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1.
Entropy (Basel) ; 26(8)2024 Jul 30.
Article in English | MEDLINE | ID: mdl-39202116

ABSTRACT

This paper proposes an advancement in the application of a Technical Vision System (TVS), which integrates a laser scanning mechanism with a single light sensor to measure 3D spatial coordinates. In this application, the system is used to scan and digitalize objects using a rotating table to explore the potential of the system for 3D scanning at reduced resolutions. The experiments undertaken searched for optimal scanning windows and used statistical data filtering techniques and regression models to find a method to generate a 3D scan that was still recognizable with the least amount of 3D points, balancing the number of points scanned and time, while at the same time reducing effects caused by the particularities of the TVS, such as noise and entropy in the form of natural distortion in the resulting scans. The evaluation of the experimentation results uses 3D point registration methods, joining multiple faces from the original volume scanned by the TVS and aligning it to the ground truth model point clouds, which are based on a commercial 3D camera to verify that the reconstructed 3D model retains substantial detail from the original object. This research finds it is possible to reconstruct sufficiently detailed 3D models obtained from the TVS, which contain coarsely scanned data or scans that initially lack high definition or are too noisy.

2.
J Imaging ; 10(5)2024 Apr 28.
Article in English | MEDLINE | ID: mdl-38786560

ABSTRACT

Puerto de Cajas serves as a vital high-altitude passage in Ecuador, connecting the coastal region to the city of Cuenca. The stability of this rocky massif is carefully managed through the assessment of blocks and discontinuities, ensuring safe travel. This study presents a novel approach, employing rapid and cost-effective methods to evaluate an unexplored area within the protected expanse of Cajas. Using terrestrial photogrammetry and strategically positioned geomechanical stations along the slopes, we generated a detailed point cloud capturing elusive terrain features. We have used terrestrial photogrammetry for digitalization of the slope. Validation of the collected data was achieved by comparing directional data from Cloud Compare software with manual readings using a digital compass integrated in a phone at control points. The analysis encompasses three slopes, employing the SMR, Q-slope, and kinematic methodologies. Results from the SMR system closely align with kinematic analysis, indicating satisfactory slope quality. Nonetheless, continued vigilance in stability control remains imperative for ensuring road safety and preserving the site's integrity. Moreover, this research lays the groundwork for the creation of a publicly accessible 3D repository, enhancing visualization capabilities through Google Virtual Reality. This initiative not only aids in replicating the findings but also facilitates access to an augmented reality environment, thereby fostering collaborative research endeavors.

3.
Am J Bot ; 111(5): e16322, 2024 05.
Article in English | MEDLINE | ID: mdl-38641895

ABSTRACT

PREMISE: Functional traits reflect species' responses to environmental variation and the breadth of their ecological niches. Fagus grandifolia and Oreomunnea mexicana have restricted distribution in upper montane cloud forests (1700-2000 m a.s.l.) in Mexico. These species were introduced into plantings at lower elevations (1200-1600 m a.s.l.) that have climates predicted for montane forests in 2050 and 2070. The aim was to relate morphological leaf traits to the ecological niche structure of each species. METHODS: Leaf functional traits (leaf area, specific leaf area [SLA], thickness, and toughness) were analyzed in forests and plantings. Atmospheric circulation models and representative concentration pathways (RCPs: 2.6, 4.5, 8.5) were used to assess future climate conditions. Trait-niche relationships were analyzed by measuring the Mahalanobis distance (MD) from the forests and the plantings to the ecological niche centroid (ENC). RESULTS: For both species, leaf area and SLA were higher and toughness lower in plantings at lower elevation relative to those in higher-elevation forests, and thickness was similar. Leaf traits varied with distance from sites to the ENC. Forests and plantings have different environmental locations regarding the ENC, but forests are closer (MD 0.34-0.58) than plantings (MD 0.50-0.70) for both species. CONCLUSIONS: Elevation as a proxy for expected future climate conditions influenced the functional traits of both species, and trait patterns related to the structure of their ecological niches were consistent. The use of distances to the ENC is a promising approach to explore variability in species' functional traits and phenotypic responses in optimal versus marginal environmental conditions.


