Winter Amounts Research Articles

Seasonal concentration variation and potential influencing factors of organophosphorus flame retardants in a wastewater treatment plant

Organophosphate flame retardants (OPFRs) in both of water and sludge phase of influent and effluent of the STP were investigated in Beijing of China in five seasons. Total OPFRs concentrations in water phase of influent in five seasons were between 600 and 838 ng/L, where total OPFRs concentration was the lowest in summer of 2018. In water phase of influent and effluent, two chlorinated OPFRs (TCEP and TCPP) were major. Alkyl OPFRs decreased the most in water phase from influent to effluent. In sludge phase, the OPFRs amounts in winter were the lowest. The main OPFRs in sludge phase were TEHP and EHDP, which can be explained by the two OPFRs properties (log Kow and log Koc). Higher the values of the log Kow and log Koc of OPFRs, more amounts in sludge phase. The mass flow of OPFRs in influent were analysed by Principal Component Analysis (PCA), indicating that the influent amounts of TCEP, TDCP, TCPP and DCP were main OPFRs in four seasons to influence the characteristics of influent. Compared to OPFRs reduction in some STPs in other countries, alkyl and aryl OPFRs reduction rates were higher than chlorinated OPFRs. TBEP, TEHP and TPHP can always be effectively removed in different seasons and different STPs. The analysis methods of Pearson correlation and linear correlation were processed to check the possible factors affecting OPFRs reduction in STP. OPFRs reduction was related to some STP working parameters. Significant correlation also was found between OPFRs properties and reduction.

Analysis of Arctic Spring Ozone Anomaly in the Phases of QBO and 11-Year Solar Cycle for 1979–2017

Arctic ozone amount in winter to spring shows large year-to-year variation. This study investigates Arctic spring ozone in relation to the phase of quasi-biennial oscillation (QBO)/the 11-year solar cycle, using satellite observations, reanalysis data, and outputs of a chemistry climate model (CCM) during the period of 1979–2017. For this duration, we found that the composite mean of the Northern Hemisphere high-latitude total ozone in the QBO-westerly (QBO-W)/solar minimum (Smin) phase is slightly smaller than those averaged for the QBO-W/Smax and QBO-E/Smax years in March. An analysis of a passive ozone tracer in the CCM simulation indicates that this negative anomaly is primarily caused by transport. The negative anomaly is consistent with a weakening of the residual mean downward motion in the polar lower stratosphere. The contribution of chemical processes estimated using the column amount difference between ozone and the passive ozone tracer is between 10–20% of the total anomaly in March. The lower ozone levels in the Arctic spring during the QBO-W/Smin years are associated with a stronger Arctic polar vortex from late winter to early spring, which is linked to the reduced occurrence of sudden stratospheric warming in the winter during the QBO-W/Smin years.

The Simultaneous Impacts of Seasonal Weather and Solar Conditions on PV Panels Electrical Characteristics

Solar energy usage is thriving day by day. These solar panels are installed to absorb solar energy and produce electrical energy. As a result, the efficiency of solar panels depends on different environmental factors, namely, air temperature, dust (aerosols and accumulated dust), and solar incidence, and photovoltaic panel angles. The effects of real conditions factors on power and efficiency of photovoltaic panels are studied in this paper through testing the panel in real environmental tests. To study the mentioned parameters precisely, two panels with different angles are used. The case study is regarding a region of Tehran, Iran, in summer and winter seasons. The results show that panel efficiency during winter is higher than summer due to air temperature decrement. It is discovered that among air pollutants, Al and Fe have the most share in polluting the air that affect the photovoltaic efficiency. Moreover, measuring the accumulated dust on the panels shows more amount in winter in comparison with summer. The important point in studying the effect of tilt angle is that inconformity between solar incidence and photovoltaic panel angles would result in solar radiation absorption and eventually panel efficiency loss and also, photovoltaic panel installation angle would affect the amount of dust deposited on its surface.

