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1.
The concentrations of natural radionuclide210Po in various components of the marine organisms of North China coastal waters are described and its contribution to the radiation exposure of marine organisms and man are estimated. Data on its concentrations in different species show that, in general, its concentration in crustaceans and molluses is higher than that in fish, where its concentrations in liver and gut are much higher than that in bone and muscle. An estimation of the dose to marine organisms and man due to exposure to210Po is very necessary for any assessment of the impacts of man-made radionuclides from coastal nuclear power installations.  相似文献   

2.
1-phenylethanol(1-PEA)is a flavor extensively used in the production of co smetics,beverages,and food.The release of 1-PEA into coastal environments has aroused great concern.However,its potential effects on marine organisms are still unknown.In order to provide a better understanding of the ecological risks of 1-PEA in marine environments,this study determined the toxic effects of 1-PEA on two marine diatoms(Phaeodactylum tricornutum and Skeletonema costatum).The diatoms were grown in culture medium containing different concentrations of 1-PEA for 96 h.The contents of chlorophyll a,chlorophyll c,glutathione(GSH),malondialdehyde(MDA),and the activities of superoxide dismutase(SOD),catalase(CAT)and glutathione peroxidase(GPx),were measured at the end of the exposure period.1-PEA was shown to significantly inhibit the growth of diatoms,with 96-h EC_(50) values of 257.14 mg/L and 126.46 mg/L in P.tricornutum and S.costatum,respectively.In P.tricornutum,the levels of SOD,CAT,GPx,GSH,and MDA were stimulated only when 1-PEA concentrations were close to or greater than the 96-h EC_(50)value.However,in S.costatum,the activities of SOD and CAT,and the syntheses of two chlorophylls were inhibited even at an exposure concentration below the 96-h EC_(50) value.Taken together,these findings indicate a potential ecological risk by discharging 1-PEA into coastal areas and its species-specific toxic effects on marine organisms.  相似文献   

3.
China is a large marine country. Developing marine economy is an effective way to solve a series of problems with which man is faced, such as the want of natural resources, space limitation, the environmental deterioration, etc. This article analyzes the rich resources of marine biology, harbor, offshore oil and natural gas and coastal tourism resources in China and describes the developing features and regional differences of marine economy. To realize the sustainable development of marine economy in China, what we need to do are as follows: 1 ) to list exploiting ocean into national development strategy; 2) to realize integrated economy of sea and land; 3) to develop ocean by science and technology; 4) to perfect legal institution of marine environment; 5) to establish new idea of sea defending.  相似文献   

4.
Size-fractionated 210Po and 210Pb, in the size fractions >0.4 μm, >2 μm and >10 μm, were examined to determine the seasonal variability of particulate fluxes in Xiamen Bay. Good correlations between 210Po and particulate organic carbon (POC) or non-Particulate Organic Matter (nPOM) suggested that 210Po can be used to trace the export fluxes of POC and nPOM. Both steady-state (SS) model and nSS model were used to evaluate fluxes of size-fractionated 210Po, results showed that nSS model was better than the SS model in coastal areas. Based on the nSS model, size-fractionated POC fluxes decreased with increasing particle size. For the particle size studied, maximum POC fluxes occurred in autumn, followed by spring, winter, and summer. Fluxes of nPOM were an order of magnitude higher than the corresponding size-fractionated POC fluxes. Differences between size-fractionated nPOM fluxes indicated that hydrodynamic conditions were the main factor regulating transportation of particulate out of the inner Bay. In winter most particulates, including >10 μm particles, were transported under the strongest hydrodynamic conditions. In contrast, only a fraction of the <2 μm particulates were transported from the inner Bay in spring. This study suggested that 210Po is a powerful tracer of seasonal particulate export in coastal seas.  相似文献   

5.
The present paper reports Zn,Cu,Pb,Cd,Ni,Fe,Mn and Co contents in the tissues of oyster,solen,red-tail prawn,sea eel and kelp,taken from Meizhou Bay(and analysed by flame atomicabsorption spectrophotometry after wet digestion)in June 1992,and also the concentration factors esti-mated from the mean metal concentrations in the organisms and water there.Heavy metal concentrationsin every species of the organisms followed the pattern:Fe,Mn,Cu,Zn>Pb,Cd,Ni,Co and in variousorganisms showed considerable variation.In general,levels of most of these metals were in the order:softtissues of the bivalves>the kelp>muscles of the red-tail prawn,the sea eel.The greatest concentrationof most metals was found in the gill or viscera of the sea eel,whereas the muscle tissues,in general,con-tained only low concentrations of them.The Cu,Zn concentration factors of the oyster were higher by1—2 orders of magnitude than that of the other organisms.The observed heavy metal levels were closeto those reported from various waters  相似文献   

