Julian Alfred Steyermark

Antecedentes y Objetivos: El Libellus de Medicinalibus Indorum Herbis (Librito de las Hierbas Medicinales de los Indios) incluye 185 plantas bellamente ilustradas, 131 interpretadas a especie. Solo algunas se han investigado respecto a las propiedades que ahí se les atribuyen. Por ello, seleccionamos seis plantas utilizadas como antiinflamatorias. Los objetivos de este trabajo fueron corroborar su identidad botánica y determinar si la información química y farmacológica contemporánea respalda sus antiguas aplicaciones terapéuticas.Métodos: Para proponer las especies a las cuales posiblemente corresponden las ilustraciones de las plantas elegidas, estas se compararon con especímenes del Herbario MEXU. Se revisó en bases de datos la fitoquímica y actividad antiinflamatoria de dichas especies.Resultados clave: Las seis plantas seleccionadas del códice corresponden a cinco especies, pues consideramos que las plantas tetzmitl (Folium 13r) y texiyotl (Folium 22v) son la misma especie: Sedum dendroideum. Los extractos de las hojas de S. dendroideum han presentado actividad antiinflamatoria en diferentes modelos farmacológicos debido a derivados del flavonoide kaempferol, lo cual respalda sus antiguas aplicaciones médicas para tratar la cara, ojos y boca hinchados. En el Folium 48v se prescriben tzihuac copalli y tlacoecapatli cuando “se hincha la vena pinchada por la flebotomía”. Concordamos en que son Bursera bipinnata y Litsea glaucescens, respectivamente. A la fecha, no se han investigado sus posibles propiedades antiinflamatorias, pero sí las presentan otras especies relacionadas. El Folium 22v recomienda tememetla y tequixquiçacatl para aliviar la boca inflamada. Corroboramos que son Echeveria gibbiflora y Distichlis spicata, respectivamente. Dichas especies no cuentan con estudios químico-farmacológicos.Conclusiones: La revisión bibliográfica sugiere que las propiedades antiinflamatorias atribuidas en el Códice para S. dendroideum tienen sustento químico y farmacológico. La información quimiotaxonómica y farmacológica sugiere que B. bipinnata y L. glaucescens podrían presentarlas y deben investigarse experimentalmente. Estas tres especies aún se emplean como antiinflamatorias en la medicina tradicional contemporánea.

Knowledge of shortfalls could modify the geographic distribution patterns and limit the actions to conserve the biodiversity, even in the taxa best known. In addition, forest fires also could modify those patterns, but the potential effects of both factors have not been tested. Our aim was to analyze the effect of the Linnean and Wallacean shortfalls in the first evaluation of wildfire impacts on 22 amphibian and 13 mammal species distributed in Guanajuato, Mexico. We evaluated those shortfalls using the non-parametric estimator Chao2 and the Qs estimator and through maps of species richness patterns. To evaluate the effects of wildfires, we produced a fire recurrence map and quantified the burned area within species distributions and in 24 Protected Natural Areas (PNA) in the state. The Linnean shortfall showed some species missing to record in Guanajuato for both taxa, while the Wallacean shortfall showed poor quality of knowledge. Fire recurrence was high within 5 PNA. The richness patterns affected by fires covered nearly 17% of the surface of Guanajuato. Improving the knowledge of biogeographical patterns could provide better tools to stakeholders to decrease the negative impact of fires within PNA.

Premise Cleomaceae is an important model clade for studies of evolutionary processes including genome evolution, floral form diversification, and photosynthetic pathway evolution. Diversification and divergence patterns in Cleomaceae remain tangled as research has been restricted by its worldwide distribution, limited genetic sampling and species coverage, and a lack of definitive fossil calibration points.MethodsWe used target sequence capture and the Angiosperms353 probe set to perform a phylogenetic study of Cleomaceae. We estimated divergence times and biogeographic analyses to explore the origin and diversification of the family. Seed morphology across extant taxa was documented with multifocal image‐stacking techniques and morphological characters were extracted, analyzed, and compared to fossil records.ResultsWe recovered a well‐supported and resolved phylogenetic tree of Cleomaceae generic relationships that includes 236 (~86%) species. We identified 11 principal clades and confidently placed Cleomella as sister to the rest of the family. Our analyses suggested that Cleomaceae and Brassicaceae diverged ~56 mya, and Cleomaceae began to diversify ~53 mya in the Palearctic and Africa. Multiple transatlantic disjunct distributions were identified. Seeds were imaged from 218 (~80%) species in the family and compared to all known fossil species.ConclusionsOur results represent the most comprehensive phylogenetic study of Cleomaceae to date. We identified transatlantic disjunctions and proposed explanations for these patterns, most likely either long‐distance dispersals or contractions in latitudinal distributions caused by climate change over geological timescales. We found that seed morphology varied considerably but mostly mirrored generic relationships.

