Automatic cell object extraction of red tide algae in microscopic images

Extracting the cell objects of red tide algae is the most important step in the construction of an automatic microscopic image recognition system for harmful algal blooms.This paper describes a set of composite methods for the automatic segmentation of cells of red tide algae from microscopic images.Depending on the existence of setae,we classify the common marine red tide algae into non-setae algae species and Chaetoceros,and design segmentation strategies for these two categories according to their morphological characteristics.In view of the varied forms and fuzzy edges of non-setae algae,we propose a new multi-scale detection algorithm for algal cell regions based on border-correlation,and further combine this with morphological operations and an improved GrabCut algorithm to segment single-cell and multicell objects.In this process,similarity detection is introduced to eliminate the pseudo cellular regions.For Chaetoceros,owing to the weak grayscale information of their setae and the low contrast between the setae and background,we propose a cell extraction method based on a gray surface orientation angle model.This method constructs a gray surface vector model,and executes the gray mapping of the orientation angles.The obtained gray values are then reconstructed and linearly stretched.Finally,appropriate morphological processing is conducted to preserve the orientation information and tiny features of the setae.Experimental results demonstrate that the proposed methods can effectively remove noise and accurately extract both categories of algae cell objects possessing a complete shape,regular contour,and clear edge.Compared with other advanced segmentation techniques,our methods are more robust when considering images with different appearances and achieve more satisfactory segmentation effects.     

湛江港附近海域赤潮生物的种类调查

以光学显微镜对在湛江港附近海域采集的浮游生物进行观察,初步鉴定出赤潮生物——— 硅藻31种、甲藻10种、蓝藻1种,简要介绍了几种主要的赤潮生物的习性、分布和形成赤潮后对渔 业生产造成的损失。     

赤潮信息系统综合分析应用

对赤潮遥感信息及同步采集的赤潮优势种类的光谱数据与同步采集的生物、化学、水文、气象等相关观测数据作了分析,在VisualFoxpro集成系统环境下,研究了地物光谱数据处理算法,以及利用地物光谱数据提取赤潮优势种类等生物信息的方法,并阐述了赤潮生物优势种类识别和赤潮生物特征量分析的应用及赤潮生物的监测。     

The Monitoring of Red Tides Based on Modular Neural Networks Using Airborne Hyperspectral Remote Sensing

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.     

龙口市20年间海岸带变化的遥感监测

利用龙口市20年(1984～2004)来的12个时相的遥感图像,采用数字图像处理技术和目视解译方法提取了不同年代的海岸线、高潮线和低潮线。通过与基准线和人为因素的对比分析,研究海岸带的时空变化规律,及影响海岸带时空变化的主导因素。研究结果表明,龙口市海岸带总体变化趋势是:除人工海岸外,海岸带趋于向陆地移动,岸滩变窄、变低,潮间带变宽、坡度变缓,防潮能力下降;人类活动是导致海岸带时空演变的最根本因素,包括沿海基础设施的建设、农业结构的调整、采砂业的无序发展。其次是自然因素,包括沿岸流侵蚀与堆积以及海水入侵等。     

Assessing seawater quality with a variable fuzzy recognition model

With the rapid development of the marine economy industry, human exploitation of marine resources is increasing, which is contributing to the growing trend of eutrophication and frequent occurrence of red tide. Accordingly, investigations of seawater quality have attracted a great deal of attention. This study was conducted to construct a seawater environmental quality assessment model based on the variable fuzzy recognition model. The uncertainty and ambiguity of the seawater quality assessment were then considered, combining the monitoring values of evaluation indicators with the standard values of seawater quality. Laizhou Bay was subsequently selected for a case study. In this study, the correct variable model for different parameters was obtained according to the linear and nonlinear features of evaluation objects. Application of the variable fuzzy recognition model for Laizhou Bay, water quality evaluation and comparison with performance obtained using other approaches revealed that the generated model is more reliable than traditional methods, can more reasonably determine the water quality of various samples, and is more suitable for evaluation of a multi-index, multi-level, nonlinear marine environment system; accordingly, the generated model will be an effective tool for seawater quality evaluation.     

