Ecological Requirements Research Articles

Genetics and Distribution of the Italian Endemic Campanula fragilis Cirillo (Campanulaceae)

Campanula fragilis Cirillo is a species distributed in central and southern Italy and includes two subspecies with uncertain taxonomic position and distribution. By means of nuclear and chloroplast markers, we attempted at testing the genetic distinctness of the two subspecies, as well as their possible correspondence with geographical or ecological patterns. After a revision of geographic occurrences based on herbarium data, we carried out species distribution modeling to assess the present and future distribution of this species under different ecological variables, also for conservation purposes. Our findings support the recognition of two weakly differentiated taxa, here accepted at subspecific rank, in agreement with the current taxonomic treatment. We found that C. fragilis subsp. cavolinii is monophyletic and limited to mountains and hills of central Italy. On the contrary, C. fragilis subsp. fragilis shows a higher genetic variability and a broader distribution in central and southern Italy, with a wider altitudinal range from coasts to mountain cliffs. We confirmed that both subspecies are narrowly calcicolous and have similar ecological requirements, but C. fragilis subsp. cavolinii occurs in colder habitats. Our results forecast a significant distribution contraction in the long term.

Physicochemically modified polymer-based fluidic gates with tunable wetting properties for intelligent liquid manipulations

The creation of a selective flow path and the regulation of a flow rate are of critical importance for polymer-based devices that manipulate liquid at the microscale. The formation of a 3D interconnected network of voids (i.e., physical volumetric modification) and the addition of a nonionic surfactant, Silwet L-77, (i.e., chemical volumetric modification) are expected to affect the wetting properties of polymers, thereby achieving selective gating effect in the polymer-based devices as an appropriate technology. Here, a set of polydimethylsiloxane (PDMS)-based fluidic gates (F-gates) were developed to enable selectivity for liquids and flow-rate control of the liquids by tuning the wetting properties of PDMS with the physicochemical volumetric modifications. For water and oil with different surface tensions (STs), the effects of the physical and chemical volumetric modifications on the fluidic gating of PDMS were quantitatively characterized in terms of contact angle, mass flow rate, and liquid absorption speed. The applicability of PDMS-based F-gates to the selective separation of oil and water even from oil-in-water emulsion was demonstrated by fabricating Janus PDMS-based F-gates. Our physicochemical volumetric modifications were also extensively analyzed to examine whether they satisfy the technological, economic, and ecological requirements of appropriate technology. This is the first effort to tailor the wetting properties of PDMS through physicochemical volumetric modifications, thus configuring a set of PDMS-based F-gates that act both as a separator for liquids of different STs and as a switch for fluid flows.

Integrating external stressors in supervised machine learning algorithm achieves high accuracy to predict multi-species biological integrity index of aquaculture wastewater

Monitoring and predicting the environmental impact of wastewater is essential for sustainable aquaculture. The environmental DNA metabarcoding-integrated supervised machine learning (SML) algorithm is an alternative method for ecological quality assessment and prediction. However, the ecological integrity of aquaculture wastewater and available effective input features for prediction remain unclear. Here, we used the multispecies biological integrity index (Ms-IBI) to provide a detailed categorization, identifying over half of the samples (53.85 %) as highly impacted, emphasizing the urgency to address ecological degradation; Ms-IBI emerged as a reliable label for SML models. By condensing 410 effective indicators and integrating 25 core operational taxonomic unit features with external stressors, an accuracy of 0.78 and R2 of 0.96 was achieved. Utilizing only external stressors yielded a comparably good performance with fewer input features, obtaining an accuracy of 0.74 and an R2 of 0.91. The integration of external stressors in this study highlights a practical predictive method that meets the ecological quality requirements of aquaculture wastewater, aiding the reversal of global ecological decline.

A multi-index comprehensive evaluation method for assessing the water use balance between economic society and ecology considering efficiency-development-health-harmony.

