攀枝花市垃圾渗沥液污染物的季度性变化

利用垃圾渗沥液监测数据,考察污染物的季度性变化,结果表明:CODCr、BOD5和氨氮随季度表现为2个梯队性变化;悬浮物随季度有先下降后上升、第二季度最低、第四季度最高的趋势变化。

Seasonal Changes in Photosynthetic Characteristics of Ammopiptanthus mongolicus

Seasonal changes in the photosynthetic characteristics of Ammopiptantus mongolicus (Maxim. )Chen f. were studied. When the net photosynthetic rate decreased with the elevation of air temperature, thestomatal conductance and stomatal limitation value tended to decline simultaneously, while the interoellularCO2 concentration was increased. According to the two criteria discriminating the stomatal limitation of Photosynthesis suggeSted by Fmrquhar and Sharkey, the seasonal changes in these parameters indicated that the decrease in Pn may not be due to stomatal factor. These studies proved that the relative contents of the large subunit of Rubisco and the photochemical activities correlated with the seasonal changes in the net photosyntheticrate, whieh may show that these two factors contribute primarily to the seasonal changeS in CO2 assimilation.

Effect of Altitude and Latitude on Surface Air Temperature across the Qinghai-Tibet Plateau

The correlation between mean surface air temperature and altitude is analyzed in this paper based on the annual and monthly mean surface air temperature data from 106 weather stations over the period 1961-2003 across the Qinghai-Tibet Plateau. The results show that temperature variations not only depend on altitude but also latitude, and there is a gradual decrease in temperature with the increasing altitude and latitude. The overall trend for the vertical temperature lapse rate for the whole plateau is approximately linear. Three methods, namely multivariate composite analysis, simple correlation and traditional stepwise regression, were applied to analyze these three correlations. The results assessed with the first method are well matched to those with the latter two methods. The apparent mean annual near-surface lapse rate is -4.8 ℃ /km and the latitudinal effect is -0.87 ℃ /°latitude. In summer, the altitude influences the temperature variations more significantly with a July lapse rate of -4.3℃/km and the effect of latitude is only -0.28℃ /°latitude. In winter, the reverse happens. The temperature decrease is mainly due to the increase in latitude. The mean January lapse rate is -5.0℃/km, while the effect of latitude is -1.51℃ /°latitude. Comparative analysis for pairs of adjacent stations shows that at a small spatial scale the difference in altitude is the dominant factor affecting differences in mean annual near-surface air temperature, aided to some extent bydifferences of latitude. In contrast, the lapse rate in a small area is greater than the overall mean value for the Qinghai-Tibet Plateau （5 to 13℃ /km）. An increasing trend has been detected for the surface lapse rate with increases in altitude. The temperature difference has obvious seasonal variations, and the trends for the southern group of stations （south of 33 o latitude） and for the more northerly group are opposite, mainly because of the differences in seasonal variation at low altitudes. For yearly changes, the temperature for high-altitude stations occurs earlier clearly. Temperature datasets at high altitude stations are well-correlated, and those in Nanjing were lagged for 1 year but less for contemporaneous correlations. The slope of linear trendline of temperature change for available years is clearly related to altitude, and the amplitude of temperature variation is enlarged by high altitude. The change effect in near-surface lapse rate at the varying altitude is approximately 1.0℃ /km on the rate of warming over a hundred-year period.

Identifying Global Monsoon Troughs and Global Atmospheric Centers of Action on a Pentad Scale

Using two datasets of global pentad grid precipitation and global 850 hPa geopotential height during 1979-2007,this study identified global monsoon troughs and global atmospheric centers of action (ACAs) on a pentad scale.The global monsoon troughs consist of planetary-scale monsoon troughs and peninsula-scale monsoon troughs.Forced by seasonal variations in solar radiation,the inter-tropical convergence zones (ITCZs) represent the planetary-scale monsoon troughs,which are active and shift over the tropical North Pacific,the tropical North Atlantic,and the tropical South Indian oceans.The peninsula-scale monsoon troughs are originated from regional land-sea topography and varied with contrasts in seasonal land-sea surface temperatures and precipitation.During the boreal summer,five peninsula-scale troughs and one planetary-scale trough are distributed in the Asia-Northwest Pacific (NWP) region.In total,22 troughs,nine monsoon troughs,and 19 ACAs in the lower troposphere were identified.Relevant ACAs may be useful in constructing regional monsoon and circulation indices.

