Minimum In October Research Articles

Characteristics of Atmospheric Dust Fall Pollution and Its Chemical Composition and Mass Reconstruction in Mentougou District of Beijing

To study the characteristics of atmospheric dust fall pollution in Mentougou District of Beijing, the monthly average monitoring results of 57 atmospheric dust fall samples from two state-controlled ambient air stations in Mentougou District from 2018 to 2022 were collected, and the atmospheric dust fall pollution status and its time variation characteristics in Mentougou District were analyzed. In order to explore the characteristics of chemical components of atmospheric dust fall and the results of quality mass reconstruction and their sources, 57 dust fall samples were collected using the active suction method at the Sanjiadian State-controlled Ambient Air Station. The mass concentration of dust fall and its chemical components were measured, the characteristics of chemical components in atmospheric dust fall were studied, and the mass reconstruction of the main components of atmospheric dust fall was performed using particle mass reconstruction technology. The reliability of the mass reconstruction results and the reasons for its undetermined components were also discussed. The results showed that from 2018 to 2022, the monthly dust fall in Mentougou District of Beijing changed periodically, being the maximum in April or May in spring and the minimum in October or November in autumn, and the maximum monthly dust fall was 3.2 to 8.4 times the minimum monthly dust fall. The order of the quarterly average monthly dust fall was as follows:spring>summer>autumn>winter, and the dust fall mainly came from spring and summer, accounting for 40.1%-43.0% and 23.8%-37.5% of the total annual dust fall, respectively. The annual average monthly dust fall in Mentougou District of Beijing showed a significant downward trend. The dust fall in 2022 had decreased by 52.8% compared with that in 2018, with an average annual decline of 13.2%, which was related to the improvement in the fine management level of urban environmental protection in Beijing in recent years. In 2021, soil dust had a significant impact on dust fall in Mentougou District, with an actual contribution of 44.2%. The chemical components in the atmospheric dust fall in Mentougou District were mainly water-soluble ions, crustal elements, organic carbon(OC), and elemental carbon(EC). The total mass of the measured chemical components accounted for 65.0% of the mass fraction of the dust fall. The secondary organic carbon(SOC) was also an important component of the atmospheric dust fall, and its mass concentration was 13.5 μg·m-3, accounting for 96.4% of the mass fraction of OC. The main components of atmospheric dust fall mass reconstruction were crust element fugitive dust, organic matter(OM), SO42-, NO3-, NH4+, trace elements, EC, and Cl-, with mass concentrations of 34.8, 28.0, 20.6, 15.0, 5.6, 4.3, 3.2, and 2.2 μg·m-3, accounting for 25.5%, 20.6%, 15.1%, 11.1%, 4.1%, 3.2%, 2.3%, and 1.6% of the dust fall quality, respectively. The atmospheric dust fall mainly came from the soil dust, construction cement dust, biomass combustion, waste incineration, and secondary transformation process. The measured mass concentration of atmospheric dust fall had a good correlation with the reconstructed mass concentration of chemical components, and the determination coefficient R2 was 0.8173. The undetermined components in the mass reconstruction results accounted for 16.5% of the dust fall mass, of which the particle bound water(PBW) in the dust fall accounted for 6.2% of the dust fall mass, and the remaining undetermined components might have been related to the unmeasured components, the selected estimation coefficient of OM and crustal elemental dust, the particle size composition, the selected chemical component analysis method, and its measurement error.