Quantitative assessment of the water use balance between economic society and ecology (EEWB) is the basis for coordinating the competitive relationship of water use between human activity and ecological requirements and. It is of great significance for optimizing the water resources carrying capacity and achieving a healthy regional water balance. Based on the concept of harmonious balance, this paper puts forward the definition and connotation of EEWB regarding the competition in water use between economic society and ecology. And, a novel framework for assessing the EEWB is proposed. It has four aspects relating to water resources, economic society, ecology, and human-water relationship. Linked to these aspects the Data Envelopment Analysis (DEA) technique, Water Ecological Footprint (WEF) model, InVEST model and indicators system of human-water relationship are used to establish a water resources efficiency index (IEEWB-W), economic society high-quality development index (IEEWB-ES), ecology health index (IEEWB-E), harmony index of human-water relationship (IEEWB-H). The four indices were then integrated into the water use balance between economic society and ecology index (IEEWB) with Euclidean distance, thus forming the EEWB quantification method system. Finally, the temporal and spatial characteristics of EEWB during 2010-2022 was diagnosed in Henan Province and cities of China. Results reveal that: (1) The water resources utilization efficiency exhibit a changing trend of initial decrease followed by subsequent increase; (2) Southern cities in Henan Province have a higher economic society development level compared to northern cities; (3) IEEWB-E in Henan Province is below 0.60, indicating that the regional ecology health remains consistently vulnerable; (4) IEEWB-H in Henan Province shows an increasing trend, indicating that a gradual improvement and overall upward development in the human-water relationship; (5) IEEWB multi-year average was within [0.53, 0.65] in Henan Province, indicating a state of Proximity imbalance. The low level of ecological health is the primary influencing factor. These findings will contribute to a better understanding of the water use balance between economic society and ecology and provide scientific reference for achieving a healthy regional water balance.

Maastrichtian palaeoenvironments and palaeoclimate reconstruction in southern South America (Patagonia, Argentina) based on fossil fungi and algae using open data resources

ABSTRACT The use of non-pollen palynomorphs (NPP), particularly fossil fungi and algae, as palaeobiological proxies for Late Cretaceous palaeoenvironmental and palaeoclimatic reconstructions of warm-to-hot greenhouse conditions, can enhance our understanding of climate change impacts on modern Patagonian environments. This study aimed to reconstruct the Maastrichtian palaeoenvironment and palaeoclimate in the Cañadón Asfalto Basin (CAB, Chubut Province) by testing these NPPs as proxies using the Nearest Living Relative method (NLR). Moreover, using modern ecological requirements from open-source databases, such as GBIF and processing it with an open-source, cross-platform tool like QGIS, linked with Köppen-Geiger shapefiles, provided evidence of climate-driven palaeo-distribution patterns of fungal and algal diversity at CAB. Applying modern ecological requirements and biogeographic distribution data, we reconstructed the palaeoclimate as temperate with evenly distributed precipitation and warm summers, corresponding to the Cfb climate zone in Köppen-Geiger classifications. Additionally, our methodology produced reliable results regarding Cenozoic floras’ physiognomies based on fossil fungi, revealing a transition from sparsely wooded areas with palms and prairies to complex forest ecosystems with palms, deciduous trees, and shrubland. Furthermore, testing Cretaceous algae with the NLR method, for the first time, provided comprehensive insights into past water body characteristics, including trophic state and water quality.

