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| 1 | Soil contamination with antibiotics in a typical peri-urban area in eastern China: Seasonal variation, risk assessment, and microbial responses显示文摘The prevalence and persistence of antibiotics in soils has become an emerging environmental issue and an increasing threat to soil security and global public health. The problem is more severe in areas undergoing rapid urbanization; however, the ecological risks of antibiotics,seasonal variability, and associated soil microbial responses in peri-urban soils have not been well-explored. The seasonal soil sampling campaigns were conducted in a typical peri-urban watershed in eastern China to investigate distribution of antibiotics. The results demonstrated higher mean concentrations of most antibiotic compounds in winter than in summer in periurban soils. The seasonal variations of norfloxacin, enrofloxacin, and ciprofloxacin were more significant than those of other antibiotics, due to their higher migration ability and bioavailability.An ecological risk assessment demonstrated that chlortetracycline, ciprofloxacin, doxycycline,and ofloxacin can pose high risks to soil microorganisms. Furthermore, the coexistence of multiple antibiotics obviously poses higher risks than individual compounds. A redundancy analysis demonstrated that tetracyclines mainly showed negative correlations with Firmicutes and Chloroflexi, and quinolones showed obviously negative correlations with Acidobacteria,Gemmatimonadetes, and Nitrospirae, suggesting potential inhibition from antibiotics on biological activities or biodegradation processes. However, the persistence of antibiotics in soil results in a significant decrease in bacterial diversity and a change in dominant species.Our results provide an overview of the seasonal variability of antibiotics and the associated effects on bacterial communities in peri-urban soils. The results can provide scientific guidance on decreasing soil contamination with antibiotics to enhance soil security in similar areas. | Fangkai Zhao Lei Yang Liding Chen Qian Xiang Shoujuan Li Long Sun Xinwei Yu Li Fang | 2019 | Journal of Environmental Sciences2019，31，5： | 19 |
| 2 | PM_(2.5)-bound polycyclic aromatic hydrocarbons(PAHs) in Beijing:Seasonal variations,sources,and risk assessment显示文摘Polycyclic aromatic hydrocarbons(PAHs) have been of health concern due to its carcinogenesis and mutagenesis. In this study, we aimed to assess the variations, sources, and lifetime excessive cancer risk(ECR) attributable to PAHs bound to ambient particulate matters with aerodynamic diameter less than 2.5 μm(PM_(2.5)) in metropolitan Beijing, China. We collected24-hour integrated PM_(2.5) samples on daily basis between November 2014 and June 2015 across both central heating(cold months) and non-heating(warm months) seasons, and further analyzed the PAH components in these daily PM_(2.5) samples. Our results showed that total concentrations of PM_(2.5)-bound PAHs varied between(88.6 ± 75.4) ng/m^3 in the cold months and(11.0 ± 5.9) ng/m^3 in the warm months. Benzo[a]pyrene(Ba P), the carcinogenic marker of PAHs,averaged at 5.7 and 0.4 ng/m^3 in the cold and warm months, respectively. Source apportionment analyses illustrated that gasoline, biomass burning, diesel, coal combustion and cooking were the major contributors, accounting for 12.9%, 17.8%, 24.7%, 24.3% and 6.4% of PM_(2.5)-bound PAHs, respectively. The BaP equivalent lifetime ECR from inhalation of PM_(2.5)-bound PAHs was 16.2 cases per million habitants. Our results suggested that ambient particulate reduction from energy reconstruction and adaption of clean fuels would result in reductions PM_(2.5)-bound PAHs and its associated cancer risks. However, as only particulate phased PAHs was analyzed in the present study, the concentration of ambient PAHs could be underestimated. | Baihuan Feng Lijuan Li Hongbing Xu Tong Wang Rongshan Wu Jie Chen Yi Zhang Shuo Liu Steven Sai Hang Ho Junji Cao Wei Huang | 2019 | Journal of Environmental Sciences2019，31，3： | 17 |
