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The adaptive physiological functions of black Bengal goats (Capra hircus) of coastal regions were compared with goats from the plains during winter, spring, and summer seasons. Goats in the coastal zone had significantly (P < 0.01) higher plasma electrolytes levels. Goats in the plains zone had significantly (P < 0.01) higher haemoglobin, PCV, TEC, and erythrocyte indices and lower TLC values. Glucose, total protein, and creatinine were significantly (P < 0.01) lower, whereas cholesterol, BUN, and SGPT were significantly (P < 0.01) higher in goats of coastal zone. Regardless of zones, glucose, total protein, and creatinine levels were higher in winter, cholesterol and SGOT levels were higher in spring, and BUN was higher in summer. Goats from coastal areas had significantly (P < 0.05) higher urinary pH and urea levels. Goats in the coastal zone had significantly (P < 0.05) higher cortisol concentrations. From the above study, we can conclude that salinity of feed, soil and water does not significantly affect the homeostasis of black Bengal goats reared in coastal areas, indicating their adaptability to saline coastal environments and their potential for reproduction in a climate-resilient livestock system. The fodder, water and soil of coastal areas contain higher amounts of sodium, zinc, and iron in the compared to plain areas. Black Bengal goats raised in coastal regions are able to maintain their homeostasis without much altering hemato-biochemical and endocrine profiles. Black Bengal goats can be a good option for climate resilient animal husbandry system. [ABSTRACT FROM AUTHOR]

Sleep-wake rhythm regularity was evaluated with the interquartile range (IQR) of sleep duration, sleep onset, sleep offset, and mid-sleep time. Purpose: Determine the relationship between types of dietary patterns and risk of sleep apneaMethod: In this descriptive-analytical-cross-sectional study, during one year, the sleep status of all patients at Qods Hospital Qazvin sleep clinic was investigated with polysomnography. Sleep disturbances in depressed patients are accompanied by various changes in sleep architecture, including decreased total sleep time, decreased sleep efficiency, prolonged sleep latency, decreased slow wave sleep, shortened REM (rapid eye movement) sleep latency, and increased REM density. Results showed that melatonin with no serious side effects is effective in improving: 1-The initiation and maintenance of sleep, 2-Sleep duration, 3-Night awakenings 4-Parasomnias and 5-Daily performance; but is ineffective in bedtime resistance, sleep anxiety and sleep-disordered breathing. Furthermore, decreased sleep efficiency, changes in the macro and microarchitecture of sleep, and increased respiratory events during rapid eye movement (REM) sleep are common findings in these patients. [Extracted from the article]

The goal of the current study is to evaluate the Seasonal variation in physio-chemical properties Khudia Dam in Bilaspur, Chhattisgarh. Analysis of the water was done from the perspective of monitoring water quality and to get up-to-date information on connected changes in the physico-chemical parameters in the habitat. The investigation was conducted over the course of a year (2019 to 2021). The following physico-chemical parameters were measured in three different seasons (monsoon, winter, and summer) in order to determine the water chemistry of Khudia dam: water temperature, pH, total dissolved solids, electrical conductivity, dissolved oxygen, BOD, COD, chloride, salinity, alkalinity, and hardness. Pre-monsoon water quality was found to be rather acceptable according to the data, while monsoon, post-monsoon, and pre-monsoon are the seasons with the highest pollution levels. Due mostly to the effects of the terrestrial runoff, the monsoon's water quality conditions were problematic. The water quality of this water body would be adversely impacted if the load of pollution and anthropogenic activity grows in the dams in the future, hence appropriate measures must be made to sustain and manage this ecosystem. [ABSTRACT FROM AUTHOR]

Climate variation throughout the year affects photosynthesis and other physiological processes correlated with plant development and yield. This study aimed to evaluate the changes in the physiological attributes of Coffea canephora genotypes over the year in the Brazilian Amazon and assess their relationship with crop yield. The experiment was carried out in three cultivation systems with three genotypes. The evaluations were carried out in four periods: the peak of the dry season (S1); the beginning of the rainy season (S2); the peak of the rainy season (S3); and the beginning of the dry season (S4). A dataset of gas exchange, pigment indices, chlorophyll fluorescence, branch growth, and coffee yield was obtained. The group of gas exchange variables was the main contributor to treatment discrimination and was most affected by seasons. As expected, the values of gs, E, and A were significantly lower in S1, while the values of VPDLeaf-ar, TLeaf, and IWUE were significantly higher. Our results demonstrate that climatic seasonality affects the photosynthesis of Amazonian Robustas coffee, even under irrigated conditions, particularly in response to increased VPD. The physiological variables analyzed at the leaf level, even in different periods, did not explain the differences in the yield of C. canephora. [ABSTRACT FROM AUTHOR]

The influence of seasonal variation on animal behavior is a critical component of habitat selection analyses. To examine this relationship, we conducted multi-scale analyses of Lesser Prairie-Chicken (Tympanuchus pallidicinctus) habitat selection in relation to anthropogenic infrastructure associated with oil and gas development, mesquite, and trees during the spring and summer at home range and lek area scales. We tracked 159 Lesser Prairie-Chickens using VHF radiotelemetry or PTT-GPS transmitters in the sand shinnery oak prairie region of eastern New Mexico, USA. We used discrete choice models and logistic regression to assess seasonal patterns of habitat selection at home range and lek area scales, respectively. The static habitat features we examined allowed us to observe differential patterns of habitat selection between the two seasons, revealing an overall increase in the degree of avoidance following the spring season. Results of our home range scale analysis indicate that utility pole density, mesquite cover, and proximity to active well pads, private roads, and mesquite have significant negative effects on habitat selection during both seasons. Avoidance of high utility pole densities was significantly greater during the summer compared to spring. Lek area habitat selection results were similar, but differences in sensitivity to features between seasons were stronger. Avoidance of high mesquite cover and utility pole and tree densities, in particular, was significantly greater in the summer. The effects of density and cover of these features, which have previously been understudied in Lesser Prairie-Chicken research, provide critical information for future conservation practices. Furthermore, our study highlights the importance of accounting for potential seasonal patterns of study species to best examine habitat selection. [ABSTRACT FROM AUTHOR]

Phytoplankton phenology, connected to the seasonal variation in physiology, populations, community composition or whole community aggregated and biological interactions, responds to downwelling irradiance, temperature and nutrient supply. Quantitative niche models estimate picophytoplankton cell abundance based on photosynthetic active radiation (PAR), temperature and nitrate and thus can be used to study picophytoplankton phenology. We used quantitative niche models to estimate the abundance of picophytoplankton groups for the global ocean in 1-degree grids and the upper 200 m of the water column. The inputs of the models were the monthly climatology of temperature and nitrate from the World Ocean Atlas (WOA) and PAR from the Moderate Resolution Imaging Spectroradiometer (MODIS-Aqua). We aimed to study phenological cycles of picophytoplankton and establish a mean baseline to contrast changes in the distribution of Prochlorococcus, Synechococcus and picoeukaryotic phytoplankton. Prochlorococcus presented high abundances in ≥ 9 months in an uninterrupted area between 20ºN-S, whereas Synechococcus and picoeukaryotic phytoplankton showed high abundances in three areas: between 20ºN-S, and around 45ºN and 45ºS. Abundance seasonal change was 7, 15 and 28% around the annual mean, respectively, and the three groups presented two peaks. The seasonality of picophytoplankton was among the lowest compared to other phytoplankton groups and processes in the global ocean. The combined effects of groups' ecological sensitivity captured by the niche models and basins environmental variability provided by the WOA shaped the uneven phenological cycle of picophytoplankton groups. [ABSTRACT FROM AUTHOR]

Rain-fed fig culture is known to provide a good quality of dried figs, while almost no research has been reported so far on the enzyme activity comparisons of seasonal variations among terminal buds in this plant. Toward this goal, we evaluated the physiochemical changes of terminal buds of fig 'Sabz' and their micromorphology during the dormant season (November to April) using Scanning Electron Microscope (SEM) analysis during two consecutive years (2016 and 2017). Results indicated that the highest contents of total sugars in terminal fig buds were registered in January and the lowest values were noticed in April. SEM analysis showed the presence of vegetative terminal fig buds during the dormant season and after bud-break in April. An increasing trend was observed for the protein content, length and diameter of terminal buds at the beginning of bud-break. In dormant buds, ascorbate peroxidase, peroxidase and catalase enzymes exhibited initially an ascending pattern, while it decreased from December. A second increase for these enzymes occurred during the dormant season until bud-break. Superoxide dismutase activity increased in buds during the dormancy season until bud-break. Proline content remained stable in buds from November to February, while it decreased rapidly until bud-break. Furthermore, a downward trend of the total phenol content in buds was observed between the onset and end of dormant period. In general, the dormant buds in 'Sabz' fig cultivar were metabolically active with a short dormant period under the rain-fed conditions. [ABSTRACT FROM AUTHOR]

