Seasonality and Reproductive Phenology of Algae Inhabiting Littoral Pools in the Western Mediterranean     

Lisandro  Benedetti-Cecchi Francesco  Cinelli 《Marine Ecology》1993,14(2):147-157

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4种重金属离子对海洋三角褐指藻生长影响的研究   总被引：23，自引：0，他引：23  

张首临  刘明星  李国基  包万友  顾宏堪 《海洋与湖沼》1995,26(6):582-585

于１９９３年４月－１９９３年５月以Ｚｎ＾２＋，Ｃｄ＾２＋，Ｐｂ＾２＋，Ｃｕ＾２＋不同浓度的海水对三角褐指藻进行生长影响的研究。实验表明，Ｃｕ＾２＋对三角褐指藻生长的毒性最大，其９６ｈＥＣ５０为０．０１７ｍｇ／Ｌ。Ｐｂ＾２＋的毒性最小，其９６ｈＥＣ５０为０．４６８ｍｇ／Ｌ。４种重金属离子的毒性顺序是Ｃｕ＾２＋＞Ｃｄ＾２＋＞Ｚｎ＾２＋＞Ｐｂ＾２＋，除Ｃｄ＾２＋外，其他３种金属离子对该单细胞藻的生长安全  相似文献   

四川椎实螺属一新种(肺螺亚纲:基眼目,椎实螺科)     

金志良  刘月英 《海洋科学集刊》1997,(39):9-14

作者1987年于四川省乐山市大渡河尾段发现椎实螺属一新种,现命名为乐山椎实螺(Lymnaea leshanensis sp.nov.)。该种与日本琵琶湖产的 Lymnaea onychia 相似,但贝壳的形态、齿式、齿形、两性生殖系统的诸器官、外套膜的色带、个体大小、生活环境和动物区系均有所不同。前者属东洋区系,后者属古北区系。  相似文献   

珠江河口铜、铅、锌、铬和镉对单细胞藻类生长的影响   总被引：1，自引：0，他引：1  

朱卓洪  李飞永  陈金斯 《热带海洋学报》1992,(2)

通过现场采水样和实验室模拟,研究珠江河口环境在一连串变化过程中,当各种浓度的Cu,zn,Pb,Cr和Cd单独存在或共存时,对单细胞藻类——硅藻和扁藻的毒性影响。  相似文献   

The Reproductive Cycle of Ophioderma brevispinum (Echinodermata: Ophiuroidea)     

GORDON HENDLER  P. A. TYLER 《Marine Ecology》1986,7(2):115-122

Abstract. .The reproductive cycle of the brittlestar Ophioderma brevispinum is described using histological and organ index data for a population in Massachusetts, U.S.A. The cycle consists of a one month mid-summer spawning phase followed by gametogenesis and gradual gonadal growth during the winter, and greatly accelerated gonadal growth from May to June. At the end of the spawning season, oogonia proliferate near the base of the ovary, and a continuous layer of spermatogonia lines the testis. As oocytes grow to a maximum diameter of 350 um, yolk granules accumulate and the cytoplasm becomes less basophilic. Prior to spawning, the testis becomes branched and sulcate, and a whorl of spermatozoa produced by columns of spermatids accumulates in the lumen. Comparisons between the reproductive cycles of different populations of O. brevispinum and its congeners support the hypothesis that temperature may be a critical exogenous factor, but definitely not the only factor, in the initiation and duration of the growth and spawning phases of the ophiuroid reproductive cycle.  相似文献   

重金属锌,铅对菲律宾蛤仔的急性毒性试验   总被引：14，自引：1，他引：14  

刘琼玉  洪华生 《台湾海峡》1997,16(1):50-54

本文研究了必需元素Ｚｎ及非必需元素Ｐｂ对菲律宾蛤仔的急性毒性作用，得到Ｚｎ对其的４８ｈＬＤ５０和９６ｈＬＤ５０分别为１４７．９１、１６．４０ｍｇ／ｄｍ＾３；Ｐｂ对其的４８ｈＬＤ５０和９６ｈＬＤ５０分别为３１．６２、１４．２８ｍｇ／ｄｍ＾３。估算得到Ｚｎ、Ｐｂ对菲律宾蛤仔的安全浓度分别为０．８２、０．７１ｍｇ／ｄｍ＾３。  相似文献   