| 3 | Epidemiology of perforated peptic ulcer:Age-and gender-adjusted analysis of incidence and mortality显示文摘AIM:To investigate the epidemiological trends in inci-dence and mortality of perforated peptic ulcer(PPU)in a well-defined Norwegian population. METHODS:A retrospective,population-based,single-center,consecutive cohort study of all patients diag-nosed with benign perforated peptic ulcer.Included were both gastric and duodenal ulcer patients admitted to Stavanger University Hospital between January 2001 and December 2010.Ulcers with a malignant neoplasia diagnosis,verified by histology after biopsy or resection,were excluded.Patients were identified from the hospitals administrative electronic database using pertinent ICD-9 and ICD-10 codes(K25.1,K25.2,K25.5, K25.6,K26.1,K26.2,K26.5,K26.6).Additional searches using appropriate codes for relevant laparoscopic and open surgical procedures(e.g.,JDA 60,JDA 61,JDH 70 and JDH 71)were performed to enable a complete identification of all patients.Patient demographics,presentation patterns and clinical data were retrieved from hospital records and surgical notes.Crude and adjusted incidence and mortality rates were estimated by using national population demographics data. RESULTS:In the study period,a total of 172 patients with PPU were identified.The adjusted incidence rate for the overall 10-year period was 6.5 per 100 000 per year(95%CI:5.6-7.6)and the adjusted mortality rate for the overall 10-year period was 1.1 per 100 000 per year(95%CI:0.7-1.6).A non-significant decline in ad-justed incidence rate from 9.7 to 5.6 occurred during the decade.The standardized mortality ratio for the whole study period was 5.7(95%CI:3.9-8.2),while the total 30-d mortality was 16.3%.No difference in in-cidence or mortality was found between genders.However,for patients≥60 years,the incidence increased over 10-fold,and mortality more than 50-fold,compared to younger ages.The admission rates outside office hours were high with almost two out of three(63%) admissions seen at evening/night time shifts and/or during weekends.The observed seasonal variations in admissions were not statistically significant. CONCLUSION:The adjusted incidence rate,seasonal distribution and mortality rate was stable.PPU fre-quently presents outside regular work-hours.Increase in incidence and mortality occurs with older age. | Kenneth Thorsen Jon Arne Sreide Jan Terje Kvaly Tom Glomsaker Kjetil Sreide | 2013 | World Journal of Gastroenterology2013，19，3： | 14 |
| 4 | Seasonal Variations of Observed Raindrop Size Distribution in East China显示文摘Seasonal variations of rainfall microphysics in East China are investigated using data from the observations of a twodimensional video disdrometer and a vertically pointing micro rain radar. The precipitation and rain drop size distribution(DSD) characteristics are revealed for different rain types and seasons. Summer rainfall is dominated by convective rain,while during the other seasons the contribution of stratiform rain to rainfall amount is equal to or even larger than that of convective rain. The mean mass-weighted diameter versus the generalized intercept parameter pairs of convective rain are plotted roughly around the 'maritime' cluster, indicating a maritime nature of convective precipitation throughout the year in East China. The localized rainfall estimators, i.e., rainfall kinetic energy–rain rate, shape–slope, and radar reflectivity–rain rate relations are further derived. DSD variability is believed to be a major source of diversity of the aforementioned derived estimators. These newly derived relations would certainly improve the accuracy of rainfall kinetic energy estimation, DSD retrieval, and quantitative precipitation estimation in this specific region. | Long WEN Kun ZHAO Mengyao WANG Guifu ZHANG | 2019 | Advances in Atmospheric Sciences2019，36，4： | 14 |
| 5 | Conversion Characteristics between Barotropic and Baroclinic Circulations of the SAH in Its Seasonal Evolution显示文摘In the context of 1958-1997 NCFP NCAR re-analyses, the South Asia high (SAH) was divided into two components, barotropic and haroclinic, the former based on mass weighed vertical integration and the latter on the difference between the measured circulation and the barotropic component counterpart, whereupon the barotropic and baroclinic circulation conversion features were addressed of the research SAH during its seasonal variation. Evidence suggests that i) in summer (winter). the SAH is a thermal (dynamical) system. with dominant baroclinicity (barotropicity). either of the components accounting for approximately 70% of the total contribution; ii) as time progresses from winter to summer, accompanied by the barotropic SAH evolving into its baroclinic analog, the SAH is moving under the' thermal guidance' of its baroclinic component circulation, suggesting that the component circulation precedes the system itself in variation. iii) the reversal happens when it goes from summer to winter, with the SAH displacement under the' dynamic steering' of its barotropic component circulation. | 刘宣飞 朱乾根 郭品文 | 2000 | Advances in Atmospheric Sciences2000，17，1： | 12 |
