Seasonal Dynamics Research Articles

Characterizing ground ice content and origin to better understand the seasonal surface dynamics of the Gruben rock glacier and the adjacent Gruben debris-covered glacier (southern Swiss Alps)

Abstract. Over the recent years, there have been focused international efforts to coordinate the development and compilation of rock glacier inventories. Nevertheless, in some contexts, identifying and characterizing rock glaciers can be challenging as complex conditions and interactions, such as glacier–rock-glacier interactions, can yield landforms or landform assemblages that are beyond a straightforward interpretation and classification through ordinary visual means alone. To gain a better understanding of the spatial and temporal complexity of the ongoing processes where glacier–permafrost interactions have occurred, the characterization of the subsurface of the Gruben rock glacier and its adjacent complex contact zone with the then more extended Little Ice Age Gruben glacier is quantitatively assessed using a petrophysical joint inversion (PJI) scheme, based on electrical resistivity (ERT) and refraction seismic (RST) data. Surface dynamics are assessed using both in situ and close-range remote sensing techniques to monitor daily and seasonal displacements and to monitor landform-wide surface changes at high spatial resolution, respectively. Both the geophysical and geodetic surveys allowed two zones to be identified: the rock glacier zone and the complex contact zone where both permafrost and embedded surface ice are present. In the complex contact zone extremely high ice contents (estimated up to 85 %) were found. Widespread supersaturated permafrost conditions were found in the rock glacier zone. Surface displacement rates in this zone are typical of permafrost creep behaviour, with a gradual acceleration in late spring and a gradual deceleration in winter. Moreover, the coherent nature of the rock glacier zone surface deformation contrasts with the back-creeping and slightly chaotic surface deformation of the complex contact zone. Favouring a multi-method approach allowed a detailed representation of the spatial distribution of ground ice content and origin, which enabled us to discriminate glacial from periglacial processes as their spatio-temporal patterns of surface change and geophysical signatures are (mostly) different.

Transcriptomics and metabolomics insights into the seasonal dynamics of meat quality in yak on the Qinghai-Tibetan Plateau

BackgroundMeat quality in yak is influenced by the fluctuation of nutritional composition in different grazing seasons on the Qinghai-Tibetan Plateau. However, the molecular mechanism underlying in yak meat remains unknown. Therefore, this study aimed to investigate the seasonal dynamics of meat quality in yak by transcriptomics and metabolomics techniques. Twelve healthy female yaks with a similar weight were divided into two groups, including the warm season group (WS) and cold season group (CS). After slaughter, samples of longissimus lumborum were collected and subjected to transcriptomics and metabolomics to explore the effects of different seasons on meat quality.ResultsYak in the WS group had higher contents of n-3 Polyunsaturated fatty acid (PUFA), n-6 PUFA, threonine, and valine compared to the CS group, but the pH45min and b* values were lower. A total of 75 differentially expressed metabolites in the longissimus lumborum muscle were identified, with 23 metabolites upregulated and 52 metabolites downregulated in the WS group. These metabolites were mainly enriched in the pathway of glycine, serine and threonine metabolism, tryptophan metabolism, and carbohydrate digestion and absorption. In comparison, the WS group exhibited 262 upregulated genes in the longissimus lumborum muscle and 81 downregulated genes relatives to the CS group, which were enriched in the fat deposition of TGF-beta, ECM-receptor interaction, MAPK, and PPAR signaling pathway.ConclusionsAmong these, downregulated genes NPNT, GADL1, SESN3, and CPXM1 were associated with lipid metabolism and fat deposition in grazing yaks. It was found that DDC, DHTKD1, CCBL1, GCDH, and AOC1 involved in the tryptophan metabolism played an important role in the regulation of energy metabolism in yak.

