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排序方式： 共有637条查询结果，搜索用时 15 毫秒
1.
陈义中;朱建荣 《海洋湖沼学报（英文）》2018,36(5):1586-1596
2-Methylisoborneol (2-MIB) is a cyanobacterial metabolite that is responsible for many taste and odor (T & O) complaints related to the aesthetics of drinking water and poses a problem for water authorities because it is recalcitrant during conventional water treatment. A numerical model was developed to simulate 2-MIB in the Qingcaosha Reservoir, an estuarine drinking water resource in the Changjiang estuary with known 2-MIB episodes. The objective of this study was to numerically simulate the generation and release processes of 2-MIB in the reservoir and to provide useful information for better management of drinking water resources experiencing T & O problems caused by cyanobacteria. The simulation results from 2009 to 2013 showed that the simulated 2-MIB concentrations corresponded well to the observational data. 2-MIB was released mainly during periods of low dissolved oxygen (DO) levels with an adequate potential sediment source. The temporal and spatial variations in nutrients, chlorophyll-a (Chl-a ), Cyanophyta and 2-MIB were presented and analyzed during 2009 to 2013. According to the study results, high-concentration areas and peak levels of 2-MIB can be controlled by inhibiting algal growth and increasing oxygen levels in the water, which can be achieved via adequate water exchange and oxygen exposure in the reservoir, respectively. 相似文献
2.
Jianing Lin ;Tian Yan ;Qingchun Zhang ;Mingjiang Zhou 《海洋湖沼学报（英文）》2016,34(4):642-653
In recent years, harmful algal blooms (HABs) have occurred frequently along the coast of China, and have been exhibiting succession from diatom- to dinoflagellate-dominated blooms. To examine the effects of different diatom and dinoflagellate HABs, the life history parameters of rotifers (Brachionus plicatilis Müller) were measured after exposure to different concentrations of HAB species. The HAB species examined included a diatom (Skeletonema costatum) and four dinoflagellates (Prorocentrum donghaiense, Alexandrium catenella, Prorocentrum lima and Karlodinium veneficum). Compared with the control treatment (CT), the diatom S. costatum showed no adverse impacts on rotifers. Exposure to dinoflagellates at densities equivalent to those measured in the field resulted in a reduction in all the life history parameters measured. This included a reduction in: lifetime egg production (CT: 20.34 eggs/ind.) reduced to 10.11, 3.22, 4.17, 7.16 eggs/ind., life span (CT: 394.53 h) reduced to 261.11, 162.90, 203.67, 196 h, net reproductive rate (CT: 19.51/ind.) reduced to 3.01, 1.26, 3.53, 5.96/ind., finite rate of increase (CT: 1.47/d) reduced to 1.16, 1.03, 1.33, 1.38/d, and intrinsic rate of population increase (CT: 0.39/d) reduced to 0.15, 0.03, 0.28, 0.32/d, for the dinoflagellates P. donghaiense, A. catenella, P. lima and K. veneficum, respectively. The results showed that the diatom S. costatum had no detrimental consequences on the reproduction and growth of B. plicatilis, however, the four dinoflagellates tested did show adverse effects. This suggests that dinoflagellate HABs may suppress microzooplankton, resulting in an increase in algal numbers. 相似文献
3.
Yizhong Chen ;Weiqing Lin ;Jianrong Zhu ;Shiqiang Lu 《海洋湖沼学报（英文）》2016,34(1):231-244
A hydrodynamic model and an aquatic ecology model of Dianshan Lake, Shanghai, were built using a hydrodynamic simulation module and the water quality simulation module of Delft3D, which is an integrated modelling suite offered by Deltares. The simulated water elevation, current velocity, and direction were validated with observed data to ensure the reliability of hydrodynamic model. The seasonal growth of different algae was analyzed with consideration of observed and historical data, as well as simulated results. In 2008, the dominant algae in Dianshan Lake was Bacillariophyta from February to March, while it was Chlorophyta from April to May, and Cyanophyta from July to August. In summer, the biomass of Cyanophyta grew quickly, reaching levels much higher than the peaks of Bacillariophyta and Chlorophyta. Algae blooms primarily occurred in the stagnation regions. This phenomenon indicates that water residence time can influence algal growth significantly. A longer water residence time was associated with higher algal growth. Two conclusions were drawn from several simulations: reducing the nutrients inflow had little effect on algal blooms in Dianshan Lake; however, increasing the discharge into Dianshan Lake could change the flow field characteristic and narrow the range of stagnation regions, resulting in inhibition of algal aggregation and propagation and a subsequent reduction in areas of high concentration algae. 相似文献
4.
