scholarly journals Vertical and seasonal variations in soil CO2 production in a 55-year-old oriental arborvitae (Platycladus orientalis) plantation in China

2016 ◽  
Vol 92 (04) ◽  
pp. 477-486 ◽  
Author(s):  
Zhiping Fan ◽  
Zhihua Tu ◽  
Yanbin Qin ◽  
Fayun Li
Keyword(s):  
Seasonal Variations ◽  
Seasonal Pattern ◽  
Coniferous Forest ◽  
Northern China ◽  
Vertical Gradient ◽  
Co2 Production ◽  
Platycladus Orientalis ◽  
Clear Seasonal Pattern ◽  
Different Depths ◽  
Soil Co2 Production

The aim of this work was to explore the vertical and seasonal variations of CO2 within the soil profile based on Fick’s law of diffusion in an oriental arborvitae plantation. We continuously measured the soil CO2 concentration profile using CO2 sensors buried at different depths in a coniferous forest in northern China and calculated the CO2 flux based on the profile measurements using a dynamic model. The diurnal pattern of CO2 concentration and flux fluctuated during the day and varied less at night. The CO2 profile had a vertical gradient, with the highest concentrations in the deepest soil layers. The CO2 flux had a clear seasonal pattern with a maximum in summer and a minimum in winter. The contributions of the H, A, B, and C horizons to the total CO2 flux were 75.38, 13.52, 7.61, and 3.49%, respectively. Q10 was 2.668, 4.469, 1.175, and 3.333 in the H, A, B, and C horizons, respectively. The CO2 flux determined from the concentration profiles agreed well with the CO2 flux measured by open dynamic chambers, suggesting that this model could be used to successfully measure soil CO2 emissions and to describe the processes underlying CO2 efflux.

scholarly journals Aspekte van die anatomie, morfologie en ververing van die kroonkiewiet Vanellus coronatus

1992 ◽  
Vol 11 (1) ◽  
pp. 4-8
Author(s):  
P. C. Anderson ◽  
O. B. Kok
Keyword(s):  
Seasonal Variations ◽  
Seasonal Pattern ◽  
Fat Content ◽  
The Body ◽  
Body Measurements ◽  
Liver Mass ◽  
Clear Seasonal Pattern ◽  
One Year

Aspects of the anatomy and morphology of crowned plovers (Vanellus coronatus) collected over a period of one year at the J.B.M. Hertzog (Bloemfontein) and B.J. Vorster (Kimberley) airports were investigated. The renewal of plumage in both sexes apparently takes place mainly during the summer months. Except for some bill dimensions, all standard body measurements of adult and immature males are significantly larger than those of females. No clear seasonal pattern could be distinguished in the body and liver mass of the birds. Seasonal variations in the visible fat content of adult crowned plovers of both sexes are probably related to breeding activities and the availability of food.

scholarly journals Scyphomedusae and Ctenophora of the Eastern Adriatic: Historical Overview and New Data

Diversity ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 186
Author(s):  
Branka Pestorić ◽  
Davor Lučić ◽  
Natalia Bojanić ◽  
Martin Vodopivec ◽  
Tjaša Kogovšek ◽  
...  
Keyword(s):  
Adriatic Sea ◽  
Seasonal Pattern ◽  
Geographical Location ◽  
Distribution Patterns ◽  
Mnemiopsis Leidyi ◽  
Future Studies ◽  
Phenological Data ◽  
Pelagia Noctiluca ◽  
Regional Trends ◽  
Clear Seasonal Pattern

One of the obstacles to detecting regional trends in jellyfish populations is the lack of a defined baseline. In the Adriatic Sea, the jellyfish fauna (Scyphozoa and Ctenophora) is poorly studied compared to other taxa. Therefore, our goal was to collect and systematize all available data and provide a baseline for future studies. Here we present phenological data and relative abundances of jellyfish based on 2010–2019 scientific surveys and a “citizen science” sighting program along the eastern Adriatic. Inter-annual variability, seasonality and spatial distribution patterns of Scyphomedusae and Ctenophore species were described and compared with existing historical literature. Mass occurrences with a clear seasonal pattern and related to the geographical location were observed for meroplanktonic Scyphomedusae Aurelia solida, Rhizostoma pulmo, and to a lesser extent Chrysaora hysoscella, Cotylorhiza tuberculata and Discomedusa lobata. Holoplanktonic Pelagia noctiluca also formed large aggregations, which were seasonally less predictable and restricted to the central and southern Adriatic. Four species of Ctenophora produced blooms limited to a few areas: Bolinopsis vitrea, Leucothea multicornis, Cestum veneris and the non-native Mnemiopsis leidyi. However, differences between Adriatic subregions have become less pronounced since 2014. Our results suggest that gelatinous organisms are assuming an increasingly important role in the Adriatic ecosystem, which may alter the balance of the food web and lead to harmful and undesirable effects.

