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近1000年来西格陵兰荷尔斯泰因斯堡港生物硅指示的海洋生产力变化 总被引：1，自引：1，他引：0
We analyzed the biogenic silica(BSi) content and produced a diatom-based summer sea-surface temperature(SST) reconstruction for sediment core GC4 from the Holsteinsborg Dyb, West Greenland. Our aim was to reconstruct marine productivity and climatic fluctuations during the last millennium. Increased BSi content and diatom abundance suggest relatively high marine productively during the interval of AD 1000–1400, corresponding in time to the Medieval Warm Period(MWP). The summer SST reconstruction indicates relatively warm conditions during AD 900–1100, followed by cooling after AD 1100. An extended cooling period during AD 1400–1900 is characterized by prolonged low in reconstructed SST and high sea-ice concentration. The BSi values fluctuated during this period, suggesting varying marine productivity during the Little Ice Age(LIA).There is no significant correlation between the BSi content and SST during the last millennium, suggesting that the summer SST has little influence on marine productively in the Holsteinsborg Dyb. A good correspondence between the BSi content and the element Ti counts in core GC4 suggests that silicate-rich meltwater from the Greenland ice sheet was likely responsible for changes in marine productively in the Holsteinsborg Dyb. 相似文献
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Ultraviolet(UV) radiation has a significant influence on marine biological processes and primary productivity;however, the existing ocean color satellite sensors seldom contain UV bands. A look-up table of wavelengthintegrated UV irradiance(280–400 nm) on the sea surface is established using the coupled ocean atmosphere radiative transfer(COART) model. On the basis of the look-up table, the distributions of the UV irradiance at middle and low latitudes are inversed by using the satellite-derived atmospheric products from the Aqua satellite,including aerosol optical thickness at 550 nm, ozone content, liquid water path, and the total precipitable water.The validation results show that the mean relative difference of the 10 d rolling averaged UV irradiance between the satellite retrieval and field observations is 8.20% at the time of satellite passing and 13.95% for the daily dose of UV. The monthly-averaged UV irradiance and daily dose of UV retrieved by satellite data show a good correlation with the in situ data, with mean relative differences of 6.87% and 8.43%, respectively. The sensitivity analysis of satellite inputs is conducted. The liquid water path representing the condition of cloud has the highest effect on the retrieval of the UV irradiance, while ozone and aerosol have relatively lesser effect. The influence of the total precipitable water is not significant. On the basis of the satellite-derived UV irradiance on the sea surface, a preliminary simple estimation of ultraviolet radiation's effects on the global marine primary productivity is presented, and the results reveal that ultraviolet radiation has a non-negligible effect on the estimation of the marine primary productivity. 相似文献
