南海北部坡折带溶解氧分布特征及理化环境因子影响     

杨阳  马媛  史华明 《海洋学报》2013,35(1):104-110

依据2010年1月南海北部坡折带冬季航次资料,发现150~1 000 m层溶解氧表现出东北高、西南低的分布特征,在垂向上溶解氧整体上呈由表至底逐渐降低趋势。在强烈的水交换作用下溶解氧浓度大于8 mg/dm3等值线占据50 m以浅海域。中尺度暖涡在很大程度上改变了中下层海水中溶解氧空间分布,150~1 000 m层暖涡中心附近海域的溶解氧含量显著高于周边未受或受暖涡影响较小的海域,此外,溶解氧与营养盐、温度、盐度、pH之间在不同层次上存在明显的相关性,表明该海域冬季溶解氧的分布受物理过程和生化过程的影响。  相似文献   

南海北部大鹏湾中DOP的分布、滞留时间、自养生产和异养降解     

史华明  马玉  李绪录  石晓勇  张军晓 《海洋学报(英文版)》2019,38(8):17-26

The importance of dissolved organic phosphorus(DOP) as a potential nutrient source for primary producers in marine systems has been recognized for up to eight decades, but currently, the understanding of the biogeochemistry of DOP is in its infancy. In the present study, monthly data between 2000 and 2014 were used to analyze the temporal and spatial distributions of DOP in the Mir Bay, the northern South China Sea. The DOP residence time(T_(DOP)) was also investigated using a simple regression analysis in combination with chlorophyll a(Chl a) measurements while excess DOP(ΔDOP), produced by the biogeochemical processes of autotrophic production and heterotrophic removal, was determined using a two-component mixing mass-balance model in combination with salinity measurements. The results showed that the DOP concentration was(0.017±0.010) mg/L higher in the surface-water compared with the bottom-water and higher in the inner Tolo Harbour and waters adjacent to Shatoujiao compared with the main zone of the bay. Although seasonal changes and annual variability in the DOP were small, the surface DOP concentration was higher in the wet season(April–September)than in the dry season(October–March) due to the impacts of seaward discharges and atmospheric deposition into the bay. Measurement and regression results showed that the DOP release rate from phytoplankton production was about 1.83(gP)/(gChl a) and the T_(DOP) was about 7 d, which implied that the DOP cycle in the bay was rapid. The ΔDOP was calculated from the model to be about 0.000 mg/L in the main zone of the bay and about 0.002 mg/L in the inner Tolo Harbour and waters adjacent to Shaotoujiao, suggesting that the autotrophic production of DOP was almost balanced by the heterotrophic removal in the main zone of the bay and dominated in the inner Tolo Harbour and waters adjacent to Shaotoujiao. In conclusion, the Mirs Bay is very productive and fairly heterotrophic.  相似文献   

夏季琼州海峡表层海水二氧化碳分压时空变化     

马玉  廖世智  李锐祥  蔡钰灿  曹永港  许春玲  史华明  王迪  许欣 《海洋学报》2020,42(12):110-118

采用船载海?气CO₂连续观测系统于2011年和2014年夏季在琼州海峡开展了现场观测，分析研究了表层海水二氧化碳分压(pCO₂)时空变化及其影响因子。2011年和2014年夏季pCO₂分别为(516±29) μatm和(533±15) μatm，海?气CO₂交换通量分别为(8.4±1.7) mmol/(m2·d)和(4.5±0.4) mmol/(m2·d)，均是大气CO₂的强源，高于相邻及相似海域，主要受控于东口海域上升流和海峡中部狭管效应。2011年夏季东口上升流增大pCO₂的同时也促进了浮游植物繁殖，光合作用吸收水体CO₂，降低了pCO₂，而且受其影响，西口口门附近叶绿素a和溶解氧含量陡增，pCO₂突降。2014年夏季东口海域上升流较弱，且观测海域垂直混合作用显著，pCO₂和溶解氧分布特征与2001年夏季明显不同。海峡中部狭管效应造成水体输运速率大、混合作用强，浮游植物“来不及”生长，pCO₂较高。  相似文献   

浒苔对不同氮源吸收特性的初步研究   总被引：2，自引：0，他引：2       下载免费PDF全文

吴婷  田小亭  刘召辉  石晓勇  史华明 《海洋科学》2011,35(4):51-54

采用Michaelis-Menten动力学方法,研究了浒苔对NO<,3>-N、NH<,4>-N和CO(NH<,2>)<,2>吸收利用关系.结果显示,浒苔对三种不同氮源的K<,s>(表观米氏常数)大小顺序为:NO<,3>-N>NH<,4>-N>CO(NH<,2>)<,2>,表明浒苔对有机氮的亲和力大于对无机氮的亲和力,且...  相似文献   

南海北部水团及中尺度现象对营养盐时空分布的影响     

张金尚  邹定辉  马玉  李锐祥  刘愉强  孟强  刘同木  史华明 《热带海洋学报》2023,(1):168-181

2019年在南海北部开展了4个季节的现场调查,获取了调查海域海水温度、盐度和营养盐等环境要素的实测数据。珠江口西侧近岸海域营养盐表现出明显的季节性和区域特征,除秋季为潜在的氮限制外,冬、春、夏季均表现为磷限制,且春季最为显著,主要受冲淡水输入和陆架水入侵影响。受西南季风强弱和调查海域海底地形差异的影响,春、夏季珠江口外跨陆架断面(A断面)上升流强度大于海南岛以东跨陆架断面(B断面),且夏季营养盐浓度等值线的爬升高度和范围大于春季。黑潮水入侵稀释了陆架坡折处以外海域的营养盐浓度,冬季75～150m深水体的营养盐浓度相比夏季降低了25%以上;El Ni?o期间黑潮水入侵增强,春、秋季A断面的东沙群岛附近海域75～150m深水体的营养盐浓度比相邻站位均低20%以上。春季冷涡中心无机氮(dissolved inorganic nitrogen,DIN)、磷酸盐(PO₄^3–-P)和硅酸盐(Si O₃^2–-Si)相较于边缘区域分别升高了6.42μmol·L^–1、0.71μmol·L  相似文献