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Freshwater fish such as juvenile salmon often rely on dynamic and diverse habitats such as wetlands. Although juvenile salmon wetland use is well documented, their use of freshwater wetlands in large river networks that vary in isolation and connection is not well known. We studied juvenile coho salmon use of three wetland sites along the North Thompson River, British Columbia, Canada, from May 2021 to October 2023 to understand how seasonal variation in wetland connectivity and water quality (temperature and dissolved oxygen) influence juvenile coho salmon habitat use. We used monthly mark–recapture sampling to estimate juvenile coho salmon abundance and density. Seasonal abundance and growth of juvenile coho salmon in wetlands were intertwined with connectivity and abiotic conditions. Age-0 juvenile coho salmon were recruited to wetlands during high spring flows and used wetland habitats year-round. Periods of high density and low oxygen were associated with lower growth and abundance. Our study also provides information on the timing of juvenile coho salmon use of wetland habitats, which can be used to inform habitat managers of times of year that pose the greatest risk and benefits to these fish. [ABSTRACT FROM AUTHOR]

Monitoring zooplankton diversity and community dynamics is essential for understanding ecological processes within freshwater ecosystems. Environmental DNA (eDNA) has been increasingly employed in this field due to its efficiency and accuracy. However, its potential applications in freshwater ecosystems require further validation. In this study, we evaluated the performance of 18S rRNA and COI primers for freshwater zooplankton diversity monitoring and systematically compared the selected primers with the microscopy method in Qiandao Lake, China. Our results indicated that the COI primer marker (mlCOIintF/jgHCO2198) was more suitable for freshwater zooplankton diversity monitoring than 18S rRNA. The eDNA method identified a total of 102 species, whereas the microscopy method detected 111 species. Non-metric multidimensional scaling (NMDS) analysis and nonparametric multivariate statistical tests revealed that both abundance and biomass species compositions determined by microscopy differed significantly from those based on eDNA reads. Both methods detected significant seasonal changes in zooplankton community species composition, while eDNA provided a comprehensive view of the complex interactions within the community. Both methods indicate that rotifers are the primary group driving seasonal changes in the zooplankton community. The eDNA identified more environmental factors associated with seasonal changes in zooplankton communities than microscopy, including dissolved oxygen (DO), nephelometric turbidity unit (NTU), ammonia nitrogen (NH3-N), and total phosphorus (TP). The eDNA reads of rotifer and crustacean plankton increased linearly with their morphological abundance but not with biomass. Furthermore, combining morphological abundance and biomass as predictor variables for eDNA reads moderately enhanced the explanatory power compared to using them individually. Although eDNA cannot yet replace morphological methods, its efficiency and sensitivity make it a valuable complementary tool for zooplankton monitoring, with considerable potential for future applications. [ABSTRACT FROM AUTHOR]

Gross primary production (GPP) is a crucial indicator representing the absorption of atmospheric CO2 by vegetation. At present, the estimation of GPP by remote sensing is mainly based on leaf-related vegetation indexes and leaf-related biophysical parameter leaf area index (LAI), which are not completely synchronized in seasonality with GPP. In this study, we proposed chlorophyll content-based light use efficiency model (CC-LUE) to improve GPP estimates, as chlorophyll is the direct site of photosynthesis, and only the light absorbed by chlorophyll is used in the photosynthetic process. The CC-LUE model is constructed by establishing a linear correlation between satellite-derived canopy chlorophyll content (Chlcanopy) and FPAR. This method was calibrated and validated utilizing 7-d averaged in-situ GPP data from 14 eddy covariance flux towers covering deciduous broadleaf forest ecosystems across five different climate zones. Results showed a relatively robust seasonal consistency between Chlcanopy with GPP in deciduous broadleaf forests under different climatic conditions. The CC-LUE model explained 88% of the in-situ GPP seasonality for all validation site-year and 56.0% of in-situ GPP variations through the growing season, outperforming the three widely used LUE models (MODIS-GPP algorithm, Vegetation Photosynthesis Model (VPM), and the eddy covariance-light use efficiency model (EC-LUE)). Additionally, the CC-LUE model (RMSE = 0.50 g C/(m2·d)) significantly improved the underestimation of GPP during the growing season in semi-arid region, remarkably decreasing the root mean square error of averaged growing season GPP simulation and in-situ GPP by 75.4%, 73.4%, and 37.5%, compared with MOD17 (RMSE = 2.03 g C/(m2·d)), VPM (RMSE = 1.88 g C/(m2·d)), and EC-LUE (RMSE = 0.80 g C/(m2·d)) model. The chlorophyll-based method proved superior in capturing the seasonal variations of GPP in forest ecosystems, thereby providing the possibility of a more precise depiction of forest seasonal carbon uptake. [ABSTRACT FROM AUTHOR]

