Ecological Research最新文献

Nickel is a crucial metal widely used in various industrial applications, such as lithium-ion batteries and stainless-steel production. The increasing demand for nickel and resource depletion challenges highlight the need for sustainable extraction methods. Agromining employs hyperaccumulator plants to extract nickel from soils that are either contaminated or naturally enriched in nickel. Bornmuellera emarginata is a nickel hyperaccumulator originating from Greece and a promising candidate for nickel agromining. This study aimed to identify suitable genotypes for a successful “domestication” breeding program, focusing on phenotypic traits. Seeds from 35 plants across six wild populations were cultivated under controlled conditions for 7 months to complete a full life cycle. In this period, growth parameters (e.g., plant height (PH), leaf size, and biomass) were determined. Geographically proximate populations displayed greater phenotypic similarity than those from distant locations. Substantial morphological variations, including PH (40–126 cm) and leaf length (6–13 cm), were observed. Nickel concentrations in plants ranged from 290 to 6250 mg kg⁻¹ dry weight, resulting in nickel yields of 10–145 mg/plant. The notable phenotypic differences among genotypes provide a valuable biological resource for initiating a breeding program to enhance overall nickel yield in B. emarginata agromining crops. Selection and breeding efforts should prioritize genotypes with high biomass production and nickel concentrations. This research lays the foundation for targeted breeding to optimize the potential of B. emarginata in nickel agromining.

Despite recent efforts to make large-scale biodiversity datasets available, several data shortfalls still exist that preclude our progress in achieving global conservation and sustainability goals. In this study, we present a comprehensive native tree dataset (1689 species) from the Indian Himalayan Region (IHR)—home to two global biodiversity hotspots—assembled from an extensive data synthesis. Based on this database, we investigate the geographic patterns and drivers of α- and β-taxonomic and phylogenetic diversity of the native trees among 13 different provinces of IHR. Our results revealed a considerable variation in the α- and β-taxonomic and phylogenetic diversity among the provinces of IHR, with the highest values in eastern provinces. We found phylogenetic clustering mostly in the western provinces, and phylogenetic dispersion in the eastern provinces. We found a positive correlation between the taxonomic and phylogenetic dissimilarity across the IHR. Also, the different sets of explanatory variables explained the variation of tree species richness, standardized effect size of phylogenetic diversity, net relatedness index, and nearest taxon index, with maximum contribution by temperature seasonality (Bio4). Furthermore, temperature-related climatic distance individually explained most of the variation in the taxonomic and phylogenetic dissimilarity between the provinces of IHR. Overall, our findings unveil the patterns of taxonomic, biogeographic, and phylogenetic dimensions of tree flora in the IHR, which in turn can help in formulating scientific data-based regional policy and conservation strategies. Looking forward, we presented a model study for bridging the Linnean, Wallacean, and Darwinian shortfalls in the globally data-deficient biodiversity-rich regions.

In drylands, grass germination occurs after a large rainfall event. However, trees influence the water requirements for germination either by decreasing the rate of evaporation from soil surface or by interception rainfall with their canopy. The aim of this work was to evaluate the role of Neltuma flexuosa tree on the germination of Leptochloa crinita and Pappophorum caespitosum grasses in response to precipitation events of different sizes. The experiment was conducted in two locations within the Monte desert, Argentina: a semi-arid location with an average annual precipitation of 345 mm and an arid location with an average annual precipitation of 156 mm. Six microsites were established under N. flexuosa canopies and six microsites in open areas at both locations. Within each microsite, 35 seeds of each grass species were exposed to precipitation events of varying sizes. This procedure was repeated 14 times across two growing seasons. Germinated seeds were counted in the laboratory. Generalized linear mixed models were then applied to evaluate the effects of accumulated precipitation and the microsite on the grass germination in both locations. Results showed that N. flexuosa did not influence the germination of either grass species in the arid location. However, in the semi-arid location, N. flexuosa facilitated the germination of P. caespitosum only. Large precipitation events would act as an environmental signal for these perennial grasses, allowing them to germinate in favorable years regardless of the microsite or the location.