Chemical Characteristics and Environmental Significance of Fresh Snow Deposition on Urumqi Glacier No.1 of Tianshan Mountains, China

Ice and snow chemistry of alpine glaciers is crucial for the research of regional atmospheric environment change. Fresh snow samples were weekly collected from Urumqi Glacier No.1 in the Tianshan Mountains, Xin- jiang, China, and the chemical characteristics and seasonal variations of major ions, mineral dust, δ18O and trace metals were measured. Results show that the concentrations of major ions in the snow are Ca2+ > SO42-> NH4+ > NO3-> Cl-> Na+ > Mg2+ > K+, in which Ca2+ is the dominant cation, and SO42-is the dominant anion. All major ions have close positive correlations with each other except NO3-. δ18O shows positive correlation with air temperature change during the study period. Mineral dust particle and major ionic concentrations in fresh snow have obvious seasonal change, with high concentration in spring but low concentration in summer and autumn, which indicates that the chemical mass input from Asian dust activity to snow is very significant. Temporal changes of trace metals in fresh snow, e.g., Cd, Pb, Zn, Al, Fe, have shown that human-induced pollution of central Asian region also has large contribution to the snow chemistry on alpine glaciers of the Tianshan Mountains.

Numerical simulation of wave fi eld in the South China Sea using WAVEWATCH III

Wave fields of the South China Sea （SCS） from 1976 to 2005 were simulated using WAVEWATCH III by inputting high-resolution reanalysis wind field datasets assimilated from several meteorological data sources. Comparisons of wave heights between WAVEWATCH III and TOPEX/Poseidon altimeter and buoy data show a good agreement. Our results show seasonal variation of wave direction as follows： 1. During the summer monsoon （April-September）, waves from south occur from April through September in the southern SCS region, which prevail taking about 40% of the time; 2. During the winter monsoon （December-March）, waves from northeast prevail throughout the SCS for 56% of the period; 3. The dominant wave direction in SCS is NE. The seasonal variation of wave height Hs in SCS shows that in spring, Hs〉l m in the central SCS region and is less than 1 m in other areas. In summer, Hs is higher than in spring. During September- November, influenced by tropical cyclones, Hs is mostly higher than 1 m. East of Hainan Island, Hs〉2 m. In winter, Hs reaches its maximum value influenced by the north-east monsoon, and heights over 2 m are found over a large part of SCS. Finally, we calculated the extreme wave parameters in SCS and found that the extreme wind speed and wave height for the 100-year return period for SCS peaked at 45 m/s and 19 m, respectively, SE of Hainan Island and decreased from north to south.

Seasonal variation of plankton communities influenced by environmental factors in an artificial lake

We evaluated the seasonal variation in plankton community composition in an artificial lake. We conducted microscopic analysis and denaturing gradient gel electrophoresis (DGGE) of PCR-amplified partial 16S rRNAand 18S rRNAgenes to characterize the plankton community. The clustering of unweighted pair group method with arithmetic mean (UPGMA) was then used to investigate the similarity of these plankton communities. DGGE fingerprinting revealed that samples collected at the different sites within a season shared high similarity and were generally grouped together. In contrast, we did not observe any seasonal variation based on microscopic analysis. Redundancy analysis (RDA) of the plankton operational taxonomic units (OTUs) in relation to environmental factors revealed that transparency was negatively correlated with the first axis (R=-0.931), and temperature and total phosphorus (TP) were positively correlated with the first axis (R=0.736 and R=0.660, respectively). In conclusion, plankton communities in the artificial lake exhibited significant seasonal variation. Transparency, phosphorus and temperature appear to be the major factors driving the differences in plankton composition.

