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2011年7～8月在桑沟湾楮岛南岸东部海域,利用水下调制脉冲式荧光仪(DIVING-PAM)原位测定了中国北方3种常见温带海草大叶藻、丛生大叶藻以及红纤维虾海藻的不同叶龄叶片的叶绿素荧光特性,并确定了几种海草的吸光系数(AF)和叶片叶绿素含量,计算出海草绝对电子传递速率.实验结果表明,叶龄对海草的光合活性有较大影响,同种海草的AF值和叶绿素含量都随叶龄增加而增加,叶龄小的叶片明显具有较大的最大电子传递速率(ETRmx)(大叶藻∶叶1=26.56,叶2=21.45,叶3=19.98;红纤维虾海藻叶1=22.31,叶2=19.23,叶3=17.06;丛生叶藻∶叶1=20.16,叶2=16.10;叶3=13.10).相比于丛生大叶藻和红纤维虾形藻,大叶藻具有最高的光合活性(ETRmax=22.67),这也与大叶藻在3种海草中所具有最高的初级生产力是相符合的. 相似文献
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2016年8月,现场调查并分析了山东省威海市双岛湾海域的海草资源及其生态特征,发现分布面积为442.19hm2的海草床,种类为鳗草(Zostera marina)和红纤维虾形草(Phyllospadix iwatensis) 2种。鳗草的分布面积约为434.46 hm2,占总面积的98.3%,主要分布在双岛湾中部东侧及海参池,其平均植株密度和生物量分别为(174.2±9.2) shoots/m2和(337.7±17.5) g DW/m2。红纤维虾形草的分布面积约为7.73 hm2,占总面积的1.7%,主要分布在双岛湾湾口东侧及向东约3 km的近岸礁石浅水区,呈明显的带状分布,其平均植株密度和生物量分别为(889.1±17.1)shoots/m2和(605.9±18.1) g DW/m2。双岛湾海草床平均水深约为1.6 m,鳗草草床底质坚硬,平均底质粒径约为(4.3±0.2)mm。本调查表明,双岛湾海草床受到陆源污染物排放、围海养殖和捕捞作业等人类活动的严重威胁,提出了保护双岛湾海草床的建议和对策,为我国海草床现有资源提供数据补充。 相似文献
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红螯螯虾主要病害的研究进展 总被引：3，自引：0，他引：3
红螯螯虾(Cherax quadricarinatus )属甲壳纲、十足目、长尾亚目、拟螯虾科、光壳虾属,原产地澳大利亚,具有个体大、生长快、食性杂、易饲养等养殖优势;同时,因其肉味鲜美、富含低胆固醇蛋白质,是目前世界上较名贵的淡水经济虾之一.目前,美国、拉丁美洲、西班牙、南非、东南亚、中国等许多国家引进了此虾,进行工厂化育苗及养殖.我国于1992年引入该种,先后在广东、湖北、福建、江苏、山东、北京等地试养,取得了初步的成功,并在繁殖生物学、自然水温育苗、室内工厂化育苗等方面进行了研究.但随着红螯螯虾养殖业的发展,疾病也逐渐增多.笔者就国内外近几年对红螯螯虾病害方面的研究情况进行概述. 相似文献
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为了研究不同生长时期红螯螯虾(Cherax quadricarinatus)肌肉和肝胰腺内脂肪酸和氨基酸的动态变化,选取90 d (第二性征未发育)、140 d (第二性征发育成熟)和180 d (性腺发育成熟)的红螯螯虾,分别测定其肌肉和肝胰腺内氨基酸和脂肪酸的含量。结果显示,90 d红螯螯虾肌肉中的必需氨基酸总量显著高于其他2个时期(P<0.05);而红螯螯虾肝胰腺内必需氨基酸总量和非必需氨基酸总量均随着日龄增加而逐渐下降。比较不同生长时期肌肉中脂肪酸含量发现,随着日龄增长,饱和脂肪酸(SFA)含量呈下降趋势;而单不饱和脂肪酸(MUFA)含量呈先上升后下降的变化趋势,140 d含量最高[(25.69±0.42)%];多不饱和脂肪酸(PUFA)含量呈上升的变化趋势。肝胰腺中SFA含量在 3个生长时期内无显著性差异(P>0.05),MUFA含量呈先上升后下降的变化趋势,140 d含量最高[(37.44±0.59)%],而PUFA含量变化与MUFA正好相反。营养价值评估结果显示,180 d (可上市销售)的红螯螯虾肌肉内必需氨基酸指数(49.96%)高于联合国粮农组织/世界卫生组织(FAO/WHO)评分模式(31.50%)和全鸡蛋蛋白质模式(43.10%),是较为理想的优质食物蛋白源。由上可知,在不同生长时期,肌肉和肝胰腺中的氨基酸、脂肪酸的主要消耗不同,研究结果对了解不同生长时期红螯螯虾营养需求、开发红螯螯虾配合饲料提供了参考依据。 相似文献
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海洋1号红酵母饲养日本对虾幼虾的效果 总被引：6，自引：0，他引：6
报道了在饵料中定量添加海洋 1号红酵母后 ,饲养日本对虾 (Penaeusjaponicus)幼虾的试验结果。按海洋 1号红酵母在饵料中添加量不同将试验分为 6组 ,连续投喂 14d后 ,分别测定试验和对照日本对虾幼虾的成活率、生长速度以及对环境因子的耐受力 ,比较海洋 1号红酵母在饵料中不同的添加量对日本对虾幼虾的饲养效果。试验结果表明 ,在饵料中添加海洋 1号红酵母具有提高日本对虾幼虾的成活率、促进生长和增加对环境因子耐受力的效果。 相似文献