基于遥感影像信息的东昆仑活动断裂带研究

基于遥感影像（ Ｔ Ｍ 影像、黑白航片） 信息对东昆仑活动断裂带进行了研究,建立了活动构造影像空间信息识别模式,发现了新的分支活动断裂。东昆仑活动断裂带是青海省自然景观梯度带、地质灾害和气候转型带,这些特征构成其识别的宏观标志。     

不同海潮模型对中国沿海区域海潮负荷位移改正影响分析

选取FES2004、EOT11a、TPXO7.2和Chinasea2010等4个海潮模型,首先通过矢量差评价不同海潮模型的潮波参数差异,然后利用中国大陆构造环境监测网络23个沿海测站的GNSS连续观测数据,通过计算不同海潮模型改正前后GNSS时间序列的wRMS,评价基于不同海潮模型的海潮负荷位移改正的有效性。结果表明,不同海潮模型的潮波参数存在mm级差异,且沿海区域差异远比内陆区域显著。此外,海潮负荷改正对中国沿海区域测站坐标时间序列wRMS影响较大,大部分测站坐标时间序列进行海潮负荷改正后,wRMS减小10%~70%;改正后wRMS改善幅度与测站所属区域有关,东海沿岸测站wRMS的改善较渤海、黄海和东海沿岸测站更显著,可减小50%以上;wRMS改善程度的模型间差异为1%~2%,其中基于FES2004模型的改正对序列wRMS的影响最大,可达67.5%。     

Research on red tide occurrences using enclosed experimental ecosystems in west Xiamen Harbor, China—Relationship between various factors and red tide occurrences

A series of enclosed ecosystem experiments were conducted in a land-based tank near the seaside of West Xiamen Harbor. The results of experiments conducted in different seasons and years showed a repeatable phytoplankton succession. In this relatively stable ecosystem with added nutrients and trace metals, diatoms dominated initially, dinoflagellates dominated in the later stage, and dinoflagellate red tides eventually occurred. Vitamin B₁₂ enrichment may speed up this succession process. Stirring the water column could stop this process. Soluble Mn at a level of 3–4 μg/L in seawater, which also is the existing concentration of soluble Mn in Xiamen Harbor seawater, is sufficient for the multiplication of algae and occurrence of red tide. The present study showed that excessive soluble Mn in Xiamen Harbor cannot cause red tide, and that Fe was one of the important factors causing diatiom red tide in this present study. Project 39570145 supported by NSFC.     

A dinoflagellate <Emphasis Type="Italic">Cochlodinium geminatum</Emphasis> bloom in the Zhujiang (Pearl) River estuary in autumn 2009

A severe Cochlodinium geminatum red tide (>300 km2) was observed in the Zhujiang (Pearl) River estuary, South China Sea in autumn 2009. We evaluated the environmental conditions and phytoplankton community structure during the outbreak. The red tide water mass had significantly higher dissolved inorganic phosphate (DIP), ammonia, and temperature, but significantly lower nitrite, nitrate, dissolved inorganic nitrogen (DIN), and DIN/DIP relative to the non-red-tide zones. The phytoplankton assemblage was dominated by dinoflagellates and diatoms during the red tide. C. geminatum was the most abundant species, with a peak density of 4.13×107 cell/L, accounting for >65% of the total phytoplankton density. The DIN/DIP ratio was the most important predictor of species, accounting for 12.45% of the total variation in the phytoplankton community. Heavy phosphorus loading, low precipitation, and severe saline intrusion were likely responsible for the bloom of C. geminatum.     

FIVE RED TIDE SPECIES IN GENUS PROROCENTRUM INCLUDING THE DESCRIPTION OF PROROCENTRUM DONGHAIENSE LU SP. NOV. FROM THE EAST CHINA SEA

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.     