Characterization of Enterobacter cloacae CAUCoF_BF_01: an autochthonous heterotrophic nitrifying strain from culture ponds for biofloc applications

The biofloc environment needs specific heterotrophic nitrifying bacteria for optimal system performance, hence screening perfect bacterial strains is crucial. Enterobacter cloacae sp. was identified as a novel heterotrophic bacterium isolated from freshwater pond sediment during July, 2022. Through high-throughput sequencing, the isolated bacterium was identified as E. cloacae CAUCoF_BF_01, which demonstrated potential nitrogen removal via heterotrophic nitrification and aerobic denitrification, as well as a preference for different C/N ratios (C/N10, 15, 20, and 25) for consuming nitrogen sources. The bacteria performed superior (p < 0.05) ammonia-N and nitrite-N removal in C/N20, with efficiencies of 91.70% and 91.0%, respectively. C/N15, on the other hand, had higher nitrate-N removal efficiency (69.20%). Furthermore, the optimum temperature for the chosen strain was determined to be 30 °C. This strain, on the other hand, can thrive in temperatures ranging from 20 to 37 °C and pH levels ranging from 6 to 10. Furthermore, the biofilm test reveals that the selected bacterial strain has the potential to form biofilm via extracellular polymeric compound secretion, besides passing ecological safety requirement. The current investigation will be helpful in the development of a successful biofloc-based probiotic for managing system generated ammonia to an optimal level, as well as floc production to maximize system efficiency.

Chilgoza Pine: A Comprehensive Review on Ecology, Cultivation, and Economic Potential of an Underutilized Nut Crop

Chilgoza pine (Pinus gerardiana L.) is an underutilized nut crop native to the high-altitude regions of South Asia, particularly the western Himalayas. This comprehensive review aims to provide an in-depth understanding of Chilgoza pine's ecology, cultivation practices, and economic potential. The review synthesizes current knowledge on the tree’s ecological requirements, including its adaptation to arid and mountainous environments. It examines cultivation techniques, challenges faced in agronomic practices, and recent advancements in improving yield and quality. Additionally, the economic potential of Chilgoza pine is explored, highlighting its role in local economies, market trends, and opportunities for commercialization. This review underscores the significance of Chilgoza pine in sustainable agriculture and its potential as a high-value nut crop.

Home range sizes and nychthemeral habitat uses by the Northern Shoveler (Spatula clypeata) on prenuptial stopovers in Vendée marshes, western France

The wetlands of Marais breton (MB) and Marais poitevin (MP) on the French Atlantic coast are commonly used by several duck species, especially as stopover sites during the prenuptial migration. Understanding the ecological requirements of Anatidae at spring stopover sites is important to define appropriate management actions that might have a carry over effect on the subsequent reproduction success. This study focused on the Northern Shoveler (Spatula clypeata), a species that regularly visits the two marshes during spring and fall migrations and is highly dependent on freshwater invertebrates as the food resource. Fifteen Northern Shovelers were equipped with GPS/GSM tags and monitored during their stopover in both marshes in 2020 and 2021. The aims of the study were to understand the habitat use on stopover sites and relate home range (HR) size with characteristics of the feeding habitats (such as freshwater invertebrates’ density and diversity). The HR area of the studied individuals was mainly constituted of ponds in MB (83% of the HR) and wet meadows in MP (71% of the HR). The Northern Shovelers equipped with tag spent more than 72 consecutive hours in 31 wetlands, using them during the day, at night or all day. The diurnal visited sites were deep ponds that were sparsely vegetated and dominated by microcrustaceans, whereas the nocturnal visited sites were wet meadows or ponds with high aquatic vegetation cover and high invertebrate taxonomic diversity. The 31 described sites appeared to be rich in freshwater invertebrates, with no significant difference in invertebrate densities between the diurnal and nocturnal sites. HR sizes were highly homogenous between the two study sites (MB and MP), between sexes or between age classes. In conclusion, according to this study, an appropriate HR for the Northern Shoveler at spring stopover is 8.49 ± 5.95 km² (mean ± standard error).