We describe seasonal changes in the physiology of reproductive organs of Saker Falcons electrocuted on an electricity power line in Mongolia. Macroscopic examination of the gonads revealed asymmetry in testes size, with bias to the left body side. This asymmetry declined with seasonal increase in testes size during the main egg-laying period of the breeding season. In females, 91% possessed both left and right ovaries (N = 161); there was no visible oviduct associated with the right ovary and it was smaller than the functional left ovary. Both ovaries showed seasonal development in size, becoming larger during the peak egg-laying period. Hierarchical preovulatory follicular development was recorded in two females, with ca. 5 mm difference in the diameter of sequential follicles. Both sexes developed brood patches during the main incubation period, with adults more likely to exhibit brood patches than juveniles. Among juveniles, at least 82% of females and 91% of males were non-breeders without brood patches. The high electrocution rate at our studied power line provided a rare opportunity to examine the non-breeding component of the Saker population. Juveniles predominated in the non-breeding population during the main egg-laying period (89%, N = 65), with the proportion of adults electrocuted being significantly lower among females. Only a small proportion of juvenile females exhibited gonadal evidence of breeding, consistent with the low observed frequency of juvenile breeders at nests. The demographic composition of the non-breeding population is consistent with female mortality rates exceeding that of males, and potentially indicates incipient population decline. [ABSTRACT FROM AUTHOR]

The changes in plasma cortisol, oxidative status, skin temperature and physiological responses of Karan Fries heifers were monitored during thermoneutral (TN; THI = 73), hot-dry (HD; THI = 83) and hot-humid (HH; THI = 85) seasons. Six heifers (age = 14-I8 months) were followed during each season. All the physiological measures viz. rectal temperature (RT), respiration rate (RR) and pulse rate (PR) displayed a diurnal rhythm and were higher (p < 0.05) in the evening as compared to the morning with maximum variations seen in HH season. The skin temperature (dorsal, abdomen and ear) increased (p ˂ 0.05) in hot seasons mainly in HD as compared to TN season. A significant (p < 0.05) increase was observed in the concentration of plasma cortisol, superoxide dismutase (SOD) and malondialdehyde (MDA) during hot seasons compared to TN season. All the recorded physiological and oxidative parameters were positively correlated with the temperature-humidity index (THI). However, the dry matter intake was negatively correlated with THI during all seasons. The results reveal that the heifers exhibited more signs of heat stress during HD and HH seasons which were reflected by higher concentrations of cortisol, SOD, MDA and more deviation in the normal daily rhythm of various physiological functions. [ABSTRACT FROM AUTHOR]

Clematis fruticosa Turcz. is a dominant native shrub with the potential for spontaneous vegetation succession for restoration of the ecologically fragile and arid Daqing Mountains of Inner Mongolia, which represent an important ecological transition zone in northern China. However, knowledge regarding the interactions between native species and their root‐associated arbuscular mycorrhizal (AM) fungi across different seasons and elevation gradients remains obscure. High AM fungal spore density, root colonization and arbuscular richness suggested that C. fruticosa could establish intimate symbiotic associations with AM fungi. A total of 174 AM fungal virtual taxa were identified from rhizosphere soil samples, and Glomus was dominant. The most distinct AM fungal community composition and the greatest richness and diversity were observed in the spring and at the highest elevation. Seasons • elevation interactions significantly affected Simpson diversity but not AM fungal community composition, observed richness and Shannon index. Seasons had a significant direct on AM fungal observed richness and Shannon index, and elevation had a significant direct on AM fungal observed richness. Soil available phosphorus was the most important driving factor in AM fungal richness and diversity, followed by seasons and soil moisture content. These results provied new insights suggesting that there are active and diverse "functional ingredients", for example root‐associated AM fungi during the growing season, particularly with an earlier onset in the spring. They are potentially major contributors to the re‐vegetation of degraded lands and the maintenance of soil structure in arid and semiarid ecosystems, which is attributable to seasonal variation in host physiology in stressful environments. Highlights: We studied the effects of seasons and elevation on AM fungal richness, diversity and community in ecologically fragile mountain areas.Distinct community composition and greater richness and diversity of AM fungi were detected in the spring and at the highest elevation.AM fungal richness and diversity depended on certain soil variation related to seasons and elevation. [ABSTRACT FROM AUTHOR]

Mineral deficiency of roughages has been widely proven in research to affect productivity in ruminants. Accurate determination of grass minerals and biochemical profile of blood will provide valuable information to assist in diagnosis, prognosis and treatment of nutritional diseases of veterinary importance. This study, therefore, aimed to document the variations in levels of some selected micro and macro mineral concentrations of both grass and blood and blood chemistry as influenced by season of the year (winter, spring, summer and autumn) in selected communal farming locations of the North West Province of South Africa. Blood and Grass samples were collected from herds and areas distributed throughout the North West Province. Areas selected were the Southern region (5 herds, n=48), Bophirima region (8 herds, n=62), Central region (9 herds, n=70) and Bojanala region (6 herds, n=45). The phosphorus (P) and calcium (Ca) concentrations of grass (3.65 and 15.22 mg/g) were increased (P<0.05) during the spring and summer, respectively, compared to other seasons while lower P, Ca and magnesium (Mg) concentrations (0.89, 6.45 and 0.97 mg/g) were obtained during the winter. Serum P, Ca, Mg, Iron (Fe), potassium (K) and copper (Cu) concentration were significantly (P <0.05) influenced by change in season. Higher (P <0.05) serum P, Mg, potassium (K) and copper (Cu) concentration were obtained during the summer compared to other seasons. However, Ca and Iron (Fe) were significantly (P <0.05) increased during the summer, autumn and spring than winter period. Albumin, alanine transaminase (ALT), total bilirubin (TBIL), cholesterol (CHOL), creatinine kinase (CK), glucose (GLU) and lactate dehydrogenase (LDH) concentrations were significantly (P<0.05) reduced in summer compared to other season. Seasonal variations across the year have a great influence on mineral concentration of the grass and subsequently on blood serum concentrations. Therefore, proper documentation and timely evaluation of nutritional quality of available forages is required. [ABSTRACT FROM AUTHOR]

Two experiments were conducted to evaluate the effects of body size and seasonal variation on organ indexes, digestive enzymes and plasma biochemistry parameters of triploid rainbow trout. Results in experiment 1 showed that compared with small fish, large fish had significantly (P < 0.05) higher values of organ indexes, higher plasma nutrient contents as well as higher specific activities of lipase in pyloric caeca and amylase in the intestine. Results in experiment 2 showed that fish in spring or winter had greater intestine length as well as lower specific activities of protease and lipase in pyloric caeca (P < 0.05). Fish in autumn had the highest specific activities of acid protease in the stomach and alkaline protease in pyloric caeca, lipase in pyloric caeca as well as nutrient contents in plasma, while fish in summer had the lowest liver and viscera weight as well as plasma nutrient contents. Based on data of organ indexes, digestive enzymes and plasma biochemistry parameters, the physiological status of triploid rainbow trout were affected by fish size and seasonal variation. Normal reference ranges of organ indexes and plasma biochemical parameters of triploid rainbow trout were preliminarily established, which are partly different from diploid trout. [ABSTRACT FROM AUTHOR]

While the effect of weather and seasons on physical activity (PA) is well documented for leisure-time physical activities in western countries, scant information is available for developing countries where lifestyle PA is the major source of energy expenditure (EE). In Bangladesh, the traditional calendar divides the year to six seasons that last two months each: summer, rainy, autumn, late autumn, winter, and spring. We developed the Past Year Physical Activity Questionnaire to record culturally relevant physical activities and to help assess the seasonal variation in total and domain-specific PA in Bangladesh. We have applied this tool to 162 men and women aged 18-60 years residing in Dhaka city and in the northern rural district of Thakurgaon. Repeated measures analysis of variance (RMANOVA) was used to test for evidence of variation in PA between place and seasons. The age- and gender-adjusted model revealed significantly lower levels of EE in urban residents compared to rural residents across all seasons and domains. We also found evidence of seasonal variations in moderate-to-vigorous physical activity (MVPA) MET-min/weekamong rural participants only; for total PA (ranging from 3192 in autumn to 4124 in winter; p = 0.0001) and for two domains: the occupation domain (ranging from 935 in autumn to 1645 in winter; p = 0.0001) and the leisure time domain(ranging from 229 in late autumn to 272 in rainy season; p = 0.005). Seasonality in gardening was also noted (ranging from 2.46 in late autumn to 29.28 in rainy season; p = 0.0001). There were no seasonal differences of total and domain-specific MVPA in urban except household-related PA. Among rural participants, PA was higher in the summer, rainy, and winter seasons and lower in autumn and late autumn. The most common leisure-time physical activities were walking, bicycling, and swimming with higher participation in the rural area. Leisure-time physical activity needs to be promoted to urban residents all year long but more focused on autumn, late autumn, and spring in rural areas. [ABSTRACT FROM AUTHOR]