Non-structural carbohydrates (NSC) are important carbon pools in trees, and previous studies have mainly focused on the concentration of NSC in tree organs such as leaves, branches, trunk, and root, separately. However, the seasonality of the concentration of NSC in different organs among tree species in the subtropical forests is less known. In this study, we measured the seasonal dynamics of the concentration of NSC in four tree species (Nothotsuga longibracteata W. C. Cheng, Pinus kwangtungensis Chun ex Tsiang, Schima superba Gardn. et Champ, and Betula alnoides Buch.-Ham. Ex D.Don) in subtropical forests at organ levels including canopy, trunk, and root. The results showed that the concentration of NSC in conifer species was higher than that in broadleaf species. Also, the average concentration and range of the concentration of NSC were higher in the canopy than in other organs. The concentration of NSC decreased at the beginning of the growing season and increased at the end of the growing season for all species. Specifically, the concentration of NSC in tree species was significantly higher in the dry season than that in the wet season. Our results revealed the seasonal dynamics of NSC in different organs, which is beneficial to a better understanding of the growth strategies of different tree species in subtropical regions. [ABSTRACT FROM AUTHOR]

Storage reservoirs are crucial components of long-distance water diversion projects, where water diversion may lead to changes in microbial diversity and community structure. Seasonal variations also drive alterations in microbial communities. However, the way that microbes assemble under the combined effects of water diversion and seasonal variations in the storage reservoir has not been extensively studied. Jihongtan Reservoir is the terminal storage reservoir of the Yellow River to Qingdao Water Diversion Project (YQWD), which had an average annual water diversion period exceeding 290 days in recent years. In this study, 16S rDNA amplicon sequencing was used to investigate the seasonal dynamics and assembly of planktonic bacterial communities during the water diversion period in Jihongtan Reservoir. The results indicate that planktonic bacteria were able to maintain stable diversity across all four seasons, while the community structure underwent significant seasonal succession. Water temperature (WT) was found to be the primary driving environmental factor influencing the seasonal dynamic of planktonic bacterial communities. Co-occurrence network patterns of planktonic bacterial communities varied across different seasons, particularly in spring and winter. The spring network displayed the most complexity, showcasing the highest connectivity and greater stability. In contrast, the winter network was simpler, exhibiting lower local connectivity but higher global connectivity and lower stability. The analysis of the neutral community model and null model revealed that the relative importance of deterministic and stochastic processes in governing planktonic bacterial community assembly varies seasonally. Stochastic processes (dispersal limitation) are more prominent in spring, summer, and autumn, while deterministic processes (heterogeneous selection) play a greater role in winter. This study is essential for gaining a comprehensive understanding of the effects of water diversion projects and offers valuable references for the assessment of other similar projects. [ABSTRACT FROM AUTHOR]

