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251.
何岚轩  杨蕴  宋健  俞烜 《海洋科学》2024,48(1):85-97
随着全球气候变暖,风暴潮在沿海地区的频率和强度均可能增长,由此引发的海水垂向入侵可能会造成大面积的含水层淡水咸化。同时,由人类活动引起的沿海虾塘咸水养殖规模日益增长,由此引发的咸水垂向入侵可能会导致沿海地区地下水水质及生态环境的恶化。虽然已有一部分学者在海水(咸水)垂向入侵的研究中取得了成果,但由于海水(咸水)垂向入侵过程复杂,其对地下水咸化及恢复规律依然有待深入研究。文章阐述了海水垂向入侵的危害及前人的研究办法,总结了他们的研究成果并得出了海水垂向入侵的影响因子,指出了洪水和养殖活动对沿海地区含水层的威胁。得出的结果如下:研究海水垂向入侵常用的方法包括室内试验和数值模拟;海水垂向入侵主要与地形地貌、含水层性质和水文气象条件有关;虾塘养殖等人类活动可能会成为垂向咸水入侵的潜在来源。建议未来在海水垂向入侵研究中将多种现场观测实验方法结合起来。数值模拟应注重与现场观测实验数据相互验证,模型简化的方式有必要仔细考虑。虾塘养殖等人类活动可能造成的垂向咸水入侵问题应更多地受到关注。  相似文献   
252.
Abstract. The role of larval settlement, post-settlement mortality and competition with a red algae in determining the patterns of abundance and distribution of the spirorbid tube worm Neodexiospira brasiliensis (Grube) (Polychaeta: Spirorbidae) on leaves of three seagrass species: Zostera marina Linnaeus, Zostera asiatica Miki and Phyllospadix iwatensis Makino were examined in Aininkap, Akkeshi Bay, Akkeshi, Hokkaido, Japan. Field collections of seagrass shoots were made at about 1-week intervals. The density of newly settled larvae (< 0.3 mm in tube diameter) increased significantly on Z. asiatica and P. iwatensis , but not on Z. marina during the sampling period. It was highest on Z. asiatica among the three seagrass species, followed by P. iwatensis and Z. marina . Newly settled larvae occurred more on the basal part of younger leaves of each seagrass species. Mortality tended to be high on Z. marina , followed by Z. asiatica and P. iwatensis , although the differences were not great. Size-specific mortality showed the existence of high mortality in early post-settlement stages on Z. asiatica and P. iwatenisis . Relatively high mortality was also suffered by individuals with a tube diameter over 1.5 mm. Growth in tube diameter of N. brasiliensis was slower on P. iwatensis than on the other two seagrasses. The effect of a calcareous red algae on larval settlement was investigated with removal experiments; however, no effect of red algae was detected. Patterns in the distribution and abundance of N. brasiliensis on leaves of three seagrass species resulted from the heterogeneity of larval settlement rather than from post-settlement mortality or competition with red algae. Different densities of larval settlement among the three seagrass species or on a leaf are likely to relate to larval behaviour, such as negative phototaxis.  相似文献   
253.
针对对虾养殖过程水处理的研究现状和瓶颈问题,文章综述了国际和国内重要的水处理管理理念与策略,主要包括:养殖用水“减法”管理理念、投入品“减法”管理理念、基于微生物的水处理策略和基于不同营养级的生物水处理策略等。较全面地探讨了养殖节水、生态调水、精准投喂、补偿生长、生物饵料、生物过滤器、水动力等对于水处理的重要性。并建议建立基于对虾福利生物学的水处理评价体系,联合生物行为变化、生态生理指标、水体理化指标进行综合评价。该综述期望为对虾产业和水产养殖的可持续发展提供新思路和可行路径。  相似文献   
254.
即墨养虾场虾病暴发前期底质中叶绿素的变化   总被引:3,自引:0,他引:3  
本文在测定养虾池底质中叶绿素的变化,比较了在30℃,40℃,50℃,60条件下烘干与不烘干底质样品叶绿素a的测定结果。表明随烘干温度上升测定结果的偏差增大,各温度梯度偏差分别为30℃13.24%、40℃34.93%、50℃57.19%、60℃76.03%。而不经烘干处理的样品结果偏差为1.23%。运用不烘干法对5、6、7月份养虾池底质叶绿素a及脱镁叶绿素进行了测定。结果表明在虾暴发前虾池底质中叶绿  相似文献   
255.
对红虾虾头和虾肉中的脂肪进行了提取和测定。脂肪甲酯化后,采用50m×0.35mmi.d.PEG-20M玻璃毛细管柱,FID检测器,并结合GCLMS进行了脂肪酸分析。结果表明,虾头中脂肪含量达10.8×10-2,其不饱和脂肪酸68.8×10-2,EPA+DHA占24.1×10-2;虾肉中脂肪仅为3.9×10-2,其不饱和脂肪酸69.8×10-2,EPA+DHA为27.3×10-2。  相似文献   
256.
