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1. Spread rates of a juvenile-adult population in constant and temporally variable environments

Author:
Huang, Qihua; Zhang, Yuxiang
Source:
Theoretical ecology 2021 v.14 no.1 pp. 145-160
ISSN:
1874-1738
Subject:
seasonal variation,   etc   ; ecology; equations; invasive species; models;     Show all 5 Subjects
Abstract:
... The question of how growth, dispersal, and environmental factors affect the persistence and spread of an invasive species is of great importance in spatial ecology. Motivated by the fact that in a species, different development stages may have different vital rates and dispersal characteristics, we propose and study a reaction-diffusion juvenile-adult model, which is a natural extension of the cla ...
DOI:
10.1007/s12080-020-00485-4

2. Transformation pathways of arsenic species: SRB mediated mechanism and seasonal patterns

Author:
Shi, Wenjing; Song, Wenjie; Luo, Yu; Qile, Geer; Zheng, Jinli; Lü, Changwei; He, Jiang
Source:
Chemosphere 2021 v.263 pp. 128255
ISSN:
0045-6535
Subject:
seasonal variation,   etc   ; arsenic; pyrite; sulfates; summer;     Show all 5 Subjects
Abstract:
... Sulfate reducing bacteria (SRB) mediated reduction plays a key role in the biological cycling of As, which inherently associates with the transformation of As species. However, the potential pathways of As species transformation, the predominant driving process and their explanatory factors regulating seasonal As mobility mediated by SRB remains poorly understood. This study explored the possible ...
DOI:
10.1016/j.chemosphere.2020.128255

3. Saponin contents in the starfish Echinaster sepositus: Chemical characterization, qualitative and quantitative distribution

Author:
Dahmoune, Bouchra; Bachari-Houma, Fouzia; Chibane, Mohamed; Jéhan, Philippe; Guegan, Jean-Paul; Dahmoune, Farid; Aissou-Akrour, Cherifa; Mouni, Lotfi; Ferrières, Vincent; Hauchard, Didier
Source:
Biochemical systematics and ecology 2021 v.96 pp. 104262
ISSN:
0305-1978
Subject:
seasonal variation,   etc   ; Asteroidea; cecum; chemotaxonomy; ecology; integument; saponins; stomach; summer;     Show all 9 Subjects
Abstract:
... In this study, we report the inter-organ, the sexual and the seasonal variability, of saponins contained in the common Mediterranean starfish Echinaster (Echinaster) sepositus. Saponins were extracted from five distinct body components namely the stomach, the pyloric caeca, the gonads, the oral body wall and aboral body wall. Of both sexes (males and females) collected at different seasons, the sa ...
DOI:
10.1016/j.bse.2021.104262

4. Field and laboratory experiments on the seasonal variation of the locomotor activity patterns in the desert terrestrial isopod Hemilepistus reaumurii

Author:
Ayari, Anas; Jelassi, Raja; Ghemari, Chedliya; Nasri-Ammar, Karima
Source:
Biological rhythm research 2021 v.52 no.5 pp. 688-701
ISSN:
1744-4179
Subject:
seasonal variation,   etc   ; Isopoda; biological rhythms; laboratories; locomotion; spring; summer; winter;     Show all 8 Subjects
Abstract:
... The locomotor activity pattern of the desert woodlouse Hemilepistus reaumurii was monitored over the four seasons in nature and in the laboratory. Results showed that the activity of this species was mostly concentrated during the day in nature as well as under controlled laboratory conditions. Moreover, two main peaks around sunrise and sunset described this activity; this bimodality was clearer ...
DOI:
10.1080/09291016.2019.1600269

5. Seasonal Changes in Structure and Dynamics in an Urbanized Salt Wedge Estuary

Author:
McKeon, Margaret A.; Horner-Devine, Alexander R.; Giddings, Sarah N.
Source:
Estuaries and coasts 2021 v.44 no.3 pp. 589-607
ISSN:
1559-2723
Subject:
seasonal variation,   etc   ; asymmetry; estuaries; river flow; rivers; salinity; urbanization;     Show all 7 Subjects
Abstract:
... Hydrographic measurements of salt wedge structure and dynamics spanning a 20-fold seasonal range of river discharges are used to investigate the seasonal variability in the strongly stratified Duwamish River Estuary. The effect of river discharge on salt wedge length, stratification, pycnocline thickness, and intratidal differences in salinity structure are evaluated. The salt wedge decreases in l ...
DOI:
10.1007/s12237-020-00788-z

