Heterotrophic bacteria of the Dapeng Bay in the South China Sea: community structure, abundance, and the relationships of culturablity with environmental factors   总被引：1，自引：0，他引：1  

JIANG Fajun  HU Zhangli  HU Chaoqun 《海洋学报(英文版)》2010,29(4):88-97

The community composition,abundance and culturablity of heterotrophic bacterioplankton in the Dapeng Bay of the South China Sea were investigated by morphological method,bacterial cultivation and biochemical methods over an annual cycle.Aeromonas and Pseudomonas were the predominant genera among the Gram-negative bacteria.The bacterioplankton abundance fluctuated from 2.07×10 8 to 2.44×10 9 cells/dm 3 ,and culturable bacteria abundance ranged between 0.1×10 6 and 16.07×10 6 CFU/dm 3 .The Culturablity of heterotrophic bacteria ranged between 0.01% and 1.31%.The relationship between bacterial culturablity and the environmental factors was also studied in different sites of the Dapeng Bay.Throughout the bay,a significantly positive relationship was evidenced between bacterial culturability and temperature,meanswhile bacterial culturability was significantly inversely related with salinity.The positive relationship was shown at the central bay while a negative relationship was observed at the bay mouth and there was no significant correlation at top bay between bacterial culturablity and chlorophyll a of sea water.A positive relationship was found between culturability and DIN all the bay,but DIP showed a significantly negative relationship with bacterial culturability only at the mouth of the bay.  相似文献   

受迫流动下的枝晶生长相场法模拟研究     

朱昌盛  王军伟  王智平  冯力 《海洋学报》2010,32(10):7417-7423

基于耦合流场和热噪声的相场模型及合理高效的三维动态求解域加速算法,定量模拟了在受迫流动下枝晶的非对称生长及流速对迎流、背流两侧的温度分布和层流层分布的影响.计算结果表明,受迫流动使迎流、背流两侧温度的分布与层流层分布呈现不对称状态,导致迎流侧与背流侧的过冷度不同,而熔体施加于枝晶界面前沿迎流侧的力还不足以抑制过冷度的作用,结果造成枝晶迎流方向优先生长,从而产生倾向于散热方向的倾斜;同时,由于迎流侧的实际过冷度大于背流侧,有利于促进迎流一侧枝晶生长速度以及稳定侧向分枝生长,从而导致了侧向分枝的非对称生长.随  相似文献   

Comparison of six statistical approaches in the selection of appropriate fish growth models     

朱立新  李丽芳  梁振林 《中国海洋湖沼学报》2009,27(3):457-467

The performance of six statistical approaches,which can be used for selection of the best model to describe the growth of individual fish,was analyzed using simulated and real length-at-age data.The six approaches include coefficient of determination(R2),adjusted coefficient of determination(adj.-R2),root mean squared error(RMSE),Akaike's information criterion(AIC),bias correction of AIC(AICc) and Bayesian information criterion(BIC).The simulation data were generated by five growth models with different num...  相似文献   

图像端元全自动提取方法研究   总被引：1，自引：0，他引：1       下载免费PDF全文

齐建成  朱述龙  朱宝山  赵泳  李二森 《海洋测绘》2009,29(2):16-19

传统端元提取算法一般需要人工指定端元数目,易导致多选或漏选端元。提出了一种端元全自动提取方法,通过研究分类结果的均方根误差、端元间光谱相关性与端元数目的关系,设置两种循环结束条件,当分类结果的均方根误差最小或端元间恰未出现强相关现象时,获得最佳端元数。实验表明,该方法是正确有效的,能够克服现有方法的不足,提高了端元提取自动化程度。  相似文献   

探针药物法评价磺胺甲基异唑、甘草和连翘对牙鲆CYP2E1活性的影响     

韩现芹  李健  王群  刘淇  韩华  李吉涛  陈萍 《中国海洋大学学报(自然科学版)》2009,39(3)

