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hydrography and Circulation in the Eastern Tropical Indian Ocean during April-May 2011

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Atmospheric and Oceanic Science Letters 2012年第4期5卷 284-289页

作者： XUAN Li-Li QIU Yun XU Jin-Dian HE Yun-Kai Third Institute of Oceanography State Oceanic Administration Xiamen 361005 China State Key Laboratory of Tropical Oceanography South China Sea Institute of Oceanology The Chinese Academy of SciencesGuangzhou 510301 China

The distribution of hydrography and circulation in the eastern tropical Indian Ocean(ETIO) during April-May 2011 were analyzed using cruise observations,satellite observations,and historic hydrographic *** was observed that warm water(>28℃) occupies the upper 50-m layer in the ***-salinity surface water was observed at the mouth of the Bay of Bengal(BOB),which further extends to the Arabian Sea and off Sumatra via the Sri Lanka coast and the eastern bay *** Sea high-salinity water(ASHSW) is carried eastward along the equator to around 90°E by the equatorial undercurrent(EUC).It also runs south of Sri Lanka(north to 3°N) and in the western bay mouth(west to 87°E) but is much shallower than its counterpart at the *** is suggested to be the residual of the ASHSW,which intrudes into the BOB during the preceding southwest *** results also show that,in the south of Sri Lanka,just below this subsurface high-salinity water,very-low-salinity water(about 34.8) occurs at depths of 100-200 *** analysis suggests that this low-salinity water comes from the BOB.

关键词： eastern tropical Indian Ocean hydrography circulation

Review of near-shore satellite derived bathymetry: Classification and account of five decades of coastal bathymetry research

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Journal of Ocean Engineering and Science 2021年第4期6卷 340-359页

作者： Mohammad Ashphaq Pankaj K Srivastava D Mitra National Hydrographic Office DehradunIndia University of Petroleum&Energy Studies(UPES) DehradunIndia Indian Institute of Remote Sensing DehradunIndia

The number of civilian,commercial and military applications are dependant on accurate knowledge of bathymetry of coastal ***,hydrographic surveying methods are used for bathymetric surveys carried by ship-based acoustic systems,but needs highcost *** technology has provided a cost-effective alternate means for charting near shore and inaccessible *** optical satellite data have capabilities to offer alternate solution in near-shore region,which has been researched for past 50 years,using evolving algorithms to estimate Satellite Derived Bathymetry(SDB).However,there is no agreement on use of terms like approach,model,method and techniques,which have been used varyingly and interchangeably as per context of SDB *** paper suggests a classification scheme for SDB algorithms which is also applicable to other Marine Remote Sensing *** this paper,based on literature available on SDB for the past five decades,an insight on SDB classification has been offered grounded in research *** SDB approaches,models,methods and techniques have been elaborated with chronological development,along with SDB studies based on them,their accuracy and errors in SDB *** have suggested a matrix of prerequisite satellite data,in-situ data resolution,methods and algorithms of SDB based on level of accuracy needs to be achieved,which will guide future researchers to select one as per their context of research.

关键词： Satellite derived bathymetry hydrography Bio-optical model Physio-optical model

The Influence of Large-Scale Phenomena on La Paz Bay Hydrographic Variability

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Open Journal of Marine Science 2015年第1期5卷 146-157页

作者： Cristóbal Guevara-Guillén Bernardo Shirasago-Germán Edgar Leonardo Pérez-Lezama Centro Interdisciplinario de Ciencias Marinas (CICIMAR-IPN) Colonia Playa Palo de Santa RitaLa Paz México

We analyzed the hydrographic variability of La Paz Bay, the largest coastal water body in the Gulf of California, and its relationship with Pacific large-scale phenomena, including the El Ni?o-Southern Oscillation (ENSO), Pacific Decadal Oscillation (PDO), Pacific-North America pattern (PNA), and North Pacific pattern (NP). We used several indices related to these phenomena and the hydrographic variability data of La Paz Bay, consisting of the annual sea surface temperature patterns from satellite imagery from 2000 to 2010 and the mixed layer depths measured with?in situ?data from 1994 to 2009. The results indicate the sea surface temperature fluctuated during the study period, with 2007 as the coldest year and 2009 as the warmest. Two periods were identified in the annual thermal cycle of the bay, one period of warmth from June to November, and one of cold from December to May. The sea surface temperature is primarily influenced by the ENSO. The mixed layer depth analysis showed its absence during August-September, while the deepest ones were in November-March. The unusual 100 m mixed layer depth noted during February 2002 and its absence in March 1996 and 2009 were related to uncommon atmospheric conditions in the annual patterns of the ENSO, PNA, and NP. The variability of the mixed layer depth is primarily related to the variability of the NP. We concluded that the hydrographic conditions of La Paz Bay are most influenced by the NP during the cold phase of its annual cycle, and by the ENSO during the warm phase.

