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For the first time, two-year seasonal studies of phytoplankton production were carried out in the rocky–sandy littoral zone of the northern deep and cold-water Lake Onego. The research results showed that photosynthesis is characterized by two or three seasonal maxima, the values of which are within the limits of oligotrophic ecosystems. The main primary producers, the concentration of phosphorus in water, and the water temperature during the growing season are considered. Differences in the seasonal dynamics of photosynthesis and a similar level of seasonal average and maximum values were revealed in comparison with the deep-water region of the lake. The small contribution of littoral phytoplankton production to the primary productivity of the ecosystem is shown. [ABSTRACT FROM AUTHOR]

Root tips are the main components of absorptive fine roots, but their seasonal dynamics and relationship to environmental factors remain unclear due to the difficulties in methodology. In this study, we explored the temporal patterns of root-tip production and mortality in monoculture plantations of five temperate tree species at a common site in northeastern China, and identified the general environmental controls on such processes. We made monthly in-situ assessments of root tip length (RTL) production and mortality in two hardwood and three coniferous species with a minirhizotron (MR) method during the growing seasons of 2008 and 2009. Air temperature, rainfall, soil temperature and water content at 10 cm depth were determined concurrently. RTL production in all species exhibited consistent peaks in summer (June–August) in two growing seasons. RTL mortality showed substantial interannual and interspecific variability, with peaks in autumn and winter in 2008, but various patterns in 2009. RTL production positively correlated with monthly soil and air temperature across all species, and with monthly rainfall in three coniferous species. However, there was no significant correlation between RTL production and soil water content. By contrast, RTL mortality was weakly related to environmental factors, showing positive correlations with soil temperature in Korean spruce, and with rainfall in Korean pine and Korean spruce. Our findings suggest that the seasonal patterns of RTL production are convergent across the five temperate tree species due to the overlapped distribution of heat and rainfall, which can conduce roots to maximizing the acquisition of nutrient resources in the soil. [ABSTRACT FROM AUTHOR]

The spatial distribution and seasonal variation in heavy metal pollution in road dust in Liuzhou, China, were investigated. Road dust samples were collected during both drought and wet periods, and the concentrations of nine heavy metals—Cr, Ni, Cu, Pb, Zn, Cd, As, Sb, and Hg—were analyzed. The analysis showed that all nine heavy metals were higher than the background values of Chinese urban soils in both the drought and wet periods, and the mean heavy metal contents of road dust in the dry period were higher than those in the wet period, except for Cd. In the assessment of the pollution of heavy metals in road dust, the results of Igeo showed that Cd and Hg were significant; the results of NI showed that Cr and Ni were more significant. The spatial analysis shows that the industrial concentration areas in the north and west of Liuzhou City are concentration areas of heavy metal pollution. A Pearson correlation analysis showed high correlation between Cd in road dust heavy metals and Cd in the surrounding soil. Source identification via PCA revealed four main contributors: metallurgical and coal-fired industries, mechanical manufacturing, green belt maintenance, and waste treatment facilities. A quantitative analysis via APCS-MLR modeling confirmed that metallurgical and coal-fired industrial sources are the most widespread and important pollution sources in Liuzhou. There is a significant increase in the contribution of waste treatment sources to Hg contamination during wet periods. [ABSTRACT FROM AUTHOR]

Information about the population structure, including the age and sex composition, growth characteristics, and diet of fish, is essential for the conservation and sustainable exploitation of fish stock. The burbot, Lota lota, is the only freshwater species of the family Lotidae in the Amur (Heilongjiang) River catchment located in northeastern China. Information on the biological characteristics and data on the population structure of this fish from the Amur River are scarce. To study these factors in burbot, Lota lota, in the Amur River of China, 749 specimens from four sampling areas were taken and analyzed in October 2022, January 2023, and May 2023. The ages of the sampled fish ranged from 1+ to 7+ years. The female/male ratio was 1.04:1, and body length and mass varied from 175 to 595 mm and 73.5 to 1958.7 g, respectively. The length–weight regression parameter b value was estimated as 2.80. The parameters of the von Bertalanffy growth model were L∞ = 596, K = 0.221, and t0 = −0.771 for all sampled fish; L∞ = 625, K = 0.208, and t0 = −0.756 for females; and L∞ = 584, K = 0.219, and t0 = −0.980 for males. The analysis of the stomach contents showed fish to be the major source of nutrition across all areas and sampling periods. In January, the secondary prey of burbots in the Huma reach of the upper Amur River was aquatic insect larvae, while, in the Tongjiang and Fuyuan reaches of the middle Amur River, the secondary prey was shrimp. The mean stomach fullness index and rate of empty stomachs differed with the sampling area, with the greatest proportion of empty stomachs observed in the Luobei reach of the middle Amur River, and the lowest in the Tongjiang and Fuyuan reaches. The mean stomach fullness index showed the opposite trend. In the Huma reach, the contributions of fish to the diet and the mean stomach fullness index were significantly higher in May than in October and January. The study provides the first detailed information on the population age and sex structure, growth patterns, and feeding ecology of burbots from the Amur River, China. The results will aid in formulating management strategies and regulations for local populations of burbots in the Amur River, China. [ABSTRACT FROM AUTHOR]

Decades of persecution has resulted in the long‐term absence of grey wolves Canis lupus from most European countries. However, recent changes in both legislation and public attitudes toward wolves has eased the pressure, allowing wolves to rapidly re‐establish territories in their previous central European habitats over the last 20 years. Unfortunately, these habitats are now heavily altered by humans. Understanding the spatial ecology of wolves in such highly modified environments is crucial, given the high potential for conflict and the need to reconcile their return with multiple human concerns. We equipped 20 wolves, originating from seven packs in six central European regions, with GPS collars, allowing us to calculate monthly average home range sizes for 14 of the animals of 213.3 km2 using autocorrelated kernel density estimation. We then used ESA WorldCover data to assess the mosaic of available habitats used within each home range. Our data confirmed a general seasonal pattern for breeding individuals, with smaller apparent home ranges during the reproduction phase, and no specific pattern for non‐breeders. Predictably, our wolves showed a general preference for remote areas, and especially forests, though some wolves within military training areas also showed a broader preference for grassland, possibly influenced by local land use and high availability of prey. Our results provide a comprehensive insight into the ecology of wolves during their re‐colonisation of central Europe. Though wolves are spreading relatively quickly across central European landscapes, their permanent reoccupation remains uncertain due to conflicts with the human population. To secure the restoration of European wolf populations, further robust biological data, including data on spatial ecology, will be needed to clearly identify any management implications. [ABSTRACT FROM AUTHOR]

Seasonal dynamics of bacterial composition and functions were demonstrated for the biological fluidized-bed bioreactors combined in the anoxic/aerobic1/aerobic2 (AOO) coking wastewater (CWW) treatment sequences. The bacterial composition and functions in the CWW activated sludge samples were revealed by 16S rRNA genes amplicon sequencing. Thiobacillus, Cloacibacterium, Alkaliphilus and Pseudomonas were determined as core genera with seasonal changes. Mutable microbial community composition fluctuated in different seasons in same bioreactor. Distributions of predicted KEGG pathways along four seasons consistently demonstrated enrichment in biodegradation of carbon- and nitrogen-containing compounds. The major contaminants were removed from CWW by biochemical pathway of xenobiotics biodegradation and metabolism. This Level 2 pathway mainly owned the Level 3 pathways of benzoate degradation, drug metabolism-other enzymes, drug metabolism-cytochrome P450, metabolism of xenobiotics by cytochrome P450, and aminobenzoate degradation. The RDA results showed that dissolved oxygen with seasonal fluctuation was the main parameter shaping the microbial community. The observed dynamics within the microbial community composition, coupled with the maintained stability of CWW treatment efficiencies and a consistent profile of microbial functional pathways, underscore the presence of functional redundancy in the AOO bioreactors. The study underscored stable and effective operational performances of bioreactors in the AOO sequences, contributing the knowledge of microbiological basics to the advancement of CWW biological treatment. Key points: • Seasonal fluctuations of bacterial composition described for the AOO system. • Seasonal distributions of metabolic functions focused on carbon and nitrogen removal. • Functional redundancy was revealed in the AOO microbial community. [ABSTRACT FROM AUTHOR]