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To characterize environmental factors controlling decadal-scale variations in the buried flux of marine organic carbon(BF_(C_m)) in the eastern shelf sea areas of China(ECSS),four well preserved sediment cores collected from the central Yellow Sea mud(CYSM) area,the Yellow Sea Coastal Current(YSCC) area and the Changjiang River Estuary(CRE) were investigated in this study.In the CYSM,variations in BF_(C_m) were found to be dependent on variations in primary productivity and to exhibit a cyclical trend possibly related to fluctuations in the Pacific Decadal Oscillation(PDO) and the East Asian winter monsoon index(EAWM).In the YSCC,BF_(C_m) likewise depends on primary productivity.Prior to the 1950s,variations in BF_(C_m) were similar to that of the EAWM.After the 1950s,BF_(C_m) increased rapidly and exhibited maximum values in the surface layer,consistent with an increase in primary productivity caused by the input of terrestrial nutrients associated with China's economic development.In the CRE,variations in BF_(C_m) were affected by several competing factors making it difficult to identify clear relationships between variations in BF_(C_m) and primary productivity.In contrast,long-term variability in BF_(C_m) is more similar to changes in the Changjiang River sediment load.Thus,it is speculated that the construction of dams along the Changjiang River may be the main cause of variations in BF_(C_m) in this area.Given the disproportionate effects of human activities on marine environments and decadal variations in BF_(C_m) in the ECSS,careful attention should be paid to regional differences in organic carbon preservation and environmental changes lest estimates of these values be made imprecise or inaccurate. 相似文献
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海洋浮游植物光合作用固碳在全球碳循环中扮演着极为重要的角色, 获取不同光衰减对应的海水深度, 对于采集水样用于海洋初级生产力的研究具有重要意义。本研究于国际上首次开发了无缆便携式海洋透光率仪, 特殊的光学结构设计和光谱滤光技术使得光谱响应在波段400~700nm范围内超过了同类海洋传感器, 特定光衰减下对应的深度误差小于0.5m。将本设备应用于南海中尺度涡旋初级生产力的研究中, 在采样率和自动化方面验证了仪器的便携性; 通过对涡旋中初级生产力的空间分布规律进行分析, 检验了仪器数据结果的可靠性。海洋透光率仪在价格、准确性、可靠度和操作的便携性上具有不可比拟的优势, 将在未来海洋生态环境的研究中发挥重要作用。 相似文献
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生物活性铁(Fe)进入生物地球化学循环中能够调节碳循环,影响海洋初级生产力,间接影响全球气候变化。决定Fe生物可利用度的关键因子是可溶Fe含量,其中大气气溶胶的长距离传输是上层海洋获取生物可利用Fe的重要来源。近年来,对气溶胶中的Fe及溶解度的研究取得了重要进展,包括对不同区域Fe质量浓度和溶解度的观测以及对Fe溶解度影响因素的讨论。基于以上研究成果,汇总了近二十年全球部分陆地和海洋站点观测所得的不同粒径气溶胶颗粒物中的Fe质量浓度及其溶解度数据;重点介绍了气溶胶沉降入海洋前影响Fe溶解度的主要因素,包括Fe的来源、大气物理过程以及大气化学和传输混合过程等,并就各影响因素间的关联及相对重要性展开讨论;对未来气溶胶Fe的研究方向和方法提出建议。 相似文献
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南海北部4万年以来有机碳和碳酸盐含量变化及古海洋学意义 总被引：2，自引：0，他引：2
南海北部陆坡的17937柱状样上部4万年来有机碳和碳酸盐的含量分布特征显示：有机碳含量总体显示出冰期高、间冰期低的特征，碳酸盐则相反。C／N元素比分布范围和二组分分析说明该站位的有机碳以海洋自生有机碳为主，全新世达80％以上。根据海洋沉积物中总有机碳含量和两类不同来源有机碳所占比例计算得出的海洋自生生物产生的有机碳含量在MIS2时期最高，说明末次冰期海洋生产力提高。冰期冬季风强化，海水混合程度加强，营养物质利用更充分以及陆源输入增多导致营养物质增加。碳酸盐含量主要受陆源物质稀释的影响，为“大西洋型”旋回。碳酸盐旋回在全新世早中期存在低碳酸钙事件，可能与该时期的强降雨冲刷所致陆源稀释作用增强、海水溶解作用增强以及海洋表层生产力的降低等综合作用相关。 相似文献
8.
近年来关于海洋经济增长效率的研究层出不穷,但是目前尚未有文献对其进行过系统的综述。本文从技术进步中性与海洋经济传统全要素生产率、技术进步中性与海洋经济绿色全要素生产率、技术进步偏向与传统全要素生产率、技术进步偏向与绿色全要素生产率四方面对海洋经济增长理论进行了文献梳理,分析总结了近年来学者们在海洋经济增长效率领域的主要研究发现。通过梳理发现:当前研究存在的技术进步中性假设使得现有成果无法解释海洋科技进步在海洋经济增长与海洋资源环境之间的作用机制;偏向性技术进步方法研究以基于CES生产函数的参数分析法为主;缺少偏向性技术进步与海洋经济绿色增长效率两者综合效应的系统分析。最后针对各问题给出了下一步研究方向。 相似文献
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《African Journal of Marine Science》2013,35(3):449-464
The SEAChange programme, instituted in 2007 under the auspices of the South African Network for Coastal and Oceanic Research (SANCOR), included four interdependent research themes, one of which was Marine Biotechnology. Marine biotechnology is a discipline that involves both basic and applied research, and is aimed at the commercial exploitation of marine organisms. This paper reviews the progress made in three key areas of the SEAChange programme over the first five years, namely marine aquaculture, omics of marine organisms and marine bioprospecting, and discusses these accomplishments in context to marine biotechnology internationally. 相似文献
11.
