解读瓶鼻海豚

提起瓶鼻海豚(以下简称海豚)，常听朋友们说：“这个我知道，不就是在海洋馆见到的那种最可爱、最聪明的鱼吗!”海豚的确是生活在大海中的，可如果你把它理解成鱼可就大错特错了。鱼的全身覆盖有鳞片、尾鳍是     

深海贝莱斯芽孢杆菌DH82的抑菌活性物质初步分离纯化及其抑菌谱检测

贝莱斯芽孢杆菌(Bacillus velezensis) DH82发酵上清液经最佳硫酸铵饱和度(70%)沉淀、透析获得粗蛋白,粗蛋白经Sephadex G-75柱层析的色谱条件为柱1. 6 cm×50. 0 cm;上样量为5 mL;洗脱液为超纯水,流速2 mL/min;检测波长280 nm,获得两个具有抑菌活性的峰蛋白PrⅠ和PrⅡ。两个峰蛋白经抑菌谱检测,发现对常见水产指示病原细菌包括迟缓爱德华氏菌(Edwardsiella tarda)、嗜水气单胞菌(Aeromonas hydrophila)、坎氏弧菌(Vibrio campbellii)、溶藻弧菌(Vibrio alginolyticus)、哈维氏弧菌(Vibrio harveyi)、无乳链球菌(Streptococcus agalactiae)和金黄色葡萄球菌(Staphylococcus aureus)都具有较好抑菌活性,表明深海贝莱斯芽孢杆菌DH82产生的抑菌活性物质对水产病原细菌的抑菌谱较广,其中峰蛋白PrⅡ对指示植物病原真菌水贼镰刀菌(Fusarium equisetum)也具有较好抑菌作用。进一步对峰蛋白进行最小抑菌浓度(MIC)检验,发现其对迟缓爱德华氏菌和溶藻弧菌的MIC都较低(为7. 16μg/mL)。以上研究结果表明,深海贝莱斯芽孢杆菌DH82具有较宽的抑菌谱及较强的抑菌活性,预示该菌株在常见水产细菌性及个别植物真菌性病害防治上具有较好的开发利用价值。     

Abundance of the Indo-Pacific bottlenose dolphin Tursiops aduncus off south-west Mauritius

The abundance of Indo-Pacific bottlenose dolphins Tursiops aduncus off the south-west coast of Mauritius was estimated using capture-mark-recapture modelling. Over the past two decades this population has been subjected to ongoing anthropogenic disturbance in the form of extensive coastal development. Furthermore, daily dolphin tourism, which started in 1998, has rapidly increased in intensity. Identification photographs were collected between April 2008 and June 2010 from dolphins occurring along a 30 km length of coast where a dolphin tourism industry is concentrated. A total of 137 groups were encountered over 229 survey days. Over 5 000 photographs were taken, from which 35 individuals were considered to be sufficiently distinctively marked to use in mark-recapture analyses. The majority (85.7%) were seen more than once and resighting frequencies indicated a resident population. Three newborn calves were recorded during the study. Open population models produced abundance estimates of <100 individuals in the population. These results will be used to make recommendations for the conservation and management of this small, resident population, which is a valuable economic resource for the island but is currently under threat from high levels of human activity.     

Movement patterns of coastal bottlenose dolphins in the presence of a fast-flowing,prevailing current: shore-based observations at Cape Vidal,South Africa

The presence and movement of Indo-Pacific bottlenose dolphins Tursiops aduncus were investigated using shore-based observations made during a humpback whale Megaptera novaeangliae migration survey at Cape Vidal, South Africa, undertaken between June and October 1988–1991. Occurrence was analysed as counts of dolphin sightings per hour within a generalised estimating equation framework. Bottlenose dolphin sightings decreased throughout the daily survey period, and there was a small seasonal peak in sightings during August. Data on movement trajectory were collected using a theodolite for 60% of the groups of dolphins sighted. Most groups were observed travelling in a northerly direction, with few groups recorded moving south. A generalised linear model indicated that northward-travelling dolphins were located closer to shore, travelled at higher speeds, and occurred in bigger groups under low-tide conditions, than those seen moving in a southerly direction. The southward-flowing Agulhas Current is close to shore at Cape Vidal, where the continental shelf is particularly narrow. We suggest that bottlenose dolphins in this area have adopted a specific movement regime to cope with the consistent fast-flowing currents that dominate their environment at Cape Vidal.     

