七带石斑鱼(Epinephelus septemfasciaius)两个野生群体形态差异分析

对2种不同地理种群七带石斑鱼进行14项形态性状的测定,采用2种多元统计分析方法和t-检验方法,比较了2个群体的外部形态特征.t-检验结果表明,2群体在14个性状中有12个性状表现出极其显著差异(P＜0.01),1个性状表现出差异显著(P＜0.05).主成分分析构建了3个反映形态特征信息的综合性指标--主成分1、主成分2和主成分3,三者的贡献率分别为29.873%、25.091%和16.875%.三个主成分的累积贡献率为71.804%,2群体之间存在明显的偏离态势,形成两个不同的类群,2群体在主成分l轴上的差异较在主成分2轴上的差异更为明显,主成分1主要由经t-检验差异指标数量多和差异程度大的性状组成.判别分析表明,2个七带石斑鱼群体的形态差异显著(P＜0.0001),建立了2个群体的判别函数,其判别准确率及综合判别率均为100%,可以认为逐步判别法对七带石斑鱼不同群体的初步鉴定是可行的.差异系数(CD)计算的结果表明,尽管2群体在形态上存在一定的差异,但尚未达到亚种水平.主成分分析、t-检验和判别分析的结论基本上是类似的,它们从不同的角度反映了群体间的形态学差异.     

Nonlinear influences on ocean waves observed by X-band radar

The purpose of this study is to discuss the influence of signal nonlinearity upon X-band radar observations. A method for estimating the degree of nonlinearity by bispectral analysis was applied and discussed. We found that bispectral analyses from spatial radar backscatter series are similar to results obtained from water level time series. In addition, the average nonlinear degree from radar backscatter is related to wind speed. The accuracy of wave observations derived by consideration of the nonlinear effect from radar backscatter was also investigated. The estimated error in wave height from the radar data is also related to the degree of nonlinearity. In order to improve accuracy, the modulation transfer function method was applied in order to eliminate the influence of nonlinearity.     

海水人工湿地系统脱氮效果与基质酶活性的相关性

利用海水人工湿地系统处理海水养殖外排水,分析了人工湿地对不同形态氮的净化效果,探讨了人工湿地表层基质酶活性变化及其对系统脱氮效果的影响。选取互花米草作为人工湿地植物,煤渣、珊瑚石和细砂作为人工湿地基质,实验期间连续进水,系统运行稳定。研究结果表明:海水人工湿地系统对氨氮(NH4-N)、亚硝态氮(NO2-N)、硝态氮(NO3-N)、总氮(TN)和可溶性有机氮(DON)去除效果显著,去除率分别为(99.6±0.7)%、(99.9±0.0)%、(98.2±2.0)%、(92.6±1.5)%和(86.1±4.8)%。人工湿地表层基质下行池脱氢酶、硝酸还原酶和脲酶的酶活性均高于上行池,下行池对污染物的去除效果更好。脱氢酶活性与海水人工湿地系统氨氮的去除有关;硝酸还原酶活性影响着海水人工湿地硝态氮的去除;脲酶活性与人工湿地总氮和硝态氮的去除存在明显相关趋势。下行池硝酸还原酶和脲酶的酶活性间具有显著相关性(r=0.76, P0.05)。人工湿地微生物种类丰富,下行池微生物多样性高于上行池,植物根部微生物多样性最高,提高了系统脱氮的效率。上述研究结果将有助于阐明海水人工湿地系统中不同形态氮的迁移转化机理。     

Photosynthetic response of floating Ulva prolifera to diurnal changes of in-situ environments on the sea surface

During yellow sea green tide outbreak, the thalli of Ulva prolifera drifted more than 350 km on the sea surface from off shore of Jiangsu Province to Qingdao city, where they were exposed to complex changes of local environments. The purpose of this study is to investigate the response of the thalli to diurnal changes of environments on the sea surface, and a sea surface environment simulator (SSES) was designed to simulate the natural environment of floating U . prolifera mat. A control experiment is designed in the laboratory, which was processed under suitable conditions (20°C for temperature, 72 μmol photons/(m 2 ·s) for light intensity and 30 for salinity), and an in-situ research was conducted to study the photosynthetic responses of floating U . prolifera to diurnal changes of environments. The results show that the photosynthetic efficiency of the thalli decreased gradually with time, and decreased rapidly after 14:00 local time (LT). After exposed to the environment on the sea surface for 6 h, the photosynthetic activity of the thalli decreased significantly. Furthermore, physiological-level and molecular-level experiments revealed that non-photochemical quenching (NPQ), cyclic electron flow (CEF) and energy redistribution between PSI and PSII all played an important role in the strong photosynthetic plasticity of U . prolifera . NPQ is the most important photoprotective responses to environmental changes before 12:00 LT. The results also confirmed that the CEF and energy redistribution between PSI and PSII are the main synergistic eff ects for the thalli to adapt to the environmental changes when the process NPQ cannot work. And the result can further reveal the reason why U . prolifera can adapt to the living condition of long distance drift on the sea surface. The findings of this research could provide a theoretical basis for explaining outbreaks of the green tide and instructing the management of the problem.     

