Abundance and characteristics of microplastics in shellfish from Jiaozhou Bay,China     

Kangning ZHANG  Junhua LIANG  Tao LIU  Qingjie LI  Mingliang ZHU  Shan ZHENG  Xiaoxia SUN 《海洋湖沼学报（英文）》2022,(1):163-172

As an emerging pollutant, the presence of microplastics in marine organisms has been concerned increasingly. Shellfish, which are both economically and ecologic...  相似文献   

Effects of different phosphorus concentrations and N/P ratios on the growth and photosynthetic characteristics of <Emphasis Type="Italic">Skeletonema costatum</Emphasis> and <Emphasis Type="Italic">Prorocentrum donghaiense</Emphasis>     

李俊磊  孙晓霞 《中国海洋湖沼学报》2016,34(6):1158-1172

The effects of different phosphorus (P) concentrations (0.36, 3.6, and 36 μmol/L corresponding to low-, middle-, and high-P concentration groups, respectively) and nitrogen (N)/P ratios on the growth and photosynthetic characteristics of Skeletonema costatum and Prorocentrum donghaiense were studied. For both species, the high-P (HP) concentration group showed the greatest algal density and highest specific growth rate. Changes in the maximum efficiency of photosystem II (F _v /F _m ) were monitored under the various P and N/P conditions. The largest decrease in F _v /F _m was in the low-P (LP) group in S. costatum and in the HP group in P. donghaiense. There were high rapid light curves and photochemical quantum yields (Φ _PSII) for S. costatum in the HP group, while the actual photosynthetic capacity was higher in P. donghaiense than in S. costatum in the MP group. Under eutrophic but relatively P-restricted conditions, P. donghaiense had higher photosynthetic activity and potential, which could cause this dinoflagellate to increasingly dominate the phytoplankton community in these conditions. Under the same P concentration and N/P ratio, P. donghaiense had a larger relative maximum rate of electron transport and higher Φ _{PS II} values than those of S. costatum. These differences between P. donghaiense and S. costatum may explain the interaction and succession patterns of these two species in the Changjiang (Yangtze) River estuary from a photosynthesis perspective.  相似文献   

Occurrence modes of silver in the Ni-Mo-PGE polymetallic layer of the Lower Cambrian black shales in Zunyi,Guizhou Province,South China     

Tao Han  Xiaoqing Zhu  Shirong Liu  Xiaoxia Li 《中国地球化学学报》2014,33(4):387-392

The Ni-Mo-PGE polymetallic mineralization of the Lower Cambrian black shales locate in Zunyi, South China and contain abundant noble metals such as Ag, Au and PGE, and especially Ag with average concentration of 64×10-6. The occurrence modes of Ag have been investigated using methods of selective chemical dissolution and transmission electron microscopy. The results demonstrate that the occurrence modes of Ag are complex and diversiform. It might be associated with clay minerals, organic matter, sulfides and also occurred as native silver and sulfides with nanometer in size. Combined with results of previous studies, we suggest that the sulfides, clay minerals and organic matter which hosted in the Ni-Mo-PGE polymetallic ores of black shales can play the roles of important reduction and adsorption geochemical barriers for the enrichment and distribution of silver. This study further implies that the selective chemical dissolution and transmission electron microscopy may pave the way to study the occurrence modes of other noble metals in black shales.  相似文献   

土地利用动态监测的LFF图像融合改进应用   总被引：1，自引：0，他引：1  

吴连喜余水根  刘晓梅苏小霞 《地球信息科学学报》2004,6(3):94-98,2

遥感是快速获取土地利用/土地覆盖现势信息的重要手段之一。由于不同类型的卫星传感器获取同一地区的遥感数据日益增多,对不同平台、不同光谱响应范围的遥感数据源,用常规的遥感图像融合方法如HSI变换法、Brovey变换法和PCA变换法进行融合时,存在不同程度的光谱扭曲现象,即融合后图像的色彩与多光谱图像存在较大差异,从而影响了地物的识别。针对不同平台、不同光谱响应范围的遥感数据,本文在HSI变换的基础上,提出了一种改进的方法,即,首先对高几何分辨率的全色波段进行LoG滤波,然后将LoG滤波后的全色波段与多光谱经HSI正变换后的强度分量,进行灰度直方图匹配,并替换之,经HSI逆变换便得到融合图像。分析结果表明：LFF融合法的光谱保持性能优于HSI变换法,LFF融合后图像的分类精度高于HSI融合后的图像,LFF融合法是一种能较好保持光谱特性的融合方法。  相似文献   

西南印度洋中脊玄武岩地球化学特征及其对岩浆过程的指示意义     

韩宗珠  孙苑高  王传  孙晓霞  刘明  来志庆 《海洋地质前沿》2021,37(1):11-19

对采自西南印度洋中脊(SWIR)50°E附近5个站位的玄武岩样品进行了岩石学和元素地球化学研究。样品主量元素、TAS分类图解和AFM图解显示,SWIR研究区样品类型主要为低钾拉斑玄武岩。相对原始地幔SWIR区玄武岩具有Ba、Nb、Sr负异常,K表现为正异常。稀土元素分配模式均为左倾型,具有轻微的Eu、Ce正异常;SWIR区玄武岩都起源于上地幔,SWIR玄武岩则明显向EMⅡ端元偏移。SWIR玄武岩地幔源区相对最为富集,可能为DM和EMⅡ的混合源区,存在少量的陆壳成分。研究区玄武质岩浆起源深度为尖晶石橄榄岩区域处于中度还原环境下,经历了明显的橄榄石+单斜辉石+斜长石的分离结晶。  相似文献   

Ionic‐Liquid‐Assisted Hydrothermal Synthesis of Ag/AgBr for Photodegradation of Imidacloprid under Visible Light     

Dandan Guo  Xiaoqing Zhu  Sheyun Chen  Cenling Wang  Mingli Pi  Xiaoxia Chen  Yuqing Shi  Jingtao Dai 《洁净——土壤、空气、水》2019,47(5)

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Method for Determining CYP2C9 Activity in Earthworms and its Responses to Benzo[a]pyrene or Pyrene in Soil     

Xiaoxia Yang  Jiuping Gong  Jianrong Kai  Yufang Song  Junjie Lin  Jianfei Liu 《洁净——土壤、空气、水》2019,47(7)

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无人机倾斜摄影技术在地震烈度评估中的应用——以九寨沟7.0级地震为例     

许建华  张雪华  王晓青  杜晓霞  袁小祥 《中国地震》2017,33(4):655-662

以九寨沟7.0级地震为例,通过阐述无人机倾斜摄影技术的相关原理,说明该技术在地震烈度评估中的应用价值。结果表明,使用无人机倾斜摄影技术不仅能够直观地、全方位地展示震害信息,同时,还能对裂缝、滑坡等几何信息进行量测,为烈度评估等提供更加精确的信息。  相似文献   

长江口内外表层沉积物中营养元素的分布特征研究   总被引：8，自引：0，他引：8  

吕晓霞  翟世奎  于增慧  张怀静 《海洋通报》2005,24(2):40-45

通过对长江口内外9个表层沉积物中不同形态碳、氮、磷含量的测定,得到了长江口内外表层沉积物中营养元素的分布特征,探讨了影响其分布的主要因素。长江口内外表层沉积物中的营养元素在河流段的分布波动较大,在口门附近海域分布较平缓。在三种营养元素中,IC、ON和IP分别为C、N、P的优势形态。在影响表层沉积物中营养元素分布的因素中,沉积物的粒度和上覆水体的盐度在其中起着重要的作用,同时还受到近岸排污和海洋生物生产的影响。  相似文献