Hasil untuk "General. Including nature conservation, geographical distribution"

James H. Brown, D. Mehlman, G. C. Stevens

Daniela Capatina, Aimene Gouasmi

This paper deals with the local recovery of conservative fluxes for an elliptic interface problem with discontinuous coefficients. The transmission conditions on the interface are imposed weakly and the discretisation is achieved by using conforming finite elements on unfitted meshes, with the aid of the CutFEM method. In a first attempt at flux reconstruction, we define a flux belonging to the Raviart-Thomas space of each sub-domain following the method developed for a boundary problem. However, the transmission condition is not satisfied by the recovered flux. In order to overcome this shortcoming, we propose a second approach, where the flux belongs to the recently introduced immersed Raviart-Thomas space. This ensures both the continuity of the normal flux across the interface and a natural conservation property on the cut cells. Subsequently, we apply the recovered flux to a posteriori error analysis and prove the sharp reliability of the error estimator.

Ruixing Ren, Junhui Zhao, Xiaoke Sun et al.

Vehicular Ad-hoc Networks (VANETs) serve as a critical enabler for intelligent transportation systems. However, their practical deployment faces a core governance dilemma: the network topology requires a dynamic trade-off between robustness against targeted attacks and ensuring low-latency information transmission. Most existing models generate fixed degree distributions, lacking the ability to adapt autonomously to the demands of diverse traffic scenarios. To address this challenge, this paper innovatively proposes a schedulable degree distribution model for localized VANETs. The core of this model lies in introducing a hybrid connection mechanism. When establishing connections, newly joining nodes do not follow a single rule but instead collaboratively perform random attachment and preferential attachment. Through theoretical derivation and simulation validation, this study demonstrates that by adjusting the cooperative weighting between these two mechanisms, the overall network degree distribution can achieve a continuous and controllable transition between a uniform distribution and a power-law distribution. The former effectively disperses attack risks and enhances robustness, while the latter facilitates the formation of hub nodes, shortening transmission paths to reduce latency. Experimental results based on the real-world road network of Beijing indicate that this model can precisely regulate node connection heterogeneity, attack resistance, and average transmission path length through the reshaping of the underlying topology. This provides a forward-looking and practical governance paradigm for constructing next-generation VANETs capable of dynamically adapting to complex environments.

M. Kennard, B. Pusey, J. Olden et al.

Lin Lin, Yuqing Guo, Guangzhao Wang et al.

BackgroundThe mangrove ecosystem has been severely threatened by the invasive species Spartina alterniflora for a long time. The macrobenthos diversity, as a biological indicator for assessing ecosystem sensitivity, can respond sensitively to the removal of the invasive S. alterniflora. Traditional morphological method has been commonly used to study macrobenthos diversity. However, it is difficult to comprehensively and accurately assess using traditional morphological method alone. Few studies have systematically assessed the effectiveness of environmental DNA in monitoring the diversity of macrobenthos in mangrove ecosystems.MethodsTraditional morphological method and eDNA metabarcoding (using COI primers) were combined to analyze changes in macrobenthos diversity in September (before S. alterniflora removal), October (after S. alterniflora removal but before mangrove planting), and December (after S. alterniflora removal and mangrove planting) of 2022 at the Quanzhou Bay Mangrove Wetland Nature Reserve, Fujian Province, China.ResultsThe results showed that 26 species were identified using traditional morphological method, while 212 species were identified through eDNA metabarcoding, especially more Arthropod were detected. However, no species were found to be common between the two methods at the species level. In terms of abundance, Arthropods and Annelids were the dominant groups for two methods, both 28.38% in the traditional morphological method and 38.38% and 32.94% in the eDNA metabarcoding, respectively. Additionally, the traditional morphological method indicated that following the removal of S. alterniflora, species richness, density, biomass, and diversity indices of macrobenthos initially declined, but subsequently showed a consistent recovery trend.DiscussionOur study suggests that eDNA metabarcoding has tremendous potential to monitor macrobenthos diversity, but shows low consistency in species with traditional method. For broader application in macrobenthos diversity using eDNA metabarcoding, further optimization is needed. Additionally, the results suggested that after the removal of S. alterniflora, macrobenthos diversity initially declined but gradually recovered, and long-term monitoring is warranted in order to better understand the changes in macrobenthos diversity with planting of mangroves.