Seasonal Eddy Variability in the Northwestern Tropical Atlantic Ocean

Abstract Eddies in the northwestern tropical Atlantic Ocean play a crucial role in transporting the South Atlantic Upper Ocean Water to the North Atlantic and connect the Atlantic and the Caribbean Sea. Although surface characteristics of those eddies have been well studied, their vertical structures and governing mechanisms are much less known. Here, using a time-dependent energetics framework based on the multiscale window transform, we examine the seasonal variability of the eddy kinetic energy (EKE) in the northwestern tropical Atlantic. Both altimeter-based data and ocean reanalyses show a substantial EKE seasonal cycle in the North Brazil Current Retroflection (NBCR) region that is mostly trapped in the upper 200 m. In the most energetic NBCR region, the EKE reaches its minimum in April–June and maximum in July–September. By analyzing six ocean reanalysis products, we find that barotropic instability is the controlling mechanism for the seasonal eddy variability in the NBCR region. Nonlocal processes, including advection and pressure work, play opposite roles in the EKE seasonal cycle. In the eastern part of the NBCR region, the EKE seasonal evolution is similar to the NBCR region. However, it is the nonlocal processes that control the EKE seasonality. In the western part of the NBCR region, the EKE magnitude is one order of magnitude smaller than in the NBCR region and shows a different seasonal cycle, which peaks in March and reaches its minimum in October–November. Our results highlight the complex mechanisms governing eddy variability in the northwestern tropical Atlantic and provide insights into their potential changes with changing background conditions.

Adaptability of MODIS Daily Cloud-Free Snow Cover 500 m Dataset over China in Hutubi River Basin Based on Snowmelt Runoff Model

Global warming affects the hydrological characteristics of the cryosphere. In arid and semi-arid regions where precipitation is scarce, glaciers and snowmelt water assume important recharge sources for downstream rivers. Therefore, the simulation of snowmelt water runoff in mountainous areas is of great significance in hydrological research. In this paper, taking the Hutubi River Basin in the Tianshan Mountains as the study area, we used the “MODIS Daily Cloud-free Snow Cover 500 m Dataset over China” (MODIS_CGF_SCE) to carry out the Snowmelt Runoff Model (SRM) simulation and evaluated the simulation accuracy. The results showed that: (1) The SRM preferably simulated the characteristics of the average daily flow variation of the Hutubi River from May to October, from 2003–2009. The monthly total runoff was maximum in July and minimum in October. Extreme precipitation events influenced the formation of flood peaks, and the interannual variation trend of total runoff from May to October was increased. (2) The mean value of the volume difference (DV) during the model validation period was 8.85%, and the coefficient of determination (R2) was 0.73. In general, the SRM underestimates the runoff of the Hutubi River, and the simulation accuracy is more accurate in the normal water period than in the high-water period. (3) By analyzing MODIS_CGF_SCE from 2003 to 2009, areas above 3200 m elevation in the Hutubi River Basin were classified as permanent snow areas, and areas below 3200 m were classified as seasonal snow areas. In October, the snow area in the Hutubi River Basin gradually increased, and the increase in snow cover in the permanent snow area was greater than that in the seasonal snow area. The snowmelt period was from March to May in the seasonal snow area and from May to early July in the permanent snow area, and the minimum snow cover was 0.7%.

A time series assessment of terrestrial water storage and its relationship with hydro-meteorological factors in Gilgit-Baltistan region using GRACE observation and GLDAS-Noah model

Mountains regions like Gilgit-Baltistan (GB) province of Pakistan are solely dependent on seasonal snow and glacier melt. In Indus basin which forms in GB, there is a need to manage water in a sustainable way for the livelihood and economic activities of the downstream population. It is important to monitor water resources that include glaciers, snow-covered area, lakes, etc., besides traditional hydrological (point-based measurements by using the gauging station) and remote sensing-based studies (traditional satellite-based observations provide terrestrial water storage (TWS) change within few centimeters from the earth’s surface); the TWS anomalies (TWSA) for the GB region are not investigated. In this study, the TWSA in GB region is considered for the period of 13 years (from January 2003 to December 2016). Gravity Recovery and Climate Experiment (GRACE) level 2 monthly data from three processing centers, namely Centre for Space Research (CSR), German Research Center for Geosciences (GFZ), and Jet Propulsion Laboratory (JPL), System Global Land Data Assimilation System (GLDAS)-driven Noah model, and in situ precipitation data from weather stations, were used for the study investigation. GRACE can help to forecast the possible trends of increasing or decreasing TWS with high accuracy as compared to the past studies, which do not use satellite gravity data. Our results indicate that TWS shows a decreasing trend estimated by GRACE (CSR, GFZ, and JPL) and GLDAS-Noah model, but the trend is not significant statistically. The annual amplitude of GLDAS-Noah is greater than GRACE signal. Mean monthly analysis of TWSA indicates that TWS reaches its maximum in April, while it reaches its minimum in October. Furthermore, Spearman’s rank correlation is determined between GRACE estimated TWS with precipitation, soil moisture (SM) and snow water equivalent (SWE). We also assess the factors, SM and SWE which are the most efficient parameters producing GRACE TWS signal in the study area. In future, our results with the support of more in situ data can be helpful for conservation of natural resources and to manage flood hazards, droughts, and water distribution for the mountain regions.

