胶州湾浮游植物对营养盐添加的响应关系   总被引：12，自引：0，他引：12  

王勇  焦念志 《海洋科学》2002,26(4):8-13

于1998年8月、11月、1999年2月 ,在胶州湾采用现场实验的方法初步研究了浮游植物对营养盐添加的时间响应效果。分级叶绿素a的结果显示 ,网采浮游植物(netphytoplankton ,简称net ,20～200μm)对同时添加氮(N)与磷(P)营养盐有最明显的响应 ;1998年8月微型浮游植物(nanophytoplankton ,简称nano ,2～20μm)对铁(Fe)或N +P的添加有比较明显的响应 ,在1998年11月与1999年2月则几乎无营养盐限制nano 的生长 ;1998年8月与1999年2月超微型浮游植物(picophytoplankton ,简称 pico ,<2μm)对N +P或N的添加有较明显的响应。  相似文献   

Variations of nutrient elements and its effect on ecological environment off the Changjiang estuarine waters     

Lin Yi''an  Tang Renyou  Pan Jianming  Jin Mingming 《海洋学报(英文版)》2001,20(2):197-207

I~IOXThe water off the Changjiang EstUary is one of the ~ areas Of land-sea interactionwith complex current series and convening water masses, such as the Changjiang River diluting water fm the west, the HUangha As "dxed water frn the north as well as the TaiwanWad Current wedging fm the ~theaSt (Mao et al., 1963). TheSe water masses havePtovided rich nutrients for the gtDwth and rep~tion of planktons, leading to the fonnationOf the fishing ~ Off the Changjiang Estuary with active bio…  相似文献   

中国河口地球化学研究的若干进展   总被引：15，自引：0，他引：15  

张经 《海洋与湖沼》1994,25(4):438-445

在过去１０年的河口地球化学研究的基础上，总结了中国一些大的河口体系中的化学要素的行为特点。与世界上的大河流相比，中国河流中具有较高的营养元素和较低的痕量元素浓度。流域盆地的风化作用指数由北向南逐渐增加，这与世界上其它地区十分相似。在河口淡－咸水混合过程中，颗粒态的化学要素多呈稳定态分布模式，这与高的泥沙量，较轻的污染程度和水文动力作用相对较弱有关，并县对生态系统有显著的影响。考虑到化学要素在中国河  相似文献   

光强和营养盐对伪矮海链藻昼夜节律变化的影响

Ⅰ.细胞分裂、叶绿素α及活体荧光特性   总被引：2，自引：0，他引：2       下载免费PDF全文

杨小龙  朱明远 《海洋与湖沼》1993,24(1):87-92

于1989年1月 - 1989年8月采用连续培养和半连续培养方法进行了伪矮海链藻细胞分裂、叶绿素a含量和活体荧光特性与光、营养盐关系的研究。结果表明,细胞分裂、活体荧光、叶绿素a均呈现光照期的增长速率明显高于黑暗期的增长速率的日变化规律,荧光增强比则在光照期开始后或黑暗期结束时出现最高值;光强和营养盐不仅影响各指标日变化的幅度,而且还可改变荧光增强比峰值出现时间。因此,在研究细胞分裂、叶绿素a和荧光特性的昼夜节律时,必须考虑光和营养盐这两个重要因素。  相似文献   

Presentation of RISK-UE Project     

Pierre Mouroux  Benoît Le Brun 《Bulletin of Earthquake Engineering》2006,4(4):323-339

This paper is a presentation of an European project called RISK-UE, entitled: “An advanced approach to earthquake risk scenarios with applications to different European towns”. It gives the origin, the objectives and the organisation of the project, together with the content of the different workpackages comprising methodological aspects: different features of European town, seismic hazard, urban system exposure, vulnerability of current, historical and monumental buildings, vulnerability of lifelines and essential facilities, seismic risk scenario, with an application to the seven following cities: Barcelona, Bitola, Bucharest, Catania, Nice, Sofia and Thessaloniki. These studies were realized in close relation with the decisionmakers of these cities, in order that they implement Risk Management Plans and Plans of Action to effectively reduce seismic risk.  相似文献   

The South China Sea warm-core ring 94S and its influence on the distribution of chemical tracers   总被引：5，自引：1，他引：5  