scholarly journals A New Methodology for Estimating the Surface Temperature Lapse Rate Based on Grid Data and Its Application in China

2018 ◽  
Vol 10 (10) ◽  
pp. 1617 ◽  
Author(s):  
Yun Qin ◽  
Guoyu Ren ◽  
Tianlin Zhai ◽  
Panfeng Zhang ◽  
Kangmin Wen
Keyword(s):  
Surface Temperature ◽  
Land Surface ◽  
North China ◽  
Seasonal Pattern ◽  
Regional Climate ◽  
Regional Climate Change ◽  
Vertical Gradient ◽  
Lapse Rate ◽  
Grid Data ◽  
Temperature Lapse Rate

Land surface temperature (LST) is an important parameter in the study of the physical processes of land surface. Understanding the surface temperature lapse rate (TLR) can help to reveal the characteristics of mountainous climates and regional climate change. A methodology was developed to calculate and analyze land-surface TLR in China based on grid datasets of MODIS LST and digital elevation model (DEM), with a formula derived on the basis of the analysis of the temperature field and the height field, an image enhancement technique used to calculate gradient, and the fuzzy c-means (FCM) clustering applied to identify the seasonal pattern of the TLR. The results of the analysis through the methodology showed that surface temperature vertical gradient inversion widely occurred in Northeast, Northwest, and North China in winter, especially in the Xinjiang Autonomous Region, the northern and the western parts of the Greater Khingan Mountains, the Lesser Khingan Mountains, and the northern area of Northwest and North China. Summer generally witnessed the steepest TLR among the four seasons. The eastern Tibetan Plateau showed a distinctive seasonal pattern, where the steepest TLR happened in winter and spring, with a shallower TLR in summer. Large seasonal variations of TLR could be seen in Northeast China, where there was a steep TLR in spring and summer and a strong surface temperature vertical gradient inversion in winter. The smallest seasonal variation of TLR happened in Central and Southwest China, especially in the Ta-pa Mountains and the Qinling Mountains. The TLR at very high altitudes (>5 km) was usually steeper than at low altitudes, in all months of the year.

scholarly journals A cross-sectional study of factors affecting seasonality in bipolar disorder

2014 ◽  
Vol 20 (2) ◽  
pp. 2 ◽  
Author(s):  
Pankaj Kumar Mittal ◽  
Shubham Mehta ◽  
Ram Kumar Solanki ◽  
Mukesh Kumar Swami ◽  
Parth Singh Meena
Keyword(s):  
Bipolar Disorder ◽  
Seasonal Variations ◽  
Affective Disorders ◽  
Seasonal Pattern ◽  
Cross Sectional Study ◽  
Sectional Study ◽  
Cross Sectional ◽  
Factors Affecting ◽  
Behavioural Patterns ◽  
Assessment Questionnaire

<p><strong>Background.</strong> Researchers have evinced interest in the effect of seasonal variations on mood and behavioural patterns in affective disorders. </p><p><strong>Objective. </strong>To study seasonality in bipolar disorder (BD) patients and also the factors affecting this seasonality. </p><p><strong>Method. </strong>Forty-nine patients with BD in euthymic phase were recruited and analysed using<strong> </strong>the<strong> </strong>Seasonal Pattern Assessment Questionnaire and Morningness-Eveningness Questionnaire. </p><p><strong>Results. </strong>Most of the patients were morning types but chronotype had no influence on seasonality. Age of patient and number of episodes were the most important factors affecting seasonality in BD. </p><p><strong>Conclusion. </strong>Seasonality and its influencing factors must be considered while managing bipolar disorder.</p>

scholarly journals Seasonal variations in aerosol optical properties over China

2008 ◽  
Vol 8 (3) ◽  
pp. 8431-8453 ◽  
Author(s):  
Y. Wang ◽  
J. Xin ◽  
Z. Li ◽  
S. Wang ◽  
P. Wang ◽  
...  
Keyword(s):  
Tibetan Plateau ◽  
Seasonal Variations ◽  
Rural Areas ◽  
Meteorological Data ◽  
Agricultural Practices ◽  
Hainan Island ◽  
Northern China ◽  
The Tibetan Plateau ◽  
Northern Forest ◽  
Aerosol Emissions