Total Electron Content (TEC) estimation over Pakistan from local GPS network using spherical harmonics

Many organizations allow GNSS users to access Global Ionosphere Maps (GIMS). However, the TEC estimates derived from GIMs are of insufficient quality to describe small-scale TEC variations over Pakistan. In this paper, the first local TEC map over Pakistan for the year 2019, derived from a regional GPS network, is presented. Spherical harmonics expansion is employed to estimate TEC with the spatial resolution of latitude 0.2° x longitude 0.2° and temporal resolution of 5 minutes. The impact of changing the degree/order of harmonics is assessed and it is determined that harmonic expansion up to 6 degrees is sufficient for estimating accurate TEC map for the region of interest. We have demonstrated that the TEC maps of Pakistan generated by local model conform better to the GIM by Center of Orbit Determination (CODE) (RMS = 5.83) as compared to International Reference Ionosphere (IRI-2016) (RMS = 7.18). We found that the TEC estimated by the local model shows a better correlation to measured TEC; CODE-GIM overestimated TEC, while IRI-2016 underestimates it. Moreover, it was observed that TEC peaks during noon (1100-0100 LT) and Equinox (April). The residuals of local TEC estimates with respect to TEC obtained from CODE- GIM indicate the inaccuracy of CODE-GIM over the region of Pakistan: highest deviation of TEC from local model with respect to CODE –GIM was observed in April (RMS = 8.73) and minimum in October (RMS = 2.78). We have also analyzed the performance of our maps in geomagnetically disturbed days. The research presented in this paper will contribute towards the ionosphere study over Pakistan, where limited research is available currently.

Monitoring Vegetation Patterns at the Syrdarya River Basin from 2000 to 2015 using MODIS Data

The dependence of vegetation condition dynamics as expressed by Normalized Difference Vegetation Index (NDVI) from hydro-climatic factors (Multiyear precipitation, land surface temperature) in the Syrdarya River Basin (SRB) was analyzed for the period of 16 years from 2000 to 2015. The analysis demonstrated a different correlation between NDVI and hydrometric parameters. According to experimental analyses, the average NDVI values reached a maximum in April and minimum in October, while the annual average values of land surface temperature were observed maximum in June and minimum in October. Correlation between precipitation and NDVI was positive and extraordinarily strong in Spring while the correlation between Land Surface Temperature (LST) and NDVI was found negative and strong. Correlation between LST and NDVI changed from positive in spring to negative in summer due to an increase in seasonal temperature and found a decrease of vegetation cover throughout the Syrdarya river basin. Desert vegetation area in plain part of SRB decreased while NDVI of cropland area in Syrdarya and Shu river basins remained the same or increased. Hydro-climatic factors negatively affected a decrease in vegetation cover, which leads to desertification processes.