| 6 | Seasonal vertical crustal mo-tions in China detected by GPS显示文摘By analyzing daily continuous data of Chinese Global Positioning System (GPS) fiducial network with 25 sites from 1999 to 2001, seasonal altitude variations with amplitude of 3-10 mm are detected. Most part of the variations can be explained by the seasonal vertical crustal movements caused by atmospheric pressure variation and mass loading redistribution of non-tidal ocean loading, snow, and soil moisture. Nevertheless, there exists a systematic discrepancy between GPS deduced result and the counterpart predicted by combining various geophysical sources. Much longer time series of GPS site coordinates and further studies are still needed to give out a reasonable interpretation for this discrepancy. | ZHANG Feipeng DONG Danan CHENG Zongyi CHENG Mingkang HUANG Cheng | 2002 | Chinese Science Bulletin2002，47，21： | 11 |
| 7 | ANALYSIS OF SPHERICAL FUNCTION SPECTRAL STRUCTURE OF THE NORTHERN HEMISPHERE 500 HPA MONTHLY MEAN HEIGHT显示文摘Study is undertaken of spherical function spectral structures of long-term mean and anomaly patterns of theNorthern Hemisphere 500 hPa monthly mean geopotential height together with the seasonal and interannual variationsinvestigated.Results show that they are marked by low dimensions and low orders,and the mean and anomaly fields canbe described in terms of 20 and 50 spherical function components,respectively. | 王盘兴 吴洪宝 | 1995 | Acta meteorologica Sinica1995，9，2： | 9 |
| 8 | CO_2 background concentration in the atmosphere over the Chinese mainland显示文摘Based on the long-term monitoring data on CO2 concentration, variation trend and characteristics of CO2 background concentration in the atmosphere over the Chinese mainland are analyzed. Results show that the increasing trend of CO2 background concentration in the atmosphere over the Chinese mainland has appeared during the period of 1991-2000. The average annual CO2 growth increment is 1.59μL/L, and the average annual CO2 growth rate is 0.44%. Distinct seasonal variations of CO2 background concentration are observed, and the averaged amplitude of CO2 seasonal variations is 10.35μL/L. Regional variation characteristics of CO2 background concentration in the atmosphere and possible impact of human activities on these variations over the Chinese mainland are discussed as well. | WANG Gengchen, WEN Yupu, KONG Qinxin, REN Lixin & WANG MulinInstitute of Atmospheric Physics, Chinese Academy of Sciences, Beijing, 100029, China Academy of Meteorological Sciences, China Meteorological Administration, Beijing 100086, China | 2002 | Chinese Science Bulletin2002，47，14： | 9 |
| 9 | Trend,seasonal and diurnal variations of atmospheric CO_2 in Beijing显示文摘The concentration of atmospheric CO2 in Beijing increased rapidly at a mean growth rate of 3.7%·a-1 from 1993 to 1995. After displaying a peak of (409.7±25.9) μmol·mol-1 in 1995, it decreased slowly. Both the almost stable anthropogenic CO2 source and increasing biotic CO2 sink contribute to the drop of CO2 concentration from 1995 to 2000. The seasonal variation of CO2 concentration exhibits a clear cycle with a maximum in winter, averaging (426.8± 20.6)μmol·mol-1, and a minimum in summer, averaging (369.1±6.1)μmol·mol-1. The seasonal variation of CO2 concentration is mainly controlled by phenology. The mean diurnal variation of atmospheric CO2 concentration for a year in Beijing is highly clear: daily maximum CO2 concentration usually occurs at night, but daily minimum CO2 concentration does in the daytime, with a mean diurnal difference more than 34.7μmol·mol-1. It has been revealed that the interannual variations of atmospheric CO2 concentration in winter and autumn regulated the | WANG Yuesi, WANG Changke, GUO Xueqing, LIU Guangren & HUANG YaoLAPC, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100083, China Department of Chemistry, Capital Normal University, Beijing 100037, China | 2002 | Chinese Science Bulletin2002，47，24： | 8 |