莆田近岸海域海带烂孔病起因的初步研究

2019年3月莆田近岸海域海带尾部烂孔后逐渐向根部蔓延,孔洞相连后海带脱落,时空规律为先南后北逐渐发病,共涉及养殖面积约7 km2,给莆田近岸海带养殖带来了较大的损失。初步研究分析了海带大规模烂孔的原因,主要结果如下:海区温度异常升高,盐度持续较低,连续阴天光照不足,环境变化超出了细胞生理承受能力从而造成海带烂孔。此次诊断,对渔业生产及海洋环境监测结果在渔业上的应用均具有一定的现实意义。     

西沙赵述岛海域珊瑚礁生态修复效果的初步评估

珊瑚恢复是一个协助退化、受损的珊瑚礁生态系统恢复的过程.近10 a来,西沙珊瑚礁生态系统不断退化,至2009年珊瑚覆盖率已下降至不足10%.针对西沙群岛珊瑚礁生态系统的退化状况,2011年12月于西沙赵述岛海域投放人工礁基并开展珊瑚移植实验,比较了人工修复区和自然恢复区1a后的修复效果.结果显示,投放礁基且进行珊瑚移植的区域,移植珊瑚的存活率不到10%;投放礁基但未进行珊瑚移植的区域,珊瑚补充量高达6~7 ind/m2;自然恢复区其珊瑚覆盖率提高了19.4%.依据珊瑚礁生态修复效果评估方法,人工修复且进行移植珊瑚的区域的生物修复权重值为27.5,人工修复但未移植珊瑚区及自然恢复区的生物修复权重值为39.3,珊瑚修复生物指标为亚健康.我们的结果表明,在健康、有良好珊瑚幼虫补充的珊瑚礁生态系统中,珊瑚礁群落可以自行恢复,其恢复只是一个时间的问题;而在缺少珊瑚幼虫附着基底的区域,通过人为增加一些附着基底,可加速其恢复进程.     

无居民海岛植被恢复过程中物种多样性及土壤特征初步研究

2016年4月对厦门无居民海岛猴屿开展了植被和土壤调查,采用全岛调查的方法查清全岛植物种类及生长状况,采用样方调查的方法分析比较人工恢复林和次生林物种多样性和土壤肥力特征,以期为无居民海岛生态修复提供借鉴.结果表明,全岛共有乔木5科5属6种,灌木有10科12属13种,草本植物有21科39属40种.由于被海包围、面积狭小、地形简单,物种传播速度慢,猴屿生物多样性较低,猴屿人工恢复林物种多样性与次生林差异不显著.人工恢复林土壤肥力显著低于次生林,植物生长及其产生的凋落物可以促进土壤肥力的改善.海岛普遍风大、缺水,植被恢复应选用适应海岛环境能力强的物种.猴屿植被破坏导致生态位缺失,进而造成马缨丹生物入侵,影响海岛生态系统稳定性.     

一种甲壳动物血细胞分化因子性质的初步分析

血细胞是甲壳动物的免疫细胞,负责抵御和清除入侵的病原。虽然血细胞在甲壳动物的整个生命周期中都需要不断更新,但人们对甲壳动物造血机制的了解却十分有限。前期研究发现利用红螯螯虾的肌肉提取液可以诱导体外培养的造血组织细胞定向分化为颗粒细胞,但其中起到诱导分化作用的因子尚未明确。本研究对该未知血细胞分化因子的基本性质进行了分析。首先,我们制备了红螯螯虾（Cherax quadricarinatus）、中华绒螯蟹(Erinocheir sinensis)、东亚飞蝗(Locusta migratoria manilensis)、红石斑鱼(Epinephelus goreensis)、凡纳滨对虾(Litopenaeus vannamei)和疣荔枝螺(Reishia clavigera)的肌肉提取液,测试其诱导螯虾造血组织细胞分化的能力。结果表明,以上各种动物的肌肉提取液均可诱导原代培养的螯虾造血组织细胞向颗粒细胞分化,说明该血细胞分化因子普遍存在于这些动物的肌肉组织中。进一步我们以螯虾肌肉提取液为实验对象,分析了血细胞分化因子的热稳定性、溶解性、带电性、对蛋白酶的耐受性以及分子量大小。结果发现该血细胞分化因子易溶于甲醇,呈电中性,具有良好的热稳定性,且可耐受蛋白酶处理,分子量小于1 kDa。因此,螯虾肌肉提取液中可诱导造血组织细胞分化为颗粒细胞的血细胞分化因子是一种广泛存在的小分子类物质。本研究结果有助于后续对该因子的分离纯化和鉴定。     

Genetic diversity and population structure of the franciscana dolphin,Pontoporia blainvillei,in Southern Buenos Aires,Argentina

