Energy flow in Branchiura sowerbyi (Oligochaeta: tubificidae) in a shallow macrophyte-dominated lake, Biandantang Lake

The energy flow ofBranchiura sowerbyi was studied for the first time in China in a shallow macrophytic lake, Biandantang Lake, Hubei Province. The energy flow was calculated from the measurement of flesh production (12.5241kJ/m²a), egestion (517.7302kJ/m²a), metabolism (38.3273 kJ/m²a), and excretion (4.3798kJ/m²a). The net growth efficiency of the species is about 22.7%, which accords well with the generally reported value for oligochaetes. In addition, the relationship between starvation respiration (R, mgO₂/ind·d), wet weight (Ww, mg) and temperature (T, °C) were also measured, with the regression function beingR=0.008Ww^0.736 e^0.050T. Project supported by NSFC (30270278, 3960019), the foundation of the government of Hubei Province (No. 2000J109), and the foundation of Ecological Station, CAS in the Institute of Hydrobiology.     

ENVISAT测高数据波形重跟踪分析研究

对卫星测高技术中的波形重跟踪技术及其算法进行了详细分析讨论．同时分析了波形重跟踪中最小二乘解初值及权的确定,根据ENVISAT的SGDR波形数据,利用波形重跟踪技术研究了开阔海域上的距离改正情况(一般距离改正为20～30cm)。结果表明,重跟踪改正后的精度,18Hz距离优于1Hz距离。     

中国地震电磁现象的观测与研究

对近年来中国地震电磁现象(包括地面电磁场、大气电场、地磁脉冲和电离层扰动等)的观测研究进行了重点介绍。     

CHARACTERISTICS OF ZONAL ANOMALY OF ANNUAL PRECIPITATION IN THE NORTHEASTERN CHINA

The characteristics of zonal anomaly and change rule of temporal distribution of annual precipitation in the northeastern China are revealed in this paper with EOF (Empirical Orthogonal Function) and REOF (Rotated Empirical Orthogonal Function) methods and results are drawn in the standard relief maps with GIS technology for practical application. Data used in the study were obtained from 208 meteorological stations over the northeastern China from 1961 to 2001. EOF results show that the first 3 loading vectors could give entire spatial anomaly structure of annual precipitation. In the Northeast Plain including the Songneng Plain and the Liaohe Plain, there is a regional compatibility (whether wet or dry) of annual precipitation change and this precipitation pattern has occurred since the late 1980s to the present. There also exist annual precipitation patterns of wet (or dry) in south and dry (or wet) in north and wet (or dry) in east and dry (or wet) in west. REOF results display 8 principal precipitation anomaly areas by the first 8 rotated loading vectors: the west plain, the Liaodong hills, the Sanjiang Plain, the Liaoxi hills,the Changbai Mountains, the Hulun Buir Plateau, the southwest plateau and the Liaodong Peninsula.     

Effect of growth phase on the fatty acid compositions of four species of marine diatoms

The fatty acid compositions of four species of marine diatoms (Chaetoceros gracilis MACC/B13, Cylindrotheca fusiformis MACC/B211, Phaeodactylum tricornutum MACC/B221 and Nitzschia closterium MACC/B222), cultivated at 22 ℃±1 ℃ with the salinity of 28 in f/2 medium and harvested in the exponential growth phase, the early stationary phase and the late stationary phase, were determined. The results showed that growth phase has significant effect on most fatty acid contents in the four species of marine diatoms. The proportions of 16:0 and 16: 1n-7 fatty acids increased while those of 16 :3n-4 and eicosapentaenoic acid (EPA) decreased with increasing culture age in all species studied. The subtotal of saturated fatty acids (SFA) increased with the increasing culture age in all species with the exception of B13. The subtotal of monounsaturated fatty acids (MUFA) increased while that of polyunsaturated fatty acids (PUFA) decreased with culture age in the four species of marine diatoms. MUFA reached their lowest value in the exponential growth phase, whereas PUFA reached their highest value in the same phase.     

Morphological and toxicity characteristics of Pseudo-nitzschia pungens strain PP0201-01 isolated from the East China Sea

The morphology and toxicity ofPseudo-nitzschia strain PP0201-01, isolated near the estuary of Changjiang (Yangtze) River in Year 2002 and tentatively identified asPseudo-nitzschia pungens, were studied. The strain was identified morphologically asP. pungens using scanning electronic microscope (SEM). The analytical results of LC-PDA (liquid chromatography with photodiode array detector), LC-MS (liquid chromatography with mass detector), and the toxicity data from mouse bioassay, showed that no domoic acid was produced by the strain. However, the mechanism of domoic acid production byPseudo-nitzschia species is complicated. More works are needed to assess the toxic species and to evaluate the potential risk of amnesic shellfish poisoning (ASP) in China. Supported by the projects of Ministry of Science and Technology (No. 2001CB409704 and No. 2001BA804A20), and the innovation project of the Institute of Oceanology, CAS (No. 200223107).     

体视化关键技术

体视化技术有着广泛的应用前景。对体视化的几种关键技术进行了分类综述，介绍了体数据的表示和分类，面绘制、体绘制和混合绘制各类典型算法的原理和特点。体数据的表示方式涉及到表示精度、存储量和处理时间之间的矛盾，要根据实际问题的具体特点和要求加以选择。体数据的分类是整个可视化算法中的一个关键步骤。只有对体数据进行准确的分类，才能经过处理得出合理的图像。近年来为加快绘制速度和提高图像质量提出了许多改进的体视化算法，并对部分改进算法进行了介绍。     

G-凸空间内的连续选择定理和重合点定理

在G-凸空间内得到了一些新的连续选择定理,并利用连续选择定理证明了非紧G-凸空间内及乘积G-凸空间内的重合点定理.这些定理改进并推广了最近文献中的一些已知结果.     

浅议矿产资源的知识产权保护

矿产资源是自然资源的重要组成部分,是人类赖以生存的物质基础,是国家安全与经济发展的重要保证。重视矿产资源勘查、开发、利用中的知识产权保护,对于国家的长远发展,维护国家利益具有重要意义。