| 10 | Variability of the Kuroshio in the East China Sea in 1995显示文摘INTRODUCTIONTherearemanyresearchworksabbottheKUrOShioVTanditSSeaSOnalvacationintheEastChinaho(GUan,1988;Nishizawaetal.,1982;TangandTaShiro,1993;SunandKaneko,1993;Yuanetal.,1990;Yuanetal.,1993;Yuanetal.,1994;Yuanetal.,1995;LiuandYuan,1997a,b).~previou... | Liu Yong gang and Yuan Yao chu (Second Institute of Oceanography, State Oceanic Administration, Hangzhou 310012, China) | 1999 | Acta Oceanologica Sinica1999，18，4： | 6 |
| 11 | Spatial-temporal variation of phytoplankton community structure in Jiaozhou Bay, China显示文摘To better understand the spatial-temporal variation in phytoplankton community structure and its controlling factors in Jiaozhou Bay, Qingdao, North China, four seasonal sampling were carried out in 2017. The phytoplankton community structure and various environmental parameters were examined. The phytoplankton community in the bay was composed of mainly diatoms and dinofl agellates, and several other species of Chrysophyta were also observed. Diatoms were the most dominant phytoplankton group throughout the year, except in spring and winter, when Noctiluca scintillans was co-dominant. High Si/N ratios in summer and fall refl ect the high dominance of diatoms in the two seasons. Temporally, the phytoplankton cell abundance peaked in summer, due mainly to the high temperatures and nutrient concentrations in summer. Spatially, the phytoplankton cell abundance was higher in the northern part of the bay than in the other parts of the bay in four seasons. The diatom cell abundances show signifi cant positive correlations with the nutrient concentrations, while the dinofl agellate cell abundances show no correlation or a negative correlation with the nutrient concentrations but a signifi cant positive correlation with the stratifi cation index. This discrepancy was mainly due to the diff erent survival strategies between diatoms and dinofl agellates. The Shannon-Wiener diversity index ( H′) values in the bay ranged from 0.08 to 4.18, which fell in the range reported in historical studies. The distribution pattern of H′ values was quite diff erent from that of chlorophyll a , indicating that the phytoplankton community structure might have high biomass with a low diversity index. Compared with historical studies, we believe that the dominant phytoplankton species have been changed in recent years due mainly to the changing environment in the Jiaozhou Bay in recent 30 years. | GUO Shujin ZHU Mingliang ZHAO Zengxia LIANG Junhua ZHAO Yongfang DU Juan SUN Xiaoxia | 2019 | Journal of Oceanology and Limnology2019，37，5： | 6 |
| 12 | Seasonal variation in body mass and energy budget in Chinese bulbuls (pycnonotus sinensis)显示文摘Background: Seasonal adjustments in body mass and energy budget are important for the survival of small birds in temperate zones. Seasonal changes in body mass, body temperature, gross energy intake(GEI), digestible energy intake(DEI), body fat content, as well as length and mass of the digestive tract, were measured in Chinese Bulbuls(Pycnonotus sinensis) caught in the wild at Wenzhou, China.Methods: Body mass was determined with a Sartorius balance. The caloric contents of the dried food and feces were then determined using a oxygen bomb calorimeter. Total fat was extracted from the dried carcasses by ether extraction in a Soxhlet apparatus. The digestive tract of each bird was measured and weighed, and was then dried to a constant mass.Results: Body mass showed a significant seasonal variation and was higher in spring and winter than in summer and autumn. Body fat was higher in winter than in other seasons. GEI and DEI were significantly higher in winter.The length and mass of the digestive tract were greatest in winter and the magnitude of both these parameters was positively correlated with body mass, GEI and DEI. Small passerines typically have higher daily energy expenditure in winter, necessitating increased food consumption.Conclusions: This general observation is consistent with the observed winter increase in gut volume and body mass in Chinese Bulbuls. These results suggest that Chinese Bulbuls adjust to winter conditions by increasing their body mass, body fat, GEI, DEI and digestive tract size. | Mengsi Wu Yuchao Xiao Fang Yang Limeng Zhou Weihong Zheng Jinsong Liu | 2014 | Chinese Birds2014，，1： | 6 |