The source and significance of three nutrients – nitrogen, phosphorous and silicon – were investigated by a modified dilution method performed on seawater samples from the Central Yellow Sea (CYS), in spring blooming period of 2007. This modified dilution method accounted for the phytoplankton growth rate, microzooplankton grazing mortality rate, the internal and external nutrient pools, as well as nutrients supplied through remineralization by microzooplankton grazing. The results indicate that phytoplankton growth during the bloom is mostly contributed by internal nutrient pools (KI=0.062–1.730). The external nutrient pools (KE=<0–0.362) are also of importance for phytoplankton growth during the bloom at some sampling sites. Furthermore, the contribution of the recycled-nutrient pool by remineralization (KR=<0–0.751) is significant when microzooplankton grazing rate was higher than 0.5 d−1 during the spring phytoplankton blooms in the Central Yellow Sea. Compared with internal phosphorus, internal nitrogen and silicon contribute more to the phytoplankton production at most sampling stations. 相似文献
6.
Tang Huijuan ;Xie Ping ;Xie Liqiang ;Chen Feizhou 《海洋湖沼学报（英文）》2006,24(3):278-284
A nutrient enrichment experiment was conductedin situ in Donghu Lake (30°33'N, 114°23'E), a shallow hypereutrophic lake in Hubei, China through an enclosure(each 2.5×2.5m by 2 m depth) method from July 15 to September 21, 2000. Three duplicated groups, including two treatments and one control, were designed as unfertilized control (C), nitrogen enrichment (N) and phosphorus enrichment (P), and were also compared with neighboring lake water. DenseMicrocystis bloom exclusively dominated in all the enclosures, while no bloom was observed in the lake. All the enclosures had much higher phytoplankton biomass, higher pH values, and higher transparency than the surrounding lake water. Neither nitrogen nor phosphorus addition had significant effect on phytoplankton composition and biomass due to very high nutrient concentration in the lake water. Suitable biological (absence of filter-feeding silver carp and bighead carp) and physical environment (high transparency, high stability and high pH) associate with saturated nutrient concentration contribute to the nuisanceMicrocystis bloom in the enclosures. 相似文献
7.
Anne Klöppel Martin Pfannkuchen Annika Putz Peter Proksch & Franz Brümmer 《Marine Ecology》2008,29(2):259-272
Sponges provide the largest number of biologically active natural products known from the marine environment and continue to be a very well studied phylum of marine fauna. The Mediterranean sponge Aplysina aerophoba accumulates brominated isoxazoline alkaloids such as Aplysinamisin-1, Aerophobin-2, Isofistularin-3 and the biotransformation product Aeroplysinin-1, which possesses, for example, antibiotic and cytotoxic properties. Until now, it is still being discussed which organisms – the sponge itself or associated microorganisms – are responsible for metabolite production. For cultivating Aplysina individuals under ex situ conditions, we surveyed relevant ecological factors in situ and controlled them in our aquarium system. We maintained A. aerophoba for more than 9 months and analysed changes of metabolite content and composition, microbial association as well as morphology in situ and ex situ under different light exposure. Although sponges showed slight reduction during maintenance, ex situ cultivation similar to in situ conditions provides a promising method to keep sponges and obtain their bioactive metabolites. 相似文献
8.
9.
2004年春季东海赤潮高发区COD分布及其与赤潮关系的初步研究 总被引：6，自引：0，他引：6
2004年4～5月初在东海赤潮高发区暴发的特大规模原甲藻赤潮前期和暴发初期对该海域进行的现场调查,并对该海域COD的分布特征进行了探讨。结果表明,赤潮暴发前COD为0.295～1.836mg/L,主要受陆源输入影响。根据其在局部海区底层出现的异常升高结合其他参数分析可对特定海区潜在赤潮暴发的可能性进行评估。赤潮暴发时COD为0.36～3.14mg/L,表层和中层与叶绿素存在显著正相关关系,表明其主要受生物影响。富营养化指数表明赤潮暴发前近一半海域已经处于富营养化状态,但COD对富营养化的贡献不如营养盐重要。 相似文献
10.
Joji Ishizaka Yasuhisa Kitaura Yasuharu Touke Hiroaki Sasaki Akihiko Tanaka Hiroshi Murakami Toshikazu Suzuki Kazumi Matsuoka Hideaki Nakata 《Journal of Oceanography》2006,62(1):37-45
High resolution SeaWiFS data was used to detect red tide events that occurred in the Ariake Sound, Japan, a small embayment known as one of the most productive areas in Japan. SeaWiFS chlorophyll data clearly showed that a large red tide event, which damaged seaweed (Nori) cultures, started early in December 2000 in Isahaya Bay, expanded to the whole sound and persisted to the end of February 2001. The monthly average of SeaWiFS data from May 1998 to December 2001 indicated that the chlorophyll peaks appeared twice a year, in early summer and in fall, after the peaks of rain and river discharge. The SeaWiFS data showed that the red tide event during 2000–2001 winter was part of the fall bloom; however, it started later and continued significantly longer than other years. Satellite ocean color data is useful to detect the red tide; however the algorithms require improvement to accurately estimate chlorophyll in highly turbid water and in red tide areas. 相似文献