Nest site selection by an endangered raptor, the Grey Goshawk (Accipiter novaehollandiae), in a hostile anthropogenic landscape

ABSTRACT The Grey Goshawk is an endangered raptor occurring at low densities throughout its Tasmanian range. Nesting ecology and conservation requirements of the species are poorly understood. Thus, knowledge of nest site selection and breeding habitat preferences is needed to inform conservation management strategies. Here, we investigate nest site selection in a modified anthropogenic landscape in south-east Tasmania, Australia based on 75 active nest sites. Our logistic regression models show that nest site selection is influenced by a range of variables at the landscape, nest stand and nest site level, which likely relate to territoriality, food availability and forest structure. We also used environmental and disturbance-related variables to deliver a management-specific model, which indicated distance to track, dwelling and drainage lines were significant predictors of nest site selection. Our results can be used to improve conservation management and planning strategies.

Multi-Annual Study of Eriogaster catax (Linnaeus, 1758) (Lepidoptera, Lasiocampidae) Oviposition Strategy in Transylvania's Largest Population: Key Insights for Species Conservation and Local Land Management.

This study provides new insights into the oviposition strategy of Eriogaster catax (Linnaeus, 1758) (Lepidoptera, Lasiocampidae), an endangered species of moth found in semi-natural habitats within agricultural landscapes. Protected under various European directives and listed as Data Deficient by the IUCN, E. catax inhabits warmer regions of the Western Palearctic. Despite noted geographic variations in its ecological preferences, few studies have statistically significant data on its ecology. Our six-year study, conducted within the largest known population of E. catax. in Romania, reveals critical data on its oviposition preferences, including the species' tendency to utilize Prunus spinosa L. and Crataegus monogyna Jacq. shrubs at an average height of 80.48 ± 34.3 cm, with most nests placed within the 41-80 cm range and containing an average of 186 ± 22 eggs. The study also addresses the species' vulnerability to human activities such as bush trimming, agricultural burning, and uncontrolled grazing, particularly due to its low oviposition height. These findings underscore the negative impact of overgrazing and burning practices, particularly when conducted on a large scale, on the conservation of E. catax. The detailed ecological requirements identified in this study are essential for developing effective conservation strategies and habitat management practices. Furthermore, the study highlights the importance of local community involvement and public education in raising awareness about biodiversity and the conservation of endangered species.

Detailed biogeographical mapping as a useful novel tool for the conservation of endemic taxa: a case of study for Iberian orchids

Background Iberian orchids occur in plant communities designated as habitats of interest in the European Union, particularly in Mediterranean forests. Their ecological importance highlights the need for a deeper understanding of their distribution and ecological requirements in order to develop effective conservation and management policies. Methods This study focuses on the biogeographical mapping and characterisation of five Iberian and Balearic endemic orchid species at district level. Distribution data were collected from existing biodiversity databases and integrated into a Geographic Information System (GIS). In order to assign the correct biogeographical epithet to each taxon, a set of rules and criteria was developed to ensure an objective, simple and universal classification based on the species' distribution areas. Results For each orchid species, the study identified its phytosociological assignment, bioclimatic range and current conservation status. Detailed maps were produced, providing insights into the biogeographical, bioclimatic and phytosociological attributes of these taxa. Conclusions The biogeographical mapping and ecological classification presented in this study provide a basis for effective decision-making regarding the conservation and management of these orchid species. In addition, the results can be used to update their conservation status to better reflect their ecological needs and threats.

Optimal operation model of ecological flow of hydropower station based on genetic algorithm and neural network

Amid diverse water demands, the conflict between ecological flow adjustments and power generation flow adjustments in hydropower station water resource dispatching, coupled with an increasing diversity of constraints, complicates the issue of water resource optimization and dispatching. How to scientifically develop feedback regulation mechanisms to promote a virtuous ecological cycle, fine tune existing hydropower station scheduling plans, and achieve multi-objective optimization scheduling is the core issue in researching the comprehensive utilization of water resources. This study establishes a reservoir flow regulation model with the objective functions of maximizing power generation and achieving optimal average ecological protection. The model, constrained by water balance, reservoir capacity, unit output, and unit overflow, was optimized and solved using the genetic algorithm-backpropagation neural network (GA-BPNN) approach. This study establishes a reservoir flow regulation model with the GA-BPNN algorithm was applied in multi-objective optimization to identify an optimal solution that maximizes overall system performance while adhering to ecological flow constraints. The results indicate that the optimized plan has performed effectively in hydropower station operations. It not only satisfies ecological flow requirements, but also significantly enhances power generation efficiency. Specifically, power generation increased by 32,680 kw·h, a 23.85% growth rate. The optimized plan significantly enhances the comprehensive utilization efficiency of water resources. It offers a scientific basis for the rational planning, dispatching and utilization of water resources in hydropower stations and reservoirs.

