基于数字全息显微的海洋浮游生物三维形貌快速重建方法研究

针对海洋浮游生物实时探测中,三维形貌特征难以快速获取的问题,本文提出了一种海洋浮游生物三维形貌快速重建的方法。基于离轴菲涅尔数字全息显微系统,通过改进相位恢复方法预消除相位畸变,直接得到正确的相位信息,进而对浮游生物三维形貌重建。该方法不需要进行后期复杂的相位补偿计算,就可以对浮游生物三维形貌进行快速重建,有利于对动态、微小尺寸的浮游生物进行实时探测及分析。论文对青岛近海岸浮游生物桡足类和夜光虫进行了三维形貌重建,分辨率可达到3.5μm。实验结果为离轴菲涅尔数字全息显微系统用于海洋浮游生物原位、实时探测的可行性提供了依据。     

泉州湾赤潮藻类优势种演替影响因子探讨

于2006年5—11月对东海泉州湾赤潮监控区设定4个采样站位,进行赤潮常规监测。结果表明,泉州湾藻类优势种由中肋骨条藻(Skeletonema costatum)、太平洋海链藻(Thalassiosira pacifica)、微小原甲藻(Prorocentrum minimum)、尖刺拟菱形藻(Pseudo-nitzschia pungens)、丹麦细柱藻(Leptocylindrus danicus)及旋链角毛藻(Chaetoceros curvisetus)等赤潮生物组成,虽然中肋骨条藻为最主要的优势种,但有3个站位出现了上述优势种的演替。通过深入分析该海域水质营养盐含量及组成结构的动态变化对赤潮藻类优势种演替的影响,发现由于不同的赤潮藻类种群具有各自的生态习性及适应环境的生长增殖策略,海域水质营养盐含量和组成结构的变化,会引起赤潮藻类种群增殖竞争力间强弱的相对变化,而种群增殖竞争力强的种类有可能迅速增殖取代原有的优势种而演替为新的优势种,这是一个动态的过程。     

低轨卫星初始状态误差对反演地球重力场的影响

基于动力学法反演地球重力场的基本理论,研究了卫星初始状态向量误差对应用低轨卫星精密轨道数据反演地球重力场的影响。在仅考虑低轨卫星初始状态误差的情况下进行了模拟计算,结果表明:在利用低轨卫星精密轨道数据反演地球重力场时,卫星初始状态向量误差需要重新进行估计;在目前的轨道精度水平下,若不顾及误差方程二次项的影响,反演弧长不宜过长;卫星初始状态速度误差(约1.5mm/s)的影响要大于位置误差(约10 cm)的影响。     

Global distribution of summer chlorophyll blooms in the oligotrophic gyres

Chlorophyll blooms consistently develop in the oligotrophic NE Pacific in late summer, isolated from land masses and sources of higher chlorophyll waters. These blooms are potentially driven by nitrogen fixation, or by vertically migrating phytoplankton, and a better understanding of their ubiquity could improve our estimate of the global nitrogen fixation rate. Here, global SeaWiFS chlorophyll data from 1997 to 2007 are examined to determine if similar blooms occur in other oligotrophic gyres. Our analysis revealed blooms in five other areas. Two of these are regions where blooms have been previously identified: the SW Pacific and off the southern tip of Madagascar. Previously, unnoticed summer blooms were also identified in the NE and SW Atlantic and in a band along 10°S in the Indian Ocean. There is considerable variation in the intensity and frequency of blooms in the different regions, occurring the least frequently in the Atlantic Ocean. The blooms that develop along 10°S in the Indian Ocean are unique in that they are clearly associated with a hydrographic feature, the 10°S thermocline ridge, which explains the bloom within a conventional upwelling scenario. The environment and timing of the blooms, developing in oligotrophic waters in late summer, are conducive to both nitrogen fixers and vertically migrating phytoplankton, which require a relatively stable water column. However, the specific locations of the chlorophyll blooms generally do not coincide with areas of maximum levels of nitrogen fixation or Trichodesmium. The NE Pacific chlorophyll blooms develop in a region with a very high SiO₄/NO₃ ratio, where silicate will not be a limiting nutrient for diatoms. The blooms often develop between eddies, wrapping around the periphery of anti-cyclonic features. However, none of the areas where the blooms develop have particularly high eddy kinetic energy, from either a basin-scale or a mesoscale perspective, suggesting that other factors, such as interactions with a front or dynamics associated with the critical latitude, operate in conjunction with the eddy field to produce the observed blooms.     

