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1.
Tang Wenjiao Geng Huixia Xi Yanjuan Zhang Qingchun Tang Xuexi Yu Rencheng 《中国海洋湖沼学报》2022,40(6):2312-2321
Dinoflagellate Alexandrium catenella is a cosmopolitan bloom-forming species with complex life cycle, the formation and germination of resting cysts are critical for its bloom dynamics. In the coastal waters of Qinhuangdao, A. catenella has been identified as the major causative agent for paralytic shellfish poisoning, but there is little knowledge concerning its resting cysts in this region. In this study, three surveys were carried out along the coast of Qinhuangdao from 2020 to 2021 to map the distribution of A. catenella resting cysts, using a quantitative PCR (qPCR) assay specific for A. catenella. The resting cysts were detected in surface sediments during all the three surveys, and their distribution patterns were similar. High abundance of resting cysts (maximum 1 300 cysts/g sediment (wet weight)) were found in a region (119.62°E–119.99°E, 39.67°N–39.98°N) northeast to the coastal waters of Qinhuangdao, where surface sediments were mainly composed of clay and silt (percentage above 50%). Prior to the formation of the A. catenella bloom in March 2021, the abundance of A. catenella vegetative cells in seawater had extremely significant positive correlation with the abundance of resting cysts in surface sediments, reflecting the important role of resting cysts in the initiation of A. catenella blooms. As far as we know, this is the first report on the distribution of A. catenella cysts along the coast of Qinhuangdao. The results will offer a sound basis for the future monitoring and mitigation of toxic A. catenella blooms and paralytic shellfish poisoning events in this region.
相似文献2.
Reduction of hydrocarbon contamination on viability of <Emphasis Type="Italic">Acartia pacifica</Emphasis> benthic resting eggs 总被引：2，自引：0，他引：2
The potential effect of hydrocarbon contamination on the hatching success of benthic resting eggs of Acartia pacifica in Xiamen Bay was investigated experimentally. The number of nauplii emerging from the sediment samples decreased with increasing Fuel Oil #0 concentration. The estimated rate of mortality increased markedly with the increase of Fuel Oil #0 concentration. Successive fuel Oil #0 concentrations from 50 mg/kg to 5000 mg/kg reduced the number of hatched nauplii by 3.8% -100%. The mortality of A. pacifica resting eggs due to Fuel Oil #0 contamination did not significantly increase as time progressed at each concentration level. The LC50 values of resting eggs, changing from 237.12 to 279.59 mg/kg, remained at an almost stable level in two months. The number of A. pacifica nauplii that hatched from the sediment at 10℃ was higher than those from the sediment at 30℃, which indicates that the toxicity of Fuel Oil #0 on A. pacifica resting eggs increases with increasing temperature. 相似文献
3.
LIU Zhifeng GAO Xiaoqiang YU Jiuxiang WANG Yaohui GUO Zhenglong HUANG Bin LIU Baoliang HONG Lei 《中国海洋大学学报(英文版)》2018,(2)
To investigate the changes of the biochemical composition of American shad(Alosa sapidissima) eggs and larvae at embryonic and early larval stages, samples were collected at different development stages from artificial fertilization to the end of yolk absorption including 2 h, 12 h and 30 h after fertilization and newly hatched larvae including 1 and 3 days after hatching. The composition of lipid, fatty acids, protein and amino acids were analyzed. The content of total protein exhibited a decreasing trend during embryogenesis and larval development, and a significant reduction was detected after hatching(P 0.05). The total lipid content remained relative stable. A significant reduction was detected in almost all amino acids after hatching except for glycine(P 0.05), while a significant decrease was found in the content of cysteine, proline, tyrosine, valine, isoleucine, leucine and phenylalanine during the yolk-sac phase(P 0.05). On the other hand, all the groups of fatty acids remained stable during the period of embryogenesis. But after hatching, a significant decrease was found in the content of C18:2n-6, C18:3n-6, SFA and ratio of EPA/ARA(P 0.05), while a significant increase was found in the content of C18:3n-3, C20:4n-6, C22:6n-3 and ratio of n-3/n-6(P 0.05). In conclusion, the combined data suggested that American shad utilizes the protein content as preferential energy substrates during embryonic and early larval developments with some specificity in the consumption of different amino acids. 相似文献
4.