Elucidating the effects of nitrogen and water addition on N2O dynamics is critical, as N2O is a key driver of climate change (including nitrogen deposition and shifting precipitation patterns) and stratospheric ozone depletion. The temperate steppe is a notable natural source of this potent greenhouse gas. This study uses field observations and soil sampling to investigate the seasonal pattern of N2O emissions in the temperate steppe of Inner Mongolia and the mechanism by which nitrogen and water additions, as two different types of factors, alter this seasonal pattern. It explores the regulatory roles of environmental factors, soil physicochemical properties, microbial community structure, and abundance of functional genes in influencing N2O emissions. These results indicate that the effects of nitrogen and water addition on N2O emission mechanisms vary throughout the growing season. Nitrogen application consistently increase N2O emissions. In contrast, water addition suppresses N2O emissions during the early growing season but promotes emissions during the peak and late growing seasons. In the early growing season, nitrogen addition primarily increased the dissolved organic nitrogen (DON) levels, which provided a matrix for nitrification and promoted N2O emissions. Meanwhile, water addition increased soil moisture, enhancing the abundance of the nosZ (nitrous oxide reductase) gene while reducing nitrate nitrogen ( N O 3 − -N) levels, as well as AOA (ammonia-oxidizing archaea) amoA and AOB (ammonia-oxidizing bacteria) amoA gene expression, thereby lowering N2O emissions. During the peak growing season, nitrogen's role in adjusting pH and ammonium nitrogen ( N H 4 + -N), along with amplifying AOB amoA, spiked N2O emissions. Water addition affects the balance between nitrification and denitrification by altering aerobic and anaerobic soil conditions, ultimately increasing N2O emissions by inhibiting nosZ. As the growing season waned and precipitation decreased, temperature also became a driver of N2O emissions. Structural equation modeling reveals that the impacts of nitrogen and water on N2O flux variations through nitrification and denitrification are more significant during the peak growing season. This research uncovers innovative insights into how nitrogen and water additions differently impact N2O dynamics across various stages of the growing season in the temperate steppe, providing a scientific basis for predicting and managing N2O emissions within these ecosystems. [ABSTRACT FROM AUTHOR]

Salmonellosis continues to be a global public health priority in which humans, livestock, and the contaminated environment interact with food to create complex interactions. Here, a new non-autonomous model is proposed to capture seasonal dynamics of Salmonella typhimurium transmission with key compartments that include humans, cattle, and bacteria in environmental and food sources. The model explores how bacterial growth, shedding, and ingestion rates, along with contamination pathways, determine disease dynamics. Some analytical derivations of the basic reproduction number ( R 0 ) and threshold conditions for disease persistence or extinction are derived by using the spectral radius of a linear operator associated with the monodromy matrix. Parameter estimation for the model was accomplished with the aid of Latin hypercube sampling and least squares methods on Salmonella outbreak data from Saudi Arabia ranging from 2018 to 2021. The model was able to conduct an analysis based on the estimated 0.606 value of R 0 , and this meant that the model was able to fit reasonably well for both the cumulative and the new individual case data, which in turn, suggests the disease is curable. Predictions indicate a gradual decline in the number of new cases, with stabilization anticipated at approximately 40,000 cumulative cases. Further simulations examined the dynamics of disease extinction and persistence based on R 0 . When R 0 is less than 1, the disease-free equilibrium is stable, resulting in the extinction of the disease. Conversely, when R 0 exceeds 1, the disease persists, exhibiting endemic characteristics with recurrent outbreaks. Sensitivity analysis identified several parameters as having a significant impact on the model's outcomes, specifically mortality and infection rates, along with decay rates. These findings highlight the critical importance of precise parameter estimation in understanding and controlling the transmission dynamics of Salmonella. Sensitivity indices and contour plots were employed to assess the impact of various parameters on the basic reproduction number and provide insights into the factors most influencing disease transmission. [ABSTRACT FROM AUTHOR]

Simple Summary: Urban beekeeping is growing in popularity, but it raises questions about the quality and safety of bee products and the health of bee colonies in city environments. While the safety of honey and other products has been well-studied, bees' health has received less attention. How does city life impact bees and their colonies? This study analyzed the strength of honeybee colonies and levels of vitellogenin, a protein vital for bee health and longevity, in worker bees from an urban apiary from May to August. Results were compared to those of a rural (agricultural) apiary. We found that urban bee colonies were more populous than rural areas. In addition, insects in urban colonies showed a unique mechanism: During periods of bee shortage in the colonies, the level of vitellogenins—proteins responsible for extending the bees' life—increased in the tissues of workers. This compensation mechanism may help explain the evolutionary success of social insects like honeybees in diverse environments. The study aimed to verify whether urban beekeeping affects the strength of the honeybee (Apis mellifera) colonies from urban apiaries and the variability of the crucial for their health and long-life protein—vitellogenins. For this purpose, honeybees were kept in two locations—in a city apiary on a roof in the city center and in agricultural areas. Each of the apiaries consisted of six colonies, with the sister queens artificially inseminated with semen from the same pool of drones. The bee colony strength and the variability of the vitellogenins in various tissues in foragers from both apiaries were analyzed from May to August. Here, we revealed that colonies from the urban apiary were more abundant than those from the rural apiary. We observed the compensation mechanism during periods of worker deficiency in the bee colony, which was expressed as a change in the Vgs level in the forager tissues. Using the vitellogenin level as a biomarker of the honeybee colony strength can predict the fate of colonies, especially those with low numbers. The high level of Vgs can be a candidate for bee colony depopulation biomarker. [ABSTRACT FROM AUTHOR]