Dynamics of the content of mineral elements and effective fertility of alluvial meadow soil in vegetable crop rotation

In vegetable crop rotation with different fertilization systems of vegetable crops, the dynamics of the content of mineral elements of plant nutrition was determined, effective soil fertility was evaluated in comparison with potential under experimental conditions, and the most effective fertilizer system was identified not only to obtain the highest yields, but also to preserve and reproduce the potential fertility of alluvial meadow soil. The study was conducted in 2015–2019 in the Ramensky district of the Moscow region on the alluvial meadow medium loamy soil of the central floodplain of the Moscow River. The seasonal dynamics of the content of 3 elements of plant mineral nutrition (nitrate nitrogen, mobile phosphorus and potassium) in the carrot – beet – cabbage crop rotation was studied, using 3 main fertilization systems for vegetable crops (mineral, organic, organo-mineral). It was found that the maximum content of nitrate nitrogen (on average in crop rotation 47.4 mg/kg) and mobile potassium (on average 156 mg/kg) occurred in the third decade of June. The content of mobile phosphorus in the soil was high (200 mg/kg) at all accounting periods. A close correlation was determined between the yield of root crops and cabbage with the average content of nitrate nitrogen in the soil during the growing season (r = 0.735–0.934), mobile phosphorus (r = 0.539–0.972) and potassium (r = 0.532–0.976). The effective soil fertility of the site under 3 crops per crop rotation had the following characteristics: when using a mineral fertilizer system, the content of nitrate nitrogen was 21.3, organic – 10.1, organo-mineral – 22.1 mg/kg, the content of mobile phosphorus when using a mineral system – 40.4, organic – 34.1, organo-mineral – 47.9 mg/kg, the content of mobile potassium is 44.4, 20.6, 50.8 mg/kg, respectively. It was found that under crops of carrots and beets, the potential fertility of the soil during crop rotation was reproduced with the use of mineral (recommended dose of NPK) and organo-mineral fertilization systems of these crops, and the yield of carrots (67–69 t/ha) and beets (67–68 t/ ha) under these systems was high, more than expected estimated 60 t/ha. Under cabbage, late soil depletion also did not occur when using the recommended mineral and organo-mineral fertilizer systems, yields of 78 and 81 t/ha were close to the expected estimated yield of 80 t/ha. At the same time, the organo-mineral system had an advantage: during crop rotation, it retained 13% more nitrate nitrogen in the soil, 8% more mobile phosphorus and 40% more mobile potassium than the mineral one. One and a half and double doses of mineral fertilizers for late cabbage led to a significant increase in its yield (85–90 t/ha), but at the same time a significant part of nitrogen (on average for the season 33–41 mg/kg) was irretrievably lost in the soil.

Exploring the distribution and abundance of groundnut sucking bug (offa) [Rhyparochromus littoralis Dist] across major groundnut-producing regions in North-Eastern Nigeria

A multi-locational survey was conducted across Adamawa, Gombe, and Taraba States during the 2021 and 2022 cropping seasons to assess pest dynamics and their impact on groundnut production. This research delves into the intricate dynamics of groundnut pest management, focusing on the prevalence, abundance, and diversity of Rhyparochromus littoralis, a significant insect pest in groundnut cultivation, in the study area. Groundnut (Arachis hypogaea L.) serves as a vital cash crop in Nigeria, contributing substantially to the economy and livelihoods of many farmers. However, the presence of insect pests such as R. littoralis poses a considerable threat to groundnut production, warranting comprehensive studies to elucidate their behaviour, impact, and management strategies. The study meticulously examines the seasonal and spatiotemporal dynamics of R. littoralis within the major groundnut-producing areas, shedding light on its prolific nature characterized by rapid reproduction and high population densities. Through rigorous surveys and data analysis, R. littoralis emerges as a formidable adversary, establishing its status as a major insect pest in the Northeast geo-political zone. The survey conducted on the abundance of the groundnut-sucking bug, Rhyporachromus litoralis Dist, in Adamawa State during the 2021 and 2022 cropping seasons reveals several noteworthy findings. The abundance of R. litoralis varied across different locations and cropping seasons. In 2021, the insect abundance ranged from 2075.67 to 2578.83 across different locations, whereas in 2022, the abundance ranged from 2075.00 to 2677.58. Statistical analysis indicates a significant difference in insect abundance between the two years, with p-values less than 0.0001 for both years, highlighting the reliability of these differences. In this study, the presence of the groundnut-sucking bug in groundnut fields was reported in early September in Gombe, while in Adamawa it was in late September but in Taraba, it was in Late October. By shedding light on the complex interactions within the groundnut ecosystem, this study contributes to a deeper understanding of pest dynamics and underscores the importance of coordinated strategies to safeguard groundnut production in Nigeria's Northeastern region