《山地科学学报》2021,(7)
Numerous lakes in western China are excellent sites for understanding environmental change. However, what dominates rare earth element(REE) variations are still under debate in the lake environmental research. In this study, we selected 28 surface sediment samples from 17 lakes(i.e. largescale lakes, small water bodies, etc.) in the QinghaiTibet Plateau and Xinjiang area. These samples were analyzed to reveal the behavior of the REEs and major elements. These REE patterns are characterized by light rare earth element(LREE) enrichment, weak Ce anomaly(0.84-0.98, 0.94 on average) and negative Eu anomaly(0.53-1.00, 0.67 on average). The homogeneous REE patterns may reflect similar REE of the source lithologys. However, the REE abundances showed some significant differences. In this study, water chemistry data analyses inferred that the highly REE values appear possibly in the saltwater lake, and also related to carbonate mineral, whereas p H played a minor role in REE concentrations. In large-scale lakes(e.g. Lake Bosten and Lake Ulungur), the results showed that the relatively larger REE values are in the margins of lakes. Moreover, lower REE contents are towards the central region. Comprehensive study suggested that five major factors control the REE contents:(1) The REE tends to increase with the increase of the weathering intensity.(2) Likewise, heavy mineral(i.e. rutile, anatase, zircon, etc.) are probably primary in these sediments because they are highly enriched in the REE.(3) The contribution of Fe-Mn oxides is significant in sediments because their concentrations highly correlate with the REE.(4) The carbonate mineral(mainly calcite) played a significant role on the REE values in the lakes because the REEs are incorporated into the carbonate minerals generating the low REE concentrations.(5) Major element analysis, mineral analysis, and grain-size data analysis showed that the REE distribution is chiefly influenced by finer grain-size component of lake sediments due to the decreasing proportion of quartz and feldspar than coarser one. Moreover, the clay minerals in finer grain-size sediments can highly absorb the REE. 相似文献
5.
《中国海洋湖沼学报》2016,(5)
Ontogenetic changes in digestive enzyme activities and the amino acid(AA) profile of starry flounder,Platichthys stellatus,were investigated and limiting amino acids were estimated compared with the essential AA profile between larvae and live food to clarify starry flounder larval nutritional requirements.Larvae were collected at the egg stage and 0,2,4,7,12,17,24 days after hatching(DAH)for analysis.Larvae grew from 1.91 mm at hatching to 12.13 mm at 24 DAH.Trypsin and chymotrypsin activities changed slightly by 4 DAH and then increased significantly 4 DAH.Pepsin activity increased sharply beginning 17 DAH.Lipase activity increased significantly 4 DAH and increased progressively with larval growth.Amylase activity was also detected in newly hatched larvae and increased 7 DAH followed by a gradual decrease.High free amino acid(FAA) content was detected in starry flounder eggs(110.72mg/g dry weight).Total FAA content dropped to 43.29 mg/g in 4-DAH larvae and then decreased gradually to 13.74 mg/g in 24-DAH larvae.Most FAAs(except lysine and methionine) decreased 50%in 4-DAH larvae compared with those in eggs and then decreased to the lowest values in 24-DAH larvae.Changes in the protein amino acid(PAA) profile were much milder than those observed for FAAs.Most PAAs increased gradually during larval development,except lysine and phenylalanine.The percentages of free threonine,valine,isoleucine,and leucine decreased until the end of the trial,whereas the protein forms of these four AAs followed the opposite trend.A comparison of the essential AA composition of live food(rotifers,Artemia nauplii,and Artemia metanauplii) and larvae suggested that methionine was potentially the first limiting AA.These results may help develop starry flounder larviculture methods by solving the AA imbalance in live food.Moreover,the increased digestive enzyme activities indicate the possibility of introducing artificial compound feed. 相似文献
6.
波纹龙虾胚胎的离体培养及发育观察 总被引：1，自引：1，他引：0
对波纹龙虾不同发育时期的胚胎进行离体培养和显微观察。结果表明,初始培育的离体胚胎愈接近孵化期,其孵化率愈高(最高达80.0%);波纹龙虾胚胎发育经历受精卵、卵裂期、囊胚期、原肠期、中眼色素形成期、复眼色素形成期、心跳期、破膜前期和出膜期;胚胎在发育过程中颜色变化:橙红→深橙红→砖红→灰白→接近透明。 相似文献
7.
In this study, nest spawning was successfully induced by exogenous hormone injections and seawater flow stimulation, and optimum
condition for hatching fertilized eggs of burrow fish mudskipper,Boleophthalmus pectinirostris, was searched. Apart from spawning inside the nests, females also spawned outside the nests. The percentages of spawned nests
were 8.0% to 24.2%. Most eggs were observed adhered to the inner wall of the top half of the nest. Fertilization rates of
the nest-spawned eggs varied from 17.3% to 80.8%. Females could spawn after being artificially confined inside the nests with
males at ratios of 1∶1 or 1∶2, but the spawned eggs were not fertilized. Mean hatching rates of artificially fertilized eggs
incubated in round plastic buckets were 32.7%–70.6%, and in the net cages, were 4.2%–20.5%, respectively. Mean hatching rates
of nest-fertilized eggs incubated in the round plastic buckets were 33.6%–76.3%, and in the net cages, were 5.9%–25.2%. Results
showed that round bucket incubation was the best way for hatching fertilized eggs of mudskipper. Keeping the hatching seawater
flowing is an important way for increasing the hatching rates of the mudskipper fertilized eggs.