6. Age and seasonal pattern of contagious agalactia in small ruminants in Ukraine

Author:
Bohach, Dmytro Mykolaivych; Stegniy, Borys Tymofiyovych; Bohach, Mykola Volodymyrovych; Pavlov, Serhii Leonidovych; Bolotin, Vitaliy Igorovych
Source:
Journal of Veterinary Research 2021 v.65 no.1 pp. 67-72
ISSN:
2450-8608
Subject:
seasonal variation,   etc   ; Mycoplasma agalactiae; agalactia; lactation; pathogens; veterinary medicine; Ukraine;     Show all 7 Subjects
Abstract:
... The aim of the study was to determine how the spread of contagious agalactia in sheep and goats in the Odesa region depended on the age of the animals and the season. From January 2016 to December 2018, 1,964 ewes and 1,484 nanny goats of different age groups were studied by ELISA for antibodies to Mycoplasma agalactiae. The highest incidence of contagious agalactia was registered in one-year-old ...
DOI:
10.2478/jvetres-2021-0014

7. Seasonal patterns and spatial variation of Borrelia burgdorferi (sensu lato) infections in Ixodes ricinus in the Netherlands

Author:
Hartemink, Nienke; van Vliet, Arnold J. H.; Gort, Gerrit; Gassner, Fedor; Jacobs, Frans; Fonville, Manoj; Takken, Willem; Sprong, Hein
Source:
Parasites & vectors 2021 v.14 no.1 pp. 121
ISSN:
1756-3305
Subject:
seasonal variation,   etc   ; Borrelia burgdorferi; Ixodes ricinus; Lyme disease; autumn; risk; spring; summer; Netherlands;     Show all 9 Subjects
Abstract:
... BACKGROUND: The incidence of Lyme borreliosis varies over time and space through as yet incompletely understood mechanisms. In Europe, Lyme borreliosis is caused by infection with a Borrelia burgdorferi (s.l.) genospecies, which is primarily transmitted by a bite of Ixodes ricinus nymphs. The aim of this study was to investigate the spatial and temporal variation in nymphal infection prevalence of ...
DOI:
10.1186/s13071-021-04607-7

8. Inconsistent seasonal variation of antibiotics between surface water and groundwater in the Jianghan Plain: Risks and linkage to land uses

Author:
Liu, Xi; Wang, Zhi; Zhang, Lu; Fan, Weiying; Yang, Chao; Li, Enhua; Du, Yun; Wang, Xuelei
Source:
Journal of environmental sciences (China) 2021 v.109 pp. 102-113
ISSN:
1001-0742
Subject:
seasonal variation,   etc   ; clarithromycin; groundwater; pollution; risk assessment; summer; surface water; winter; China;     Show all 9 Subjects
Abstract:
... Antibiotics are widely used in humans and animals, but their transformation from surface water to groundwater and the impact of land uses on them remain unclear. In this study, 14 antibiotics were systematically surveyed in a complex agricultural area in Central China. Results indicated that the selected antibiotic concentrations in surface waters were higher in winter (average: 32.7 ng/L) than in ...
DOI:
10.1016/j.jes.2021.03.002

9. Use of selected NSAIDs in Guangzhou and other cities in the world as identified by wastewater analysis

Author:
Yan, Jingna; Lin, Wenting; Gao, Zhihan; Ren, Yuan
Source:
Chemosphere 2021 v.279 pp. 130529
ISSN:
0045-6535
Subject:
seasonal variation,   etc   ; acetaminophen; diclofenac; epidemiology; ibuprofen; municipal wastewater; summer; wastewater treatment; watersheds; winter; China;     Show all 11 Subjects
Abstract:
... The mass load of pharmaceuticals in the municipal wastewater based on wastewater-based epidemiology (WBE) is a good indication of population consumption in the catchment. After successful application of illicit drugs’ estimation, this method holds the potential to measure the geographical and temporal consumption of prescription medicines. In this study, we investigated the occurrence of four non- ...
DOI:
10.1016/j.chemosphere.2021.130529

10. Rethinking tracer-based (Ra, Rn, salinity) approaches to estimate point-source submarine groundwater discharge (SGD) into coastal systems

Author:
Savatier, Maxime; Rocha, Carlos
Source:
Journal of hydrology 2021 v.598 pp. 126247
ISSN:
0022-1694
Subject:
seasonal variation,   etc   ; freshwater; groundwater; oceans; radium; radon; river flow; salinity; time series analysis; Ireland;     Show all 10 Subjects
Abstract:
... Submarine groundwater discharge (SGD) has been shown to potentially be a more important source of solutes to the global ocean than river flow. As a result, the accuracy of predictions of the magnitude and seasonal variability of SGD to the sea is critical for the management of coastal marine ecosystems. For a model site (Kinvarra Bay, Ireland) dominated by point source SGD inputs, we show that the ...
DOI:
10.1016/j.jhydrol.2021.126247

