应用MODIS影像监测海州湾无机氮浓度的研究

利用连云港海州湾2004年至2006年的水质监测资料,选取时间上完全同步的空间分辨率为500m的MODIS Terra 1B数据,对反射率的单波段因子和波段组合因子与可溶无机氮（DIN）质量浓度之间进行相关分析。从总体上看,单波段因子与DIN质量浓度的相关性较低,但在含氮基团倍频和合频吸收带附近的波段（波段2、7）反射率与DIN质量浓度呈负相关,显示了含氮基团对水体光谱特征的影响;在波段组合因子中,因子F11（3.4）和F13（3.4）与DIN质量浓度呈显著正相关,用这两个因子建立DIN质量浓度的回归模型,R^2都达到0．7以上,相对精度达70％左右,最终选择因子F11（3.4）的线性模型反演该海域的DIN质量浓度,其结果与实际情况非常吻合。     

A predictive numerical model for potential mapping of the gas hydrate stability zone in the Gulf of Cadiz

This paper presents a computational model for mapping the regional 3D distribution in which seafloor gas hydrates would be stable, that is carried out in a Geographical Information System (GIS) environment. The construction of the model is comprised of three primary steps, namely: (1) the construction of surfaces for the various variables based on available 3D data (seafloor temperature, geothermal gradient and depth-pressure); (2) the calculation of the gas function equilibrium functions for the various hydrocarbon compositions reported from hydrate and sediment samples; and (3) the calculation of the thickness of the hydrate stability zone. The solution is based on a transcendental function, which is solved iteratively in a GIS environment.The model has been applied in the northernmost continental slope of the Gulf of Cadiz, an area where an abundant supply for hydrate formation, such as extensive hydrocarbon seeps, diapirs and fault structures, is combined with deep undercurrents and a complex seafloor morphology. In the Gulf of Cadiz, the model depicts the distribution of the base of the gas hydrate stability zone for both biogenic and thermogenic gas compositions, and explains the geometry and distribution of geological structures derived from gas venting in the Tasyo Field (Gulf of Cadiz) and the generation of BSR levels on the upper continental slope.     

Palynology and petroleum potential of the Kazhdumi Formation (Cretaceous: Albian–Cenomanian) in the South Pars field,northern Persian Gulf

The Kazhdumi Formation of the Bangestan Group is a well-known source rock that has produced abundant oil in most petroleum fields in the Zagros Basin, which stretches from northwest to southwest Iran over hundreds of kilometres. The formation reaches a thickness of 230 m at the type section in northwest Zagros but thins out to 40–50 m in wells studied from the South Pars giant petroleum field, where it comprises mainly grey shales with occasional intercalations of marls and sandstones. South Pars, best known as the Iranian part of the world's largest non-associated gas field, contains small quantities of oil above and below the Kazhdumi Formation.     

Impacts of trawling on benthic macro-fauna and -flora of the Spencer Gulf prawn fishing grounds

The overall effects of trawling on benthic habitats and their assemblages are dependent on the distribution and intensity of trawl effort. The benthic habitats of the Spencer Gulf prawn trawling grounds are subjected to known variable levels of trawling disturbance recorded from fisher's logbooks. These habitats have not been quantitatively investigated. The aim of the study was firstly to characterise the macro-faunal and -floral assemblages and secondly, to comparatively assess trawl impact by testing the null hypothesis of no differences between five sites exposed to different intensity of trawl effort. The distribution and abundance of benthic macro-fauna and -flora were studied at two sampling resolutions by using beam trawl sampling (10,000 m²) and underwater stereophotography (4.5 m²) at five sites with different levels of trawl disturbance (effort). The results showed that the Spencer Gulf prawn trawling grounds are characterised by sandy sediments with a low content of silt and clay, with the exception of one site with very fine gravel. Biomass, abundance and cover of macro-fauna and -flora were generally low throughout, but with large differences among sites. Biomass, abundance and cover were found to be negatively correlated to both trawl hours from 1994–1998 and during the period of study. ANOSIM and SIMPER analyses using biomass, abundance and percentage cover as variables showed significant differences between sites with eight species or taxonomic groups contributing more than 10% to the observed similarity within sites. The two northern sites were dominated by sponges and the bearded mussel, Trichomya hirsutus, and the southern hammer oyster, Malleus meridianus. Other species that contributed to the similarity within sites were the ascidian, Polycarpa viridis, mobile epifauna (the blue swimmer crab, Portunus pelagicus, and the western king prawn, Penaeus (Melicertus) latisulcatus) and demersal fish species (Degens leatherjacket, Thamnaconus degeni, and the Melbourne silver belly, Parequula melbournensis). Simpson's Index of Diversity (1 − λ) and species richness in the beam trawl samples were fairly even across all sites, but a significant effect of site was found in the stereophotographic transect samples. It was concluded that prawn trawling has a strong influence on the structure of the benthic habitats of the Spencer Gulf prawn fishing grounds highlighted by the magnitude of change and the strength of the gradient of effects. Confounding factors linked to the biophysical attributes of the sites are believed to be minor.     