Background: The Anopheles Hyrcanus group, which transmits Plasmodium vivax, consists of six confirmed species in South Korea. An epidemiological study revealed differences in the seasonal occurrence patterns of each species. Pyrethroid resistance in An. sinensis dates back to the early 2000s, whereas information on pyrethroid resistance in other species is lacking despite their greater significance in malaria epidemiology. Methods: Anopheles mosquitoes were collected from two malaria-endemic regions in South Korea for 2 years and their knockdown resistance (kdr) mutations were genotyped. The larval susceptibility to λ-cyhalothrin was compared in six Anopheles species and its seasonal changes in three species were investigated. The full-length sequences of the voltage-sensitive sodium channel (VSSC) were compared across six species to evaluate potential target-site insensitivity. The contribution of the kdr mutation to phenotypic resistance was confirmed by comparing median lethal time (LT50) to λ-cyhalothrin between populations of Anopheles belenrae with distinct genotypes. Results: The composition and seasonal occurrence of rare species (Anopheles kleini, Anopheles lestri, and Anopheles sineroides) varied considerably, whereas An. sinensis occurs continuously throughout the season. A kdr mutation in the form of heterozygous allele was newly identified in An. belenrae, An. lesteri, An. pullus, and An. sineroides. The baseline susceptibility to λ-cyhalothrin was the highest in An. belenrae, followed by An. lesteri, An. sineroides, An. kleini, An. pullus, and An. sinensis, with median lethal concentration (LC50) values ranging from 6.0- to 73.5-fold higher than that of An. belenrae. The susceptibility of An. sinensis and An. pullus varied by season, whereas that of An. belenrae remained stable. The kdr-heterozygous An. belenare population exhibited 5.1 times higher LT50 than that of the susceptible population. Species-specific VSSC sequence differences were observed among the six species. Conclusions: Our findings suggest that the status and extent of pyrethroid resistance vary among Anopheles Hyrcanus group species. While An. sinensis, the predominant species, developed a considerable level of pyrethroid resistance through kdr mutation, the resistance levels of other species appeared to be less pronounced. Large-scale monitoring is crucial to fully understand species-specific seasonal occurrence and resistance status for effective management strategies, considering the ongoing impact of climate change on their vectorial capacity. [ABSTRACT FROM AUTHOR]

[Objective] To reveal the vertical distribution characteristics of soil organic carbon? nitrogen? and phosphorus content, soil stoichiometric characteristics (C/N, C/1y, N/P), enzyme activity, microorganisms, and their seasonal responses of forest stand types in Liziping Nature Reserve. _Methods］ The soils of Cyclobalanopsis and populus szechuanica broad-leaved mixed forest, Oriental oak deciduous broad-leaved forest, Fir-spruce coniferous mixed forest, and Yushania lineolata forest in the dry and rainy seasons were selected as the study objects to elucidate the effects of forest stand types on the stoichiometric characteristics of the soils, the enzyme activities, the microorganisms, and their seasonal dynamic response characteristics. Results] (1) The soil physicochemical properties and enzyme activity of the four forest stand types are higher in the rainy season than in the dry season, (2) The soil C/N in the Cyclobalanopsis-populus szechuanica broad-leaved mixed forest is higher in the dry season than in the rainy season, while the other three stands show the opposite trend. Dry season's C/1y are higher than the rainy season in Cyclobalanopsis and populus szechuanica broad-leaved mixed forest and Fir-spruce coniferous mixed forest, while the other two stands are the opposite. Dry season's N/P are higher than the rainy season in Oriental oak deciduous broad-leaved forest and Fir-spruce coniferous mixed forest, while the other two stands are the opposite. (3) Different forest types' value variation of soil C/N, C/I\and N/P are 17.0()〜37.33, 62.72〜114.5(), 3.09〜 5.18 in the dry season, and 17.72〜39.16, 63.21 〜9().72, 2.39〜5.8() in the rainy season. (4) The C/N and C/1y values during the dry and rainy seasons are higher than the national average (11.90, 61.00), indicating that nitrogen is limited during nutrient cycling and the potential for releasing I〉is low； The N/P values for both seasons were lower than the national average soil level (5.20)，indicating that the soil is more susceptible to N limitation； (5) The soil microbial activity of the four forest stand types is better in the rainy season than in the dry season, and the soil ecological stoichiometric characteristics are mainly influenced by enzyme activity and microorganisms. Conclusion] The results of this study can provide important theoretical basis for exploring the seasonal response mechanisms of regional soil nutrient decomposition, supply and limitation, as well as nutrient cycling processes. [ABSTRACT FROM AUTHOR]

Small pelagic fish (SPF) are crucial in marine food webs, transferring energy from plankton to higher trophic levels. This study focuses on herring (Clupea harengus) and sprat (Sprattus sprattus), addressing knowledge gaps in their feeding ecology in a nursery area, the Dutch Wadden Sea. We conducted a year-long, monthly survey, and used DNA metabarcoding to analyse zooplankton samples and stomach contents of two size classes of herring and sprat. Intra-, interspecific, and seasonal variations in fish condition, stomach fullness, and diet composition, along with selective feeding, were studied. Our study showed that condition and diet composition of herring and sprat, along with zooplankton density, exhibited a clear seasonal pattern. Juvenile herring and sprat displayed opportunistic feeding behaviour, rather than showing distinct prey selection. Besides copepods, we regularly observed (larvae of) benthic invertebrates in their diet. This emphasizes the crucial role of SPF as energy transfer agents, not solely between trophic levels, but also from benthic to pelagic habitats. Furthermore, fish post-larvae were part of the diet of larger herring (10–15 cm). Because of its unprecedented temporal and taxonomical detail, this study advances the understanding of seasonal dynamics of dominant components at the base of the Wadden Sea food web. [ABSTRACT FROM AUTHOR]

This study assessed the purse seine, handline and pole and line catches at PPS (Samudera Fishing Port Kendari) specifically targeting skipjack and yellowfin tuna in the Banda Sea. Although there has been a rise in tuna output over the past two years, the examination of fish size in September until November revealed substantial fluctuation. Additionally, the implementation of the moratorium policy had a detrimental effect. Ensuring the sustainability of fisheries in the Banda Sea, particularly for large pelagic fish like skipjack and yellowfin tuna, necessitates the implementation of adaptive management and selective fishing practices, with a particular focus on enforcing mesh size regulations. The aims of this study were to examine the patterns of tuna fisheries landing at PPS, specifically focusing on the sorts of catches made using purse seine, handline, and pole and line fishing methods. Additionally, the study aimed to assess the length frequency distribution of Thunnus albacares caught using purse seine, handline, and pole and line fishing gear. The methodology offers a thorough framework for evaluating the sustainability of Thunnus albacares fisheries in PPS Kendari. Policymakers can develop effective management plans for long-term resource sustainability by assessing catch composition, productivity, and size distribution across various fishing gears. The analysis of this study conducted in September-November 2023 revealed that the fish catches varied in size, ranging from 13 cmFL to 124 cmFL. [ABSTRACT FROM AUTHOR]

Key message: The growth rates of current-year shoots, fruits and trunks in apple trees peak sequentially during the growing season. The period of most intense growth coincided with the lowest NSC reserves. Vegetative and reproductive growth and storage are major carbon sinks in fruit trees; however, little is known about their mutual seasonal coordination. In this study, we monitored growth dynamics of trunks, fruits and current-year shoots together with the concentration of non-structural carbohydrates (NSC) in trees subjected to defoliation, early season flower thinning, mid-season fruit thinning and their respective combinations across the season. We found that defoliation had a negative effect on both trunk radial growth and annual fruit yield. Flower and fruit thinning caused lower fruit number per tree, but the individual fruits were larger resulting in a similar annual fruit yield among the treatments. Shoot extension growth was not significantly affected by the defoliation and flower and fruit thinning treatments. The concentration of non-structural carbohydrates was also similar across treatments. Modelled daily growth rates of shoots, fruits and trunks peaked sequentially one after another throughout the growing season with a delay of 15 and 18 days, respectively. The period of most intense growth of tree's organs corresponded well with the lowest NSC reserves and a temporary depletion of starch in 1-year-old branches. Taken together, our study illustrates a tight temporal coordination of major carbon sinks and improves our understanding of sink/source relations of commercially important apple trees. [ABSTRACT FROM AUTHOR]

Abstract Background The Anopheles Hyrcanus group, which transmits Plasmodium vivax, consists of six confirmed species in South Korea. An epidemiological study revealed differences in the seasonal occurrence patterns of each species. Pyrethroid resistance in An. sinensis dates back to the early 2000s, whereas information on pyrethroid resistance in other species is lacking despite their greater significance in malaria epidemiology. Methods Anopheles mosquitoes were collected from two malaria-endemic regions in South Korea for 2 years and their knockdown resistance (kdr) mutations were genotyped. The larval susceptibility to λ-cyhalothrin was compared in six Anopheles species and its seasonal changes in three species were investigated. The full-length sequences of the voltage-sensitive sodium channel (VSSC) were compared across six species to evaluate potential target-site insensitivity. The contribution of the kdr mutation to phenotypic resistance was confirmed by comparing median lethal time (LT50) to λ-cyhalothrin between populations of Anopheles belenrae with distinct genotypes. Results The composition and seasonal occurrence of rare species (Anopheles kleini, Anopheles lestri, and Anopheles sineroides) varied considerably, whereas An. sinensis occurs continuously throughout the season. A kdr mutation in the form of heterozygous allele was newly identified in An. belenrae, An. lesteri, An. pullus, and An. sineroides. The baseline susceptibility to λ-cyhalothrin was the highest in An. belenrae, followed by An. lesteri, An. sineroides, An. kleini, An. pullus, and An. sinensis, with median lethal concentration (LC50) values ranging from 6.0- to 73.5-fold higher than that of An. belenrae. The susceptibility of An. sinensis and An. pullus varied by season, whereas that of An. belenrae remained stable. The kdr-heterozygous An. belenare population exhibited 5.1 times higher LT50 than that of the susceptible population. Species-specific VSSC sequence differences were observed among the six species. Conclusions Our findings suggest that the status and extent of pyrethroid resistance vary among Anopheles Hyrcanus group species. While An. sinensis, the predominant species, developed a considerable level of pyrethroid resistance through kdr mutation, the resistance levels of other species appeared to be less pronounced. Large-scale monitoring is crucial to fully understand species-specific seasonal occurrence and resistance status for effective management strategies, considering the ongoing impact of climate change on their vectorial capacity. Graphical Abstract