11. New approach for obtaining the C-factor of RUSLE considering the seasonal effect of rainfalls on vegetation cover

Author:
Fonseca de Carvalho, Daniel; Macedo, Pietro Menezes Sanchez; Oliveira, Paulo Tarso Sanches; Antunes, Mauro Antonio Homem; Durigon, Valdemir Lucio; Fidalgo, Elaine Cristina Cardoso
Source:
International soil and water conservation research 2021 v.9 no.2 pp. 207-216
ISSN:
2095-6339
Subject:
seasonal variation,   etc   ; rain; research; soil; soil erosion; vegetation cover; water conservation; watersheds; Brazil;     Show all 9 Subjects
Abstract:
... We present a new approach for calculating the C-factor of RUSLE considering the effect of low-reflectance vegetation cover areas on the reduction of the effects on erosion caused by rainfall seasonality. For this, we propose the coefficients Cr2 (rescaled 2) and C-PC (Precipitation Correction), which represent the C-factor, and an adaptation in NDVI calculation, according to the seasonality of pre ...
DOI:
10.1016/j.iswcr.2020.12.001

12. Selection and evaluation of a septage management concept for islands: The case study of Brač Island

Author:
Margeta, Jure
Source:
Journal of environmental management 2021 v.285 pp. 112128
ISSN:
0301-4797
Subject:
seasonal variation,   etc   ; case studies; circular economy; environmental management; issues and policy; sewage systems; tourism;     Show all 7 Subjects
Abstract:
... This paper analyses the problem of septage mining on islands in accordance with the circular economy (CE) concept. Islands are natural and socioeconomic systems wherein seasonal tourism and agriculture are the major economic activities, while environmental and health security are the top priorities. The majority of the individual housing facilities on islands are not connected to a public sewage s ...
DOI:
10.1016/j.jenvman.2021.112128

13. Determination of interest in vitamin use during COVID-19 pandemic using Google Trends data: Infodemiology study

Author:
Çimke, Sevim; Yıldırım Gürkan, Dilek
Source:
Nutrition 2021 v.85 pp. 111138
ISSN:
0899-9007
Subject:
seasonal variation,   etc   ; COVID-19 infection; ascorbic acid; autumn; pandemic; spring; vitamin E;     Show all 7 Subjects
Abstract:
... The aim of this study was to determine the interest in vitamin use during the COVID-19 pandemic usıng Google Trends data.Searches were made between January 1, 2016 and August 30, 2020. First, the word “vitamin” was searched. Additionally, the search words "vitamin,” “COVID-19,” “immunity,” and Vitamin D,” “Vitamin C,” “Vitamin E,” and “Vitamin A” were searched comparatively. Search was made in Tur ...
DOI:
10.1016/j.nut.2020.111138

14. Seasonal implications of the benthic ecological status assessment in a protected Mediterranean coastal lagoon: Stagno Longu of Posada (Sardinia, Italy)

Author:
Orro, Cristina; Cabana, David
Source:
Regional studies in marine science 2021 v.44 pp. 101759
ISSN:
2352-4855
Subject:
seasonal variation,   etc   ; basins; biodiversity; coastal water; humans; indicator species; marine science; multivariate analysis; sediments; Italy; Sardinia;     Show all 11 Subjects
Abstract:
... Understanding how biotic indicators respond to natural variability is essential for the health state evaluation of the benthic ecosystems. This study analysed the composition and structure of the benthic communities in the coastal lagoon Stagno Longu of Posada (Sardinia) to investigate the seasonal response of the biological indicator M-AMBI. Multivariate analysis and biodiversity descriptors show ...
DOI:
10.1016/j.rsma.2021.101759

15. Effects of pruning intensity on nonstructural carbohydrates of Populus alba × P. talassica in the arid desert region of Northwest China

Author:
Zhang, Jun; Liu, Liqing
Source:
Journal of forestry research 2021 v.32 no.2 pp. 823-830
ISSN:
1007-662X
Subject:
seasonal variation,   etc   ; Populus alba; forestry; leaves; pruning; research; starch; sugars; tree height; trees; China;     Show all 11 Subjects
Abstract:
... Although pruning is important to obtain high-quality, large-diameter timber, the effects of pruning on nonstructural carbohydrates (NSC) in aboveground organs of many timber species are not well understood. Three intensities of pruning (none, moderate and severe) were tested on poplars (Populus alba × P. talassica) in the arid desert region of northwest China to compare the concentrations of solub ...
DOI:
10.1007/s11676-020-01098-7