The franciscana dolphin, Pontoporia blainvillei, is endemic to the coastal waters of the southwestern Atlantic Ocean and the most endangered dolphin in the area. Four Franciscana Management Areas (FMAs) are currently recognised; however, results of genetic studies suggest the requirement for additional FMAs and highlight the need for more detailed studies in the southern extreme of the species distribution. With this aim, we studied the genetic diversity and population structure of the species analysing an mtDNA control region fragment (434?bp) in 44 individuals collected in four sampling sites located in Southern Buenos Aires. Haplotype diversity (H?=?0.75?±?0.05) was mostly higher than the observed in endangered or near threatened odontocetes. Population structure analyses suggest that three different genetic populations should be recognised within FMA IV: Northern, Eastern and Southern Buenos Aires. Altogether, these results should be taken into account in future conservation plans for the species.     

九龙江口海门岛红树林湿地大型底栖动物群落生态研究

为研究福建省九龙江口海门岛大型底栖动物的群落结构变化,于2014年11月至2015年8月对海门岛红树林区的大型底栖动物进行4个季度的调查研究,并利用PRIMER软件进行群落物种多样性单变量分析、群落聚类分析(Cluster)、多维尺度排序(MDS)分析和丰度/生物量曲线(ABC)分析.结果表明:九龙江口海门岛红树林区获得大型底栖动物共计112种,年平均生物量为77. 58 g/m2,年平均栖息密度为991. 0 ind/m2. Shannon-Wiener多样性指数(H')、丰富度指数(d)和均匀度指数(J')分别为2. 42、5. 02和0. 70,其中春季生物多样性指数和均匀度指数均最低,与春季生物的繁殖有关.ABC曲线表明该区域有三分之一采样点的大型底栖动物群落受到中等到严重程度的扰动,主要集中在春季站位,这与该季节渔民滩涂养殖作业活动有关. Cluster聚类分析和MDS标序结果表明,在50%的相似性水平群落可分为6组,且不同组间显示季节差异显著.结合历史资料发现,大型底栖动物群落随环境质量的变化已出现了一定的群落演替,物种呈小型化趋势.环境因子与群落分布特征相关性较大,其中最能解释群落丰度和生物量空间分布特征的环境因子为水温、盐度和有机质含量.     

2009年春季诏安湾口海域游泳动物的种类组成和多样性

根据2009年5月单船底层拖网和定置三重刺网作业调查资料,分析研究了诏安湾口海域春季游泳动物的种类组成、生物密度指数分布及种类多样性等.结果表明：调查海域游泳动物有48种,其中鱼类为26种,占54.2%;甲壳类为16种,占33.3%;头足类为6种,占12.5%.相对重要性指数（IRI）大于500的有4种,分别为多鳞鱚（Sillago sihama）、白姑鱼（Argyrosomus argentatus）、日本蟳（Charybdis japonica）、哈氏仿对虾（Parapenaeopsis hardwickii）;种类丰富度指数范围为1.412～3.419,平均值为2.291;Shannon-wiener多样度指数范围为0.800～2.264,平均值为1.568;种类均匀度指数范围为0.411～0.836,平均值为0.659.总体来看,诏安湾口海域生物量处于较低水平,需要开展增殖放流,通过海洋牧场与人工鱼礁建设,以逐步恢复渔业资源.     

基于矢耳石重量与年龄关系对北部湾二长棘犁齿鲷年龄鉴定的研究

利用2006年7月至2008年10月北部湾商业捕捞底拖网和流刺网渔获物中采集的1 276尾北部湾二长棘犁齿鲷（Evynnis cardinalis）中1 045尾耳石完整样本,对二长棘犁齿鲷矢耳石重量与年龄关系进行了初步研究.结果显示,北部湾二长棘犁齿鲷左右矢耳石间的重量无显著差异,选用左矢耳石为研究对象;用直线、幂函数和多项式等拟合二长棘犁齿鲷各类参数间的关系,样本体长（L）与矢耳石重量（OW）呈幂函数相关：OW=2.000 0×10-6L2.143 0（R2=0.952 9,n=1 045）;北部湾二长棘犁齿鲷耳石重量与年龄（T）呈二项式关系：OW=0.002 7T2＋0.008 1T＋0.023 5（R2=0.992 5,n=1 045）,矢耳石重量与年龄呈显著的线性相关性.以此估算年龄,与从矢耳石上直接读取的年龄并无显著差异,并且,通过矢耳石重量估算年龄比体长频率法较为准确.因此,在经过适当校正后,矢耳石重量可以作为二长棘犁齿鲷年龄鉴定的有效辅助手段.