印尼爪哇上升流海域次表层叶绿素最大值层的浮游植物色素分布特征

Upwelling occurs on the coast of Java between June and October, forced by local alongshore winds associated with the southeasterly monsoon. This causes variations in phytoplankton community composition in the upwelling zone compared with the surrounding offshore area. Based on pigments analysis with subsequent calculations of group contributions to total chlorophyll a(Chl a) using CHEMTAX, we studied the distribution and composition of phytoplankton assemblages in the subsurface chlorophyll maximum along the south coast of Java and the influence of upwelling. Nineteen phytoplankton pigments were identified using high-performance liquid chromatography, and CHEMTAX analysis associated these to ten major phytoplankton groups. The phytoplankton community in the coastal area influenced by upwelling was characterized by high Chl a and fucoxanthin concentrations, indicating the dominance of diatoms. In contrast, in the offshore area, the Chl a and fucoxanthin concentrations declined to very low levels and the community was dominated by haptophytes represented by 19′-Hexanoyloxyfucoxanthin. Accordingly, microphytoplankton was found to be the major size class in the coastal area influenced by upwelling, while nanophytoplankton was most abundant in the offshore area. Low concentrations of other accessory pigments indicated less contribution from dinoflagellates,prasinophytes, chlorophytes and cryptophytes. Photo-pigment indices revealed that photosynthetic carotenoids(PSCs) were the largest component of the pigment pool, exceeding the proportion of Chl a, with the average PSCTP up to 0.62. These distribution trends can mainly be explained by phytoplankton adaption strategies to upwelling and subsurface conditions by changing species composition and adjusting the pigment pool.     

未来相对海平面变化对山东沿海港口的影响

以山东省沿海港口为研究对象,采用基于IPCC第五次评价中RCP8.5情景的渤海、黄海海平面上升速率数据和山东省沿海地区地壳垂直运动速率数据,估算各港区自2019年到2100年相对海平面上升数据,获得以下研究结果:滨州港为0.956 m,东营港为0.794m,潍坊港为0.47 m,龙口港为0.308 m,日照港为0.18...     

用最小二乘法分析胶州湾海流特征

在胶州湾湾口、西侧、中心、东侧、北侧湾顶五个区域布设测站,利用2018年冬季至2020年秋季潮位、海流等监测数据,基于最小二乘法进行调和分析计算,并结合垂线平均流速流向、可能最大流速、水质点可能最大运移距离等计算模型,研究分析了胶州湾海流特征。结果表明,各区域潮流类型系数均小于0.5,M₂分潮椭圆率绝对值均不超过0.1,接近于0,故胶州湾潮流性质为正规半日潮流,潮流运动形式以往复型为主。湾口区域余流、可能最大流速、水质点可能最大运移位移均最大。不同季节余流流速和流向的差异没有明显的规律性,除湾区西侧测站外,其余位置不同季节余流流向整体上有固定朝向：湾口处东偏北、中心站西偏北、东侧站南偏东、北侧湾顶站东偏北。靠近岸边的湾口、东侧和北侧湾顶站余流流向与邻近海岸垂直。在垂直方向上,各测站可能最大流速和水质点可能最大运移距离由表层至底层整体上呈减小趋势,流向基本一致。     

Periodic spectral characteristics of seismicity before strong earthquakes and their application

IntroductionMaximumentropyspectralmethod(MEM)(Burg,1972)hadbeenamethodusuallyusedinstudyingtheseismicityanditsmainpurposeistofindthedominantspectrainthelong-termseismicityprocessesinthepastyears(Zhu,1985).Inthispaper,themethodisappliedtostudywhethertherearesomespecialspectraofseismicityinsomespecificstagesinearthquake-generatingprocesses.Sowestudyseparatelythenormalandabnormalstageofearthquakeactivity,whoseactiveprocessisregardedasstablestochasticprocess,inordertofindtheirspectracharactersan…     