Urbanization significantly impacts river ecosystems, altering fish community structure and dynamics and posing challenges to the sustainable management of these vital resources. In the heavily urbanized Haihe River in China, understanding the spatial and seasonal variations of fish communities and the environmental factors influencing them is crucial for effective conservation and sustainable management. This study investigated fish communities and environmental variables at ten sites along an urbanization gradient in the upstream reach of the Haihe River over four seasons in 2023. A total of 6710 individual fishes representing 30 species were collected. The results showed that the most urbanized section exhibited higher species diversity but was dominated by tolerant, omnivorous species with similar functional traits, indicating functional homogenization. In contrast, less urbanized sections displayed greater seasonal fluctuations and supported species with specialized traits. Key environmental factors influencing fish community dynamics included nitrogen levels, water temperature, dissolved oxygen, and the abundance of the submerged macrophyte Potamogeton crispus. These factors varied spatially and seasonally, mediating the effects of urbanization on fish communities. The findings highlight the importance of environmental factors in shaping fish community dynamics in urban rivers and underscore the need for integrated management strategies that consider both anthropogenic impacts and natural influences to conserve fish diversity, river maintain ecosystem health and ensure long-term sustainability. Sustainable management practices that balance development with environmental protection are vital for preserving ecological integrity and enhancing the resilience of urban river systems to challenges such as urbanization. [ABSTRACT FROM AUTHOR]

To assess the reserve capacity of the body from a physiological point of view, it is important to study the specific “northern” hormone metabolic profile of the body during critical (autumn and winter) periods in apparently healthy individuals born and living in the North.The aim of the work. To study the main parameters of carbohydrate metabolism, as well as possible causes of its disorders in the dynamics of autumn and winter periods in men living in the North.Materials and methods. The autumn (October) and winter (December) stages of the study included 45 men (mean age 40.0 ± 0.8 years) permanently residing in the Magadan Region. We used chemiluminescent immunoassay, enzymatic method and immunochromatographic assay.Results of the study. It was found that the average values of carbohydrate metabolism parameters in the examined male northern residents are comparable with the standard ranges with a shift towards higher values relative to the established limits and do not meet the main criteria of the “polar metabolic type”. “Polar metabolic type” is characterized by hypoglycemia and hypoinsulinemia against the background of elevated serum cortisol values. It is shown that during the critical period of the year from October to December (temperature transition through zero) against the background of relative “hypercortisolism”, activation of the insular apparatus of the pancreas is observed, accompanied by an increase in the insulin level, as well as the development of insulin resistance in the absence of compensatory secretion of β-cells of the pancreas. At the same time, the presence of signs of insulin resistance in northern male residents in the winter period may be determined by an imbalance towards greater dominance of the sympathetic nervous system, formed as a response to the critical period of the year.Conclusion. The obtained results indicate the formation of a transformed “northern” hormone metabolic profile of the body of a modern resident of the North, which should be considered as a certain adaptive response to the modern modification of the socio-economic lifestyle of northern residents (hypodynamia, overeating, etc.).

[Objective] To reveal the vertical distribution characteristics of soil organic carbon, nitrogen, and phosphorus content, soil stoichiometric characteristics (C/N, C/P, 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/P 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/P, and N/P are 17.00~37.33, 62.72~114.50, 3.09~5.18 in the dry season, and 17.72~39.16, 63.21~90.72, 2.39~5.80 in the rainy season. (4) The C/N and C/P 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 P 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 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

Introduction: Scutellaria 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. Methods: The 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. Results: In 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. Discussion: This 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. [ABSTRACT FROM AUTHOR]

We performed monitoring survey of the taxonomic diversity and structure of microbial community of littoral zone in Lake Baikal (Russia) during open-water period from June to October 2020 by DNA-metabarcoding approach. It was shown according to analysis that bacterial community divided into two clusters—Cluster-I (Spring) consisted of bacterial species mostly represented in June and which are living during ice-cover period or got here with surface and ground waters. Cluster-II was formed by so called summer-autumn microbial community. [ABSTRACT FROM AUTHOR]