APPLICATION OF CLAYS TO REMOVAL OF RED TIDE ORGANISMS Ⅱ.COAGULATION OF DIFFERENT SPECIES OF RED TIDE ORGANISMS WITH MONTMORILLONITE AND EFFECT OF CLAY PRETREATMENT

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     

基于高分辨率遥感影像的湿地互花米草-芦苇混合交错带提取方法

互花米草是中国东部河口滩涂湿地主要入侵物种之一,其与本地物种芦苇竞争生长,形成了大范围的混合交错带。该交错带是研究湿地生态系统动态变化的重要信息,但因2种物种光谱的相似性及其在交错带的组成复杂性,使利用遥感技术提取交错带难度较大。因此,本文提出了一种将二者生长物候差异与其光谱特征相结合,考虑二者海陆位置分布差异,运用实测剖面观测数据确定光谱指标和阈值的综合提取方法。运用高分一号多光谱遥感数据,通过分析不同时相互花米草与芦苇冠层光谱差异,确定用来提取混合交错带的高分遥感影像,实现了研究区互花米草-芦苇混合交错带的提取。结果表明：不同时相宜选用不同的提取指标,本研究中在春季选择了近红外波段反射率,而秋季则选择了红波段反射率;2个时相的混合交错带范围存在明显差异,客观反映了互花米草与芦苇在不同季节的竞争状况。     

基于多源海事数据的大型船舶精细化分段乘潮研究

针对大型船舶长航道乘潮进港窗口期时长不充足问题,本文提出了基于船舶自动识别系统（Automatic Identification System,AIS）数据、港口潮汐数据、官方电子海图数据和航道地理位置数据等多源海事数据的大型船舶长航道精细化分段乘潮模型。首先,基于AIS数据采用K中心点算法对大型船舶乘潮航行行为特征进行挖掘,识别出大型船舶乘潮航迹关键点,计算大型船舶乘潮航行行为变化关键船位点。接着,结合长航道地理环境特征和大型船舶航行行为特征对长航道进行精细化分段,在此基础上基于港口潮汐数据构建大型船舶精细化分段乘潮窗口期计算模型。其次,设计乘潮历时自适应排列算法求解大型船舶乘潮最长窗口期;然后,以黄骅港综合港区航道为例验证了本文所提出的精细化分段乘潮模型。最后,基于电子海图数据利用地理信息系统平台实现大型船舶精细化分段乘潮三维动态推演,进一步验证大型船舶精细化分段乘潮航行的安全性。结果表明,该模型能够有效增加大型船舶乘潮进港窗口期时长,提高大型船舶乘潮进港效率,可为港航管理部门制定大型船舶进港计划提供理论指导。     

MODIS遥感数据提取赤潮信息方法与应用——以珠江口为例

近年来,中国沿海近岸二类水体中的赤潮频发,对海洋环境、社会经济和公众健康都造成较大危害,因此,针对近岸二类水体中较小范围赤潮的遥感监测分析有重要意义。本文的工作主要集中在:(1)分析典型赤潮海水、泥沙浑浊海水、赤潮泥沙混合海水,以及清洁海水的MODIS影像光谱特征;(2)分析叶绿素a法,温度法,荧光法和波段比值法,在近岸小范围赤潮识别应用中的优势和缺点;(3)提出监督分类的赤潮信息提取方法,其中典型赤潮样本的选取基于蓝绿波段反射率比值和MODIS 1,4,3波段。利用本方法,对珠江口海域2006年2月赤潮进行了提取,取得良好的效果。     

Toxic effects of Karenia mikimotoi extracts on mammalian cells

Karenia is one of the most harmful and representative red tide genus in a temperate zone. Blooms caused by this genus have resulted in massive fish death in the South China Sea and the East China Sea. However, the potential effects of this dinoflagellate on human health through the transfer of toxins via marine food webs, and the mechanisms of toxicity, are still unknown. Therefore, we examined the toxic effects of a strain of K. mikimotoi (isolated from the South China Sea) on the proliferation and morphol...     