Supported by the NSFC (No. 30170739), and also supported by the Provincial Natural Science Foundation of Fujian Province (No.
B0210003). 相似文献
8.
Jin Jiapeng Wang Xiujuan He Min Li Jie Yan Chengzhi Li Yuanping Zhou Jilin Qian Jin 《中国海洋湖沼学报》2020,38(4):1188-1200
New acquired and reprocessed three-dimensional(3 D) seismic data were used to delineate the distribution and characterization of bottom simulating reflections(B SRs) in the Chaoshan Sag,in the eastern part of Dongsha Island,South China Sea.Three submarine canyons with different scales were interpreted from the 3 D seismic data,displaying three stages of canyon development and are related with the variation of BSR.Abundant faults were identified from the coherence and ant-tracing attributions extracted from3 D seismic data,which provide the evidence for fluid migration from deeper sediments to the gas hydrate stability zone(GHSZ).The uplift of Dongsha Island created a large number of faults and leads to the increased seafloor erosion.The erosion caused the cooling of the seafloor sediments and deepening of the base of the gas hydrate stability zone,which is attributed to the presence of paleo-BSR and BSR downward shift in the study area.Hence,methane gas may be released during the BSR resetting and gas hydrate dissociation related with seafloor ero sion. 相似文献
9.
《中国海洋湖沼学报》2018,(6)
A considerable part of the world's population is currently experiencing a severe scarcity of freshwater and nutrition. Inland aquaculture has the fastest growth in fresh waters, and this contributes to the eutrophication of freshwater bodies. The increase in freshwater aquaculture impacts on the increasing demand for fresh water. A way to overcome this is to develop aquaculture in saline lakes. This article discusses how saline and hypersaline lakes may contribute to overcome this problem and gives a list of fish and shrimp species that can be cultivated in saline lakes. Successful development of aquaculture depends on a healthy cultured stock of commercial fish and shrimps. A sustainable healthy stock of fish and shrimps can be only maintained using live food for the cultured fish larvae, fry and fingerlings. As well as Artemia spp. there are many other crustacean species with the potential for growing in hypersaline waters. At least 26 copepod species around the world can live at a salinity above 100 g/L with 12 species at a salinity higher than 200 g/L, and these all have excellent nutritional value. There is a high potential to use eukaryotic organisms of diff erent taxa in saline/hypersaline aquaculture for food, agri-aquaculture, diff erent industries and as food supplements. 相似文献
10.
ＩＮＴＲＯＤＵＣＴＩＯＮＲｅｓｔｉｎｇｅｇｇｓ,ｔｈｅｐｒｏｄｕｃｔｏｆｓｅｘｕａｌ(ｍｉｃｔｉｃ)ｒｅｐｒｏｄｕｃｔｉｏｎｏｆｍｏｎｏｇｏｎｏｎｔｒｏｔｉｆｅｒｓｌｉｋｅＢｒａｃｈｉｏ ｎｕｓｐｌｉｃａｔｉｌｉｓｏｒＢ .ｒｏｔｕｎｄｉｆｏｒｍｉｓ,ｃａｎｂｅｒｅａｄｉｌｙｓｔｏｒｅｄａｎｄｕｓｅｄｗｈｅｎｎｅｅｄｅｄｔｏｓｔａｒｔｍａｓｓｃｕｌｔｕｒｅｓｆｏｒｔｈｅｐｒｏｄｕｃｔｉｏｎｏｆｌｉｖｅｆｏｏｄｓｆｏｒｌａｒｖｉｃｕｌｔｕｒｅｏｆｍａｒｉｎｅｆｉｓｈｅｓａｎｄｃｒｕｓｔａｃｅａｎｓ.Ｔｈｅ… 相似文献
11.