Seasonal variability of salinity budget and water exchange in the northern Indian Ocean from HYCOM assimilation

Based on HYbrid Coordinate Ocean Model (HYCOM) assimilation and observations, we analyzed seasonal variability of the salinity budget in the southeastern Arabian Sea (AS) and the southern part of the Bay of Bengal (BOB), as well as water exchange between the two basins. Results show that fresh water flux cannot explain salinity changes in salinity budget of both regions. Oceanic advection decreases salinity in the southeastern AS during the winter monsoon season and increases salinity in the southern BOB during the summer monsoon season. In winter, the Northeast Monsoon Current (NMC) carries fresher water from the BOB westward into the southern AS; this westward advection is confined to 4°-6°N and the upper 180 m south of the Indian peninsula. Part of the less saline water then turns northward, decreasing salinity in the southeastern AS. In summer, the Southwest Monsoon Current (SMC) advects high-salinity water from the AS eastward into the BOB, increasing salinity along its path. This eastward advection of high-salinity water south of the India Peninsula extends southward to 2°N, and the layer becomes shallower than in winter. In addition to the monsoon current, the salinity difference between the two basins is important for salinity advection.

Future projection of East China Sea temperature by dynamic downscaling of the IPCC_AR4 CCSM3 model result

Future temperature distributions of the marginal Chinese seas are studied by dynamic downscaling of global CCSM3 IPCC_AR4 scenario runs. Different forcing fields from 2080-2099 Special Report on Emissions Scenarios （SRES） B1, A1, and A2 to 1980-1999 20C3M are averaged and superimposed on CORE2 and SODA2.2.4 data to force high-resolution regional future simulations using the Regional Ocean Modeling System （ROMS）. Volume transport increments in downscaling simulation support the CCSM3 result that with a weakening subtropical gyre circulation, the Kuroshio Current in the East China Sea （ECS） is possibly strengthened under the global wanning scheme. This mostly relates to local wind change, whereby the summer monsoon is strengthened and winter monsoon weakened. Future temperature fluxes and their seasonal variations are larger than in the CCSM3 result. Downscaling 100 years＇ temperature increments are comparable to the CCSM3, with a minimum in B1 scenario of 1.2-2.0~C and a maximum in A2 scenario of 2.5-4.5~C. More detailed temperature distributions are shown in the downscaling simulation. Larger increments are in the Bohai Sea and middle Yellow Sea, and smaller increments near the southeast coast of China, west coast of Korea, and southern ECS. There is a reduction of advective heat north of Taiwan Island and west of Tsushima in summer, and along the southern part of the Yellow Sea warm current in winter. There is enhancement of advective heat in the northern Yellow Sea in winter, related to the delicate temperature increment distribution. At 50 meter depth, the Yellow Sea cold water mass is destroyed. Our simulations suggest that in the formation season of the cold water mass, regional temperature is higher in the future and the water remains at the bottom until next summer. In summer, the mixed layer is deeper, making it much easier for the strengthened surface heat flux to penetrate to the bottom of this water.

Variability of surface velocity in the Kuroshio Current and adjacent waters derived from Argos drifter buoys and satellite altimeter data

By combining Argos drifter buoys and TOPEX/POSEIDON altimeter data, the time series of sea-surface velocity fields in the Kuroshio Current (KC) and adjacent regions are established. And the variability of the KC from the Luzon Strait to the Tokara Strait is studied based on the velocity fields. The results show that the dominant variability period varies in different segments of the KC: The primary period near the Luzon Strait and to the east of Taiwan Island is the intra-seasonal time scale; the KC on the continental shelf of the ECS is the steadiest segment without obvious periodicity, while the Tokara Strait shows the period of seasonal variability. The diverse periods are caused by the Rossby waves propagating from the interior ocean, with adjustments in topography of island chain and local wind stress.