Abstract Background Algae play important roles in urban river ecosystems and are the cornerstones of most water quality monitoring programs. Thus, a better understanding of algal community dynamics is needed to support sustainable management of water resources in urban rivers. Results In this study, we quantified the seasonal variations in planktonic and periphytic algal community structure in the highly urban Fenhe River and identified environmental factors affecting algal community structure and diversity. We monitored planktonic (drifting) and periphytic (attached) algal communities in the Taiyuan section of the Fenhe River over one year. The results indicated that Cyanophyta was the dominant phylum in both communities, followed by Bacillariophyta and Chlorophyta. Significant differences were observed in the composition of the planktonic and periphytic algal communities. In particular, the periphytic algal community was more diverse than the planktonic community. Water temperature and pH were the main environmental factors affecting planktonic and periphytic algal community structure, respectively, while nutrients were the most significant factor affecting planktonic and periphytic algal diversity. Ecological modeling indicated that the variations in the algal communities of the Fenhe River are mainly driven by stochastic processes. A co-occurrence network developed for the communities displayed positive interactions between the planktonic and periphytic algae. Conclusions These findings deepen our understanding of the seasonal interaction between planktonic and periphytic algae and the driving factors affecting community structure in the Fenhe River. They also provide a theoretical basis for the managing and protecting water resources in urban river ecosystems.

The aim of the study is to assess the seasonal supply of vitamin D and biogenic amines to practically healthy women of working age living in Arkhangelsk. Material and methods. The study sample included 20 practically healthy women aged 22–44 years, permanently residing in Arkhangelsk. The study was conducted over 4 seasons: during the period of increasing (March), maximum (June), decreasing (September) and minimum daylight hours (December). The concentration of 25-hydroxyvitamin D, serotonin, dopamine, adrenaline and noradrenaline in the blood were determined. Results. The annual dynamics of 25-hydroxyvitamin D level in the blood was established with its minimum content in the winter (December), followed by an increase in the vitamin concentration in the spring, the highest level during the period of maximum daylight hours (June) and a further decrease in the fall (September). During the period of minimum day length, the smallest proportion of people (15 %) with optimal 25-hydroxyvitamin D concentration is observed, while more than half of women have insufficient level, and a quarter have vitamin D deficiency. Serotonin level decreased from spring to winter. The peak of dopamine concentration was recorded in the summer; the minimum content was recorded in the autumn. The minimum concentration of adrenaline and noradrenaline is noted in the spring; the maximum levels are in the winter. Conclusions. The most critical season for 25-hydroxyvitamin D content in women blood is the minimum duration of daylight hours’ period (December), while the more favorable season can be attributed to the maximum duration period (June) and a decrease in the duration of daylight hours (September). The annual 25-hydroxyvitamin D dynamics and serotonin levels have similar features, and seasonal changes in the adrenaline and noradrenaline concentration are in the opposite direction.

Background: Algae play important roles in urban river ecosystems and are the cornerstones of most water quality monitoring programs. Thus, a better understanding of algal community dynamics is needed to support sustainable management of water resources in urban rivers. Results: In this study, we quantified the seasonal variations in planktonic and periphytic algal community structure in the highly urban Fenhe River and identified environmental factors affecting algal community structure and diversity. We monitored planktonic (drifting) and periphytic (attached) algal communities in the Taiyuan section of the Fenhe River over one year. The results indicated that Cyanophyta was the dominant phylum in both communities, followed by Bacillariophyta and Chlorophyta. Significant differences were observed in the composition of the planktonic and periphytic algal communities. In particular, the periphytic algal community was more diverse than the planktonic community. Water temperature and pH were the main environmental factors affecting planktonic and periphytic algal community structure, respectively, while nutrients were the most significant factor affecting planktonic and periphytic algal diversity. Ecological modeling indicated that the variations in the algal communities of the Fenhe River are mainly driven by stochastic processes. A co-occurrence network developed for the communities displayed positive interactions between the planktonic and periphytic algae. Conclusions: These findings deepen our understanding of the seasonal interaction between planktonic and periphytic algae and the driving factors affecting community structure in the Fenhe River. They also provide a theoretical basis for the managing and protecting water resources in urban river ecosystems. [ABSTRACT FROM AUTHOR]

Our study focuses on the investigation of the ecological aspects (seasonal dynamics, height distribution, and preference of biotopes) of six species within the genus Panorpa (P. alpina Rambur, 1842, P. cognata Rambur, 1842, P. communis Linnaeus, 1758, P. germanica Linnaeus, 1758, P. hybrida MacLachlan, 1882, and P. vulgaris Imhoff & Labram, 1845). The observed seasonal dynamics predominantly display a monovoltine nature. P. communis was active from the early days of May, with individuals persisting until the beginning of October. Conversely, P. vulgaris exhibits activity from the third decade of May to mid-September. P. hybrida manifests within a concise timeframe, observed from late May to late July. P. cognata demonstrates activity commencing in early May, with individuals observed until the end of September. Within forest environments, the highest population density of all species is concentrated at a height of 1.5 m above ground level, whereas the minimum population density is recorded at a height of 12 m above ground level. P. vulgaris demonstrates comparable abundance across heights ranging from 1.5 to 7.5 m, whereas P. hybrida exhibits uniform distribution solely at heights of 1.5 and 3.5 m. Furthermore, the abundance of P. communis surpasses that at other heights when observed at the height of 1.5 m. Panorpa specimens exhibit an absence in open ecosystems at heights of 8 and 10 m. The peak of population density for all species is consistently identified at heights of 2 and 4 m. The application of six diverse entomological methodologies leads to optimal outcomes. Our investigations reveal that P. communis, P. vulgaris, and P. hybrida display greater attraction to beer traps, while P. cognata exhibits a comparatively diminished propensity for such traps. P. cognata, in contrast, demonstrates a substantial presence in pan traps and pitfall traps. In Malaise traps, pan traps, and pitfall traps, five distinct species were captured, although with a species composition differing from alternative methods. To sum up, for the comprehensive study of Panorpa across an expansive geographical spectrum, it is judicious to integrate both net captures and the use of diverse trap types. In addition, it is necessary to explore all biotopes and tiers of the forest. [ABSTRACT FROM AUTHOR]

Inter-basin water transfer projects, such as the Yellow River to Qingdao Water Diversion Project (YQWD), are essential for addressing water scarcity, but impact local aquatic ecosystems. This study investigates the seasonal characteristics of eukaryotic microbial communities in the Jihongtan Reservoir, the main water-receiving body of YQWD, over a one-year period using 18S rDNA amplicon sequencing. The results showed that the eukaryotic microbial diversity did not exhibit significant seasonal variation (p > 0.05), but there was a notable variance in the community structure (p < 0.05). Arthropoda and Paracyclopina, representing the most dominant phylum and the most dominant genus, respectively, both exhibited the lowest abundance during the winter. The Chlorophyta, as the second-dominant phylum, demonstrates its higher abundance in the spring and winter. The Mantel test and PLS-PM (Partial Least Squares Path Modeling) revealed that water temperature (WT), dissolved oxygen (DO), and pH influenced the seasonal dynamic of eukaryotic microbial communities significantly, of which WT was the primary driving factor. In addition to environmental factors, water diversion is likely to be an important influencing factor. The results of the co-occurrence network and robustness suggested that the spring network is the most complex and exhibits the highest stability. Moreover, keystone taxa within networks have been identified, revealing that these key groups encompass both abundant and rare species, with specificity to different seasons. These insights are vital for understanding the seasonal variation of microbial communities in the Jihongtan Reservoir during ongoing water diversions. [ABSTRACT FROM AUTHOR]