Abstract. The seasonal variations in background aerosol optical depth (AOD) and aerosol type are investigated over various ecosystems in China based upon three years' worth of meteorological data and data collected by the Chinese Sun Hazemeter Network. In most parts of China, AODs are at a maximum in spring or summer and at a minimum in autumn or winter. Minimum values (0.10~0.20) of annual mean AOD at 500 nm are found in the Qinghai-Tibetan Plateau, which is located in the remote northeast corner of China, the northern forest ecosystems and Hainan Island. Annual mean AOD ranges from 0.25 to 0.30 over desert and oasis areas as well as the desertification grasslands in northern China; the annual mean AOD over the Loess Plateau is moderately high at 0.36. Regions where the highest density of agricultural and industrial activities are located and where anthropogenic sulphate aerosol and soil aerosol emissions are consistently high throughout the whole year (e.g. the central-eastern, southern and eastern coastal regions of China) experience annual mean AODs ranging from 0.50~0.80. Remarkable seasonal changes in the main types of aerosol over northern China (characterized by the Angstrom exponent, α) are seen. Due to biomass and fossil fuel burning from extensive agricultural practices in northern rural areas, concentrations of smoke and soot aerosols rise dramatically during autumn and winter (high α), while the main types of aerosol during spring and summer are dust and soil aerosols (low α). Over southeast Asia, biomass burning during the spring leads to increases in smoke and soot emissions. Over the Tibetan Plateau and Hainan Island where the atmosphere is pristine, the main types of aerosol are dust and sea salt, respectively.

scholarly journals INDICADORES ECOLÓGICOS DE LA ESTRUCTURA DE LA COMUNIDAD FITOPLANCTÓNICA EN BAHÍA CONCEPCIÓN, GOLFO DE CALIFORNIA, MÉXICO

2010 ◽  
Vol 25 (2) ◽  
pp. 95
Author(s):  
G. Verdugo-Díaz ◽  
A. Martínez-López ◽  
I. Gárate-Lizárraga
Keyword(s):  
Water Column ◽  
Gulf Of California ◽  
Phytoplankton Community ◽  
Seasonal Pattern ◽  
Warm Season ◽  
Phytoplankton Abundance ◽  
Important Group ◽  
Clear Seasonal Pattern ◽  
High Species Richness ◽  
Phytoplankton Size

Se presentan los cambios en la distribución espacial de la comunidad fitoplanctónica en Bahía Concepción, B.C.S. de 1991 a 1993. Se estimó la abundancia total, la variación espacio-temporal por fracciones de tamaño (nano y microfitoplancton) y se describe su estructura. Se determinaron 235 taxa, en donde las diatomeas fueron el grupo con mayor riqueza de especies (131). Los géneros más importantes fueron Chaetoceros, Rhizosolenia y Nitzschia. El segundo grupo en importancia fue el de los dinoflagelados (92 especies), representados principalmente por Protoperidinium, Ceratium y Prorocentrum; el tercer grupo fueron los silicoflagelados (9 especies), principalmente del genero Dictyocha. Las diatomeas dominaron en la temporada fría cuando la columna de agua se mantiene homogénea, en tanto que los dinoflagelados prosperaron durante la temporada cálida cuando la columna de agua estuvo estratificada. De este último grupo, 10 especies son tóxicas o potencialmente tóxicas. La abundancia fitoplanctónica total no mostró un comportamiento estacional definido, sin embargo, las variaciones interanuales mostraron un decremento de aproximadamente 25% durante 1992 y 1993, asociado con anomalías positivas de temperatura. A pesar de que las abundancias totales disminuyeron, la contribución porcentual de la fracción nanofitoplanctónica se mantuvo. Ecological indicators of the phytoplankton community structure in Bahía Concepción, Gulf of California, Mexico Seasonal changes in the spatial distribution of the phytoplankton community were determined in Bahía Concepción, B.C.S., from 1991 to 1993. The total abundance and the seasonal variations of phytoplankton size fractions (nanno and microphytoplankton) as well as its structure were determined. A total of 235 taxa were identified. Diatoms were the best represented group due to their high species richness (131). The most important genera were Chaetoceros, Rhizosolenia and Nitzschia. The second important group were dinoflagellates (92 species), represented mainly by Protoperidinium, Ceratium and Prorocentrum. The third numerically important group were the silicoflagellates (9 species). The most representative genus of this group was Dictyocha. A major presence of the diatoms was observed during the cold months with a homogeneous water-column. Major presence of dinoflagellates was recorded during the warm season when the water-column appeared stratified. Ten species of dinoflagellates were considered as toxic or potentially toxic. Total phytoplankton abundance did not show a clear seasonal pattern; nevertheless, the interannual variations exhibited an important decline of about 25 % during 1992 and 1993. These changes were related to positive anomalies of temperature. Altough phytoplankton abundance diminished, the percentage contribution of nannophytoplankton was stable.