Seasonal variability of Kuroshio intrusion northeast of Taiwan Island as revealed by self-organizing map

The self-organizing map method is applied to satellite-derived sea-level anomaly fields of1993-2012 to study variations of the Kuroshio intrusion northeast of Taiwan Island.Four major features are revealed,showing significant seasonal variability of the intrusion.In general,the intrusion increases(decreases) with a high(low) sea-level anomaly at the edge of the East China Sea shelf in winter(summer).Open-ocean mesoscale eddies play an additional role in modulating the seasonal variation of the intrusion.Further analyses are needed to study eddy-Kuroshio interaction dynamics.

The Effects of Estuarine Processes on the Fluxes of Inorganic and Organic Carbon in the Yellow River Estuary

Riverine carbon flux is an important component of the global carbon cycle. The spatial and temporal variations of organic and inorganic carbon were examined during both dry and wet seasons in the Yellow River estuary. Concentrations of dissolved organic carbon （DOC） and dissolved inorganic carbon （DIC） in the Yellow River during dry seasons were higher than those during wet seasons. The effective concentrations of DOC （CDOC＊） were higher than the observed DOC at zero salinity. This input of DOC in the Yellow River estuary was due to sediment desorption processes in low salinity regions. In contrast to DOC, the effective concen- trations of DIC were 10% lower than the DIC measured at freshwater end, and the loss of DIC was caused by CaCO3 precipitation in low salinity region, Particulate organic carbon （POC） and particulate inorganic carbon （PIC） contents of the particles stabilized to constant values （0.5%：t：0.05% and 1.8%--0.2%, respectively） within the turbidity maximum zone （TMZ） and showed no noticeable seasonal variations. A rapid drop of PIC and rise of POC occurred simultaneously outside the TMZ due to an intense dilution of riv- erine inorganic-rich particles being transported into a pool of aquatic organic-poor particles outside the TMZ. Annually, the Yellow River transported 6.95× 10^5 t of DIC, 0.64× 10^5 t of DOC, 78.58× 10^5 t of PIC and 2.29× 10^5 t of POC to the sea.

Zooplankton community of Keibul Lamjao National Park (KLNP) Manipur, India in relation to the physico-chemical variables of the water

Keibul Lamjao National Park （KLNP）, a floating park in Loktak Lake, Manipur （India） was studied from Winter （WIN） to Post Monsoon （POM） for its zooplankton composition and some selected water parameters. The resultant data were subjected to multivariate techniques---Principal Component Analysis （PCA） and Canonical Correspondence Analysis （CCA）. Analyses of water parameters with PCA revealed that the first PC axis （PC 1） accounts for maximum variance in the seasonal data, explaining a variability of 91%. The PCA revealed that the seasonal variability in water parameters was due to the wet and dry cycle of seasons and the stations were distinguished on the basis of transparency and turbidity. Zooplankton abundance was dominated by copepods followed by cladocerans. Temporally, abundance of copepods reached a maximum during Post-monsoon （POM） （3 880 ind./L）. Spatially, $6 was found to be most abundant of the other stations in zooplankton. Copepodites and nauplii larvae were the major components of zooplankton. The Rotifera were the least abundant among the three zooplankton groups. Brachionus formed the major component of Rotifera zooplankton at all the stations during the study period. In the Cladocera, Macrothrix was present during all the four seasons, while Pleuroxus, Oxyurella, Kurzia and, Diaphanosoma were rare. The CCA shows that maximal temporal variability in zooplankton abundance was explained by temperature and rainfall. ANOVA revealed no significant difference in mean zooplankton abundance among the seasons, but there was a statistically significant difference among the sites.

Seasonal variation in community structure and body length of dominant copepods around artificial reefs in Xiaoshi Island,China

