Fatty Acid Composition Analyses of the DCMU Resistant Mutants of Nannochloropsis oculata (Eustigmatophyceae)

1　Introduction　Nannochloropsissp .areoneofpotentialsourcesofpolyunsaturatedfattyacids ,especiallytheeicosapen taentaenoicacid (EPA ,C2 0∶5 ) ,whichisimportantforbothanimalsandhumans .　Thefattyacidcompositionofthisalgaisaffectedbyvariousenvironmentalfactors ,suchaslightintensity(Sukeniketal.,1989;Sukeniketal.,1990 ) ,imply ingthatafactorinfluencingthephotosyntheticprocessmayaffectcellularfattyacidsynthesisandtheirmetabolism .AselectionprogramofincreasingcellularEPAcontenthasbeencarriedo…     

Deep Processes of Basin Evolution:A Case Study of the Southern Songliao Basin and Adjacent Area,NE China in Mesozoic-Cenozoic

1IntroductionOne of the key factors related to basin geody-namics is deep process controlling formation and evolution of sedimentary basin. Depth and tempera-ture of asthenosphere,existence of mantle plume,occurrence of mantle melting,and amounts of melts under depressurization during thinning of lithosphere are controlling factors influenced formation and characteristics of extensional basin directly (Li,1994). Rifting is probably governed by frictional forces exerted on the base of litho…     

Influences of wind on vertical structures of temperature and salinity,and upwelling off Zhejiang coast in summer

In this paper the influences of short-term wind on vertical structures of temperature and salinity, and the upwelling off the Zhejiang coast are studied on the basis of hydrographic data and wind near the coast in Summer (1959–1979). It is pointed out that the variations of vertical distributions of temperature and salinity, and upwelling in this region are closely related to short-term (several days to a week) variation of wind observed. The occurrence of double thermocline, a special oceanographic phenomenon, is partially related to unstable SSW wind field. SSW and NE winds in June are two dynamic factors making intermediate warm water form or disappear. Contribution No. 792 from the Institute of Oceanology, Academia Sinica. This paper was published in Chinese inOceanologia et Limnologia Sinica 14 (1): 14–21, 1983.     

The Hα-cyclonic spectra of a flare loop system on 1981 April 27

The data such as the H-spectrum-spectroheliographic (SSHG) observations, the H-chromospheric observations, etc., of a flare loop prominence which occurred on the western solar limb on 1981 April 27 have been obtained at Yunnan Observatory. The distribution of the internal motions and the macroscopical motion of the flare loop prominence with time and space in the course of its eruption and ascension is derived from the comprehensive analysis of the data. The possible physical pictures and the instability of the motions of the loop are inferred and discussed.     

Correlations between heavy metals and organic carbon extracted by dry oxidation procedure in urban roadside soils

The organic fraction in soils has a significant influence on heavy metal transport. In this study, the organic carbon content was measured by dry oxidation procedure from 21 Xuzhou urban roadside soils to assess the relationships between the concentrations of heavy metals (Pb, Cu, Zn, and Cr) and the amount of organic carbon. The anthropogenic heavy metals (e.g. Pb, Cu, Zn) were strongly correlated with organic carbon (denoted by C_org−c) extracted by dry oxidation while natural heavy metal (e.g. Cr) showed no correlation to the C_org−c. The anthropogenic heavy metals were also strongly correlated with the amount of the total carbon. These results show that the anthropogenic heavy metals are mainly enriched in the organic matter in the Xuzhou urban roadside soils.     

Distribution of Cd,Pb, Zn and Cu and their chemical speciations in soils from a peri-smelter area in northeast China

An exploratory study on soil contamination of heavy metals was carried out surrounding Huludao zinc smelter in Liaoning province, China. The distribution of total heavy metals and their chemical speciations were investigated. The correlations between heavy metal speciations and soil pH values in corresponding sites were also analyzed. In general, Cd, Zn, Pb, Cu and As presented a significant contamination in the area near the smelter, comparied with Environmental Quality Standards for Soils in China. The geoaccumulation index showed the degree of contamination: Cd > Zn > Pb > Cu > As. There was no obvious pollution of Cr and Ni in the studied area. The speciation analysis showed that the dominant fraction of Cd and Zn was the acid soluble fraction, and the second was the residual fraction. Pb was mostly associated with the residual fraction, which constituted more than 50% of total concentration in all samples. Cu in residual fraction accounted for a high percentage (40–80%) of total concentration, and the proportion of Cu in the oxidizable fraction is higher than that of other metals. The distribution pattern of Pb and Zn was obviously affected by soil pH. It seemed that Pb and Zn content in acid solution fraction increased with increasing soil pH values, while Cd content in acid soluble fraction accounted for more proportion in neutral and alkaline groups than acidic one. The fraction distribution patterns of Cu in three pH groups were very similar and independent of soil pH values. And the residual fraction of Cu took a predominant part (50%) of the total content.     