In this study, zooplankton community of Nazik Lake studied seasonally. Zooplankton samples were collected from three different stations with standart hydro-bios plankton net, both horizontally and vertically. In the lake 25 zooplankton species were identified. Zooplankton samples were consisted of 14 Rotifera, 8 Cladocera, and 3 Copepoda, respectively. Rotifera was the dominant group of zooplankton with regard to species numbers and densities. [ABSTRACT FROM AUTHOR]

While seafood is consumed worldwide, eating raw seafood is more popular in Asian countries. Consuming seafood promotes many health benefits, but is not risk free because it can be contaminated with foodborne pathogens, which can result in disease outbreaks. In this study, we performed the risk assessment of Vibrio parahaemolyticus in raw oysters in Taiwan under the seasonal variations, time horizons, and climate scenarios. Sixty-four scenarios with 100,000 iterations were performed with Monte Carlo simulation. The results showed the estimated risk of eating oysters under the baseline to be 2.2 × 10−5, 4.5 × 10−5, 9.4 × 10−5, and 6.2 × 10−5 per serving in winter, spring, summer, and fall, respectively. The risk in that baseline in this study was found to be intensified by 23%, 35%, 37%, and 65% by RCP2.6, RCP4.5, RCP6.0, and RCP8.5, respectively, and it was intensified to 0.18, 0.38, and 0.64 times in 2016–2035, 2046–2065, and 2081–2100, respectively. Mitigation strategies simulated in this study show that the risk in that baseline could be reduced by 64–87%, 52–67%, and 47–63% with immediate refrigeration, depuration, and freezing treatment, respectively, and could be reduced by up to 100% by mild thermal treatment, thermal shock and irradiation. Reducing and or controlling the risk of raw oysters will prevent foodborne outbreaks from occurring. Therefore, the findings obtained from this study may help the food safety authority and food managers in food industry in their decision-making process. • A risk assessment framework for raw oysters in Taiwan was developed. • Post-harvest intervention measures were evaluated to reduce/control the risk. • The risk of eating raw oysters in summer is greater than other seasons. [ABSTRACT FROM AUTHOR]

1. Variation in spring phenology – like tree budburst – affects the structure of insect communities, but impacts of autumn phenology have been neglected. Many plant species have recently delayed their autumn phenology, and the timing of leaf senescence may be important for herbivorous insects. 2. This study explored how an insect herbivore community associated with Quercus robur is influenced by variation in autumn phenology. For this, schools were asked to record, across the range of oak in Sweden, the autumn phenology of oaks and to conduct a survey of the insect community. 3. To tease apart the relative impacts of climate from that of tree phenology, regional tree phenology was first modelled as a function of regional climate, and the tree‐specific deviation from this relationship was then used as the metric of relative tree‐specific phenology. 4. At the regional scale, a warmer climate postponed oak leaf senescence. This was also reflected in the insect herbivore community: six out of 15 taxa occurred at a higher incidence and five out of 18 taxa were more abundant, in locations with a warmer climate. Similarly, taxonomic richness and herbivory were higher in warmer locations. 5. Trees with a relatively late autumn phenology had higher abundances of leaf miners (Phyllonorycter spp.). This caused lower community diversity and evenness on trees with later autumn phenology. 6. The findings of the present study illustrate that both regional climate‐driven patterns and local variation in oak autumn phenology contribute to shaping the insect herbivore community. Community patterns may thus shift with a changing climate. [ABSTRACT FROM AUTHOR]

ContentsSummaryI.IntroductionII.Evolving modes of phenological studyIII.The phenocam approachIV.Applications of the phenocam methodV.Looking forwardAcknowledgementsReferences Summary: Global change is shifting the seasonality of vegetation in ecosystems around the globe. High‐frequency digital camera imagery, and vegetation indices derived from that imagery, is facilitating better tracking of phenological responses to environmental variation. This method, commonly referred to as the 'phenocam' approach, is well suited to several specific applications, including: close‐up observation of individual organisms; long‐term canopy‐level monitoring at individual sites; automated phenological monitoring in regional‐to‐continental scale observatory networks; and tracking responses to experimental treatments. Several camera networks are already well established, and some camera records are a more than a decade long. These data can be used to identify the environmental controls on phenology in different ecosystems, which will contribute to the development of improved prognostic phenology models. [ABSTRACT FROM AUTHOR]

BACKGROUND: Breastfeeding (BF) neonates generally lose weight after birth. Neonatal factors like gestational age, birth weight and mode of delivery can affect the neonatal weight loss after birth. Similarly, maternal age, parity and illness may contribute to newborn weight loss. However, influence of the time of birth and season on changes in weight is not well elucidated. OBJECTIVE: The aim of this study is to determine the effect of birth time and the seasonal variations on weight loss in BF newborns. METHODS: In this retrospective study of a prospectively maintained database of two sets of groups, from January 2013 to October 2016, were evaluated- Birth time group and Seasonal group; Birth time of the groups was: night time 7pm to 7am and day time 7am to 7pm; and the seasonal variations groups studies were summer, fall, winter and spring. Weight loss of >5%, 7%, and 10% at <24 hours (h), 48 h and 72 h of birth, respectively, were considered as a significant weight loss. Preterm, exclusively formula fed and neonates admitted to NICU were excluded. RESULTS: A total of 2044 newborns were analyzed. In the birth time group, babies born during the night time had significantly lost >5% of birth weight at <24 h (p < 0.01) and >7% birth weight at <48 h of life (p < 0.02). Weight loss >10% at <72 h was similar in both birth time cohorts. C-section, prolonged rupture of membrane, and maternal pre-delivery hospital stay for >12 h were significant contributing factors. Whereas, seasonal variations were not associated with weight loss in neonates. CONCLUSION: BF babies born at night time lose significantly more weight during the first two days of life and seasonal association was not found to affect weight loss in the neonates. [ABSTRACT FROM AUTHOR]

Many marine organisms spend the early life history stages in neuston domain. Although the importance of ichthyoneuston, few studies were developed in the Southwest Atlantic Ocean. Therefore, this study aimed to improve the knowledge on ichthyoneuston of the Brazilian coast analyzing the vertical stratification and horizontal distribution of these organisms. Neuston samples were collected in daylight between 20°S and 23°S from February to April 2009 (late summer/early autumn; rainy season) and from August to September 2009 (late winter/early spring; dry season). Eggs of six taxa were identified: Anguilliformes, Engraulidae, Clupeidae, Synodontidae, Trichiuridae, and Maurolicus stehmanni (Sternoptychidae). The neustonic larval fish assemblage was composed by 40 families and 63 species. Mullidae and Myctophidae larvae were the most abundant in the rainy period while Mullidae and Mugilidae dominated in the dry season. Seasonal and spatial variation of larval fish assemblages in the neuston were structured by oceanographic features. The larval fish abundance on the outer slope stations may have been favored by the advection of an anticyclone that encompassed most of the study region during the cruise periods. In the rainy season, salinity and local depth structured the larval fish assemblage in a cross‐shelf gradient, while in the dry season the larval assemblage was structured around temperature and north‐south gradient. In the dry season, the cross‐shelf gradient was less pronounced mainly because of the low abundance and frequency of mesopelagic larvae. The low frequency and abundance of some species are probably related to the net avoidance of fish larvae during the day or dial vertical migration, as many species migrate to deeper layers during the day and ascend to neuston only at night. Nevertheless, the present study presented baseline information about the seasonal and spatial variation of the neustonic larval fish assemblage influenced by the oceanographic conditions in the Campos Basin. We recommend to additionally collect night samples to decrease larval escapement rates and to compare night versus day catches to further investigate the influence of daily migration in the neustonic larval fish in the area. [ABSTRACT FROM AUTHOR]

Lantana camara species is generally seen only as a detriment to plantations but it also possess medicinal potential. This work aimed to analyse the essential oil (EO) yield and chemical composition of fresh and dry leaves versus seasonal variation of L. camara, as well as its inhibition of fungi, bacteria and towards the enzyme acetylcholinesterase. Variations in EO yield and its chemical composition in front of the aforementioned variations were found to be notorious. EO obtained from fresh and dry leaves throughout the day (6am, 12pm and 6pm) presented inhibition of Candida albicans higher than the standards. However, what is clear is that the EO from dry leaves of L. camara were the best inhibitors of fungi, bacteria and also of AChE, this latter standing out by a potent inhibition reaching 96.10%, superior to the standard used (90.31%). [ABSTRACT FROM AUTHOR]

