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1.
The Liangshui Natural Reserve in Heilongjiang Province of China was selected as the study area.The authors collected the samples of forest litter (Tilia amurensis,Fraxinus mandshurica,Pinus koraiensis,Acer mono,Betula costata,and mixed litter),soil in humus horizon (0-5cm) and soil horizon (5-20cm),and soil macrofauna (Oligochaeta,Geophiloporpha and Juliformia) from 2001 to 2002.The role of soil macrofauna in the material cycle was analyzed through comparing the macro-element contents among various parts of the subsystems and using enrichment index (EI).The results indicate that dynamic changes of various litters are very complicated.The contents of Fe in each kind of litter increase firstly,and then decrease in the study period.The changes of macro-element contents are greater in the broad-leaf litter than in the coniferous litter,and the mixed litter is in the middle level,but the differences among them are not significant.The contents of Mg and Fe in humus are higher than those in soil,but the contents of Ca in soil are higher than that in humus.The dynamic changes of macro-element contents in soil and soil fauna are not consistent with those in litter.The diplopod presented obvious enrichment of Ca and Mg (EI>1),but it does not significantly enrich Fe.Earthworm has a stronger enrichment ability of Fe than diplopod and scolopendra,but EI<1.Soil fauna can make great influences on the material cycle of the subsystems.  相似文献   

2.
The Liangshui Natural Reserve in Heilongjiang Province of China was selected as the study area. The authors collected the samples of forest litter (Tilia amurensis, Fraxinus mandshurica, Pinus koraiensis, Acer mono, Betula costata, and mixed litter), soil in humus horizon (0--5cm) and soil horizon (5-20cm), and soil macrofauna (Oligochaeta, Geophiloporpha and Juliformia) from 2001 to 2002. The role of soil macrofauna in the material cycle was analyzed through comparing the macro-element contents among various parts of the subsystems and using enrichment index (El). The results indicate that dynamic changes of various litters are very complicated. The contents of Fe in each kind of litter increase firstly, and then decrease in the study period. The changes of macro-element contents are greater in the broad-leaf litter than in the coniferous litter, and the mixed litter is in the middle level, but the differences among them are not significant. The contents of Mg and Fe in humus are higher than those in soil, but the contents of Ca in soil are higher than that in humus. The dynamic changes of macro-element contents in soil and soil fauna are not consistent with those in litter. The diplopod presented obvious enrichment of Ca and Mg (E1〉1), but it does not significantly enrich Fe. Earthworm has a stronger enrichment ability of Fe than diplopod and scolopendra, but E1〈1. Soil fauna can make great influences on the material cycle of the subsystems.  相似文献   

3.
In the current study, we determined concentrations and transfer rates of Ag, Al, Ba, Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, Pb, P, Rb, Sr and Zn to Brown Birch Scaber Stalks (Leccinum scabrum) mushrooms emerged in the area of Sudety Mountains (Sudetes) in Poland. Fruiting bodies and topsoil samples beneath L. scabrum were collected form the K odzka Dale. The trace elements were determined using validated method and inductively coupled plasma - atomic emission spectroscopy (ICP-AES) for final measurement. Mushrooms contained Ag, Cr, Hg, Co, Ni and Sr at < 1.0 μg/g dry weight; Ba and Pb at ~1.0 μg/g dw; Cd at < 5 μg/g dw; Cu and Mn at > 10 μg/g dw; Al and Ca at ~100 μg/g dw; Fe, Na, Rb and Zn at 100 to 500 μg/g dw, Mg at ~1,000 μg/g dw; P at ~5,000 μg/g dw and K at ~30,000 μg/g dw. Ca, Mn and Ni were nearly equally distributed between stipes and caps; stipes compared to caps were enriched in Ba, Na and Sr, while caps were enriched in Ag, Al, Cd, Co, Cr, Cu, Fe, K, P, Pb, Rb and Zn. The values of bioconcentration factor (BCF) varied highly depending on chemical element and were >1 for Ag, Cd, Cu, K, Mg, Na, P, Rb and Zn, while <1 for Al, Ba, Ca, Co, Cr, Fe, Mn, Ni, Pb and Sr. Topsoil showed elevated content of lead and mean concentration was 99 ± 32 μg/g dw, while cadmium was at 0.41 ± 0.15 and those two highly toxic to human elements occurred in edible caps of L. scabrum at 4.5 ± 2.2 and 2.9 ± 2.0 μg/g dw, respectively.  相似文献   