Near-surface Temperature Inversion over the East China Sea

Temperature inversion structure affects the boundary layer activity and convective activity. The frequency, strength, and formation mechanism of near-surface temperature inversion are studied using sounding data at three stations over the East China Sea from 2000 to 2015. The results show that the frequency and strength of the inversion are larger in summer (over Cheju station) than in winter (over ROIG station). The inversion is mainly classified as advection inversion over Cheju station, while mainly classified as radiation inversion over ROIG station. Low cloud amount in winter is larger than that in summer over the East China Sea, which is opposite to the inversion frequency. The reason is that the frequent and strong inversions hinder the height of convection in summer, it is difficult for moist air to reach the lifting condensation level and form clouds.

The Ecosystem Effects of Sand-Binding Shrub Hippophae rhamnoides in Alpine Semi-Arid Desert in the Northeastern Qinghai–Tibet Plateau

The planting of sand-binding vegetation in the Qinghai Lake watershed at the northeastern edge of the Qinghai–Tibet Plateau began in 1980. For this paper, we took the desert on the eastern shore of Qinghai Lake as the study area. We analyzed a variety of aged Hippophae rhamnoides communities and aeolian activities, and we discuss the relationship between them. The main conclusions are as follows: (1) With an increasing number of binding years, the species composition became more abundant, natural vegetation began to recover, and biodiversity increased year by year. At the same time, plant height, canopy width, and community coverage increased, but H. rhamnoides coverage was reduced to 36.70% as coverage of Artemisia desertorum increased to 25.67% after 10 years of fixing. The biomass of H. rhamnoides increased significantly, especially the underground biomass. For example, the biomass of area 15a was about 10 to 30 times that of area 1a. (2) Plants are a useful obstacle to aeolian activity. The presence of plants reduced the wind flow in the upper parts of the plants, but it did not have obvious regular characteristics. The longer the fixation term, the lower the surface sediment transport. It is significant that the sediment transport amount in winter was four times that in the summer. After 15 years of binding, H. rhamnoides grows well, and the community is still stable in the study area.

Arctic cloud annual cycle biases in climate models

Abstract. Arctic clouds exhibit a robust annual cycle with maximum cloudiness in fall and minimum cloudiness in winter. These variations affect energy flows in the Arctic with a large influence on the surface radiative fluxes. Contemporary climate models struggle to reproduce the observed Arctic cloud amount annual cycle and significantly disagree with each other. The goal of this analysis is to quantify the cloud-influencing factors that contribute to winter–summer cloud amount differences, as these seasons are primarily responsible for the model discrepancies with observations. We find that differences in the total cloud amount annual cycle are primarily caused by differences in low, rather than high, clouds; the largest differences occur between the surface and 950 hPa. Grouping models based on their seasonal cycles of cloud amount and stratifying cloud amount by cloud-influencing factors, we find that model groups disagree most under strong lower tropospheric stability, weak to moderate mid-tropospheric subsidence, and cold lower tropospheric air temperatures. Intergroup differences in low cloud amount are found to be a function of lower tropospheric thermodynamic characteristics. Further, we find that models with a larger low cloud amount in winter have a larger ice condensate fraction, whereas models with a larger low cloud amount in summer have a smaller ice condensate fraction. Stratifying model output by the specifics of the cloud microphysical scheme reveals that models treating cloud ice and liquid condensate as separate prognostic variables simulate a larger ice condensate fraction than those that treat total cloud condensate as a prognostic variable and use a temperature-dependent phase partitioning. Thus, the cloud microphysical parameterization is the primary cause of inter-model differences in the Arctic cloud annual cycle, providing further evidence of the important role that cloud ice microphysical processes play in the evolution and modeling of the Arctic climate system.