Submerged macrophytes remediation is a commonly used technique for improving water quality and restoring habitat in aquatic ecosystems. However, the drivers of success in the submerged macrophytes assembly process and their specific impacts on methane emissions are poorly understood. Thus, we conducted a mesocosm experiment to test the growth plasticity and carbon fixation of widespread submerged macrophytes (Vallisneria natans) under different nutrient conditions. A refined dynamic chamber method was utilized to concurrently collect and quantify methane emission fluxes arising from ebullition and diffusion processes. Significant correlations were found between methane flux and variations in the physiological activities of V. nantas by the fluorescence imaging system. Our results show that exceeding tolerance thresholds of ammonia in the water significantly interfered with the photosynthetic systems in submerged leaves and the radial oxygen loss in adventitious roots. The recovery process of V. natans accelerated the consumption of dissolved oxygen, leading to increase in the populations of methanogen (153.3 % increase of mcrA genes) and subsequently elevating CH4 emission fluxes (23.7 %) under high nutrient concentrations. Conversely, V. natans increased the available organic carbon under low nutrient conditions by radial oxygen loss, further increasing CH4 emission fluxes (94.7 %). Quantitative genetic and modeling analyses revealed that plant restoration processes drive ecological niche differentiation of methanogenic and methane oxidation microorganisms, affecting methane release fluxes within the restored area. The speciation process of V. natans is incapable of simultaneously meeting improved water purification and reduced methane emissions goals.

The Khanka Lowland forest-steppe is the most eastern outpost of the Eurasian steppe biome. It includes unique grassland plant communities with rare steppe species. These coenosis have changed under the influence of anthropogenic activity, especially during the last 100 years and included both typical steppe species and nemoral mesophytic species. To distinguish these ecological groups of plants the random forest method with three datasets of environmental variables was applied. Specifically, a model of classification with the most important bioindices to predict a mesophytic ecological group of plants with a sensitivity greater than 80% was constructed. The data demonstrated the presence of steppe species that arrived at different times in the Primorye Territory. Most of these species are associated with the Mongolian-Daurian relict steppe complex and habit in the Khanka Lowland. Other species occur only in mountains in Primorye Territory and do not persist in the Khanka Lowland. These findings emphasize the presence of relict steppe communities with a complex of true steppe species in the Khanka Lowland. Steppe communities exhibit features of anthropogenic influence definitely through the long land use period but are not anthropogenic in origin. The most steppe species are located at the eastern border of distribution in the Khanka Lowlands and are valuable in terms of conservation and sources of information about steppe species origin and the emergence of the steppe biome as a whole.

Capim dourado, also known as sedinha, refers to the everlasting flower Syngonanthus nitens (Bong.) Ruhland (Eriocaulaceae), prized for its use in crafting and as a significant income source for communities in Minas Gerais, Bahia, and Tocantins, Brazil. This plant is also utilized in the creation of highly valued jewelry and accessories on the global market. This study aims to ascertain the thermal and humidity thresholds of S. nitens while mapping and predicting its current and future distribution. Initially, distribution data was gathered through a literature review, supplemented by biological temperature and humidity data collected from the Quilombola Raiz Community in Minas Gerais and a germination experiment conducted at the Integrated Multi-User Research Laboratory of the Jequitinhonha and Mucuri Valleys (LIPEMVALE). Climate Index (CLIMEX) parameters were defined using biological information and occurrence locations. The optimal temperature range for S. nitens development is between 18 and 24 °C, with minimum and maximum thresholds of 5 °C and 40 °C respectively. Ninety-two occurrence records were found, all situated in South America, aligning with high climate suitability regions as per the model predictions. Future projections for 2050 and 2100 indicate a decrease in areas suitable for S. nitens. These findings provide crucial insights for decision-making, necessitating measures such as widespread monitoring, collaborative conservation efforts, and the establishment of sustainable use zoning to manage S. nitens effectively.

The shrub, Robinia hispida L., commonly known as the bristly locust, is a native to southeastern United States. It has, however, expanded its range within North America, and established invasive native-alien populations in several American states and Canada. Outside of North America, R. hispida has been introduced to Europe and Asia, where it has naturalised and is considered invasive. Notably, the presence of this shrub has never been reported outside of cultivation in Africa. Despite receiving little scientific attention compared to its congeneric species such as the global invader Robinia pseudoacacia L., R. hispida shares morphological and growth characteristics including rapid growth and a suckering habit. It occupies similar environmental niches in both native and introduced ranges, thriving in thin upland woodlands, woodland edges, thickets, fence rows, roadside embankments, banks of drainage canals, vacant lots, and overgrown waste areas. In South Africa, R. hispida was first recorded in a garden in Polokwane in 1986, while the first record outside of cultivation was near the town of Bethlehem in the Free State Province in 2023, and further surveys were conducted locating additional populations near the towns of Zastron and Clarens in 2024. The potential distribution of R. hispida in South Africa was modelled in MaxEnt using areas climatically representative of the species, based on the Koppen-Geiger climate classifications. The potential distribution includes areas of central South Africa, the east and south coast and the Mediterranean climates of the southern Cape. Management strategies suggested for R. hispida in South Africa, considering the small size of the populations, should include eradication efforts using mechanical and chemical means, followed by continuous monitoring to prevent re-emergence.