16. Males and females of a polygamous songbird respond differently to mating opportunities

Author:
Zheng, Jia; Komdeur, Jan; Székely, Tamás; Versteegh, Maaike A.; Li, Donglai; Wang, Hui; Zhang, Zhengwang
Source:
Behavioral ecology and sociobiology 2021 v.75 no.4 pp. 72
ISSN:
0340-5443
Subject:
seasonal variation,   etc   ; Remiz; decline; divorce; ecology; females; humans; males; parental behavior; polygamy; progeny; sociobiology; songbirds;     Show all 13 Subjects
Abstract:
... Parents are expected to make fine-tuned decisions by weighing the benefits of providing care to increase offspring survival against that of deserting to pursue future mating opportunities. A higher incentive for the rarer sex in the population indicates an impact of mating opportunities on parental care decisions. However, in a dynamic breeding system, deserting the offspring and searching for a n ...
DOI:
10.1007/s00265-021-03000-9

17. Seasonal variation and COVID-19 infection pattern: A gap from evidence to reality

Author:
Rayan, Rehab A.
Source:
Current opinion in environmental science & health 2021 v.20 pp. 100238
ISSN:
2468-5844
Subject:
seasonal variation,   etc   ; COVID-19 infection; environmental science; health services; humidity; influenza; pandemic; public health; temperature; China;     Show all 10 Subjects
Abstract:
... In December 2019, the coronavirus disease (COVID-19) was discovered in China, causing many cases and deaths. Several studies have explored the role of environmental factors in the spread of COVID-19, emphasizing the effect of two weather parameters, humidity and temperature. Those parameters are evidently vital in affecting outbreaks of infectious respiratory diseases, like influenza; yet, such an ...
DOI:
10.1016/j.coesh.2021.100238

18. Transmission networks and ectoparasite mite burdens in Oecomys paricola (Rodentia: Cricetidae)

Author:
Fernandes, Fernanda Rodrigues; da Silva Abreu, Somayra; Cruz, Leonardo Dominici
Source:
Parasitology 2021 v.148 no.4 pp. 443-450
ISSN:
1469-8161
Subject:
seasonal variation,   etc   ; Cricetidae; dry season; ectoparasites; habitats; mites; parasite load; parasitology; rodents; savannas; wet season; Brazil;     Show all 12 Subjects
Abstract:
... The host contact network structure results from the movement and behaviour of hosts (e.g. degree of sociability; vagility and greater or lesser fidelity of shelters), which can generate heterogeneity in the transmission of parasites and influence the parasitic burden of individual hosts. In the current study, we tested the hypothesis that the burdens of Gigantolaelaps oudemansi mites are related t ...
DOI:
10.1017/S0031182020002231

19. Altitudinal migration of insects

Author:
Kimura, Masahito T.
Source:
Entomological science 2021 v.24 no.1 pp. 35-47
ISSN:
1343-8786
Subject:
seasonal variation,   etc   ; age structure; altitude; autumn; dormancy; estivation; mark-recapture studies; migratory behavior; spring; summer; temperature;     Show all 11 Subjects
Abstract:
... A number of insects have been suggested to perform seasonal migration between low‐ and high‐altitude areas. In these insects, support for the occurrence of migration mainly came from observations that focal insects disappeared from a certain range of altitudes but appeared at different altitudes with short time lags. In some insects, further support was obtained by mark–recapture studies, analyses ...
DOI:
10.1111/ens.12444

20. Glucocorticoid levels predict subsequent social tactic in females of a facultatively social mammal

Author:
Hill, Davina L.; Pillay, Neville; Schradin, Carsten
Source:
Functional ecology 2021 v.35 no.3 pp. 650-662
ISSN:
0269-8463
Subject:
seasonal variation,   etc   ; body condition; corticosterone; energy; females; phenotype; social structure; testosterone;     Show all 8 Subjects
Abstract:
... Facultatively social species, in which individuals can switch between group‐ and solitary‐living tactics, offer an opportunity to shed light on proximate mechanisms underlying alternative life histories. Promising hormonal mediators of social tactic include glucocorticoids, which control energy allocation and are negatively related to body condition, and testosterone which regulates numerous socia ...
DOI:
10.1111/1365-2435.13744