山东近岸海湾微型浮游植物分布及其丰度与营养盐相关性研究

2006年7月至2007年10月对山东近岸的威海湾、荣成湾、桑沟湾、靖海湾、五垒岛湾及乳山湾(37°28.7'-36°46.3'N,121°28.8'-122°39.6'E)的26个站位按季节进行了4个航次的现场调查,分析了6个海湾不同季节的微型藻类及营养盐情况,并进一步对几种主要微藻类群与各种营养盐之间的相关性进行了研究.结果表明,各海湾微型浮游植物的平均丰度在456.3×104-2332.2×104cell/L之间;夏季和春季的主要优势种为硅藻:冬季主要优势种为黄藻;秋季主要优势种为隐藻.不同微藻类群与不同营养盐的相关性差异显著,其中,与NH4-N的相关性依次为:绿藻＞黄藻＞隐藻＞甲藻＞硅藻＞金藻,相关系数依次分别为0.965、0.929、0.761、0.748、0.671和-0.304;与NO3-N的相关系数的绝对值为金藻＞隐藻＞甲藻＞硅藻＞黄藻＞绿藻;与PO4-P的相关系数的绝对值则为甲藻＞金藻＞绿藻＞黄藻＞隐藻＞硅藻.     

The effects of beach nourishment on the sandy-beach amphipod Exoediceros fossor: impact and recovery in Botany Bay, New South Wales, Australia

Beach nourishment is increasingly being implemented to address problems of erosion. However, the ecological consequences of nourishment are poorly understood, especially in Australia. In Botany Bay, sand was piped from an intertidal borrow area at Elephant's Trunk to nourish the nearby eroding beach at Towra Point. The effects on an intertidal exoedicerotid amphipod, Exoediceros fossor (Stimpson, 1856), were examined using a beyond-BACI (Before–After, Control–Impact) sampling design. Sampling was conducted before and after engineering operations at sites within the borrow and nourishment locations and multiple control locations. Hypotheses concerning impact and recovery were tested using asymmetrical ANOVAs and two-tailed F-tests. These examined the effects on abundance and spatial variability, respectively. The impact of the engineering operations on abundance was very large at both borrow and nourishment locations. However, recovery started within several weeks and, using space × time interactions as a criterion, appeared to be complete within a year. This conclusion is made cautiously because of low statistical power and because other criteria for recovery suggest that it was not complete at some sites. As beach erosion is likely to increase in severity with rising sea levels and greater storm surges associated with climate change, management authorities will need a better understanding of the ecological effects of beach nourishment.     

Assessing the extent of mangrove change caused by Cyclone Vance in the eastern Exmouth Gulf, northwestern Australia

Changes in mangal area were quantified in the eastern Exmouth Gulf over six years (1999–2004) after Cyclone Vance using Landsat TM satellite imagery and aerial photography. Vance was the strongest tropical cyclone ever to impact the Australian mainland before 2006 and produced wind gusts of more than 280 km h⁻¹. Image data were processed using ENVI™ and IDRISI™ software. Three sets of Landsat TM images from 1999 (a few days before the cyclone), 2002 and 2004 were used, along with 2004 digital aerial photography. A ‘common’ subset of 904 km² was selected from all images and classification was developed using ISODATA™ unsupervised classification to identify spectrally distinct areas followed by principal component analysis (PCA), vegetation indices and supervised classification. Some 12,800 ha of mangrove habitat was present before the cyclone and approximately 5700 ha (44%) was removed by it. Most mangroves lost (74%) between 1999 and 2004 were converted either to bare sediment or to live saltmarshes and this occurred mostly between 1999 and 2002. Five basic categories of damage were conspicuous from imagery and field observations, and evidence suggests that much of the loss was due to the longer term consequences of sediment deposition or smothering, rather than the immediate effects of wind or waves. Mangroves exhibited accelerated recovery between 2002 and 2004, and around 1580 ha regenerated during this time, amounting to a return of 68% of their former coverage. At this recovery rate we estimate that they should have returned to their pre-cyclone area by 2009. Over half of the saltmarsh habitats (54%) were removed by the cyclone (4060 ha) but their recovery has been far more rapid than mangroves. After 5 years, saltmarshes had returned to 87% of their previous area. The 5700 ha of mangrove habitat damaged by Cyclone Vance exceeds any anthropogenic impact that has ever taken place in Western Australia by several orders of magnitude.     