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红螯螯虾(Cherax quadrtcarinatus)称淡水龙虾,分类上隶属于甲壳纲,十足目,拟螯虾科,光壳虾属。“红螯”为其英文名“RED CLAW”的意译。该虾体色随栖息环境变化而变化,一般为绿色或褐绿色,外形颇似海水中的龙虾,生活于淡水中故又称为淡水龙虾。该虾成虾雄性的第一对螯足的大螯外侧有一柔软膜质的鲜红、美丽的斑块,故又称为红螯螯虾。该虾原产地系澳大利亚北部,是淡水虾类中个体较大、经济价值较高的种类之一。红螯螯虾不仅个体大,而且具有食性杂,适应性强、生长快抗病力强、并具有肉质细嫩、味道鲜美、可食比率 相似文献
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红螯螯虾感染白斑综合征病毒 总被引：3，自引：1，他引：2
红螯螯虾(Cherax quadricarinatus)是澳州淡水龙虾的一种,属甲壳纲、十足目、长尾亚目、拟螯虾科、光壳虾属,原产地澳大利亚,具有个体大、生长快、食性杂、易饲养等养殖性能优势;同时,因其肉味鲜美、富含低胆固醇蛋白质,是目前世界上较名贵的淡水经济虾之一。目前,美国、拉丁美 相似文献
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为了深入了解光照对红条鞭腕虾(Lysmata vittata)亲虾抱卵情况的影响,本研究通过将正常光照组(12L∶12D)亲虾的抱卵率与全暗(黑)组进行对比,发现正常光照组红条鞭腕虾亲虾抱卵率为(95.8±3.6)%,而全暗(黑)组的抱卵率为0,正常光照组亲虾的抱卵率显著高于全暗(黑)组(P0.05),表明适宜的光照强度对红条鞭腕虾亲虾抱卵行为起到促进作用。本研究还对比分析了投喂不同生物饵料对红条鞭腕虾溞状幼体成活率和生长发育周期的影响。结果发现,投喂丰年虫(Artemia nauplii)和蒙古裸腹溞(Moina mongolica Daday)混合组的溞状幼体成活率为(38.3±2.3)%,幼体经过25～29 d全部发育成仔虾;而单一投喂丰年虫组的溞状幼体成活率为(26.8±4.9)%,幼体经过37～41 d全部发育成仔虾;混合组的溞状幼体成活率显著高于单一组(P0.05),且其幼体的生长周期也明显短于单一组,表明投喂丰年虫和蒙古裸腹溞混合饵料比只投喂丰年虫饵料更有利于幼体的存活和发育。此外,本研究还观察和详细描述了红条鞭腕幼体发育过程的形态和结构变化特征,并将它分为溞状幼体1～9期等9个不同时期,幼苗经过9期溞状幼体期后通过蜕皮最终变态为红条鞭腕虾仔虾。本研究对丰富鞭腕虾属虾类的生殖生物学理论和开展其人工繁育研究具有重要的指导意义。 相似文献
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四、淡水红螯螯虾的养殖技术。(一)虾的饲料。淡水红螯螯虾在生长繁殖中所需的营养物质包括蛋白质、糖类、脂肪、维生素、无机盐等。饵料好，虾生长快，养殖效益好。如饵料的营养成分欠佳，虾不仅生长慢，还会出现营养缺乏性疾病。饵料的品质好坏直接影响养殖效果。 相似文献
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不同光周期下红螯螯虾幼虾摄食节律的研究 总被引：1，自引：0，他引：1
在不同光周期下对红螯螯虾(Cherax quadricarinatus)幼虾的摄食节律进行了研究。结果显示:红螯螯虾具有明显的日摄食节律,24 L(持续光照)、12 L∶12 D(12 h光照:12 h黑暗)和24 D(持续黑暗)光周期下,其摄食率、摄食量和摄食发生率均在19∶00-21∶00和5∶00-7∶00出现峰值,分别为:13.01%和15.58%、20.82%和14.75%、12.77%和16.89%,属晨昏型摄食。光周期和不同时段对红鳌幼虾摄食无显著的交互作用(P>0.05)。 相似文献
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- Concern for conservation of seagrass habitat has prompted international transplantation‐style restoration efforts. A recent review of these restoration efforts has highlighted the low success associated with small‐scale restorations, yet scaling up transplantation effort may be too costly for underfunded regions. Small‐scale transplant survival can be enhanced with alleviation of two underlying issues: restoration site selection and donor site selection.
