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51.
莱州湾东部滨海水域砂金分布特征 总被引:1,自引:0,他引:1
通过对莱州湾东部滨海水域地球物理和地质钻综合调查,业已查明该海区地质的构造和古地理环境特征,并发现区内砂金分布较普遍,本文从砂金分布的地貌单元,沉积物类型,砂金成因类型,物质来源,古气候,构造作用,砂金成因等诸方面,研究了该海域内砂金特征。 相似文献
52.
渤海湾盆地沙南凹陷BZ油田沙一段生屑云岩主力含油储层投产后,发现实际生产特征与初始地质认识吻合度差,部分区块可能具有增储上产的潜力。通过利用油田生产动态资料,主要包括压力、产量及PVT实验等数据,采用广义物质平衡计算法识别出A4井区滚动勘探潜力最大。在此基础上,精细刻画生屑云岩沉积期古地貌和古生态环境特征并结合生屑云岩发育规律,预测了A4井区生屑云岩储层新的空间展布范围。实际钻探结果证实了储层预测的准确性,新增探明储量近400万t,保障了BZ油田的可持续发展和投资效益。该套方案对国内海上相似地质条件油田的滚动勘探开发具有借鉴意义。 相似文献
53.
海州湾南部海域不同季节虾类数量及其分布特征 总被引:3,自引:0,他引:3
根据2009年5月、9月和12月对海州湾南部海域3个航次的渔业资源调查资料,对该海域十足目虾类的数量和分布的特征进行了初步研究,且探讨了优势种、温度、盐度、水深等因素对以上特征的影响。结果表明,5月虾类资源量最高,9月最低,12月较9月有所回升,分别以戴氏赤虾Metapenaeopsis dalei和日本鼓虾Alpheus japonicus、细巧仿对虾Parapenaeopsis tenella和刀额新对虾Metapenaeus ensis、日本鼓虾等为主要优势种。5月和9月虾类平面分布趋势均为西北外侧和东南水域较低,南面沿岸较均匀,东部和中部出现最高值;12月北面和南面近岸资源量较低,其他水域较均匀,最高值出现在东部水域。逐步回归分析表明,海州湾虾类资源量与底盐间存在显著相关关系,其他水文因素无显著相关关系。此外,优势种生态习性、赤潮和径流等是影响海州湾虾类数量和分布变化的主要因素。 相似文献
54.
One new species of free-living marine nematodes Enoplus taipingensis sp.nov.from the rocky intertidal seaweeds in the Taiping Bay,Qingdao is described and illustrated with scanning electron microscopy observation and 18S rRNA gene sequence analysis.Enoplus taipingensis is characterized by special arrangement of lateral setae on the tail,three cervical setae,distal structure on the supplement,and much longer body length with bigger De Man ratio "a".Type specimens are deposited in the College of Marine Life Science,Ocean University of China. 相似文献
55.
56.
Seasonal variability in free-living marine nematode community structure in a sandy beach of the Taiping Bay of Qingdao, China 总被引:1,自引:0,他引:1
Nematode assemblage composition, trophic structure and biodiversity were followed over an annual cycle in a sandy beach of the Taiping Bay of Qingdao, China. Nematode assemblage in the sandy beach maintained a high genus diversity (75 genera). Mlero- laimus and Bathylaimus were the dominant genus of the nematode assemblage, accounting for 66% of the total nematode abundance. The nematodes' dominant trophic structure changed seasonally as a response to the seasonal changes in food quality. Epigrowth-feeder nematodes (2A) were the dominant trophic groups in the trophic structure with the highest abundance in spring because of phytoplankton bloom, while the feeding type ( 1 B) showed higher abundance in summer that was due to the increasing of sediment detritus after spring bloom. Furthermore, species diversity and evenness calculated on nematodes identified to the genus level displayed significant temporal changes, which was also reflected by the index of trophic diversity. According to the cluster analysis, the nematode community structure of the whole year was clearly separated into two periods (A and B). Biota-Envlron- ment matching (BIOENV) results showed that seawater temperature, sediment Chl a and grain size were responsible for the nema- tode community structure variation in spring and summer period (Period A). However, seawater/interstitial water temperature, interstitial water dissolved oxygen concentration,interstitial water salinity, and sediment Ph a a were more important in constructing the autumn and winter period (Period B) nematode community structure. 相似文献
57.
