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161.
The toxicity of seven major HAB (harmful algal bloom) species/strains, Prorocentrum donghaiense, Phaeocystis globosa, Prorocentrum micans, Alexandrium tamarense (AT-6, non-PSP producer), Alexandrium lusitanicum, Alexandrum tamarense (ATHK) and Heterosigma akashiwo were studied against rotifer Brachionus plicatilis under laboratory conditions. The results show that P. donghaiense, P. globosa, P. micans, A. tamarense (AT-6), or A. lusitanicum could maintain the individual survival and reproduction, as well as the population increase of the rotifer, but the individual
reproduction would decrease when exposed to these five algae at higher densities for nine days; H. akashiwo could decrease the individual survival and reproduction, as well as population increase of the rotifer, which is similar
to that of the starvation group, indicating that starvation might be its one lethal factor except for the algal toxins; A. tamarense (ATHK) has strong lethal effect on the rotifer with 48h LC50 at 800 cells/mL. The experiment on ingestion ability indicated by gut pigment change shows that P. donghaiense, P. globosa, P. micans, A. tamarense (AT-6) and A. lusitanicum can be taken by the rotifers as food, but A. tamarense (ATHK) or H. akashiwo can be ingested by the rotifers. The results indicate that all the indexes of individual survival and reproduction, population
increase, gut pigment change of the rotifers are good and convenient to be used to reflect the toxicities of HAB species.
Therefore, rotifer is suggested as one of the toxicity testing organisms in detecting the toxicity of harmful algae.
Supported by the Knowledge Innovation Program of Chinese Academy of Sciences (No. KZCX2-YW-208), National Natural Science
Foundation of China (No. 40821004, U0733006) and National Basic Research Program of China (973 Program, No. 2001CB409700) 相似文献
162.
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
163.
XIE Zhihao) ) XIAO Hui) TANG Xuexi) CAI Hengjiang) ) Marine Ecology Laboratory Ocean University of China Qingdao P. R. China ) Faculty of Life Science Biotechnology Ningbo University Ningbo P. R. China 《中国海洋大学学报(英文版)》2009,8(2)
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 2.5×104 cells mL-1 of P. donghaiense,the number of B. plicatilis increa... 相似文献
164.
本文分析了福建省平潭近海海域2013—2019年水文、水质及气象数据的主成分结果, 筛选出5个气象因子和4个水质因子作为输入指标, 以藻密度为输出指标, 分别演算了KNN (K-nearest neighbor)、RF (random forest)、GBRT (gradient-boosted regression Trees)以及Bagging (bootstrap aggregating)4种赤潮预警回归模型。对2013—2019年的802 组海洋监测数据归一化处理后, 随机选取80%的数据作为模型的训练样本, 剩余的20%作为模型验证数据。其中, 以风速、气温、海平面气压、叶绿素a浓度组合为输入指标时, KNN回归模型演算结果的精度较高(R2=0.624, RMSE=0.821μg·L-1, MAE=0.836μg·L-1)。在没有叶绿素a浓度监测指标的海域, 构建了以叶绿素a浓度为输出指标, 气温、日照、风速、AOI(apparent oxygen increase)组合为输入指标的BP神经网络赤潮模型, 该模型也具有较好的预警精度(R2=0.651, RMSE=0.062μg·L-1, MAE=0.033μg·L-1)。本研究结果可为平潭海域的赤潮预警研究提供参考。 相似文献
165.
长江三角洲末次盛冰期的气候波动 总被引:2,自引:0,他引:2
通过对长江三角洲东部地区鹤鸣孔第一硬黏土层的孢粉、藻类分析,研究了该地区末次盛冰期的气候波动。结果表明,鹤鸣孔第一硬黏土层含种类较丰富的孢子、花粉和藻类化石,并可以划分为3个孢粉、藻类组合,代表了该地区末次盛冰期气候变化的3个阶段,反映了该地区末次盛冰期并不是一个持续的干冷状况,第一硬黏土层沉积的早期和晚期气候较温暖湿润,针阔叶混交林发育,而中期阶段气候偏冷,植被贫乏。 相似文献
166.
The primary production and chlorophyll a concentration of picoplankton (0.2 - 2 μm) , nanoplankton (2 - 20μm) and micro- plankton (20 -200 μm) are described in the northeastern Pacific Ocean near the Hawaii Islands during the six survey cruises from 1996 to 2003:DY85-4, DY95-7, DY95-8, DY95-10, DY105-11 and DY105-12.14. The primary production of carbon was in range from 76.8 to 191.9 mg/(m^2 · d) with an average of 116.1 mg/( m^2 · d) in the east region, and from 73.1 to 222.5 mg/( m^2 · d) with an average of 127.1 mg/( m^2 · d) in the west region, similar to the other oligotrophic regions of the Pacific Ocean investigated. The chlorophyll a concentration was about 0.1 mg/m^3 from the surface to the 50 m depth, about 0.2 -0.4 mg/m^3from 50 to 100 m, and gradually decreased below the 100 m depth. The picoplankton accounted for more than 70% of the total chlorophyll a in the upper layer ( surface to 125 m), but it decreased to less than 50% in depth below 125 m. The nanoplankton and microplankton combined only accounted for less than 30% of the total chlorophyll a in the upper layer, but showed a more even vertical distribution. 相似文献
167.
对南海北部C4站柱状剖面进行了高分辨率孢粉、藻类研究,部分样品作了AMS14C年代测定.根据孢粉成分的变化将南海C4站从下至上划分了3个孢粉组合带,依次为:1带(258-194cm)为以Pinus-Quercus(常绿)-Polypodiaceae-Pteridium-Pteris-Dicranopteris-Adiantum为主的孢粉带; 2 带(194-94cm)为以Pinus-Quercus(常绿)-Pteridium-Polypodiaceae-Microlepia-Dicranopteris为主的孢粉带; 3带(94-4cm)为以Pinus-Pteridium-Polypodiaceae-Quercus(常绿)-Microlepia-Dicranopteris为主的孢粉带.并相应恢复了南海北部9 800a BP以来3个植被、气候、古环境演替阶段,结合AMS14C测年资料,对C4站柱状地层时代划分作了讨论,为南海古气候、古环境演变研究提供了科学依据. 相似文献
168.
K. K. I. U. Arunakumara ZHANG Xuecheng 《中国海洋大学学报(英文版)》2008,7(1):60-64
169.
密云水库东西库区的水质与浮游藻类分析 总被引:3,自引:1,他引:2
湖泊生态工程因其净化效果好、投资小、运行简单等优点,近十多年来在我国受到了广泛关注,并得到了越来越多的应用.本文介绍了云南洱海污染治理的工程技术之一--桃溪河口净化工程的设计思路.该工程基于暴雨径流输送污染物的特征,将水力工程、土石工程与生物工程有效结合,通过在桃溪河口建立溢流堰,将桃溪正常来水导截入由桃溪河口9个废弃鱼塘改造而成的净化池进行净化.工程运行的水质监测表明,该工程已发挥一定的净化效果,对TN的去除率达55.2%-86.9%,其中对NO3-N和NH4 -N的去除率都较高,对P的去除率达76.4%-88.2%,对悬浮物的去除率达29.4%-49.5%. 相似文献
170.
藻类的生理生态学研究进展 总被引:4,自引:0,他引:4
藻类研究一直是植物学领域研究的一个重点,藻类研究包括诸多方面,而生理生态学研究又是其中的重点。本文从其生理学、生态学和生理生态学三个方面综述近年来藻类的生理生态学研究,并指出其发展方向。 相似文献