ПРОДУКТИВНЫЕ И БИОЛОГИЧЕСКИЕ КАЧЕСТВА МОЛОДНЯКА КАЗАХСКОЙ БЕЛОГОЛОВОЙ ПОРОДЫ РАЗНЫХ ГЕНОТИПОВ

The research aim is increasing the potential of meat productivity of young Shagatay Zavodska type of livestock based on a heterogeneous selection of Shagatay cows with bulls – Ural type of hereford. The experience carried out on the breeding farm «Sabit» in West Kazakhstan region according to the scheme: group 1 – bull, group 2 – castrated males, group 3 – heifers of Shagatay breed of Kazakh white cattle and hybrids from crossing Shagatay cows with bulls of Ural Hereford, group 4 – bulls, 5 group – castrated males, 6 group – heifers. Groups were formed on the principle of analogues of 12 animals. Bulls by the age of 15 months of the Ural hereford reached the highest body weight and surpassed shagatai peers taking into account this selection feature in regard to sex by 20.4 kg. In castrates at the age of 18 months, this difference was in favor of the youngsters of group 5 and was 23.0 kg. Heter-ogeneous selection had a positive impact on the important productive qualities by heifers. Youngsters of group 6, born due to servicing bulls of the Ural Hereford, dominated in weight in regard to all analyzed periods. The contents of lizo the meyerhold centre in both winter and summer was greater at animal – hybrids of the Ural hereford and Shagatay animals, winter amount was 0,45-0,94 µg/ml in the summer – from 0.06 to 1.97 µg/ml. Significantly lower bactericidal activity of blood serum and slightly increased amount of lysozyme was shown by hybrids from the Ural hereford in the winter. Regardless of gender, the greatest consumption of both protein (8-41 g) and energy (0.48-2.54 MJ) per unit of body weight gained was characterized by descendants from parents of the Shagatai type of Ka-zakh white-headed breed. Hybrids the offspring of the Ural hereford – used crude protein in feeding more often for the synthesis of dietary protein.

Spatio-temporal variation of throughfall in a hyrcanian plain forest stand in Northern Iran

Abstract Elucidating segregation of precipitation in different components in forest stands is important for proper forest ecosystems management. However, there is a lack of information on important rainfall components viz. throughfall, interception and stemflow in forest watersheds particularly in developing countries. We therefore investigated the spatiotemporal variation of important component of throughfall for a forest stand in a Hyrcanian plain forest in Noor City, northern Iran. The study area contained five species of Quercus castaneifolia, Carpinus betulus, Populus caspica and Parrotia persica. The research was conducted from July 2013 to July 2014 using a systematic sampling method. Ninetysix throughfall collectors were installed in a 3.5 m × 3.5 m grid cells. The canopy covers during the growing/leaf-on (i.e., from May to November) and non-growing/leaf-off (i.e., from December to March) seasons were approximately 41% and 81%, respectively. The mean cumulative throughfall during the study period was 623±31 mm. The average throughfall (TF) as % of rainfall (TFPR) during leaf-on and leaf-off periods were calculated 56±14% and 77±10%, respectively. TF was significantly (R2 = 0.97, p = 0.00006) correlated with gross precipitation. Percent of canopy cover was not correlated with TF except when gross precipitation was <30 mm. A comparison between leaf-off and leaf-on conditions indicated a significantly higher TFPR and corresponding hotspots during leaf-on period. TFPR also differed between seasons with a maximum amount in winter (82%). The results of the study can be effectively used by forest watershed managers for better perception of hydrological behavior of the Hyrcanian forest in the north of Iran under different silvicultural circumstances leading to getting better ecosystem services.

An analysis of daily and monthly precipitation seasonality and regimes in Iran and the associated changes in 1951–2014

Daily and monthly total precipitation of 155 synoptic stations with relatively regular distribution over Iran, covering the 1990–2014 period, were used to investigate the spatial pattern of precipitation seasonality and regimes over Iran, using a set of precipitation seasonality indices. The results suggest a strong agreement between the indices computed at monthly time scale. The result also shows a latitudinal decreasing gradient from the lower index values in the north to the highest values in the south of Iran, suggesting a strong negative relationship between the latitude and the indices. A weak but statistically significant association was also found between the indices and the longitude, showing a gradual west-east contrast between the mountainous western Iran and the central-eastern lowlands and deserts of the country. The spatial patterns of the indices well agree in revealing different precipitation regimes in Iran, in spite of the observed discrepancies in their areal extent of the regions identified. All the indices characterized northern Iran by a precipitation regime having a moderate seasonality, while the mountainous areas of the western and northern Iran are featured by a marked precipitation regime possessing a longer dry season. However, the most seasonal precipitation regime with the longest dry period describes the southern country and some spot areas of the central-eastern Iran. The spatial distribution of the seasonal precipitation regimes and the month and season of maximum precipitation amounts across Iran was also identified, suggesting that from the 24 possible precipitation regimes over the globe, eight were found in Iran, from which a precipitation regime with the highest precipitation amount in winter, followed by autumn, spring, and summer characterized most parts of the country. January and JFM were also found as the month and season of maximum precipitation in a majority of stations distributed over Iran, respectively. The precipitation concentration index (DPCI) computed using daily precipitation data ranges between 0.56 and 0.76 across the country; nonetheless, the values between 0.64 and 0.70 characterized a majority of stations distributed over most parts of Iran. Contrarily to the indices computed at monthly time scale, the DPCI does not show a clear latitudinal pattern over the country. The Mann–Kendal trend test and the Sen slope estimator were applied to the computed indices relative to 16 stations with the longest and complete precipitation records during 1951–2014 time period. The indices time series showed no significant trend in the majority of the stations, indicating that the precipitation regimes of the studied stations did not change over 1951–2014 period.