Li Li  Thomas Pohlmann 《Ocean Dynamics》2002,52(3):116-122

 In this paper, the distributions of currents and chemical tracers were studied along two hydrographic sections across ring 94S, a warm-core ring found in the South China Sea. Results suggest that while currents on its offshore side maintained quasigeostrophic balance, such a balance was not reached on its onshore side. Therefore, it is suggested that interactions of ring 94S with the slope may play an important role: it may break down the quasigeostrophic balance and cause a deformation of the current field. The observed distribution of δ¹⁸O supports the hypothesis that water masses inside the ring originate from the Kuroshio. Distributions of chemical tracers reveal a strong vertical disturbance of the isolines at the edge of ring 94S, where it approaches the shelf. This phenomenon may play an important role in the vertical exchange of biochemical elements across the thermocline. Possible reasons, i.e., enhanced vertical mixing and upwelling, are discussed. Received: 16 May 2001 / Accepted: 5 November 2001  相似文献   

普洱二台坡超大型化探异常找矿前景     

谢岿锐  李开全  余乔富 《云南地质》2008,27(4):469-476

测区共分析15个元素,除Au外,其余14个元素都产生异常。对异常作因子分析、R型聚类分析,结合物探、遥感、地质、1：20万区域化探资料综合研究,提出了在此异常区寻找大型矿床的可能性。  相似文献   

Bertrand''s Law and Weinberg''s Principle and Their Extension     

Cao Yuqing  Hu Kuanrong 《世界地质(英文版)》2000,3(2)

Bertrand's law that the plant can't live in lack of some indispensable element, appropriate amount of the element will make the plant thrive but excessive amount of it will make the plant poisoning and even die was obtained through the study on the biologic adaptability in laboratory for the indispensable element manganese by G. Bertrand. E. D. Weinberg developed Bertrand's law as that certain amount of manganese was appropriate for the growth of some bacteria but not for the form of bacteriophage.The double threshold contents of elements indispensable for the organisms and their physiological effects can be extended to different hydrogeochemical zones of hydrogeological unit. Some elements are lack in the hydrogeochemical zone, in which the elements leaching and transfer are very strong the biological physiological effect is negative to the elements content. However, in the elements enrichment area caused by leaching and concentrating by evaporation or environmental pollution, the biological physiological effects are positive to the element content. The elements content in other areas which are in between two above types is appropriate for the organisms.From the hydrogeochemical study in Liliu , Shanxi province we obtained that the rate of KBD, IDD and dental caries are resulted from deficiency of elements Se, I and F in water (soil), respectively, the rate of diseases above is inversely related with the element content, while in the zone with excessive fluorine caused by enrichment and leaching, the rate of endemic fluorosis is positive to the fluorine content.  相似文献   

Summer phytoplankton blooms in the oligotrophic North Pacific Subtropical Gyre: Historical perspective and recent observations     

John E. Dore  Ricardo M. Letelier  Roger Lukas 《Progress in Oceanography》2008,76(1):2-38

The export of organic matter from the oceanic euphotic zone is a critical process in the global biogeochemical cycling of bioelements (C, N, P, Si). Much of this export occurs in the form of sinking particles, which rain down into the unlit waters of the deep sea. Classical models of oceanic production and export balance this gravitational loss of particulate bioelements with an upward flux of dissolved nutrients, and they describe reasonably well those areas of the ocean where deep winter mixing occurs. The surface waters of the North Pacific Subtropical Gyre (NPSG), however, are strongly stratified and chronically nutrient-depleted, especially in summer. Nevertheless, there is ample evidence that blooms of phytoplankton and subsequent pulses of particle export occur during the height of summer stratification in these waters, especially to the northeast of the Hawaiian Islands. These blooms impact regional bioelemental cycling and act as a food source to the deep-sea benthos. We review here numerous published observations of these events in the NPSG, and present new data collected at Station ALOHA (22.75°N, 158°W) during the first 176 cruises of the Hawaii Ocean Time-series program (1988-2005), along with results from transect cruises conducted in the region in 1996 and 2005. We suggest that the summer phytoplankton bloom can be considered a frequent, perhaps annual feature in the northeastern NPSG, and that its perceived stochastic nature is a manifestation of chronic undersampling in time and space. The bloom is typically dominated by only a few genera of large diatoms and the cyanobacterium Trichodesmium. It appears to be consistently supported by dinitrogen fixation, but the fate of the organic matter produced during the summer depends critically on the species composition of the responsible diazotrophs. We estimate that the summer bloom is responsible for up to 38% of N₂ fixation and up to 18% of N-based new production annually at Station ALOHA. We hypothesize that the spatial distribution, timing and magnitude of the bloom may be determined largely by the physical and biological processes controlling new phosphorus delivery into the euphotic zone during the summer and the preceding winter.  相似文献   

Effects of Corn Cob Produced Biochars on Urea Recovery from Human Urine and Their Application as Soil Conditioners          下载免费PDF全文

Yang Zhang  Zifu Li  Ibrahim Babatunde Mahmood 《洁净——土壤、空气、水》2015,43(8):1167-1173

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