黄渤海近海海藻养殖规模及固碳强度时空分布

定量研究黄渤海近海大型经济海藻的面积、产量及其固碳能力和空间分布,对海洋牧场建设和海藻固碳强度研究具有重要意义。基于2001—2016年《中国渔业统计年鉴》和2016年《山东渔业统计年鉴》数据,对2001—2015年黄渤海近海和全国近海养殖大型经济海藻的产量、面积及结构进行了对比分析,采用CCI指数计算了黄渤海近海及全国近海大型经济海藻的固碳能力,并分析了2016年山东省养殖海藻的空间分布特征。研究表明:2001—2015年海藻养殖面积、产量整体呈上升趋势,其中全国海藻养殖面积在2005—2007年,产量在2006—2007年出现间断性下降,黄渤海海藻养殖面积在2005—2007年,产量在2001—2003年、2005—2008年出现阶段性下降;黄渤海近海海藻养殖产量占全国近海海藻养殖产量年均约45.53%,固碳总量占全国海藻固碳总量年均约51.75%,其中裙带菜,海带及紫菜为黄渤海海藻养殖的主要经济藻类;以山东省为典型省份的海藻固碳强度在海岸带间表现出明显的空间分布差异,其中威海市荣成区域人工养殖海藻固碳总量最多。     

Quaternary stratal architecture of the Barcelona prodeltaic continental shelf (NW Mediterranean)

The Barcelona continental shelf is part of a 6–20 km wide canyon-bounded shelf located off the city of Barcelona (NE Spain). This study integrates newly acquired high-resolution single channel seismic reflection profiles and available lithological information of the Barcelona shelf to describe its late Quaternary architecture and the role of global glacio-eustatic fluctuations and local factors in its development.

Four major sequence boundaries are identified throughout the seismic dataset. They are tentatively correlated with the four last 4th order (100–120 ka) high-amplitude late Quaternary glacio-eustatic lowstands. Most of the stratigraphic record is formed by falling stage systems tracts with forced-regressive deposits, which confers a general progradational vertical stacking pattern. Transgressive systems tracts are represented by continuous units confined directly off river sources and on previously eroded surfaces. Stillstand deposits are difficult to recognize in the available dataset. The uppermost seismic unit corresponds to the Holocene shore-parallel Besos and Llobregat joint prodelta affected by the prevailing south-westward circulation.

The general architecture of the late Quaternary Barcelona shelf deposits is determined by global glacio-eustatic cycles. However, the lateral variability of the seismic units depends largely on local factors such as (i) the position of sediment sources (essentially the Llobregat River); (ii) differential subsidence and, especially, sediment compaction; (iii) erosive processes such as canyon incision, mass wasting or wave base dynamics; and (iv) underlying geomorphic restrictions.     

Effect of salinity on heavy metal mobility and availability in intertidal sediments of the Scheldt estuary

The effect of the flood water salinity on the mobility of heavy metals was studied for intertidal sediments of the Scheldt estuary (Belgium). Soils and sediments of 4 sampling sites were flooded with water of different salinities (0.5, 2.5, and 5 g NaCl L⁻¹). Metal concentrations were monitored in pore water and surface water. To study the potential effects of flood water salinity on metal bioavailability, duckweed (Lemna minor) was grown in the surface water. The salinity was found to primarily enhance the mobility of Cd and its uptake by duckweed. Cadmium concentrations in pore water of soils and sediments and surrounding surface waters significantly exceeded sanitation thresholds and quality standards during flooding of initially oxidized sediments. Moreover, the effect was observed already at lower salinities of 0.5 g NaCl L⁻¹. This implies that risks related to Cd uptake by organisms and Cd leaching to ground water are relevant when constructing flooding areas in the brackish zones of estuaries. These risks can be reduced by inducing sulphide precipitation because Cd is then immobilised as sulphide and its mobility becomes independent of flood water salinity. This could be achieved by permanently flooding the polluted sediments, because sulphates are sufficiently available in the river water of the brackish part of the estuary.     

