Size distribution of individuals in the population of Asterias amurensis (Echinodermata: Asteroidea) and its reproductive cycle in China

To obtain baseline information on the size distribution of individuals in the population and reproductive features of sea star Asterias amurensis, monthly surveys of the population were carried out from May to December 2010 and March to May 2015 in coastal waters off Yantai, China. Spawning period was predicted by gonad and pyloric caeca indices as well as anatomical and histological methods. In the A. amurensis population, both large individuals (> 143 mm) and small ones (< 42 mm) were present in all sampling months. The population size structure was driven by the appearance of big cohorts of individuals less than 55 mm from May to August. The appearance of small individuals in all months suggested a prolonged spawning period at other sites in this bay or sea stars growing slowly because of food shortage. An arm length is a good predictor to wet body weight for A. amurensis. The development of gonad was relative slow from May to September but rapidly reached a peak of 20.95 in October 2010, and then dropped remarkably, indicating its spawning lasted from October to November. The same phenomenon was found from March to May 2015, suggesting another spawning during March to May, which was also verified by the results of histologic analysis on ovary. The gonad index (GI) and pyloric caeca index (PCI) tended to show a negative relationship. Due to the poor food availability, the reproductive characteristics of sea star were most likely affected by the shellfish mariculturein Yantai coastal waters

烟台近海大型底栖动物群落特征

根据2010年和2011年对烟台近海大型底栖动物的周年调查资料,采用优势度指数、物种多样性指数及Cluster聚类和MDS排序方法,进行群落特征和群落演替情况的。研究。结果表明,该海域共采集大型底栖动物176种,其中优势类群为多毛类。群落中的优势种主要包括短叶索沙蚕和不倒翁虫。烟台近海年平均生物量和丰度分别为16.72g/m~2和1022ind/m~2,且存在季节性差异。丰富度指数(D)、均匀度指数(J)和多样性指数(H')的年平均值分别为2.30、0.70和1.91。烟台近海大型底栖动物群落与底质和水深关系密切。群落特征发生了一定程度的变化,软体动物比例减少,多毛类比例增加。人类活动包括污水排放、养殖和捕捞、港口建设和船舶航运等干扰是导致上述变化的主要原因

Characteristics of macrobenthic communities in the estuary of Dagujia River and its adjacent water areas in Yantai, Shandong

为了解烟台大沽夹河河口及邻近海域大型底栖动物群落特征及受干扰情况,于2012年9月在上述区域设置12个采样点进行大型底栖动物群落调查和分析。对采集的生物样品进行物种鉴定、计数和称重,利用生物统计软件PRIMER计算优势度指数(Y)、Shannon-Wiener多样性指数(H')、Margalef丰富度指数(D)和Pielou均匀度指数(J),并进行等级聚类(CLUSTER)、非度量多维标度排序(non-metric multi-dimensional scaling,MDS)及丰度/生物量曲线(abundance and biomass curves,ABC)分析。共采集和鉴定大型底栖动物89..

Long-Term Trends of Macrobenthos in Southern Bohai Sea, China, in Relation toEnvironmental Changes

根据50多年来渤海南部海域大型底栖动物群落的历史资料,以及2011~2013年的现场调查数据,从渤海南部包括黄河口邻近海域及莱州湾大型底栖动物群落结构变化特征出发,分析了其长期演变的过程和规律,旨在阐明底栖动物群落的演变趋势,识别其重要的演变时段.并结合50年来渤海南部海域相关底栖环境因子的变化特征,探讨底栖动物群落的演变原因.过去50余年来,渤海南部海域大型底栖动物群落在物种数、生物量、丰度以及群落结构组成等方面都发生了较大的变动,具体表现为寿命长、体积大、具有高竞争力的K对策种的优势地位正逐渐丧失,而被寿命短、适应能力宽、具有高繁殖能力的R对策种所取代.按照50余年来渤海南部海域大型底栖动..

脱氧胆酸改性普鲁兰多糖纳米粒子制备与表征

通过酯化反应将脱氧胆酸偶联于普鲁兰多糖骨架形成具有两亲性的普鲁兰多糖衍生物(DP),采用纳米沉淀法制备纳米粒子(DPNs),考察制备条件对纳米粒子性质影响,为进一步将其作为药物载体的研究提供基础。衍生物DP结构通过FT-IR和1 H NMR表征,DPNs经透射电镜、动态光散射仪和zeta电位仪表征检测。获得不同取代度脱氧胆酸改性普鲁兰多糖衍生物,制备得到的纳米粒子呈球形,表面光滑规整,平均粒径100～300nm,zeta电位在-20mV左右。脱氧胆酸改性普鲁兰多糖衍生物通过纳米沉淀法能制备出纳米粒子,颗粒性质受制备条件影响