吡喹酮和克螨特复配驱虫制剂对一些水生饵料生物的毒性     

樊海平 《台湾海峡》2004,23(4):500-506

由吡喹酮和克螨特组成的复配制剂对小球藻、轮虫、蚤状溞、水蚯蚓和卤虫的毒性实验结果显示：复配制剂对轮虫的半致死浓度(LC50)为13．9mg／dm^3(24h)和3．03mg／dm^3(48h)．安全浓度(SC)为0．0432mg／dm^3；对蚤状溞的LC50为345．14mg／dm^3(24h)和17．5mg／dm^3(48h)，SC为0．0135mg／dm^3；对水蚯蚓的LC50为636．80mg／dm^3(24h)和79．07mg／dm^3(48h)，SC为0．366mg／dm^3；对卤虫无节幼虫的LC50为201．84mg／dm^3(24h)和8．91mg／dm^3(48h)．SC为0．00519mg／dm^3,复配制剂对水环境生物的破坏作用小．  相似文献   

Reproductive Cycle of the Caribbean Feather Star Nemaster rubiginosa (Echinodermata: Crinoidea)     

Philip V.  Mladenov Kevin  Brady 《Marine Ecology》1987,8(4):313-325

Abstract. The reproductive cycle of the comatulid crinoid Nemaster rubiginosa from Discovery Bay, Jamaica is described histologically. The cycle is annual and may be divided into (1) a "resting" phase (summer) in which most adults possess immature, unsexable gonads, (2) a recovery phase (early fall) marked by the re-initiation of gametogenesis and rapid gonadal growth, (3) a breeding phase (late fall and winter) during which the gonads are mature and repeated spawning likely takes place, and (4) a post-spawning phase (spring) during which relict gametes are removed from the shrinking gonads. Although unsexable individuals predominate during the "resting" phase, a small proportion of the adult population is unsexable at all times of the year. The reproductive condition of animals in the same month in two successive years was very similar, suggesting that the timing of reproduction is quite predictable from year to year. The re-initiation of gametogenesis in the early fall is correlated with both rising sea temperature and shortening daylength, and the October to March breeding season corresponds to the period of short daylengths at the study site. The well-defined and synchronized annual reproductive cycle of Nemaster rubiginosa contrasts with the more prolonged and variable reproductive cycles reported for other tropical crinoids and points to a diversity of breeding patterns among tropical crinoids.  相似文献   

欧氏六线鱼Hexagrammos otakii Jordan & Starks性腺发育的周年变化研究   总被引：1，自引：0，他引：1  

郑家声  王梅林  史晓川  张士璀 《中国海洋大学学报(自然科学版)》1997,(4)

根据对青岛附近水域欧氏六线鱼（已达性成熟年龄）性腺周年宏观和组织学观察，性腺发育可分为：①重复发育Ⅱ期；②开始成熟期；③接近成熟期；④临产期或产卵期；⑤产后期。按性腺指数变化并结合性腺组织切片确定，欧氏六线鱼性腺发育在青岛海区一年一个周期，繁殖期在１０月下旬至１２月，繁殖盛期是１１月下旬至１２月中旬。  相似文献   

虾蟹类亲体生殖营养需求研究的进展   总被引：10，自引：0，他引：10  

艾春香  李少菁  王桂忠  林琼武 《台湾海峡》2003,22(2):254-261

本文综述了虾蟹类生殖营养的最新研究成果,并讨论了各营养素对虾蟹类亲体成熟、生殖和幼体质量的影响．此外,就今后在虾蟹类亲体生殖营养方面开展深入研究提出了一些建议。  相似文献