Subject(s)
Climate Change , Fagus , Forests , Plant Leaves , Plant Leaves/physiology , Plant Leaves/anatomy & histology , Fagus/physiology , Fagus/anatomy & histology , Mexico , Ecosystem
4.
Sci Total Environ ; 915: 169829, 2024 Mar 10.
Article in English | MEDLINE | ID: mdl-38211851

ABSTRACT

Global sea levels, having risen by approximately 20 cm since the mid-19th century, necessitate a critical examination of their impacts on shoreline dynamics. This research evaluates the historical (1985-2022) and future shoreline changes in Conde County, Paraíba State, Brazil, an area of significant touristic interest. Employing Landsat satellite imagery, the study utilized the Digital Shoreline Analysis System (DSAS) and a Kalman filter algorithm for cloud removal, while also assessing land use and land cover changes using data from the MapBiomas Project for 2000, 2010, and 2020. These analyses informed projections of potential inundation under various sea-level rise (SLR) scenarios: 1, 2, 5, and 10 m. Key findings revealed a negative average coastline change rate of -0.27 m/year from 1985 to 2022, indicative of erosive trends likely accelerated by human activities. Long-term projections for 2032 and 2042 anticipate continued erosion in areas identified as highly vulnerable. The SLR scenario analysis underscores the urgent need for adaptive climate measures; while a 1- or 2-meter SLR presents limited immediate effects, a 5-meter rise could lead to significant inundation across key sectors, including urban and agricultural landscapes. The projected severity of a 10-meter SLR necessitates immediate, comprehensive interventions to safeguard both natural and human systems.

5.
Biota Neotrop. (Online, Ed. ingl.) ; 24(3): e20241619, 2024. tab, graf
Article in English | LILACS-Express | LILACS | ID: biblio-1568888

ABSTRACT

Abstract Montane ecosystems in South America harbor high levels of endemism typically with species that are often threatened. Here we investigated fruit and seed morphology, germination, and early growth parameters of Crinodendron brasiliense, an endangered and narrow endemic tree species of subtropical montane cloud forests in Southern Brazil. We obtained fruit and seed size and shape, number of lobes and number of seeds per fruit and evaluated germination and early growth parameters in a greenhouse. We tested the effect of different container types and parent plant on seed morphology, germination, and early growth. We also tested whether thermal scarification would improve germination rates. We showed that parent plant significantly influenced fruit and seed morphology as well as early growth rates. The germination rate of the species was extremely low (0.003-0.004%), which may be one important underlying cause of its small population size and restricted distribution. Thermal scarification was ineffective to improve the germination of seeds. Unexpectedly, container type significantly affected germination success, as seeds in trays germinated faster and in higher rates than seeds planted in seedbeds. Such result suggests a higher soil moisture could improve germination success. Our study is the first documented propagation of the species and provides essential aspects on the reproductive biology and early development of Crinodendron brasiliense. We highlight the urgent need for further research and collaborative conservation initiatives to prevent the extinction of this species.


Resumo Investigamos la morfología de frutos y semillas, la germinación y los parámetros del crecimiento inicial de Crinodendron brasiliense, una especie arbórea en peligro de extinción y endémica de los bosques montanos del sur de Brasil. Obtuvimos el tamaño y la forma de frutos y semillas, el número de lóbulos por fruto y el número de semillas por fruto, además de evaluar los parámetros de germinación y crecimiento inicial - desconocidos para la especie. Demostramos que la planta madre influyó significativamente en la morfología de frutos y semillas, así como en las tasas de crecimiento inicial. La tasa de germinación de la especie fue extremadamente baja (0.003-0.004%), lo que podría ser una causa importante para explicar su pequeño tamaño poblacional y restringida distribución. La escarificación térmica fue ineficaz para la germinación de semillas. Inesperadamente, el tipo de contenedor afectó significativamente el éxito de la germinación, ya que las semillas plantadas en bandejas germinaron más rápido y en tasas más altas que las semillas plantadas en semilleros. Tal resultado sugiere que una mayor humedad del suelo podría mejorar el éxito de la germinación. Nuestro estudio es el primer registro documentado de la propagación de esta especie y proporciona aspectos esenciales sobre la biología reproductiva y el desarrollo inicial de Crinodendron brasiliense. Destacamos la necesidad urgente de realizar más estudios e iniciativas de conservación colaborativas para evitar la extinción de esta especie.