6.
Recently, the widespread use of TiO_2 nanoparticles(nano-TiO_2) has attracted the global concern regarding their adverse effects to aquatic organisms. Nanoparticles may get to the aquatic environments and harm the growth of algae. This paper presents the studies of nano-TiO_2 concentrations influence on the photosynthetic characteristics, antioxidant system and antitumor activity of marine macroalgae Gracilaria lemaneiformis after exposed to 0, 5, 10, 20 or 40 mg L-1 of nano-TiO_2. Results showed that the photosynthetic pigment content of G. lemaneiformis obviously decreased and the antioxidant defense system was significantly disturbed after exposure to nano-TiO_2. Compared with control, the maximum level of malondialdehyde showed 3.3-fold increase for 15 days exposure to nano-TiO_2. The activity of superoxide dismutase and catalase enhanced obviously by 1.10-2.24-fold. The aqueous extract of G. lemaneiformis(AEGL) possesses anticancer activity against HepG2 liver cancer cells proliferation and the 48 h-cell inhibition exceeds 35%. But the toxicity of nano-TiO_2 would inhibit the anticancer activity of AEGL. When G. lemaneiformis was exposed to nano-TiO_2, the effect of the aqueous extract of G. lemaneiformis on the cell inhibition, reactive oxygen species production, apoptosis, cycle arrest of HepG2 cells significantly lessened, and which were linearly associated with nano-TiO_2 exposure concentration. Those results further confirmed that nano-TiO_2 can inhibit the anticancer activity of G. lemaneiformis. The results in this work imply that macroalgae can be an effective biomarker of nano-TiO_2 contaminant, and can be useful indicator to evaluate ecological effects of increasing pollutants in marine ecosystem.  相似文献   

7.
掌握澳门附近海域沉积物的污染状况及特征,对于合理安排澳门海洋海岸工程疏浚泥的海洋倾倒,防止造成海洋污染有十分重要的意义。根据1997—1999年连续三年对澳门附近主要区域的海洋沉积物采样测定结果,通过分析认为澳门附近海域沉积物污染具有下列特征:1)沉积物中重金属和油类含量普遍较高,除了总Hg外均高于珠江口海区的其他港口;2)沉积物中污染物的分布受人类活动的影响明显,澳门内港受船只排污、码头作业、陆地工业和生活污水排放的影响,是澳门附近海域沉积物污染最为严重区域;3)受水质交换的影响明显,澳门外港、路环岛东北等区域受珠江径流影响水质交换较快,沉积物中污染物的含量较低,而内港由于水质交换较差,沉积物中污染物的含量相对较高;4)与沉积物的成分组成(吸附)有关,大部分污染物与沉积物中粉砂有较好的相关性,表明粉砂对污染物质有较广泛性的吸附能力,尤其是Cu、Zn、Cd、油类、有机质。  相似文献   

8.
Polychaetes are one of the most important groups of macrobenthic organisms in coastal and marine environments, in terms of diversity and abundance, and play an important role in the functioning of ecosystem. This study aims to describe the structure and spatial distribution of polychaete communities along Essaouira's rocky shoreline(Atlantic coast of Morocco) in relation to the major environmental variables such as granulometry, salinity, temperature, pH, and intertidal range. Twelve sites from these intertidal rocky shores were sampled using a quadrat method during the summer 2016. A total of 4 435 individuals belonging to 34 taxa were recorded. Among the families, Sabellaridae(24%) and Nereididae(23%) were ranked ?rst in terms of abundance of individuals. Sabellaria alveolata(24%) and Perinereis cultrifera(13%) were the dominant species. Diversity( H′) values varied from 2.28 to 3.95. Pielou's index( J′) varied between 0.62 and 0.89. This was essentially due to the low dominance of few species. Cluster analysis was used to characterise Essaouira's rocky shores on the basis of benthic polychaete communities. SIMPER analysis con?rmed the presence of three distinct communities. According to canonical correspondence analysis, the structure and distribution of faunal assemblages of benthic polychaetes was mainly related to topographical complexity, water temperature, hydrodynamic conditions and upwelling. We conclude that these rocky shores show typically high benthic polychaete diversity compared to the taxonomic list of other rocky coasts. In addition, these results constitute a baseline data for the development of a sustainable network for long-term monitoring of benthic polychaete community changes due to ecological factor in?uences and anthropogenic activity impacts.  相似文献   