夏季大亚湾悬浮颗粒有机物碳、氮同位素组成及其物源指示 总被引:4,自引:1,他引:4
2015年夏季开展了大亚湾悬浮颗粒有机物碳(POC)、氮含量(PN)及其同位素组成的研究,结果表明,δ13CPOC和δ15NPN的变化范围分别为-25.7‰~-17.4‰和-6.3‰~10.4‰,平均值分别为-20.2‰和8.2‰。大亚湾悬浮颗粒有机物含量及其碳氮同位素组成的空间变化反映了不同有机质来源的影响:喜洲岛附近海域表现出高POC、PN、δ13CPOC和δ15NPN的特征,指征着浮游植物水华的主导贡献;东北部范和港附近海域具有高POC、PN、低δ13CPOC和高δ15NPN的特征,反映了河流/河口水生有机物的影响;湾顶白寿湾附近海域的δ13CPOC和δ15NPN出现低值,体现了陆源有机质和人类污水排放的影响。借助δ13CPOC和δ15NPN的三端元混合模型,定量出海洋自生有机质、陆源有机质、河流/河口水生有机质等3个来源的贡献平均分别为70%、13%和17%,其中海洋自生有机质是夏季大亚湾悬浮颗粒有机物的最主要来源。从这3种来源颗粒有机物含量的空间变化看,海洋自生有机质含量由湾内向湾外减少,与初级生产力的空间变化相对应;河流/河口水生有机质含量在大亚湾东北部出现高值;陆源有机质含量在表、底层出现不同态势,表层陆源有机物含量在湾中部海域最低,而底层则呈现出自湾内向湾口增加的趋势,主要受控于离岸距离和珠江冲淡水、粤东沿岸上升流输送的影响。 相似文献
58.
《Marine Policy》2015
Since the first limited entry Bristol Bay drift and set gillnet permits were issued in 1975, many local residents have sold their permits to non-resident fishermen. Declining local permit ownership destabilizes the main economic base of the region. Previous studies have documented the decline of locally owned permits and have proposed social and economic hypotheses that could explain why local permit ownership is declining in limited entry fisheries in Alaska. To stem the outward flow of permits, the Bristol Bay Economic Development Corporation operates a Permit Loan Program to assist Bristol Bay watershed residents in buying permits. Despite its generous benefits, it has not reversed the decline in local permit ownership. This paper examines why residents enter or exit the fishery. Hypotheses on permit retention were tested through interviews with Bristol Bay fishery participants. Interviewees indicate stronger cultural and familial ties than economic factors to fishing. As local permit ownership has declined, these ties are being lost, leading to declining interest in the fishery. Commercial fishing is a competitive and costly enterprise. Successful participants in the fisheries, especially the drift gillnet fishery, are financially savvy with supplemental non-fishing income that outcompete residents by catching most of the fish. The Bristol Bay Economic Development Corporation Permit Loan Program appears unable to stop the local loss of permits. There are no obvious ways to expand local permit ownership and retaining local permits remains a major challenge for the region. However, it is important for local residents to participate in the fishery because it keeps communities economically and socially healthy, gives residents access to their local resources and strengthens their voice in managing their local resources. 相似文献
59.
The South African coastline has been invaded by numerous alien species. Rare pre-invasion (1980) and post-invasion datasets (2001 and 2012) exist for Marcus Island, a small land-tied island in Saldanha Bay, South Africa. These snapshot datasets of the island’s intertidal invertebrate community were complemented with monitoring across seasons, from 2014 to 2016. Invertebrate communities were compared among the summers of 1980, 2001, 2012, 2014, 2015 and 2016 to assess interannual differences, while invertebrates and algae were monitored quarter-annually to assess seasonal changes. In addition, the population dynamics of the alien mussel Mytilus galloprovincialis were monitored. Differences in invertebrate communities between consecutive summers were significant but much smaller than changes induced by the arrival of alien species. Invertebrate and seaweed communities differed among years and shore zones but not among seasons, whereas species diversity differed among years, seasons and shore zones, with zones having the strongest influence. The invasion by M. galloprovincialis, and ensuing spatial and temporal variability in its recruitment, emerged as the most important factor influencing community composition, overshadowing interannual and seasonal changes. This work highlights that the impacts of alien species can be distinguished from natural variability by combining long-term monitoring with surveys at finer temporal scales. This is an important step in extending our understanding of the impacts of marine alien species. 相似文献
60.
PM Ross RM Fairweather DP Culliford S Park CA Pilditch CN Battershill 《新西兰海洋与淡水研究杂志》2016,50(1):56-69
ABSTRACTTo investigate the uptake and depuration of polycyclic aromatic hydrocarbons associated with the Rena oil spill we sampled the surf clam Paphies subtriangulata at two open coast locations (6?km apart) just prior to oil coming ashore (7 October 2011), then at 1–3 week intervals for the next 4 months. Total polycyclic aromatic hydrocarbons (tPAH) increased at both sites from 1 to 96–124?µg?kg?1 (wet weight) by 18 October before declining to low levels (<4?µg?kg?1) by February 2012. Ongoing sampling throughout 2012–2014 included three additional sites to the north east (up to 30?km away) and a site 5?km to the south east revealing tPAH levels generally <10?µg?kg?1 except in October 2013 where levels ranged between 39–45?µg?kg?1 at all sites. A comparison of PAH component profiles with oil-contaminated beach sediment indicated that the high levels observed in surf clams between October–December 2011 were clearly associated with the Rena spill. However, the October 2013 peak had a PAH profile inconsistent with weathered Rena oil, suggesting an alternative source of contamination. Our results highlight the potential for P. subtriangulata as a PAH monitoring tool but recognise more study is needed to better quantify baseline levels and uptake and depuration dynamics. 相似文献