- To investigate appropriate donor source selection, donor site environmental influence on seagrass (Halodule wrightii) transplant survival was examined by transplanting donor cores from two environmentally disparate sites to a transplantation site with limited environmental uncertainties. Donor sites were chosen to represent either end of a benthic light gradient (high versus low) to elucidate seagrass resilience to transplantation stress, with respect to donor site conditions.
- After total loss of the first trial, a second trial was conducted with stabilizing mesh placed over transplants to reduce stingray bioturbation. The second trial resulted in 100% survival of high light transplants after 12 months and moderate survival (30–60%) of low light transplants for the first six months.
- At 18 months, the second trial ended after sediment burial from a hurricane. One year post‐burial, a patch of H. wrightii recovered at the high light transplant site; after six years the patch expanded to approximately 74 m2, an area 37‐fold larger than originally planted.
- Results from this transplant experiment provide evidence that donor environment plays a role in transplant resilience. The transplants sourced from high light had 47% greater leaf area per shoot, were more resistant to transplantation stress, and recovered following an extreme event relative to low light transplants. Therefore, selection of donor plants with more resilience features, a transplantation site with limited environmental uncertainties, and adaptive intervention can enhance seagrass resilience at a small planting scale.
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通过对移植2年后的大叶藻(Zosteramarina L.)的形态、生长和繁殖情况进行4个季度的观察和测量,发现在春季(3月和4月)和初夏(6月)大叶藻叶的叶绿素含量较低,而其他季节相对较高;根在冬季(12月和1月)和初春(3月)最发达;叶及叶鞘长度,叶宽和每株成体的生物量都在夏季达到最高值,而在秋季降到最低值;单株大叶藻叶生产率的最高值和最低值也分别出现在夏季和秋季;大叶藻侧生苗在冬季的萌发率最高,而夏季未观测到有侧生苗萌出。结果显示,光照影响大叶藻叶绿素的含量;水温对移植大叶藻的形态、生长和无性繁殖产生显著影响,夏季高水温对大叶藻生长的抑制作用比冬季低水温的影响更大。 相似文献
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Meryl F. Larkin Tom R. Davis David Harasti Kirsten Benkendorff Stephen D. A. Smith 《水产资源保护:海洋与淡水生态系统》2023,33(1):1-14
- The temperate soft coral Dendronephthya australis has been listed as Endangered in NSW, Australia, owing to its restricted geographic range, rapidly declining populations, and a number of escalating threats. Research to assess practical methods for aquarium cultivation of D. australis for rehabilitation of wild populations is considered a high priority.
- Previous attempts at restoration by transplanting D. australis fragments have had limited success, but identified key challenges, which included achieving attachment to substrates and identifying appropriate foods to maximize survival.
- This study presents the results of experiments promoting the attachment of cuttings (nubbins) removed from donor colonies to moveable substrates (small concrete discs). Using a balanced orthogonal experimental design, three feeding regimes were tested: live artemia, live rotifers and dry powdered zooplankton.
- Donor colony survival and growth were also monitored over a 6 month period in the field.
- An overall nubbin survival rate of 100% was achieved under all three feeding regimes. Attachment rates were similar across feeding treatments, although nubbin behavioural responses (percentage of open polyps before feeding) suggested some preference for live rotifers.
- The cutting removal process had no significant effect on donor colonies in the wild, indicating that this is a sustainable approach for restoration.
- Overall, this study substantially advances the methodology for maintaining an Endangered azooxanthellate soft coral in aquaria and provides valuable input for management programmes aimed at implementing transplantation into the wild to aid species recovery.