Simulation on PM2.5 detention service of green space in Haidian District, Beijing, China.

Green space plays an important role in reducing PM2.5, since it can efficiently absorb suspended particles in the air. A quantificational method of dust detention service of green space was proposed in this study, based on the mechanism of PM2.5 reduction by plant. Daily, summer, winter and whole year cumulative dust amounts reduced by green space with different landscape types of Haidian District, Beijing, were quantified. The results showed that both of dust reduction frequency and daily cumulative dust amount in winter were considerably lower than those in summer. Mountain woodlands in the west of Haidian District provided the highest average PM2.5 reduction service, and the fragmented agricultural and forest landscapes in the northern plains provided the highest total dust detention service, while the southern area had the lowest dust detention service except for several parks. PM2.5 detention service model was very useful to quickly quantify how much dust could be reduced by green space and where were these services, which was very important for the development of urban green space and improvement of air quality.

Seasonal changes in the biochemical components of Pseudonereis anomala (Polychaeta, Nereididae) from the Alexandria coast, Egypt

The biochemical composition (carbohydrates, protein, lipids, fatty acids and amino acids) of the nereid polychaete Pseudonereis anomala Gravier 1901, from a shallow part of the Alexandria coast (Egypt), was studied seasonally. The results revealed that P. anomala had a lower water content, higher carbohydrates and protein, but approximately similar or higher lipid levels than several other polychaetes.Fatty acids appeared to be dominated by unsaturated acids, constituting seasonally 49.6–81%, while saturated acids reached high amounts in winter and spring (23.3 and 38.3% respectively). C20:5n-3 was the major polyunsaturated fatty acid, accompanied by small amounts of C18:4n-3, C20:4n-6, C16:1n-7 and C20:1n-9. C18:0 dominated the saturated fatty acids for most of the year, except in autumn when C16:0 was the major one.

Dehydrins associated with the development of frost resistance of Asian white birch

Seasonal changes in the content of dehydrins in Asian white birch (Betula platyphylla Sukacz.) growing under extreme cold conditions of Eastern Siberia (Central Yakutia) were studied for the first time by SDS-PAGE and immunoblotting. Several polypeptides, including putative storage proteins, which content was higher in winter than in other periods, were observed. Intraspecies polymorphism of dehydrins was detected during plant dormancy. The two groups of dehydrins were found: dehydrins with mol wts of 56-73 kD, which were present year-round, and dehydrins with mol wts of 15–21 kD, evidently related to the development of frost resistance because they were absent in summer but present in large amounts in winter. Under low winter temperatures, the highest level of dehydrins coincided with the lowest content of water in buds, which was accompanied by increased plant frost resistance to the highest values.

Interdecadal change in North Korean winter mean rainfall

In the present study, it was found that there was a significant climate regime shift in 1993 from average rainfall amounts in winter (December of a year and January and February of the next year) in North Korea over the last 30 years (1982–2011). This significant climate regime shift in 1993 also appeared in empirical orthogonal function analysis conducted using the winter mean rainfall amounts observed at 26 weather observation stations in North Korea. The reason why winter mean rainfall amounts in North Korea were smaller during the period of 1994–2011 than during the period of 1982–1994 was that anomalous anticyclone was reinforced in regions near Lake Baikal while anomalous cyclone was reinforced on the sea on the east of Japan so that the winter pressure system pattern (west high-east low pattern) appeared and thus anomalous cold and dry northerlies were reinforced in most East Asian regions including North Korea. To figure out the reason why anomalous anticyclone was reinforced further in the East Asian continent in winters during the period of 1994–2011, differences in water equivalent of accumulated snow depths between the two periods were analyzed. As a result, more snow was observed in most East Asian regions during the period of 1994–2011. Therefore, anomalous anticyclone could be further reinforced in the East Asian continent because surface air temperature dropped further due to snow-albedo effect. The surface air temperature cooling deepened further in the East Asian continent during the period of 1994–2011 due to snow-albedo effect was identified through differences in sensible heat net flux between the two periods.