Knowledge shortfalls on amphibian diets in Colombia: Future trends and challenges

AbstractAmphibians are increasingly threatened, leading to growing concern about their key role in natural ecosystems globally as predators and essential consumers in food webs. Effective conservation plans are linked to up‐to‐date distributional and ecological information, but dietary knowledge is often underrepresented. This information is essential for understanding ecological requirements, changes in the species and populations, impacts of habitat modification, and developing conservation strategies. Here, we present the current knowledge on amphibian diets in Colombia, to determine (a) the number of species studied and their distribution across families and genera; (b) the temporal and regional patterns in number of articles on amphibian diets; and (c) the trends in topics studied associated with amphibian diets; and to offer (d) a qualitative description of amphibian diets and the methods used for stomach contents collection. We found 70 published studies on the diet of Colombian amphibians between the years 1914 and 2022, including 100 species (11.6% of Colombian species). The Andean region is the best represented, and the Amazon and Orinoco the least. The topics most frequently studied were prey items consumed and ontogeny, followed by systematics and taxonomy, and land‐use change impacts. Forty‐one prey items were consumed, where Coleoptera and Hymenoptera were the most common prey items. While the development of information on amphibian diets has recently increased, knowledge remains limited, with a significant information gap for many Colombian species in different regions. Conducting studies in little‐explored areas of the country, especially the Amazon, Orinoco, and Pacific regions, should have high priority. Investigations should be focused on Caudata and Gymnophiona, plus the anurans of the Hemiphractidae and Pipidae families that do not have diet records in Colombia. Indeed, we evidence the necessity to perform trophic network analysis to understand better the energy flow between species and the associated spatial, temporal, or functional trait changes.

Characteristics of Oak (Quercus petraea (Matt.) Liebl), hornbeam (Carpinus betulus L.) and ash (Fraxinus excelsior L.) in a plain-low hills-mountains-plateau sequence

The climate has changed significantly over the past few decades around the globe. To make meaningful comparisons between changes occurring over time in the tree world, comprehensive databases on the most important species and their evolution must be created. It is essential to consider latitude, longitude, altitude and local relief when analyzing data. Given the extensive distribution of oak, hornbeam and ash, a sequence analysis was conducted to definitively examine the characteristics of these species in West Plain, West Hills, Apuseni Mountains and Transylvania's Tableland. The data for all the regions comprised a total of 708511 ha, which were subjected to rigorous analysis to determine characteristics such as yield class, volume, increment, structure and participation percentage. The data was analyzed using the most appropriate modern statistical programs, including correlation matrices, ANOVA, principal component analysis, matrix data analysis and the cluster method. In relation to the altitudinal variation, oak is present at average altitudes of 200-250 m in West Plain, 400-500 m in West Hills and Transylvania's Tableland, and 900-950 m in Apuseni Mountains. Hornbeam has a similar spreading with oak, but records its presence in slightly higher altitudes of West Hills (400-700 m) and lower in Apuseni Mountains (700-750 m). Volume is also an important indicator, as it is susceptible to climate change. Oak has the highest age-volume, over 95 years, while ash and hornbeam have it less than 90 years. The results are crucial for understanding the ecological requirements of oak, hornbeam and ash, as well as for effectively managing these forests.