scholarly journals A meridional structure of static stability and ozone vertical gradient around the tropopause in the Southern Hemisphere extratropics

2010 ◽  
Vol 10 (8) ◽  
pp. 19175-19194 ◽  
Author(s):  
Y. Tomikawa ◽  
T. Yamanouchi
Keyword(s):  
Southern Hemisphere ◽  
Seasonal Variations ◽  
Inversion Layer ◽  
Polar Vortex ◽  
Vertical Gradient ◽  
Static Stability ◽  
Radiative Heating ◽  
Stratospheric Polar Vortex ◽  
Close Relationship ◽  
The Antarctic

Abstract. An analysis of the static stability and ozone vertical gradient in the ozone tropopause based (OTB) coordinate is applied to the ozonesonde data at 10 stations in the Southern Hemisphere (SH) extratropics. The tropopause inversion layer (TIL) with a static stability maximum just above the tropopause shows similar seasonal variations at two Antarctic stations, which are latitudinally far from each other. Since the sunshine hour varies with time in a quite different way between these two stations, it implies that the radiative heating due to solar ultraviolet absorption of ozone does not contribute to the seasonal variation of the TIL. A meridional section of the static stability in the OTB coordinate shows that the static stability just above the tropopause has a large latitudinal gradient between 60° S and 70° S in austral winter because of the absence of the TIL over the Antarctic. It is accompanied by an increase of westerly shear with height above the tropopause, so that the polar-night jet is formed above this latitude region. This result suggests a close relationship between the absence of the TIL and the stratospheric polar vortex in the Antarctic winter. A vertical gradient of ozone mixing ratio, referred to as ozone vertical gradient, around the tropopause shows similar latitudinal and seasonal variations with the static stability in the SH extratropics. In a height region above the TIL, a small ozone vertical gradient in the midlatitudes associated with the Antarctic ozone hole is observed in a height region of the subvortex but not around the polar vortex. This is a clear evidence of active latitudinal mixing between the midlatitudes and subvortex.

Seasonal changes of steroid concentrations in seminal plasma of a European wild boar

1984 ◽  
Vol 107 (3) ◽  
pp. 425-427 ◽  
Author(s):  
D. Schopper ◽  
J. Gaus ◽  
R. Claus ◽  
H. Bader
Keyword(s):  
Wild Boar ◽  
Seminal Plasma ◽  
Seasonal Pattern ◽  
Plasma Concentrations ◽  
Boar Taint ◽  
Steroid Production ◽  
European Wild Boar ◽  
Clear Seasonal Pattern ◽  
Boar Semen ◽  
Low Levels

Abstract. The influence of season on testicular steroid production as a parameter of testicular function has been studied in a wild boar. Semen was collected once weekly while it served the dummy. In seminal plasma concentrations of the following steroids were determined by radioimmunoassay: unconjugated testosterone, conjugated testosterone, unconjugated total oestrogens, conjugated total oestrogens and 5α-androst-16-en-3-one ('boar-taint steroid'). All steroids showed a clear seasonal pattern with highest concentrations in autumn and early winter and low levels from January to July. Maxima during the rutting season were 10–25 times greater than average values out of season. During a 2-month-period (mid-July until mid-September) libido was abolished and the wild boar refused to mount the dummy. These results indicate that the seasonal variation in testicular steroid production by the wild boar, regulated by photoperiod, are similar to those of the domestic boar.

scholarly journals Spatial and Seasonal Variations of Standardized Photosynthetic Parameters under Different Environmental Conditions for Young Planted Larix olgensis Henry Trees