Hyperaccumulators are unusual plants that accumulate specific metals or metalloids in their living tissues to concentrations that may be hundreds or thousands of times greater than those normal for most plants. Hyperaccumulator plants are of practical importance as they can be used in soil remediation technologies. The Shebenik Mountain massif, located on the eastern border of Albania, hosts a wide diversity of rare and endemic plant species, including nickel hyperaccumulators. The aim of this study was to evaluate the taxa present on the Shebenik Mt. in relation to soil conditions and to test their potential for phytomining in a replicated field trial. Previous morphological and karyological analyses of material from field collections across ultramafic outcrops of the Shebenik resulted in the identification of the following nickel hyperaccumulator taxa: Odontarrhena chalcidica (Janka) Španiel & al., Odontarrhena smolikana subsp. glabra (Nyár.) Španiel & al., Odontarrhena rigida (Nyár.) L. Cecchi & Selvi, and Bornmuellera baldaccii (Degen) Heywood. In addition, a species of the genus Noccaea, formerly referred to Noccaea ochroleuca (Boiss. & Heldr.) F.K. Mey, but likely belonging to a still undescribed taxon, was also collected. An in situ replicated trial was undertaken to evaluate the potential for phytomining of three nickel (Ni) hyperaccumulators collected in the Shebenik Mt. Measurement of aboveground biomass, analysis of nickel in the biomass, and analyses of plant-available nickel in the soil allowed calculation of bioaccumulation and phytoextraction yield. This provides a realistic evaluation of the efficacy of the plant taxa in hyperaccumulating nickel and their potential use for phytoextraction/phytomining technologies.

Intraspecific communication among carnivores can be complex and risky, and many solitary carnivores (including pumas; Puma concolor) primarily communicate with potential mates and competitors indirectly via scent marking at communication hubs. We used multiple temporal analyses to understand if pumas of three classes (males, solo females, and females traveling with dependent kittens) varied in their temporal use of communication hubs to reduce risk while gathering information. We hypothesized that males would visit scrapes at typical times (nighttime), but that female behavioral strategies might vary based on whether they had dependent kittens or not. We found that pumas of different classes varied in their temporal patterns: male pumas concentrated their temporal activity at night (which is typical for pumas), solo females also tended to visit during the nighttime (although slightly earlier on average than males), while females with kittens were more active in the daytime. Our findings highlight the importance of communication hubs for intersexual communication in pumas and the flexibility that is inherent in puma behavioral ecology. Females adjusted their temporal behavior and visitation based on their reproductive status and life history stage, likely to assess dominant territorial males while also limiting their risk. Our study provides a mechanistic view of how communication through scent marking allows both long-term and spatially separated communication to occur and that may allow pumas at different life stages with different risk tolerances to communicate with each other.

Bamboo flowering occurs over a long cycle, yet the precise mechanisms and consequences of this phenomenon remain unknown. Although several studies have investigated the dynamics of forest communities post-flowering, the effects of flowering on the material cycle remain unclear. Recent reports have documented the first flowering of Phyllostachys nigra var. henonis in 120 years across several regions of Japan. P. nigra var. henonis flowers exhibit higher nitrogen concentrations compared to their leaves, suggesting potentially different decomposition patterns upon reaching the forest floor and subsequent contributions to the nitrogen cycle. Based on this observation, we conducted decomposition experiments using litter bags to investigate the dynamics of organic matter and nitrogen. After 1 year, litter bags containing both leaves and flowers were retrieved. The remaining mass of flower and leaf litter was 38% and 60%, respectively. On the other hand, the nitrogen remaining in flower and leaf litter was 54.9% and 98.2%, respectively. Net nitrogen release from the flower litter was estimated to be 36 kg/ha/year in the study site. The potential maximum nitrogen released from flower litter decomposition in a high-density ramet stand was estimated to be 221 kg/ha/year. The results of this study suggest that the nitrogen addition through mass flowering of P. nigra var. henonis would have a significant impact on the nitrogen cycle of the ecosystem.