This study aims to investigate the seasonal variations in copepod community structure and prosome length of dominant species from March 2009 to January 2010 around artificial reefs in Xiaoshi Island, Yellow Sea, Weihai, China. Samples were collected using two types of plankton net （Model I and Model II） for different-sized copepods. The number of taxon was calculated from the data of both the net types, while the copepod abundance was done using the samples from Model II only. Sixteen species of planktonic copepods, including 5 dominant species, were recorded. Results reveal that Oithona similis was the first dominant species from March to June, and was replaced by Paracalanus parvus in September; both dominated the copepod community in January. Acartia hongi was the second dominant species from March to September. Centropages abdominalis was the third dominant species from March to June, and was replaced by O. sirnilis in September and Corycaeus aJfinis in January. C. affinis was the fourth dominant species in September. Population density of the dominant copepods was compared with that of other similar regions. We found that the dominant species were mostly small copepods （〈1 mm） except for adult Centrapages abdominalis. Seasonal variation in prosome length of O. similis, C. abdominalis, and C. affinis, and their copepodites were studied for the first time in China. For P. parvus and A. hongi, seasonal trends in prosome length variation were similar with those in Jiaozhou Bay, Yellow Sea, Qingdao, China, in a similar temperate domain. The results are helpful for future calculation of copepod biomass and production, and for investigation of the relationship between copepods and fish resources.

Changes in Seasonality in China under Enhanced Atmospheric CO_2 Concentration

Seasonality changes in China under elevated atmospheric CO2 concentrations were simulated using nine global climate models, assuming a 1% per year increase in atmospheric CO2. Simulations of 20th century experiments of season changes in China from the periods 1961-80 to 1981-2000 were also assessed using the same models. The results show that the ensemble mean simula- tion of the nine models performs better than that of an individual model simulation. Compared the mean climatology of the last 20 years in the CO2-quadrupling experiments with that in the CO2-doubling ones, the ensemble mean results show that the hottest/coldest continuous-90-day （local summer/winter） mean temperature in- creased by 3.4/4.5℃, 2.7/2.9℃, and 2.9/4.1℃ in Northeast （NE）, Southwest （SW）, and Southeast （SE） China, respectively, indicating a weakening seasonal amplitude （SA）, but by 4.4/4.0℃ in Northwest （NW） China, indicating an enlarging SA. The local summer lengthened by 37/30/66/54 days in NW, NE, SW, and SE China, respec- tively. In some models, the winter disappeared during the CO2-quadrupling period, judging by the threshold based on the CO2-doubling period. The average of the other model simulations show that the local winter shortened by 42/36/61/44 days respectively, in the previously mentioned regions.

Seasonal variability of zonal heat advection in the mixed layer of the tropical Pacific

Zonal heat advection （ZHA） plays an important role in the variability of the thermal structure in the tropical Pacific Ocean, especially in the western Pacific warm pool （WPWP）. Using the Simple Ocean Data Assimilation （SODA） Version 2.02/4 for the period 1958-2007, this paper presents a detailed analysis of the climatological and seasonal ZHA in the tropical Pacific Ocean. Climatologically, ZHA shows a zonal- band spatial pattern associated with equatorial currents and contributes to forming the irregular eastern boundary of the WPWP （EBWP）. Seasonal variation of ZHA with a positive peak from February to July is most prominent in the Nifio3.4 region, where the EBWP is located. The physical mechanism of the seasonal cycle in this region is examined. The mean advection of anomalous temperature, anomalous advection of mean temperature and eddy advection account for 31%, 51%, and 18% of the total seasonal variations, respectively. This suggests that seasonal changes of the South Equatorial Current induced by variability of the trade winds are the dominant contributor to the anomalous advection of mean temperature and hence, the seasonality of ZHA. Heat budget analysis shows that ZHA and surface heat flux make comparable contributions to the seasonal heat variation in the Nifio3.4 region, and that ZHA cools the upper ocean throughout the calendar year except in late boreal spring. The connection between ZHA and EBWP is further explored and a statistical relationship between EBWP, ZHA and surface heat flux is established based on least squares fitting.