Modelling Environmental Tree Species’ Volume using some selected Skewed Distributions

Ecological requirements' knowledge in determining tree species' distributions is a precondition for sustainable forest management. Tree species in all regions are threatened by climate change but some are more vulnerable than others. Rightly skewed distributions were used to take care of the environmental data set obtained from FRIN using five species which are: Beech Wood, White Afara, Opepe, Afon and Teak. Appropriate statistical tools distributions like descriptive analysis, Akaike Information Criterion (AIC), Goodness of Fit, Probability Functions, Kolmogorov Smirnovt-test, Gamma, Weibull, Log-normal and Beta-weibull were carried out to determine the best distribution for each selected specie in this research. It was established from the distributional pattern of the tree species' volume used in this research that the Gamma distribution was a better fit for the Beech wood with the AIC of 617.21, Beta-weibull distribution was a better _t for the White Afara, Opepe and Teak Species with the AIC values of 580.772, 630.84 and 733.60 respectively while the Weibull distribution was a better fit for the Afon specie with the AIC value of 752.07. Conclusively, the implication of the analysis is that the Beta-weibull distribution described the tree species' volume best among the four distributions used. In line with the findings, it is recommended that Beta-weibull should be the appropriate distribution to model forest specie when it comes to modelling because of its four (4) parameters and its goodness when fitting.

Spore viability of fern species of the genera &lt;i&gt;Amauropelta&lt;/i&gt;, &lt;i&gt;Blechnum, &lt;/i&gt;and &lt;i&gt;Physematium&lt;/i&gt; from central Argentina after low temperature storage

Background and aims: Ferns are sensitive to environmental changes, inhabiting ecosystems susceptible to degradation. Spore banks and in vitro spore culture are useful tools employed in their conservation. The objective was to test the ability of the spores to germinate after being stored in a freezer and to develop gametophytes and sporophytes, in native fern species of genera Amauropelta, Blechnum and Physematium. M&amp;M: Spores of A. argentina, B. auriculatum and P. montevidensis were stored at -20 ºC in dry conditions for 6 and 12 months. They were sown in vitro in Dyer liquid medium and incubated in a growth chamber. The means of germination percentages were calculated and a one-way Student’s t-test was employed. Gametophyte and sporophyte development was registered under light and stereoscopic microscopes. Results: Depending on the species, statistical differences were recorded in germination percentages (viability) between both storage periods. The spores of A. argentina kept in freezer for 12 months completely lost viability. In B. auriculatum, viability decreased over time, and in P. montevidensis it remained constant. Gametophytes and sporophytes developed in all cultures; except in A. argentina spores, with 12 months in freezer. Conclusions: The viability of the spores under dry storage at low temperature could be conditioned by the ecological requirements of the species. Protocols used for spore storage and culture allowed obtaining gametophytes and sporophytes in trials.

Exploring the effects of the assisted transfer of European beech (Fagus sylvatica L.) provenances in the Romanian Carpathians

The genetic inheritance of a tree species is fully expressed in the phenotype only when its ecological requirements are accomplished. Therefore, genetic tests provide the opportunity to simulate the change in the environment and determine the most suitable site conditions for specific populations. In light of the unpredictable climate conditions resulting from rapid environmental changes, the current study investigated possible signs of adaptation and productivity of European beech in the Romanian Carpathian region. For this purpose, the tree growth and stability performances, as well as the transfer effect, were examined in 17 international beech provenances tested in two different environments for 27 years. Growth and stability performances were evaluated using tree height (Th), breast height diameter (DBH), and survival (S). In the case of the transfer analyses, the ecodistance approach was applied. According to the results, the average of S was 13% higher in the Carbunari provenance trial, and DBH was higher in the Sacele trial by 15%, while no noticeable differences were registered for Th. The best-performing provenances were those originating from similar site conditions to the Romanian test sites, and the transfer function detected the sensitivity of beech provenances to increasing temperature. The general transfer response of provenances revealed a similar performance across sites and suggested that provenances exhibited adaptation and acclimation to the test environments from Romanian Carpathians.

