苏北浅滩养殖筏架附生绿藻入海过程在黄海绿潮形成中的作用   总被引：3，自引：0，他引：3  

张清春  孔凡洲  颜天  于仁成  胡晓坤  苗辉  周名江 《海洋与湖沼》2018,49(5):1014-1020

本研究采用现场定量观测为主的研究方法,在2017年5月期间对苏北浅滩竹根沙收紫菜养殖筏架作业过程进行跟踪调查;对养殖筏架绠绳附生绿藻自然脱落和收筏架作业过程人为刮落附生绿藻,以及收筏架作业前后入海的漂浮绿藻生物量进行定量观测。结果表明:筏架绳附生绿藻自然脱落率低,为3.58%±0.78%;收筏架作业过程中绠绳上刮落绿藻生物量为(12±3)kg湿重/根,由此估算2017年整个苏北浅滩刮落的生物量估算可达到万吨湿重;收筏架作业后海域漂浮绿藻生物量是作业前的7.6倍。研究结果进一步明确了收筏架作业过程中人为刮落绿藻是目前筏架附生绿藻最主要的入海方式。刮落绿藻是海水中漂浮绿藻的主要来源,其生物量对南黄海绿潮的规模大小有重要的影响。研究结果为绿潮防控措施的制定和实施提供科学依据。  相似文献   

东海PN断面透明胞外聚合颗粒物分布特征及来源研究     

舒逸  张桂成  孙军 《海洋学报》2018,40(8):110-119

透明胞外聚合颗粒物（TEP）是凝聚网的重要组成部分甚至核心，在微尺度范围上形成了水环境结构的重要梯度，对于元素地球化学生物循环、碳沉降以及食物网有着举足轻重的作用。本文研究了东海典型断面PN透明胞外聚合颗粒物的分布特征及来源。结果表明:东海典型断面PN透明胞外聚合颗粒物含量介于28~376 μg Xeq./L之间，平均值为（115±67）μg Xeq./L；呈现出明显的夏季 > 冬季 > 秋季 > 春季的季节变化特征以及近岸 > 外海和底层 > 表层的分布趋势。通过对比透明胞外聚合颗粒物分布趋势和硅藻、甲藻分布趋势以及统计分析得出，东海典型断面PN透明胞外聚合颗粒物主要来源于硅藻，甲藻贡献不大；而外海TEP的来源可能主要由超微型浮游植物贡献。  相似文献   

海洋功能区划与海洋生态红线关系探讨          下载免费PDF全文

高月鑫  曾江宁  黄伟  陈全震  寿鹿  徐晓群 《海洋开发与管理》2018,35(1):33-39

海洋生态红线制度是我国"五位一体"文明建设的具体要求。为进一步在自然科学与人文科学的联结点上探求深入开展生态红线工作的可能性,文章对比了实施多年的海洋功能区划与历史新阶段提出的海洋生态保护红线的概念和内涵,剖析了两者之间的区别与联系,指出海洋功能区划与海洋生态红线区划在法律地位和管控制度等方面具有一致性,在划分目标、空间管理及划分方法上具有差异性,海洋功能区划以"使用"为主,海洋生态红线以"保护"引领。在此基础上,建议未来海洋生态红线工作的开展可从海洋功能区划借鉴经验,建立完善的管控评估制度,确立生态保护红线的优先地位,处理好海洋功能区划与海洋生态红线区划的关系。同时,海洋生态红线区划应以维持海洋生态系统结构稳定和提高海洋生态系统服务功能为目标,将区域资源环境承载力评估作为一项参考指标,限制低承载区的开发利用,保证海洋生态环境健康可持续发展。  相似文献   

Mesozooplankton spatial distribution and community structure in the South Adriatic Sea during two winters (2015, 2016)          下载免费PDF全文

Marijana Hure  Hrvoje Mihanović  Davor Lučić  Zrinka Ljubešić  Petar Kružić 《Marine Ecology》2018,39(1)