Simple Summary: Non-biting midges cause a nuisance by swarming near areas where human activities are conducted. Numerous studies have focused on the taxonomic and functional diversity of non-biting midges, while their seasonal population dynamics are less studied. In order to understand the activity patterns of adult non-biting midges, we observed their species diversity continuously over different seasons in an urban wetland park. The species composition of non-biting midges differed significantly in different seasons. Environmental factors such as barometric pressure, temperature, relative humidity, and wind speed were recorded during sampling, and the species variation was significantly correlated with these factors. The results extend our knowledge of the seasonal dynamics of non-biting midge populations and provide a basis for developing strategies to mitigate the hazards of this assemblage. The family Chironomidae is speciose and is present in almost all freshwater habitats. Adult non-biting midges emerge from waterbodies and swarm in high numbers, occasionally disrupting people's outdoor activities. In order to understand the seasonal dynamics of species composition, a continuous observation of non-biting midge diversity was performed. Adult non-biting midges were collected using light traps from the autumn of 2022 to the summer of 2023 in an urban wetland park. Species were identified based on morphological characteristics and DNA barcodes. Alpha diversity was evaluated using Margalef, Pielou, and Shannon–Wiener indexes. Beta diversity was evaluated using unconstrained NMDS analysis and constrained CCA. The impacts of environmental factors, including barometric pressure, temperature, relative humidity, and wind speed, on the variation in species composition were estimated in the constrained analyses. A total of 42 species were identified, with 29 species belonging to Chironominae, 9 species belonging to Orthocladiinae, and 4 species belonging to Tanypodinae. The species composition varied across different seasons. Summer sites and autumn sites shared the highest similarity in diversity, and spring sites presented the lowest diversity. The variation was significantly correlated with environmental conditions. The results showed that seasonality is a factor influencing the diversity of adult non-biting midges. [ABSTRACT FROM AUTHOR]

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]

Respiration of soil heterotrophs—mainly of bacteria and fungi—is a substantial part of carbon balance in terrestrial ecosystems, which tie up organic matter decomposition with the rise of atmospheric CO2 concentration. Deep understanding and prediction of seasonal and interannual variation of heterotrophic and autotrophic components of CO2 efflux from soil is limited by the lack of long-term, full-year measurements. To better understand the impact of current climate changes on CO2 emissions from soils in the mixed forest and mowed grassland, we measured CO2 efflux every week for 2 years. Heterotrophic (SOM-derived + leaf litter) and root-associated (root with rhizosphere microorganisms) components were partitioned by the root exclusion method. The total CO2 efflux from soil was averaged 500 g C m−2 yr−1 in the forest and 650 g C m−2 yr−1 in the grassland, with shares of the no-growing cold season (Nov–Mar) of 22% and 14%, respectively. The heterotrophic component of CO2 efflux from the soil averaged 62% in the forest and 28% in the grassland, and it was generally stable across seasons. The redistribution of the annual precipitation amounts as well as their deficit (droughts) reduced soil respiration by 33–81% and heterotrophic respiration by 24–57% during dry periods. This effect was more pronounced in the grassland (with an average decline of 56% compared to 39% in the forest), which is related to lower soil moisture content in the grassland topsoil during dry periods. [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 species composition and fatty acid composition, seasonal dynamics of biomass, and production and productivity of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) of the zoobenthos of the Ob River and its tributaries, the Inya River and the Tula River, have been studied. The total contents of EPA and DHA in all taxa of zoobenthos are relatively high, except for Trichoptera, Bivalvia, and Gastropoda. Values of the EPA and DHA contents fall in the ranges reported in literature for the relevant taxa from various habitats, which confirms the hypothesis about the principal contribution of the phylogenetic factor to the contents of EPA and DHA of zoobenthos. The similarity of the species composition between the Inya River and the Tula River is lower than that between the Ob River and each tributary, which may be due to different hydrological features and types of bottom sediments, as well as a drift of benthic invertebrates from the tributaries into the main channel. The Ob River, the Inya River, and the Tula River have nearly similar values of zoobenthos production and EPA and DHA of productivity, while they differ from these parameters of the Yenisei River and its tributaries reported in literature, which have another species composition of benthic invertebrates. The EPA and DHA productivity, i.e., the biochemical quality of the fish food under similar values of the production of zoobenthos, is determined by the species composition of zoobenthos, which depends on the complex of environmental factors. [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]