BACKGROUND: The microbial community plays a crucial role in Chinese strong‐flavor baijiu (SFB) fermentation. However, the seasonal dynamics of the microbial community in the SFB fermentation system and its contribution to the unique flavor of SFB have not been fully elucidated. In this study, we investigated the seasonal dynamics of the microbial community through 16S rRNA and ITS gene sequencing. RESULTS: The results revealed significant temporal dynamics of microbial communities and environmental variables throughout the four seasons. The influence of seasons on fungal communities was found to be more significant than on bacterial communities. The diversity of bacteria was higher during the winter and summer, whereas fungal diversity was more prominent in summer and autumn. Stochastic processes maintained their dominance in microbial assembly throughout all four seasons but the significance of heterogeneous selection increased during summer for both bacteria and fungi, whereas homogeneous selection became more pronounced during winter for fungi. The pH and environmental temperature were important drivers of microbial community assembly across different seasons, primarily impacting the core genera responsible for the production of major volatile flavor compounds (VFCs), especially ethyl caproate. CONCLUSION: These findings provide new insights into the impact of seasons on microbial communities and hold promise for improving the quality‐control measures for SFB brewed in different seasons. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Seedling stage is the most important stage of plant development and plays a critical role in the forest regeneration. Species composition, seasonal dynamics and spatial distribution of the tree seedlings in the 20 hm² Ailaoshan forest dynamic plot were studied. The forest dynamic plot was built in a mid-mountain moist evergreen broad- leaved forest in Ailaoshan. Within the plot, 450 seedling quadrats of size 1m x 1m were established. Species composition, seasonal recruitment, seasonal mortality and spatial distribution of tree seedlings were investigated for four years (from 2019 to 2022). The results were as follows: (1) A total of 2 928 seedlings of 58 species were recorded, belonging to 42 genera and 26 families. There were 817 recruits of 47 species and 1 181 dead seedlings of 50 species. (2) The importance values of tree seedlings varied among different tree species across years. Symplocos ramosissima and Machilus bombycina were the dominant species, with importance values consistently in the Top 2 in four years, while the importance value of the pioneer species Viburnum cyclindricum declined continuously. (3) Significant differences in species richness, average seedling species richness in quadrat, species diversity (Shannon-Wiener index, Simpson index), seedling number, recruits, recruitment rate, mortality and mortality rate of tree seedlings were not found between different seasons. (4) The majority of species exhibited restricted distribution within the plot, only a few species displayed a broader distribution across the plot. Tree seedlings had higher species richness, density and diversity (Shannon-Wiener index and Simpson index) in the flat topography compared to the ridge and valley of the plot. In conclusion, there are not significant differences in species composition, recruitment and mortality of tree seedlings between different seasons. Topography influences the spatial distribution and diversity of tree seedlings. The study reveals the dynamics of recruitment and mortality of tree seedlings, and provides the theoretical reference for biodiversity conservation and forest management. [ABSTRACT FROM AUTHOR]

The authors studied the content of photosynthetic pigments and their ratio during the warm period of the year (May–October) and during the period with stable snow cover (April) in sphagnum moss Sphagnum papillosum Lindb. on an oligotrophic bog in Arkhangelsk oblast. The content of photosynthetic pigments decreased from May to July, reaching a minimum, and then increased again by autumn. The content of pigments in moss tissues under the snow was comparable to the July minimum. Based on the results of factor and cluster analyses, it was suggested that the S. papillosum pigment complex in the first half of the growing season is adapted to high insolation and a long photoperiod, which is reflected by such indicators as the chlorophyll a/b ratio and the proportion of chlorophylls in the light-harvesting complex. In addition, during the growing season, the pigment complex apparently adapts to moisture conditions that depend on precipitation, especially during the period of summer decrease in the bog water level, which reflects the Chl/Car ratio. [ABSTRACT FROM AUTHOR]

Simple Summary: The red imported fire ant, Solenopsis invicta Buren, is a highly invasive species. Some native ants may show aggression towards S. invicta and thus suppress S. invicta invasion. However, only a few such native ants have been identified, and the available data are largely limited to their behaviors. Here, we not only observed the aggression levels between native ants and S. invicta, but also investigated their abundance in various habitats, the seasonal dynamics of their abundance, and their spatial distribution in habitats with S. invicta. Two ant species, Monomorium chinense and Nylanderia bourbonica, were demonstrated to show aggression towards S. invicta and could kill a large proportion of S. invicta. However, another ant, Iridomyrmex anceps, did not show aggression. M. chinense and N. bourbonica are more abundant in green belts (e.g., lawns) and grasslands relative to woodland and farmland. Their abundance is quite low in the early months of the year but increases in later parts of the season. M. chinense and N. bourbonica are restricted to marginal habitats, but after control of S. invicta, they can rebound rapidly within a few weeks. M. chinense and N. bourbonica have the potential to suppress S. invicta invasion in some habitats. Native ants have long been considered for their potential to suppress the red imported fire ant, Solenopsis invicta Buren (Hymenoptera: Formicidae), a highly invasive and destructive species. However, the knowledge in this field is limited to behavioral observations of a few related native ants. In this study, by setting up a series of ant combinations of three native ants, i.e., Monomorium chinense Santschi, the robust crazy ant Nylanderia bourbonica Forel, and Iridomyrmex anceps Roger, with S. invicta, we observed the aggression levels and mortality rates. Using baited vials, we also investigated the abundance of native ants in four types of habitats in Eastern China that are preferred by S. invicta (woodland, green belts on roadsides, grassland, and farmland), as well as their seasonal abundance when co-existing with S. invicta and their spatial distribution before and after control of S. invicta. We found that M. chinense and N. bourbonica show a degree of aggression towards S. invicta and can kill substantial proportions of S. invicta under laboratory conditions, but I. anceps does not. Both M. chinense and N. bourbonica can occur in each type of habitat investigated and are more abundant in green belts (particularly lawns with turf) and grasslands relative to other habitats. In grasslands with S. invicta, M. chinense maintained a low density before early July; however, its abundance increased thereafter and reached a peak in September. N. bourbonica also had a low density early in the season and increased steadily from April. Its abundance began to decrease substantially from November. In grasslands invaded by S. invicta, both M. chinense and N. bourbonica were restricted to sites close to the margins before S. invicta was controlled; however, they spread to a larger range within a few weeks after control of S. invicta. In conclusion, M. chinense and N. bourbonica have the potential to suppress S. invicta invasion in habitats that are abundant with these two native ants. [ABSTRACT FROM AUTHOR]

Nonstructural carbohydrates (NSC) are essential for tree growth and adaptation, yet our understanding of the seasonal storage and mobilization dynamics of whole-tree NSC is still limited, especially when tree functional types are involved. Here, Quercus acutissima Carruth. and Pinus massoniana Lamb, with distinct life-history traits (i.e. a deciduous broadleaf species vs an evergreen coniferous species), were studied to assess the size and seasonal fluctuations of organ and whole-tree NSC pools with a focus on comparing differences in carbon resource mobilization patterns between the two species. We sampled the organs (leaf, branch, stem and root) of the target trees repeatedly over four seasons of the year. Then, NSC concentrations in each organ were paired with biomass estimates from the allometric model to generate whole-tree NSC pools. The seasonal dynamics of the whole-tree NSC of Q. acutissima and P. massoniana reached the peak in autumn and summer, respectively. The starch pools of the two species were supplemented in the growing season while the soluble sugar pools were the largest in the dormant season. Seasonal dynamics of organ-level NSC concentrations and pools were affected by organ type and tree species, with above-ground organs generally increasing during the growing season and P. massoniana roots decreasing during the growing season. In addition, the whole-tree NSC pools of P. massoniana were larger but Q. acutissima showed larger seasonal fluctuations, indicating that larger storage was not associated with more pronounced seasonal fluctuations. We also found that the branch and root were the most dynamic organs of Q. acutissima and P. massoniana , respectively, and were the major suppliers of NSC to support tree growth activities. These results provide fundamental insights into the dynamics and mobilization patterns of NSC at the whole-tree level, and have important implications for investigating environmental adaptions of different tree functional types. [ABSTRACT FROM AUTHOR]

Although wild bird rehabilitation facilities are important for the conservation of wild species, individuals may be kept within the facilities for long periods, consequently posing a risk for the bird to be infected with pathogens to which they are not naturally exposed. In turn, novel pathogens may be introduced through rescued migratory species. Avian malaria and West Nile fever are important avian diseases transmitted by mosquitoes. To understand the transmission dynamics of such diseases at rehabilitation facilities, the ecology of vector mosquitoes, including species composition, seasonality, and feeding behaviors, were explored. Mosquitoes were collected at a wild bird rehabilitation facility and wildlife sanctuary in Japan from 2019 to 2020 using mouth aspirators, sweep nets, and light traps. A total of 2,819 mosquitoes of 6 species were captured, all of which are potential vectors of avian diseases. Culex pipiens pallens and Cx. pipiens form molestus were the dominant species (82.9% of all collected mosquitoes). Density and seasonality differed between sampling locations, presumably because of differences in mosquito behaviors including feeding preferences and responses to climatic factors. Blood-fed Culex mosquitoes fed solely on birds, and many mosquito species are thought to have fed on birds within the facility. Particularly, Cx. pipiens group probably fed on both rescued and free-living birds. The rehabilitation facility may be an important site for the introduction and spread of pathogens because 1) numerous mosquitoes inhabit the hospital and its surroundings; 2) blood-fed mosquitoes are caught within the hospital; 3) there is direct contact between birds and mosquitoes; 4) both birds within the hospital and wild birds are fed upon. Furthermore, blood-fed Cx. pipiens form molestus were observed in the winter, suggesting that pathogens might be transmitted even during the winter when other mosquito species are inactive. [ABSTRACT FROM AUTHOR]

IntroductionScutellaria barbata D. Don is a widely cultivated Chinese herbal medicine known for its medicinal properties. However, differences in the spatial distribution of metabolites, accumulation patterns of flavonoids, and pharmacological activities between the aerial parts and roots of S. barbata still remain unclear, posing challenges for its standardized cultivation and quality control. This study aimed to elucidate the quality differences between these plant parts and clarify their seasonal variations.MethodsThe chemical profiles were qualitatively analyzed by UPLC-QTOF-MS/MS. The accumulation patterns of total flavonoids, scutellarin and baicalin in different parts of S. barbata were quantitatively analyzed by UV and HPLC respectively. The differences of pharmacological efficacy were evaluated by antioxidant assays and CCK-8 assay.ResultsIn this research, there were 46 compounds identified in S. barbata that included 44 flavonoids. The aerial parts primarily accumulate flavonoids with 4′-hydroxyl group, while the root mainly accumulate flavonoids without this group. Additionally, the accumulation and variation of flavonoid components were seasonally dependent, with the aerial parts reaching peak content in spring during vigorous vegetative growth and the roots accumulating most flavonoids in autumn. The extracts from both parts exhibited antioxidant activity and inhibitory effects on cancer cell proliferation, with notable differences between them.DiscussionThis study provides valuable insights into the quality differences and seasonal dynamics of the different parts of S. barbata, offering a reference for standardized harvesting and quality control.

