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1.
Coagulation of red tide organism cells with clays is discussed in theory and the effects of some fac-tors on it are studied.A quantitative model is presented which describes how the coagulation varies withpH in solution.According to the model,within the pH-range between pH_(zpc_a)and pH_(zpc_b),V_R is negativeand the coagulation is strong and strongest at pH=(pH_(zpc_a)+pH_(zpc_b))/2.It is also demonstrated that whenthe diameter of clay particles is close to that of cells,the collision probability is low,resulting in weakercoagulation.The model results have been corroborated by experiments and so are scientific and theoreticalbases for application.  相似文献   

2.
Study on the coagulation of four species of red tide organisms(Nitzschia pungens,Skeletonema costatum,Prorocentrum minimum and Noctiluca scintillans)with montmorillonite,and the effect ofmontmorillonite pretreatment on the coagulation shows that the capability for montmorillonite to coagu-late with them is in the order:N.pungens>S.costatum>P.minimum>N.scintillans.Thecoagulation is discussed from the aspects of the structure,shape,size,movement,habit,etc.of differ-ent species and the results are explained theoretically.The experimental results also indicate that the treat-ment of montmorillonite with acid can enhance its coagulating capability.This is due to the fact that Al(OH_2)_6~(+3),exchanged from the clay lattice by hydrogen ion H~+,forms hydroxy-aluminum polymers on thesurface of the montmorillonite.The hydroxy-aluminum polymers positively charge and increase the positivecharacteristic of the clay surface,and also serves as a bridge between adjacent surfaces of particles.Thesetwo functions enhance  相似文献   

3.
ImODUcnONThemacronutrientShitrogen,phosphorus,andsiliconhaveoftenboconsidedtodritthegroWthrateofmarinephytoplankton.RamtstudAsreveatalthattraeernetalAncronutrientSmaybeofsignilicanceintheerelogyofphytoplankton(RueterandUnsworth,l99l,Brandetal.,1983,HatheonandMore,l986).IronisacomPonentofmanyalgaeproteinsparticularlytwortantforbiosynthesisofchiorophyllandeleCtrntIansportrmCtionsofrespthetionandphotosynthesis,andisCrUdalfornitrogenmetaboljsmdriusehemeandiron-stilfUrcomPoundsarethecofact…  相似文献   

4.
Laboratory culture experiments showed that < 100μmol/L nitrate, amonium or mixture of aminoacids promote the growth of the red tide organism Prorocentrum micans Ehrenb, but that >100μmol/Lof ammonium, or mixture of glycine and glutamate was harmful to growth, and that orthophosphatewas P. micrns’main phosphorous soruce in the ocean. Presence of 80μmol/L EDTA, 0.5 to 1μmol/LFe~(3+), 1.0 to 20.0 μmol/L Mn~(2+) 0.1 to 0.4 μmol/L Co~(2+) in the culture medium could improvethe growth of P. micans. Vitamin B_1 promoted growth, but vitamin B_(12) and biotin did not. Theestimated minimum cell quotaS (q_ο) for nitrogen and phosphorus being 0.74 pmole/cell and 0.045pmole/cell show that phosphorus (more than nitrogen) limits the growth of P. micans in the study area.  相似文献   

5.
It is efficient and reliable to investigate the reed resources of Bosten Lake in Xinjiang, characterized by complicated types of reed land and very different reed growth using colour infrared aerial photos, Landsat images and multi band imagery. At first, on the basis of Landsat images and relevant data, we analyzed the ecological environment of the studied area, the characteristics of reed land types and imaging mechanism to determine the program for abstracting remote sensing information and aerial photographic conditions:On the processed Landsat images and aerial photos, we considered typically geographic features and reed land types, preselected ground sampling sections and sites, then determined indexes classifying reed land types according to sampling data and image characteristics, established various interpretation keys, drew distribution maps of reed land types and measured the area of various types of reed land following geometric correction. On the other hand, based on sampling values and hab  相似文献   

