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131.
厦门西港引发有害硅藻水华磷的阈值研究   总被引:12,自引:1,他引:11  
林昱  林荣澄 《海洋与湖沼》1999,30(4):391-396
1995年10月,在厦门市国家海洋局第三海洋研究所的陆基水池中,应用海洋围隔生态系实验技术,研究了在无海流、盐度等因子干扰的情况下,磷的形态、分布及其与浮游植物生物量的相关性。结果表明,海水中的可溶性无机磷(DIP)随时间里指数函数减少。浮游植物生物量主要与可溶性无机磷密切相关:[Chl-a]=A×e-B[PO4],这种相关的浮游植物生物量表现2d左右的滞后现象。还探讨了限制浮游植物增殖的DIP的最低浓度为0.3-04μmol/L,从DIP表现浓度估算浮游植物可能达到的最大生物量为[Chl-a]=10mg/m3,并由此估算出引发中肋骨条藻赤潮的DIP的阈值为1.2μmol/L,作为赤潮预测预报的参考。  相似文献   
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133.
五种海藻对虹鲍的诱食作用   总被引:4,自引:0,他引:4  
吴永沛 《台湾海峡》1999,18(2):181-185
采用自由择食和非自由择食实验的方法,研究5种海藻Lessonia variegatq,Darvillaea aularctina,Porphyra columbina,Macrocystis pyrifera,Ecklonia radiata对实验虹鲍Haliotis iris的诱食作用。结果表明,5种海洋藻类的诱食作用呈显著性差异。  相似文献   
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135.
Synoptic ship and satellite observations were performed of the Kuroshio warm-core ring (KWCR) 93A and its adjacent waters, off Sanriku, northwestern North Pacific, between early April and late June 1997. The temporal and spatial distribution of chlorophylla (Chl-a) and sea surface temperature in the study area were analyzed using data from ADEOS Ocean Color and Temperature Scanner (OCTS) and NOAA Advanced Very High Resolution Radiometer (AVHRR). The objective of this study was to describe the temporal and spatial variability of the spring bloom and understand its relationship with the changes in the hydrographic structure of these waters in and around KWCR 93A. The maximum value of Chl-a concentration in the ring was less than 1 mg/m3 during April. The spring bloom in the ring occurred early in May and the relatively high maximum (>1.0 mg/m3) continued from early in May to mid-June. In late June, a ship-observed surface Chl-a concentration of less than 0.4 mg/m3 suggests that the spring bloom had already declined in and around KWCR 93A. Double spiral structures of warm and cold streamers appeared from late April to mid-May, which may have an influence on the occurrence of the spring bloom in and around the ring. In this episodic event, the warm streamer can maintain the available potential energy of the ring and the strength of upwelling around the ring. The cold streamer provided water with a high Chl-a concentration to the surface layer of the ring. In order to understand the temporal and spatial variability of Chl-a distribution in the ring, the behavior of the warm and cold streamers needs to be taken into consideration.  相似文献   
136.
In order to examine the applicability of remotely-sensed ocean color for the estimation of phytoplankton biomass and primary production in the Oyashio region, the western subarctic Pacific, vertical distributions of chlorophylla concentration and primary production were observed in April and May 1997. Spring bloom was observed in both April and May, and the surface concentration of chlorophylla exceeded 40 mg m−3. The relationship between the standing stocks of chlorophylla within the layer from the sea surface to one optical depth (0–1/k layer) and the surface chlorophylla concentration is expressed as a Michaelis-Menten equation. The mean ratio of the standing stock of chlorophylla in the euphotic layer to that in the 0–1/k layer was 4.41, this ratio did not significantly differ from 4.61 which was obtained at homogeneous distribution of chlorophylla within the euphotic layer. These facts suggest that the distribution of chlorophylla could be assumed to be homogeneous in the euphotic layer during the spring bloom. Results of primary production measurements by simulatedin situ method were compared with those by an algorithm with two variables; chlorphylla and non-spectral PAR. Daily primary production in the euphotic layer estimated by the algorithm varied in a range of 38–274% of that estimated by incubation, although the primary productions by the algorithm agreed with those by the incubation at a half of stations. Primary production within the euphotic layer calculated using simply the surface data was the same as that estimated using vertical distribution of chlorophylla. These results show that the primary production in the euphotic layer may be estimated from the remote sensed measurements during the spring bloom in the Oyashio region.  相似文献   
137.