M. Alecci, P. Jiménez, J. Samhi et al.

While mobile app evolution has been widely studied, geographical variation in app behavior remains largely unexplored. This paper presents a large-scale study of location-based Android app differentiation, uncovering two important and underexamined phenomena with security and fairness implications. First, we introduce GeoTwins: apps that are functionally similar and share branding but are released under different package names across countries. Despite their similarity, GeoTwins often diverge in requested permissions, third-party libraries, and privacy disclosures. Second, we examine the Android App Bundle ecosystem and reveal unexpected regional differences in supposedly consistent base.apk files. Contrary to common assumptions, even base.apk files vary by region, exposing hidden customizations that may affect app behavior or security. These discrepancies have concrete consequences. Geographically distinct variants can lead the same app to be labeled benign in one malware study but suspicious in another, depending on the region of download. Such hidden variation undermines reproducibility and introduces geographic bias into assessments of security, privacy, and functionality. It also raises ethical concerns about transparency and consent: visually identical Google Play listings may mask subtle but important differences. To study these issues, we built a distributed app collection pipeline spanning multiple regions and analyzed thousands of apps. We also release a dataset of 81,963 GeoTwins to support future work. Our findings reveal systemic regional disparities in mobile software, with implications for researchers, developers, platform architects, and policymakers.

Omid Reza Abbasi, Franz Welscher, Georg Weinberger et al.

As large language models (LLMs) continue to evolve, questions about their trustworthiness in delivering factual information have become increasingly important. This concern also applies to their ability to accurately represent the geographic world. With recent advancements in this field, it is relevant to consider whether and to what extent LLMs' representations of the geographical world can be trusted. This study evaluates the performance of GPT-4o and Gemini 2.0 Flash in three key geospatial tasks: geocoding, elevation estimation, and reverse geocoding. In the geocoding task, both models exhibited systematic and random errors in estimating the coordinates of St. Anne's Column in Innsbruck, Austria, with GPT-4o showing greater deviations and Gemini 2.0 Flash demonstrating more precision but a significant systematic offset. For elevation estimation, both models tended to underestimate elevations across Austria, though they captured overall topographical trends, and Gemini 2.0 Flash performed better in eastern regions. The reverse geocoding task, which involved identifying Austrian federal states from coordinates, revealed that Gemini 2.0 Flash outperformed GPT-4o in overall accuracy and F1-scores, demonstrating better consistency across regions. Despite these findings, neither model achieved an accurate reconstruction of Austria's federal states, highlighting persistent misclassifications. The study concludes that while LLMs can approximate geographic information, their accuracy and reliability are inconsistent, underscoring the need for fine-tuning with geographical information to enhance their utility in GIScience and Geoinformatics.

A. Chalfoun, F. Thompson, M. Ratnaswamy

Madeleine M. Ostwald, Kyra Sullivan, Lisa Stratton et al.

Recovering biodiversity across trophic levels is a major challenge in restoration ecology. Specifically, predator population recovery depends on the timely re-establishment of their preferred prey species in restored habitats. Here, we evaluate potential dietary factors contributing to the loss of western burrowing owls (Athene cunicularia hypugaea (Bonaparte, 1825)) from a newly-restored coastal grassland. We examined owl pellets and found that burrowing owl diets were relatively low in vertebrate prey during their brief occupation of the restoration site (2.6% of prey items; found in 61.8% of sampled pellets). We suggest that preferred food limitation may have been one contributor to the loss of owls from the restoration site. These findings suggest the need to prioritise re-establishment of prey communities for effective long-term recovery of burrowing owls in restored landscapes.

Christian W. Bauer, Zohreh Davoudi, Natalie Klco et al.

Simulating key static and dynamic properties of matter -- from creation in the Big Bang to evolution into sub-atomic and astrophysical environments -- arising from the underlying fundamental quantum fields of the Standard Model and their effective descriptions, lies beyond the capabilities of classical computation alone. Advances in quantum technologies have improved control over quantum entanglement and coherence to the point where robust simulations are anticipated to be possible in the foreseeable future. We discuss the emerging area of quantum simulations of Standard-Model physics, challenges that lie ahead, and opportunities for progress in the context of nuclear and high-energy physics.

Márton Horváth, Tibor Juhász, Imre Fatér et al.

The Hungarian population of the Eastern Imperial Eagle (Aquila heliaca) is closely monitored by MME BirdLife Hungary and the ranger service of the Hungarian national park directorates since 1980. The population is slowly, but continuously increasing during the last four decades and the average population growth rate is 11% and the number of estimated nesting population has increased from 230–240 pairs (2018) to 400–450 (2023).

Yangyang Yong, Ju Liang, Ju Liang et al.

