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Plankton blooms in vortices: the role of biological and hydrodynamic timescales
M. Sandulescu, C. López, E. Hernández-García,U. Feudel
Nonlinear Processes in Geophysics (NPG) , 2007,
Abstract: We study the interplay of hydrodynamic mesoscale structures and the growth of plankton in the wake of an island, and its interaction with a coastal upwelling. Our focus is on a mechanism for the emergence of localized plankton blooms in vortices. Using a coupled system of a kinematic flow mimicking the mesoscale structures behind the island and a simple three component model for the marine ecosystem, we show that the long residence times of nutrients and plankton in the vicinity of the island and the confinement of plankton within vortices are key factors for the appearance of localized plankton blooms.
Advance in Remote Sensing of Petroleum Resources
油气资源遥感研究进展

WEI,Junchao,
魏俊超

遥感技术与应用 , 1997,
Abstract: The conception,content,historical development and present situation of the remote sensing of petroleum resources were explained,and the developmental trends and application prospects of this newly emerging discipline were submitted in this paper.A new sensor:Advanced Spaceborne Thermal Emission Reflection Radiometer (ASTER) carried on EOS AM 1 which will be launched in 1998 was introduced,and the basic principles of remote sensing detecting petroleum were also proposed by the author.
Biologging, Remotely-Sensed Oceanography and the Continuous Plankton Recorder Reveal the Environmental Determinants of a Seabird Wintering Hotspot  [PDF]
Jér?me Fort, Grégory Beaugrand, David Grémillet, Richard A. Phillips
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0041194
Abstract: Marine environments are greatly affected by climate change, and understanding how this perturbation affects marine vertebrates is a major issue. In this context, it is essential to identify the environmental drivers of animal distribution. Here, we focused on the little auk (Alle alle), one of the world’s most numerous seabirds and a major component in Arctic food webs. Using a multidisciplinary approach, we show how little auks adopt specific migratory strategies and balance environmental constraints to optimize their energy budgets. Miniature electronic loggers indicate that after breeding, birds from East Greenland migrate >2000 km to overwinter in a restricted area off Newfoundland. Synoptic data available from the Continuous Plankton Recorder (CPR) indicate that this region harbours some of the highest densities of the copepod Calanus finmarchicus found in the North Atlantic during winter. Examination of large-scale climatic and oceanographic data suggests that little auks favour patches of high copepod abundance in areas where air temperature ranges from 0°C to 5°C. These results greatly advance our understanding of animal responses to extreme environmental constraints, and highlight that information on habitat preference is key to identifying critical areas for marine conservation.
Plankton blooms in vortices: The role of biological and hydrodynamic time scales  [PDF]
M. Sandulescu,C. Lopez,E. Hernandez-Garcia,U. Feudel
Physics , 2008,
Abstract: We study the interplay of hydrodynamic mesoscale structures and the growth of plankton in the wake of an island, and its interaction with a coastal upwelling. Our focus is on a mechanism for the emergence of localized plankton blooms in vortices. Using a coupled system of a kinematic flow mimicking the mesoscale structures behind the island and a simple three component model for the marine ecosystem, we show that the long residence times of nutrients and plankton in the vicinity of the island and the confinement of plankton within vortices are key factors for the appearance of localized plankton blooms
Bioprospecting Marine Plankton  [PDF]
Heni Abida,Sandrine Ruchaud,Laurent Rios,Anne Humeau,Ian Probert,Colomban De Vargas,Stéphane Bach,Chris Bowler
Marine Drugs , 2013, DOI: 10.3390/md11114594
Abstract: The ocean dominates the surface of our planet and plays a major role in regulating the biosphere. For example, the microscopic photosynthetic organisms living within provide 50% of the oxygen we breathe, and much of our food and mineral resources are extracted from the ocean. In a time of ecological crisis and major changes in our society, it is essential to turn our attention towards the sea to find additional solutions for a sustainable future. Remarkably, while we are overexploiting many marine resources, particularly the fisheries, the planktonic compartment composed of zooplankton, phytoplankton, bacteria and viruses, represents 95% of marine biomass and yet the extent of its diversity remains largely unknown and underexploited. Consequently, the potential of plankton as a bioresource for humanity is largely untapped. Due to their diverse evolutionary backgrounds, planktonic organisms offer immense opportunities: new resources for medicine, cosmetics and food, renewable energy, and long-term solutions to mitigate climate change. Research programs aiming to exploit culture collections of marine micro-organisms as well as to prospect the huge resources of marine planktonic biodiversity in the oceans are now underway, and several bioactive extracts and purified compounds have already been identified. This review will survey and assess the current state-of-the-art and will propose methodologies to better exploit the potential of marine plankton for drug discovery and for dermocosmetics.
Ecological Effect of No.0 Diesel Water Accommodated Fraction on Marine Algae
No.0柴油水溶组分海洋浮游植物生态效应研究