Effects of the reopening of the Grand-Bassam inlet on the seasonal dynamics of some trace metals in the superficial sediments from the area II of the Ébrié system

The objective of this work was to assess the impacts of the permanent reopening of the Grand-Bassam inlet on the seasonal dynamics of thirteen trace metals in the superficial sediments of the area II from the Ébrié system. In its implementation, the sediment samples were collected over a year (from May 2023 to April 2024). The concentrations of these trace metals were obtained by inductively coupled plasma mass spectrometry (ICP MS) according to ISO 17294-2 after dissolution according to NF X31-147. The results showed a significant input of these metals by meteorological inputs during the rainy, cold, and flood seasons, except for Cr, whose presence in these substrates was mainly related to the strong marine intrusion during the hot season. The modification of the geochemical and physical characteristics due to the reopening of this pass significantly influenced the presence of these trace metals in these substrates during the study period. A reduction in the use of inputs containing high concentrations of trace metals and the efficient treatment of anthropogenic discharges with high metal content in the watershed of this ecosystem should be considered to support the depollution initiated with the reopening of this inlet.

Seasonal Dynamics of Ticks and Tick-Borne Pathogens in Republic of Korea

Tick-borne diseases are a public health problem and a significant burden on the livestock industry. The seasonal abundance of ticks and tick-borne pathogens strongly correlates with the prevalence of these diseases. To investigate the seasonal variation in ticks and tick-borne pathogens, ticks were collected from Gangwon State, Korea, and the tick-borne pathogens Borrelia, Anaplasma, Babesia, and Theileria were examined. In total, 14,748 ticks were collected, comprising ticks from two genera and three species: Haemaphysalis longicornis, Haemaphysalis flava, and Ixodes nipponensis, with H. longicornis being the predominant species. Of 7445 ticks (455 pools) examined for pathogens, Theileria was detected in 61 pools, whereas Borrelia and Anaplasma were observed in 17 pools. H. longicornis nymphs and adults were collected beginning in April, with nymph numbers peaking in May and June and adult ticks peaking in June and July. In contrast, the larvae were collected in May and peaked in September. Tick-borne pathogens were detected in April, peaking in July and September. Borrelia, the causative agent of Lyme disease, exhibits a temporal association between its detection in ticks and its occurrence in humans. In conclusion, tick-borne diseases seem to be closely linked not only to changes in tick numbers throughout the seasons but also to the seasonal variations of the pathogens within them.

Predicting the seasonal dynamics of Dalbulus maidis (Hemiptera: Cicadellidae) in corn using artificial neural networks.

This study addresses the challenge of predicting Dalbulus maidis (DeLong & Wolcott) (Hemiptera: Cicadellidae) density in cornfields by developing an artificial neural network (ANN). Over two years, we collected data on meteorological variables (atmospheric pressure, air temperature, dew point, rainfall, relative humidity, solar irradiance, and wind speed), plant age, and density of D. maidis in cornfields located in two Brazilian biomes (Atlantic Forest and Brazilian Tropical Savannah). Out of 1056 ANNs tested, the neural network featuring a 30-day time lag, six neurons, logistic activation, and resilient propagation demonstrated the lowest root mean squared error (0.057) and a high correlation (0.919) with observed D. maidis densities. This ANN exhibited an goodness of fit in low-density (Atlantic Forest) and high-density (Brazilian Tropical Savannah) scenarios for D. maidis. Critical factors influencing D. maidis seasonal dynamics, including corn plant age, rainfall, average air temperature, and relative humidity, were identified. This study highlights the potential of the ANN as a promising tool for precise predictions of pest seasonal dynamics, positioning it as a valuable asset for integrated pest management programs targeting D. maidis.