It would be advantageous to grow legume forage crops in order to increase the productivity and sustainability of sloped croplands in Hamkyongbukdo. In particular, the identification of potential cultivation areas for alfalfa in the given region could aid decision-making on policies and management related to forage crop production in the future. This study aimed to analyze the climate suitability of alfalfa in Hamkyongbukdo under current and future climate conditions using the Fuzzy Union model. The climate suitability predicted by the Fuzzy Union model was compared with the actual alfalfa cultivation area in the northern United States. Climate data obtained from 11 global climate models were used as input data for calculation of climate suitability in the study region to examine the uncertainty of projections under future climate conditions. The area where the climate suitability index was greater than a threshold value (22.6) explained about 44% of the variation in actual alfalfa cultivation areas by state in the northern United States. The climatic suitability of alfalfa was projected to decrease in most areas of Hamkyongbukdo under future climate scenarios. The climatic suitability in Onseong and Gyeongwon County was analyzed to be over 88 in the current climate conditions. However, it was projected to decrease by about 66% in the given areas by the 2090s. Our study illustrated that the impact of climate change on suitable cultivation areas was highly variable when different climate data were used as inputs to the Fuzzy Union model. Still, the ensemble of the climate suitability projections for alfalfa was projected to decrease considerably due to summer depression in Hamkyongbukdo. It would be advantageous to predict suitable cultivation areas by adding soil conditions or to predict the climate suitability of other leguminous crops such as hairy vetch, which merits further studies.

Coniferous forests are under severe threat of the rapid anthropogenic climate warming. Abies (firs), the fourth‐largest conifer genus, is a keystone component of the boreal and temperate dark‐coniferous forests and harbors a remarkably large number of relict taxa. However, the uncertainty of the phylogenetic and biogeographic history of Abies significantly impedes our prediction of future dynamics and efficient conservation of firs. In this study, using 1,533 nuclear genes generated from transcriptome sequencing and a complete sampling of all widely recognized species, we have successfully reconstructed a robust phylogeny of global firs, in which four clades are strongly supported and all intersectional relationships are resolved, although phylogenetic discordance caused mainly by incomplete lineage sorting and hybridization was detected. Molecular dating and ancestral area reconstruction suggest a Northern Hemisphere high‐latitude origin of Abies during the Late Cretaceous, but all extant firs diversified during the Miocene to the Pleistocene, and multiple continental and intercontinental dispersals took place in response to the late Neogene climate cooling and orogenic movements. Notably, four critically endangered firs endemic to subtropical mountains of China, including A. beshanzuensis, A. ziyuanensis, A. fanjingshanensis and A. yuanbaoshanensis from east to west, have different origins and evolutionary histories. Moreover, three hotspots of species richness, including western North America, central Japan, and the Hengduan Mountains, were identified in Abies. Elevation and precipitation, particularly precipitation of the coldest quarter, are the most significant environmental factors driving the global distribution pattern of fir species diversity. Some morphological traits are evolutionarily constrained, and those linked to elevational variation (e.g., purple cone) and cold resistance (e.g., pubescent branch and resinous bud) may have contributed to the diversification of global firs. Our study sheds new light on the spatiotemporal evolution of global firs, which will be of great help to forest management and species conservation in a warming world.

Understanding the extent to which climate limitations drive elevation stratification among species is integral to predicting the impacts of climate change. Zonation patterns of species within mountains have been well documented, and shifts in these patterns have been correlated with recent warming. However, the physiological mechanisms that explain these zonation patterns are not well understood. We used a system of broadly sympatric oak species within semi‐arid mountains to (1) investigate the extent to which species elevation ranges correlate with climate, (2) test for associations of cold and drought resistances with upper and lower elevation limits, and for trade‐offs between resistance mechanisms with elevation, and (3) examine the extent to which species‐wide climatic ranges predict traits that drive local community assembly along an elevation gradient. We found that aridity gradients but not winter minimum temperatures predict oak stratification. Species differed in drought resistance, demonstrating a trade‐off between drought avoidance and drought recovery. At lower elevations, species avoided drought stress during the dry season through leaf abscission; at upper elevations, they maintained transpiration but recovered from daily desiccation via higher leaf water storage capacity, rather than tolerating desiccation via lower turgor loss points. Freezing resistance, measured as stem electrolyte leakage, was not correlated with elevation differences. Taken together, these results indicate that elevation stratification is linked to drought resistance rather than freezing resistance. We also found evidence of niche partitioning among closely related oaks linked to contrasting leaf phenology. The functional, phenological, and physiological traits important for elevation stratification were correlated with species’ range‐wide mean annual precipitation and precipitation seasonality, but not aridity. Our findings indicate that drought resistance along a leaf avoidance–recovery trade‐off is integral to species stratification within this semi‐arid montane system. Additionally, the mechanism of stratification acts upon traits and strategies conserved at the species level. Species within this system are likely vulnerable to range retraction under increased drought as a consequence of this phenological avoidance–physiological tolerance trade‐off.