Sand flies were collected in a location from Romania in order to estimate their abundance and seasonal variation in correlation with environmental and anthropic factors. From May to October 2017, eight premises with different animal species were sampled for sand flies in a household from Fundătura village, Vaslui County, in North-Eastern Romania. Animal-related data, shelter-related data, and climatic parameters were recorded. All (n = 150) collected sand flies were Phlebotomus perfiliewi. A mono-modal type of abundance trend has been recorded (a single peak at the beginning of August). The first day of capture was in mid-July. The total number of females during the peak season was significantly higher than the total number of males. The highest percentage of males was recorded at the beginning and at the end of the sand fly activity. Only the traps placed in the poultry enclosure built from clay and wood were positive. A strong positive correlation was recorded between the total number of collected sand flies and the minimum and the maximum temperature. The analysis of the climatic data shows that the first presence of sand flies was registered only after the average minimum temperature for the previous 7 days was above 15 °C. [ABSTRACT FROM AUTHOR]

Seasonal variations have been described in humans in several variables such as sleep, mood, appetite, food preferences, or body weight. We hypothesized that these variations could also influence the decrease in body weight rate in patients submitted to body weight loss interventions. Thus, here we tested the variations of weight loss according to the time of the year the surgery took place in a group patients (n = 1322) submitted to bariatric surgery in the Hospital Universitari de la Vall d'Hebron in Barcelona (geographical coordinates: 41°25ʹ41″N 2°8ʹ32″E). For the analysis, the percentage of total body weight loss (%TWL), excess body weight loss (%EWL) and percentage of body mass index loss (%BMIL) were calculated at 3 (n = 1255), 6 (n = 1172), 9 (n = 1002), and 12 months (n = 1076) after surgery. For %EWL and %BMIL a statistically significant seasonal variation was detected when the variables were calculated at 3 months, but not at the other times, with more weight loss in summer-fall. However, seasonal variations were not detected for %TWL (p = 0.09). The mean amplitude of the seasonal rhythm for %EWL was of 1.8%, while for the rhythm of %BMIL was 0.7%. Moreover, a second peak was detected in January-February modulating the seasonal rhythm of the two variables. Results confirm seasonal variations in humans and indicate that short term responses to weight loss can be modulated by the time of year. [ABSTRACT FROM AUTHOR]

Plant growth and nitrogen (N) uptake of Encore® azalea 'Chiffon' (Rhododendron sp.) grown in a traditional plastic container or a biodegradable container made from recycled paper were investigated over the 2013 growing season. Three hundred twenty 1-year-old azalea liners, grown in two types of containers, were fertilized twice weekly with 250 mL N-free liquid fertilizer with no N or 15 mm N from ammonium nitrate (NH4NO3). Biweekly from 10 May to 3 Dec., five plants from each N rate and container type were selected randomly to measure plant height, widths, and leaf chlorophyll content in terms of soil-plant analysis development (SPAD) readings, and were then harvested destructively for nutrient analyses. Leaf SPAD readings and tissue N concentration were influenced mostly by N rate rather than container type, with 15 mm N producing greater values than the no-N treatment. Leaf SPAD readings increased from May to August and decreased from September to December. Using 15 mm N, plastic containers generally resulted in similar or increased plant growth [plant growth index (PGI) and dry weight] and N uptake from May to August as in biocontainers, with greater SPAD readings, leaf and root dry weights, stem and root N concentrations, and leaf and root N content than biocontainers at some harvests. However, biocontainers resulted in greater PGI, dry weights, and N content (in leaves, stems, roots, and total plant) than plastic containers later in the season, from September to December. These differences appeared in September after plants grown in plastic containers ceased active growth in dry weight and N uptake by the end of August. Plants grown in biocontainers had extended active growth from 13 Sept. to 9 Nov., resulting in greater tissue N content and greater N uptake efficiency. The biocontainers used in this study produced azalea plants of greater size, dry weight, and improved N uptake by increasing growth rate and extending the plants' active growth period into late fall. The beneficial effects likely resulted from greater evaporative cooling through container sidewalls and the lighter color of the biocontainers, and therefore led to lower substrate temperatures and improved drainage. [ABSTRACT FROM AUTHOR]

Spinach is an annual, cool-season, green leafy vegetable that in temperate areas can be grown year-round. However, different seasons can influence the quality and shelf life of the produce. The objective of this study was to investigate the influence of different seasons on the quality of baby spinach leaves during growing and postharvest storage. The study was initiated in early Nov. 2013 and culminated toward the end of Oct. 2014, then was repeated from Nov. 2014 until Oct. 2015. A 4 3 5 3 3 factorial experiment was laid out in a randomized complete block design with four replicates per treatment. The treatments were arranged as follows. In autumn, winter, spring, and summer, leaves were kept up to 12 d at three different temperatures: 4, 10, and 20 °C. Parameters recorded are weight loss, leaf length, total flavonoids, and antioxidant activity. Results of the study demonstrate that the level of antioxidants in winter remained stable during storage, specifically at 4 °C, followed by autumn and spring. In contrast, the summer season reflected the worse potential of retaining a level of antioxidants compared with the other seasons. On day 12, at a storage temperature of 4 °C, winter maintained 0.55 mg·g-1 dry weight (DW), whereas autumn, spring, and summer had 0.41, 0.40, and 0.11 mg·g-1 DW, respectively. In conclusion, it is recommended that baby spinach growers consider winter, autumn, and spring for growing baby spinach to manage the quality favorably during the postharvest storage period in South Africa. [ABSTRACT FROM AUTHOR]

To elucidate spatial and seasonal variations of radiocesium (134Cs and 137Cs) concentrations in ayu Plecoglossus altivelis, amphidromous fish samples were collected both from shallow coastal waters in March 2014 and from seven rivers in Fukushima Prefecture during May–October 2014. Of the rivers, two were located within the designated evacuation zone. After standard length (SL) and body weight measurements, fish were dissected to two parts: body without head and internal organs, BD; head and internal organs, HI. Radiocesium concentrations in these parts were measured using germanium semiconductor detectors. Those in the whole body (WB) were reconstructed using their concentrations and weights. The 137Cs concentrations in BD in oceanic samples (4.3–6.7 cm SL) were below the detection limit, whereas those in riverine samples (6.4–18.8 cm SL) were 0.719–902 Bq kg−1-wet. Statistical analyses indicated a best-fit linear mixed-effects model including "SL" and "sampling site" as explanatory variables. Significant differences in 137Cs concentrations in BD among rivers were detected. Our results indicate that 137Cs concentrations in BD of riverine ayu, which showed lower but site-specifically constant values compared with those in HI or WB, are useful as a good indicator of radiocesium contamination of the respective rivers. [ABSTRACT FROM AUTHOR]

Knickzones are large rock outcrops found in upstream and middle plateau river basins. This kind of geological formation, which is considered a macrohabitat, creates a complex of mesohabitats: pools, riffles and runs, with distinct characteristics. In the present work, the aim was to evaluate the influence of connectivity and seasonality on the trophic structure of the ichthyofauna found in knickzone pools. Fish were sampled in four connected and three isolated pools, during dry and rainy seasons, and the stomach contents of 20 species were analyzed. Seasonal differences in diet occurred, with greater contribution of algae and aquatic hexapod in the dry season and of plant fragments and organic matter in the rainy season. The high diet overlap found in the isolated pools may be related to more intensive biotic interactions among individuals confined in physically restricted habitats. Seasonality in combination with connectivity to the main channel influenced the trophic structure of fish assemblage in the knickzone. Knickzones dynamics are modulated by seasonal events, such as floods, and connectivity of habitats, being extremely important for the trophic interactions between species. Alterations to these dynamics, like the construction of hydroelectric power plants, can modify significantly the trophic ecology of knickzones. [ABSTRACT FROM AUTHOR]