关键词： Pacific Large-Scale Phenomena La Paz Bay Gulf of California hydrography Annual Patterns

Assessment of the Hydrochemical Characteristics of the Suez Gulf Coastal Waters during 2011-2013

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Journal of Environmental Protection 2016年第11期7卷 1497-1521页

作者： Ehssan M. Abo-El-Khair Laila M. Abdel Fattah Ahamed M. Abdel-Halim Mohamed A. Abd-Elnaby Mamdouh A. Fahmy Hoda H. Ahdy Ahamed Hemeilly Ahamed Abu El-Soud Mohamed A. Shreadah Environmental Affairs Agency Ministry of Environmental Affairs Cairo Egypt National Institute of Oceanography and Fisheries Alexandria Egypt Environmental Affairs Agency Ministry of Environmental Affairs Cairo Egypt

The coastal region of the Suez Gulf, is one of the most densely industrialized zones in Egypt. In order to assess the quality of Suez Gulf coastal waters for the sustainable use and development, and consequently for the national income, 12 field campaigns were carried out in 3 years (2011-2013). The results of beach litter cleared out that the shoreline of the Suez Gulf, especially Ras Gharib area was subjected to many factors which undoubtedly affected the rate of man-made litter accumulation. The most abundant visible items were general litter as they represented 30.64% of the total items encountered. Oil, seaweeds as well as old and new tar constituted 15.41%, 14.85% and 11.84%, respectively. The increase on the levels of water temperature, Chl-a, TSM, DO, BOD, DOM, COD, ammonium ion, nitrite, nitrate, total phosphorus, silicate and total nitrogen developed a eutrophic region. In general, dissolved inorganic nitrogen (DIN) species were almost 9 times higher in the northern parts compared to the south-ern ones revealing that the northern parts of the Gulf were more affected by human impacts compared to the southern area. Moreover, concentrations of most studied metals such as Zn, Mn, Ni, Cu, Cr, Cd, Pb, and Hg were higher in Northern parts com-pared to southern parts of the Gulf. The concentrations of dissolved metals in the northern and southern Suez Gulf followed the following order: Fe ≥ Zn ≥ Cu > Pb > Mn > Ni > Cr > Cd ≥ Hg. Except for Hg, concentrations of metals were in the accepta-ble ranges recommended internationally. Hg concentrations especially in the northern Suez Gulf were slightly higher than the permissible levels. As the northern parts of the Gulf were more suffered from oil pollution, total petroleum hydrocarbons revealed higher concentrations in the northern parts compared to the southern parts of the Gulf. Seasonal variations, on the other hand, indicated higher levels of DO, BOD, DOM and COD, chloropyll-a, TSM, ammonia, nitrate, total nitrogen

关键词： hydrography Nutrient Salts Heavy Metals Petroleum Hydrocarbons Coastal Water Suez Gulf

The Conceptual Model and Its Empirical Studies of Sustainable Carrying Capacity of Water Resources: A Case Study of China Mainland

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Journal of Resources and Ecology 2019年第1期10卷 9-20页

作者： ZANG Zheng School of Urban and Environmental Sciences Huaiyin Normal UniversityHuai’anJiangsu 223300China The Research Institute of Huaihe River Watershed Ecological Economy Belt Huai’anJiangsu 223300China