POPULATION STRUCTURE AND DRIFTING PATTERN OF AQUATIC MITES IN RANDI GAD, A TRIBUTARY OF RIVER ALAKNANDA IN GARHWAL HIMALAYA, UTTARAKHAND, INDIA

The present paper deals with the population structure and temporal drift pattern study of aquatic mites in Randi gad, which is a third order spring fed tributary of river Alaknanda in Garhwal, Uttarakhand, India. The mites contribute significantly to the structure and function of a stream ecosystem as it is a preferred food of fish and insects. To significantly analyze the drift strength of mites in a stream, a new index, Dobriyal Bahuguna Drifting Index (DBDI) has been developed which is based on the density of mite population in nature and number of drifting individuals in unit time. The maximum mite population in the stream was observed in January (51 units.m-2 ) and minimum in October (35 units.m-2 ) with 7 species. It was found that the mites perform specific monthly and diel drift pattern. Various factors like current velocity, breeding, colonization, habitat disturbance and protection from predators are responsible for it. The DBDI value for different mite species was observed highest in February (0.264) and minimum in November (0.227). It was also observed that maximum drift was preferred during late morning hours (8-12 hrs).

Feeding habits of oriental sole (Brachirus orientalis) on the Bushehr coast of the Persian Gulf

Abstract The feeding habits of oriental sole, Brachirus orientalis (Bloch & Schneider) were investigated using 300 male and female specimens collected from coastal waters of Bushehr Province (Persian Gulf) between June 2015 and July 2016. The total length of females and males ranged from 16.2 to 38.5 cm and 14.1 to 29.1 cm, respectively. Of the total number of stomachs examined, 225 were empty (vacuity index = 77%). This index varied significantly over the year (P < 0.05), with maximum values in April and September and minimum in October and May. The B. orientalis diet was composed of nine prey species belonging to five classes. The most important prey items were Crustacea and Mollusca (Bivalvia and Gastropoda). Diet composition showed little seasonal variation, and Crustacea, Bivalvia, and Gastropoda were the most important prey items in all seasons. Sex did not appear to have any significant effects on dietary composition, and the main prey items were consumed by both males and females (P > 0.05).

Performance analysis of 954,809 kWp PV array of Sheikh Zayed solar power plant (Nouakchott, Mauritania)

Amid all renewable energies, solar PV is of particular interest, mainly in Africa. Mauritania is an example of African countries which, gives great concern to produce electricity via PV installations. This study is carried out on the performance evaluation of a 954,809 kWp photovoltaic array made up of micro-amorphous silicon situated in Nouakchott (capital of Mauritania) at Sheikh Zayed solar power plant. The measures of one year of operation from September 2014 to August 2015 were evaluated according to the IEC 61724. The results obtained demonstrate that the photovoltaic array performances depend on both insolation and environmental conditions. The array capture loss ranges vary from a minimum value of 1.63 h/day to a maximum value of 2.46 h/day. So, the system loss is relatively stable, with an average value of 0.12 h per day. The monthly performance ratio varies from 0.61% in August to 0.71% in November, with a monthly average value of 0.66%. The monthly average capacity factor achieves its maximum and minimum in October (20.54%) and January (11.66%), respectively. The energy generated by the PV array (Edc) and the energy fed to the utility grid (Eac) during November moth, are affected by the insolation and the module temperature. However, wind speed variation does not influence those energies. Two linear models, depending on insolation and module temperature, are proposed for the evaluation of Edc and Eac during this month. These laters present a coefficient of determination (R2) of 0.96.

Water requirement of rice crop using CROPWAT model for Dehradun district, Uttarakhand

Management of water resources with optimal utilization results in fulfilling the constraint of inadequate water availability. Determination of crop water requirement is the first step in planning and effective utilization of irrigation water which curtaining the impact developed due to water stress condition. In the present study crop water requirement (CWR) and irrigation requirement was computed for rice in Dehradun district using CROPWAT simulation software by taking into account different local climatic parameter which influencing reference crop evapotranspiration (ET0) and thus affecting crop production. Penman–Monteith method was used to calculate ET0 and the United States Department of Agriculture (USDA) soil conservation method was used to estimate the effective rainfall. The ET0 varied from 1.43 (January) to 5.28 (May) mm/day and annual mean was 3.1 mm/day. The average annual rainfall value was 1718 mm and out of which 977.3 mm was effective rainfall. The crop water requirement and net irrigation water requirement (NIR) for rice crop was estimated to be 559.5 mm and 288.7 mm, respectively. The values of CWR and NIR were maximum in June and minimum in October. The net scheme irrigation requirement was scheduled to be maximum in June (190.6 mm/month), minimum in October month and zero in the month of July, August and September. The actual irrigated area was found to be 18.92 km2 for which net irrigation demand was maximum in the month of June (3.61 MCM) followed by October month (0.12 MCM). Total net irrigation demand for actual irrigated area was 5.47 MCM. The computation of crop water requirement, NIR, and total net irrigation demand using CROPWAT has proved to be an effective tool for proper management of water resources in water stress condition.