Seasonal variation in innate immunity is often attributed to either temporal environmental variation or to life‐history trade‐offs that arise from specific annual cycle stages but decoupling them is difficult in natural populations.Here, we effectively decouple seasonal environmental variation from annual cycle stage effects by exploiting cross‐seasonal breeding and moult in the tropical Common Bulbul Pycnonotus barbatus. We test how annual cycle stage interacts with a key seasonal environmental variable, rainfall, to determine immunity at population and individual level. If immune challenge varies with precipitation, we might expect immune function to be higher in the wet season due to increased environmental productivity. If breeding or moult imposes resource constraints on birds, depending on or independent of precipitation, we might expect lower immune indices during breeding or moult.We sampled blood from 818 birds in four annual cycle stage categories: breeding, moult, simultaneous breeding and moulting, or neither. We quantified indices of innate immunity (haptoglobin, nitric oxide (NOx) and ovotransferrin concentrations, and haemagglutination and haemolysis titres) over two annual cycles of wet and dry seasons.Environment (but not annual cycle stage or interactions between both) explained variation in all immune indices, except NOx. NOx concentration differed between annual cycle stages but not between seasons. However, within the wet season, haptoglobin, NOx, ovotransferrin and haemolysis differed significantly between breeding and non‐breeding females. Aside from some recorded inconsistencies, population level results were largely similar to results within individuals that were measured repeatedly. Unexpectedly, most immune indices were higher in the dry season and during breeding.Higher immune indices may be explained if fewer or poorer quality resources force birds to increase social contact, thereby exposing individuals to novel antigens and increased infection risk, independently of environmental productivity. Breeding birds may also show higher immunity if less immune‐competent and/or infected females omit breeding. We conclude that seasonal environmental variation impacts immunity more directly in natural animal populations than via resource trade‐offs. In addition, immune indices were more often variable within than among individuals, but some indices are characteristic of individuals, and so may offer selective advantages if heritable. Tropical environments are considered highly immune‐challenging for animals because of their relative higher organic productivity. However, this study from a seasonally arid tropical environment where annual cycle stages are decoupled from seasonal environmental variation, provides evidence that variation in innate immune function does not follow differences in annual cycle stages or simple environmental productivity pattern but may arise from interactions between individuals and their environment, and this may apply to variation in disease risk. [ABSTRACT FROM AUTHOR]

Highlights • Higher sex, adrenal and thyroid hormones levels in active than hibernation season. • Testosterone and estradiol peaks coincide in September, during reproductive season. • Progesterone in females peaks a month later than estradiol. • Seasonal changes of corticosterone suggest a role in mobilization of energy stores. • Spring T 3 surge occurs only in females; high energy investment in reproduction. Abstract The tegu lizard Salvator merianae is a large, widely distributed teiid lizard endemic to South America that exhibits annual cycles of high activity during the spring and summer, and hibernation during winter. This pattern of activity and hibernation is accompanied by profound seasonal changes in physiology and behavior, including endothermy during the austral spring. The unusual combination of seasonal endothermy, hibernation and oviparity, in a non-avian, non-mammalian species, makes S. merianae an interesting subject for study of comparative aspects of endocrine regulation of seasonal changes in physiology. In the present study, we first validated commercially available immunoassay kits for quantification of hormone concentrations of the reproductive (testosterone, estradiol and progesterone), adrenal (corticosterone), and thyroid [thyroxine (T 4) and triiodothyronine (T 3)] axes in plasma of an outdoor, captive adult male and female S. merianae in southeastern Brazil. All assays exhibited parallelism and accuracy with S. merianae plasma. We next assessed patterns of concentration of these hormones across the annual cycle of S. merianae. Testosterone in males and estradiol in females peaked in spring coincident with the peak in reproductive behavior. Progesterone in females was significantly elevated in October coincident with putative ovulation when gravid females build nests. Thyroid hormones, known for regulating energy metabolism, varied seasonally with some sex-dependent differences. T 4 gradually increased from an annual nadir during pre-hibernation and hibernation to high concentrations during spring in both sexes. In contrast, T 3 did not vary seasonally in males, but females showed a two-fold increase in T 3 during the spring reproductive season. T 3 may be involved in energy investment during the seasonal production of large clutches of eggs. Corticosterone was significantly elevated during the active season in both sexes, suggesting its involvement in mobilization of energy stores and modulation of behavior (territoriality) and physiology. Ours is the first investigation of concurrent changes in reproductive, thyroid and adrenal hormone concentrations in this endemic and physiologically unique South American lizard. Our findings set the stage for future investigations to determine the extent to which these hormones influence activity and thermoregulation in S. merianae. [ABSTRACT FROM AUTHOR]

The present study was conducted on the experimental animals, Macrobrachium dayanum (Henderson) (Crustacea: Decapoda) to analyze the seasonal changes in reproductive cycle of female, found at different locations in river Gomti (26°55'; 80°59' E), in and around Lucknow (U.P. India). The reproductive activities were found in cyclic manner in M.dayanum, which breeds continuously throughout the year but with two distinct peaks one major in the month of May-July and one minor in the month of January - Feburary. Five stages of Oogenesis i.e. proliferative, meiotic, previtellogenic, vitellogenic and resorbtion or atretic oocyte phase have been recorded in M. dayanum. Mature ova were noticed in two peaks i.e. major in month of July - August and September and minor in months of February and March. Histoarchitecture of hepatopancreas showed seasonal changes in accordance with the gonadal development. The reproductive cycle of M.dayanum is reported for the first time and very little work is known on the seasonal changes with respect to reproduction and its correlation with hepatopancreas. [ABSTRACT FROM AUTHOR]

The Caatinga, a Brazilian biome that covers an area of 740,000 km2, is characterized by semi-arid climatic conditions with high temperatures and irregular rains throughout the year. The present study verified the structure of the local bat community and the seasonal variation in the abundance of bats and their diversity. We sampled four points on Serra dos Macacos and Serra de Antenor, in the municipality of Tobias Barreto, Sergipe. Field campaigns were conducted monthly between February and November 2011 in the region of the Serra dos Macacos, with the same sampling effort being applied in the dry and rainy seasons. A total sampling effort of 95,040 m2⋅h resulted in the capture of 104 specimens, representing 15 species belonging to the families Phyllostomidae (12 sp.), Vespertilionidae (2 sp.) and Mormoopidae (1 sp.). The Jackknife 1 estimate indicated the occurrence of 21.3±2.07 species in the study area. There was no difference in species diversity between the two stations (t=0.65, p=0.51). The guild of frugivorous and nectarivorous bats were the most abundant in both seasons, and most representative in the rainy season. Significant seasonal difference was found in the abundance of bats between the dry and rainy seasons (χ2=16.96; df=1; p<0.05). The results were consistent with other Caatinga studies in terms of species richness and diversity, and community structure, with a predominance of nectarivorous bats and seasonal variation in the community structure. [ABSTRACT FROM AUTHOR]

The precipitation recharge coefficient (PRC) is an important parameter for regional water resource evaluations and groundwater numerical simulations. This parameter has evident seasonal variations due to seasonal differences of climatic and vegetation, especially in cold arid regions. While the annual mean value and spatial variability of PRC are reported commonly, fewer studies have focused on seasonal variations of PRC. Understanding seasonal variations of PRC is important for accurately assessing groundwater resources and interpreting the effect of vegetation and climate change on groundwater recharge. This study identifies and quantifies seasonal variations of PRC based on water-table fluctuation and hydrogen and oxygen stable isotopes (using an end-number mixing model) in the Ordos Plateau of Northwest China. The results show that PRCs in the cold season (October-March) are more than twice as high as in the warm season (April-September). The freeze-and-thaw processes of seasonally frozen soil lead to a lag in groundwater recharge processes as a response to precipitation infiltration, which should be considered when using PRC to evaluate groundwater recharge. The deep water mixing and the effect of the amount of precipitation on isotopic composition should be taken into consideration when the isotopic method is used to estimate PRC. [ABSTRACT FROM AUTHOR]

The reproductive pattern of the Libyan jird (Meriones libycus Lichtenstein, 1823) from central Saudi Arabia was investigated in the absence of rainfall. In this study, body mass, morphometry of the reproductive tract, the histology of the reproductive organs, and the hormone concentrations of males and females were studied over 12 consecutive months in a wild population of the Libyan jird from central Saudi Arabia. Previous studies have found the breeding season of the Libyan jird from the Sahara desert of Algeria to occur during the wet months of spring. In the absence of rainfall, temperature and photoperiod were found to be important activators of reproductive activity. The cooler temperatures and shorter days of winter triggered the onset of ovulation in females and increased testes size and seminiferous tubule diameter in males. Only two pregnancies were found during the sampling period, which occurred during the cooler winter and early spring and coincided with a rise in plasma progesterone concentration in females. The Libyan jird was found to shift its breeding to the cooler months of winter in the absence of rainfall. This study strengthens the findings that changes in rainfall and temperature in dry deserts are critical cues for the onset of reproduction in small mammals. [ABSTRACT FROM AUTHOR]