| 13 | The Seasonal Variation of Large Volume Airgun Signals in Hutubi,Xinjiang显示文摘In order to study the seasonal variation of large volume airgun signals in Hutubi,Xinjiang,we analyzed 2,936 signals of airgun source excitations during 2015-2016 received by a seismograph on the bank of the excitation pool.Firstly,the RMS value of the signal amplitude and the daily average temperature were compared after linearly superimposing the signal in days,to analyze the influence of the surface ice cover on the excitation energy release of the airgun source.The result shows that the ice cover will reduce the excitation energy,and the thicker the ice cover is,the more obvious the excitation energy reduces.Secondly,the time-frequency analysis method was used to analyze the influence of the surface ice cover on the signal frequency.It is concluded that the existence of the ice cover has little effect on the signal frequency,but it will affect the intensity of the signal around 4 Hz between 1-2 s after excitation.The cause of these phenomena is that the ice cover affects the bubble oscillation,which in turn affects the energy conversion.The study shows that when using the cross-correlation delay method to calculate the wave velocity,the signals can be divided into two periods according to the daily average temperature:with or without ice cover on the upper surface of the excitation pool.This can help eliminate the influence of the source variation and improve the accuracy of the monitoring results. | SU Jinbo WANG Qiong ZHANG Wenxiu WEI Yunyun CHEN Hao WANG Haitao | 2019 | Earthquake Research in China2019，33，2： | 5 |
| 14 | Seasonal variation of water transport through the Karimata Strait显示文摘Four trawl-resistant bottom mounts, with acoustic Doppler current profilers(ADCPs) embedded, were deployed in the Karimata Strait from November 2008 to June 2015 as part of the South China Sea-Indonesian Seas Transport/Exchange and Impact on Seasonal Fish Migration(SITE) Program, to estimate the volume and property transport between the South China Sea and Indonesian seas via the strait. The observed current data reveal that the volume transport through the Karimata Strait exhibits significant seasonal variation. The winteraveraged(from December to February) transport is –1.99 Sv(1 Sv=1×10~6 m^3/s), while in the boreal summer(from June to August), the average transport is 0.69 Sv. Moreover, the average transport from January 2009 to December2014 is –0.74 Sv(the positive/negative value indicates northward/southward transport). May and September are the transition period. In May, the currents in the Karimata Strait turn northward, consistent with the local monsoon. In September, the southeasterly trade wind is still present over the strait, driving surface water northward, whereas the bottom flow reverses direction, possibly because of the pressure gradient across the strait from north to south. | Yan Wang Tengfei Xu Shujiang Li R.Dwi Susanto Teguh Agustiadi Mukti Trenggono Wei Tan Zexun Wei | 2019 | Acta Oceanologica Sinica2019，38，4： | 5 |
| 15 | BASIC CLIMATOLOGICAL FEATURES OF AIR-SEA HEAT EXCHANGES IN THE SOUTH CHINA SEA (SCS) REGION AND THEIR RELATIONS WITH THE SCS MONSOONS显示文摘By using the NCEP reanalysis data set in 1979-1995, the fluxes of the latent heat, thesensible heat and the net long-wave radiation in the South China Sea (SCS) are expanded by meansof EOF in order to discuss the basic climatological features in the SCS. The detailed analysis showsthat the air-sea heat exchanges in different SCS regions have different seasonal variations. Themiddle and the north of the SCS are the high value regions of the air-sea heat exchanges during thewinter and the summer monsoon periods, respectively, the seasonal variations of air-sea heatexchanges in the south of the SCS are small. In addition, the proportions of different componentsin the total air-sea heat exchanges have different seasonal variations in different regions. Theresults show that the SCS monsoon and the air-sea heat exchanges in the SCS region are theaccompaniments of each other, the great difference of the sensible heat flux between the IndochinaPeninsula and the SCS before the SCS summer monsoon onset may be one of the triggers of thelatter. There maintains a high value center of the sensible heat flux before the 13th dekad, itsdisappearing time consists with that of the summer monsoon onset. It means that as far as the SCSlocal conditions are concerned, the northwest of the Indochina Peninsula is probably a sensitiveregion to the SCS summer monsoon onset and the land may play a leading role in the SCS summermonsoon onset. | 任雪娟 钱永甫 | 1999 | Acta meteorologica Sinica1999，13，4： | 5 |