Seasonal variability of the Mindanao Current determined using mooring observations from 2010 to 2014

A mooring was deployed east of Mindanao Island at 8°N, 127°3′E from December 2010 to August 2014 to collect direct measurements of the Mindanao Current (MC). The Acoustic Doppler Current Profiler (ADCP) fixed on the main float shows that the MC is a strong and stable southward flow with a standard deviation less than 21 cm/s in the upper 500 m. The core flows between depths of 50 and 100 m with a maximum mean speed of 78 cm/s at 100 m. The seasonal variability of MC varies interannually and is depth-dependent. Although it takes a double-peak structure in the upper 200 m with two maxima in April and June and one minimum in October, the MC velocity has its maximum during boreal summer (June) and a minimum in autumn (September) when a 100-day low-pass filter is applied to remove intraseasonal signals. The semiannual signals are mainly limited between 200 and 350 m. The Asian monsoon intensifies the wind-driven sea-surface height anomaly (SSHA) east of Mindanao Island, and the resulting sharp slope induces meridional flow with large variability. Rossby waves and the boundary effect weaken the contribution of wind, stabilizing the flow of MC. The MC is determined by the zonal gradient of the SSHA rather than the SSHA itself, suggesting a possible inconsistency in seasonality between the Mindanao Eddy (ME) and MC. The semiannual ME signal plays an important role in the seasonal variability of MC.

Temporal and Spatial Variability and Trend Investigation of Total Ozone Column over Iraq Employing Remote Sensing Data: 1979-2012

The objective of this paper is to analyze the temporal and spatial variability of the total ozone column (TOC) distributions and trends over Iraq, during the last 30 years (1979–2012) using remote sensing-derived TOC data. Due to shortage of ground-based TOC measurements. TOC data derived from the Total Ozone Mapping Spectrometer (TOMS) for the period 1979–2004 and Ozone Monitoring Instrument (OMI) for the period 2005–2012 with spatial resolution (1o×1o) were used in present study. The spatial, long-term, monthly variations of TOC over Iraq were analysed. For the spatial variability, the latitudinal variability has a large range between (45 to 55) DU in winter and spring whereas during summer and autumn months ranged between (6 to 10) DU. Also represents an annual cycle with maximum in March and minimum in October. In contrast, the longitudinal variability is not significant. The long-term variability represented a notable decline for the period 1979–2012. The ozone negative trend was observed significantly during 1979–2004, for all months with trend ranged between (− 0.3 to 2) DU/year whereas the ozone positive trend was appear clearly during 2005–2007, for all months (0.1 to 2.3) DU/year ,except February and September which presented negative trends. The results can provide comprehensive descriptions of the TOC variations in Iraq and benefit climate change research in this region.

Temporal and Spatial Variability and Trend Investigation of Total Ozone Column over Iraq Employing Remote Sensing Data: 1979-2012

The objective of this paper is to analyze the temporal and spatial variability of the total ozone column (TOC) distributions and trends over Iraq, during the last 30 years (1979–2012) using remote sensing-derived TOC data. Due to shortage of ground-based TOC measurements. TOC data derived from the Total Ozone Mapping Spectrometer (TOMS) for the period 1979–2004 and Ozone Monitoring Instrument (OMI) for the period 2005–2012 with spatial resolution (1o×1o) were used in present study. The spatial, long-term, monthly variations of TOC over Iraq were analysed. For the spatial variability, the latitudinal variability has a large range between (45 to 55) DU in winter and spring whereas during summer and autumn months ranged between (6 to 10) DU. Also represents an annual cycle with maximum in March and minimum in October. In contrast, the longitudinal variability is not significant. The long-term variability represented a notable decline for the period 1979–2012. The ozone negative trend was observed significantly during 1979–2004, for all months with trend ranged between (− 0.3 to 2) DU/year whereas the ozone positive trend was appear clearly during 2005–2007, for all months (0.1 to 2.3) DU/year ,except February and September which presented negative trends. The results can provide comprehensive descriptions of the TOC variations in Iraq and benefit climate change research in this region.