Based on the interactive development of new industrialization, rapid urbanization and agricultural modernization(IUAM), and from the viewpoint of interactive responses and supply-demand relationships between regional water resources carrying capacity and economic-social development, this paper puts forward the concepts and characterization methods of water resources relative intensity(WRI), water resources carrying rate(WCR) and sustainable index of water resources system(WSI). Considering the catastrophic trait of water resources carrying capacity and its contradictory relationship with WRI, a modified Catastrophe Model, which combines Catastrophe Theory and Fuzzy Mathematic Theory, was introduced to perform a multi-objective and multi-criterion comprehensive assessment of the sustainability of water resources carrying capacity(WSCC) based on benchmarking. According to these concepts and models, land WSCC for the China mainland was set as an example for empirical analysis. The results showed that at the scale of first-grade water regions, Liaohe River, Yangtze River and Pearl River regions had high WRI of domestic water, while Northwestern Rivers, Southeastern Rivers regions and Yangtze River region in some years had high WRI of eco-environment water. However, they were all in a downtrend, while the other four northern regions had low WRI in an uptrend. The agricultural WRI in Songhua River, Yellow River and Northwestern Rivers regions were relatively high and industrial WRI in Songhua River, Yangtze River and Pearl River regions were also relatively high. At the provincial scale, WSCC of urban domestic water was relatively stable, WSCC of eco-environment was obviously fluctuating, and WSCC of agriculture and industry were constantly rising. Overall, WRI in the China mainland generally decreased. The convergence of provinces with high consumption intensity of water resources and spatial spillover of WUE in high WCR provinces promotes water resources development and

关键词： hydrography multi-objective optimization sustainability supply-demand relationship China mainland

Invasion of Danish and Adjacent Waters by the Comb Jelly Mnemiopsis leidyi—10 Years After

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Open Journal of Marine Science 2017年第4期7卷 458-471页

作者： Hans Ulrik Riisgard Marine Biological Research Centre(University of Southern Denmark) KertemindeDenmark

The invasive ctenophore Mnemiopsis leidyi, which comes from North America’s east coast, was observed in Danish waters for the first time in 2007. Since then, the new invader has every summer spread in Danish and adjacent waters (i.e. North Sea, Limfjorden, Skagerrak, Kattegat, Belt Sea, Baltic Sea). The invasive comb jelly has apparently come to stay, as it has no effective enemies. Possible harmful effects of M. leidyi which feeds voraciously on zooplankton, fish eggs and larvae, have so far not been thoroughly studied in Danish waters, although dedicated attempts have been made in Limfjorden and in the central Baltic Sea. Over the last 10 years, the Danish national environmental monitoring program did not include gelatinous zooplankton, but new initiatives have been recently taken. A brief overview of our current knowledge on the impact of M. leidyi in Danish waters is given here.

关键词： Invasive Ctenophore Alien Comb Jelly Mnemiopsis leidyi Predation Impact Zooplankton Limfjorden Baltic Sea Kattegat Great Belt hydrography

Evaluation of the Quality for the Egyptian Red Sea Coastal Waters during 2011-2013

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Journal of Environmental Protection 2016年第12期7卷 1810-1834页

作者： Mamdouh A. Fahmy Laila M. Abdel Fattah Ahmed M. Abdel-Halim Mohamed A. Aly-Eldeen Ehssan M. Abo-El-Khair Hoda H. Ahdy Hoda H. Ahdy Ahmed Hemeilly Ahmed Abu El-Soud Mohamed A. Shreadah National Institute of Oceanography and Fisheries Alexandria Egypt Environmental Affairs Agency Ministry of Environmental Affairs Cairo Egypt

To assess the quality of the Egyptian Red Sea coastal waters for the sustainable use and development, due to its importance for the national income, four field campaigns were annually carried out during the period from 2011-2013 to investigate the hydrography, nutrient salts, heavy metals and petroleum hydrocarbons. Except for the area of Bir Shalatein, the results of beach litter cleared out that the shoreline of the studied area is not affected by man-made litter. No sewage could be observed. The results of the present study showed that water temperature followed seasonal changes in air temperature. Red Sea water is more saline than adjacent Arabian Sea. DO revealed high values and presence of well oxygenated waters. Minor changes in the distribution of pH, BOD, DOM and COD, revealed that limited effects of human impacts and depend mainly on the dynamics of its water as well as on the geographical location. Low Chl-a and TSM concentrations and high transparency revealed that also the effect of human impacts is almost negligible. Significantly higher sea water temperatures, TSM, pH, DO, BOD, DOM, and COD were observed in summer season compared to their corresponding values in winter season. Dissolved inorganic nitrogen concentrations were quite low because there is little nutrient input from soil, agriculture and pollution on land. Based on the annual mean values, the pattern concentrations of dissolved inorganic nitrogen forms followed the order: NO3 > NH4 > NO2. The Red Sea coastal waters are classified as oligotrophic to mesotrophic state. A remarkable increase of PO4 concentration was observed in the middle Red Sea stations due to huge amounts of effluents enriched with phosphate from the main shipping and industry of Phosphate Companies. SiO4 displayed a large variability due to the supply of SiO4, which flows in the Red Sea through the strait of Bab El-Mandab, biological consumption, organic ma