6.
PhytoKeys ; 236: 53-64, 2023.
Article in English | MEDLINE | ID: mdl-38076004

ABSTRACT

Following the description of Eugenianaraveana in 2016 from the cloud forest of the Cofre de Perote volcano, Mexico, the doubt about the existence of another unlocalized and sympatric species of Eugenia remained. After years of searching, the second endemic species of the Cofre de Perote volcano, Eugeniasarahchazaroi, is presented here. It belongs to the section Umbellatae, and is described, illustrated, and compared with E.naraveana and E.coetzalensis, recently described from Veracruz, the second state with the highest diversity of Eugenia in Mexico. The species is only known from the type locality and is classified in the Critically Endangered CR B1+B2(a,biii) category of the IUCN Red List conservation assessments.

7.
PeerJ ; 11: e16345, 2023.
Article in English | MEDLINE | ID: mdl-37953770

ABSTRACT

Southern Mexico's tropical forests are home to the country's highest richness of mammal species; La Chinantla region is situated within this area, its name from the indigenous group residing in the area and holding territorial ownership, namely the Chinantecos. In La Chinantla, there are no Protected Areas; instead, there are Areas Destined Voluntarily for Conservation (ADVC) and "Voluntary Conservation Areas" (VCA), that are managed by local inhabitants through social consensus. These ADVC may function as an archipelago reserve, which represents regional diversity, including the social context, through complementarity. To verify its biodiversity, we analyzed the richness, composition, distribution, and conservation of wild mammals in the region. Records were obtained from four sources-primary data collection, databases, scientific literature, and community monitoring-and were organized into four zones based on altitudinal and vegetation gradients. We compared the diversity between zones for three categories of mammals: small (<100 gr.), bats, and medium and large (>100 gr.). 134 species were identified comprising 11 orders, 26 families and 86 genera. The zone with highest elevation presented the greatest species richness for the assemblage of mammals and terrestrial mammals, while the zone with the lowest elevation had the highest richness of bats. For each mammal category, the zone with the most species also registered the highest number of exclusive species. For the assemblage of mammals and for medium and large mammals, the similarity index was highest between the two intermediate zones, while for small mammals and bats, the greatest similarity occurred between the areas of higher altitude. The study region was found to have the second highest richness of mammals in Mexico. Finally, we suggest that the conservation proposals by indigenous people could function as a set of "islands" that promote the conservation of biodiversity, possibly as an Archipelago Reserve.


Subject(s)
Chiroptera , Humans , Animals , Mexico , Biodiversity , Mammals , Forests
8.
J Fungi (Basel) ; 9(9)2023 Sep 01.
Article in English | MEDLINE | ID: mdl-37755010

ABSTRACT

Mycena section Calodontes is macromorphologically distinguished by the collybioid or mycenoid basidiome, which is pink, purple, or violet, and, rarely, reddish-brown or yellowish. It is further characterized by the presence of oxalate crystals in the basal mycelium. The section comprises approximately 40 taxa, of which only five species and one variety exhibit bioluminescence. As part of an extensive study on Mycena sect. Calodontes in Mexico, specimens belonging to this section were collected and subjected to morphological analysis. Sequences from the nuclear internal transcribed spacer (ITS) of nuclear ribosomal DNA, RNA polymerase II large subunit Rpb1 (rpb1), and translation elongation factor-1α (Tef-1α) were generated to infer the relationships within Mycena sect. Calodontes using maximum likelihood and Bayesian inference. The phylogenetic evidence, along with the macro- and micromorphological features, supported the recognition of five new bioluminescent species within Mycena sect. Calodontes. Detailed macro- and micromorphological descriptions, line-drawing illustrations, and light and dark photographs of the new species are provided.

