Are Global Tide Gauge Data Stationary in Variance?

Tide gauges distributed all over the world provide valuable information for monitoring mean sea level changes. The statistical models used in estimating sea level change from the tide gauge data assume implicitly that the random model components are stationary in variance. We show that for a large number of global tide gauge data this is not the case for the seasonal part using a variate-differencing algorithm. This finding is important for assessing the reliability of the present estimates of mean sea level changes because nonstationarity of the data may have marked impact on the sea level rate estimates, especially, for the data from short records.     

A preliminary study of carbon system in the East China Sea

In the central part of the East China Sea, the activity of CO₂ in the surface water and total carbonate, pH and alkalinity in the water column were determined in winter and autumn of 1993. The activity of CO₂ in the continental shelf water was about 50 ppm lower than that of surface air. This decrease corresponds to the absorption of about 40 gC/m²/yr of atmospheric CO₂ in the coastal zone or 1 GtC/yr in the global continental shelf, if this rate is applicable to entire coastal seas. The normalized total carbonate contents were higher in the water near the coast and near the bottom. This increase toward the bottom may be due to the organic matter deposited on the bottom. This conclusion is supported by the distribution of pH. The normalized alkalinity distribution also showed higher values in the near-coast water, but in the surface water, indicating the supply of bicarbonate from river water. The residence time of the East China Sea water, including the Yellow Sea water, has been calculated to be about 0.8 yr from the excess alkalinity and the alkalinity input. Using this residence time and the excess carbonate, we can estimate that the amount of dissolved carbonate transported from the coastal zone to the oceanic basin is about 70 gC/m²/yr or 2 GtC/yr/area-of-global-continental-shelf. This also means that the rivers transport carbon to the oceans at a rate of 30 gC/m²/yr of the coastal sea or 0.8 GtC/yr/ area-of-global shelf, the carbon consisting of dissolved inorganic carbonate and terrestrial organic carbon decomposed on the continental shelf.     

埕岛油田数据基础重组及开发应用

从数据管理及后期应用的角度提出了数据平台的要领，讨论了该数据平台的物理结构、逻辑结构，在分类与组织的基础上给出了相应的数据字典。同时，还基于该平台探讨了测井曲线库及图形库的建设方法，并实现了具体功能。     

进入渤海的热带气旋路径特点分析

热带气旋是夏季影响渤海的灾害性天气系统之一。其影响路径主要有三类，各类路径在影响时前期中高纬500hPa高空环流形势及夏季西太平洋副热带高压特征指数有显著差异。     

Coupling of life cycles of the copepods Calanus chilensis and Centropages brachiatus to upwelling induced variability in the central-southern region of Chile

A time series of zooplankton sampling carried out at Station 18 off Concepción (36°S, 73°W) from August 2002 to December 2003 allowed the study of annual life cycles of the copepods Calanus chilensis and Centropages brachiatus in association with environmental variability in the coastal upwelling zone. Changes in the abundance of eggs, nauplii, and copepodids were assessed from samples taken at a mean time interval of ca. 20 days. Upwelling variability in near-surface waters was reflected in seasonal changes in salinity, water column stratification, and oxycline depth, as well as a weak seasonal signal in sea surface temperature (1-2 °C). Both copepods exhibited similar life cycles, characterized by continuous reproduction throughout the year. Estimates of generation times, as a function of temperature, were 25-30 days for C. chilensis and 27-35 days for C. brachiatus, predicting about 12 and 10 generations a year, respectively. These estimates were consistent with reproduction pulses observed in the field. It was thus suggested that copepods may grow under non-limiting food conditions in this upwelling area. However, despite continuous reproduction, there were abrupt changes in population sizes along with the disappearance of early naupliar and copepodid stages taking place even during the upwelling season (spring/summer). These changes were attributed to sudden increases in mortality taking place in spring or early summer, after which the populations remained at low levels through the fall and winter. It is thus suggested that, in addition to variability in the physical environment, biological interactions modulating changes in copepod mortality should be considered for understanding copepod life cycles in highly productive upwelling systems.     

风力对内陆浅水水域磷水平的影响

本文通过对平度市大泽山水库(面积约0.5平方公里,平均水深约1.5米)的实地观测,研究了风力对内陆浅水水域磷水平的影响。结果表明,影响程度取决于风速、风力作用时间、水深以及风力作用前磷水平的高低等因素。就大泽山水库而言,风速大于2.5米/秒的风力可引起各种形态磷的明显增加。不过对磷酸盐磷来说,如果浓度本来就较高,风力作用下当有大量沉积物颗粒泛起时,会对PO_4~≡产生吸附,因而可能导致水中游离磷酸盐磷含量下降。鉴于此,作者建议对内陆浅水水域进行磷水平调查时应考虑风力的作用。     

棉粕蛋白酶解物对异育银鲫(Carassius auratus gibelio)消化、生长和胰蛋白酶mRNA表达量的影响

以棉粕蛋白为酶解底物,用枯草杆菌蛋白酶对其进行酶解,以酶解产物1.5%和3.0%两个梯度等量替代鱼饲料配方中棉粕,在室内流水养殖系统中喂养异育银鲫鱼种[体重为(30±2)g]65天。测定鱼的生长、营养物质表观消化率、消化蛋白酶活性及肝胰脏中胰蛋白酶mRNA表达水平等指标。结果表明,添加1.5%和3.0%棉粕酶解产物的鱼在饲养35天后的特定增长率(SGR)分别比对照组高32.5%和56.7%,且差异显著(P<0.05);在饲养65天后,两组特定增长率分别比对照组高8.0%和21.0%,且差异极显著(P<0.01),肝胰脏中胰蛋白酶mRNA表达水平也随棉粕酶解产物添加梯度提高而相应提高,表明鱼的生长与消化蛋白酶mRNA表达水平相关。同时棉粕蛋白酶解物对肠道蛋白酶的活性和营养物质表观消化率都有促进作用,而棉粕蛋白酶解物对鱼肌肉成分并没有改变,这也表明棉粕蛋白酶解物在促进鱼生长、内源酶活性同时并未降低鱼的品质。     

龙口平均海平面变化原因的研究

本文通过对实测海平面高度的对比，发现龙口平均海平面从１９９１年起有明显的升高趋势。作者猜测此乃龙口在码头扩建后有系统下沉所致。     

SSA1—1型声学水位在长江口潮位站的应用

本文介绍了长江口区水文泥沙概况，举例说明了ＳＳＡ１－１型声水位计在崇头潮位站比测试验和投产应用情况，结果表明该水位计是收集长江口区潮位资料较理想的仪器。