Water Resources Management for Multi-Source Ecological Restoration Goals in an Oasis: A Case Study of Bohu County Irrigation Area in Xinjiang, China

Oases in arid regions consist of river–lake–groundwater systems characterized by complex hydrological cycles and fragile ecosystems. Sustainable water resource management, aimed at multi-source ecological restoration, is crucial for oasis ecological protection and represents a current research challenge. This study focuses on the Bohu irrigation area, using ecological water levels, the MIKE-SHE hydrological model, and the water balance equation to propose a multi-objective groundwater and surface water regulation scheme that meets both the ecological safety requirements of the irrigation area and the ecological water demands of the Small Lake. Key findings include the following: (1) The regional ecological water level ranges from 1.69 m to 4 m, with about 74% of the area exceeding this range, threatening local ecology. (2) The proposed regulation method adjusts 91.25% of areas exceeding the ecological water level to within the acceptable range. (3) Under various planting scenarios, the minimum water distribution from the west branch of the BLSM water diversion hub should be 824.632 × 106 m3/a to meet Small Lake ecological demands. When this volume exceeds 831.902 × 106 m3/a, both groundwater regulation and Small Lake ecological demands are satisfied. This paper quantifies the water cycle mechanisms in complex hydrological interaction areas, providing specific solutions to regional ecological problems, which holds significant practical relevance.

Mitigating the extinction risk of globally threatened and endemic mountainous Orthoptera species: Parnassiana parnassica and Oropodisma parnassica

Abstract Orthoptera species are vulnerable to extinction on a global scale. Greece hosts 35% (380 species) of the European Orthoptera fauna with a high degree of endemic (37%) and threatened species (37%). We sampled 46 plots (100 m2) to investigate the distribution and ecological requirement of two Greek mountain endemic and red‐listed species: Parnassiana parnassica (Ramme, 1926; Orthoptera: Tettigoniidae; Critically Endangered [CR]) and Oropodisma parnassica (Scudder, 1897; Orthoptera: Caelifera; Endangered [EN]). Species had a restricted geographical range, with two isolated populations confined to high altitudes (1527–2320 m) of Mts. Parnassos and Elikonas. Species distribution models showed that slope affected their suitable habitat, together with the topographic position index and the annual temperature range (P. parnassica), and the amount of green vegetation and evapotranspiration (O. parnassica). Connectivity analysis showed that P. parnassica‐suitable habitat consisted of few larger and well‐connected patches (26 patches: effective mesh size of 1.57 km2) and that O. parnassica‐suitable habitat consisted of more but smaller and less connected patches (56 patches: effective mesh size of 0.3 km2). Generalised linear models showed that the population density of P. parnassica was negatively influenced by the height of herbaceous vegetation and that of O. parnassica was positively influenced by altitude. The species face three main imminent threats: land take, wildfires and global warming, whereas livestock grazing seems to have a positive impact and skiing a neutral impact on their populations. We assessed both species as EN after International Union for Conservation of Nature (IUCN) criteria and a suite of conservation measures are suggested for their status improvement.

Low altitude Vaccinium myrtillus L. populations in the Eșelnița Valley (Danube Gorge, Carpathian Mountains, Romania)

The presence of certain species in habitats and at altitudes different from their usual ecological requirements has great biogeographic importance. Such a situation was identified in 2023 on the middle and lower course of Eșelnița Valley, a Danube tributary in the Carpathian Mountains in southwestern Romania. Thus, in Eșelnița Valley, we identified Vaccinium myrtillus and Calluna vulgaris species in beech forests at low altitudes. The lowest altitude with V. myrtillus in Eșelnița Valley was 198 m (approximately 5 km upstream from the Danube). On Eșelnița Valley, other species related to mountain areas are also present at low altitudes, favored by the narrow shape and the cooler microclimate of the valley.