9.
Sensors (Basel) ; 23(15)2023 Aug 04.
Article in English | MEDLINE | ID: mdl-37571718

ABSTRACT

At present, modern society is experiencing a significant transformation. Thanks to the digitization of society and manufacturing, mainly because of a combination of technologies, such as the Internet of Things, cloud computing, machine learning, smart cyber-physical systems, etc., which are making the smart factory and Industry 4.0 a reality. Currently, most of the intelligence of smart cyber-physical systems is implemented in software. For this reason, in this work, we focused on the artificial intelligence software design of this technology, one of the most complex and critical. This research aimed to study and compare the performance of a multilayer perceptron artificial neural network designed for solving the problem of character recognition in three implementation technologies: personal computers, cloud computing environments, and smart cyber-physical systems. After training and testing the multilayer perceptron, training time and accuracy tests showed each technology has particular characteristics and performance. Nevertheless, the three technologies have a similar performance of 97% accuracy, despite a difference in the training time. The results show that the artificial intelligence embedded in fog technology is a promising alternative for developing smart cyber-physical systems.

10.
PeerJ ; 11: e15487, 2023.
Article in English | MEDLINE | ID: mdl-37304864

ABSTRACT

Background: Land use is a major factor determining stream water physicochemistry. However, most streams move from one land use type to another as they drain their watersheds. Here, we studied three land use scenarios in a tropical cloud forest zone in Mexico. We addressed three main goals, to: (1) assess how land use scenarios generate different patterns in stream physicochemical characteristics; (2) explore how seasonality (i.e., dry, dry-to-wet transition, and wet seasons) might result in changes to those patterns over the year; and (3) explore whether physicochemical patterns in different scenarios resulted in effects on biotic components (e.g., algal biomass). Methods: We studied Tropical Mountain Cloud Forest streams in La Antigua watershed, Mexico. Streams drained different three scenarios, streams with (1) an upstream section draining forest followed by a pasture section (F-P), (2) an upstream section in pasture followed by a forest section (P-F), and (3) an upstream forest section followed by coffee plantation (F-C). Physicochemistry was determined at the upstream and downstream sections, and at the boundary between land uses. Measurements were seasonal, including temperature, dissolved oxygen, conductivity, and pH. Water was analyzed for suspended solids, alkalinity, silica, chloride, sulfate, magnesium, sodium, and potassium. Nutrients included ammonium, nitrate, and phosphorus. We measured benthic and suspended organic matter and chlorophyll. Results: Streams presented strong seasonality, with the highest discharge and suspended solids during the wet season. Scenarios and streams within each scenario had distinct physicochemical signatures. All three streams within each scenario clustered together in ordination space and remained close to each other during all seasons. There were significant scenario-season interactions on conductivity (F = 9.5, P < 0.001), discharge (F = 56.7, P < 0.001), pH (F = 4.5, P = 0.011), Cl- (F = 12.2, P < 0.001), SO42- (F = 8.8, P < 0.001) and NH4+ (F = 5.4, P = 0.005). Patterns within individual scenarios were associated with stream identity instead of land use. Both P-F and F-C scenarios had significantly different physicochemical patterns from those in F-P in all seasons (Procrustes analysis, m12 = 0.05-0.25; R = 0.86-0.97; P < 0.05). Chlorophyll was significantly different among scenarios and seasons (F = 5.36, P = 0.015, F = 3.81, P = 0.42, respectively). Concentrations were related to physicochemical variables more strongly during the transition season. Conclusion: Overall, land use scenarios resulted in distinctive water physicochemical signatures highlighting the complex effects that anthropogenic activities have on tropical cloud forest streams. Studies assessing the effect of land use on tropical streams will benefit from assessing scenarios, rather than focusing on individual land use types. We also found evidence of the importance that forest fragments play in maintaining or restoring stream water physicochemistry.