The dynamic characteristics of atmospheric rivers (ARs) have been researched over the western North Pacific and East Asia due to their close linkage to disastrous precipitation extremes, while very little attention has been paid to the AR features from the western Pacific to Southeast Asia. This study aims to quantify the climatology, long-term trends and variability of different AR properties from the western Pacific to Southeast Asia using an objective identification algorithm, the ERA5 reanalysis dataset and the APHRODITE precipitation dataset for the period 1951-2015. The results indicate a belt of frequent AR activities from the western Pacific to the Andaman Sea during the boreal autumn-winter season. The long-term trend analyses show a significantly increasing trend in AR frequency and an eastward shift of AR plumes. These dynamic changes contribute to the increasing trend of extreme precipitation amounts in the coastal areas surrounding the South China Sea. The intraseasonal variability of the AR associated with the Madden-Julian oscillation (MJO) shows a pronounced enhancement of AR activity in the MJO phase-2 to phase-3 due to the steeper gradient of low-level geopotential height between the Northwestern Pacific and the tropical Indian Ocean. The modulation is partly explained by the enhanced MJO convection and the adiabatic heating in the vicinity of the trough of the 200-500 hPa geopotential thickness of the region. This study shows that ARs are important mechanisms behind the climatology, trends and variability of the regional precipitation in Southeast Asia. This study implies that more attention is required toward the dynamics of these tropical weather systems, particularly for their interactions with other synoptic processes and their response to future climate warming.

Ye Jin, Ye Jin, Qixuan Yu et al.

Regeneration is a complex process influenced by many independent or combined factors, including inflammation, proliferation, and tissue remodeling. The ocean, the most extensive resource on Earth, is rich in Seaweed. With increasing research in recent years, researchers have discovered that seaweed polysaccharides have various pharmacological effects, including a particular efficacy in promoting bone tissue regeneration. However, the application of this material in the field of bone tissue engineering is very limited. However, there are few studies on the polysaccharide at home and abroad, and little is known about its potential application value in bone repair. In addition, the bioavailability of the seaweed polysaccharide is also low, and there are still many problems to be solved. For example, the ease of solubility of fucoidan in water is a key issue that restricts its practical application. In this review, we summarize the applications and mechanisms of seaweed polysaccharides in bone healing. We also propose to combine seaweed polysaccharides with novel technologies through different types of preparations, hydrogels, scaffolds, and 3D printing to improve their use in tissue healing and regeneration.

Xi Liu, Mouyan Jiang, Mouyan Jiang et al.

MicroRNAs (miRNAs) are endogenous small non-coding RNAs that play important roles in several biological processes, including the regulation of body color. Leopard coral grouper (Plectropomus leopardus) is a valuable marine aquaculture fish; however, at present, there are no published reports on its early body color development. The skin color of P. leopardus undergoes a transition from transparent to red from 26 days post-hatching (dph) to 30 dph. In this study, we performed miRNA sequencing on 26 dph (Transparent, PT) and 30 dph (Red, PR) skin samples of P. leopardus to explore the molecular mechanism underlying red color formation. A total of 44.31 M and 37.55 M clean tags were obtained from PT and PR group, respectively. Among these tags, 981 miRNAs were identified, including 493 known and 488 novel miRNAs. A total of 106 differentially expressed miRNAs (DEMs) were identified in PT vs. PR, with 43 up-regulated and 63 down-regulated miRNAs in the PR group, compared to the PT group (|fold change| > 2 and p-value < 0.05). A miRNA-mRNA network based on 18 candidate miRNAs and 53 target genes related to pigmentation, and KEGG enrichment analysis of the target genes of all DEMs, revealed that miRNAs involved in the formation of red skin color were mainly related to: 1) the inhibition of melanin synthesis (miR-141-z, miR-206-z, miR-206-y, miR-27-z, miR-137-y, miR-204-x, miR-204-y, miR-211-x, miR-211-z); 2) chromatophore development (miR-206-z, miR-206-y, miR-499-y, miR-1-z, miR-2188-x, miR-423-x); and 3) carotenoid metabolism (miR-204-x, miR-204-y, miR-499-y). This study demonstrates the potential role of miRNAs in red color formation and lays the foundation for the molecular mechanism of body color polymorphism in P. leopardus.

Tom Barry, Tom Barry, Tom Christensen et al.