Background. There is reason suppose that the concentration of photosynthetic pigments in sphagnum mosses, as in vascular plants, changes throughout the year and varies from species to species. Moreover, hollow sphagnum species have a higher growth and photosynthesis rate than ridge sphagnum species, which suggests the presence of differences in the pigment complex of species from different habitats. Purpose. Evaluation of quantitative changes in the pigment complex of the sphagnum mosses growing in different microclimatic conditions within oligotrophic bogs during the growing season at high latitudes. Materials and methods. The content of photosynthetic pigments in the three Sphagnum species growing in oligotrophic conditions was determined using the photometric method in an acetone extract once a month from May to October. The study was carried out for S. fuscum and S. lindbergii in 2021-2022, and for S. angustifolium only in 2022. Statistical data processing was carried out in Microsoft Excel 2010 and SPSS Statistics 11. Results. Seasonal and interannual variability in the content of chlorophylls, carotenoids, and their ratios was revealed for the studied sphagnum species. The pigment complex of S. lindbergii and S. angustifolium during the growing season is influenced by the bog water level and air temperature. Changes in the pigment complex of S. fuscum are associated with the amount of precipitation. Conclusion. Apparently, the seasonal and interannual dynamics of the pigment complex of sphagnum mosses is species-specific, but to further verify this statement it is necessary to study other species of sphagnum mosses from the same habitats, since the dynamics may be associated not so much with a peculiar species, but with the ecological conditions of the habitat.

City color, serving as a pivotal element within the urban landscape, has garnered significant scholarly attention. Numerous cities have diligently instituted city color planning initiatives to enhance urban landscapes and cultivate city images. The color preference of citizens serves as a crucial foundation for the systematic development of city color planning. Nevertheless, the dynamic aspect of city color preferences is frequently neglected in previous research. Therefore, this article examined seasonal variations in city color preferences using Busan Metropolitan City, South Korea, as an illustrative case. Data collected through a questionnaire survey underwent statistical analyses, including the chi-square test, Wilcoxon rank sum test, and multiple logistic regression, to investigate the influence of seasons on city color preference. The findings revealed that seasons primarily impact the hue preferences in city colors, rather than brightness and chroma preferences. Furthermore, sex and age factors were introduced, and the Cochran–Mantel–Haenszel (CMH) test was employed to identify demographic groups exhibiting seasonal variations in city color preferences. The analysis disclosed noteworthy seasonal disparities in city color preference, particularly among middle-aged and elderly males, who exhibited a significant decrease in preference for yellow and a notable increase in preference for green during winter compared to summer. The outcomes of this study provide valuable insights for informing city color planning. Additionally, the distinctive city color preferences observed among different demographic groups can be effectively applied in urban regeneration initiatives, thereby contributing to human well-being.

[Objective] To reveal the vertical distribution differences of soil nitrogen components (total nitrogen, hydrolyzed nitrogen, ammonium nitrogen, nitrate nitrogen) in Liziping National Nature Reserve in Sichuan Province and their relationships with physicochemical factors. [Methods] In March, June, September and December 2022, the vertical variation characteristics of soil nitrogen components and physicochemical factors at altitudes of 1 800 m, 2 100 m, 2 400 m and 2 700 m in Liziping, Sichuan Province were determined and analyzed, and the relationship between environmental factors and nitrogen components and their seasonal differences were analyzed by multivariate analysis of variance and redundancy analysis. [Results] (1) Altitude, season and their interaction had significant effects on soil nitrogen composition, and in March, June, September and December the ammonium nitrogen content was 2 100 m>2 400 m>1 800 m>2 700 m above sea level, and the nitrate nitrogen content was 2 400 m>2 100 m>2 700 m>1 800 m above sea level, and the gradient increased over the month, the contents of total nitrogen and nitrate nitrogen showed a trend of increasing first, with the maximum content of total nitrogen and nitrate nitrogen being 1.25 g/kg and 8.26 mg/kg, respectively, in December, and the maximum content of hydrolyzed nitrogen and ammonium nitrogen in March being 185.14 mg/kg and 5.80 mg/kg respectively. The variation of total nitrogen, hydrolyzed nitrogen, ammonium nitrogen and nitrate nitrogen along the soil layer was consistent, and formed a “V” shape. (2) The vertical variation characteristics between physicochemical factors and nitrogen components in different seasons and altitudes were significantly different, and the contents of total phosphorus, available phosphorus and available potassium increased first and then decreased along the depth of soil layer. (3) Seasonal differences in the key factors affecting soil nitrogen composition, organic matter, non-capillary porosity, available potassium, total phosphorus, available phosphorus and capillary porosity in March and December, and organic matter, total potassium and capillary porosity, total phosphorus and available potassium in June and September. [Conclusion] This study provides a specific production practice basis for the response mechanism of soil nutrients to altitude and season and the comprehensive management of ecological conservation in nature reserve.

In this study, we investigated zooplankton composition and seasonal dynamics, as well as the influence of selected environmental factors on the zooplankton community in three ports on the Polish Baltic coast: Władysławowo, Gdynia and Gdańsk. Our aim was to determine whether harbours’ heavy traffic, chemical pollution and physical disturbances affect the zooplankton community, and whether new nonindigenous planktonic species occur in these habitats. Forty three zooplankton taxa were found in all three ports; however, it is important to note that no new nonindigenous species were observed in the port basins. The most influential environmental factors affecting the zooplankton community were: seawater temperature (17% of explained zooplankton variability) and transparency (4%), which were related to seasonal changes. Acartia spp. (although of different development stages) was the dominant taxon during the study, and the examined ports/seasons differed in the presence and proportions of less abundant taxa: the autumn and winter assemblages were dominated by Acartia spp. nauplii, the spring assemblage by numerous Polychaeta larvae, while Cirripedia nauplii and early development stages of Eurytemora affinis were particularly abundant in summer. In addition, changes in salinity (2% explained variability) had a particular impact on the zooplankton community and especially on the assemblage of Gdańsk Port, which was influenced by freshwater inflow from the Motława and Dead Vistula rivers. Our study has clearly shown that, despite severe physical and chemical disturbances in all studied ports, the composition and seasonal dynamics of the zooplankton community were similar to those of the Gulf of Gdańsk outside the ports.

BackgroundViruses impact nearly all organisms on Earth, including microbial communities and their associated biogeochemical processes. In soils, highly diverse viral communities have been identified, with a global distribution seemingly driven by multiple biotic and abiotic factors, especially soil temperature and moisture. However, our current understanding of the stability of soil viral communities across time and their response to strong seasonal changes in environmental parameters remains limited. Here, we investigated the diversity and activity of environmental soil DNA and RNA viruses, focusing especially on bacteriophages, across dynamics' seasonal changes in a snow-dominated mountainous watershed by examining paired metagenomes and metatranscriptomes.ResultsWe identified a large number of DNA and RNA viruses taxonomically divergent from existing environmental viruses, including a significant proportion of fungal RNA viruses, and a large and unsuspected diversity of positive single-stranded RNA phages (Leviviricetes), highlighting the under-characterization of the global soil virosphere. Among these, we were able to distinguish subsets of active DNA and RNA phages that changed across seasons, consistent with a "seed-bank" viral community structure in which new phage activity, for example, replication and host lysis, is sequentially triggered by changes in environmental conditions. At the population level, we further identified virus-host dynamics matching two existing ecological models: "Kill-The-Winner" which proposes that lytic phages are actively infecting abundant bacteria, and "Piggyback-The-Persistent" which argues that when the host is growing slowly, it is more beneficial to remain in a dormant state. The former was associated with summer months of high and rapid microbial activity, and the latter with winter months of limited and slow host growth.ConclusionTaken together, these results suggest that the high diversity of viruses in soils is likely associated with a broad range of host interaction types each adapted to specific host ecological strategies and environmental conditions. As our understanding of how environmental and host factors drive viral activity in soil ecosystems progresses, integrating these viral impacts in complex natural microbiome models will be key to accurately predict ecosystem biogeochemistry. Video Abstract.