Subject(s)
Anthropogenic Effects , Chlorides , Antigua and Barbuda , Biomass , Chlorophyll , Forests , Halogens
11.
Food Res Int ; 170: 112969, 2023 08.
Article in English | MEDLINE | ID: mdl-37316055

ABSTRACT

Dark kitchen is a delivery-only restaurant that operates without direct contact with the consumer, has no premises for local consumption and sells exclusively through online platforms. The main objective of this work is to identify and characterise dark kitchens in three urban centres featured in the most used food delivery app in Brazil. To this end, data collection was conducted in two phases. In the first phase, through data mining, we collected information from restaurants in three cities (Limeira, Campinas and São Paulo - Brazil) that were provided in the food delivery app. A total of 22,520 establishments were searched from the central point of each of the cities. In the second phase, the first 1,000 restaurants in each city were classified as dark kitchens, standard, or undefined restaurants. A thematic content analysis was conducted to further distinguish the dark kitchen models. Of the restaurants evaluated, 1,749 (65.2%) were classified as standard restaurants, 727 (27.1%) as dark kitchens, and 206 (7.7%) as undefined. In terms of the characteristics of dark kitchens, they were more dispersed and located further away from the central points compared to standard restaurants. Meals in dark kitchens were cheaper than in standard restaurants, and had a lower number of user reviews. Most of the dark kitchens in São Paulo served Brazilian dishes, while in the smaller cities, Limeira and Campinas, it was mainly snacks and desserts. Six different models of dark kitchen were identified: Independent dark kitchen; shell-type (hub); franchise; virtual kitchen in a standard restaurant (different menu); virtual kitchen in a standard restaurant (similar menu but different name); and home-based dark kitchen. The modelling approach and methodology used to classify and identify dark kitchens is considered a contribution to science as it allows a better understanding of this fast growing sector of the food industry. This in turn can help to develop management strategies and policies for the sector. Our study is also of value to regulators to determine their proliferation through urban planning and to promote appropriate guidelines for dark kitchens as they differ from standard restaurants.


Subject(s)
Meals , Restaurants , Brazil , Data Collection , Data Mining
12.
Sensors (Basel) ; 23(9)2023 Apr 30.
Article in English | MEDLINE | ID: mdl-37177615

ABSTRACT

The growing number of connected objects has allowed the development of new applications in different areas. In addition, the technologies that support these applications, such as cloud and fog computing, face challenges in providing the necessary resources to process information for different applications due to the highly dynamic nature of these networks and the many heterogeneous devices involved. This article reviews the existing literature on one of these challenges: resource allocation in the fog-cloud continuum, including approaches that consider different strategies and network characteristics. We also discuss the factors influencing resource allocation decisions, such as energy consumption, latency, monetary cost, or network usage. Finally, we identify the open research challenges and highlight potential future directions. This survey article aims to serve as a valuable reference for researchers and practitioners interested in the field of edge computing and resource allocation.

13.
Sensors (Basel) ; 23(9)2023 May 02.
Article in English | MEDLINE | ID: mdl-37177654

ABSTRACT

Cloud computing has become a popular delivery model service, offering several advantages. However, there are still challenges that need to be addressed when applying the cloud model to specific scenarios. Two of such challenges involve deploying and executing applications across multiple providers, each comprising several services with similar functionalities and different capabilities. Therefore, dealing with application distributions across various providers can be a complex task for a software architect due to the differing characteristics of the application components. Some works have proposed solutions to address the challenges discussed here, but most of them focus on service providers. To facilitate the decision-making process of software architects, we previously presented PacificClouds, an architecture for managing the deployment and execution of applications based on microservices and distributed in a multi-cloud environment. Therefore, in this work, we focus on the challenges of selecting multiple clouds for PacificClouds and choosing providers that best meet the microservices and software architect requirements. We propose a selection model and three approaches to address various scenarios. We evaluate the performance of the approaches and conduct a comparative analysis of them. The results demonstrate their feasibility regarding performance.

