基于C#语言的EPSW与CASS数据格式转换     

郭昕  武娟 《北京测绘》2009,(4):78-80,84

介绍利用C#程序实现EPsw软件与CASS软件数据格式转换,对两种数据格式进行了具体的分析,解决了EPSW图形数据转换成南方CASS标准图形时无测量属性、编码的问题,为数据共享及地形图测绘外业数据采集提供了一个简单而高效的方法。  相似文献   

Trophic modeling of the Northern Humboldt Current Ecosystem, Part II: Elucidating ecosystem dynamics from 1995 to 2004 with a focus on the impact of ENSO   总被引：1，自引：1，他引：0  

Marc H. Taylor  Jorge Tam  Vernica Blaskovic  Pepe Espinoza  R. Michael Balln  Claudia Wosnitza-Mendo  Juan Argüelles  Erich Díaz  Sara Purca  Noemi Ochoa  Patricia Ayn  Elisa Goya  Dimitri Gutirrez  Luis Quipuzcoa  Matthias Wolff 《Progress in Oceanography》2008,79(2-4):366

The Northern Humboldt Current Ecosystem is one of the most productive in the world in terms of fish production. Its location near to the equator permits strong upwelling under relatively low winds, thus creating optimal conditions for the development of plankton communities. These communities ultimately support abundant populations of grazing fish such as the Peruvian anchoveta, Engraulis ringens. The ecosystem is also subject to strong inter-annual environmental variability associated with the El Niño Southern Oscillation (ENSO), which has major effects on nutrient structure, primary production, and higher trophic levels. Here our objective is to model the contributions of several external drivers (i.e. reconstructed phytoplankton changes, fish immigration, and fishing rate) and internal control mechanisms (i.e. predator-prey) to ecosystem dynamics over an ENSO cycle. Steady-state models and time-series data from the Instituto del Mar del Perú (IMARPE) from 1995 to 2004 provide the base data for simulations conducted with the program Ecopath with Ecosim. In simulations all three external drivers contribute to ecosystem dynamics. Changes in phytoplankton quantity and composition (i.e. contribution of diatoms and dino- and silicoflagellates), as affected by upwelling intensity, were important in dynamics of the El Niño of 1997–98 and the subsequent 3 years. The expansion and immigration of mesopelagic fish populations during El Niño was important for dynamics in following years. Fishing rate changes were the most important of the three external drivers tested, helping to explain observed dynamics throughout the modeled period, and particularly during the post-El Niño period. Internal control settings show a mix of predator–prey control settings; however a “wasp-waist” control of the ecosystem by small pelagic fish is not supported.  相似文献   

The ignored but common nemertine Psammamphiporus elongatus from the Galician beaches (Spain), affected by the Prestige oil spill     

Alfonso Herrera-Bachiller  Pedro García-Corrales  Carmen Roldán  & Juan Junoy 《Marine Ecology》2008,29(S1):43-50

Nemerteans have been recorded in several studies of the sandy beaches, but usually these specimens have been only regarded as members of the Phylum, with no attempt at identification at any taxonomic level. This lack of identification is partly because of the sampling procedures used to collect beach macroinfauna. Nemerteans are fragile and need special care. They must be isolated and observed in vivo before using histological procedures, which must be employed for the taxonomical studies. This study deals with a sandy beach hoplonemertean, Psammamphiporus elongatus ( Stephenson 1911 ), only known for seven specimens from the Firth of Clyde (UK). This species is recorded for the first time from the Galician sandy beaches (NW Spain) where it reaches its maximum abundance. The species is described and illustrated and new data on its morphology and ecology are provided. The species was apparently affected by the 'Prestige' oil spill, and would be a good indicator of beach quality.  相似文献   

Crystallographic and NMR studies on sterols from green alga Chaetomorpha basiretorsa Setchell     