Seasonal dynamics of the absolute and relative mass of organs of male Wistar rats at the age of 3 months

Rationale. It is relevant to develop reference values of the “norm” and their ranges in physiology and pathophysiology when using animals of genetically purebred lines in different periods of ontogenesis and in different seasons of the year. The goal was to study the parameters of absolute and relative weight of the body and organs of sexually mature male Wistar rats at the age of 3 months in different seasons. Materials and methods. The study was conducted on 160 male Wistar rats aged 3 months. During the year, seasonal indicators of absolute and relative weight of the body, brain, spleen, thymus, liver, kidneys, adrenal glands, heart, lungs, and testes were measured. Results. The most constant seasonal changes were found in the absolute mass of all organs, while the values of the relative mass factors showed seasonal variability in only 50% jf cases. Synchronous seasonal changes were noted in the kidneys and adrenal glands. Whereas the thymus and spleen were characterized by the absence of simultaneity. The most pronounced seasonal variability in both mass indicators was found in the heart. Conclusion. Absolute organ mass is one of the most sensitive parameters when studying reference values, however, changes in relative mass factors should be considered. The importance of studying both indicators is explained by the fact that changes in organ mass often precede morphological changes. This study is one of the first in Russia in which reference ranges for the mass of the main organs of a healthy genetically homogeneous Wistar rats population at the age of 3 months were established, and the trend of their seasonal changes was generalized. Further study of the main causes of changes in organ mass in combination with anatomico-pathological data is necessary.

Hydrobiological and Geochemical Responses to Trout Cage Aquaculture in Lake Ecosystem

This study investigates the seasonal dynamics and interrelationships between geochemical and hydrobiological parameters in lake ecosystems impacted by fish cage farming in Lake Ladoga, Russia. Environmental conditions at three trout farms were assessed, focusing on water and sediment quality as well as benthic and zooplankton communities. For each farm, two categories of sampling sites were designated: cage sites and reference sites located 100–600 m away from the cages. Fieldwork was carried out across four seasons in 2023: February, June, August, and November. The findings indicate that intensive fish feeding results in significant organic waste accumulation beneath trout cages, altering the composition and abundance of planktonic and benthic organisms. The organic matter content in sediments beneath the cages during periods of intensive feeding was found to increase 2–5 times compared to the reference sites. In winter, accumulated organic matter in the sediments underwent mineralization, bringing hydrobiological indicators closer to the reference values. The geochemical and hydrobiological parameters analyzed in this study serve as valuable indicators for developing ecological monitoring approaches in freshwater cage aquaculture.

Composition, Seasonal Dynamics and Metabolic Potential of the Rhizosphere Microbiome Associated with Wild White Poplar

The white poplar (Populus alba) is a dioecious woody plant with significant potential for the phytoremediation of soils. To realize this potential, it is necessary to utilize growth-promoting microorganisms. One potential source of such beneficial microorganisms is the rhizosphere community of wild-growing trees. However, the structure, dynamics, and metabolism of the rhizosphere community of wild-growing white poplar remain poorly understood. To ascertain seasonal dynamics, species diversity, and metabolic potential, we sequenced 16S rRNA genes in metagenomes derived from 165 soil samples collected in spring and autumn from the root surfaces of 102 trees situated in disparate geographical locations. The three most prevalent phyla across all samples are Proteobacteria, Actinobacteriota, and Acidobacteriota. At the order level, the most prevalent orders are Sphingomonadales and Rhizobiales. Accordingly, the families Sphingomonadaceae and Rhizobiaceae were identified as dominant. The rhizospheric microbiome exhibited substantial inter-seasonal variation. Six families, including Caulobacteraceae, Xanthomonadaceae, Chitinophagaceae, Chthoniobacteraceae, Sphingomonadaceae, and Rhizobiaceae, exhibited alterations (spring-to-autumn) across all geographical locations under study. Members of the Rhizobiaceae family, which includes nitrogen-fixing bacteria, can provide poplar with plant-available forms of nitrogen such as nitrate and ammonium. The rhizosphere microbiome may facilitate the conversion of inorganic sulfur into sulfur-containing amino acids, cysteine and methionine, that are bioavailable to plants. Furthermore, the rhizosphere microbiome is capable of synthesizing amino acids, organic acids (including Krebs cycle acids), and some lipids and sugars. Consequently, the rhizosphere community can stimulate poplar growth by providing it with readily available forms of nitrogen and sulfur, as well as building blocks for the synthesis of proteins, nucleic acids, and other macromolecules. Many of these pathways, including nitrogen fixation, were subjected to seasonal changes.