Plant parasitic nematodes (PPNs) pose a significant threat to the successful cultivation of grapevines globally. Abiotic parameters such as temperature, moisture and pH critically influence nematode population growth. Ecological investigation was conducted on three grapevine cultivars (Sahibi, Hussaini and Thompson) in Kashmir, India, from January 2021 to December 2022. The population dynamics of the identified PPNs around the grapevine rhizosphere were studied in relation to various factors. Nematode abundance peaked during the warm months of the summer season and dipped during winter. Soil and air temperatures positively correlated with the abundance of nematodes; however, soil moisture and rainfall showed a negative correlation. This study underscores the critical role of environmental factors on the population dynamics of plant parasitic nematodes, with temperature being an important influential factor. Effective nematode management in grapevine cultivation requires a thorough understanding of these dynamics to mitigate the impact of these parasites. [ABSTRACT FROM AUTHOR]

To control the growth of CO2 emissions and achieve the goal of carbon peaking, this study carried out a detailed spatio-temporal analysis of carbon emissions in major cities of China on a city-wide and seasonal scale, used carbon emissions as an indicator to explore the impact of COVID-19 on human activities, and thereby studied the urban resilience of different cities. Our research re-vealed that (i) the seasonal patterns of CO2 emissions in major cities of China could be divided into four types: Long High, Summer High, Winter High, and Fluctuations, which was highly related to the power and industrial sectors. (ii) The annual trends, which were strongly affected by the pan-demic, could be divided into four types: Little Impact, First Impact, Second Impact, and Both Impact. (iii) The recovery speed of CO2 emissions reflected urban resilience. Cities with higher levels of de-velopment had a stronger resistance to the pandemic, but a slower recovery speed. Studying the changes in CO2 emissions and their causes can help to make timely policy adjustments during the economic recovery period after the end of the pandemic, provide more references to urban resilience construction, and provide experience for future responses to large-scale emergencies. [ABSTRACT FROM AUTHOR]

The aim of this study was to assess the deposition rates (Td) of mineral aeolian sediments in a forest patch in the semiarid Pampas agroecosystem and to analyze the seasonal variability of such deposition. The average Td was 520.15 kg ha-1 year-1 with high interannual variability. In spring-summer, Td was higher than in autumn-winter. Air temperature and average maximum wind speed influenced Td more significantly. However, the soil cover and management of the agricultural fields surrounding the forest would determine the production of sediment from wind erosion and consequent deposition within the forest. These results show the importance of maintaining forest patches within the agricultural matrix in the semi-arid environment, since they retain eolian sediments that would eventually be deposited on the forest soil, minimizing the negative impacts of wind erosion processes on these ecosystems. [ABSTRACT FROM AUTHOR]

Using the static chamber–gas chromatography method, this study investigates the flux characteristics of CO2, CH4, and N2O in the soils of three typical island-like forests in the Sanjiang Plain during the growing season (May to September), as well as their relationships with environmental factors. The results indicate that the soils of the Broadleaf mixed forest, Quercus mongolica forest, and Betula platyphylla forest act as emission sources for CO2 and N2O, with average fluxes of 433.92, 452.41, and 358.17 μg·m−2·h−1 for CO2 and 12.48, 13.02, and 10.51 μg·m−2·h−1 for N2O, respectively. The differences among forest types are not significant. All three forest types serve as sinks for CH4, with average fluxes of −22.52, −23.29, and −0.76 μg·m−2·h−1. The Betula platyphylla forest has a significantly weaker absorption intensity compared to the other types (p < 0.01). The measured environmental factors collectively explain 66.58% of the variability in greenhouse gas fluxes in the island-like forests, with soil temperature, soil moisture, and total nitrogen content being the main influencing factors in the region. Rising temperatures favor the emission of CO2 and N2O and the absorption of CH4 in all three forest types. Increased soil moisture inhibits the absorption of CH4 in the Broadleaf mixed forest and Quercus mongolica forest, while higher levels of alkali-hydrolyzed nitrogen enhance the N2O flux in the Quercus mongolica forest. Soil organic carbon and soil pH significantly influence only the greenhouse gas fluxes of the Betula platyphylla forest. [ABSTRACT FROM AUTHOR]

The study investigates the nutritional status and feed resources for indigenous Ladakhi cattle in Ladakh's cold arid region amid changing climate scenarios. It evaluates seasonal dry matter (DM) consumption, crude protein (CP) intake, and total digestible nutrient intake, revealing the cattle's resilience to extreme conditions. Key findings show a 46.93% deficiency in DM during winter, indicating significant feed scarcity. CP deficiency averages 33.04% in summer, improving to 26.23% in winter with Lucerne hay. The study highlights regional differences, with Diskit showing higher feed intake due to its extensive agricultural area, surpassing Panamic and Chuchot by over 50% in DM intake during both summer and winter. These findings emphasize the need for innovative agricultural and feed preservation methods to enhance livestock sustainability in Ladakh. The results have important implications for policy and adaptive strategies to support livestock-dependent communities amid global climate changes. [ABSTRACT FROM AUTHOR]

From April of 2022 to March of 2023,we investigated the bird diversity in Qingtian Turtle Provincial Nature Reserve by using the transect method. A total of 76 bird species of 36 families, 12 orders were recorded, including 7 species of national second-class key protected birds and 4 species of near threatened (NT) species. In terms of residence types, there were 49 species of resident birds, 16 species of winter migratory birds, 8 species of summer migratory birds and 3 species of traveling birds. In terms of faunal types, there were 44 species of oriental birds, 29 species of palaearctic birds, and 3 species of widely distributed birds. The bird ecotype in reserve was dominated by the songbirds, 45 species were recorded. Shannon Wiener diversity index, Simpson dominance index and Pielou evenness index in the winter were the largest,and Margalef richness index in the autumn was the largest. The four indices in the summer were all the smallest. This study systematically analyzed the diversity characteristics of bird communities in the reserve, which provided scientific references for further protection and management in the reserve. [ABSTRACT FROM AUTHOR]

Phyllosphere microbes residing on plant leaf surfaces for maintaining plant health have gained increasing recognition. However, in desert ecosystems, knowledge about the variety, composition, and coexistence patterns of microbial communities in the phyllosphere remains limited. This study, conducted across three basins (Turpan-TLF, Tarim-CL, and Dzungaria-MSW) and three seasons (spring, summer, and autumn) in Xinjiang, China, aimed to explore the diversity and composition of microbial communities in the phyllosphere, encompassing both bacteria and fungi in Alhagi sparsifolia. We also investigated the co-occurrence patterns, influencing factors, and underlying mechanisms driving these dynamics. Results indicate that phyllosphere bacteria exhibited lower diversity indices (ACE, Shannon, Simpson, Fisher phylogenetic diversity, and Richness) in spring compared to summer and autumn, while the Goods Coverage Index (GCI) was higher in spring. Conversely, diversity indices and GCI of phyllosphere fungi showed an opposite trend. Interestingly, the lowest level of multi-functionality and niche width in phyllosphere bacteria occurred in spring, while the highest level was observed in phyllosphere fungi. Furthermore, the study revealed that no significant differences in multi-functionality were found among the regions (CL, MSW, and TLF). Network analysis highlighted that during spring, phyllosphere bacteria exhibited the lowest number of nodes, edges, and average degree, while phyllosphere fungi had the highest. Surprisingly, the multi-functionality of both phyllosphere bacteria and fungi showed no significant correlation with climatic and environmental factors but displayed a significant association with the morphological characteristics and physicochemical properties of leaves. Structural Equation Model indicated that the morphological characteristics of leaves significantly influenced the multifunctionality of phyllosphere bacteria and fungi. However, the indirect and total effects of climate on multi-functionality were greater than the effects of physicochemical properties and morphological characteristics of leaves. These findings offer new insights into leaf phyllosphere microbial community structure, laying a theoretical foundation for vegetation restoration and rational plant resource utilization in desert ecosystems. [ABSTRACT FROM AUTHOR]

The ontomorphogenesis and generative shoot development in Nelumbo komarovii Grossh. were studied. The stages of embryo formation and pollen grain measurement are described. Pollen grain size ranges from 49 to 51 µm. Plants are characterized by the formation of fruits with up to 43 seeds. The embryo development, including the proembryo and embryo stages, is similar to that of other Nelumbo species. During the first year of life, Nelumbo komarovii successively undergoes four phases of morphogenesis: the primary (main) shoot, systems of "main shoot" and anchorage shoots, clump, and tuberous structure. During the second year of life, N. komarovii passes through three phases of development: vegetative assimilating shoot, vegetative-generative shoot, and tuberous structure. The plant is characterized by a monopodial main axis, each growth consists of a rosette and a stolon. At the end of the growing season, shoot swelling and the formation of tuberous structures were observed at the ends of both the main and lateral shoots. As a result of the decay of the shoot regions preceding the tuberous structures, vegetative propagation occurs. The annual and seasonal dynamics of the N. komarovii population in the conditions of the suburbs of Vladivostok and the structure of the underwater parts of plagiotropic shoots and their changes during the growing season are characterized for the first time. It is difficult to trace the end of ontogenesis in N. komarovii due to the high degree of vegetative propagation and the vegetative mobility of the plants. Different points of view on the taxonomy of Nelumbo are discussed. [ABSTRACT FROM AUTHOR]