SHI Dayong  XU Feng  HE Juan  SHI Jiangong  FAN Xiao  HAN Lijun 《海洋学报(英文版)》2008,27(1):147-151

Chemical investigation of the ethanol extract of the marine green alga Chaetomorpha basiretorsa Setchell led to the isolation of a new sterol stigmast-4,28-dien-3α,6β-diol 1 in addition to the five known sterols of β-lawsaritol 2, saringosterol 3, 24-hydroperoxy-24-vinyl - cholesterol 4, β-stigmasterol 5, 29-hydroxystigmasta-5, 24 （28） -dien-3β-ol 6. Compounds were isolated by normal phase silica gel and Sephadex LH - 20 gel colum chromatography, reverse phase HPLC and recrystalization. Their structures were elucidated by spectroscopic methods including MS, IR 1D/2D NMR and X-ray analysis. Cytotoxicity of compounds was screened by using the standard MTF method. All these compounds were isolated from the green alga Chaetomorpha basiretorsa Setchell for the first time and they were inactive （50% inhibitory concentration was greater than 10 μg/cm^3） against KB, Bel -7402, PC - 3M, Ketr 3 and MCF-7 cell lines.  相似文献   

维生素对凡纳滨对虾N-乙酰-β-D-氨基葡萄糖苷酶的效应研究   总被引：1，自引：0，他引：1  

杜娟  谢晓兰  黄乾生  王烨  王丽琴  陈清西 《台湾海峡》2008,27(4)

以凡纳滨对虾中提取的N-乙酰-β-D-氨基葡萄糖苷酶(NAGase,EC 3.2.1.52)为研究对象,以对-硝基苯-N-乙酰-β-D-氨基葡萄糖苷(pNP-NAG)为底物,考察了几种养殖常用维生素对该酶活力的影响.结果表明,VB12、烟酸、核黄素等对酶活力基本上没有影响;而VB1、VB6、抗坏血酸等对该酶活力均有不同程度的抑制作用.随着抑制剂浓度增大,酶活力呈指数下降,测定导致酶活力下降50%的抑制剂浓度(IC50)分别为16.0、13.5、37.5mmol/dm3.进一步研究了VB6的抑制作用动力学,结果显示:VB6对酶的抑制作用为非竞争性可逆抑制,其对酶抑制常数(KI)为 15.2mmol/dm3.该研究对凡纳滨对虾的人工养殖具有一定的参考价值.  相似文献   

海水螺旋藻C-藻蓝蛋白富硒及其抗氧化特性   总被引：1，自引：0，他引：1  

成华  向文洲  吴华莲  彭娟  何慧  肖伟 《热带海洋学报》2008,27(5)

对海水钝顶螺旋藻Spirulina platensis C-藻蓝蛋白的富硒能力及含硒c-藻蓝蛋白对超氧阴离子(O2·)和羟基自由基(·OH)的清除作用进行了研究.结果表明,在添加低浓度硒(40-80mg·L-1)培养时,海水钝顶螺旋藻c.藻蓝蛋白对硒的富集效果显著强于淡水螺旋藻C-藻蓝蛋白.硒浓度为40mg·L-1时,C-藻蓝蛋白对硒的利用率最高,富硒系数最大(O.9%);硒浓度为60mg·L-1时,C-藻蓝蛋白含硒量最高(402mg·kg-1).含硒C-藻蓝蛋白比CJ藻蓝蛋白对超氧阴离子和羟基自由基的清除作用都有所加强,清除效应与C-藻蓝蛋白的含硒量及蛋白浓度呈正相关.C-藻蓝蛋白含硒量最高组(402mg·kg-1)在浓度为180μg·ml-1时,对超氧阴离子和羟基自由基的清除率分别可达到83%和35%,远高于同样条件下其他淡水种类相应蛋白的清除作用.研究结果显示,利用海水培养的螺旋藻能显著提高C-藻蓝蛋白的富硒能力和含硒C-藻蓝蛋白清除超氧阴离子的活性.此研究对开发具有抗氧化功能的含硒C-藻蓝蛋白显示出独特的技术优势和较大的应用潜力.  相似文献   