9.
INTRODUCTIONMarinehedsresultinginenomouslossestousuallyPOpulousandeconondcallyde-veloPedlowandcoastalandestUdrineregi0nsareforngseriousattenti0n.msarticlediscussesP0ssiblepreventivemeasaresagainstInariflehazaIdsbasedonacasestUdyoftheestUedesoftheChanaiiangffiverandQiantanffiver-ThesetwoareasoftheChanaiiangDeltaareboicalofc0astalregionsfreqUenilysufferingfromdrinehazanls,andarethemostsociallyandeconondcallydeveloPedregionsinChina.Theirinhabitantshaveahist0-ryofmorethanathouSandyeare0…  相似文献   

10.
高精度渔业捕捞强度数据是开展捕捞限额管理的前提与关键,也是海洋渔业资源可持续发展的重要保障。因此,本文以挖掘海洋渔业捕捞强度空间特征为出发点,选用2018年2、4、9和11月典型季节的中国籍6364艘渔船1.8亿条高时空粒度AIS数据。运用专家知识经验、空间统计及数据挖掘分析方法,以广西南岸北部湾渔场、广东沿岸和环海南岛周边海域为研究区域,对渔业捕捞强度空间特征展开了细致的挖掘与分析。结果表明：① 广东、广西两省（以下简称“两广”）沿岸海域渔业高强度捕捞主要呈现“团块”向外扩张汇聚成“条带”或“更大团块”的特征,而环海南岛周边主要呈现“团块状”特征;② 受渔业从业人员、渔业作业船舶数量、海洋渔场及海域环境影响,“两广”沿岸近海海域捕捞强度明显高于环海南岛周边海域; ③ 高强度捕捞区域主要集中于近岸30~50 km范围内,且近海捕捞强度高于远海区域,归因于研究区内中小型作业渔船占比较高,达50.9%;④ 渔业捕捞活动受农历传统春节及休渔期等政策因素的影响,春节期间的渔业捕捞强度是所选数据覆盖时间范围中最低的,并且休渔期后（9月）渔业捕捞强度明显高于休渔期前（4月）;⑤ 研究区海岸附近的大型渔港对近岸海域的高强度捕捞具有一定的辐射带动效应。本研究通过对高时空粒度的AIS数据进行处理、分析及深度挖掘,可为近岸海洋渔业捕捞强度探析提供重要数据支撑,服务于海洋渔业可持续发展。  相似文献   

11.
MODIS遥感数据提取赤潮信息方法与应用——以珠江口为例   总被引：2，自引：1，他引：1  
近年来,中国沿海近岸二类水体中的赤潮频发,对海洋环境、社会经济和公众健康都造成较大危害,因此,针对近岸二类水体中较小范围赤潮的遥感监测分析有重要意义。本文的工作主要集中在:(1)分析典型赤潮海水、泥沙浑浊海水、赤潮泥沙混合海水,以及清洁海水的MODIS影像光谱特征;(2)分析叶绿素a法,温度法,荧光法和波段比值法,在近岸小范围赤潮识别应用中的优势和缺点;(3)提出监督分类的赤潮信息提取方法,其中典型赤潮样本的选取基于蓝绿波段反射率比值和MODIS 1,4,3波段。利用本方法,对珠江口海域2006年2月赤潮进行了提取,取得良好的效果。  相似文献   