6.
Acetes chinensis always ovulate in the dark at night. Two to five hours before ovulation, the mature oocytes change from white to orange. In the meantime, meiosis of the oocytes occurs, and reaches the metaphase just prior to ovulation. If ovarian colour change starts in the dark at night but ovulation does not start by break of dawn, ovulation will be inhibited and meiosis of the cells will be blocked.  相似文献   

7.
This article reports main results of investigations on red tide in western waters of Xiamen Bay from Jan. to Dec. 1987, and elaborates on the relationship between the change of phytoplanktonic number and main environmental factors there. The cause and the method for judging and monitoring of red tide are discussed.  相似文献   

8.
In order to apply Satellite Remote Sensing(RS) to minig areas,some key issues should be solved,Based on an introduction to relative studying background,related key issues are propsed and analyzed oriented to the devel-opment of RS information science and demands of mining aress ,Band selection and combination optimization of Landsat TM is discussed firstly,and it proved that the combination of Band 3 ,Band 4 and Band 5 has the largest informaiton amount in all three-band combination schemes by both N-dimensional entropy method and Genetic Algorithm(GA) ,After that the filtering of Radarsat image is disccussed ,Different filtering methods are experimented and compared,and adaptive methods are more efficient than others,Finally the classification of Satellite RS image is studied,and some new methods including classification by improved BPNN (Back Propagation Neural Network) and classification based on GIS and knowledge anre propsed.  相似文献   

9.
Various aspects of studies on internal tides are reviewed .Both beam-like structure and modal structure of internal tides may exist in the ocean . Bottom intensifications are caused by many factors .e.g. upstream blocking , which is the result of nonlinear interaction among waves . The energy may decay very fast so that internal tides are mostly locally generated .Internal tides may have considerable residual currents.In a 3-D frame, numerical study revealed that internal waves may interfere with each other to cause strong motions fer from the generation sources.The mechanism that determines how the lee waves break to form various nonlinear waves such as solitary waves, hydraulic jumps and internal surges or bores remains unclear. Analytic study is difficult , so numerical method may be effective . A radiation condition on the open boundary must be employed. A complete 3-D model may gain interesting result.Study on internal tides in China is limited to field observations and data analysis .  相似文献   

10.
The practice has proved that it is an economic and effective method to investigate placer gold deposit by using multi-level information sources of remote sensing and multi-variate analysis methods, especially for the area with a sparse population and difficult condition like the Da Hinggan Mountains, China.The information sources used in our work includes Landsat TM, aerial infrared photography and their mosaic image maps and enlarged photos with different scales. According to statistic data, in the study area the gold-bearing rocks are mainly granite, alaskite, granodiorite and some old metamorphic rocks. On gold-bearing geological structures, the fault zones in the four directions (NE, NNE, NW and EW) are obvious, in which NNE and EW are the most key fault zones. On fluvial geomorphology the flow courses stored placer are in the tributaries of the 4th and 5th levels, especially in straight or slight curve reaches. On the basis of analysis the interpretative signs were set up, and the interpretative wo  相似文献   

11.
INTRODUCTIONAquiculturearearedtidesignalsoceanpollutionanddisaster.Althoughenvironmentscientistshaveconductedmanyin depthresearchesonthecauseandformationmechanismofredtide ,manyofitsaspectsarestillunknownbecauseredtideisacomplexphenomenonandtheecologic…  相似文献   

12.
A new technique is introduced in this paper regarding red tide recognition with remotely sensed hyper-spectral images based on empirical mode decomposition (EMD), from an artificial red tide experiment in the East China Sea in 2002. A set of characteristic parameters that describe absorbing crest and reflecting crest of the red tide and its recognition methods are put forward based on general pictre data, with which the spectral information of certain non-dominant alga species of a red tide occurrence is analyzed for establishing the foundation to estimate the species. Comparative experiments have proved that the method is effective. Meanwhile, the transitional area between red-tide zone and non-red-tide zone can be detected with the information of thickness of algae influence, with which a red tide can be forecast.  相似文献   

