Satellite-Based Assessment of the Extent and Changes in the Mangrove Ecosystem of the Niger Delta

This study was carried out with the primary aim of understanding how the mangrove ecosystem in the Niger Delta has been altered recently. Specifically, we determined the spatial extent of the mangrove forest in the Niger Delta using remotely sensed satellite data and estimated changes in the spatial extent of the forest from the mid-1980s through 2003. Overall, about 21,340 hectares of Mangrove forest was lost over the study period. Fieldwork confirmed that these losses were primarily due to urbanization, dredging activities, activities of the oil and gas industries, and the spread of Nypa Palm (Nypa frutican) plant species.     

海洋地质灾害研究的几个基本问题

海洋地质灾害的发生，发展和分布有其自身的规律和特点，成因的复杂性，发生的周期性，多发和复发性，群发与同步性构成了共同的属性。依据致灾的动力条件大致可分为内动力地质条件，外动力地质条件和人为地质条件三种类型我国在灾种的调查研究，防灾和减灾对策上取得了显著的成效。     

海洋生态系统服务的分类与计量

通过界定海洋生态系统服务的概念和内涵以及分析其组成结构、生态过程及生物多样性等服务的来源,详细描述了海洋生态系统所提供的食品供给、原材料供给、基因资源、气候调节、空气质量调节、水质净化调节、有害生物与疾病的生物调节与控制、干扰调节、精神文化服务、知识扩展服务、旅游娱乐服务、初级生产、物质循环、生物多样性和提供生境等15项服务。根据这些服务的相似作用与性质,参照千年生态系统评估的分类体系,进一步归纳为供给服务、调节服务、文化服务以及支持服务这4大基本服务类型。同时,也对各项服务的内容、表现特征和计量特征进行了描述。海洋生态系统服务不仅是海洋管理的核心内容,提高和维持海洋生态系统服务更是海洋管理的最终目标。     

数据融合技术在多源潮汐数据分析中的应用

为了充分利用现有潮汐数据以建立高精度的潮汐分析模型，在利用最小二乘法进行潮汐分析的基础上，将数据融合技术应用于具有多源潮汐数据的分析，提出潮汐数据的分类方法，建立了三种潮汐数据融合方案，推导了各种方案的数据融合公式，并分析了各种方案的特点及适用范围。     

An attenuation-based sediment classification technique using Chirp sub-bottom profiler data and laboratory acoustic analysis

A remote sediment classification technique based on attenuation measurements from Chirp sub-bottom profiler data is described. This differs from previously published work in that attenuation measurements are obtained for each stratigraphic unit within a complex, thinly interbedded sedimentary sequence. Compressional wave attenuation measurements are obtained for a wide variety of lithologies, including muds, silts, sands, clayey sands, silty clays and gravel lags, with grain sizes ranging from 8 Phi to -4 Phi. In addition, attenuation measurements from sub-bottom profiler data were calibrated against laboratory acoustic measurements of vibracores and seabed samples from corresponding geographic locations, under simulated in-situ conditions using a Pulse Tube method. We adapt an instantaneous frequency matching method using a causal attenuation filter to model the decay of the Chirp transmitted waveform. From this modelling, a relationship between t* (a causal attenuation operator) and change in instantaneous frequency is established. The Hilbert transform is used to extract instantaneous frequency information from Chirp seismic, which is used to derive attenuation information for selected individual stratigraphic layers imaged by the sub-bottom profiler. This paper draws attention to the limitations in comparing attenuation measurements derived from Chirp sub-bottom profiler data against previously published literature on experimental attenuation measurements, which are limited by the wide variance of these data, and the difficulty in finding a meaningful best fit to these data. This demonstrates the importance of calibrating remote sediment classification observations using complimentary acoustic analysis of seabed samples to generate a site-specific geoacoustic database. A positive correlation between laboratory and sub-bottom profiler attenuation measurements was obtained, with a correlation coefficient of 0.885. Poorly sorted gravels with a mixed lithic and biogenic pebble component are characterised by very high attenuation with values of Q from 4 to 19. These sediments are considerably coarser-grained than those typically described in previously published experimental studies.     

变性水团软划分的一种FUZZY模式

在已知研究海区水团核心的前提下,考虑到各种指标对标识水团的不同贡献,提出了一种水团软划分的FUZZY模式。利用1987年5—6月黄东海的温、盐和溶解氧实测资料进行计算,与已有成果作了对比,结果令人满意。     

海洋心血管药物及活性物质的研究现状与展望

按照海洋心血管活性成分的化学分类，本文较系统地列举了该领域中的研究成果和动态，对有代表意义的重点药物作较详细的评述，并探讨了有关海洋心血管药物研究工作的特点及发展前景。     

闽江口的盐、淡水混合

采用盐、淡水混合比的概念研究闽江口的混合状态，并确定了分层、部分混合、高度混合３种类型的分类指标。研究表明，闽江口主要水道的盐、淡水混合以部分混合为主，其次是分层，高度混合出现的机率较少；盐水异重流发育良好，混合状态的变化与潮流速的变化不相一致；盐水入侵时混合比相对较小，后退时相对较大。闽江口是一个径、潮量比值较小的强潮河口，按照一般规律，其盐、淡水混合应该出现高度混合型，但在闽江口的主汊道中发生     

海岛遥感图像数据管理示范系统的构架与分析

使用数据分割和数据开采技术将海岛遥感图像数据分割成较小的可以独立管理的物理单位,然后对其图像数据进行重构和重组以及非监督分类、截取、拼接和波形比对.此数据管理系统除具有访问常规的数据库管理、维护和使用等功能外,还根据应用需求,在集成系统环境下开发了处理后光谱数据的特征量分析、推理和判断功能.