Temporal variation of 7Be fallout and its inventory in purple soil in the Three Gorges Reservoir region, China

The deposition flux of 7Be was measured in the range from 0.4 to 5.2 Bq m−2 d−1, with a mean value of 2.6 Bq m−2 d−1, during the period of May 31, 2009–May 31, 2010 in the Three Gorges Reservoir region, China. The low annual deposition flux of 7Be was probably due to the adsorption of 7Be within high altitude clouds and the Qinling-Daba Mountain’s barrier and blocking effects on the cold air during winter months. There was a seasonal trend for 7Be deposition, showing a spring maximum and winter minimum, which may be attributed to the seasonal folding of tropopause in spring and little rainfall amount in winter. A strong positive correlation (R2 = 0.67) between 7Be deposition flux and rainfall was observed. The depth distribution of 7Be in undisturbed purple soil profiles suggested that the nuclide was mainly distributed within the top 20.0 kg m−2 (~1.5 cm) of soil in depth and the maximum concentration occurred at a depth of 3.0 kg m−2 (~0.2 cm), then the concentration declined quickly and exponentially with depth. The seasonal inventories of 7Be in soils were consistent with the values calculated from the atmospheric fluxes, which shows a great potential for using 7Be as a tracer to assess soil redistribution in purple soil areas of China.

Projected Changes in Flood-Generating Precipitation Extremes Over the Czech Republic in High-Resolution Regional Climate Models

Projected Changes in Flood-Generating Precipitation Extremes Over the Czech Republic in High-Resolution Regional Climate ModelsClimate change scenarios of high quantiles of 5-day precipitation amounts (proxies for flood-generating events) over the Czech Republic are evaluated in an ensemble of high-resolution Regional Climate Model (RCM) simulations from the ENSEMBLES project. The region-of-influence method of the regional frequency analysis is applied as a pooling scheme. This means that for any single gridbox, a homogeneous region (set of gridboxes) is identified and data from that region are used when fitting the Generalized Extreme Value distribution.The climate change scenarios for the late 21st century (2070-2099) show widespread increases in high quantiles of 5-day precipitation amounts in winter, consistent with projected changes in mean winter precipitation. In summer, increases in precipitation extremes occur despite an overall drying (prevailing declines in mean summer precipitation), which may have important hydrological implications. The results for summer suggest a possible substantial change in characteristics of warm-season precipitation over Central Europe, with more severe dry as well as wet extremes. The spatial pattern of projected changes in summer precipitation extremes, with larger increases in the western part of the area and smaller changes towards east, may also point to a declining

Seasonal Variation, Chemical Composition, and Analgesic and Antimicrobial Activities of the Essential Oil from Leaves of Tetradenia riparia (Hochst.) Codd in Southern Brazil