Chemical Composition of PM2.5 Based on Two-Year Measurements at an Urban Site in Beijing

In this study, the daily PM2.5 atmospheric aerosols were collected on quartz and PTFE filters simultaneously from January 2008 to December 2009. Organic carbon (OC) and elemental carbon (EC), water-soluble ions including SO42–, NO3–, Cl–, NH4+, K+, Ca2+, and Mg2+ were analyzed for the samples. The annual average mass concentration of PM2.5 for PTFE was 79 µg m–3. The OC, SO42–, NO3–, NH4+ accounted for about 75 % of PM2.5, and secondary organic carbon (SOC) was estimated about 50% of OC. Monthly averages of SO42–, NO3–, NH4+, K+ were maximum in June and minimum in October, but EC, Cl– displayed the highest in December and the lowest in July, which is related to the coal-combustion emission from heating. Three groups with high, medium and low PM2.5 concentrations were categorized. SO42–, NO3–, OC and NH4+ accounted for 24%, 20%, 21% and 11% of sum of defined components in the high concentration days. In the medium and low concentrations, OC occupied large fractions of defined components. Mass closure was obtained for PTFE, but not for quartz. The PM2.5 mass concentrations on quartz filters were about 50 µg m–3 higher than that on PTFE. The concentrations of water soluble ions on quartz filters were about 60–70% of that on PTFE filters. About 15–30% of PM2.5 was considered as the contribution of water vapor, the artifact of water vapor on quartz filter should be noted in later research works. PM2.5 displayed neutral during the year of 2008 and appeared acidic at the next year according to the calculation of cations/anion, concentration of hydrogen and acidic purity. Carbonaceous aerosols occupied same fractions in neutral and acidic aerosols. While sulfate and nitrate contributed 32% and 21% to PM2.5 for acidic aerosols, and 22%, 17% of PM2.5 from sulfate and nitrate for neutral aerosols.

Investigating the Temporal and Spatial Variability of Total Ozone Column in the Yangtze River Delta Using Satellite Data: 1978–2013

The objective of this work is to analyze the temporal and spatial variability of the total ozone column (TOC) trends over the Yangtze River Delta, the most populated region in China, during the last 35 years (1978–2013) using remote sensing-derived TOC data. Due to the lack of continuous and well-covered ground-based TOC measurements, little is known about the Yangtze River Delta. TOC data derived from the Total Ozone Mapping Spectrometer (TOMS) for the period 1978–2005 and Ozone Monitoring Instrument (OMI) for the period 2004–2013 were used in this study. The spatial, long-term, seasonal, and short-term variations of TOC in this region were analyzed. For the spatial variability, the latitudinal variability has a large range between 3% and 13%, and also represents an annual cycle with maximum in February and minimum in August. In contrast, the longitudinal variability is not significant and just varies between 2% and 4%. The long-term variability represented a notable decline for the period 1978–2013. The ozone depletion was observed significantly during 1978–1999, with linear trend from (−3.2 ± 0.7) DU/decade to (−10.5 ± 0.9) DU/decade. As for seasonal variability, the trend of TOC shows a distinct seasonal pattern, with maximum in April or May and minimum in October or November. The short-term analysis demonstrates the day-to-day changes as well as the six-week system persistence of the TOC. The results can provide comprehensive descriptions of the TOC variations in the Yangtze River Delta and benefit climate change research in this region.