| 16 | Seasonal variation for the antidiabetic activity of Loranthus micranthus methanol extract显示文摘Objective:To determine the season in which the Eastern Nigeria mistletoe,Loranthus micranthus,parasitic on Persea americana possesses optimum antidiabetic activity and to determine the seasonal variation in the constituents.Methods:The antidiabetic activities of the aqueous methanol extracts of the leaves of Eastern Nigeria mistletoe,Loranthus micranthus, harvested in two seasons of the year,the onset of rainy season(April) and the peak of rainy season(July) were compared.The tests were carried out on six(6) groups(A-F) of alloxaninduced diabetic rats.Groups A and B received 200 mg/kg and 400 mg/kg of the April sample extracts respectively while groups C and D received same doses of the July sample extracts. Group E and F which were the positive and negative controls received 10 mg/kg of glibenclamide and 2 ml/kg of 3%tween 20 respectively.The blood glucose levels of the animals were monitored hourly with a glucometer for six hours.The phytochemical analysis of the plant extracts were also carried out by standard procedures.Results:The results showed that group A and B exhibited significant(P<0.05) percentage reduction in the fasting blood sugar(FBS) level of the animals(38.9%and 39.2%respectively) with maximum reduction observed at the 5th and 6th hour respectively compared to glibenclamide(71.3%).Group C showed no significant (P>0.05) FBS reduction(15.9%) while group D exhibited highly significant(P<0.01) reduction (47.5%) with the maximum reduction occurring after 6 hours.The phytochemical analysis of the crude methanol extracts revealed the presence of carbohydrates,glycosides,saponins, tannins,flavonoids,steroids,terpenoids,acidic compounds,resins and oils.These were present in different proportions in both seasons.Conclusions:This study shows that there is a seasonal, dose-dependent variation in the chemical composition viz-a-viz the antidiabetic activity of the plant under study.This activity is highest at the peak of the rainy season. | Patience Ogoamaka Osadebe Edwin Ogechukwu Omeje Philip Felix Uzor Ernest Kenechukwu David Damian Chiedozie Obiorah | 2010 | Asian Pacific Journal of Tropical Medicine2010，3，3： | 4 |
| 17 | Statistical analysis and model of spread F occurrence in China显示文摘The spread F data obtained over Lanzhou (36.1°N,103.9°E),Chongqing (29.5°N,106.4°E) and Haikou (20.0°N,110.3°E) of China during the period from 1978 to 1997 are used to analyze the occurrence characteristics.The statistical results show that the post midnight spread F occurrence is maximum during the summer solstice months of the lower solar activity period,while post sunset spread F is dominant in equinoxes of higher solar activity period over Haikou station.Over Chongqing and Lanzhou stations,spread F mostly occurs at post midnight and relates negatively with solar activity.Using regression method and Fourier expansion,the preliminary single-station model of spread F occurrence is established and the accuracy of the model is evaluated. | XU Tong1,WU ZhenSen2,HU YanLi1,WU Jian1,SUO YuCheng1 & FENG Jian1 1 National Key Laboratory of Electromagnetic Environment,China Research Institute of Radiowave Propagation,Qingdao 266107,China 2 School of Science,Xidian University,Xi’an 710071,China | 2010 | Science China(Technological Sciences)2010，53，6： | 4 |
| 18 | Temporal–spatial distribution and diastereoisomer pattern of hexabromocyclododecane in the vicinity of a chemical plant显示文摘Hexabromocyclododecane(HBCD) is an effective brominated flame-retardant additive, which is mainly produced in the coastal area of China. This study collected soil samples from a HBCD production plant and its surrounding area in Weifang, Shandong Province, China, and analyzed the temporal–spatial distribution of HBCD and its diastereoisomers in soil. The analysis results showed that the concentration of HBCD in soil near the plant was much higher than normal values, with an annual average concentration reaching 5405 ng/g. Soils 1,2 and 4 km away from the plant were also analyzed, showing that the concentration of HBCD in soil decreased accordingly with the distance from the pollution sources. In order to investigate the effect of the season on HBCD content, the soil samples were collected in all four seasons of the year 2017–2018. According to variations in the wind direction, the concentration of HBCD in soil was also changed. The distribution trend showed that the concentration of HBCD in soil in the downwind direction of the prevailing wind was higher than that in the upwind direction. In addition, this work analyzed the distribution of HBCD in vertical soil sections. It was found that the concentration of HBCD decreased with depth in the soil vertical profile. Finally, the various diastereoisomer patterns in the soil compartments were examined, finding that α-HBCD and γ-HBCD were the predominant diastereoisomers in the soil of the study area. | Xinlei Wang Ruirui Sun Yuedong Chen Xu Zhang Zhaojie Cui | 2019 | Journal of Environmental Sciences2019，31，8： | 4 |