国外海洋抗肿瘤活性物质的研究与开发 总被引：15，自引：0，他引：15
海洋生物是抗肿瘤活性物质的重要来源。近十几年来，已从不同的海洋生物中分离鉴定了许多结构新颖的抗肿瘤活性物质，显示出诱人的研究开发前景。本文综述了目前国外从海洋动物、海洋植物和海洋微生物抗肿瘤活性物质的研究开发进展。 相似文献
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资源环境承载力研究亟待突破承载阈值界定与关键参数率定的技术瓶颈，并建立一套标准化的定量评价关键技术。本研究基于“资源量?消费量”模型，通过调查与实验分析获取特定海区的初级生产力、浮游植物有机碳含量、鱼类营养级等关键参数值，采用营养动态模型和Tait沿岸海域能流模型来估算海洋生物资源总量，然后根据年人均水产品摄入量或年人均蛋白质摄入量来计算该海区海洋生物资源承载力的阈值。根据2016年对日照辖区海域的生态环境状况调查，该海域年平均初级生产力(以C计)为428.22 mg/(m2·d)，浮游植物年生产量为918.51万t，鱼类、虾蟹类和头足类的平均营养级分别为3.85、3.92和3.90，利用营养动态模型计算海域渔业资源(鱼类、虾蟹类和头足类)的年生产量为3.89万t；根据Tait沿岸海域能流模型计算日照10 m等深线以内浅海的除去壳重的贝类资源量为5.50万t。按照年人均水产品摄入量为21 kg，计算出日照辖区海域的海洋生物资源承载力总和为192.86万人；按照年人均摄入蛋白质量为30 kg，计算出日照辖区海域的海洋生物资源承载力总和为16.87万人。本文建立了一项具有广泛适用性的海洋生物资源承载力定量评价技术，对科学地开发利用海洋生物资源和建立陆海统筹的资源环境承载力的监测预警机制起到积极的促进作用。 相似文献
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运用可持续发展理论 ,在改进了国内著名学者潘家华所提出的模型基础上 ,构造了海洋经济可持续发展理论模型。新模型的构造与应用得到了一些有意义的结果 ,为制定海洋开发利用政策提供了更充分的理论依据。 相似文献
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本研究采用色谱质谱(GC-MS)和色谱-同位素质谱(GC-IRMS)方法,对珠江口盆地Site4B沉积物中脂肪醇分子化合物分布以及单体碳同位素组成进行了研究。结果表明:长链脂肪醇碳优势指数(CPIC26—34:9.41—24.56)、平均碳链长度(ACLC26—34:28.85—29.99)以及n C26—n C30脂肪醇平均碳同位素组成(?29.13‰±0.87‰、?32.98‰±1.28‰和?32.73‰±1.61‰)均揭示了n C26—n C34脂肪醇属于陆源高等植物来源,n C16—n C20和n C24脂肪醇较正的碳同位素组成反映了化合物的海洋细菌来源,而n C22脂肪醇偏负的碳同位素特征(平均?33.26‰±1.51‰)反映了化学自养细菌来源。Site4B沉积物中的陆源输入主要来自南海周边河流,从12.7ka BP至今的沉积时期(0—80cm,文中深度均为埋深)和末次冰盛期(102—120cm),其陆源输入主要来自台湾岛河流,而在19.3—12.7ka BP沉积时期(80—102cm)和更新世沉积时期(120—300cm),台湾岛、吕宋岛和珠江口河流的陆源贡献普遍较低。Site4B沉积物中的海洋生产力主要来自海洋微生物输入的贡献,并主要受到海水温差影响;其中在35—150cm层位,海洋输入和南海暖流的强弱带来的海水温度的高低有关,而在150—300cm层位,则主要和冰期-间冰期的冷暖气候带来的海水温差有关。 相似文献
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M.A. Burford D.M. Alongi A.D. McKinnon L.A. Trott 《Estuarine, Coastal and Shelf Science》2008,79(3):440-448
Tropical estuaries are under increasing pressure worldwide from human impacts, but are poorly studied compared with temperate systems. This study examined a tropical macrotidal estuary, Darwin Harbour, in northern Australia, using a combination of direct measurements and literature values to determine the main sources of primary production and the sources of nutrients supporting growth. The main source of primary production was calculated to be the extensive area of fringing mangroves and resulted in a net autotrophic system (PG:R = 2.1). Much of the carbon in the mangrove forests appears to be retained within the forests or respired, as