A coupled multiscale description of seasonal Physical-BioGeoChemical dynamics in Southern Ocean Marginal Ice Zone

A coupled multiscale description of seasonal Physical-BioGeoChemical dynamics in Southern Ocean Marginal Ice Zone

Colder temperatures augment viability of an indirectly transmitted songbird pathogen on bird feeders

AbstractInanimate surfaces that are contaminated with infectious pathogens are common sources of spread for many communicable diseases. Understanding how ambient temperature alters the ability of pathogens to remain viable on these surfaces is critical for understanding how fomites can contribute to seasonal patterns of disease outbreaks. House finches (Haemorhous mexicanus) experience fall and winter outbreaks of mycoplasmal conjunctivitis, caused by the bacterial pathogen Mycoplasma gallisepticum (MG). Although bird feeder surfaces serve as an indirect route of MG transmission between sick and healthy individuals, the contributions of feeders to MG transmission in the wild will depend on how ambient temperature affects viability and pathogenicity of MG on feeder surfaces over time. Here, we used two experiments, with identical initial design, to assess such temperature effects. For both experiments, we pipetted equal amounts of MG onto replicate feeder ports held at night‐day temperatures representing summer (22–27°C) or winter (4–9°C). We allowed MG to incubate on feeders at either temperature and swabbed remaining inocula from surfaces at 0, 1, 2, 4, or 7 days post‐inoculation of the feeder, with each replicate feeder port only swabbed at a single time point. In the first study, we analyzed swabs using a culture‐based assay and found that MG incubated at colder versus warmer temperatures maintained higher viability on feeder surfaces over time. In the second study, we replicated the same experimental design but used MG swabs from feeder surfaces to inoculate wild‐caught, pathogen‐naïve birds and measured resulting disease severity and pathogen loads to determine pathogenicity. We found that MG remained pathogenic on feeder surfaces at cold ambient temperatures for up to one week, much longer than previously documented. Further, MG was significantly more pathogenic when incubated on feeders in colder versus warmer temperatures, with the strongest effects of temperature present after at least four days of incubation on feeder surfaces. Overall, cold ambient temperatures appear to alter the role of fomites in the MG transmission process, and temperature likely contributes to seasonal disease dynamics in this system and many others.

Seasonal dynamics shaping bacterial community structure and networks in a Multi Geomorphological Unit System (MGUS) within the eastern Ulansuhai Lake Basin, North China

Different geomorphological units such as mountains, forests, fields, grasslands, sands and water, despite their distinct morphologies, are interconnected through micro-ecosystems that collectively maintain the balance of regional ecology. However, there is a lack of research concerning the spatial correlation among different landscape micro-ecosystems within a catchment area, hindering a comprehensive understanding of watershed systematic evolution across various landscape micro-ecosystems. To address this gap, seasonal variations in bacterial community structure and ecological network connectivity were investigated across different geomorphological units in the eastern Ulansuhai Lake Basin, North China. Water and soil samples were collected in May (beginning of the growing season, 23 samples) and November (end of the growing season, 20 samples) 2021. The diversity of bacterial communities within the Multi Geomorphological Unit System (MGUS) comprising “mountain, forest, field, grassland, sand and water” increased from May to November due to precipitation and human cultivation influences. Environmental characteristics, such as water and soil variations, exert a greater influence on bacterial community structure than differences in landscape units. The stability of the macro-ecological network structure within the MGUS was relatively high, with “water” playing a pivotal role in connectivity (the average betweenness centrality value of “water” was more than twice that of the other landscape samples). This led to the gradual emergence of deterministic processes in the construction of the bacterial community, shifting from stochastic processes (90.8 % drift effect in May) to biotic interactions (29.2 % heterogeneous selection in November). Furthermore, the bacterial community structure exhibited “macroscopic stability, with ‘water’ assuming a central role, while also showing microscopic variations, reflecting fluctuations in the contribution of dominant bacterial genera to the network structure over time”. Our study offers a core information analysis aimed at characterizing the temporal and spatial evolution of microbial community structure within an MGUS, thereby addressing a gap in microbial macroecology.

