native ecosystems and the recovery of ecosystems services.This work was supported by the Portuguese Foundation for Science and Technology, PJG (SFRH/BD/130527/2017), ARC (SFRH/BPD/ 115781/2016) and JMF (IF/00728/2013)

Coping with changing plant–plant interactions in restoration ecology: Effect of species, site, and individual variation

[Question]: Nurse–beneficiary plant interactions are often used to restore degraded habitats. However, whether and how shifts in plant–plant interactions along the facilitation–competition continuum alter revegetation success has been seldom considered. To test whether and how shifts in plant–plant interactions (due to woody species identity, study site, early life stage, and individual nurse) might alter plant recruitment and thus the success of revegetation projects, we chose a system comprising the Mediterranean dwarf palm (Chamaerops humilis) and seven common woody plant species. [Location]: Two human-degraded sites within Doñana National Park (southwestern Spain). [Methods]: We carried out several well-replicated field experiments to compare plant performance (seed survival, seedling emergence, seedling survival, seedling recruitment) in the presence and absence of Chamaerops humilis. [Results]: Chamaerops humilis had marked effects on the performance of woody species that, however, changed among life stages. Depending on woody species identity, seed survival was up to 193 times greater in adjacent open spaces than beneath Chamaerops humilis. Conversely, seedling survival and recruitment were up to 19 times greater beneath Chamaerops humilis than in open spaces. Importantly, none of the studied woody species showed greater accumulated recruitment in open spaces than beneath Chamaerops humilis. Interestingly, we found strong inter-individual palm variation in the sign and strength of their effect on woody plant performance. [Conclusions]: We found strong seed–seedling conflicts the strength of which was species-specific. The strong inter-individual palm variation depicts a facilitation–competition continuum with important implications for restoration. We propose several management recommendations across different hierarchical levels (i.e., from individuals to communities) that may increase plant recruitment and therefore the success of revegetation projects. Our results are particularly relevant for restoring arid, semi-arid and alpine landscapes worldwide where the nurse–beneficiary plant interactions are critical to ameliorating stressful conditions.This work was supported by the Portuguese Foundation for Science and Technology to PJG (SFRH/BD/130527/2017) and ARC (SFRH/BPD/115781/2016); and by a grant of the Spanish Ministry of Education and Science to JMF (PGC2018-094808-B- I00)

Facilitation, restoration, and the mutualism-antagonism continuum

Trabajo presentado en el 9th World Conference on Ecological Restoration. A new global trajectory: catalyzing change through the UN Decade on Ecosystem Restoration, celebrado en modalidad virtual del 21 al 24 de junio de 2021