the water column was also net autotrophic despite the carbon inputs. Phytoplankton were the second largest primary producer on a whole-of-harbour basis, with low biomass constrained by light and nutrient availability. The phytoplankton were likely to be nitrogen (N) limited, based on low N:phosphorus (P) ratios, low dissolved bioavailable N concentrations (ammonium (NH4+), nitrate (NO3−), urea), and evidence that phytoplankton growth in bioassays was stimulated by NH4+ addition. The largest new source of N to the system was from the ocean due to higher N concentrations in the incoming tides than the outgoing tides. Atmospheric inputs via N fixation on the intertidal mudflats and subtidal sediments were substantially lower. The rivers feeding into the harbour and sewage were minor N inputs. Nitrogen demand by primary producers was high relative to available N inputs, suggesting that N recycling within the water column and mangrove forests must be important processes. Darwin Harbour is adjacent to the rapidly growing urban area of Darwin city, but overall there is no evidence of anthropogenic nutrient inputs having substantial effects on primary production in Darwin Harbour. 相似文献
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21世纪是海洋世纪,人类对海洋资源开发利用的重视程度达到前所未有的高度.如何在有效开发利用海洋资源和发展海洋经济时更好地保护海洋资源环境已成为沿海国家与地区的重要战略.因此,海洋生态经济研究已引起学术界和政府部门的普遍重视.构建海洋生态经济学学科体系,对海洋经济的稳定增长和持续发展具有十分重要的意义.在分析海洋生态经济学学科体系构建基点的基础上,从海洋生态经济学研究对象与研究内容、学科属性与学科关联、学科体系构架与主要分支学科等方面探讨了海洋生态经济学学科体系构建问题,指出海洋生态经济学研究中学科体系研究的范围和侧重方向,从理论与应用方面划分海洋生态经济学的二、三级分支学科体系,并进一步探讨了其发展趋势. 相似文献
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随着海洋事业的不断深入发展,根据海洋环境的易变性、复杂性、海洋观测预报工作的地位和作用,越来越显著,本文结合我国实际情况和技术装备水平,论述了海洋观测预报系统向着现代化、自动化方向发展的重要性和必要性,同时为适应我国国情需要和与国际ＧＯＯＳ工作接轨的需要,提出了四点合理化建议供借鉴参考 相似文献
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论我国的海洋产业结构及其优化 总被引：19，自引：0，他引：19
海洋产业结构是指各海洋产业部门之间的比例构成以及它们之间相互依存、相互制约的关系。海洋产业结构是否合理，对一个国家的海洋经济发展至关重要。分析了海洋产业的划分方法以及我国海洋产业结构的现状及存在的问题，论述了我国海洋产业结构优化的目标、原则和具体措施，为海洋经济协调、稳定、快速发展提供参考依据。 相似文献
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海洋监测高技术的需求与发展 总被引：7，自引：1，他引：6
海洋监测高技术现已成为世界各海洋国家研究发展的重点,在建立海洋环境自动监测系统方面做了大量的工作,取得了许多成功的经验。本文了社会发展和经济建设对海洋监测高技术的需求,介绍了国内外在海洋监测技术方面所取得的进展,提出了我国发展海洋监测高技术的框架建议。 相似文献
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我国海洋测流仪器的发展与现状 总被引：3，自引：0，他引：3
本文介绍了建国以来海洋测流仪器发展的几个主要阶段,以翔实的背景资料,论述了我国海洋测流仪器的发展与现状,肯定了我国的海洋测流仪器发展中所取得的成绩,找出了差距,并提出了今后我国海洋测流仪器的发展方向 相似文献