利用表面增强拉曼光谱快速鉴别卷烟生产中烟用香精香料

烟用香精香料的配方是卷烟工业中的核心技术,也是构建不同特色卷烟产品的关键之一。然而,现有的香精香料质量评价手段主要是人工嗅香和测定某些特定的物性指标,如折光指数、相对密度、酸值、挥发份总量等。在实验室科研中还有使用色谱-质谱联用等方法。但是上述手段仍存在较多问题,比如受主观意识影响,操作繁琐,前处理耗时长,费用高,灵敏度低等。基于此,本文开发了一种利用表面增强拉曼光谱技术结合主成分分析算法来快速鉴别实际生产中不同种类、不同掺兑样的烟用香精香料的方法。本文利用该方法成功获取不同种类、同一种类不同生产批次及烟用香精香料不同掺兑量样品的增强拉曼谱图。经主成分分析表明不同种类以及不同掺兑量样品的散点分布在不同区域,直接区分度高;同一种类不同生产批次的香精香料谱图类似,在散点图中较为集中;说明不同生产批次的样品以及不同掺兑量的样品都可以与其他种类的香精香料标准样品进行有效区分。本文利用表面增强拉曼光谱结合主成分分析算法对烟用香精香料进行检测的方法操作简易,检测快捷,成本低廉,结果便于分析识别,适用于烟用香精香料实际生产中的质量控制。国家自然科学基金(No.21522508)浙江中烟工业有限责任公司科技项目(No.ZJZY2016C002

Carbon and nitrogen stable isotopes variations in different tissues of macrobenthos in the intertidal zone

The technique of stable isotope analysis has been widely applied for the field of food web studies in recent years.However,few researches concerned about the impacts of different tissues used for analysis on the food web building.With the purpose of accuracy and comparability in the food web studies,the sampling tissues should be standardized.In this study,10macrobenthic species from the intertidal zone of the Yellow River Delta and Yantai were chosen as the target object to test the isotopic characteristic variations ofdelta~(13)C anddelta15 N at different body parts (whole bodies,muscles and gills).Our results show thatdelta~(13)C anddelta15 N values vary in different sampling tissues for most species,which indicates the different tissues used for analysis impact the food web building.To achieve a more accuracy and comparability result,suitable tissue should be primarily chosen for their food sources and trophic levels analysis.Namely,when the organism as predator,their muscles should first be chosen,for examples,adductor and foot muscles of mollusks,leg muscles of crabs and back muscles of fishes;when the organism as prey, most of their tissues,except for indigestible part(for polychaetes,the digestive tract contents should be removed) should be chosen for analysis on food sources and trophic levels of the secondary consumer,for example,whole soft parts of mollusks,the mixture of muscles and gills of crabs

Effect of seasonal hypoxia on macrobenthic communities in the Muping Marine Ranch, Yantai, China

Hypoxia is a common phenomenon in the world's oceans, especially in the shallow waters of coastal zones. Rates of hypoxia are increasing due to global climatic changes and anthropogenic activities. Hypoxia can cause mass mortality of marine animals and can have severe negative impacts on marine ecosystems. To better understand the effects of hypoxia on macrobenthic communities, a survey was carried out in the Muping Marine Ranch (Yantai) during June, August and September of 2016. Results showed that seasonal hypoxia led to changes in benthic community structure, especially in terms of species composition and dominant species. The dominant species were Polychaeta Lumbrinereis latreilli, Sternaspis scutata and Mollusca Endopleura lubrica in summer. The opportunistic species Lumbrinereis latreilli increased, whereas, sensitive species such as Leptomya minuta, Glycera chirori, Upogebia major, Pontocrates altamarimus, Eriopisella sechellensis decreased during the hypoxic period of August. Hypoxia also reduced biodiversity indices. The effect of hypoxia on abundance and biomass were not significant, mainly because of the increase in the opportunistic Lumbrinereis latreilli, which counteracted the decline in abundance and biomass of other species. Individual physiological tolerance to hypoxia was different among species. Lumbrinereis latreilli showed higher tolerance to hypoxia in dissolved oxygen (DO) = 1.0 mg/L compared to other species. Some sensitive species, such as Leptomya minuta, Upogebia major, Pontocrates altamarimus and Eriopisella sechellensis showed lower tolerance when DO < 2.5 mg/L. When DO increased to 2.5 mg/L, the macrobenthic community start to recover gradually. The recovery extent and time needed were closely related to the degree of seasonal hypoxia