Exploring the effects of environmental factors and plant physiological processes on plant nutrient stoichiometry is of great significance to understanding how wetland vegetation distributes and maintains function. However, we have a limited understanding of how the combination of plant communities and seasonality with soil physicochemical properties affects nutrient stoichiometry in wetland plants. In this study, we examined these factors in Carex thunbergii and soil across four types of plant communities dominant in the riparian zone of Shengjin Lake during the non−flooding periods of December 2020 and March 2021. In winter, the total foliar C, N, and P concentrations decreased along with an increase in plant coverage, which did not differ in spring. The C, N, C: P, and N: P of foliage significantly increased over the season, while soil C, N, C: P, and N: P significantly decreased over the season. Both in winter and spring, soil C and soil N decreased along with the increase of plant coverage. Our results suggest that both plant community and soil physicochemical properties have a significant influence on plant nutrient stoichiometry. This study improves our understanding of the seasonal dynamics of plant nutrients under different communities and soil physicochemical properties. [ABSTRACT FROM AUTHOR]

Arbuscular mycorrhizal fungi (AMF) live simultaneously inside and outside of host plant roots for a functional mycorrhizal symbiosis. Still, the year-round dynamics and relationships between soil properties and AMF communities of trees in forest ecosystems remain unclear. We collected paired root and soil samples of the same Cryptomeria japonica trees at two forest sites (five trees at each site) every 2 months over a year. Total DNA was extracted from roots and soil separately and soil physicochemical properties were measured. With Illumina's next-generation amplicon sequencing targeting the small subunit of fungal ribosomal DNA, we clarified seasonal dynamics of soil properties and AMF communities. Soil pH and total phosphorus showed significant seasonality while total carbon, nitrogen, and C/N did not. Only pH was a good predictor of the composition and dynamics of the AMF community. The total AMF community (roots + soil) showed significant seasonality because of variation from May to September. Root and soil AMF communities were steady year-round, however, with similar species richness but contained significantly different AMF assemblages in any sampling month. Despite the weak seasonality in the communities, the top two dominant OTUs showed significant but different shifts between roots and soils across seasons with strong antagonistic relationships. In conclusion, few dominant AMF taxa are dynamically shifting between the roots and soils of C. japonica to respond to seasonal and phenological variations in their microhabitats. AMF inhabiting forest ecosystems may have high environmental plasticity to sustain a functional symbiosis regardless of seasonal variations that occur in the soil. [ABSTRACT FROM AUTHOR]

The second part of the research presents an analysis of daily average data on cloudiness (cloud cover) in the Fergana Valley based on an 8-point scale for the period of 2000–2022. The main focus is on the number of clear, partly cloudy and cloudy days, as well as the number of days without sun. It was revealed that the largest number of clear days per year was recorded at the Boz weather station (168 days), while the smallest was in Fergana (112 days). As for partly cloudy days, the maximum number was recorded at Yubileinaya weather station (81 days). The maximum number of cloudy days was observed at the Fergana weather station (186 days). Based on the results and the annual dynamics of clear days, the locations in the region of Boz and Kokand weather stations appear to be the most suitable for installing solar power plants due to their potential for the efficient use of sunlight. Also, despite of the summer potential, in winter the number of clear days decreases, which can affect the performance of solar power plants. This is especially true for the Fergana weather station, where the number of cloudy days in December and January can reach 23. On average, the Andijan, Boz, Yubileinaya, Pap, Kokand and Kuva weather stations, observe 3–4 consecutive days without sun per year. At the Fergana weather station, this value is 4–6 days. The obtained results may be useful for the further sun energetic development in this region. [ABSTRACT FROM AUTHOR]

This study aims to explore how the environment affects the variation and trade-offs of anatomical traits in shrub plants, contributing to a deeper understanding of plant survival strategies and mechanisms of adaptation to the environment. The dominant shrub species Corylus mandshurica in the broad-leaved Korean pine (Pinus koraiensis) forest was selected as the research subject. Current-year twigs and leaves of C. mandshurica were collected in spring (May), summer (July), and autumn (September). Anatomical traits, including non-vascular column proportion (NVP), vascular column proportion (VP), phloem proportion (PP), and xylem proportion (XP), were measured for twigs, lower part of petioles, upper part of petioles, and leaf veins. We found that (1) Compared with seasons, organ type explained most of the variation in the four traits (NVP = 96 %, VP = 87 %, PP = 81 %, XP = 76 %). Lower part of petioles served as the turning point in the variation trend of tissue proportions in cross-sectional structure along the sequence of twigs, lower part of petioles, upper part of petioles, and leaf veins. (2) In spring, C. mandshurica exhibits higher NVP but lower VP and PP, while the results in summer and autumn are opposite to those in spring. Among different organs, twigs show lower NVP but higher VP and XP; whereas petioles and leaf veins show the opposite pattern. (3) Both hydrothermal conditions (monthly precipitation and mean monthly temperature) and light (canopy openness and total transmitted radiation) were the dominant environmental factors influencing anatomical trait variation. In different seasons, the response of NVP and VP in C. mandshurica twigs to dominant environmental factors was opposite to that of lower part of petioles, upper part of petioles, and leaf veins. The response of cross-sectional anatomical traits of current-year twigs, petioles, and leaf veins in C. mandshurica to seasonal changes exhibits distinct characteristics. Furthermore, twigs, petioles, and leaf veins demonstrate distinct survival strategies. Future research should focus on the variation of traits in different plant organs and their connecting parts.

ABSTRACT Seasonal fluctuations profoundly affect marine microeukaryotic plankton composition and metabolism, but accurately tracking these changes has been a long-standing challenge. In this study, we present a year-long metatranscriptomic data set from the Southern Bight of the North Sea, shedding light on the seasonal dynamics in temperate plankton ecosystems. We observe distinct shifts in active plankton species and their metabolic processes in response to seasonal changes. We characterized the metabolic signatures of different seasonal phases in detail, thereby revealing the metabolic versatility of dinoflagellates, the heterotrophic dietary strategy of Phaeocystis during its late-stage blooms, and stark variations in summer and fall diatom abundance and metabolic activity across nearby sampling stations. Our data illuminate the varied contributions of microeukaryotic taxa to biomass production and nutrient cycling at different times of the year and allow delineation of their ecological niches.IMPORTANCEEcosystem composition and metabolic functions of temperate marine microeukaryote plankton are strongly influenced by seasonal dynamics. Although monitoring of species composition of microeukaryotes has expanded recently, few methods also contain seasonally resolved information on ecosystem functioning. We generated a year-long spatially resolved metatranscriptomic data set to assess seasonal dynamics of microeukaryote species and their associated metabolic functions in the Southern Bight of the North Sea. Our study underscores the potential of metatranscriptomics as a powerful tool for advancing our understanding of marine ecosystem functionality and resilience in response to environmental changes, emphasizing its potential in continuous marine ecosystem monitoring to enhance our ecological understanding of the ocean's eukaryotic microbiome.

Information about the population structure, including the age and sex composition, growth characteristics, and diet of fish, is essential for the conservation and sustainable exploitation of fish stock. The burbot, Lota lota, is the only freshwater species of the family Lotidae in the Amur (Heilongjiang) River catchment located in northeastern China. Information on the biological characteristics and data on the population structure of this fish from the Amur River are scarce. To study these factors in burbot, Lota lota, in the Amur River of China, 749 specimens from four sampling areas were taken and analyzed in October 2022, January 2023, and May 2023. The ages of the sampled fish ranged from 1+ to 7+ years. The female/male ratio was 1.04:1, and body length and mass varied from 175 to 595 mm and 73.5 to 1958.7 g, respectively. The length–weight regression parameter b value was estimated as 2.80. The parameters of the von Bertalanffy growth model were L∞ = 596, K = 0.221, and t0 = −0.771 for all sampled fish; L∞ = 625, K = 0.208, and t0 = −0.756 for females; and L∞ = 584, K = 0.219, and t0 = −0.980 for males. The analysis of the stomach contents showed fish to be the major source of nutrition across all areas and sampling periods. In January, the secondary prey of burbots in the Huma reach of the upper Amur River was aquatic insect larvae, while, in the Tongjiang and Fuyuan reaches of the middle Amur River, the secondary prey was shrimp. The mean stomach fullness index and rate of empty stomachs differed with the sampling area, with the greatest proportion of empty stomachs observed in the Luobei reach of the middle Amur River, and the lowest in the Tongjiang and Fuyuan reaches. The mean stomach fullness index showed the opposite trend. In the Huma reach, the contributions of fish to the diet and the mean stomach fullness index were significantly higher in May than in October and January. The study provides the first detailed information on the population age and sex structure, growth patterns, and feeding ecology of burbots from the Amur River, China. The results will aid in formulating management strategies and regulations for local populations of burbots in the Amur River, China.