The seasonal variation of the chemical composition of the essential oil from fresh leaves of Tetradenia riparia (Hochst.) Codd grown in southern Brazil was analyzed by GC-MS, and the analgesic and antimicrobial activities of this oil were assayed. The yield of essential oil ranged from 0.17% to 0.26%, with the maximum amount in winter and the minimum in spring. The results obtained from principal components analysis (PCA) revealed the existence of high chemical variability in the different seasons. The samples were clearly discriminated into three groups: winter, autumn, and spring-summer. Samples collected during winter contained the highest percentages of calyculone (24.70%), abietadiene (13.54%), and viridiflorol (4.20%). In autumn, the major constituents were ledol (8.74%) and cis-muurolol-5-en-4-α-ol (13.78%). Samples collected in spring-summer contained the highest percentages of fenchone (12.67%), 14-hydroxy-9-epi-caryophyllene (24.36%), and α-cadinol (8.33%). Oxygenated sesquiterpenes were predominant in all the samples analyzed. The observed chemovariation might be environmentally determined by a seasonal influence. The essential oil, when given orally at a dose of 200 mg/kg, exhibited good analgesic activity on acetic acid-induced writhing in mice, inhibiting the constrictions by 38.94% to 46.13%, and this effect was not affected by seasonal variation. The antimicrobial activity of the essential oil against the bacterial strains: Staphylococcus aureus, Bacillus subtilis, Enterococcus faecalis, Escherichia coli, Salmonella enterica, Pseudomonas aeruginosa, Klebsiella pneumonia, Proteus mirabilis, Morganella morganii, and Enterobacter cloacae, and the pathogenic fungus Candida albicans was assessed by the disc diffusion method and determination of the minimum inhibitory concentration. The results obtained, followed by measurement of the minimum inhibitory concentration (MIC), indicated that S. aureus, B. subtilis, and Candida albicans were the most sensitive microorganisms, showing largest inhibition, and the lowest MIC values varied from 15.6 to 31.2 µg/mL, 7.8 to 15.6 µg/mL, and 31.2 to 62.5 µg/mL, respectively.

Deposition processes of ionic constituents to snow cover

Atmospheric deposition is an important removal process of aerosol particles and gases from the atmosphere. To elucidate the relative contributions of wet and dry processes and in-cloud and below-cloud scavenging based on deposition amounts in winter at Mt. Tateyama, central Japan, we obtained daily samples (December, 2006–March, 2007) of size-segregated aerosol particles and precipitation at Senjyugahara (SJ; 475 m a.s.l.) and vertical samples of spring snow cover at Murododaira (MR, 2450 m a.s.l., 13 km distance from SJ) on the western flank of Mt. Tateyama. The NH 4 + and nssSO 4 2− in aerosols were mostly found in the fine fraction (<2 μm), although Na +, NO 3 −, and nssCa 2+ were mainly detected in the coarse fraction (>2 μm). Average ionic concentrations (μg g −1) in precipitation at SJ were higher about 3.8 for Na + and nssCa 2+, 3.4 for NO 3 −, 3.7 for NH 4 +, 2.5 for nssSO 4 2− than those at MR, whereas cumulative precipitation amounts at SJ and MR were, respectively, 84 and 175 cm of water equivalent. Wet and dry deposition amounts during the study period were estimated for sites using size-segregated aerosol data, winter averages of HNO 3, NH 3, and SO 2 concentrations, and dry deposition velocities. Particle-dry deposition comprised about 3% (Na +) to 11% (NH 4 +) of the total deposition at MR. The maximum amounts of gas dry deposition were estimated, respectively, as 4, 13, and 3% of the total deposition at MR for NH 4 +, NO 3 −, and nssSO 4 2−. The relative contributions of below-cloud scavenging (BCS) between MR and SJ were estimated as considering the wet only deposition amount at MR. Higher contributions of BCS were obtained for Na + (56%) and nssCa 2+ (45%), whereas BCSs for NH 4 +, NO 3 −, and nssSO 4 2− were lower than 28%. Ionic constituents existing predominantly in the coarse fraction showed a large contribution of BCS.

Global warming induced changes in the means and extremities of temperature and precipitation in Hungary

Regional climate changes are still one of the most difficult problems of the climate change issue. Results by three scientific approaches, the raw General Circulation Models (GCM), the mesoscale models, compiled from the PRUDENCE project, and an empirical method, called Natural experiment are compared. The latter approach provides estimations of the future changes based on regression coefficients between the local and global variables in the monotonously warming 1976-2007 period. The global model results comprise results of 9 AOGCMs, whereas in the PRUDENCE set of 5 model outputs are analysed. The listed results start with changes in the seasonal temperature and precipitation averages. Here the signs and the magnitudes are similar according to all approaches: Faster than global mean temperature increases in all seasons, with strongly decreasing precipitation in summer and autumn but increased amounts in winter and spring. There is also a fair agreement of the three approaches in the temperature extremes of the warm half-year in Hungary, with much less unequivocal picture in the frequency of frozen days in the cold half of the year. For precipitation, again, the summer maxima of diurnal totals behave similarly according to the three approaches in all regions of the country. Namely, they exhibit unequivocal increase, whereas no clear picture is seen for frequency of wet/dry days.