12.
Intensive use of sulfamethazine(SM_2) in aquaculture has resulted in some detrimental effects to non-targeted organisms. In order to assess its potential ecological risk, it is crucial to have a good understanding on the bioaccumulation and biodegradation of SM_2 in Chlorella pyrenoidosa. The microalgae were treated with 2, 4, and 8 mg L~(-1) of sulfamethazine for 13 days, respectively, showing that the inhibition effects of sulfamethazine on the growth of Chlorella pyrenoidosa increased progressively as the concentrations of sulfamethazine increasing from 2 to 8 mg L~(-1). The peak concentrations of sulfamethazine accumulated in C. pyrenoidosa were 0.225, 0.325, and 0.596 ng per mg FW on day 13 for three treatment groups, respectively, showing a great ability to deplete sulfamethazine from the culture media. On day 13, the percentages of biotic degradation were 48.45%, 60.21% and 69.93%, respectively. The EC_(50) of 10.05 mg L~(-1) was derived which showed no significant risk for C. pyrenoidosa with a calculated risk quotient 1. The activities of superoxide dismutase and catalase increased progressively in response to sulfamethazine and showed a positive correlation to the treatment concentrations. The highest superoxide dismutase activity was achieved at the concentration of 8 mg L~(-1) after 2 d of exposure, which was 1.89 folds higher than that of the control. The activity of catalase has a similar pattern to that of superoxide dismutase with the maximum activity achieved at day 2, which was 3.11 folds higher compared to that of the control. In contrast to superoxide dismutase and catalase, the maximum glutathione S-transferase activity was observed at day 6, showing 2.2 folds higher than that of the control.  相似文献   

13.
大连金州地区震旦纪、早寒武世地层发育。本区该套地层可划分为震旦纪辽南超层序和早寒武世满家滩超层序，在其内部又可进一步划分为南关岭层序、棋盘磨层序、陆海层序、葛屯层序、大林子层序和草坨子层序六个层序地层单位。各层序之间均为不整合，其类型包括陆上暴露带、海岸暴露带及海侵面。每个层序仅由海侵体系域和高水位体系域组成。前者为退积地层结构，后者为进积地层，而中间饥饿段却表现为以加积为主，所有变化都与相对海平面及全球海平面变化有关。在此基础上，建立了区域地层格架，指出了本区该时期沉积范围主要在台地之内部（中陆架），局部发育深水陆棚盆地。  相似文献   

14.
The aim of this work is to research the influence of natural climatic changes on the evolution of the coastal zone in modern times and the possible implication of human activities on the configuration of the present coastline.Comparison of data of two very far and different areas , the Po River delta, Adriatic Sea and the Huanghe River delta, Bohai Sea, reveals the planetary diffusion of climatic fluctuations and their effects on coastal evolution .  相似文献   

15.
1Introduction Red tides occur in recorded history,but in recentyears there is a global increase in the number of theseevents due to coastal pollution and other unclear fac-tors.Some kinds of red tides cause mass deaths of cul-tured animals and thus cause heavy economic losses forcoastwise mariculture(Nakanishi et al.,1996;Changet al.,1998;Zhu et al.,1998;Tada et al.,2001).The investigation on red tide control,however,rem-ains insufficient(Burkholder,1998;Edwards and Clark,1999).Although man…  相似文献   

16.
This study focuses on China's coastal area and its marine economic development. Applying the information diffusion method, the study establishes a kernel density function and its decomposition using a marine economic per capita as the index of the model to depict the dynamic evolution law and the internal influential factors of the Chinese marine economy during 1996–2013. The relative development rate was introduced to analyze the spatial differences in the marine economy's development. In this way, space and time dimensions fully characterized the evolution of the Chinese marine economy. Additionally, the influence of growth and inequality in the process of its development can be analyzed. The study shows that the Chinese marine economy as a whole has been growing, and regional marine economic development is relatively coordinated. In addition, the marine economy began to develop even more rapidly after 2004. There are three factors affecting the dynamic evolution of China's marine economy: first, the most influential mean effect, followed by, second, the variance effect, and third, the least influential residual effect. The biggest influence on the dynamic evolution of the marine economy is the improvement of the development level of the marine economy in the coastal area. Meanwhile, due to the existence of inequality, provinces at higher development levels are more dispersed. Furthermore, the existence of the residual effect weakens the influence of the mean effect, and the influence on the dynamic evolution of the marine economy continuously increases. In the analysis of the influencing factors of the evolution and spatial difference of marine economic development, the level of opening to the outside world, the level of investment in fixed assets and the industrial structure have a positive role in promoting economic development. However, capital investment in scientific human research has a negative correlation with economic development, and does not pass the significant test. The difference in regional development levels and development speed is also very apparent; namely, the provinces with higher development levels generally displayed faster development speeds while those with lower development levels showed slower development speeds across the four periods analyzed.  相似文献   