采用探针药物法研究磺胺甲基异唑(SMZ)、甘草及连翘对牙鲆细胞色素P4502E1 (CYP2E1)活性的影响,为临床合理用药提供参考.将牙鲆随机分为4组,即对照组、SMZ组、甘草组和连翘组.依次每日口灌0.9%的生理盐水、口灌SMZ 150 mg/kg·bw、甘草30 mg/kg·bw和连翘100 mg/kg·bw.连续6 d后,第7天时4组牙鲆同时一次性腹腔注射探针药物氯唑沙宗,分别于注射给药后不同时间点采血.通过HPLC检测探针药物的血药浓度,计算药动学参数,间接评价各组对CYP2E1酶的活性影响.结果表明:氯唑沙宗在4组牙鲆体内代谢的药时曲线均符合二室模型.甘草组和连翘组氯唑沙宗的半衰期分别增加了0.311倍和0.799倍,均差异极显著(P<0.01);SMZ组与对照组差异不显著.药时曲线下面积SMZ组与对照组比较减少了0.277倍,甘草组增加了0.286倍,差异均显著(P<0.05);连翘组增加了0.865倍,差异极显著(P<0.01).总清除率(CL)SMZ组增加了38.83%,连翘组减少了46.88%,均差异极显著(P<0.01);甘草组减少了21.22%,差异显著(P<0.05).说明甘草,连翘对牙鲆CYP2E1的活性均具有明显的抑制作用,连翘的抑制作用高于甘草,SMZ对牙鲆CYP2E1的活性具有诱导作用,差异不显著.  相似文献   

形态学开闭运算在居民地边缘检测中的应用   总被引：1，自引：0，他引：1  

欧阳平  张玉方 《测绘通报》2009,(1)

居民地是遥感影像中重要的地形要素之一,在研究居民地影像特征的基础上,提出一种基于形态学开闭运算的居民地边缘检测算法.试验结果表明,该方法能很好地检测出居民地的边缘.  相似文献   

基于GIS的城市空间生长量算研究     

于卓  吴志华  孙玥 《测绘信息与工程》2009,34(6):33-35

分析了城市空间生长影响因素的空间特征差异及对空间操作的影响,探讨了这些影响因素作用强度的主要空间量算途径,给出了GIS功能支持下的城市空间生长量算思路。  相似文献   

利用MODIS数据识别水稻关键生长发育期   总被引：8，自引：0，他引：8  

孙华生  黄敬峰  彭代亮 《遥感学报》2009,13(6):1130-1146

利用遥感方法提取中国范围内的水稻关键生长发育期。首先, 对时间序列Terra MODIS-EVI(Enhanced Vegetation Index)进行傅里叶和小波低通滤波平滑处理, 然后, 根据水稻在移栽期、分蘖初期、抽穗期和成熟期的EVI变化特征, 实现对各个生长发育期的识别。通过将利用2005年MODIS数据识别的结果与当年气象台站的地面观测资料进行比较, 采用本研究中的识别方法得出的水稻各个生长发育期的绝对误差大部分小于16d, 经过F检验表明提取的结果与地面观测资料在0.05水平下具有显著一致性。研究中的信息提取方法可被用于其他年份的水稻生长发育期识别, 根据其他作物的生长发育特点, 也可能适合于提取其他作物的生长发育期。  相似文献   

GPS-RTK在水利工程测量中应用     

杨延有  贾晓堂 《江西测绘》2009,(2)

本文针对在水利工程测量中使用GPS-RTK作业出现的有关坐标高程转换、初始化、伪值等问题进行分析,通过实践提出解决问题的办法。  相似文献   

Experimental Study on the Interspecific Interactions Between the Two Bloom-Forming Algal Species and the Rotifer Brachionusplicatilis     

XIE Zhihao  XIAO Hui  TANG Xuexi  CAI Hengjiang 《青岛海洋大学学报(英文版)》2009,(2):203-208

The interspecific interactions between the rotifer Brachionus plicatilis and two harmful algal blooms （HAB） species were investigated experimentally by single culture method. B. plicatilis population and the growth of the two algae were compared at different algal cell densities. The results demonstrated that the B. plicatilis obtained sufficient nutrition from Prorocentrum donghaiense to support net population increase. With exposure to 2.5×10^4 cells mL^-1 of P. donghaiense, the number of B. plicatilis increased faster than it did when exposed to other four algal densities （5, 10, 15 and 20 × 10^4 cells mL^-1）, and the increase rate of B. plicatilis population （r） at this algal density was 0.104 ± 0.015 rd^-1. Cell densities of P. donghaiense decreased due to the grazing of B plicatilis. In contrast, Heterosigma akashiwo had an adverse effect on B. plicatilis population and its growth was largely unaffected by rotifer grazing. In this case, B. plicatilis population decreased and H. akashiwo grew at a rate similar to that of the control.  相似文献