14.
PeerJ ; 11: e15415, 2023.
Article in English | MEDLINE | ID: mdl-37250721

ABSTRACT

Background: Soil microenvironmental variables showed an important key in α and ß-tree diversity in Neotropical montane oak forest. Thus, understanding the microenvironment fluctuation at small-fragment effects on tree diversity is crucial in maintaining the montane oak ecosystems. In this study, we hypothesized that within a relatively small-fragment (151.63 ha), tree α and ß-diversity fluctuate and specific soil microenvironmental factors could influence tree species diversity to answer three questions: Do tree α and ß-diversity differ among transects, even in a short-distance between them? Do microenvironmental variables influence tree diversity composition that occurs within a relict Neotropical montane oak forest? Is there a particular microenvironmental variable influencing tree species-specific? Methods: We established four permanent transects during a year in a relict Neotropical montane oak forest, we assessed tree diversity and specific microenvironmental variables (soil moisture, soil temperature, pH, depth litterfall and light incidence). This allowed us to evaluate how microenvironmental variables at small-fragment influence α and ß-tree diversity and tree species-specific. Results: Our results showed that α-diversity was not different among transects; however, ß-diversity of tree species was mostly explained by turnover and soil moisture, soil temperature, and light incidence were the microenvironmental variables that triggered the replacement (i.e., one species by another). Those variables also had effect on tree species-specific: Mexican beech (Fagus mexicana), Quebracho (Quercus delgadoana), Pezma (Cyathea fulva), Aguacatillo (Beilschmiedia mexicana), Pezma (Dicksonia sellowiana var. arachneosa), and Mountain magnolia (Magnolia schiedeana). Discussion: Our results confirm our hypothesis related to ß-diversity but not with α-diversity; however, the tree community structure of the diversity was similar among transects. Our study represents the first effort to evaluate and link the soil microenvironmental effect on tree α and ß-diversity, finding a high replacement in a small-fragment of Neotropical montane oak forest from eastern Mexico.


Subject(s)
Quercus , Trees , Soil/chemistry , Ecosystem , Forests
15.
PhytoKeys ; 224: 89-99, 2023.
Article in English | MEDLINE | ID: mdl-37251509

ABSTRACT

Liparisaltomayoënsissp. nov. is described, illustrated, and tentatively assigned to the Neotropical section Decumbentes on the basis of its branching, prostrate rhizomes and upright stems bearing several leaves. Vegetatively, the new species is distinguished by its short, upward stems bearing 3-6 leaves, these with undulate, translucent margins and reticulate, prominent veining on the upper surface. Florally, it is distinctive in the labellum with fleshy basal one-half provided with a central, rounded cavity limited on each side by a prominent, bilobulate ridge and apically by a lunate ridge, and membranaceous, trilobulate apical one-half deflexed ca. 90°. In contrast with other species of section Decumbentes, in which fruit formation is infrequent, in L.altomayoënsis a high proportion (⁓50-100%) of flowers develop into a fruit; in some flowers the pollinaria rotate and contact the stigma, apparently resulting in at least facultative self-pollination. The main differences among the six species of L.sectionDecumbentes hitherto known are contrasted in a dichotomous key. The new species is known only from three populations located in the Bosque de Protección Alto Mayo, on the Amazonian slope of the Andes in northeastern Peru but appears to be under no foreseeable threats.