4.
A method was developed for content determination of Na, Mg, A1, Si, P,S, C1, K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Ga, Nb, Zr, Y, Sr, Rb, Ba, La and Ce etc. covering 26 major, minor, and trace elements in marine sediment samples using fused glass disc by X-ray Fluorescence spectrometry. Calibration was made using marine sediment certified reference materials and the synthetic standard samples prepared by mixing several marine sediments with stream sediment and carbonate standard samples in different proportions. The matrix effect was corrected using theoretical alpha coefficients, experience coefficients and the scattered radiation as the internal standard (for the trace elements). The accuracy of the method was evaluated by analysis of certified reference materials GBW07314, GBW07334 and GSMS6. The results are in good agreement with the certified values of the standards with RSD less than 2.60%, except for Y, Cr, Ga, Ce, La, Nb, Rb, and V with RSD less than 9.0% (n=12).  相似文献   

5.
本文首次报道海南省产的四种江蓠属中的藻类的十一种微量元素含量与测定方法。  相似文献   

6.
CHANGE OF NUTRIENT IMPORT AND EXPORT IN PROCESS OF RAINFALL IN AILAO MOUNTAIN OF YUNNAN PROVINCEGanJianmin(甘健民);XueJingyi(薛敬意...  相似文献   

7.
Preparation of Fe^2+ chelate of fish protein hydrolysate (Fe-FPH) obtained from low value fish proteins was introduced and its bioactivity was studied by compound enzymolysis. The optimum conditions for hydrolysate chelating Fe^2+ are DH (degree of hydrolysis) at 5%, pH 7.0, 20℃ and 15 min chelating time for FM (material not being defatted). Four types of Fe-FPH including CA (deposit after chelating), CB (deposit in 50% of absolute ethanol solution), CC (suspended deposit in 80% of absolute ethanol solution), and CD (bottom deposit in 80% of absolute ethanol solution) were fractionated with absolute ethanol from FM. Structural analysis through infra-red spectrum revealed that Fe^2+ was combined strongly with amino-group and carboxyl-group in each chelate and each Fe^2+ could form two five-member ring structures. All of the four chelates were shown more significant antioxidative activity and can be used as natural hydrophobic and hydrophilic antioxidant. Among all the chelates, the CB possesses the most effective antioxidative activity at 92% as high as that of a-tocopherol. Among all Fe-FPHs, only CD showed the most effective antibacterial activity against Escherichia coli, Staphylococcus aureus, Salmonella typhi, and Bacillus subtilis and can be used as natural antibacterial. It provides a more effective way for utilization of low value fish proteins and key information of Fe-FPH as additive in food industry.  相似文献   

8.
Apostichopus japonicus is an important invertebrate that is widely used as a tonic food in Asian countries.The purpose of this study is to purify and identify a class of compound,the saponins,from the body wall of A.japonicus,and to establish a new me-thod to determine the quantity of saponins in the sea cucumber.In this study,the saponins of A.japonicus,cladoloside A(CA),were ob-tained from 80%ethanol extract by column chromatography for the first time and were characterized using the spectral method.The resulting purified saponins were then profiled using 1HNMR,13CNMR,and ESI-MS,which revealed the CA molecular formula of C53H82O2 and contained a triterpenoid backbone,a methylglucopyranosyl moiety,a quinovopyranosyl,and two xylopyranosyls.A me-thod for the quantitative determination of CA,comprising microwave-assisted extraction,high-performance liquid chromatography,and diode array detector method,was established.Extraction efficiency was optimized by changing microwave power,extraction sol-vent,volume,time,and temperature.Results showed that under the optimum conditions(extraction time of 10 min,temperature of 45℃,and solvent of 25 mL 70%ethanol under 400 W),the detection limit of CA was 0.0015 mg mL?1,and the recoveries of CA from samples at spiking levels of 10,20,and 50μg g?1 ranged from 90.1%-104%.The proposed method was successfully applied to ana-lyze the saponins in different tissues of A.japonicus collected in different seasons.The method developed in this study can provide quantitative technical support for the quality control of A.japonicus.  相似文献   