Whereas the data on mesozooplankton in the epipelagic offshore Mediterranean Sea are extensive, less information is available about plankton in the deeper layers. The present study aims to describe the vertical and horizontal structure and distribution of mesozooplankton species and their associations down to 1,200 m in the water of the Southern Adriatic Sea. Zooplankton were sampled using a Nansen net of 200‐μm mesh size during two cruises in the winters of 2015 and 2016, extending from the coast to the open sea. In total, 203 zooplankton taxa were identified. The community was dominated by copepods, representing between 67% and 91% of the total abundance. The highest total densities were recorded in the upper layers where a high proportion (up to 36%) of appendicularians was also observed in the first sampled year. Five groups of samples were determined based on their community structure. In 2015 communities were distinct between the 0 and 50 m layer and the underlying one (50–100 m), whereas in 2016 epipelagic waters were inhabited by a more uniform mesozooplankton community. The mesopelagic and deep‐water fauna, especially copepods, showed a relatively stable composition in both sampling years Overall, our study confirms the oligotrophic character of the Southern Adriatic, with occasional density outbreaks of appendicularians under favourable conditions.  相似文献   

A Middle Palaeolithic site in the southern North Sea: investigating the archaeology and palaeogeography of Area 240          下载免费PDF全文

L. TIZZARD  A. R. BICKET  J. BENJAMIN  D. DE LOECKER 《第四纪科学杂志》2014,29(7):698-710

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Tectonostratigraphic framework and depositional history of the deepwater Ulleung Basin,East Sea/Sea of Japan     

Kyoung-Jin Kim  Dong-Geun Yoo  Nyeon-Keon Kang  Bo-Yeon Yi 《Basin Research》2020,32(4):613-635

The Ulleung Basin, East Sea/Japan Sea, is a Neogene back-arc basin and occupies a tectonically crucial zone under the influence of relative motions between Eurasian, Pacific and Philippine Sea plates. However, the link between tectonics and sedimentation remains poorly understood in the back-arc Ulleung Basin, as it does in many other back-arc basins as well, because of a paucity of seismic data and controversy over the tectonic history of the basin. This paper presents an integrated tectonostratigraphic and sedimentary evolution in the deepwater Ulleung Basin using 2D multichannel seismic reflection data. The sedimentary succession within the deepwater Ulleung Basin is divided into four second-order seismic megasequences (MS1 to MS4). Detailed seismic stratigraphy interpretation of the four megasequences suggests the depositional history of the deepwater Ulleung Basin occurred in four stages, controlled by tectonic movement, volcanism, and sea-level fluctuations. In Stage 1 (late Oligocene through early Miocene), syn-rift sediment supplied to the basin was restricted to the southern base-of-slope, whereas the northern distal part of the basin was dominated by volcanic sills and lava flows derived from initial rifting-related volcanism. In Stage 2 (late early Miocene through middle Miocene), volcanic extrusion occurred through post-rift, chain volcanism in the earliest time, followed by hemipelagic and turbidite sedimentation in a quiescent open marine setting. In Stage 3 (late middle Miocene through late Miocene), compressional activity was predominant throughout the Ulleung Basin, resulting in regional uplift and sub-aerial erosion/denudation of the southern shelf of the basin, which provided enormous volumes of sediment into the basin through mass transport processes. In Stage 4 (early Pliocene through present), although the degree of tectonic stress decreased significantly, mass movement was still generated by sea-level fluctuations as well as compressional tectonic movement, resulting in stacked mass transport deposits along the southern basin margin. We propose a new depositional history model for the deepwater Ulleung Basin and provide a window into understanding how tectonic, volcanic and eustatic interactions control sedimentation in back-arc basins.  相似文献   