| 19 | Spatial and seasonal distribution of intertidal macrobenthos with their biomass and functional feeding guilds in the Naf River estuary, Bangladesh显示文摘The Naf River estuary is one of the most productive ecological ecosystems in Bangladesh providing an important feeding area for fishes and other aquatic animals.However,detailed information on macrobenthic communities is rarely available in this area.Our study focused on the seasonal and spatial variability of macrobenthic community structure with their biomass and functional guilds.In total,fortyseven taxa were identified under nine major groups and seven functional feeding guilds.Among macrobenthic taxa,Polychaeta was dominant in both seasons and all over the estuary contributing 60%of total benthos.The mean abundance of macrobenthos was higher during the pre-monsoon(2 972±1 994 inds./m^2)than the monsoon(1 572±361 inds./m^2)being maximum at mid-estuary region and minimum at upper and lower estuary regions.Of the diversity indices,density(P=0.01,P=0.003),the number of taxa(P=0.000 3,P=0.000 9)and Margalef′s Index(P=0.000 4,P=0.001)of macrobenthos were significantly different among stations and seasons.Shannon-Weiner index(P=0.009,P=0.12)and Pielou’s evenness index(P=0.03,P=0.14)had significant differences among stations but not among seasons.Cluster analysis suggested that distribution of macrofauna is strongly influenced by seasonality.Among the feeding types,carnivorous were found to be dominant at the upper and mid-estuarine regions,and herbivorous were at lower estuarine regions.Carnivorous species were dominant in both seasons.Omnivores have shown to be the most abundant feeding type in terms of biomass though herbivores were highest during monsoon. | Md. Abu NOMAN MAMUNUR Rashid M SHAHANUL Islam M. Belal HOSSAIN | 2019 | Journal of Oceanology and Limnology2019，37，3： | 3 |
| 20 | Seasonal increase of nest height of the Silver-throated Tit(Aegithalos glaucogularis): can it reduce predation risk?显示文摘Background: Nest predation is usually the main cause of bird nest failure. ‘Predation avoidance hypothesis' of nestsite selection predicts that birds should prefer nest-sites with higher nesting success. We investigated the relationship between nest height and nest fate in Silver-throated Tits(Aegithalos glaucogularis) and asked whether the seasonal change of nest height was adaptive by simultaneously analyzing the seasonal variation of predation rates of the nests.Methods: We monitored nests of the Silver-throated Tit across seven breeding seasons in the Dongzhai National Nature Reserve in Henan Province of China. We compared the difference of nesting success among nests of different heights and analyzed the effect of nesting date on nest height and nest predation rates.Results: The overall nesting success rate was 24.1%(n ds and mammals, followed by snakes(9.11%= 623). Among the failed nests(n). The average height of successf= 472), 59.75% were predated by birul nests was significantly lower than that of predated nests. As the season progresses, the height of the nests increased significantly, companied by the decrease in nesting success. Daily survival rate of the nests also decreased with the progression of the season, regardless of breeding stages.Conclusions: Our findings suggest that nest height is an important factor influencing the nesting success of Silverthroated Tits. However, the seasonal increase of nest height appears inconsistent to the ‘predation avoidance hypothesis', because it is associated with higher predation rates. The reason for this maladaptive behavior remains to be explored in future studies. | Haohui Guan Ye Wen Pengcheng Wang Lei Lv Jiliang Xu Jianqiang Li | 2018 | Avian Research2018，9，4： | 3 |
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