Climate change and coral reef bleaching: An ecological assessment of long-term impacts,recovery trends and future outlook

Since the early 1980s, episodes of coral reef bleaching and mortality, due primarily to climate-induced ocean warming, have occurred almost annually in one or more of the world's tropical or subtropical seas. Bleaching is episodic, with the most severe events typically accompanying coupled ocean–atmosphere phenomena, such as the El Niño-Southern Oscillation (ENSO), which result in sustained regional elevations of ocean temperature. Using this extended dataset (25+ years), we review the short- and long-term ecological impacts of coral bleaching on reef ecosystems, and quantitatively synthesize recovery data worldwide. Bleaching episodes have resulted in catastrophic loss of coral cover in some locations, and have changed coral community structure in many others, with a potentially critical influence on the maintenance of biodiversity in the marine tropics. Bleaching has also set the stage for other declines in reef health, such as increases in coral diseases, the breakdown of reef framework by bioeroders, and the loss of critical habitat for associated reef fishes and other biota. Secondary ecological effects, such as the concentration of predators on remnant surviving coral populations, have also accelerated the pace of decline in some areas. Although bleaching severity and recovery have been variable across all spatial scales, some reefs have experienced relatively rapid recovery from severe bleaching impacts. There has been a significant overall recovery of coral cover in the Indian Ocean, where many reefs were devastated by a single large bleaching event in 1998. In contrast, coral cover on western Atlantic reefs has generally continued to decline in response to multiple smaller bleaching events and a diverse set of chronic secondary stressors. No clear trends are apparent in the eastern Pacific, the central-southern-western Pacific or the Arabian Gulf, where some reefs are recovering and others are not. The majority of survivors and new recruits on regenerating and recovering coral reefs have originated from broadcast spawning taxa with a potential for asexual growth, relatively long distance dispersal, successful settlement, rapid growth and a capacity for framework construction. Whether or not affected reefs can continue to function as before will depend on: (1) how much coral cover is lost, and which species are locally extirpated; (2) the ability of remnant and recovering coral communities to adapt or acclimatize to higher temperatures and other climatic factors such as reductions in aragonite saturation state; (3) the changing balance between reef accumulation and bioerosion; and (4) our ability to maintain ecosystem resilience by restoring healthy levels of herbivory, macroalgal cover, and coral recruitment. Bleaching disturbances are likely to become a chronic stress in many reef areas in the coming decades, and coral communities, if they cannot recover quickly enough, are likely to be reduced to their most hardy or adaptable constituents. Some degraded reefs may already be approaching this ecological asymptote, although to date there have not been any global extinctions of individual coral species as a result of bleaching events. Since human populations inhabiting tropical coastal areas derive great value from coral reefs, the degradation of these ecosystems as a result of coral bleaching and its associated impacts is of considerable societal, as well as biological concern. Coral reef conservation strategies now recognize climate change as a principal threat, and are engaged in efforts to allocate conservation activity according to geographic-, taxonomic-, and habitat-specific priorities to maximize coral reef survival. Efforts to forecast and monitor bleaching, involving both remote sensed observations and coupled ocean–atmosphere climate models, are also underway. In addition to these efforts, attempts to minimize and mitigate bleaching impacts on reefs are immediately required. If significant reductions in greenhouse gas emissions can be achieved within the next two to three decades, maximizing coral survivorship during this time may be critical to ensuring healthy reefs can recover in the long term.     

正理庄高89-1区块CO2混相驱参数优化数值模拟研究

为了确保高89-1区块CO2混相驱项目的顺利实施,依据该区块的精细油藏描述成果,在优化适于CO2混相驱模型基础上,建立了符合油藏地质特点的三维地质模型。在此基础上对开发指标进行计算,对五个参数（井网、开发方式、压力水平、注入量和采油速度）进行优化,并提出了推荐方案,预测采收率可达23.10%,比弹性开采方式提高15.16%。     

提高机采水平的配套技术及应用

随着濮城油田的持续性高速开发,油田综合含水逐渐上升,油水井井况进一步恶化,作为油田生产主体的机械采油井躺井频繁、管杆泵使用寿命缩短。近几年中原油田采油二厂濮城油田年平均躺井数达560井次之多,导致机械采油井维护费用增加,管杆泵投入增大,严重制约着油田的生产和经营。通过加缓蚀剂在油管内壁形成保护油膜,起到润滑作用;应用特殊抽油杆防腐止磨;应用尼龙扶正器对抽油杆体扶正,避免了钢体与钢体的硬磨;应用旋转井口通过地面人力转动改变油管与抽油杆的偏磨面;配合合理生产参数;各种配套技术的合理应用,使濮城油田躺井减少,避免了频繁作业,增加长寿井,管杆泵投入节约了19.3%。