9.
The use of a microwave-assisted extraction(MAE) method for the extraction of phlorotannins from Saccharina japonica Aresch(S.japonica) has been evaluated with particular emphasis on the influential parameters,including the ethanol concentration,solid/liquid ratio,extraction time,extraction temperature,and microwave power.The MAE procedure was optimized using single-factor design and orthogonal array design(OAD).The content of total phlorotannins in S.japonica was determined using a Folin-Ciocalteu(FC) assay.A maximum total phlorotannin content of 0.644 mg of phloroglucinol equivalent per gram of dry weight plant(mg PGE/g DW) was obtained using the optimized model,which included an ethanol concentration of 55%,solid/liquid ratio of 1:8,extraction time of 25 min,irradiation power of 400 W,and temperature of 60°C.Under similar conditions,the application of a conventional extraction method led to a lower phlorotannin yield of 0.585 mg PGE/g WD.These results demonstrated that the MAE approach provided better results for the extraction of phlorotannins from S.japonica and was a promising technique for the extraction of phenolic compounds from S.japonica and other materials.In addition,screening tests for the inhibitory activity showed that the phlorotannin-containing extracts significantly inhibited the growth of human hepatocellular carcinoma cells(HepG2) by inducing their apoptosis.The morphological changes that occurred during cell apoptosis were characterized using Hoechst33258 staining.  相似文献   

10.
于1999年元月在海南陵水黎安港采集卡帕藻,应用HPLC、原子吸收等分析手段,系统测定其营养成分(主要包括蛋白质、氨基酸、脂肪、粗纤维、粗灰分、矿物质及微量元素等),并与其它几种大型藻类比较,综合评价卡帕藻的营养价值。结果表明卡帕藻蛋白质含量为6.20%,而粗脂肪和粗灰分较高,分别为2.88%和39.04%;卡帕藻中富含K、Na、Ca、Mg、P、Fe、Zn、Mn、Se等矿物元素,尤其是Se的含量远高于其它几种大型藻类。  相似文献   

11.
Investigations on plant community and micronutrient status of Schirmacher Oasis, East Antarctica have been presented in this paper. The dominant plant communities include moss and lichen. The frequency of species occurrence and changes in species composition at different location varied. Thirty-four soil samples were ana- lyzed for chemical properties of the soils of Schirmacher Oasis and Nunatak, East Antarctica. The most common plant species growing throughout the areas of Sehirmacher Oasis and Nunataks are: Candelariella tiara ( lichen ) and Bryum pseudotriquetrum (moss). Large variations were observed among different soil samples in all the nutri- ents and other measured soil chemical parameters. The soils are characterized by a-cidic pH ranging from 4.42 - 6.80. The mean organic carbon content was 0.62 and ranged from 0. 06 - 1.29%. The electrical conductivity in 1 : 2 soil water ratio ranged from 0.06 - 1.29. The average content of macronutrient cation, which are ammonium acetate extractable was in the order of Ca 〉 K 〉 Na 〉 Mg. The average content of DTPA extractable micronutrient cations was in the order of Fe 〉 Mn 〉 Cu 〉 Zn. Thirty one out of 34 samples contained less than 0.80 ppm DTPA extractable Zn. Correlation studies revealed that content of macronutrient cations significantly and positively correlated to that of chlorides. Electrical conductivity exhibited significant and positive relationship with pH, K, Ca, Mg, Na and chloride content. Sodium (r =0.876 * * ) exhibited highest correlation followed by K (r =0. 831 * * ) with chlo- ride content. The correlation coefficient for chlorides was higher with electrical conductivity (r=0.732* * ) than pH (r =0. 513 * * ). Organic carbon content of the soil was positively correlated with Fe ( r = 0. 442 * ). The nutrient status did not appear to be a limiting factor in growth of plants. Lichen and moss community structure and composition in the study area were not related with fertility status o  相似文献   

12.
We applied solution-based ICP-MS method to quantify the trace-elemental signatures in statoliths of jumbo flying squid, Dosidius gigas, which were collected from the waters off northern and central Chile during the scientific surveys carried out by Chinese squid jigging vessels in 2007 and 2008. The age and spawning date of the squid were back-calculated based on daily increments in statoliths. Eight elemental ratios(Sr/Ca, Ba/Ca, Mg/Ca, Mn/Ca, Na/Ca, Fe/Ca, Cu/Ca and Zn/Ca) were analyzed. It was found that Sr is the second most abundant element next to Ca, followed by Na, Fe, Mg, Zn, Cu, Ba and Mn. There was no significant relationship between element/Ca and sea surface temperature(SST) and sea surface salinity(SSS), although weak negative or positive tendency was found. MANOVA analysis showed that multivariate elemental signatures did not differ among the cohorts spawned in spring, autumn and winter, and no significant difference was found between the northern and central sampling locations. Classification results showed that all individuals of each spawned cohorts were correctly classified. This study demonstrates that the elemental signatures in D. gigas statoliths are potentially a useful tool to improve our understanding of its population structure and habitat environment.  相似文献   

