Folia Geobotanica

Gxasheka, Masibonge; Dlamini, Phesheya

doi: 10.1007/s12224-025-09469-wpmid: N/A

The encroachment of shrub species into mountainous grasslands threatens global biodiversity and ecosystem stability. Shrub encroachment is influenced not only by the environmental characteristics of the region, but also by specific traits of the encroaching shrub species, such as leaf nutrient concentration. However, the topography-driven changes in the leaf nutrient concentration of encroaching shrub species in mountainous grasslands remain largely unexplored. Here we examined how landscape topography and selected soil edaphic properties influence the leaf nutrient composition of the encroaching shrub Euryops floribundus N.E. Br in three mountainous grassland sites in eastern South Africa. Each landscape site was surveyed and demarcated into three topographic positions: downslope, midslope, and upslope. In each topographic position per site, six 10 m x 10 m plots were randomly selected to collect leaf samples from Euryops floribundus, along with soil samples taken from the topsoil layer. We found evidence that landscape topography, nutrient availability and associated chemistry of the soil influences leaf nutrient concentrations of the encroaching Euryops floribundus. Specifically, leaf phosphorus concentration in the downslope position was 33% higher compared to upslope position in Manzimdaka, and correlated to effective cation exchange capacity, exchangeable acidity and acid saturation of the soil. Leaf potassium concentration increased by 22% in downslope positions compared to upslope positions in Tsengiwe. A similar trend of leaf potassium content was observed in Manzimdaka, although a significant increase of 20% occurred between downslope compared to midslope positions. We also observed a 37% and 28% increase in leaf zinc concentration in downslope positions compared to upslope positions in Tsengiwe and Manzimdaka, respectively. Furthermore, leaf manganese was 63% lower in downslope positions compared to upslope positions in Upper Mnxe. This study provides valuable insights into the impact of landscape topography on the nutrient concentration of encroaching shrub species in mountainous grasslands. The examination of leaf nutrient traits along a topographic gradient will lead to improved understanding of plant strategies at local scales and give much needed insights into the ecological mechanisms that influence the dominance and persistence of Euryops floribundus monoculture stands in mountainous grasslands.

Nakamura, Shunya; Torimaru, Takeshi; Ao, Hinako; Akaji, Yasuaki; Akada, Shinji; Kisanuki, Hiromitsu

doi: 10.1007/s12224-025-09471-2pmid: N/A

Prolonged drought stress at mild/moderate intensities is assumed to be a realistic situation that natural tree populations will face in the future warming climate. Here we performed a six-week experiment during which water supplies were controlled by applying a repeated cycle of intermittent watering to the current-year seedlings of Fagus crenata originating from two snowy regions in Japan, in order to examine the effects of moderate, prolonged, but gradual, soil drought stress on them as well as to determine any site-common and/or -specific patterns. Compared to the well-watered seedlings, there were no or limited changes in stomatal conductance, leaf water content, root-to-shoot ratio, and concentrations of total soluble sugar and free-proline in leaves of the seedlings that received intermittent watering over the three census dates. In contrast, the seedlings from both sites that received intermittent watering exhibited significant increases in the concentration of malondialdehyde in leaves on every census date, compared to well-watered seedlings. There were very few notable between-site differences in any of the phenotypic traits mentioned above. Due to the moderate intensity of drought stress combined with unexpectedly high vapor pressure deficit and low light intensity in the greenhouse, we detected neither drought stress-driven stomatal closure nor cellular osmotic balancing; however, reactive oxygen species may have been produced in leaves of the seedlings. These findings imply that the concentration of malondialdehyde is a promising candidate biochemical marker for detecting early signs of adverse effects on F. crenata seedlings under soil drought conditions in the future warming climate.

Sahli, Abdelouahab; Ennouni, Hassan; Chakkour, Soufian; Kadaoui, Khalil; Houssni, Mhammad; Ater, Mohammed

doi: 10.1007/s12224-025-09472-1pmid: N/A

Moroccan populations of Alnus glutinosa represent a climatic relic. These populations are isolated and threatened by both climate change and human activities. Using leaves from twelve populations of A. glutinosa, this study reveals intraspecific variation in leaf traits and explores how these traits respond to climatic, geographical and hydrological factors. Descriptive statistical analysis and nested analysis of variance revealed significant differences in 22 leaf traits of A. glutinosa, both among and within populations, with a broad range of coefficients of variance (10% to 52.8%), and the majority of leaf phenotypic variation was observed within individual trees. Principal component analysis revealed that the cumulative contribution of the top three principal components largely explained the phenotypic variation of A. glutinosa leaves (74.85%). Linear mixed- effect models indicated a slight effect of climatic factors and a significant effect of hydrological factors on leaf traits. Linear mixed-effect models revealed that the leaf traits of A. glutinosa are mainly affected by channel width, distance to the channel edge, and height above the water level. In addition, a strong relationship between leaf shape traits and elevation was observed, with leaves becoming narrower with increasing elevation. These results contribute to a better understanding of the leaf morphological traits of A. glutinosa and the extent to which the environment influences leaf trait variation. They may provide a scientific basis for the conservation of A. glutinosa.

Dudáš, Matej; Ghendov, Veaceslav; Ioniţa, Olga; Mártonfiová, Lenka

doi: 10.1007/s12224-025-09470-3pmid: N/A

A revision of the Taraxacum section Erythrosperma in the Republic of Moldova, based on fieldwork and the study of herbarium specimens, has revealed two new species, T. parnassicum and T. persicum, for the country’s flora, confirmation of the occurrence of the sexually reproducing species T. erythrospermum s. str., and records of plants belonging to the T. scanicum group, previously never reliably documented in the Republic of Moldova. These findings are supplemented or supported by descriptions of the species and their distribution, photographs of herbarium specimens, and chromosome numbers and ploidy information. The chromosome number of T. persicum, 2n = 24, is reported here for the first time. An identification key to T. sect. Erythrosperma in Republic of Moldova, compiled based on the newly collected material, is presented.

Damayanto, I Putu Gede P.; Rugayah, ; Sulistiarini, Diah; Sunarti, Siti; Astuti, Inggit Puji; Primananda, Enggal

doi: 10.1007/s12224-025-09473-0pmid: N/A

Research on Dracaena (Asparagaceae) in Asia has been relatively limited in recent decades. Numerous taxonomic and nomenclatural issues remain unresolved. In Indonesia, the species diversity of Dracaena remains uncertain. To address this, field explorations have been conducted on several Indonesian islands, including Sulawesi, where several Dracaena specimens of unclear taxonomic status were discovered. Herbarium specimens collected from Sulawesi have been examined, and in addition to the macromorphological characters, micromorphological observations using scanning electron microscopy (SEM) were also carried out. A global conservation status assessment was conducted for all species based on IUCN criteria. Three species of Dracaena were documented from Sulawesi: D. angustifolia, D. banggaensis, and D. multiflora. Dracaena banggaensis is newly proposed and described as a distinct species in this study. It is closely related to widespread southeast-Asian D. elliptica in terms of inflorescence type but differs in leaf and flower characteristics. The micromorphology of Dracaena species showed many similarities among the species, but D. banggaensis was distinguished by its raphide crystals and rough seed coat. According to the IUCN criteria, D. angustifolia and D. multiflora is classified as Least Concern (LC), while D. banggaensis is assessed as Critically Endangered (CR). A description, identification key, and illustrations of these species is provided.