LI Ke-qiang,WANG Xiu-lin,ZHU Chen-jian,SHI Xiao-yong,HU Hai-yan,LI Rui-xiang,SUN Sheng-yu,
李克强
,王修林,祝陈坚,石晓勇,胡海燕,李瑞香,孙胜玉

环境科学 , 2007,
Abstract: With batch culture experiments in field and laboratory, the ecological effect of No.0 diesel water accommodated fraction on marine algae was studied. A growth model of marine algae under grazing pressure and a model of growth effect on marine algae with different doses No.0 diesel water accommodated fraction were proposed. Based on the model and experiments, the growth effect of No.0 diesel water accommodated fraction on marine algae was studied. The results show that, the growth model of marine algae under grazing pressure is more suited for the marine ecological system than Logistic model. And the final biomass (Bf) of marine algae with different doses No.0 diesel water accommodated fraction was calculated by the model with none-linear fitting software. The results also show that, under the field and laboratory conditions, lower doses No.0 diesel water accommodated fraction promotes the growth of marine algae, and the most promoting ratio are 180% and 120% respectively, however, higher doses hardly promotes but bates the growth of marine algae.
ADVANCE OF EXPLORATION AND PETROLEUM GEOLOGICAL FEATURES OF DEEP-WATER HYDROCARBON IN THE WORLD
世界深水油气勘探进展与我国南海深水油气前景

WU Shi-guo,YUAN Sheng-qiang,
吴时国[]
,袁圣强[,]