Forests ◽  
2018 ◽  
Vol 9 (9) ◽  
pp. 522 ◽  
Author(s):  
Qiang Liu ◽  
Fengri Li
Keyword(s):  
Environmental Conditions ◽  
Seasonal Variations ◽  
Seasonal Pattern ◽  
Repeated Measurements ◽  
Seasonal Patterns ◽  
Photosynthetic Parameters ◽  
Relative Depth ◽  
Larix Olgensis ◽  
Vertical Variations ◽  
Larix Olgensis Henry

Understanding the spatial and seasonal variations in leaf physiology is critical for accurately modeling the carbon uptake, physiological processes and growth of entire canopies and stands. For a 17-year-old Larix olgensis Henry plantation, vertical whorl-by-whorl sampling and analyses of seasonally repeated measurements of major photosynthetic parameters were conducted, and the correlations between photosynthetic parameters and environmental conditions, leaf morphological traits and spatial position within the crown were analyzed. According to the correlations, the photosynthetic parameters were standardized based on the environmental conditions to avoid the influence of the changing environment on the patterns of spatial and seasonal variations of photosynthetic parameters. The results showed that the standardized light-saturated net photosynthetic rate (SPmax), standardized dark respiration (SRd) and standardized stomatal conductance under saturated light (Sgs-sat) were all negatively related to the relative depth into the crown (RDINC) throughout the growing season. However, their vertical patterns were different during the development of the phenological phase. In addition, different gradients of environmental conditions also influenced the values and the range of the vertical variation in photosynthesis. High temperature and low humidity usually resulted in smaller values and weaker vertical variations of SPmax and Sgs-sat, but larger values and more obvious vertical variations in SRd. SPmax and Sgs-sat usually exhibited a parabolic seasonal pattern in different vertical positions within the crown; however, SRd generally followed a concave pattern. These seasonal patterns were all weaker with increasing RDINC. Different environments also exhibited a significant influence on the seasonal patterns of photosynthesis. We suggested that standardization is necessary before analyzing spatial and seasonal variations. A single environmental condition could not represent the spatial and seasonal patterns under all gradients of the environment. Spatial and seasonal variations should be simultaneously analyzed because they are related to each other.

Clinical Features and Epidemiology of Invasive Kingella kingae Infections in Southern Israel

PEDIATRICS ◽  
1993 ◽  
Vol 92 (6) ◽  
pp. 800-804
Author(s):  
Pablo Yagupsky ◽  
Ron Dagan ◽  
Charles B. Howard ◽  
Menachem Einhorn ◽  
Imad Kassis ◽  
...  
Keyword(s):  
Tract Infection ◽  
Respiratory Tract ◽  
Septic Arthritis ◽  
Respiratory Tract Infection ◽  
Seasonal Pattern ◽  
Invasive Infection ◽  
Upper Respiratory Tract ◽  
Kingella Kingae ◽  
Clear Seasonal Pattern ◽  
Hand Involvement

Objective. To characterize the clinical spectrum and epidemiology of invasive Kingella kingae infections in children living in southern Israel. Design. Five-year observational, descriptive study. Population. Children in whom K. kingae was isolated from blood or other normally sterile body fluid. Results. Twenty-five patients with invasive K. kingae infection (13 male and 12 female) were identified. Twenty-four of these children were younger than 2 years. The annual incidence was 14.3, 27.4, and 31.9 cases per 100 000 children ≤4 years, ≤24 months, and ≤12 months, respectively. Seventeen (68%) of 25 patients sought treatment between July and December. Concomitant upper respiratory tract infection or stomatitis was observed in 14 (56%) of the patients, suggesting a respiratory or buccal source for the infection. Four children were bacteremic: 2 of them suffered from a lower respiratory tract infection, and the remaining 2 had bacteremia with no evident focal infection. Twenty-one children had skeletal infections and none of them was bacteremic; 16 had septic arthritis, 3 had osteomyelitis, 1 had both osteomyelitis and septic arthritis of the adjacent joint, and 1 had dactylitis of the hand. Involvement of the ankle was unusually frequent among children with septic arthritis, whereas the calcaneus was involved in 3 of the 4 children with osteomyelitis. Antibiotic treatment resulted in full recovery in all cases, and only 2 patients with septic arthritis required surgical drainage. Conclusion. Kingella kingae is a much more common cause of invasive infection in young children than has been previously recognized. The disease has a clear seasonal pattern, usually affects the skeletal system, frequently involves unusual bones and joints, and follows a benign course.

Sign in / Sign up

Export Citation Format

Share Document