Decadal changes in hydrographic and ecological time-series in the Balearic Sea (western Mediterranean), identifying links between climate and zooplankton     

Fernandez de Puelles  Maria Luz; Molinero  Juan Carlos 《ICES Journal of Marine Science》2008,65(3):311-317

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Establishment and closure of the directed Florida whiting (Menticirrhus americanus) fishery and implications for North Atlantic right whale (Eubalaena glacialis) conservation and management     

Juan C. Levesque 《Marine Policy》2009

Today, ocean and coastal marine resource management is extremely complex. Marine resource managers are charged with conserving and managing many diverse species. Southern kingfish (Menticirrhus americanus), commonly known as whiting, are found from southern New England to Florida. During the fall through winter, western North Atlantic right whales (Eubalaena glacialis) are primarily found in the coastal nearshore waters off South Carolina, Georgia, and Florida, overlapping the whiting's range and habitat.  相似文献   

Sampling the vertical particle flux in the upper water column using a large diameter free-drifting NetTrap adapted to an Indented Rotating Sphere sediment trap     

Michael L. Peterson  Joan Fabres  Stuart G. Wakeham  Cindy Lee  Ivn J. Alonso  Juan Carlos Miquel 《Deep Sea Research Part II: Topical Studies in Oceanography》2009,56(18):1547-1557

Further development of the large, surface-tethered sediment trap (NetTrap) employed as part of the MedFlux program is described whereby the large collection capacity of the NetTrap is combined with an Indented Rotating Sphere/Sample Carousel (IRSC) sediment trap (IRSC–NT). This trap is capable of collecting particle flux either in a time series or settling velocity mode; settling velocity mode allows the collection of particles that fall within discrete settling velocity intervals. During short field deployments in the Mediterranean Sea the IRSC–NT configured in the settling velocity mode successfully collected unpoisoned samples for chemical and microbiological experiments. In addition to the development of the IRSC–NT, particle-settling behavior above and below the swimmer-excluding IRS valve was tested during on-deck experiments using a specially constructed water-tight trap. Chemical analyses of settling materials (published elsewhere) suggested that separation of particles by settling velocity was achieved. However, due to the motion of the ship, it was not possible to directly measure particle-settling velocities within the trap. Particle release from the IRS did not bias the apparent settling velocity spectrum. Rotation of the IRS did not engender turbulence at the surface of the sphere or within the skewed funnel below. Tests of different ball designs over the course of the MedFlux program showed that a “ridge and saddle” pattern was optimal for efficiently transferring particles under the IRS seal while still reducing swimmer entrance to the collection funnel. The large size of the IRSC–NT did not prevent it from drifting effectively with the current. Several modifications of the present design are proposed that should improve the accuracy of the settling velocity measurements.  相似文献   

MedFlux: Investigations of particle flux in the Twilight Zone     

Cindy Lee  Robert A. Armstrong  J. Kirk Cochran  Anja Engel  Scott W. Fowler  Madeleine Goutx  Pere Masqu  Juan Carlos Miquel  Michael Peterson  Christian Tamburini  Stuart Wakeham 《Deep Sea Research Part II: Topical Studies in Oceanography》2009,56(18):1363-1368

The MedFlux project was devised to determine and model relationships between organic matter and mineral ballasts of sinking particulate matter in the ocean. Specifically we investigated the ballast ratio hypothesis, tested various commonly used sampling and modeling techniques, and developed new technologies that would allow better characterization of particle biogeochemistry. Here we describe the rationale for the project, the biogeochemical provenance of the DYFAMED site, the international support structure, and highlights from the papers published here. Additional MedFlux papers can be accessed at the MedFlux web site (http://msrc.sunysb.edu/MedFlux/).  相似文献