华北石炭、二叠系高分辨层序地层分析

通过以露头、测井曲线和岩芯观察为基础的高分辨层序地层分析,认为华北石炭、二叠系为1个大层序,时限约为310～250Ma。以早二叠世紫松期与隆林期之交的285Ma的区域性不整合面为界,分为Ms1、Ms2两个中层序。Ms1穿过了石炭、二叠系的年代地层界线（295Ma）。含煤的本溪、太原、山西组（308～275Ma）分为6个层序组（Ss1－6）,包括19个层序（CSq17,PSq1-12）。通过区域性层序地层单位的对比,在生物年代地层格架的基础上,建立了更精细的等时地层格架。晚石炭世沉积仅分布在华北中部及北部,南华北缺失CSq1-7,豫西还缺失PSq1-3。层序之间的不整合面、岩石地层单位和主要煤层在大区域内都是穿时的。晚石炭世海水自东向西侵入华北北部,向西和向南超覆;紫松或海水自晋西南和苏皖北部向北入侵,为华北晚古生代的最大海侵;隆林晚期海侵较隆林早期海侵略大。太原组的主煤层在山西自南向北形成于紫松早期海平面缓慢上升过程中,内蒙古南部山西组的巨厚煤层形成于最大海侵时期,山西省山西组的主煤层自北向南形成于隆林早期,晋东南至南华北山西组的主煤层形成于栖霞早期。通过三交、柳林矿区煤相分析表明海侵体系域底部的煤层比高位体系域的煤层更富生烃潜力,是一种新的成煤模式,也是煤层气找矿勘探应该     

辐射熏烟浓度预测研究

讨论了辐射熏烟过程及其浓度预测中的几个问题,介绍了熏烟地面浓度绝对最大值及其空间分布的正确计算方法。分析了影响它们的各种因素和高浓度区的延伸范围。     

藏北高原D110点土壤温度的极值分析

通过藏北高原Ｄ１１０点一年中不同深度的日最高值、日最低值及日温差的分析,表明从０ｃｍ￣４０ｃｍ,土壤温度的日最高值的变化剧烈,而日最低值的变化则相对平稳,冬半年土壤温度的日最低值、日最高值比较接近,日温差较小,而且它们随时间的变化比较平稳;但夏半年（５￣９月）波动较冬半年的大,且最高温的波动要比最低温的波动大得多;随深度的增加日温差减小,在８０ｃｍ深处已基本上看不到日温差的变化。     

中国近50年严冬和冷夏演变趋势与区划

以中国９３个测站１９５３～１９９５年冬季平均最低气温（Ｔｍ）和夏季平均最高气温（ＴＭ）的长期变化趋势及年际、年代际变率特征为研究对象,利用旋转经验正交函数（ＲＥＯＦ）对冬季Ｔｍ和夏季ＴＭ进行客观区划,揭示了我国近半个世纪冷夏、严冬气候异常的变化规律,为进一步研究短期气候预测方法提供了依据     

海浪方向谱估计方法的比较

分别利用数值模拟和实测资料对目前被认为分辨力较高的最大似然法(MLM)、扩展本征矢方法(EEV)、扩展最大滴方法(EMEP)以及贝叶斯方法(BDM)等四种海浪方向谱估计方法的可靠性进行了分析,从不同频率、不同噪声水平和不同方向集中度三个角度检验其再现性、稳定性和实用性,结果表明MLM、EEV和BDM大致给出相同的方向分布,其中BDM的再现性最好,但实用性逊于MLM和EEV,EMEP由于稳定性差,不适用于实测资料的分析.     

Application of MEP Method to the Study of Statistical Properties of Random Waves

—The maximum entropy principle(MEP)method and the corresponding probability evaluationmethod are introduced,and the maximum entropy probability distribution expression is deduced in mo-ment of the second order.Fully developed wave height distribution in deep water and wave height and peri-od distribution for different depths in wind wave channel experiment are obtained from the MEP method,and the results are compared with the distribution and the experimental histogram.The waveheight and period distribution for the Lianyungang port is also obtained by the MEP method,and the re-sults are compared with the Weibull distribution and the field histogram.