顾及单木三维形态的无人机立体影像单木识别算法

单木参数对当前的森林资源管理、生态研究以及生物多样性保护等具有重要意义。无人机立体影像数据与单木识别算法为单木参数的低成本、自动化获取提供了基础。现有研究表明,常用的基于局部最大值搜索的单木识别算法面对密集林分时存在严重的漏识别问题,影响了参数提取的精度,因此本文提出了顾及单木三维形态的无人机立体影像单木识别新算法。算法首先综合利用无人机立体影像的高程与RGB光谱信息,通过随机森林分类进行林冠区的提取;然后利用形态学的多层腐蚀、膨胀与连通区标记进行树冠相连单木的分离与树冠中心点的提取,从而实现单木自动化识别。本文选取内蒙古大兴安岭林区和四川王朗林区的4块样地进行验证,以目视解译数据为参考,分别与基于高程值的局部最大值搜索算法（算法A）、基于RGB光谱亮度值的局部最大值搜索算法（算法B）进行比较。结果显示：本文提出的算法在4个样地的平均F1-score为94.17%,与算法A和算法B相比分别提高了15.85%和9.37%;而对于密集样地,本文提出的算法在查全率上相比算法A和算法B分别提高51.79%和35.64%。结果表明本文提出的算法在不同林区均能够实现较好的单木识别效果,特别是能够有效避免密集林分下的漏识别问题,为基于无人机立体影像的单木识别研究提供了一种新的思路。     

RESEARCH ON RED TIDE OCCURRENCES USING ENCLOSED EXPERIMENTAL ECOSYSTEM IN WEST XIAMEN HARBOR, CHINA RELATIONSHIP BETWEEN NUTRIENTS AND RED TIDE OCCURRENCE

ＩＮＴＲＯＤＵＣＴＩＯＮＰｈｏｓｐｈｏｒｕｓｉｓａｋｅｙｎｕｔｒｉｔｉｖｅｅｌｅｍｅｎｔｆｏｒｔｈｅｇｒｏｗｔｈｏｆｍａｒｉｎｅｐｈｙｔｏｐｌａｎｋｔｏｎ .Ｒｅｃｅｎｔｌｙ ,ｂｅ ｃａｕｓｅｏｆｅｎｖｉｒｏｎｍｅｎｔａｌｐｏｌｌｕｔｉｏｎ ,ｔｈｅｅｕｔｒｏｐｈｉｃａｔｉｏｎｐｒｏｂｌｅｍｓｉｎｃｏａｓｔａｌａｎｄｏｃｅａｎｉｃｗａｔｅｒｓｈａｖｅｂｅ ｃｏｍｅｍｏｒｅａｎｄｍｏｒｅｓｅｒｉｏｕｓ.Ｔｈｅｅｎｖｉｒｏｎｍｅｎｔｅｃｏｌｏｇｉｃａｌｒｅｓｐｏｎｓｅｉｎｔｈｅｌｏｎｇ ｔｅｒｍｔｏｔｈｅｆ…     

FES2004和GOT4.7海潮模型改正对全球PPP的影响特征及差异分析

针对目前少有全球范围PPP海潮负荷影响特征分析的问题,对比FES2004与GOT4.7海潮模型改正前后20个IGS站静态和动态PPP的解算结果,探讨2种模型下的潮波差异。实验结果表明,海潮负荷引起全球沿海站点的U方向位移达5 cm,但在地中海及波罗的海等陆间和内陆海域,并非单纯随站点离海岸线越近位移越大;海潮负荷在世界范围24 h静态PPP中对坐标误差RMS的影响达数mm,改正后收敛时间提升率最高达30%,但在某些岛屿和陆海交界地带对E、N方向的改正效果较差;基于2种模型计算的全球M₂分潮U方向差异在近海区域最大可达13 mm,且地理分布上与海潮本身无必然联系,负荷形变差异具有与海潮类似的周期性特征,在马来群岛附近达数mm,且半日潮差异高于周日潮与半月潮。     

施氏獭蛤的生态观察

施氏獭蛤(LutrariasieboldiiReeve)属暖水性贝类,分布于热带—亚热带海区,在我国东海和南海都有。据在广西和海南沿海的调查,它生活在潮下带至水深78m的沙或沙泥底质中。营埋栖生活,深度达21cm。生活海区的水温为8~32℃,盐度11 .50~33 00,pH值8. 2~8 .4,透明度4~7m。食物以底栖硅藻和有机碎屑为主。繁殖期在5~9月。其肉供食用,是较珍贵的食品,可以发展人工增养殖。