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E. SERVIERE-ZARAGOZA A. MAZARIEGOS-VILLARREAL T. REYNOSO-GRANADOS R. ROBLES-HERNÁNDEZ P. MONSALVO-SPENCER G. PONCE-DÍAZ A. CASTRO & A. HERNÁNDEZ-LLAMAS 《Aquaculture Nutrition》2009,15(3):241-246
The feasibility of obtaining a similar growth response from juvenile pink abalone Haliotis corrugata at a research laboratory and a hatchery, when using natural feeds was evaluated. Four macroalgae, Egregia menziesii , Eisenia arborea , Macrocystis pyrifera , Gracilaria sp., and the surfgrass Phyllospadix torreyi were used as feeds. Response patterns of abalone were very similar at both facilities in terms of final length, weight, and survival, varying from 13.0 to 15.50 mm, 0.31 to 0.52 g, and 60.0% to 78.6%, respectively. Better growth was obtained when E. menziesii , M. pyrifera , and Gracilaria sp. were offered. Poor results were obtained with surfgrass. The feed conversion ratio was determined at the laboratory and did not vary significantly, ranging from 42.3 to 199.0; although a significant inverse correlation was observed with growth rate. Growth in length and weight and survival rates varied within 1.6–20.2 μm day−1 , 0.123–1.664 mgday−1 , 0.4–0.64%day−1 , respectively. Mean growth rate in length (14.7μm day−1 ) and weight (1.18 mg day−1 ) at the hatchery were significantly higher than that obtained at the laboratory (9.4 μm day−1 and 0.77 mg day−1 ), which is most likely a consequence of more suitable water temperature at the hatchery. Mean survival rate was significantly higher at the laboratory (53.1%day−1 ) than at the hatchery (46.1%day−1 ). 相似文献
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海草是一类生活在热带至温带浅海、完全适应海洋环境的沉水被子植物的总称。海草床作为连接珊瑚礁与红树林的纽带，具有重要的生态功能与经济价值。近年来，随着人们对海草认识的不断加深，海草的有性繁殖行为逐渐受到关注，而成花诱导是海草从营养生长向生殖生长过渡的重要环节。本文综述了海草有性繁殖中成花诱因的研究进展，探讨了温度、光照、盐度等相关因子对海草成花诱导的影响，分析了海草响应外界环境刺激与内源信号启动开花途径可能集中在光周期途径、春化途径和自发途径上。建议未来海草床保护修复工作应加强对海草有性生殖行为的研究，明确不同海域海草的集中开花和结果时间，对海草床生态系统的修复与保护具有重要意义。 相似文献
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G G Thorarinsdóttir 《Aquaculture Research》1996,27(1):57-65
Annual cycles of gamete development in Mytilus edulis L. in south-west Iceland were investigated during 1986 to 1987. Histological preparations of the gonads showed that all individuals were fully mature in the beginning of June in both years and one spawning period was recorded each year at a sea temperature of 10-12oC. The main spawning took place from the middle of July to the middle of August, and from the middle of June to the end of July in 1986 and 1987, respectively. Redevelopment of the gonads after spawning was observed in February when both food availability, measured as chlorophyll a concentration, and temperature were low. Rapid gonad maturation took place during the spring phytoplankton bloom in March-April. Larval settlement was heavy on the artificial collectors used. The length of the larval period was estimated as being 4-5 weeks and peak settlement occurred in the middle of September. The size of the early plantigrades settling on the collectors during the study period indicated direct settlement of mussel larvae from the plankton onto the collectors. One year after settlement the spat averaged 24.6 mm ± 6.0 (SD) shell length and two years after settlement a market size of 50.8 mm ± 5.7 (SD) was reached. Growth was correlated with food availability, measured as chlorophyll a concentration. The growth season lasted from March to October with the greatest shell growth in late summer. The results showed that the growth of M. edulis was markedly increased by suspending the animals in a more favourable environment than that found on the natural mussel beds. 相似文献
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2016年3月6日—5月3日,在福建省漳浦县霞美镇浮头湾外海域进行三种不同结构鲍匍匐基养殖对比试验。三种鲍匍匐基分别为扣箱式(有效匍匐面积1.072 8 m2)、双层斜板式(有效匍匐面积1.993 5 m2)和传统养殖盆(有效匍匐面积0.413 3 m2),试验对象为皱纹盘鲍杂交鲍(Haliotis discus hanai)。试验结果如下:1)扣箱式鲍壳长日增长为0.131mm,日增重为0.129 g,存活率为98.44%,饲料转化率为3.38%;2)双层斜板式鲍壳长日增长为0.098 mm,日增重为0.096 g,存活率为99.38%,饲料转化率为4.29%;3)传统养殖盆式鲍壳长日增长为0.115 mm,日增重为0.103 g,存活率为98.00%,饲料转化率为5.37%。试验设施未受到湾外海况影响破坏。结果表明扣箱式鲍匍匐基整体性能较好,基于该匍匐基的鲍养殖网箱在经济型吊杆辅助作业下具有养殖效率高、抗风浪流性好、劳动强度低、所需劳动力少等优点,适合应用于湾外养殖。 相似文献