Combined classifier–quantifier model: A 2-phases neural model for prediction of wave overtopping at coastal structures

A 2-phases neural prediction method for wave overtopping is developed. The ‘classifier’ predicts whether overtopping occurs or not, i.e. q = 0 or q > 0. If the classifier predicts overtopping q > 0, then the ‘quantifier’ is used to determine the mean overtopping discharge. The overtopping database set up within the EC project CLASH (De Rouck, J., Geeraerts, J., 2005. CLASH Final Report, Full Scientific and Technical Report, Ghent University, Belgium) is used to train the networks of the prediction method.     

Multielement analysis of deep-sea sediments by inductively coupled plasma mass spectrometry

Marine sediments were dissolved by HNO3-HF-HCIO4 in a sealed container at low pressure; I-IF was evaporated in an open container and salts were dissolved in HCl by heating, then transferred to 2% HNO3 solution. A total of 45 elements, including Li, Be, So, Ti, V, Cr, Mn, Co, Ni, Cu, Zn, Ga, Rb, Sr, Y, Zr, Nb, Mo, Cd, In, Sb, Cs, Ba, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Hf, Ta, W, TI, Pb, Bi, Th and U, were measured by inductively coupled plasma mass spectrometry (ICP-MS). Condi-tions and sample experiments showed that this procedure defines a good experimental method which has the advantages of clear interference, easy operation and reliable results. The concentrations of the 45 elements could be used for resource exploration, envi-ronmental assessment and academic research.     

STUDY ON FLUXES OF CH4 EMISSION FROM PADDY FIELDS IN CHANGCHUN AREA

CH4 is a kind of important greenhouse gases in atmosphere. The current atmospheric concentration of CH4 is about 1.7ppmv and is increasing at almost 2％ per year. The sources of CH4 include paddies, wetland and tundra, insects, the digestive tracts of ruminants, coal mining, biomass burning, and the leakage of natural gas. The total input to the atmosphere lies in the range 300－ 550Tg per year. CH4 from paddy fields is about 10％ － 20％ of total source of atmospheric CH4 (DING, 1997). …     

复方新诺明在鲈鱼体内的药物代谢动力学研究

首次报道了用高效液相色谱法研究鲈鱼口服复方新诺明的药物代谢动力学特征。结果表明 ,鲈鱼单次口服剂量为200×10-6的复方新诺明后 ,其血液药物浓度 时间数据符合一室开放动力学模型。药物代谢动力学参数 :吸收速率常数 (ka)为0.096h -1、达峰时间 (Tmax)为21.479h,峰浓度 (Cmax)为50.768μg/ml、吸收半衰期 (T(1/2)Ka)为7.250h、消除半衰期 (T(1/2)K)为38.299h,药时曲线下面积 (AUC)为4138.400(mg·h)/L。鲈鱼口服药物0.5h后在肌肉、血液、肝脏、肾脏4种组织中就可以检测到药物的存在。药物在16h采样点4种组织里的浓度达最高。药物在肌肉、血液、肝脏中的平均回收率约80%～90 % ,该方法的检测限可达0.05×10-6。     

赤道海洋波动弱非线性动力学系统浅析

通过对连续层化条件下赤道海洋波动及相关环流特征尺度和物理量的尺度分析,全面分析了赤道海洋波动及其相关环流所属动力学系统的性质。分析结果表明,该系统为以参数ε为表征的弱非线性动力学系统,在此基础上建立了适合描述赤道波非线性效应的动力学模型。     

An analysis of the spectrophotometric and photometric observations of comets 1967II, 1968I, 1968V,and 1968VI

Emission fluxes of CN, C₂ and C₃ carbon-bearing molecular species observed in the coma of comets Rudnicki (1967II), Ikeya-Seki (1968I), Whitaker-Thomas (1968V), and Honda (1968VI) are analysed in the framework of Haser model. CN, C₃ and C₃ production rates are determined using recently derived fluorescence efficiencies. The dependence of CN, C₂ and C₃ production rates on the heliocentric distance and the possible correlations among these radicals is studied. It is shown that comets Ikeya-Seki (1968I) and Honda (1968VI) have the same mean color indices (B-V) and (U-B).