Distribution of ciliates in relation to environmental factors along the coastline of the Gulf of Gabes, Tunisia

We studied the seasonal distribution of the ciliate community coupled with environmental factors along the coast at three stations sampled (from March 2006 to February 2007) in the Gulf of Gabes (Tunisia, Eastern Mediterranean Sea). A total of 56 species belonging to 11 orders, were identified. Harbor of Gabes station was more diversified (45 species) than both Tabia (26 species) and Karboub (31 species) stations. The ciliate assemblage was numerically dominated by Spirotrichea in Tabia (82% of the total abundance), in the Harbor of Gabes (86% of the total abundance), whereas, in Karboub, Spirotrichea represented only 40% of the total abundance. The unexpected lower quantitative importance of Spirotrichea in Karboub station was apparently the result of the high salt concentration found in water samples throughout the study, probably originating from the saline area surrounding Karboub station, known as Sabkha. The distribution of species in the nearshore of the Gulf of Gabes seemed most likely influenced by the combined effects of temperature, salinity and hydrographic conditions.     

Sensitivity of hurricane surge to morphological parameters of coastal wetlands

Given the history and future risk of storm surge in the United States, functional storm protection techniques are needed to protect vital sectors of the economy and coastal communities. It is widely hypothesized that coastal wetlands offer protection from storm surge and wave action, though the extent of this protection is unknown due to the complexities of flow through vegetation. Here we present the sensitivity of storm-surge numerical modeling results to various coastal wetlands characteristics. An idealized grid domain and 400-km² marsh feature were used to evaluate the effects of marsh characteristics on hurricane surge, including the effects of bottom friction, elevation, and continuity (the ratio of healthy marsh to open water area within the total wetland area).Through coupled hydrodynamic and wave model simulations, it is confirmed that increased bottom friction reduces storm-surge levels for most storms. However, increases in depth associated with marsh elevation loss generally results in a reduction of surge. As marsh continuity is decreased, coastal surge increases as a result of enhanced surge conveyance into and out of the marsh. Storm surge is parameterized in terms of marsh morphology, namely marsh elevation, frictional characteristics, and degree of segmentation, which will assist in the justification for and optimization of marsh restoration in terms of storm protection.     

Scleractinian cold-water corals in the Gulf of Cádiz—First clues about their spatial and temporal distribution

This paper presents the first compilation of information on the spatial distribution of scleractinian cold-water corals in the Gulf of Cádiz based on literature research and own observations (video footage, sediment samples). Scleractinian cold-water corals are widely distributed along the Spanish and Moroccan margins in the Gulf of Cádiz, where they are mainly associated with mud volcanoes, diapiric ridges, steep fault escarpments, and coral mounds. Dendrophyllia cornigera, Dendrophyllia alternata, Eguchipsammia cornucopia, Madrepora oculata and Lophelia pertusa are the most abundant reef-forming species. Today, they are almost solely present as isolated patches of fossil coral and coral rubble. The absence of living scleractinian corals is likely related to a reduced food supply caused by low productivity and diminished tidal effects. In contrast, during the past 48 kyr scleractinian corals were abundant in the Gulf of Cádiz, although their occurrence demonstrates no relationship with main climatic or oceanographic changes. Nevertheless, there exists a conspicuous relationship when the main species are considered separately. Dendrophylliids are associated with periods of relatively stable and warm conditions. The occurrence of L. pertusa mainly clusters within the last glacial when bottom current strength in the Gulf of Cádiz was enhanced and long-term stable conditions existed in terms of temperature. Madrepora oculata shows a higher tolerance to abrupt environmental changes.     

墨西哥湾天然气水合物矿产资源预测模型及其应用

墨西哥湾是世界上研究天然气水合物较深入的海区,调查资料丰富,已在50多处采集到天然气水合物样品,具备建立天然气水合物矿产资源预测模型的条件。选择34处已知天然气水合物矿点和34处已知无矿点作为训练区,建立矿点存在与否的预测模型。模型的相关系数值表明墨西哥湾天然气水合物与盐底辟关系密切。将该模型应用于整个墨西哥湾北部,初步获得了天然气水合物存在可能性概率分布图;概率大于0.7的预测单元包含已知矿点中的30个,利用该阈值圈定了墨西哥湾天然气水合物潜在资源分布区。     

北部湾地形、底质特征与渔场分布的关系

北部湾作为南海北部重要水域.属于热带和亚热带半封闭海湾.湾内地形地貌以及底质特征复杂。鱼类资源丰富。北部湾渔区的划分与地形地貌、底质特征存在密切联系.为更好的了解渔业生物的生活史、空间配布以及北部湾的渔业资源特点本文进行了初步的基础研究。为北部湾的渔业资源开发提供了科学依据。