The Arctic Council working group, the Conservation of Arctic Flora and Fauna (CAFF) established the Circumpolar Biodiversity Monitoring Programme (CBMP), an international network of scientists, governments, Indigenous organizations, and conservation groups working to harmonize and integrate efforts to extend and develop monitoring and assessment of the Arctic’s biodiversity. Its relevance stretches beyond the Arctic to a broad range of regional and global initiatives and agreements. This paper describes the process and approach taken in the last two decades to develop and implement the CBMP. It documents challenges encountered, lessons learnt, and solutions, and considers how it has been a model for national, regional, and global monitoring programmes; explores how it has impacted Arctic biodiversity monitoring, assessment, and policy and concludes with observations on key issues and next steps. The following are overarching prerequisites identified in the implementation of the CBMP: effective coordination, sufficient and sustained funding, improved standards and protocols, co-production of knowledge and equitable involvement of IK approaches, data management to facilitating regional analysis and comparisons, communication and outreach to raising awareness and engagement in the programme, ensuring resources to engage in international fora to ensuring programme implementation.

Zihan Jin, Anzhou Zhao, Kaizheng Xiang et al.

[Objective] The temporal and spatial variation characteristics and driving factors of vegetation in the Guanzhong Plain urban agglomeration from 2000 to 2020 were studied in order to provide scientific guidance for the construction of regional ecological civilization. [Methods] Based on the Google Earth Engine (GEE) cloud platform, we used the enhanced vegetation index (EVI) data calculated from Landsat images from 2000 to 2020 combined with trend analysis, hot spot analysis, geographic detector model, and other methods to analyze the change pattern and driving factors of the annual maximum EVI (EVImax) in the Guanzhong Plain urban agglomeration. [Results] ① Annual EVImax showed a significant upward trend in the Guanzhong Plain urban agglomeration from 2000 to 2020. Annual EVImax values for the unchanged land use/cover types showed a fluctuating upward trend, among which the rate of increase for grassland was the largest. ② Spatially, the EVImax values showed a decreasing trend from south to north, and the high-value areas were mainly located in the Qinling Mountains in the southern Guanzhong Plain urban agglomeration. Trend analysis results showed that the areas where the annual EVImax increased and decreased significantly accounted for 70.16% and 3.61%, respectively, of the total area. ③ The spatial agglomeration characteristics of annual EVImax showed that the number of hot and cold spots showed a slight decrease and a significant downward trend, and the cold spots gradually transformed into sub-cold or sub-hot spots. ④ Precipitation was the most important factor affecting the spatial distribution of EVImax in the Guanzhong Plain urban agglomeration, and the interaction of each influencing factor was characterized as nonlinear enhancement or two-factor enhancement. [Conclusion] The vegetation of the Guanzhong Plain urban agglomeration showed an overall upward trend from 2000 to 2020, and annual precipitation was an important factor that determined vegetation growth status.

Yong Li, Wenxin Xie, Yang Yang et al.

IntroductionIn recent years, the adverse effects of escalating maritime trade and international shipping– particularly in regard to increased greenhouse gas emissions and their impact on human health– have come to the fore. These issues have thus instigated a surge in pressure to enhance the regulation of shipborne carbon emissions.MethodsThe study utilized the automatic identification system (AIS) data, Lloyd’s register data, and pollutant emission parameters to calculate the carbon emissions from the main engine, auxiliary engine, and boiler of vessels under varying sailing conditions, utilizing the dynamic method of ships. In relation to geographic information and ship trajectory, a comprehensive inventory of ship carbon emissions was developed, revealing pronounced spatiotemporal characteristics. To assure the accuracy of the substantial AIS dataset, procedures including data cleaning, trajectory integration, data fusion, and completion were executed. Such processes are indispensable, given the potential for transmission and storage errors associated with AIS data. To forecast CO2 emissions over diverse time intervals, a temporal fusion transformer model equipped with attention mechanisms was employed.ResultThe paper furnishes a case study on Tianjin Port, wherein a high-resolution carbon emissions inventory was devised based on AIS data acquired from vessels. This inventory was subsequently employed to generate multi-feature predictions of future carbon emissions. Given the optimal parameter configuration, the proposed method attained P50 and P90 values of 0.244 and 0.118 respectively, thereby demonstrating its efficacy.DiscussionRecognizing the sources of ship carbon emissions in this region and forecasting such emissions in the future substantiates that this method accurately portrays the laws of ship carbon emissions. Our study provides a scientific basis for decision-making in port and pollution management, enabling the creation of targeted emission reduction policies for ships.

Haili Ma, Haili Ma, Xiaotong Xiao et al.