Given their large movement capacities, migratory birds have in principle a wide range of possible geographical locations for their breeding and non‐breeding destinations, yet each species migrates between consistent breeding and non‐breeding ranges. In this study, we use a macroecological approach to search for the general factors explaining the location of the seasonal ranges of migratory bird species across the globe. We develop a null model to test the hypotheses that access to resources, geographical distance, tracking of temperature, and habitat conditions (separately as well as considered together) have a major influence in the location of species' migratory destinations, once each species' geographical constraints are taken into account. Our results provide evidence for a trade‐off between costs associated with distance travelled and gains in terms of better access to resources. We also provide strong support to the hypotheses that all factors tested, with the exception of habitat, have a strong and additive effect on the global geography of bird migration. Indeed, our results indicate that species' contemporary migratory destinations (i.e. the combination of their breeding and non‐breeding ranges) are such that they allow species to track a temperature regime throughout the year, to escape local competition and reach areas with better access to resources, and to minimise the spatial distance travelled, within the limitations imposed by the geographical location of each species. Our study thus sheds light on the mechanisms underpinning bird migration and provides a strong basis for predicting how migratory species will respond to future change. [ABSTRACT FROM AUTHOR]

Highlights • Diurnal and seasonal variations in crop coefficients were developed for citrus orchards of central India. • Dual crop coefficient approach was performed considering soil-water balance and flux variance similarity theories. • Performance of the two models to partition ET fluxes was evaluated by comparing with direct measurements of E and T fluxes. • Variability in K cb between SIMDualKc and EC FP models are prominent during initial stage and gradually diminished with time. Abstract Accurate quantification of crop water demand and characterizing its temporal variability is essential in evaluating the role of water saving strategies for sustainable production. Representing evapotranspiration (ET) as a proxy to crop water needs is often misleading, particularly during the periods of high non-stomatal exchanges. This study is aimed at modeling crop water requirements for citrus orchards of central India using single and dual crop coefficient approaches. ET fluxes derived from eddy-covariance (EC) technique were used to develop single crop coefficient (K c) curves at daily, weekly, and seasonal scales. Site-specific K c values for initial, mid, and late season were found to be 0.43, 0.78, and 0.80 respectively. ET partitioning was done by estimating soil evaporation coefficient (K e), and basal crop coefficient in the presence of water stress (K s × K c b) using soil-water balance (SIMDualKc) and EC flux partitioning (EC FP) methods. SIMDualKc model was calibrated against electrical resistivity tomography (ERT) derived soil water contents (R2 = 0.81, RMSE = 0.021 cm3 cm−3). Energy based flux partitioning was done by considering the correlation between high-frequency water vapour and carbon fluxes and applying flux variance similarity principles. Direct measurement of evaporation (E) and transpiration (T) at four citrus trees (using micro-lysimeters and sap flow meters) was used to assess the performance of two models. Three-stage basal crop coefficients from SIMDualKc and EC FP methods were found to be 0.18, 0.57, 0.63 and 0.26, 0.51, 0.59 respectively. Both methods were effectively partitioning the ET fluxes at daily scale (R2 > 0.5, RMSE < 0.6 mm, NSE > 0.3), however, variability in estimated fluxes between the two methods is high during the initial stage and gradually diminished with time. [ABSTRACT FROM AUTHOR]

The role of environmental control and spatial structuring may vary depending on dispersal mode within a metacommunity in stream systems. However, as a result of high seasonal variation in environment conditions and phenological features, there might be considerable seasonal changes in the relative importance of structuring factors. The objective of this study was (i) to determine the relative role of structuring factors for aquatic macroinvertebrates with different dispersal mode groups which have seasonal variation in their dispersal capacity and (ii) to disentangle seasonal changes in metacommunity structuring. We sampled 50 stream sites of the Middle Danube Basin (Hungary) in spring and summer. We compared Distance-Decay Relationships between communities of different dispersal groups and distance measures, and then we used variation partitioning analysis and Moran's eigenvector maps based on overland and watercourse distances to reveal structuring processes in both seasons. We found that metacommunities of all dispersal groups were influenced in both seasons mainly by environmental factors with additional impacts of the spatial components. Our findings suggest that metacommunities of taxa with temporally stable dispersal capacity have seasonally stable structuring processes, while the relative importance of structuring factors can vary seasonally in groups with seasonally changing dispersal capacity. [ABSTRACT FROM AUTHOR]

Summary: Despite the importance of nonstructural carbohydrates (NSC) for growth and survival in woody plants, we know little about whole‐tree NSC storage. The conventional theory suggests that NSC reserves will increase over the growing season and decrease over the dormant season. Here, we compare storage in five temperate tree species to determine the size and seasonal fluctuation of whole‐tree total NSC pools as well as the contribution of individual organs.NSC concentrations in the branches, stemwood, and roots of 24 trees were measured across 12 months. We then scaled up concentrations to the whole‐tree and ecosystem levels using allometric equations and forest stand inventory data.While whole‐tree total NSC pools followed the conventional theory, sugar pools peaked in the dormant season and starch pools in the growing season. Seasonal depletion of total NSCs was minimal at the whole‐tree level, but substantial at the organ level, particularly in branches. Surprisingly, roots were not the major storage organ as branches stored comparable amounts of starch throughout the year, and root reserves were not used to support springtime growth.Scaling up NSC concentrations to the ecosystem level, we find that commonly used, process‐based ecosystem and land surface models all overpredict NSC storage. [ABSTRACT FROM AUTHOR]

Effects of seasonal variation, including entirely different pollutant concentrations and temperature, on microbial community structures in a municipal wastewater treatment plant (WWTP) with anaerobic/anoxic/oxic (A2/O) system have been evaluated through high-throughput sequencing technique. Venn diagrams and bacterial diversity indices indicated significantly decreased biodiversity in winter. However, microbial community structure analysis showed high consistency among different A2/O chambers in summer or winter, while nearly all the dominant bacteria in summer changed in winter. Moreover, decreased ammonia-oxidizing bacteria (0.7% in summer and 0.3% in winter) coupled with low temperature fitted with the lower ammonia removal efficiency in winter. Functional genes predicted by Phylogenetic Investigation of Communities by Reconstruction of Unobserved States indicated stability of their structures and contents in both summer and winter. These results suggested that seasonal variation would shift the microbial community structures, but not enough to change the functional genes. Results also provide a reference for the further study on microbial community structures of municipal WWTPs, especially with unstable performance. [ABSTRACT FROM AUTHOR]

Highlights • Developed a scallop production model coupling DEB and ROMS. • Successfully assessed carrying capacity in the largest scallop ranching in China. • Food and temperature are main factors determining optimal densities in studied area. Abstract A production model has been developed to estimate scallop bottom culture carrying capacity. The model coupled pelagic system, scallop energetics and population dynamics with hydrodynamics. The methodology considers temperature and particle organic carbon (POC) were used to determine the carrying capacity through scallop growth, production and economic benefit. The model was applied to the Zhangzidao culture area in the North Yellow Sea, the largest marine ranching of Japanese scallops Patinopecten yessoensis in China. The studied area was divided into four boxes according to the temperature and depth gradients. The results showed that the model could successfully capture the main characteristics of the observed environmental variables, POC concentrations and biological behaviour of the cultured scallops. The food availability showed seasonal variations. The low temperature had also a great effect on the growth of the scallops in the south area during period of January to July. In contrary, the high temperature would cause high mortality rate of the scallops in the north area in September. Based on the production and profit, the optimal seeding densities were estimated to be 82,500, 105,000, 82,500, 60,000 in. ha−1, respectively in the Boxes1, 2, 3 and 4. There is the potential to increase the seeding density in the northeast area (Box 2), while the southwest area has already exceeded its capacity. The successful application of the model suggests that it could be used as a management tool for estimating the production carrying capacity in the bottom culture systems. [ABSTRACT FROM AUTHOR]