Inverse determination of groundwater inflow using water balance simulations

The IWAS project Ukraine deals among others with the water balance in the headwaters of the river Western Bug. During investigations in the sub-catchment Sasiv, a gap in the water balance was detected by Pluntke et al. (Environ Earth Sci, this issue, 2014). The runoff of this sub-catchment is significantly higher than that of any other catchment in the region. Unexpectedly, in 2011 the runoff was observed to be higher than precipitation. We hypothesize additional subsurface flow in the Sasiv catchment from adjacent aquifers. The hydrological model BROOK90 was used to model water flows. In addition to publicly available meteorological input data from the NOAA and ECA&C databases, own precipitation measurements in Sasiv were used. The mean seasonal leaf area index (LAI)—cycle of forest, grass, and agricultural land was determined using satellite data. To improve the output quality, the model was adapted for the superior catchment Kamianka-Buzka/Western Bug (2,500 km2). It was calibrated for the period 2001–2006 and validated for 2007–2011. Infiltration and drainage parameters were unknown, and were therefore calibrated applying Monte Carlo simulations. It was not possible to calibrate the sub-catchment Sasiv (107 km2) due to high deviations of the natural water balance. Thus, the model was calibrated for the superior catchment and afterwards applied to the Sasiv catchment. The monthly estimated inflow was calculated based on, first, a constant term, which is a fixed monthly inflow with its minimum in October (22 mm) and its maximum in May (41 mm). Secondly, a dynamic term was added. Here, different dependencies were tested, e.g., precipitation, soil moisture, groundwater level, and modelled runoff. The best coefficient of determination was achieved using a monthly modelled runoff from the 4 months before the current time. The model showed a good performance in the validation period (R2 = 0.88). On average, the runoff observed in Sasiv consists of 60 percent groundwater inflow. At the gauge Kamianka-Buzka, this fraction is still about 5 %. The determined LAI cycles and the usage of an additional precipitation station near Sasiv significantly improved the quality of the water balance modelling in the Sasiv sub-catchment. The presented hydrological model approach was extended by hydrogeological simulations to enhance the understanding of processes in groundwater and surface water interactions. Therefore, it was a special challenge to model with scarce data the heterogeneous hydrogeological character of the catchment. The multi-level calibration enables a comprehensible estimation of annual groundwater recharge rates (30–700 mm) of the shallow quaternary aquifer, which is drained by the river Bug system.

한국 태안군 진산리 저서미세조류의 계절별 종조성 및 생물량 변화

Seasonal species composition and biomass of microphytobenthos were examined at the intertidal flats of Jinsanri, Taean, Korea, from April to December 2011. In total, 121 species were identified, including 109 diatoms, 5 blue-green algae, and 5 dinoflagellates. Seasonal variation in species number ranged from 49 to 56 species (minimum in October and maximal in April), while vertical variation across three different shore levels ranged from 64 to 77 species with maximum at high and minimum at low shore. Species diversity ranged from 3.22 to 3.42 seasonally and from 3.50 to 3.17 across vertical shore levels. Seasonal average values of the normalized difference vegetation index and the vegetation index were 0.06 and 1.14, respectively. Chlorophyll a concentrations were <TEX>$66.00-120.73mg/m^2$</TEX>, with a seasonal minimum and maximum in July and October, respectively, and a vertical shore maximum of <TEX>$137.35mg/m^2$</TEX> at mid shore. Phaeopigment concentrations peaked in October (<TEX>$50.78mg/m^2$</TEX>) and at high shore (<TEX>$61.58mg/m^2$</TEX>) and were lowest in December (<TEX>$22.53mg/m^2$</TEX>) and at low shore (<TEX>$15.28mg/m^2$</TEX>). The number of microphytobenthos ranged from 78,556 to 287,898 cells/<TEX>$cm^2$</TEX>, reaching a maximum in April and a minimum in July. The diatoms Paralia sulcata, Navicula sp., and Delphines surirella were dominant at all tidal levels over the study period. Dinoflagellates were dominant in July at low shore, and blue-green algae were abundant between July and October at mid shore. In conclusion, species composition and primary production of microphytobenthos exhibited clear seasonal and vertical patterns.