Seasonal dynamics of micro- and nanoplastics and associated pollutants in Aarin River: Insights into abundance and digestion impact

Seasonal dynamics of micro- and nanoplastics and associated pollutants in Aarin River: Insights into abundance and digestion impact

Integrating river transport processes and seasonal dynamics to assess watershed nitrogen export risk

Integrating river transport processes and seasonal dynamics to assess watershed nitrogen export risk

Using machine learning to reveal seasonal nutrient dynamics and their impact on chlorophyll-a levels in lake ecosystems: A focus on nitrogen and phosphorus

Chlorophyll-a (Chl-a) is a pivotal indicator of lake eutrophication. Studies examining nutrients limiting lake eutrophication at large scales have traditionally focused on summer and autumn, potentially limiting the applicability of their findings. This study encompasses 86 state-controlled points in the Eastern China Basin, spanning data collected from January 2020 to July 2023. Furthermore, we focus on the application of three machine-learning models (i.e., eXtreme Gradient Boosting, Support Vector Machines, and Naive Bayes Classifier) to analyze the seasonal nutrient dynamics in lake ecosystems. We categorized the monitoring data by season to eliminate outliers and employed adaptive synthetic sampling to address data imbalance issues. The results reveal that the direct correlations between total nitrogen (TN), total phosphorus (TP), and TP in conjunction with turbidity and Chl-a are broadly weak, possibly because of geographic variations, nutrient lag effects on algae, and differences in algal community composition. However, probabilistic analyses revealed that as TP or TN levels transitioned from oligo-mesotrophic (O) to eutrophic (E), TP exhibited a greater influence on the variation in Chl-a status than TN during spring and winter (p < 0.05). Conversely, the effects of TP and TN on Chl-a (O-E) were comparable during summer and autumn. Seasonal variations in TN and TP thresholds derived from XGBoost modeling for O and E states of Chl-a suggest the need for stricter control measures during periods of high-nutrient levels and cost-effective management strategies to employ during low-nutrient periods. These findings should enhance our understanding of trophic shifts in lakes and provide a foundation for optimizing eutrophication management strategies across all seasons.

Study of Seasonal Dynamics of Microcystins and Nutrients in Studena Reservoir in 2023

This paper is a synthesis of data from studies conducted in 2023 on the seasonal dynamics of the presence of microcystin-LR and its homologues in water samples from Studena reservoir. A total of ten samples were collected from June to October 2023. The species composition of phytoplankton and the nutrients total nitrogen and total phosphorus were determined. The presence of microcystins was detected in three samples from the months of September and October (microcystin-LR concentration 0.38 and 0.75 μg/L in the water sample and in a scum at the reservoir wall in October; microcystin-RR 0.10 μg/L in September and 0.55 and 0.70 μg/L in the water sample and in a scum at the reservoir wall in October; microcystin-YR 0.27 and 0.48 μg/L in the water sample and in a scum at the reservoir wall in October). Trace amounts of microcystin-LR equivalents other than microcystin-RR and microcystin-YR were observed in water samples in June and July. The phytoplankton communities in the reservoir are persistently inhabited by blue-green algae. The presence of microcystins at concentrations close to the permissible level in the autumn sample indicates that at the time of sampling the bloom of cyanobacteria that produced the microcystins had passed and the toxins released remained in the water. Due to the near acceptable concentration of MC-LR in the autumn sample, serious consideration should be given to monitoring the reservoir during periods favourable for bloom formation.