A 13-day feeding trial was carried out to evaluate the effectiveness of a microbound diet for rearing the larvae of Chinese shrimp Fenneropenaeus chinensis in comparison with the live foods that consist of Isochrysis galbana, Chlorella vulgaris, Tetraselrnis chuii, rotifer (Brachionus plicatilis) and Arternia sp. Larvae of 0 to 13d post-hatch (dph) were reared in a temperature-controlled semi-open culture system and stocked at a density of 100 larvae L^-1 in tanks, each containing 50 L sterilized seawater with salinity 30-32. Larvae were manually fed either the live foods or the microbound diet 6 times per day. At 13 dph, the growth of the larvae fed on the microbound diet was approximately 84% of that fed on the live foods. The survival rate of the larvae fed on the microbound diet was 44.29% at 13dph, which was not significantly different from that of larvae fed on live foods (63.55%). The body length and development index (DI) of the larvae fed on the microbound diet were always lower than those of larvae fed on live foods. However, the differences reached significant levels only at 11 and 13 dph (P〈 0.05). The mean dry weight loss of the microbound diet was 9.2% after 90 min immersion in seawater, indicating that this diet has a good water stability. The microbound diet contains 52.23% crude protein and 10.27% lipid and is easy to prepare. These characteristics of the diet suggest good potentials for its successful use in the larviculture of other penaeid and fish species.  相似文献   
257.
对虾细胞培养及对虾病毒体外培养研究进展   总被引:1,自引:0,他引:1  
随着对虾病毒病研究的不断深入迫切需要建立连续性的对虾细胞系来揭示对虾病毒致病机理等关键问题。文章介绍了用于细胞培养的对虾种类、组织。用于细胞培养的对虾种类包括中国明对虾Fenneropenaeuschinensis、斑节对虾Penaeusmonodon、日本囊对虾Marsupenaeusjaponicus、凡纳滨对虾Litopenaeusvannamei等。用于培养的对虾组织包括甲壳下表皮、心脏、肝胰腺、鳃、肠上皮、淋巴、血淋巴、卵巢、神经、肌肉、造血组织等。同时重点介绍了离散细胞的方法和培养的方式,温度、pH、渗透压的选择,目前对虾细胞培养所用的培养基及促生长添加物,以及如何控制污染。探讨了目前在对虾细胞培养及建系中存在的问题和可能的解决途径,为对虾与其它甲壳类动物细胞培养及细胞系的建立提供参考。此外还介绍了对虾病毒体外培养的研究现状并探讨了可能的解决方案。  相似文献   
258.
The feeding habit of Austrolethops wardi (Gobiidae) in the seagrass beds of Barrang Lompo and Bone Batang Island in the Spermonde Archipelago, South West Sulawesi, Indonesia, was investigated through gut content analysis. The feeding preferences of this species are very similar on both islands: A. wardi, a burrow associate of Neaxius acanthus, was found to feed almost exclusively on seagrass (which was found in 100% of the investigated stomachs and made up >94% of food items). However, seagrass epiphytes (<5% of food items) and animal food (<1% of food items) occurred in the guts as well, the latter predominantly in terms of copepods and to a lesser degree in other small invertebrates. These results indicate that animal food is of little importance for A. wardi. Some specimens even contained no parts of animal food.  相似文献   
259.
Stable isotope methods can be used to determine the food sources and prey items of aquatic organisms accurately and reliably. This study examined the relative contribution of artificial foods (the formulated feed and Artemia) and natural foods to shrimp growth in an intensive Fenneropenaeus chinensis pond by using carbon and nitrogen stable isotopes. The results showed that the nutrition utilization efficiency of the harvested shrimp was low, only 33.18% of feed nitrogen and 21.73% of feed carbon being converted to shrimp flesh. Our stable isotope results showed that the shrimp obtained nutrition for maximum growth from artificial foods, whose contribution was 93.5%, with the remaining attributed to the natural foods. However, there was 0.94 t harvested shrimp derived from natural foods (the rest of 13.56 t harvested shrimp derived from artificial foods) in 1ha intensive pond with a shrimp production of 14.50 t ha−1. Therefore, unit area shrimp production can be increased by increasing the contribution proportion of natural foods in intensive shrimp farming.  相似文献   
260.
为探究乐清湾虾类群落结构的形成和影响因素,作者于2020年9月在该海域开展海洋生态系统综合调查,运用相对重要性指数、生态位宽度、生态位重叠等生态指标,结合非度量多维标度法(MDS)和冗余分析(RDA)对群落结构、生态位的重叠和分化进行分析。结果表明:秋季研究海域共有虾类16种,隶属于6科、10属;哈氏仿对虾(Parapenaeopsis hardwickii)和中华管鞭虾(Solenocera crassicornis)为优势种,周氏新对虾(Metapenaeusjoyneri)、脊尾白虾(Exopalaemoncarinicauda)和刀额新对虾(Metapenaeus ensis)为常见种;哈氏仿对虾、中华管鞭虾、周氏新对虾和脊尾白虾属于中等生态位种,其余均为窄生态位种;红条鞭腕虾(Lysmatavittata)与太平洋长臂虾(Palaemonpacificus)的重叠值最高,中国毛虾(Acetes chinensis)、葛氏长臂虾(Palaemon gravieri)和细指长臂虾(Palaemon tenuidactylus)等与其他种类重叠值较低;影响该海域秋季虾类分布的主要环...  相似文献   
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