Seasonal and physiological variation of gross composition of camel milk in&lt;br&gt;Saudi Arabia

Weekly milk samples from ten lactating she camels (Camelus dromedarius) were analyzed regularly for 11 months after parturition. The main values for all samples were 2.54 ± 0.72g/100g fat matter, 3.07 ± 0.30g/100g protein, 4.21 ± 0.37g/100g lactose and 0.76 ± 0.10g/100g ash. Fat content decreased from 3.41% at the first week to 2.29% at 36th week post-partum with rising at the end to 2.95% while protein decreased from 3.44% at week 1 to 2.79% at the end of lactation, and lactose from 4.48% to 3.90%. Ash increased from 0.72% to 0.82% then decreased down to 0.71%. Regarding seasonal variation, maximum level of fat was observed in January (3.46%) and minimum at summer time (2.29% in July). Protein content was maximum in February (3.32%) and minimum in October (2.76%). For lactose, the maximum mean value was 4.38% in February and the minimum in September (3.83%). The ash content was quite variable in January then stable all over the year. All components were highly positively correlated, except between fat and ash content which was not significant. No significant effect of parity, gestation length, calf body weight at birth or adult weight on all milk content. The average total milk production was 1207 L for 11 months range between 875 and 1616 L. The correlation between milk production and milk components are significantly negative.

Structure and seasonal variability of the deep mean circulation of the East Sea (Sea of Japan)

The horizontal structure of deep mean circulation and its seasonal variability in the Japan/East Sea (JES) were studied using profiling float and moored current meter data. The deep circulation in the Japan Basin (JB) flows cyclonically, basically following f/H contours. The correlation between the directions of deep current and f/H contour increases as |▿(f/H)| increases, reaching remarkably high correlation coefficient (>0.8) values in steep slope regions in the JB. In contrast to the JB, the deep mean circulation in the Ulleung/Tsushima Basin (UTB) is generally weak and cyclonic accompanied by sub-basin-scale cyclonic and anticyclonic eddies. The UTB shows a poorer correlation between directions of deep current and f/H contours than other basins. The time-space averaged deep mean current is about 2.8 cm/s and the volume transport in the deep layer (800 m to bottom) in the JB reaches about 10 Sv (10 × 106 m3s−1), which is about four times greater than the inflow transport through the Tsushima Straits. A salient feature is that the amplitude of deep mean current in the JB reveals a remarkable seasonal variation with a maximum in March and minimum in October. The annual range of the seasonal variation is about 30% of the mean velocity, whereas that in the southern JES (UTB and Yamato Basin) is weak.

Horizontal aeolian sediment flux in the Minqin area, a major source of Chinese dust storms

Abstract Minqin has become one of the key dust source areas in China due to its severely degraded eco-environment. However, little is known about how much dust is emitted and transported in this area. Aeolian dust samplers were mounted at 15 heights on a 50 m monitoring tower in Minqin in May 2007 to monitor the horizontal aeolian sediment flux. The monitoring data suggests that the total annual horizontal aeolian sediment flux over Minqin is about 8700 kg m − 1 . Of that annual total, the flux in the PM63, PM20, and PM10 size classes amounted to 1730, 780, and 580 kg m − 1 respectively. The flux in May and June accounted for 64% of the annual total, with a minimum in October. The horizontal aeolian sediment flux, including dust flux, decayed rapidly with increasing height following a modified power function, in agreement with the results of several previous studies. The sediment flux in Minqin depends primarily on the wind's characteristics, especially the maximum wind speeds (which create strong aeolian transport). Precipitation in this arid region had limited significance for reducing aeolian sediment transport. The mean diameter, standard deviation, skewness, and kurtosis of the aeolian sediments varied with height, but varied most significantly within 9 m above the surface. The mean diameter of the aeolian sediment ranged from 20 µm (5.6 o) to 95 µm (3.4 o), and thus primarily represents suspended dust, even though coarse particles of organic and salt aggregates are also present.