17.
Copper oxide nanoparticles (CuO-NPs) are among the most widely used metal oxide nanoparticles, which increases the chance of their being released into the marine environment. As the applications of these particles have increased in recent years, their potential impact on the health of marine biota has also increased. However, the toxicological effects of these NPs in the marine environment are poorly known. In the present study, the DNA damaging potential of CuO-NPs in the marine eastern mussel Mytilus trossulus was evaluated and compared to that of dissolved copper exposures. Genotoxicity was assessed by the single cell gel electrophoresis (comet) assay in mussel gill and digestive gland cells. The results showed that copper in both forms (CuO-NPs and dissolved copper) was accumulated to different extents in mussel tissues. The mussel exposed to the dissolved copper attained higher concentrations of copper in the gills than in the digestive gland. In contrast to these results, it was found that CuO-NPs could induce much higher copper accumulation in the digestive gland than in the gills. A clear and statistically significant increase in DNA damage was found in both tissues of the Cu-exposed group compared to the control mussels. Our results indicated that the CuO-NP exposure produced remarkable effects and increased DNA damage significantly in mussel gill cells only. It should be noted that the digestive gland cells were prone to accumulation following CuO-NPs when compared to the gill cells, while the gill cells were more sensitive to the genotoxic effects of CuO-NPs. These results also suggested the need for a complete risk assessment of engineered particles before its arrival in the consumer market.  相似文献   

18.
This study investigated the cytotoxicity of gemcitabine using the marine ciliate Euplotes vannus as the test organism.The median lethal concentrations(LC_(50) values)were determined using acute toxicity tests within an exposure time of 30 min with 0,6,12,24,and 48 mg mL~(-1) gemcitabine.The median inhibition effect(IC_(50) value)on the growth of the ciliate cells was examined using chronic toxicity tests within 5 days(120 h)after exposure for 30 min with 0,0.7,3.5,7,and 14 mg mL~(-1) gemcitabine.The 30-min LC_(50)value was 10.66~-mg mL ~1.The LC_(50) values decreased with increasing exposure times and well fitted to the toxicity curve equation LC_(50)=10.93+28.4e~(-0.19t)(R~2=0.93;P0.05,t=exposure time).The IC_(50) value for growth rates was 7.05 mg mL~(-1),and the inhibition effect on growth rates well fitted to the model equation r_%=0.8681e~(-0.0782Cgem)(r_%means growth rate with inhibition by gemcitabine,C_(gem) means concentrations of gemcitabine,R~2=0.99 and P0.05).The LC_(50) values of a wide range of gemcitabine concentrations could therefore be predicted for any given exposure time.These results suggest that the clinical dose of gemcitabine(20 mg mL~(-1))was higher than the 30-min LC_(50) value,which was almost the same as the 6-min LC_(50) value(19.88 mg mL~(-1))for E.vannus cells.The results also demonstrate that E.vannus can be used as a robust test organism for bioassays of chemotherapeutic drugs during short exposure periods.  相似文献   

19.
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   

20.
Bacteria of the genus Flammeovirga can digest complex polysaccharides (CPs), but no details have been reported regarding the CP depolymerases of these bacteria. MY04, an agarolytic marine bacterium isolated from coastal sediments, has been identified as a new member of the genus Flammeovirga. The MY04 strain is able to utilize multiple CPs as a sole carbon source and grows well on agarose, mannan, or xylan. This strain produces high concentrations of extracellular proteins (490 mg L-1 ± 18.2 mg L-1 liquid culture) that exhibit efficient and extensive degradation activities on various polysaccharides, especially agarose. These proteins have an activity of 310 U mg-1 ± 9.6 U mg-1 proteins. The extracellular agarase system (EAS) in the crude extracellular enzymes contains at least four agarose depolymerases, which are with molecular masses of approximately 30-70 kDa. The EAS is stable at a wide range of pH values (6.0-11.0), temperatures (0-50℃), and sodium chloride (NaCl) concentrations (0- 0.9 mol L-1). Two major degradation products generated from agarose by the EAS are identified to be neoagarotetraose and neoagarohexaose, suggesting that β-agarases are the major constituents of the MY04 EAS. These results suggest that the Flammeovirga strain MY04 and its polysac-charide-degradation system hold great promise in industrial applications.  相似文献   

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