13.
Batch culture experiments were conducted with a red tide dinoflagellateScrippsiella trochoidea (Stein) Loeblch III collected from Jiaozhou Bay, Shangdong, China. Growth rates and oellular Chl—a were measured in media with iron and manganese ion concentrations controlled at different levels using EdTA-trace metal buffer systems. Cell density increased 3.2 times to 6.5 times over the range of lowest (0 mol/L) to highest (10−5 mol/L) iron and manganese ion concentrations. The range of cell density response was much lower than the range of total available iron and manganese, which was >100—fold that of Fe. This nonlinear relationship indicates that the cells adapt to make more efficient use of iron and manganese under limiting conditions. The cellular Chl—a content maximized after 3 days incubation and then decreased gradually under either iron or manganese limitation conditions. It indicated that the algae gained higher photosynthesis ability when transferred to a new environment. Growth responses to iron and manganese limitation can be both modeled according to the equation of Monod. The half—saturation constant for growth,k, is 4.6×10−8 mol/L for Fe and 5.1×10−8 mol/L for Mn. Our results showed that the iron availability in Jiaozhou Bay does not limit the growth ofS. trochoidea. Contribution No. 2831 from the Institute of Oceanology, Chinese Academy of Sciences. Project 9389008 supported by NSFC; Study supported by PDB6.  相似文献   

14.
Scrippsiella trochoidea (Stein) Loeblich III was grown in a nitrogen-or phosphorus-limited batch culture system in laboratory. Growth rates and cellular Chl-a were measured as functions of nitrate and phosphate concentrations. Growth rates were hyperbolic with both nitrate and phosphate concentration and fit the Monod equation. The minimum cell quota of nitrogen and phosphorus and then the optimum N∶P ratio ofS. trochoidea were estimated in this study. Measurement of phosphate concentration in Jiaozhou Bay suggest that phosphorus is the limiting factor ofS. trochoidea growth. Contribution No. 3679 from the Institute of Oceanology, Chinese Academy of Sciences. Project 39790110 supported by NSFC, the study aslo supported by the National Climbing Project B (PDBG-7-2) and partly supported by an MF grant from Hong Kong University of Science and Technology.  相似文献   

15.
A new planktonic dinoflagellate, Prorocentrum donghaiense I_a sp. nov., is described in the present paper. The water sample was collected from the Changjiang Estuary, the East China Sea. The species identification is based on shape, size, surface micro-morphology, ornamentation of thecal plates and the architecture of the pel‘iflagellar area and the intercalary bands as seen by fight and scanning electron microscope. Prorocentrum donghaiense Lu sp. nov. is compared with other prorocentrum species with respect to morphological characteristics and bloom behavior. It is not known whether Prorocentrum donghaiense Lu sp. nov produces phycotoxins like some other Prorocentrum species. Four other red tide species in the family Prorocentraceae (Dinophyceae), namely P. balticum, P. minimum, P.micans, P. triestinum, were examined and identified by light and scanning electron microscope. They have been recorded as bloom-forming species. Some aggregates of Prorocentrum are observed at the end of blooms. An event of strong discoloration caused by P. donghaiense could be detected by satellite sensor in the East China Sea in the late spring, of 1995.  相似文献   

16.
This paper proposes a red tide monitoring method based on clustering and modular neural networks. To obtain the features of red tide from a mass of aerial remote sensing hyperspectral data, first the Log Residual Correction (LRC) is used to normalize the data, and then clustering analysis is adopted to select and form the training samples for the neural networks. For rapid monitoring, the discriminator is composed of modular neural networks, whose structure and learning parameters are determined by an Adaptive Genetic Algorithm (AGA). The experiments showed that this method can monitor red tide rapidly and effectively.  相似文献   

17.
The study on the effect of NO on the growth of Chaetoceros curvisetus   总被引:1,自引:0,他引:1  
1 INTRODUCTION As a recently recognized information molecule in campaign of the “Molecule of the Year” by Sci- ence magazine, nitric oxide (NO) has attracted much attention from biologists and many other field scien- tists, for its very important physio…  相似文献   

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