Continental marginal seas are key systems in the global carbon cycle. Carbon stocks represent the ability to store carbon, thus quantifying the carbon stocks in marine sediments would help to better understand their importance in the carbon cycle. In this study, 17 sediment cores in the mud areas of the South Yellow Sea and the East China Sea were measured for total organic carbon (TOC) and its stable isotope (δ13C), and dry bulk density; and from which the carbon stocks and carbon stock accumulation rate as well as marine/terrestrial carbon stocks/carbon stock accumulation rate were calculated. The carbon stocks in the mud area of the South Yellow Sea showed a decreasing trend during 1855 to 1950 caused by the relocation of the Yellow River Estuary in 1855, but increased after 1950s due to increased sediment input via the enhancement of South Shandong Coastal Current. In the Min-Zhe belt of the East China Sea, carbon stocks showed an overall high marine proportion due to the phytoplankton bloom induced by high nutrient level, but the decreased carbon stocks in recent decades were mainly caused by the construction of reservoirs in the Yangtze River that reduced sediment transports. The average carbon stocks in 1 m sediments from the South Yellow Sea (45.2 t ha-1) and Min-Zhe belt (52.8 t ha-1) were low compared to that of global marine sediments (66.6 t ha-1), while the carbon stock accumulation rate showed much higher values (0.1 t ha-1 yr-1 in South Yellow Sea and 0.31 t ha-1 yr-1 in the Min-Zhe belt) because of higher sedimentation rates. Although carbon stocks of Chinese marginal seas were also lower than that of the tidal flats (70.7 t ha-1) and wetland (123.6 t ha-1) in China, their much larger area could store 0.75 Pg C in marine sediments. Our temporal records suggest that anthropogenic activities have reduced carbon stocks in the marginal seas since 1950, causing carbon to re-enter the atmosphere to impact climate changes.

S. F. Wilson, Wendy Crosina, E. Dzus et al.

Delineating relevant local populations of widely distributed species is a common challenge in conservation ecology. Caribou and reindeer ( Rangifer tarandus ) are in general decline throughout their global range, despite ongoing conservation efforts. In Canada, recovery actions for the threatened boreal population of woodland caribou ( Rangifer tarandus caribou ) are stratified by „local population units‟ (LPUs) on ranges distributed across 2.4 × 10 km 2 of the species‟ geographic range. To estimate local population dynamics, LPUs are assumed to be geographically closed, though supporting evidence varies widely. We assembled an exceptionally large database of GPS telemetry locations (891,306 telemetry days, 1998–2020) from 1,586 adult female caribou across the 19 northwesternmost LPUs. We generated a many-to-many Gaussian Bayesian Network to identify candidate local populations at range-level extents, as well as subpopulations, termed „communities‟ in network analysis. We detected local population boundaries that in some cases were consistent with accepted LPUs and consistent with the assumption of geographic closure. In other cases, local population boundaries did not map well to currently delineated LPUs. Several communities at smaller spatial extents were consistent with expert and local knowledge of caribou movements and support recovery planning and actions “stepped down” from entire ranges. Evidence consistent with population fragmentation was confirmed along the southern and southwestern boundaries of the species‟ geographic range within the study area, as were more continuous distributions confirmed to the north. We suggest that network analysis can help to inform conservation planning for boreal caribou and other wide-ranging species that would benefit from data-driven characterizations of multiscale population spatial structure.

Veronica Piazza, Abdusalam Uheida, Chiara Gambardella et al.

Microplastic pollution is receiving increased attention due to the realization of its hazards to aquatic and human life. Researchers across the globe are attempting to remove microplastics before its entry into the ecosystem. Therefore, the present work focused on the removal of microplastic from water and studied the potential risks for marine organisms and the ecosystem. The removal of model microplastics, polypropylene (PP) and polyvinyl chloride (PVC), has been studied by using photo-Fenton process. ZnO nanorods coated with SnOx(x < 2) layer and decorated with zero valent iron (Fe0) nanoparticles was used as heterogeneous catalyst for the removal of the microplastics in continuous water flow device. The obtained results demonstrated that high degradation efficiency of PP and PVC microplastics was achieved in a relatively short time and more than 95% of the average particle volume was reduced after 1 week of irradiation. The environmental impact of the photo-Fenton process of the microplastics degradation was investigated by using an ecotoxicological approach. An ecosafety screening has been performed through a series of experiments (bioassays) under controlled conditions, testing water samples after the photo-Fenton degradation of microparticles using a lab scale device. The ecotoxicological impact has been investigated by applying a battery of certified bioassays (UNI EN ISO/EPA standardized techniques) on aquatic organisms at different trophic levels (bacteria, algae, invertebrates). The results obtained on the three model organisms (A. fischeri, P. subcapitata, and D. magna) revealed no toxic effect for samples collected both before and after the photo-Fenton process, thus showing the absence of toxic by-products development during the degradation process.