2021年7月末至10月初,位于黄海沿岸的青岛市西海岸新区琅琊台湾贡口拦海坝处出现大量悬浮生长的大型红藻。为明确该类群的分类地位,探究其生物学特征,对该处红藻群体展开了实地调研,并采集相关样本开展了形态鉴定和分子系统发育分析。该群体主要由一种红藻组成,藻体紫红色、圆柱形,质软多肉,高度可达20cm,不规则互生分枝,分枝基部强烈缢缩、顶端尖细;藻体主轴横截面观可见较小的含色素外皮层细胞以及较大的近圆形假薄壁细胞和分布在髓层中央的散乱、疏松的丝状细胞。结合分子标记rbc L和cox I基因的系统发育分析结果,该物种被鉴定为细弱红翎菜(Solieria tenuis Zhang et Xia)。与历史研究记录不同,贡口拦海坝处的细弱红翎菜群体缺乏固着器和繁殖结构,悬浮性营养生长,所在海域丰富的氮磷营养可能为其快速生长提供了物质基础,在生长高峰期该群体总生物量约6 t (干重),是一次局部区域性小规模“藻华”。细弱红翎菜的悬浮生态型和暴发性增殖现象表明该物种可能具有较强的环境适应性,其生理特征和潜在的生态风险需进一步关注。  相似文献   
138.
Toxic harmful algal blooms(HABs) can cause deleterious effects in marine organisms, threatening the stability of marine ecosystems. It is well known that different strains, natural populations and growth conditions of the same toxic algal species may lead to different amount of phycotoxin production and the ensuing toxicity. To fully assess the ecological risk of toxic HABs, it is of great importance to investigate the toxic effects of phycotoxins in marine organisms. In this study, the short-te...  相似文献   
139.
前期风场控制的太湖北部湖湾水动力及对蓝藻水华影响   总被引:7,自引:6,他引:1  
为明确前期风场对太湖北部湖湾水动力及蓝藻水华分布的影响,对2008年9月梅梁湾及贡湖湾水文、水质及气象开展了同步观测,结果表明:受前期东北风影响,梅梁湾及贡湖湾表层、中层及底层湖流流向均顺风向自湾内流向湾外,两个湖湾均不存在补偿流.表层湖流对风场变化响应敏感,而中场及底层流场对风场变化响应存在显著滞时.在偏南风作用下,梅梁湾表层湖流能快速形成顺时针环流.在偏西风作用下,贡湖湾表层湖流流向虽未发生偏转,但是湖流流速显著减小并导致流速沿水体垂向呈递增分布.观测期间水动力强度对太湖北部湖区叶绿素a浓度垂向分层及蓝藻水华水平漂移均具有重要影响.在水动力滞缓水域,蓝藻水华易在水表发生漂移堆积.在水动力强度较大水域,强烈的垂向混合作用能使蓝藻沿水深方向混合均匀,降低水华暴发风险.相对于水动力条件,营养盐对叶绿素a浓度空间分布的影响较弱.  相似文献   
140.
通过连续9d(2010年7月24日至2010年8月1日)对太湖水体理化指标垂向分层的高频率观测,揭示太湖多指标垂向分层规律.观测表明:(1)太湖中各水质指标频繁出现分层现象,但不稳定;(2)分层的主要控制因素包含气温的日变化、蓝藻水华堆积与风浪扰动等;(3)气温和太阳辐射日变化影响水温分层,水温垂向变幅可达3.94℃,...  相似文献   
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