Silicon isotope fractionation in bamboo and its significance to the biogeochemical cycle of silicon

A systematic investigation on silica contents and silicon isotope compositions of bamboos was undertaken. Seven bamboo plants and related soils were collected from seven locations in China. The roots, stem, branch and leaves for each plant were sampled and their silica contents and silicon isotope compositions were determined. The silica contents and silicon isotope compositions of bulk and water-soluble fraction of soils were also measured. The silica contents of studied bamboo organs vary from 0.30% to 9.95%. Within bamboo plant the silica contents show an increasing trend from stem, through branch, to leaves. In bamboo roots the silica is exclusively in the endodermis cells, but in stem, branch and leaves, the silica is accumulated mainly in epidermal cells. The silicon isotope compositions of bamboos exhibit significant variation, from −2.3‰ to 1.8‰, and large and systematic silicon isotope fractionation was observed within each bamboo. The δ³⁰Si values decrease from roots to stem, but then increase from stem, through branch, to leaves. The ranges of δ³⁰Si values within each bamboo vary from 1.0‰ to 3.3‰. Considering the total range of silicon isotope composition in terrestrial samples is only 7‰, the observed silicon isotope variation in single bamboo is significant and remarkable. This kind of silicon isotope variation might be caused by isotope fractionation in a Rayleigh process when SiO₂ precipitated in stem, branches and leaves gradually from plant fluid. In this process the Si isotope fractionation factor between dissolved Si and precipitated Si in bamboo (α_pre-sol) is estimated to be 0.9981. However, other factors should be considered to explain the decrease of δ³⁰Si value from roots to stem, including larger ratio of dissolved H₄SiO₄ to precipitated SiO₂ in roots than in stem. There is a positive correlation between the δ³⁰Si values of water-soluble fractions in soils and those of bulk bamboos, indicating that the dissolved silicon in pore water and phytoliths in soil is the direct sources of silicon taken up by bamboo roots. A biochemical silicon isotope fractionation exists in process of silicon uptake by bamboo roots. Its silicon isotope fractionation factor (α_bam-wa) is estimated to be 0.9988. Considering the distribution patterns of SiO₂ contents and δ³⁰Si values among different bamboo organs, evapotranspiration may be the driving force for an upward flow of a silicon-bearing fluid and silica precipitation. Passive silicon uptake and transportation may be important for bamboo, although the role of active uptake of silicic acid by roots may not be neglected. The samples with relatively high δ³⁰Si values all grew in soils showing high content of organic materials. In contrast, the samples with relatively low δ³⁰Si values all grew in soil showing low content of organic materials. The silicon isotope composition of bamboo may reflect the local soil type and growth conditions. Our study suggests that bamboos may play an important role in global silicon cycle.     

舟山枸杞水域的污损生物生态

本文系１９８８年９月～１９８９年９月在舟山枸杞乌里西岙水域进行挂板试验的结果。共获污损生物１３５种，其中，近岸的油库码头获７７种，远岸的养殖筏获１１０种。动物以亚热带高盐性种类为主，三角藤壶Ｂａｌａｎｕｓｔｒｉｇｕｎｕｓ、小海葵Ａｃｔｉｎｉａ、柯氏分胞孔苔虫Ｃｅｌｌｅｐｏｒｉｎａｃｏｓｔａｚｉｉ、西方三胞苔虫Ｔｒｉｃｅｌａｒｉａｏｃｃｉｄｅｎｔａｌｉｓ、艾氏美熄Ｃｌｔｉａｅｄｗａｒｄｓｉ、广口小桧叶螅Ｓｅｒｔｕｌａｒｅｌｌａｍｉｕｒｒｅｎｓｉｓ等占优势，藻类常见的有长石莼Ｕｌｖａｌｉｎｚａ、肠浒苔Ｅｎｔｅｒｏｍｏｒｐｈｙｉｎｔｅｓｔｉｎａｌｉｓ和日本多管藻Ｐｏｌｙｓｉｐｈｏｎｉａｊａｐｏｎｉｃａ。枸杞污损生物的附着期主要在夏季，附着量也以夏季最大。不同地点附着量的差异极大。夏季由于近岸三角藤壶大量附着，故生物量明显大子远岸，其他季节均是远岸大于近岸。夏季近岸三角藤壶的覆盖面积达１００％，生物量达１８１１９ｇ／ｍ２，占污损生物总生物量的９８％。故夏季是污损生物防除的主要季节，三角藤壶是防除的主要对象。与１９７５～１９７６年嵊山污损生物进行比较，发现两地污损生物的种类组成和群落结构极为相似，说明１０多年以来嵊山     

过渡季节(6—7月)澳大利亚冷高压对赤道辐合带形成的影响

应用车贝雪夫多项式分析过渡季节(6—7月)澳大利亚冷高压与赤道辐合带的关系,得出了对赤道辐合带北移的主要形势以及过程演变特征,最后用合成方法得到它的演变概念模式,为赤道辐合带的北移影响西太平洋及南海地区提供了中期预报的依据。     

珠江口东岸池养鲻鱼的年龄与生长

研究池养条件下鲻鱼ＭｕｇｉｌｃｅｐｈａｌｕｓＬｉｎｎａｅｕｓ的年龄和生长特性，结果表明，鳞片新年轮主要在１０—１月出现；鳞长与体长关系式为：Ｒ—０．００９０７Ｌ（０．７７６４）；Ｉ—Ｖ龄鱼体长和体重相对生长率和生长指标随着年龄增长而逐渐下降；体长与体重关系式为：Ｗ＝１．２７１６×１０（－５）Ｌ（３．０６９５），体长与全长关系式为：ＬＴ＝１０．３７１１＋１．１８０６ＬＢ，当年鱼体长和体重生长与月龄的关系分别为：ＬＢ＝８．６６６９＋２５．５７６９ｔ，Ｗ＝０．１１７０ｔ（３．５５３０），ｖｏｎＢｅｒｔａｌｌａｎｆｆｙ生长参数Ｌ∞＝６１３．２５ｍｍ，Ｋ＝０．３４１２，ｔ０＝－０．８２５，体重生长拐点值为２．４６ａ。