ResumenLiparisaltomayoënsissp. nov. es descrita, ilustrada y asignada tentativamente a la sección neotropical Decumbentes con base en sus rizomas postrados, ramificados y tallos ascendentes portando varias hojas. Vegetativamente, la nueva especie se distingue por sus tallos ascendentes cortos con 3­6 hojas, éstas con márgenes undulados, translúcidos y venación reticulada prominente en la superficie superior. Floralmente, es distintivo su labelo con la mitad basal carnosa, provista de una cavidad central redondeada que está limitada a cada lado por una cresta bilobulada prominente y apicalmente por una cresta lunada, y la mitad apical del labelo membranácea, trilobulada y deflexa ca. 90°. En contraste con otras especies de la sección Decumbentes, en las que la producción de frutos es infrecuente, en L.altomayoënsis una alta proporción (⁓50­100%) de las flores produce fruto; en algunas flores los polinarios rotan y contactan el estigma, aparentemente resultando en autopolinización al menos facultativa. Las diferencias principales entre las seis especies de L. sección Decumbentes conocidas hasta ahora se contrastan en una clave dicotómica. La nueva especie se conoce solamente de tres poblaciones localizadas en el Bosque de Protección Alto Mayo, en la vertiente amazónica de los Andes en el noreste de Perú, pero no parece estar sujeta a amenazas previsibles.

16.
PhytoKeys ; 225: 1-40, 2023.
Article in English | MEDLINE | ID: mdl-37252325

ABSTRACT

The Saña River Valley in Northern Peru is unusual for the western slopes of the Peruvian Andes because of its nearly year-round regime of precipitation instead of marked seasonal dry winters. This results in unexpected plant diversity. We surveyed the species of Peperomia (Piperaceae), occurring in this valley from 300 to 3000 m elevation, based on the study of specimens from ten herbaria and field collections, resulting in a total of 81 accessions, of which 48 were made by the authors. We found 16 different taxa: Peperomiacacaophila, from Ecuador, is reported for the first time in Peru; P.cymbifolia, P.dolabriformis and P.emarginulata are reported for the first time for the Saña River Valley; other widely distributed species like P.fraseri, P.galioides, P.haematolepis, P.hispidula, P.inaequalifolia, P.microphylla, and P.rotundata were also found. Five species new to science are described: P.pilocarpa, P.riosaniensis, close to P.palmiformis from Amazonas; P.sagasteguii, related to P.trinervis, P.symmankii, close to P.ricardofernandezii from Piura, and P.vivipara, related to P.alata. A key to the species of Peperomia from the Saña River Valley, based on vegetative characters, is provided.


ResumenEl valle del Río Saña en el norte de Perú es inusual para las vertientes occidentales de los Andes peruanos por su régimen de precipitación ininterrumpido en lugar de inviernos secos estacionales marcados. Esto resulta en una diversidad de plantas inesperada. Revisamos las especies de Peperomia (Piperaceae), del valle del Río Saña entre los 300 a 3000 m de altitud, basándonos en el estudio de especímenes de diez herbarios y colecciones de campo, resultando en un total de 81 accesiones, de las cuales 48 fueron realizadas por los autores. Encontramos 16 taxones diferentes: Peperomiacacaophila, de Ecuador, se reporta por primera vez en Perú; P.cymbifolia, P.dolabriformis y P.emarginulata se reportan por primera vez para el valle del Río Saña; otras especies ampliamente distribuidas como P.fraseri, P.galioides, P.haematolepis, P.hispidula, P.inaequalifolia, P.microphylla y P.rotundata también se encontraron. Se describen cinco especies nuevas para la ciencia: P.pilocarpa, P.riosaniensis, cercana de P.palmiformis de Amazonas; P.sagasteguii, relacionada con P.trinervis, P.symmankii, cercana a P.ricardofernandezii de Piura, y P.vivipara, relacionada con P.alata. Se presenta una clave para las especies de Peperomia del Valle del Río Saña basada en caracteres vegetativos.

17.
Chem Biodivers ; 20(6): e202300274, 2023 Jun.
Article in English | MEDLINE | ID: mdl-37167583

ABSTRACT

The antifungal and insecticidal activities of 34 extracts from 27 plant species were evaluated against fungal phytopathogens of the genus Fusarium and Xyleborus Scolytine ambrosia beetles involved in Fusarium dieback (FD) and laurel wilt (LW) diseases. Sixteen extracts caused mycelial growth inhibition (MGI) above 23 % at 2 mg mL-1 against F. solani, those from S. nudum and M. argyrophylla exhibited the highest MGI (57 % and 49 %, respectively). Thirteen extracts displayed significant antifungal activity against F. kuroshium, those from C. nocturnum and M. argyrophylla exhibited the highest MGI (100 % and 54.9 %, respectively). Additionally, ten plants extracts caused mortality in at least one of the beetle species tested, mainly from Solanaceae species. In the most active species, 39 phenolics were identified that may have contributed to their biological effects. This study is one of the first to report the potential of plant-derived natural products against the causative agents of FD and LW.