全球气候变化下南海诸岛保护优先区识别分析   总被引：3，自引：1，他引：2  

左秀玲  苏奋振  张宇  吴文周  吴迪 《地理学报》2020,75(3):647-661

全球变化下,珊瑚礁保护区是保护生物多样性、增强珊瑚礁对气候变暖抵抗力的有效方式,而维持珊瑚礁弹性是其核心内容。针对珊瑚礁最具有威胁性的热压力因子,基于南海1982—2009年卫星观测海表面温度（SST）数据和CMIP5加拿大地球系统模式CanESM2模型预估的2006—2100年南海SST数据构建热压力强度模型,从维持珊瑚礁弹性的角度识别IPCC RCP 4.5和RCP 8.5情景下南海诸岛保护优先区。结果表明：RCP 4.5和RCP 8.5情景下13%左右的南海诸岛珊瑚礁识别为保护优先区。根据热压力强度与珊瑚抵抗力及避难所关系,西沙群岛七连屿和晋卿岛近年观测与未来预估的热压力强度均比较低,在保障其服务功能的基础上建议实施完全保护;东沙群岛东沙环礁和中沙环礁排洪滩近年观测急性热压力强度较高但未来预估热压力强度较低,建议实施50%禁止利用保护;中沙群岛黄岩岛近年观测和未来预估的急性热压力强度均比较低,建议实施50%多用途保护。南沙群岛有14%左右的珊瑚礁识别为保护优先区,根据其热压力强度可实施30%~100%禁止利用保护或30%~50%多用途保护。RCP 4.5和RCP 8.5情景下的南海诸岛保护优先区及保护对策,可为维持珊瑚礁生态弹性及应对全球气候变化提供重要的参考价值。  相似文献   

池塘养殖刺参安全度夏技术研究          下载免费PDF全文

刘锡胤  周文江  贺加贝  张晓明  陈伟  黄华  张岚 《海洋开发与管理》2018,35(2):103-108

文章概述夏季池塘养殖刺参死亡症状和灾情特点,分析刺参死亡原因主要包括池水盐度骤降、池水温度升高、池水pH值下降、池水分层、有机污染和刺参自身原因。在此基础上,提出池塘养殖刺参安全度夏的技术措施,主要包括科学合理选择养殖地址、规范池塘建设、做好度夏前准备工作、水质管理、及时清除水草和大型藻类、采取降温措施以及补充营养等,涉及大量具体操作方法,具有科学性和实用性。  相似文献   

基于多源数据的山东省围填海造地特点及发展趋势研究          下载免费PDF全文

安国强 《海洋开发与管理》2018,35(3):15-20

文章基于文献资料分析、官方数据汇总、国产高分辨率资源卫星遥感影像信息提取以及发展趋势研判等方法,对改革开放以来山东省全海域范围内围填海造地的历史发展、现状特征、发展趋势及其对生态环境的影响进行了分析和总结,并提出相关的政策建议。研究表明:改革开放以来,山东省围填海造地累计已超过4.58万hm~2。21世纪以来围填海造地进入快速增长时期,尤其是2010年以来,全省围填海造地又掀起了一次新的热潮,其面积和速度都远远超过了历史水平。鉴于围填海造地对环境和生态的巨大影响,文章提出了加强管理、严格环境影响评价、引入生态环境补偿机制以及建立分级填海评估制度和年度监测机制等建议。  相似文献   

卡里马塔海峡水体交换的季节变化   总被引：2，自引：0，他引：2  

王研  徐腾飞  李淑江  Susanto R. Dwi  Agustiadi Teguh  Trenggono Mukti  谭伟  魏泽勋 《海洋学报(英文版)》2019,38(4):47-57

Four trawl-resistant bottom mounts, with acoustic Doppler current profilers(ADCPs) embedded, were deployed in the Karimata Strait from November 2008 to June 2015 as part of the South China Sea-Indonesian Seas Transport/Exchange and Impact on Seasonal Fish Migration(SITE) Program, to estimate the volume and property transport between the South China Sea and Indonesian seas via the strait. The observed current data reveal that the volume transport through the Karimata Strait exhibits significant seasonal variation. The winteraveraged(from December to February) transport is –1.99 Sv(1 Sv=1×10~6 m~3/s), while in the boreal summer(from June to August), the average transport is 0.69 Sv. Moreover, the average transport from January 2009 to December2014 is –0.74 Sv(the positive/negative value indicates northward/southward transport). May and September are the transition period. In May, the currents in the Karimata Strait turn northward, consistent with the local monsoon. In September, the southeasterly trade wind is still present over the strait, driving surface water northward, whereas the bottom flow reverses direction, possibly because of the pressure gradient across the strait from north to south.  相似文献