Highlights • Can uncertainties of instantaneous FAPAR be assessed with Wireless Sensor Networks? • Observations reveal main sources of uncertainty of the two-flux FAPAR estimate. • FAPAR overestimation for large solar zenith angle and colored leaves was confirmed. • Wind speed was identified as another potential source of uncertainty. Abstract The estimation of the Fraction of Absorbed Active Radiation (FAPAR) and its uncertainties is key for understanding global carbon balances. This work investigates the variability and associated uncertainties of in-situ two-flux FAPAR observations attributed to changes in phenological and meteorological conditions. Specifically, we assessed influences of illumination conditions with solar zenith angle and the ratio of diffuse-to-total incident radiation, wind speed, leaf color and snow coverage on the variability of two-flux FAPAR. We assumed FAPAR acquired under diffuse light conditions to be closest to "true" FAPAR as it is not influenced by the solar zenith angle. To reveal the uncertainty of the two-flux FAPAR measurements, we investigated the difference (Δ two-flux) between FAPAR acquired under diffuse light conditions and two-flux FAPAR acquired during a certain environmental condition (e.g. large solar zenith angle). A positive (negative) value obtained from this difference was interpreted as an indication for an underestimation (overestimation) of "true" FAPAR by the two-flux FAPAR estimate, as found in previously investigations with canopy radiative transfer models (RTM). Therefore, permanent PAR measurements were carried out 2015–2017 in a sub-alpine, spruce-dominated forest in Southern Germany using a Wireless Sensor Network (WSN). FAPAR observations exhibited considerable seasonal variability (0.89 to 0.99 ± 0.03) despite the dominance of evergreen spruces. The in-situ observations confirm significant overestimation of FAPAR by up to 0.06 under solar zenith angles above 60° and by up to 0.05 during the presence of colored autumn leaves, similarly to the results obtained from previous studies with canopy RTMs. Additionally, our results indicate an effect of wind speed which we consider crucial at sites where high wind speeds occur more frequently. Overall, this study shows the potential of permanent WSN monitoring activities to ensure multi-year FAPAR observations with associated uncertainty information that are demanded to validate satellite-derived FAPAR products in forest ecosystems. [ABSTRACT FROM AUTHOR]

This study reveals information for the first time about the total lipid (TL) content and fatty acid composition (FA) of Mactra stultorum (M. corallina). Three edible organs (foot, mantle and adductor muscle) were the subjects of this research in order to determine the most favorable periods for their consumption in relation to seasonal variability. The results showed lower lipid content in the adductor muscles in summer (12.73 ± 2.55 mg/g dry matter); while a higher content was observed in winter (28.97 ± 3.50 mg/g dry matter). However, similar lipid contents were observed in the mantle and foot tissues among the seasons. The fatty acid composition of Mactra stultorum adductor muscles, mantle and foot was dominated by saturated fatty acids (SFA) and polyunsaturated fatty acids (PUFA). Palmitic acid (16:0) was the major saturated fatty acid (SFA) and reached higher levels during summer in the foot (26%), mantle (21%) and adductor muscles (25%). Among PUFA, eicosapentaenoic acid (EPA, 20:5n-3) and docosahexaenoic acid (DHA, 22:6n-3) showed significant variation among seasons with high levels recorded during winter and spring. Monounsaturated fatty acids (MUFA) did not show any remarkable variation among seasons for the three studied tissues. Seasonal changes in fatty acids were observed for all samples, reaching a maximum level in winter or spring. [ABSTRACT FROM AUTHOR]

Poison frogs acquire chemical defenses from the environment for protection against potential predators. These defensive chemicals are lipophilic alkaloids that are sequestered by poison frogs from dietary arthropods and stored in skin glands. Despite decades of research focusing on identifying poison frog alkaloids, we know relatively little about how environmental variation and subsequent arthropod availability impacts alkaloid loads in poison frogs. We investigated how seasonal environmental variation influences poison frog chemical profiles through changes in the diet of the Climbing Mantella (Mantella laevigata). We collected M. laevigata females on the Nosy Mangabe island reserve in Madagascar during the wet and dry seasons and tested the hypothesis that seasonal differences in rainfall is associated with changes in diet composition and skin alkaloid profiles of M. laevigata. The arthropod diet of each frog was characterized into five groups (i.e. ants, termites, mites, insect larvae, or ‘other’) using visual identification and cytochrome oxidase 1 DNA barcoding. We found that frog diet differed between the wet and dry seasons, where frogs had a more diverse diet in the wet season and consumed a higher percentage of ants in the dry season. To determine if seasonality was associated with variation in frog defensive chemical composition, we used gas chromatography / mass spectrometry to quantify alkaloids from individual skin samples. Although the assortment of identified alkaloids was similar across seasons, we detected significant differences in the abundance of certain alkaloids, which we hypothesize reflects seasonal variation in the diet of M. laevigata. We suggest that these variations could originate from seasonal changes in either arthropod leaf litter composition or changes in frog behavioral patterns. Although additional studies are needed to understand the consequences of long-term environmental shifts, this work suggests that alkaloid profiles are relatively robust against short-term environmental perturbations. [ABSTRACT FROM AUTHOR]

Jatropha curcas L. is a stem-succulent shrub that produces high concentrations of seed oils that are convertible into biodiesel. In this study, the incidence of four insect pests on Jatropha , Strabala rufa , Gnathamitermes tubiformans , Pempelia morosalis , and Acanthoplus discoidalis was recorded over three years in a semi-arid climate in Gaborone, Botswana. The occurrence of these insects was concentrated in the summer season from October to April, while lower numbers of all species were found in May as the temperature began to reduce towards the winter season, suggesting that insect pests of Jatropha exhibit a unique temporal pattern in this region. A considerable variation was observed among Jatropha accessions regarding the insect pest occurrence, indicating a vast difference in the susceptibility to insect pests among Jatropha accessions. [ABSTRACT FROM AUTHOR]

Abstract The annual succession of phytoplankton of the open waters of the Black Sea was investigated on the basis of a database covering the 30-year period from 1985 to 2014. Seasonal variations of the taxonomic composition were analysed with regard to weather conditions and the physical and chemical properties of the environment. Two different patterns of annual phytoplankton succession were revealed for the post-winter period from March to November. After cold winters a classical annual succession of diatoms → dinoflagellates → coccolithophores → dinoflagellates → diatoms was observed, whereas after regular winters another type of succession; dinoflagellates → dinoflagellates → coccolithophores → diatoms → diatoms, took place. These two successions corresponded to seasonal dynamics of nitrate concentration and its share in the total inorganic nitrogen. During cold years these parameters decreased from spring to summer with a subsequent increase in autumn, whereas in regular years they were unusually high in summer. The enigma of this summer nitrate enrichment is well explained by the hypothesis of increasing cross-shelf nutrient transport. During regular years, weak hydrodynamic forcing occurs throughout the year, resulting in a large number of mesoscale eddies along the shelf in summer–autumn that in turn cause the intense transport of coastal waters rich in nitrate to the Sea interior. Development of the large-celled diatom Pseudosolenia calcar-avis in the sea basin observed in summer is in line with this hypothesis. This mechanism was also confirmed by positive relationships between the high sea-surface temperature, and the low Ekman pumping velocity and mean kinetic energy of currents in winter on the one hand, and the contribution of diatoms to the total phytoplankton biomass in summer–autumn, on the other. A case study of mesoscale eddies in the open waters in summer–autumn demonstrated a shift in species composition to large-celled diatoms inside these structures. Climate warming observed during the last 25 years resulted in a decrease in the frequency of cold winters from 30% to 15%, which has led to a decline in the annual phytoplankton standing stock. Thus, in the Black Sea, climate warming affects phytoplankton not directly by an increase in temperature, but by a decrease in the frequency of cold winters. Highlights • Winter weather defines two different patterns of annual phytoplankton succession in the Black Sea. • Cross-shelf advection of inorganic nitrogen controls the taxonomic composition of phytoplankton. • Decrease of frequency of cold winters affects phytoplankton phenology and standing stock. [ABSTRACT FROM AUTHOR]

Highlights • We evaluated factors affecting overlap between pilot whales and pelagic longlines. • Most overlap and bycatch occurred near the 1000 m isobaths. • Seasonal shifts in fishing effort strongly influenced bycatch rates. • Distribution of observer effort may influence observed bycatch rates. • Spatial management strategies could be effective in reducing bycatch. Abstract Short-finned pilot whales (Globicephala macrorhynchus) depredate pelagic longlines along the shelf break of the Mid-Atlantic Bight. The mortality and serious injury of short-finned pilot whales in the U.S. pelagic longline fishery recently exceeded Potential Biological Removal levels defined under the U.S. Marine Mammal Protection Act, and bycatch mitigation techniques developed to date have been unsuccessful. We examine the spatial and temporal characteristics of pilot whale habitat use and longline fishing effort, quantify spatiotemporal patterns of pilot whale bycatch based on environmental factors, and assess the potential for a spatial management approach to mitigate pilot whale bycatch. We assess patterns of overlap and bycatch of pilot whales and longlines by applying Area Under the Curve and Williamson's Spatial Overlap Index analyses to telemetry data from short-finned pilot whales, along with longline fishing effort and Pelagic Observer Program (POP) fisheries observer data from 2014 and 2015. We found that proximity to the 1000 m isobath, season, and sea surface temperature (SST) were important variables influencing pilot whale-longline overlap and POP bycatch rates. Pilot whale density was consistently highest immediately inshore of the 1000 m isobath, but longline effort varied seasonally relative to the 1000 m isobath. Resultant seasonal patterns in pilot whale-longline overlap relative to the 1000 m isobath were strongly and significantly correlated with POP bycatch rates; the highest bycatch rates primarily occurred in fall and winter months, when longline effort shifted inshore near the 1000 m isobath. We observed differences in the distribution of logbook and POP longline sets relative to the 1000 m isobath; POP sets were more dispersed relative to this feature while the overall distribution of longline effort was typically focused at the 1000 m isobath. Since bycatch primarily occurred close to the 1000 m isobath, more bycatch might be observed if the observer effort better reflected the overall distribution of longline effort. In winter months, POP bycatch occurred in cooler waters than most observations of tagged pilot whales, and therefore the relationship between bycatch and SST during winter months requires further exploration. Together, our results suggest that a spatial management approach could be effective in reducing pilot whale bycatch in the pelagic longline fishery, and an improved understanding of the relationships between pilot whale bycatch and dynamic variables might allow high-risk regions for pilot whale bycatch to be further delineated. [ABSTRACT FROM AUTHOR]