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]

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]

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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]

Mangrove forests, found primarily in tropical and subtropical coastal regions, support diverse microbial communities that are crucial for nutrient cycling and energy flow and then sustain mangrove ecosystem integrity. This study investigated the seasonal dynamics of bacterial communities in mangrove sediments of Shupaisha island (Zhejiang Province, China) through amplifying and high-throughput sequencing bacterial 16S rRNA gene fragments. Proteobacteria (23.59–44.40%), Actinobacteria (4.92–19.01%), and Bacteroidetes (4.31–22.79%) dominated the bacterial phyla in Shupaisha mangrove sediments with the highest diversity indices in winter. Actinobacteria were more abundant during winter (13.27%) and spring (14.36%), while Bacteroidetes abundance was highest in summer, significantly correlating with temperature. Significant differences in bacterial community composition were observed between winter and summer, while spring and autumn exhibited similar distribution, indicating a transitional pattern in bacterial community dynamics, with temperature and sand content being the most influential factors. This study enhances our understanding of the seasonal characteristics of bacterial communities in the mangrove ecosystems, potentially providing valuable insights into monitoring and assessing the health and stability of mangrove ecosystems in Zhejiang Province.

Monitoring zooplankton diversity and community dynamics is essential for understanding ecological processes within freshwater ecosystems. Environmental DNA (eDNA) has been increasingly employed in this field due to its efficiency and accuracy. However, its potential applications in freshwater ecosystems require further validation. In this study, we evaluated the performance of 18S rRNA and COI primers for freshwater zooplankton diversity monitoring and systematically compared the selected primers with the microscopy method in Qiandao Lake, China. Our results indicated that the COI primer marker (mlCOIintF/jgHCO2198) was more suitable for freshwater zooplankton diversity monitoring than 18S rRNA. The eDNA method identified a total of 102 species, whereas the microscopy method detected 111 species. Non-metric multidimensional scaling (NMDS) analysis and nonparametric multivariate statistical tests revealed that both abundance and biomass species compositions determined by microscopy differed significantly from those based on eDNA reads. Both methods detected significant seasonal changes in zooplankton community species composition, while eDNA provided a comprehensive view of the complex interactions within the community. Both methods indicate that rotifers are the primary group driving seasonal changes in the zooplankton community. The eDNA identified more environmental factors associated with seasonal changes in zooplankton communities than microscopy, including dissolved oxygen (DO), nephelometric turbidity unit (NTU), ammonia nitrogen (NH3-N), and total phosphorus (TP). The eDNA reads of rotifer and crustacean plankton increased linearly with their morphological abundance but not with biomass. Furthermore, combining morphological abundance and biomass as predictor variables for eDNA reads moderately enhanced the explanatory power compared to using them individually. Although eDNA cannot yet replace morphological methods, its efficiency and sensitivity make it a valuable complementary tool for zooplankton monitoring, with considerable potential for future applications.

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.

Artemia is widely used in aquaculture as a live feed. The presence of highly unsaturated fatty acids is a key determinant of nutritional value. The purpose of this study was to study the fatty acid composition of total lipids of Artemia cysts (Artemia sp.), taken from two lakes in the North Kazakhstan region in different seasons of the year, and the influence of phytoplankton composition on the fatty acid profile. Phytoplankton sampling was carried out by the sedimentation method, and a camera analysis of the sample was carried out using a microscope. Extraction of total lipids was carried out by a binary mixture of organic solvents chloroform-ethanol (2:1). Gas chromatographic separation of fatty acids was carried out after methanolysis of lipids to obtain methyl esters of fatty acids. The seasonal dynamics in the content of both the main groups of fatty acids and individual fractions are shown, which is associated with abiotic and biotic conditions for the growth of natural populations. The values of the unsaturation coefficient were twice as high in the spring samples of Artemia cysts as compared to the autumn samples for the populations of Lake Stanovoye. In the composition of polyunsaturated acids, such acids as 18:3n3 linolenic acid were found (from 4.13% to 23.37%); 20:5n3 eicosapentaenoic acid (from 8.24% to 16.27%); and 18:2n6t linoleidic acid (from 3.84% to 13.53%).

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]

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]

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]

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]