13.
The effects of cadmium(Cd)on metal accumulation,microelements contents,and antioxidant responses in Hexagram-mos otakii were studied.The fish were exposed to 0.2,2.5,or 10μg L?1 Cd for 12 or 24 days.Then,the concentration of Cd and mi-croelements(Ca,Fe,Zn,and Se)were determined in the liver and kidney.Moreover,the activities of antioxidant enzymes including superoxide dismutase(SOD),catalase(CAT),and glutathione-S-transferase(GST),and the content of malondialdehyde(MDA)in the liver and kidney were also measured.A continuous accumulation of Cd was observed throughout the experimental period.Cd accumulation was higher in liver than that in the kidney,while Ca and Fe contents were lower in liver than those in the kidney.Cd exposure resulted in a decrease of Ca and Fe concentrations in the kidney,while there was no effect on the liver.Zn and Se remained unaffected with exposure to Cd.Cd exposure induced severe oxidative stress in H.otakii,as indicated by significant induction of the activities of SOD,CAT,and GST,and a simultaneous increase of MDA content.These data show that antioxidant enzymes and mi-croelements contents can be used as potential biomarkers to monitor environmental health in fish.  相似文献   

14.
Zircon LA-ICP-MS U-Pb age, geochemical and Nd isotopic data are presented for a newly recognized high-Mg dioritic dike from Haicheng, Liaodong Peninsula, NE China, to constrain its petrogenesis. The zircons from the high-Mg diorite exhibit striped absorption and oscillatory growth zoning in the cathodoluminescence (CL) images, and have high Th/U ratios (0. 05-0.9), indicating a magma origin. Zircon LA-ICP-MS U-Pb dating indicates that 206pb/238U ages of 12 spots of zircons are between 167 Ma and 178 Ma, yielding a weighted mean 206pb/238U age of 172 + 2 Ma (MSWD =4. 1 ), which represents the forming age of the high-Mg dioritic dike, i. e. Middle Jurassic. Geochemically, the samples have SiO2 =55.4-60. 6 wt. % , Na20 =2. 2-2.76 wt. % , K20 = 1.32-2. 02 wt. % and (Na2O + K2O) =3.82--4. 47 wt. %, belonging to sub-alkaline series and displaying a calc-alkaline evolutionary trend. They are characterized by high MgO (4. 75-6.85 wt. % ), Mg# (55-61), Cr(130-262 ppm), Ni(63-130 ppm), Sr(568-857 ppm), and Ba(484-1 130 ppm) contents, with geochemical features analogous to those of high-Mg adakites. They show variable end (t) values ( - 1.3 to - 3.9) , with a weighted value of - 2. 7, which plot intermediately between the field of the ancient continental crust and the depleted mantle source, indicating that both the lower crust and mantle source are necessary for the generation of the parent magma of the Haicheng high-Mg diorites. The Haicheng high-Mg dioritic dike in the Liaodong Peninsula and the Jurassic magmatism in the eastern North China Craton formed under a continental crustal thickening setting that may be related to subduction of the Paleo-Pacific oceanic plate.  相似文献   

15.
阿扎鲁岩体分布于哀牢山构造岩浆岩带中,通过野外地质调查与岩体剖面测量、岩石样品采集分析、薄片显微镜下鉴定等手段与方法,对其野外地质特征、岩石学特征及岩石地球化学特征进行了系统研究,并探讨了其形成的构造环境。研究结果表明,阿扎鲁岩体的岩性为花岗岩,岩体分布明显受断裂控制;岩石局部可见后期变质的片岩及糜棱岩,岩石具浅层侵入的特点;阿扎鲁花岗岩的A/NCK多大于1.0,为铝饱和型;具有富硅钾、低钙、贫铁、镁、钛的特点,岩石为高钾钙碱性系列。其主量元素、微量元素及稀土元素地球化学特征均表明,该岩体形成于造山期碰撞后期的弧陆碰撞阶段。   相似文献   