Seasonal and Spatial Distribution of Several Endocrine-Disrupting Compounds in the Douro River Estuary, Portugal

Recent studies in the Douro River estuary show signs of pollution in the area and of fish endocrine disruption. However, the chemical nature of the local contamination has not been fully investigated nor have studies checking for the simultaneous presence of endocrine-disrupting chemicals (EDCs), either of animal (estrone, E1; estradiol, E2), pharmaceutical (17alpha-ethynylestradiol, EE2), vegetal (daidzein, DAID; genistein, GEN; biochanin A, BIO-A), or industrial (bisphenol A, BPA; 4-octylphenol, 4-OP; 4-nonylphenol, 4-NP) origins. Thus, the main objective of this study was to examine the presence of these EDCs in estuarine water samples collected, in every season of the year, at nine sampling stations along the estuarine gradient. All samples were processed by two-step solid-phase extraction (Oasis HLB followed by silica) prior to high-performance liquid chromatography with diode-array detection (HPLC-DAD) and gas chromatography-mass spectrometry (GC-MS) analyses. The current data showed that E1 and EE2, all phytoestrogens, and BPA were identified and measured in this estuary. In contrast, 4-OP was only detected by GC-MS and E2 and 4-NP were not found. Additionally, E1 (up to 112.9 ng/L) and EE2 (up to 101.9 ng/L) were both measured in biologically hazardous amounts in winter. In the year sampled, the phytoestrogens suggested a possible seasonal pattern of fluctuation. Both DAID (up to 888.4 ng/L) and GEN (183.6 ng/L) were maximal in early summer, whereas BIO-A (up to 191.4 ng/L) reached its highest concentrations in winter. BPA (up to 10.7 microg/L) also attained highest levels in winter. In December 2005, it is hypothesized that E1, EE2, and BPA concentrations were atypically high due to current drought conditions. Almost all assayed EDCs existed in all seasons and, therefore, might have contributed to endocrine disruption of aquatic animals, previously documented by the high rate of ovotestis in fish caught in this estuary.

Palynological investigations on vegetation and climate change in the Late Quaternary of Lake Rukche area, Gorkha Himal, Central Nepal

Palynological data and pedological investigations including stable isotopes and lignin biomarkers (Glaser et al. in press) from a 4 m core of Lake Rukche (3500 m a.s.l.) enhance our palaeoecological knowledge of the time since the LGM in the Gorkha Himal, Central Nepal. Even before 15000 B.P. forest types became established which prove the existence in Central Nepal of a temperate-humid climate with a considerable amount of winter and spring precipitation from westerly disturbances. Lignin input and pollen data point to a patchy vegetation cover around Lake Rukche with meadow-steppes dominated by Poaceae. Around 15000 B.P. Quercus and Pinus roxburghii dominated the lower altitudes while the vegetation around Lake Rukche was more steppe-like (Chenopodiaceae, Artemisia). Subsequently the climate became warmer and drier as winter and spring precipitation decreased while summer rain remained low. Later on more resource-demanding forests became established under improved temperature and precipitation conditions (Engelhardia). Around Lake Rukche coniferous forests (Abies, Picea) occurred beside meadow-steppes. The transition from the Pleistocene to the Holocene is not recorded. In the Holocene alpine Kobresia-meadows stabilised the soil surface causing sand accumulation to end. During the mid-Holocene (7800–2750 B.P.) humid oak forests with demanding elements (Ilex, Coriaria, Myrsine and Engelhardia) dominated the vegetation cover. A charcoal layer and a marked emergence of fire-induced communities with Pinus roxburghii, Poaceae, Ericaceae and Pteridium are proofs of a first strong anthropogenic change in vegetation which coincided with the climatic deterioration at the onset of the Subatlantic. Since 900 B.P. grazing pressure and the frequency of fires increased, resulting in a replacement of Betula utilis-forests by meadows and woods of Juniperus and Rhododendron. While previous anthropogenic influence increased the biodiversity by promoting replacement communities, recent developments have led to a decrease in biodiversity through loss of natural vegetation communities.