Subject(s)
Fusarium , Insecticides , Persea , Animals , Insecticides/pharmacology , Antifungal Agents/pharmacology , Ambrosia , Mexico , Plant Diseases/microbiology , Forests , Plant Extracts/pharmacology
18.
PhytoKeys ; 218: 69-78, 2023.
Article in English | MEDLINE | ID: mdl-36762272

ABSTRACT

Licariaramiroi, a species endemic to western Mexico, is described and illustrated. The ascription of the new species to Licaria is analysed. It is classified in the subgen. Licaria and is most closely related to L.triandra and L.siphonantha from which it differs by its glabrous vegetative and floral structures, stamens mainly with free anthers and the inner wall of the receptacle sericeous. According to the IUCN criteria, the species is classified as critically endangered.

19.
Ecology ; 104(5): e4012, 2023 05.
Article in English | MEDLINE | ID: mdl-36851834

ABSTRACT

The potential effects of climate change on plant reproductive phenology include asynchronies with pollinators and reductions in plant fitness, leading to extinction and loss of ecosystem function. In particular, plant phenology is sensitive to extreme weather events, which are occurring with increasing severity and frequency in recent decades and are linked to anthropogenic climate change and shifts in atmospheric circulation. For 15 plant species in a Venezuelan cloud forest, we documented dramatic changes in monthly flower and fruit community composition over a 35-year time series, from 1983 to 2017, and these changes were linked directly to higher temperatures, lower precipitation, and decreased soil water availability. The patterns documented here do not mirror trends in temperate zones but corroborate results from the Asian tropics. More intense droughts are predicted to occur in the region, which will cause dramatic changes in flower and fruit availability.


Subject(s)
Droughts , Ecosystem , Venezuela , Forests , Plants , Climate Change , Seasons
20.
Am J Bot ; 110(3): 1-11, 2023 03.
Article in English | MEDLINE | ID: mdl-36794648

ABSTRACT

Biogeographic disjunction patterns, where multiple taxa are shared between isolated geographic areas, represent excellent systems for investigating the historical assembly of modern biotas and fundamental biological processes such as speciation, diversification, niche evolution, and evolutionary responses to climate change. Studies on plant genera disjunct across the northern hemisphere, particularly between eastern North America (ENA) and eastern Asia (EAS), have yielded tremendous insight on the geologic history and assembly of rich temperate floras. However, one of the most prevalent disjunction patterns involving ENA forests has been largely overlooked: that of taxa disjunct between ENA and cloud forests of Mesoamerica (MAM), with examples including Acer saccharum, Liquidambar styraciflua, Cercis canadensis, Fagus grandifolia, and Epifagus virginiana. Despite the remarkable nature of this disjunction pattern, which has been recognized for over 75 years, there have been few recent efforts to empirically examine its evolutionary and ecological origins. Here I synthesize previous systematic, paleobotanical, phylogenetic, and phylogeographic studies to establish what is known about this disjunction pattern to provide a roadmap for future research. I argue that this disjunction pattern, and the evolution and fossil record of the Mexican flora more broadly, represents a key missing piece in the broader puzzle of northern hemisphere biogeography. I also suggest that the ENA-MAM disjunction represents an excellent system for examining fundamental questions about how traits and life history strategies mediate plant evolutionary responses to climate change and for predicting how broadleaf temperate forests will respond to the ongoing climatic pressures of the Anthropocene.


Subject(s)
Plants , Phylogeny , Phylogeography , Asia, Eastern , Mexico
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