天然气地球科学 , 2005,
Abstract: Exploration in deepwater hydrocarbon has a fast increase in the world.The water depth for drilling well arrived to 3 050 m in 2004.Three giant China oil companies(CNPC,CNOOC,SINOPEC) launch the oil exploration in the deep water region of the South China Sea(SCS).According to the discoveries in the world,all of them are distributed in the passive continental margin.Three giant sedimentary sequences have been deposited in the basin,those are prorifting,rifting and breakup sedimentary sequences.Source rocks are lacustrine and shore facies,as well as afterrifting drift marine limestone and shale.The reservoirs are characterized by the deepwater turbidite sandstones,and rifting sandstone.The hydrocarbon reservoirs preserved in the various trap in the rifting basin,and some unique deepwater turbidite sandstone,and diapir structures.By the geological analysis of the two deep water regions in the SCS,the same petroleum geological features and richful hydrocarbon exist in the SCS.
Metagenome-based analysis: A promising direction for plankton ecological studies
QingYun Yan,YuHe Yu
Science China Life Sciences , 2011, DOI: 10.1007/s11427-010-4103-4
Abstract: The plankton community plays an especially important role in the functioning of aquatic ecosystems and also in biogeochemical cycles. Since the beginning of marine research expeditions in the 1870s, an enormous number of planktonic organisms have been described and studied. Plankton investigation has become one of the most important areas of aquatic ecological study, as well as a crucial component of aquatic environmental evaluation. Nonetheless, traditional investigations have mainly focused on morphospecies composition, abundances and dynamics, which primarily depend on morphological identification and counting under microscopes. However, for many species/groups, with few readily observable characteristics, morphological identification and counting have historically been a difficult task. Over the past decades, microbiologists have endeavored to apply and extend molecular techniques to address questions in microbial ecology. These culture-independent studies have generated new insights into microbial ecology. One such strategy, metagenome-based analysis, has also proved to be a powerful tool for plankton research. This mini-review presents a brief history of plankton research using morphological and metagenome-based approaches and the potential applications and further directions of metagenomic analyses in plankton ecological studies are discussed. The use of metagenome-based approaches for plankton ecological study in aquatic ecosystems is encouraged.
Nonlinear Dynamics of a Nutrient-Plankton Model  [PDF]
Yapei Wang,Min Zhao,Chuanjun Dai,Xinhong Pan
Abstract and Applied Analysis , 2014, DOI: 10.1155/2014/451757
Abstract: We investigated a nonlinear model of the interaction between nutrients and plankton, which was addressed using a pair of reaction-advection-diffusion equations. Based on numerical analysis, we studied a model without diffusion and sinking terms, and we found that the phytoplankton density (a stable state) increased with the increase of nutrient density. We analyzed the model using a linear analysis technique and found that the sinking of phytoplankton could affect the system. If the sinking velocity exceeded a certain critical value, the stable state became unstable and the wavelength of phytoplankton increased with the increase of sinking velocity. Furthermore, band patterns were also produced by our model, which was affected by the diffusion and sinking of phytoplankton. Thus, the change in the diffusion and sinking of phytoplankton led to different spatial distributions of phytoplankton. All of these results are expected to be useful in the study of plankton dynamics in aquatic ecosystems. 1. Introduction Plankton play an important role in the ecology of the ocean and climate because of their participation in the global carbon cycle at the base of the food chain [1]. In certain environmental conditions, lakes, reservoir, and marine waters may experience plankton or algal blooms [2, 3]. However, the local and global impacts of plankton blooms on water quality, carbon cycling, and climate may be damaging. If nutrient source is abundant, and some conditions are satisfied, blooms may become long-term events that affect ecosystems. Plankton blooms can change the types of species present at the base of the aquatic food web and affect human health. Thus, the study of plankton dynamics is currently of major interest. In the past years, there were many researches on the model between nutrient and phytoplankton and zooplankton [4–6]. A larger number of researchers have attempted to model the relationship between nutrient and phytoplankton and zooplankton, to investigate the dynamics in plankton model. Truscott and Brindley [7] presented a model for the evolution of phytoplankton and zooplankton populations which resembles models for the behavior of excitable media. Luo [8] investigated phytoplankton-zooplankton dynamics in periodic environments, where eutrophication was considered. El Saadi and Bah [9] modeled phytoplankton aggregation using numerical treatment and explored the asymptotic behavior of the model. Banerjee and Venturino [10] studied a phytoplankton-toxic phytoplankton-zooplankton model and found that the toxic phytoplankton does not drive the
On the origin of plankton patchiness  [PDF]
J. M. G. Vilar,R. V. Sole,J. M. Rubi
Physics , 2002, DOI: 10.1016/S0378-4371(02)01322-5
Abstract: Plankton is the productive base of aquatic ecosystems and plays a major role in the global control of atmospheric carbon dioxide. Nevertheless, after intensive study, the factors that drive its spatial distribution are still far from being clear. The models proposed so far show very limited agreement with actual data as many of their results are not consistent with field observations. Here we show that fluctuations and turbulent diffusion in standard prey-predator models are able to accurately and consistently explain plankton field observations at mesoscales (1-100 km). This includes not only the spatial pattern but also its temporal evolution. We explicitly elucidate the interplay between physical and biological factors, suggesting that the form in which small scale biotic fluctuations are transferred to larger scales may constitute one of the key elements in determining the spatial distribution of plankton in the sea.
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