Fertilised eggs of the devil stringer(I nimicus japonicus) were incubated at different salinity levels(21, 25, 29, 33, and 37), and then the hatching performances, morphological parameters, and biochemical composition(protein, lipid and carbohydrate) of the larvae were assayed to determine the influence of salinity on the early development of I. japonicus. The tested salinity levels did not af fect the times of hatching or mouth opening for yolk-sac larvae. However, the salinity significantly influenced the hatching and survival rates of open-mouthed larvae, as well as the morphology of yolk-sac larvae. The data indicated that 30.5 to 37.3 and 24.4 to 29.8 were suitable salinity ranges for the survival of embryos and larvae of I. japonicus, respectively. Larvae incubated at a salinity level of 29 had the greatest full lengths, and decreasing yolk volume was positively correlated with the environmental salinity. With increasing salinity, the individual dry weights of newly hatched larvae or open-mouthed larvae decreased significantly. Newly hatched larvae incubated at a salinity level of 29 had the greatest metabolic substrate contents and gross energy levels, while the openmouthed larvae's greatest values occurred at a salinity level of 25. Larvae incubated in the salinity range of 33 to 37 had the lowest nutritional reserves and energy values. Thus, the I. japonicus yolk-sac larvae acclimated more readily to the lower salinity level than the embryos, and higher salinity levels negatively influenced larval growth and development. In conclusion, the environmental salinity level should be maintained at 29–33 during embryogenesis and at 25–29 during early larval development for this species. Our results can be used to provide optimum aquaculture conditions for the early larval development of I. japonicus. 相似文献
12.
Induced nest spawning and artificial hatching of the fertilized eggs of mudskipper, Boleophthalmus pectinirostris 总被引：2，自引：0，他引：2
In this study, nest spawning was successfully induced by exogenous hormone injections and seawater flow stimulation, and optimum condition for hatching fertilized eggs of burrow fish mudskipper,Boleophthalmus pectinirostris, was searched. Apart from spawning inside the nests, females also spawned outside the nests. The percentages of spawned nests were 8.0% to 24.2%. Most eggs were observed adhered to the inner wall of the top half of the nest. Fertilization rates of the nest-spawned eggs varied from 17.3% to 80.8% Females could spawn after being artificially confined inside the‘nests with males at ratios of 1:1 or 1:2, but the spawned eggs were not fertilized. Mean hatching rates of artificially fertilized eggs incubated in round plastic buckets were 32.7%-70.6%, and in the net cages, were 4.2%-20.5%, respectively. Mean hatching rates of nestfertilized eggs incubated in the round plastic buckets were 33.6%-76.3%, and in the net cages, were 5.9%-25.2%.Results showed that round bucket incubation was the best way for hatching fertilized eggs of mudskipper.Keeping the hatching seawater flowing is an important way for increasing the hatching rates of the mudskipper fertilized eggs. 相似文献
13.
We studied the effect of pH(pH 5, 6, 7 and 8) on the hatching percentage, survival and reproduction of Artemia strains in Bohai Bay salt ponds. Strains included parthenogenetic Artemia from Bohai Bay(BHB), Artemia franciscana from San Francisco Bay, and A. franciscana artifi cially produced in salt ponds in Vietnam. The latter was included as a potential inoculum for biological management of salt ponds. The hatching percentage of cysts after 24 h and the survival rate of the tested Artemia strains were signifi cantly reduced when exposed to a culture medium at pH 5 for 18 d( P 0.05). The tolerance of Artemia to 48 h acid exposure varied with developmental stage, increasing in the following order: juvenile, nauplii, pre-adult, with maximum tolerance in adults. All strains of Artemia tested could not reproduce at pH 5. At pH levels from pH 6–8, a higher pH generally resulted in a shorter brood interval and enhanced ovoviviparity. Hence, we suggest that brine acidifi cation has a negative impact on Artemia populations in the Bohai Bay saltworks. Inoculation of Artemia with either local parthenogenetic Artemia or exotic A. franciscana should be feasible at pH 7–8. 相似文献
14.
STUDY ON MIXIS POTENTIAL OF ROTIFER RESTING EGGS（ BRACHIONUS PLICATILIS ） WITH DIFFERENT COLLECTION TIMES AND DIFFERENT PRESERVATION PERIODS 总被引：1，自引：0，他引：1
The present study investigated the possible changes in the mixis potential of rotifer resting eggs produced by a single stock of Brachionus plicatilis and collected and preserved annually from 1985 - 1998. Several clones derived from each batch of resting eggs were cultured under the same conditions for 21 days. The percentage of clones appearing resting eggs and the average yield of resting eggs produced from each clone were recorded and statistically analyzed to find the differences between the mixis potential of those resting egg batches. Results showed that different batches of resting eggs had different mictic levels among their descendent clones; but no regular relationship was found between the mixis potential of resting eggs and their collection times/preservation periods. Several internal and external factors that might affect the mixis potential of resting eggs were discussed. 相似文献
15.