Characterization of Stratospheric Aerosol Distributions during the Volcanically Quiescent Period of 1998–2004

The Stratospheric Aerosol and Gas Experiment （SAGE） II aerosol extinction profiles at 1020 nm were used to study the distribution characteristics of stratospheric aerosols during the volcanically quiescent period of 1998-2004. The stratospheric aerosol distributions exhibited hemispheric asymmetry between the Northern Hemisphere （NH） and the Southern Hemisphere （SH）. In the lower stratosphere below 20 km, the zonal averaged aerosol optical depths in the NH were higher than those of the corresponding SH; whereas at higher altitudes above 20 km, the optical depths in the SH-- except the equatorial region--were higher than those of the NH. At 0-10°N and 10-20°N, the stratospheric aerosol optical depth （SAOD） exhibited larger values in boreal winter and lower values in the spring and summer; at 0-10°S and 10-20°S, the SAOD presented small seasonal variations. At 30-40°N, the SAOD presented larger values in the boreal fall and winter and lower values in the spring and summer; while at 30-40°S, the SAOD exhibited larger values in the austral winter and early spring and lower values in the summer and fall. These characteristics can mainly be attributed to the seasonal cycle of the dynamic transport, and the effects of the buildup and breakdown of the polar vortex. At 50-60°S, the SAOD exhibited extremely high values during austral winter associated with the Antarctic polar vortex boundary; at 50-60°N, the SAOD also exhibited larger values during the boreal winter, but it was much less obvious than that of its southern counterpart.

Patella rustica Linnaeus, 1758 （Gastropoda, Patellogastropoda） Inhabiting Coast of Skikda （AIgerie）

The study was undergone on the distribution of abundance of Patella rustica Linnaeus, 1758, with the objective of evaluating of its abundance along the rocky shores of the coast and located sites with high density. A total of twelve sampling sites were selected along the gulf of Skikda. Each station was sampled using quadrats of 25 cm^2. In the present study, two environmental parameters were measured ＂in situ＂ in the water column at each sampling station （water surface temperature, pH）. Biotic communities of the rocky shores are considered to be generally controlled by physical factors such as temperature and desiccation. Therefore, three measurements were made for each abiotic parameter during this survey and mean values were used for statistical analysis. Consequently, the data of abundance （expressed in frequency） of species were calculated based on the distributed individuals along the quadrat. P. rustica is distributed mainly in the East more than in the West particularly from SI to S5. The condition index calculated at 12 stations revealed important seasonal variations, with the maximum during summer season highlighting three stations （S2, S11 and S 12）. This index is also very important in S3 and S4. The factors of pollution at these points had not affected the abundance and index condition.

CONVERSION RATES OF SURFACE HOX RADICALS IN BEIJING CITY

Surface OH radical concentration in Beijing City was measured by impregnated filter trapping technique-high performance liquid chromatography (IFT-HPLC). The observed concentration of OH radical showed obvious diurnal and seasonal variations, with maximum readings at noon or afternoon, similar to 80x10(6)OH/cm(3) in summer and similar to 20x10(6)-40x10(6)OH/cm(3) in fall. On the basis of measured data, the reaction rates related to the photochemical process of HO(x) (OH+HO(2)) were derived and characteristics of atmospheric chemical processes in the city were analyzed. The results showed that conversion rates of atmospheric OH and HO(2) in the summer of Beijing City were about 700x10(6) molecule/(cm(3) . s) and 600x10(6)molecule/(cm(3) . s), respectively. And the net production of OH in the air of the city mainly originated from the photolysis of the gaseous HNO(2), and the main sink of OH were the photochemical reactions with VOCs, NO(2), HCHO and CO. It was different from the clean area.

Typical Surface Seasonal Circulation in the Indian Ocean Derived from Argos Floats

This study investigates the surface circulation in the Indian Ocean using Argos float data over the period 1979-2011.The Argos observations manifest some new phenomena.The climatological annual mean circulation shows that the surface current becomes much stronger after turning around in shore in the western Indian Ocean.In the tropical Indian Ocean,the Great Whirl(GW) to the east of Somalia develops quickly in spring(April-May) as the monsoon reverses to move northward,becoming strongest in summer(June-September) and disappearing in autumn(October-November).The west end of the Agulhas retroflection can reach 18°E,and it exhibits a seasonal variation.At approximately 90°E,the Agulhas Return Current combines with the eastward South Atlantic Current and finally joins the Antarctic Circumpolar Current.