大菱鲆(Scophthalmus maximus)四个不同地理群体数量形态特征比较

采用聚类分析、单因子方差分析和主成分分析方法,对4个不同地理群体大菱鲆进行了12项形态性状的测定,比较了4个群体的外部形态特征。聚类分析结果表明,4种大菱鲆群体中,丹麦和挪威之间及英国和法国之间的差异较小,丹麦、挪威和英国、法国之间的差异较大。方差分析多重比较结果表明,4个群体在部分形态特征上表现出明显差异,其中,英国和法国群体、挪威和丹麦群体之间形态特征差异显著指标较少,丹麦群体和英国群体、丹麦群体和法国群体、挪成群体和英国群体、挪威群体和法国群体之间差异显著指标较多。主成分分析构建了3个反映形态特征信息的综合性指标——主成分1、主成分2和主成分3,三者的贡献率分别为38.663%、14.117%和8.976%,三个主成分的累积贡献率为61.756%.分析结果显示,英国和法国群体、挪威和丹麦群体之间形态差异不显著,丹麦群体和英国群体、丹麦群体和法国群体、挪威群体和英国群体、挪威群体和法国群体之间形态差异显著,且差异主要来源于主成分1,而主成分1主要由经方差分析多重比较差异显著的指标组成,显然,主成分分析与聚类分析、方差分析的结论基本上是类似的,它们从不同的角度反映了群体间的形态学差异.     

基于模糊决策理论的重力辅助导航区域选择方法

针对传统重力辅助导航区域选择方法仅利用单一评价指标所导致的评价结果不全面这一缺陷,提出一种基于模糊决策的多指标综合选取方法。首先,应用该方法计算目标区域重力异常的标准差、粗糙度、相关系数、重力信息熵和重力坡度等表征重力特征的统计参量;然后,利用模糊决策理论方法求解出指标的隶属度矩阵和权阵,得到区域总的评价指数;最后,依据总评价指数进行匹配区选择。仿真结果表明,本方法具有较好的可靠性,评价指数高的区域,其匹配效果更好。     

固相吸附毒素跟踪技术(SPATT)在浙江南麂海域的应用

浙江南麂岛海域是我国近岸贝类的重点养殖区,近年来一直遭受脂溶性贝类毒素(lipophilic shellfish toxins,LSTs)的污染,威胁着人类健康。为了建立有效的食品安全预警方法,本研究利用固相吸附毒素跟踪技术(solid phase adsorption toxin tracking,SPATT)在该海域进行了为期一年的野外监测和LSTs毒素分析。结果表明:7种LSTs毒素在SPATT(DIAION?HP20)中被检出,分别是大田软海绵酸(okadaic acid,OA)、鳍藻毒素-1(dinophysistoxin-1,DTX-1)、虾夷扇贝毒素(yessotoxin,YTX)及其衍生物homo YTX、扇贝毒素-2(pectenotoxin-2,PTX-2)及其衍生物7-epi-PTX2sa和环亚胺毒素(gymnodimine,GYM);有8种毒素在厚壳贻贝(Mytilus galloprovincialis)中被检出,分别是OA、DTX1、homo YTX、PTX2、7-epi-PTX2sa、GYM、原多甲藻酸贝类毒素-3(azaspiracid-3,AZA-3)和虾夷扇贝毒素衍生物45-OH-homo YTX。整体而言,SPATT(HP20)中吸附的毒素种类与贝肉中监测出的毒素种类大体上一致,且两者间OA、DTX1和PTX2的浓度在时间上具有较好的相关性,可见SPATT(HP20)对这些LSTs毒素具有较高的灵敏度,有望作为水体中LSTs毒素的预警监测材料。南麂岛海域LSTs分布特征明显,夏季最高,其次是春秋季,冬季最低,其中2014年夏季贝肉中OA毒素含量高达77.19ng/g贝肉,超出国家限量标准(45ng/g贝肉)比例达11.76%,为浙江南麂海域贻贝的食用安全带来隐患。     

西湖凹陷孔雀亭气田成藏主控因素

综合运用地质、钻井、生物标志物、碳同位素、储层流体包裹体等资料,在油气分布特征和来源分析的基础上,探讨了控制西湖凹陷孔雀亭气田油气成藏及富集的主要因素。研究结果表明,孔雀亭气田油气主要分布在始新统平湖组储层内,具有"上油下气"的纵向分布特征,以断块型凝析气藏为主,原油及天然气来源于自身和西部次洼平湖组源岩联合供烃。孔雀亭气田油气成藏及富集主要受断层封堵性、砂体厚度和储层物性及流体充注历史的联合控制,断层封堵性控制了油气藏的含油气性,砂体厚度和储层物性制约了油气层厚度和含油气饱和度,流体充注历史决定了油气藏的现今赋存相态。