The seasonal dynamics of a crustacean zooplankton community in Erhai Lake was investigated from May 2010 to April 2011. In total, 11 species were recorded, including six （6 genera） cladoceran and five （5 genera） copepod species. The crustacean zooplankton densities ranged from 24.3 to 155.4 ind./L. In winter and spring, the large-bodied cladoceran Daphnia galeata dominated the crustacean plankton community. In summer and autumn, when the colonial or filamentous algae dominated the phytoplankton communities, the small-bodied species （e.g. Bosminafatalis, Ceriodaphnia quadrangular, and Mesocyclops leuckarti） replaced the large-bodied ones. One-way ANOVA and redundancy analysis revealed that community structure was dependent upon total nitrogen, total phosphorus, water temperature, transparency, and the biomass of small algae. The variation in both phytoplankton structure and environmental variables were important factors in the seasonal succession of crustacean zooplankton structure in Erhai Lake. 相似文献
16.
【目的】研究雷州半岛东部近岸海域大型底栖经济甲壳动物的群落结构及其影响因素,为甲壳类资源评估与合理利用提供参考依据。【方法】于2016年4月至2017年2月按季度在该海域开展4个航次的渔业资源底拖网调查,采集经济甲壳动物样品,并进行分类鉴定,同时采集环境数据。采用聚类分析和冗余分析(RDA),评价该海域不同季节甲壳动物群落结构特征及其与环境因子的关系。【结果】共有甲壳动物98种,隶属2目24科43属;全年优势种有变态蟳(Charybdis variegata)、哈氏仿对虾(Parapenaeopsis hardwickii)和须赤虾(Metapenaeopsis barbata)等10种;各季节丰富度指数(D)、多样性指数(H′)、均匀度指数(J′)均以夏季最高,冬、春季次之,秋季最低;各季节均可划分为两个群落(Anosim test:0.579相似文献
17.
南海海域三疣梭子蟹的幼体培育 总被引：1，自引：1，他引：0
幼体期Z1和Z2投喂扁藻和轮虫,Z2后期开始以轮虫和卤虫无节幼体混合投喂,Z3后用卤虫无节幼体投喂,大眼幼体用不同饵料培育,进行南海海域三疣梭子蟹幼体培育,结果表明:溞状幼体平均成活率为15.3%;Z2变态为Z3、Z4变态为M为溞状幼体培育的敏感期,幼体的阶段成活率较低;以卤虫无节幼体、冰冻卤虫成虫、活卤虫成虫为饵料,均能使培育大眼幼体至幼蟹,其中活卤虫成虫投喂、加防残网片培育效果最好,成活率达80%。 相似文献
18.
Temperature treatment to inhibit extrusion of the polar body of the egg was first used on a lower crustacean,Artemia salina (Gross, 1932), and then was used for inducing triploids of amphibian (Frankhauser and Griffiths, 1939), fish (Svardson, 1945),
and mammal (Beatly and Fishchberg, 1949).
So far, induction of triploidy has been extensively used to obtain sterile or quick-growth individuals in fish (Swarup, 1956;
Lincoln, and Scott, 1983 and Thorgaard, 1986) and mollusk (Stanley et al., 1984), but similar work has not been reported on
crab, a higher crustancean. 相似文献
19.
Floodplains are important and distinctive ecosystems around the world, and the recruitment of ichthyoplankton from river to floodplain lakes is crucial to maintain this unique ecosystem. However,this process has not been well documented. In this study, ichthyoplankton were sampled to investigate the details of ichthyoplankton recruitment from the Changjiang(Yangtze) River to the Dongting Lake via a floodway channel, the Songzi River, from May to July in 2013 and 2014. During the study period, 41 species of eggs and larvae were sampled. Among the samples, 16 were river-lake migratory species(RL), representing23.5% of the species in the Dongting Lake. In 2013, an estimated 130 million eggs and 3 180 million larvae drifted through the sampling section, and in 2014, an estimated 1 060 million eggs and 1 040 million larvae drifted through the sampling section. The amount of eggs and larvae of RL reached 3 210 million in 2013 and 1 850 million in 2014, respectively. These results demonstrated the importance of ichthyoplankton recruitment from the river to the lake, as species diversity will decrease sharply without this recruitment.Canonical correspondence analysis(CCA) showed that water temperature and water flow are the two most important factors influencing the spawning activities of fish. To maintain the high fish diversity in the Changjiang floodplain, we suggest to irrigate the channel to increase water discharge and increase the transport of ichthyoplankton from the Changjiang mainstream into the Dongting Lake. 相似文献