Highlights • The timing of river use by a euryhaline fish differed along a latitudinal gradient. • A common gear type, in this case electrofishing, allowed for cross-site comparisons. • Seasonal habitat use was likely driven by changes in hydrology and temperature. • This type of work can lead to predictions of where a species' range may expand. Abstract Plasticity in life-history traits and behaviors allows organisms to track spatial environmental variation, such as that resulting from a latitudinal gradient. In estuaries, hydrological patterns can vary greatly with latitude, causing variable habitat use patterns across a species' range. For Common Snook (Centropomus undecimalis) a large euryhaline fish, seasonal movements between the open estuary and freshwater reaches of rivers have been documented. We hypothesized that the timing of river use by Snook would be driven primarily by the magnitude of freshwater inflow, except at the northern limit of its range where lethal water temperatures may be a stronger influence. Data from electrofishing studies (2012–2016) conducted in rivers associated with four estuaries along a latitudinal gradient in western Florida were compared for seasonal differences in Snook abundance using negative binomial regression. In rivers of southwestern Florida (those in Everglades and Charlotte Harbor), Snook abundances increased three-fold during the time of year when surface waters inundating floodplains recede and force prey into the main stems of rivers. These hydrologically driven processes, and surges in Snook abundance, occurred during spring in the Everglades and fall in rivers of Charlotte Harbor. In Tampa Bay rivers, which have less freshwater inflow than the rivers farther south, Snook abundance differed little between seasons. In spring-fed rivers north of Tampa Bay, Snook abundances in fall and winter were twice those of spring and summer; stable water temperatures were thought to provide thermal refuge at the northernmost range of Snook. This work illustrates how the timing of habitat use by a species, and the underlying reasons, can differ greatly among sites. It also demonstrates the value of cross-site comparisons in providing for a more complete understanding of how a species uses available habitats across its range. [ABSTRACT FROM AUTHOR]

Abstract Saccharides are important constituents in atmospheric aerosols but studies in northwestern China are still very limited. Here, we have measured anhydrosugars (levoglucosan, mannosan and galactosan), primary sugars (glucose, fructose, sucrose and trehalose), and sugar alcohols (arabitol, mannitol, sorbitol and inositol) in ambient PM 2.5 samples during summer and winter in Xi'an city, northwestern China. The abundance of total saccharides showed no clear seasonal variation, but apparent distinctions on the levels of the three categories and individual saccharide compounds were found. Primary sugars and particularly sucrose were dominant in summer. In contrast, levoglucosan was the predominant species in winter, contributing 60% of total saccharides. Source apportionment by positive matrix factorization revealed that airborne pollen was a major source of PM 2.5 associated-saccharides in summer, accounting for 35% of total saccharides; while biomass burning activities contributed to 60% of the winter saccharides. Furthermore, an increasing trend of biomass/biofuel burning contribution to winter PM 2.5 was observed in comparison with previous studies in Xi'an, suggesting a change in emission sources may be underway in northwestern China. Graphical abstract Unlabelled Image Highlights • Sucrose dominates total saccharides during summer while levoglucosan was the dominant species during winter. • Biomass burning emissions are the predominant source of saccharides in winter. • A yearly increase of biomass burning contribution to PM 2.5 during winter was found over Xi'an. [ABSTRACT FROM AUTHOR]

The reproductive cycles of turtles are linked to environmental factors, such as photoperiod and temperature. Currently, the reproductive physiology of diamondback terrapins (Malaclemys terrapin) is poorly understood, especially in Gulf of Mexico. The reproductive cycles of terrapins are thought to follow typical seasonal patterns. However, latitudinal variations in temperature regimens lead to longer-lasting warm periods, which can facilitate extended reproductive periods in some turtle species. This suggests that terrapins may show a similar change in the southern parts of their range. To elucidate aspects of the terrapin reproductive cycle, we sampled during the known reproductive season of a southern population of terrapins (May-July), as well as during the winter in late December and early January. We used enzymelinked immunosorbent assays to quantify concentrations of the plasma sex hormones estradiol and testosterone, and the egg yolk protein precursor vitellogenin. Additionally, we used radiography and ultrasonography to monitor the ovarian status and egg development in females. Follicles showed no significant difference in average diameter across sampling periods with preovulatory class follicles existing in both summer and winter. Eggs were only detected from May to July, with radiographic data showing second clutches in 4 individuals. Testosterone and estradiol showed elevated concentrations throughout the nesting season, coinciding with multiple clutches of eggs, before both showed a significant decrease in winter. Vitellogenin showed peak concentrations in June with other months showing lower but detectable concentrations. Our results suggest that in southwestern Florida, terrapins may have extended reproductive potential and continuous vitellogenic cycles given the presence of preovulatory follicles and high quantities of vitellogenin found in summer and winter. However, true continuous reproduction was not detected in this study. [ABSTRACT FROM AUTHOR]

Growth and development rates in many insects are affected by photoperiod, which enables insects to synchronize their life histories with seasonal events, but this aspect of insect photoperiodism remains understudied. Here we use several experimental combinations of constant day length and temperature to determine whether there are quantitative developmental responses to photoperiod in the bug Scantius aegyptius and leaf beetle Timarcha tenebricosa. The thermal ecology of these two species is strikingly different: the former is thermophilic and active throughout summer and the latter is spring-active and avoids the hottest time of the year. In accordance with their contrasting natural thermal environments, S. aegyptius survives better and achieves a larger fi nal body mass at the high experimental temperatures, while T. tenebricosa survives better and is heavier at the low experimental temperatures. Despite this polarity, long-day conditions accelerate larval development relative to a shortday photoperiod in both species, and this developmental response is stronger at low temperatures. Our re-visitation of previous literature in light of the new fi ndings indicates that this similarity in photoperiodic response is superficial and that relatively faster development in midsummer is likely to have a different ecological role in summer- and spring-active species. In the former, it may allow completion of an additional generation during the favourable season, whereas in the latter, this acceleration likely ensures that the larval stage, which is vulnerable to heat, is completed before the onset of hot weather. [ABSTRACT FROM AUTHOR]

Stem CO 2 efflux (E S ) plays an essential role in the carbon balance of forest ecosystems. Therefore, it is necessary to study the vertical and seasonal variations in E S in forests with different ages, especially in response to factors associated with temperature, nutrients and wood structure. In this study, we investigated E S and its association with temperature factors using a carbon flux system (Li-8100A) at monthly intervals during the growing season (May to September) and the non-growing season (October) from 2013 to 2015. In addition, we collected data on nutrients and wood structure in August 2016 from 16- (young), 25- (immature), and 41-year-old (mature) Larix principis-rupprechtii Mayr stands in North China. Our analysis showed that the E S values at stem positions near the crown and the root system were generally higher than those in the middle and that the minimum E S values in July occurred at 2.0 m (3.61 μmol m −2 s −1 ), 3.0 m (2.42 μmol m −2 s −1 ), and 5.0 m (4.03 μmol m −2 s −1 ) in the young, immature, and mature forests, respectively. Air temperature and wood temperature influenced the vertical variation in E S , as did stem nitrogen concentration and sapwood width. Compared to the method that uses the vertical E S gradient to determine tree-scale CO 2 effluxes for 16-, 25- and 41-year-old L. principis-rupprechtii forests, the method that uses the E S value at the 1.3-m stem position underestimated the CO 2 effluxes by 5%, 6%, and 24%, respectively. The E S and Q 10 models for each stem position for the three forest ages in this study can be used to accurately estimate tree-scale CO 2 effluxes. These results not only clarified the relationships between the vertical variation in E S and temperature, nutrient content and wood structure, but also revealed the likely response mechanisms of E S to these factors. Methodologically, incorporating the vertical variation in E S and the associated drivers into conventional models would improve the accuracy of annual E S estimates. [ABSTRACT FROM AUTHOR]