16.
辽宁金伯利岩地质—地球化学研究结果表明,辽宁金伯利岩主元素丰度较世界金伯利岩的平均成分,显示富Ca、Al和贫K、Na、Mg、Si,碱度偏低;与南非、苏联和我国山东含金刚石金伯利岩相比,Fe 质偏高。辽宁金伯利岩含矿程度由富到贫,有 Fe、Mg 组分增高,Ca 质降低,微量元素多趋富集的总体变化趋势。辽南金伯利岩较辽北金伯利岩具有碱性程度相对偏高,V、Li、Rb、Nb、La、Sn、Mo、Cu、Pb、Zn、Ag、Ba、Cd、B、S、F 等元素相对富集,Co、Ni、Cr、Th、Bi、Au、As、Sb、Hg、Sr 等元素相对贫化的特点。二者的元素组合和相关特征有明显差别。辽南金伯利岩 Na、Ca、Mn 3元素的相关组合特征是富、贫(中)金刚石金伯利岩的一个地球化学标志。  相似文献   

17.
In this study, a simple method for the simultaneous determination of trace metals(Cu, V, Co, Zn) in coastal seawater using the Mg(OH)2 coprecipitation inductively coupled plasma mass spectrometry(ICP-MS) was developed. This multi-element method enables the simultaneous extraction of four metals, particularly Co and V. The recoveries of Cu, Co, V and Zn after Mg(OH)2 coprecipitation were 73%, 96%, 94% and 92%, which means that our procedure was well-suited to the determination of these four trace metals. The detection limits were 3.81, 0.18, 6.09 and 1.91 nmol L-1, respectively. Then, applying this method to the simultaneous determination of these four metals in coastal water samples from the East China Sea revealed that the concentrations of Cu, Zn, Co and V were higher in bottom waters compared to water at other depths, and higher concentrations were generally observed at the Yangtze River estuary. Additionally, example vertical profiles of dissolved trace metal concentrations for the East China Sea in spring and autumn are compared. These findings indicate that Zn had the greatest seasonal variation followed by Cu, V and Co. For Zn and Co, the concentrations were higher during spring than during autumn. For Cu and V, the seasonal variation in the concentrations was opposite.  相似文献   

18.
In order to study the element contents and distribution of various mosses collected in the Antarctica, we analyzed the heavy elements of 3 species of Polytri-chum in the Fildes Peninsula, P. alpinum, P. juniperinum and P. alpestre, by synchrotron radiation X-ray fluorescence ( SR-XRF). The result shows that the elements, such as K, Ca, Mn, Fe, Cu, Zn and Sr, are nearly the same in Potytrichum. The peak intensity of K is higher than that of Ca, and the peak intensity of Ca is higher than that of Fe in P. alpinum. In P. juniperinum, the peak intensity of K is higher than that of Ca, and the peak intensity of Ca is close to that of Fe. The peak intensity of K is nearly equal to those of Ca and Fe in P. alpestre. Therefore, the habitats of 3 species of Polytrichum are similar in the Fildes Peninsula. By XRF analyzing of different parts of P. alpestre, we found that the peak intensities of relative concentration of elements are obviously different. The peak intensity of K in apical-bud is the highest in orga  相似文献   

19.
作者利用全省不同地质时代和不同地质构造单元内的页岩41种元素的分析数据,计算出辽宁省全域内的页岩元素丰度休系。同时探讨了元素从中、晚元古代至中生代的演化规律,指出Ca、Cd、Sb、As、Na、Mn、P、Sr的元素丰度随时间序列的演化不断增长,B、F、K、Rb、W、Mg则显示出降低的趋势。某些元素比值从老至新表现出明显的规律性变化,如Sr/Ba、Ca/Mg值的演化具有阶段性,K/Na、Th/U值的演化具有方向性,Al/Ti值的演化则具有周期性。  相似文献   

20.
Characteristics of metals in the aerosols of Zhongshan Station, Antarctica   总被引:1,自引:0,他引:1  
Instrumental neutron activation analysis (INAA) was applied to analyze the bulk, high-volume aerosol samples, collected at Zhongshan Station in the Eastern Antarctica, during 1998-2001, to study the chemical species. .A graphical technique was applied to the INAA data. Results showed that Na, Cl, Mg, Ca, Sr, Br, I, Sr and Rb were marine elements while Al, Sc, Fe and Mn were crustal elements. Compared to marine and crustal elements, five elements (Se、Co、Sb、Zn、Cr) were highly abundant in the aerosols collected at Zhongshan station, which indicated that they might come from the petroleum burning, heating and equipment operation. The presence of pollutant elements suggested that human activities have affected the local environments in Antarctica.  相似文献   

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