Hydrophysical Characteristics of Lake Manzherok after Dredging

Data on seasonal and long-term dynamics of hydrophysical characteristics in the water area of Lake Manzheroksky (Altai Republic) after dredging in 2017–2018 are presented. The expedition studies were conducted during the ice age in April 2021, as well as the summer warming of the lake in July 2021 and 2023. The spectral index of light attenuation in the range of 400–800 nm, the relative transparency of water over a white disk, the velocity of water movement in surface and bottom horizons, as well as temperature stratification are studied. It was found that the discovered bottom groundwater sources contributed to the erosion and dissolution of the not completely removed silt layer, which determined high values of the spectral index of light attenuation and low relative transparency of the water. The research results in July 2023 showed significant changes in hydrophysical characteristics compared to 2021, indicating an improvement in the ecological condition of the lake in a long-term aspect for the period from 2018 to 2023.A comparison of spring and summer data on the dynamics of the spectral index of light attenuation at different depths for Lake Manzheroksky with other freshwater low-flow lakes showed that this hydro-optical parameter for the studied lake is maximum during the ice age, while for other lakes its minimum is noted in this phase of the annual limnic cycle.

Seasonal Dynamics of Caligus clemensi Infestation in European Seabass and Flathead Grey Mullet Integrating Morphological, Molecular, Immunological, and Environmental Perspectives

This case study investigates the seasonal prevalence, morphological characteristics, molecular identity, host immune response, and environmental factors influencing Caligus clemensi infestations in farmed European seabass and flathead grey mullet at a single marine fish farm. A total of 600 fish (400 seabass, 200 mullet) were examined over one year, revealing seasonal fluctuations in parasite prevalence and intensity. C. clemensi infestation peaked in winter for seabass (75% prevalence) and spring for grey mullet (80% prevalence), with notable declines in summer and autumn for both species. Morphological analysis confirmed C. clemensi as the causative agent, exhibiting sexual dimorphism and characteristic features including a quadrilateral cephalothorax and disk-shaped lunules. Molecular characterization of the 18S rRNA gene corroborated the morphological identification, with phylogenetic analysis revealing a well-supported monophyletic clade for C. clemensi within the family Caligidae. Quantitative real-time PCR demonstrated significantly elevated interleukin-1β (IL-1β) expression in infected fish, indicating a robust inflammatory response. Grey mullet and seabass exhibited high IL-1β upregulation. Histopathological examination revealed severe gill tissue damage, vascular changes, and hepatic steatosis in infected fish. Water quality analysis identified several parameters exceeding permissible limits, including total suspended solids (4800-5100 mg/L), total dissolved solids (32000 mg/L), sulfates (2300 mg/L), and chlorides (18000 mg/L). These elevated levels, likely associated with nearby oil production and refining activities, created conditions conducive to parasite proliferation. The high total suspended solids might provide substrates for C. clemensi settlement and attachment, while increased dissolved ions could stress fish and reduce their parasite resistance. This multidisciplinary case study revealed complex host-parasite interactions between C. clemensi and farmed marine fish, highlighting the need for improved water quality and targeted parasite control to enhance aquaculture sustainability in the Suez Canal region.

VEClim: An early warning decision support system for climate-sensitive vector activity and vector-borne disease risk assessment

Global warming and environmental changes affect vector species and vector-borne pathogen transmission, presenting significant public health challenges. We developed the Climate-Driven Vector-Borne Disease Risk Assessment platform (VEClim) to support early warning systems and decision support mechanisms, aiding the planning of effective vector control and outbreak management strategies. VEClim employs climate-sensitive structured population modelling, incorporating physiological processes driven by meteorological and environmental factors. A user-friendly web-based Geographic Information System (GIS) delivers a versatile interface to improve accessibility to the models and present short-, medium-, and long-range predictions of habitat suitability, vector activity, and disease risk and impact. The initial release of VEClim presents an in-depth assessment of the seasonal dynamics of Aedes albopictus, also known as the Asian tiger mosquito, and the associated risk of chikungunya virus transmission. This analysis compares three decades, i.e., historical (1980–1990), recent (2010–2020), and future (2090–2100), in terms of seasonal and geospatial averages. The results indicate persistent activity of the vector along the Mediterranean coast and a global northward shift of disease risk due to climate change. The VEClim platform is operationally maintained at The Cyprus Institute and is permanently available via its dedicated domain: veclim.com. VEClim offers environmental datasets, an open-source toolkit for researchers and modellers, and insights for public health officials and decision-makers.