关键词： hydrography Nutrient Salts Heavy Metals Petroleum Hydrocarbons Coastal Water Red Sea

The Sediment and Hydrographic Characteristics of Three Horseshoe Crab Nursery Beaches in Hong Kong

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Journal of Ocean University of Qingdao 2003年第1期2卷 35-43页

作者： Helen M.C. Chiu Brian Morton Environmental Resources Management (ERM)-Hong Kong Ltd Swire Institute of Marine Science and Department of Ecology and Biodiversity 979 King's Road Taikoo Place Island East Hong Kong University of Hong

Horseshoe crab juveniles have been recorded from sand and sandy-mud nursery beaches at Pak Nai (western New Territories), San Tau and Shui Hau (Lantau Island), Hong Kong. In order to provide a better understanding of these beaches and to identify those plausible factors which have made them preferred by spawning horseshoe crabs, environmental parameters, including temperature, salinity, pH and dissolved oxygen content of the water, and particle size distribution and organic matter content of the sediments at the three sites, were determined and compared. The hydrographic and sediment data obtained for the three study sites have revealed some common environmental features. The three nursery beaches are relatively remote, and far (in Hong Kong terms) from urbanized and densely populated areas. The beaches are generally well sheltered from strong wave action and inundated regularly by estuarine waters. Horseshoe crab adults tend to select these beaches for spawning as their protected features ensures the laid eggs are less likely to be washed out of the sand, and hatched juveniles can feed on the meiofauna and grow. Sediments of the three beaches largely comprise medium-sized sand particles and are moderately sorted, suggesting medium porosity and good water permeability. Such a sand type, with the generally high oxygen levels in incursing waters, may help create a well-oxygenated micro-environment for the normal development of horseshoe crab eggs, larvae and juveniles. Lantau Island beaches at San Tau and Shui Hau are relatively free from organic pollution, as reflected in generally high dissolved oxygen level, and low BOD 5 and ammonia nitrogen values. Pak Nai is, however, more polluted.

关键词： sediment hydrography horseshoe crab nursery beaches Hong Kong

Roles of Geospatial Technologies in Hydrographic Practice

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Journal of Marine Science 2022年第1期4卷 1-10页

作者： Okpuvwie Ejuvweyere Jonathan Garba Mustapha Department of Geographic Information Science African Regional Institute for Geospatial Information Science and Technology(AFRIGIST)Obafemi Awolowo University CampusIle-IfeNigeria

Any seafarer or mariner that uses the sea knows that navigation without correct charts is impossible and hazardous because nautical charts are the most essential and indispensable tools for vessels to sail safely at *** vessels to safely sail at sea,the seas and the oceans ought to be charted and this falls within the domain of ***,the seas cannot be charted effectively in the absence of the deployment of human resources and adequate tools like satellite and aerial imagery,survey boats and other equipment that will facilitate the hydrographic *** acquisition of data and information about the sea depths,nature of sea bed,waterways,navigational hazards and navigational objects among others,basically falls within the sphere of hydrography which is primarily known as survey at *** paper offers a review of geospatial technologies in hydrographic practice for enhanced safety of navigation at *** review is important to both the mariners,shipping industry and the government in order to explore the potentials provided by Geographic Information System,Remote Sensing,cloud GIS,big data GIS and Global Positioning System to enhance the practice of *** data and materials used for the review were obtained from literature in the internet and other published *** paper looked at hydrography as a profession,roles of geospatial technologies in hydrographic practice,benefits of hydrography to national development and finally,the weaknesses of geospatial technologies in hydrographic practice were equally examined.

关键词： Geospatial Geographic information system hydrography Navy Navigation Sea Vessels