Soil microbial communitys responses to climate warming alter the global carbon cycle. In temperate ecosystems, soil microbial communities function along seasonal cycles. However, little is known about how the responses of soil microbial communities to warming vary when the season changes. In this study, we investigated the seasonal dynamics of soil bacterial community under experimental warming in a temperate tall-grass prairie ecosystem. Our results showed that warming significantly (p = 0.001) shifted community structure, such that the differences of microbial communities between warming and control plots increased nonlinearly (R 2 = 0.578, p = 0.021) from spring to winter. Also, warming significantly (p

Introduction: The phyllosphere of plants is inhabited by various microorganisms, which play a crucial role in plant physiological metabolism. Currently, there is limited research on the dynamic effects of species and seasons on plant phyllosphere microbial community diversity and microbial interactions. Methods: In this study, high-throughput sequencing technology was used to sequence the leaf surface parasitic microorganisms of five medicinal plants (Bupleurum chinense, Atractylodes lancea, Salvia miltiorrhiza, Astragalus membranaceus, and Lonicera japonica). Results: The results showed that bacteria and fungi clustered into 3,898 and 1,572 operational taxonomic units (OTUs), respectively. Compared to host species, seasons had a more significant impact on the a diversity of bacteria and fungi. The heterogeneity of phyllosphere microbial communities was greater in winter compared to summer. Key species analysis at the OTU level and Spearman correlation analysis demonstrated significant preferences in microbial interactions under plant and seasonal backgrounds. The network connections between bacterial and fungal communities significantly increased during seasonal transitions compared to connections with plants. Discussion: This study enhances our understanding of the composition and ecological roles of plant-associated microbial communities in small-scale agricultural environments. Additionally, it provides valuable insights for assessing the biodiversity of medicinal plants. [ABSTRACT FROM AUTHOR]

The work highlights the peculiarities of the seasonal activity of rove beetles that occur in different types of forest ecosystems in the mountain massif of Gorgan. The research territory covered three landscape-altitude zones, within which five types of forest ecosystems were identified: Scots pine and European cedar pine forests (subalpine zone), spruce-fir forests (upper forest zone), as well as mixed (spruce-fir-beech) and beech forests (lower forest belt). The collection of specimen material was carried out from 2017 to 2021 throughout the entire vegetation period, using Barber traps. During the research, representatives of 76 species of Staphylinidae belonging to 13 subfamilies were identified. The highest level of species richness is observed in the subfamilies Staphylininae, Tachyporinae, and Steninae. The highest number of species was recorded in beech forests (55 species), while the lowest was found in mountain pine forests (23 species) and European cedar pine forests (25 species). Specific species were found in each ecosystem, with only five species being common to all analyzed biocenosis: Atrecus longiceps, Philonthus decorus, Tasqius morsitans compressus, Stenus comma comma, Tachynus rufipes. The analysis of the seasonal dynamics of rove beetles demonstrates common patterns for groups in different types of forest ecosystems. Specifically, the highest activity levels of insects are observed during June-July, while the lowest ones occur in April and October. An exception is observed in the ecosystems of mountain pine and European cedar pine, where Staphylinidae are found from the second half of May until the end of August, and certain species can be found in the first half of September. Throughout the warm period of the year, multiple peaks of activity are observed in staphylinid communities. In the ravine forest, the peak of summer activity for mountain pines falls in the second decade of July, with three species predominating: Eusphalerum primulare, Omalium rugatum and Tasgius morsitans compressus. The autumn increase in activity is characterized by a much lesser degree of expression and the dominance of Paederus (Poedemorphus) littoralis littoralis and Tachyporus hypnorum. In the biocenosis of European cedar pine, are two summer peaks of rove beetles beetles: the first during the first decade of July and the second in the second decade of August. During the July peak Omalium rugatum, Eusphalerum primulare, and Oxyporus rufus rufus dominate, while during the August peak, Acidota crenata, Atrecus longiceps, and Lordithon trinotatus dominate. In the group of spruce-fir forests, the first peak of activity occurs in the summer, while the second peak occurs in autumn, with a relatively consistent decrease in activity between them. The dominant species include Eusphalerum primulare, Ocypus (Matidus) nitens nitens, Staphylinus caesereus caesereus and Tasgius (Rayachelia) morsitans compressus, Lordithon lunulatus. Staphylinid communities in mixed forests form two peaks of activity: spring and summer It is worth noting that the first two are pronounced and prolonged During the first peak, the most common are Ontholestes tesselatus, Tachyporus chrysomelinus, Anotylus sculptoratus, Philonthus decorus; the other ‒ Tasgius melanarius, Tachyporus chrysomelinus, Philonthus splendens, Philonthus rubripennis. Staphylinid communities in beech forests are also characterized by three peaks of activity, two of which are pronounced, and one (autumn) is insignificant. During these peaks Tasgius bicharicus, Staphylinus caesereus, Staphylnus erythropterus predominate, during the second peak Tasgius bicharicus, Nudobius lentus, Lordithon trinotatus and Abemus chloropterus dominate, Tachyporus chrysomelinus and Lordithon lunupatus predominate. [ABSTRACT FROM AUTHOR]

Microbial residue nitrogen can indicate soil quality and is crucial for soil nitrogen retention and supply. However, it is still unclear how the dynamic changes in soil microbial residue nitrogen affect crop nitrogen uptake in agricultural practice. Based on a long-term wheat-maize rotation experiment with different nitrogen application rates (150 kg N ha−1, 200 kg N ha−1, and 300 kg N ha−1), 15N-labeled nitrogen fertilizer was applied during the wheat season to track the dynamics of soil microbial residue nitrogen and its mediated fertilizer nitrogen. The results showed that nitrogen addition was beneficial to the accumulation of microbial residue nitrogen (mainly fungal microbial residue nitrogen). Its contribution rate to soil total nitrogen is 54.87–56.55%, and the fertilizer nitrogen allocated to it accounts for 27.10–47.50% of the remaining fertilizer nitrogen in the soil. Ultimately, 6.77–10.24% of the nitrogen fertilizer applied remained in the soil as microbial residue nitrogen. In addition, microbial residue nitrogen is mainly mineralized during the jointing and filling stages of wheat. In a word, the accumulation and mineralization of soil microbial residue nitrogen during the application of 200 kg N ha−1 better guaranteed the uptake of nitrogen by wheat, which provided a reliable basis for guiding farmland fertility improvement and nitrogen fertilizer reduction in the North China Plain. [ABSTRACT FROM AUTHOR]

The impact of different crop production systems was investigated on incidence of insect pests and their natural enemies, soil microflora and enzymatic activity, and quality of fruits produced in spring planted tomato at Ludhiana, Punjab, during 2017 to 2019. Production systems included conventional farming whereby indiscriminate and excessive use of agrochemicals is practiced, organic farming, and farming following Good Agricultural Practice (GAP) with IPM adoption. Higher Aphis gossypii and Helicoverpa armigera infestation was observed in organic fields followed by IPM and conventional fields. Aphid population showed a negative correlation with maximum and minimum temperature but a positive correlation with relative humidity, while the tomato fruit borer showed a positive correlation with maximum and minimum temperature but negative correlation with relative humidity and rainfall. The mean fruit yield in the farming system following IPM was maximum (50120 Kg ha-1) followed by conventional farmers' fields (408.1 q/ha) and organic fields (403.9 q/ha). The mean spider population under organic conditions (0.39-0.56) was significantly higher than that of IPM (0.26-0.36) and conventional farmers' fields (0.02-0.10). Soil samples from conventional fields revealed the presence of quinalphos and chlorpyriphos, while tomato fruit samples showed the presence of triazophos and mancozeb during 2017 and 2018. In 2017, the flavonoids and percent antioxidant activity in fruits from organic field were higher. The bacterial count in organic and IPM field soil increased from 5.4×107 and 4.9×107 CFU g-1 in 2017 to, respectively, 7.1×107 and 6.5×107 CFU g1 in 2019. The activity of alkaline phosphatase and urease was highest in organic fields. [ABSTRACT FROM AUTHOR]

Climate change is altering patterns of precipitation, cryosphere thaw, and land–ocean influxes, affecting understudied Arctic estuarine tidal flats. These transitional zones between terrestrial and marine systems are hotspots for biogeochemical cycling, often driven by microbial processes. We investigated surface sediment bacterial community composition and function from May to September along a river–intertidal–subtidal–fjord gradient. We paired metabarcoding of in situ communities with in vitro carbon-source utilization assays. Bacterial communities differed in space and time, alongside varying environmental conditions driven by local seasonal processes and riverine inputs, with salinity emerging as the dominant structuring factor. Terrestrial and riverine taxa were found throughout the system, likely transported with runoff. In vitro assays revealed sediment bacteria utilized a broader range of organic matter substrates when incubated in fresh and brackish water compared to marine water. These results highlight the importance of salinity for ecosystem processes in these dynamic tidal flats, with the highest potential for utilization of terrestrially derived organic matter likely limited to tidal flat areas (and times) where sediments are permeated by freshwater. Our results demonstrate that intertidal flats must be included in future studies on impacts of increased riverine discharge and transport of terrestrial organic matter on coastal carbon cycling in a warming Arctic. [ABSTRACT FROM AUTHOR]

This paper compiles the data regarding the first occurrence of Oithona davisae and O. atlantica in NW Spain, which is supported by morphological and molecular analysis. Additionally, we investigated the seasonal dynamics of the invasive O. davisae, revealing that its abundance is conditioned by upwelling-downwelling patterns in the Rías Baixas of Galicia. Temperature was the most correlated factor, with higher abundances in upwelling relaxation-downwelling events. More studies in long-term zooplankton dynamics and molecular analysis are needed to determine if O. davisae is displacing other native species of the same genus, such as O. atlantica, in Galician waters. [ABSTRACT FROM AUTHOR]