用营养动态模式估算东海区大陆架渔场渔业资源蕴藏量

引用在东海区渔场进行的"海洋生物资源补充调查和资源评价"获得的初级生产力调查结果,综合已有的研究数据,采用PARSONS和CUSHING营养动态模式,对东海区渔场的渔业资源蕴藏量进行了估算。结果表明:1996～2005年东海区大陆架渔场渔业资源平均营养级为3.531级,近10年渔业资源年平均蕴藏量为836×104t,可捕量为418×104t左右;其中东海陆架渔场平均资源量为591×104t,可捕量296×104t;黄海南部平均资源量为245×104t,可捕量123×104t。2002～2005年东海区大陆架渔场平均资源蕴藏量为855×104t,可捕量为428×104t左右;东海区大陆架单位面积渔业资源蕴藏量为14.59t/km2,可捕量7.5t/km2;有机碳与鱼的比例为10.32:1,在世界各渔场中均属于较高水平;东海的单位面积渔业资源蕴藏量为8.89t/km2,东海区海域单位面积渔业资源蕴藏量为10.20t/km2,可捕量分别为4.5t/km2和5.1t/km2,高于黄渤海区和南海,略低于福建海区。目前东海区大陆架渔场的年渔获量已达750×104t左右,远远超过估算的420×104t左右年可捕量水平,使渔业资源始终处于过度捕捞状态。要使渔业资源恢复到良好状态,至少要减少目前40%的渔获量。     

南海北部大陆架海洋生态系统Ecopath模型的应用与分析

过度捕捞和环境恶化导致渔业资源和海洋生态系统逆向发展。采用EwE5.1软件,对南海北部大陆架建立Ecopath(生态通道模型)模型。通过各级流量、生物量、生产量、捕捞量、系统总流量以及生态位和混和营养效应等方面的分析,得出营养流通主要有2种途径,肉食鱼类间饵料竞争非常激烈,低值鱼类间具相似的捕食压力,顶级捕食者对大部分鱼类负效应不明显。系统受过度捕捞渔业影响很大,并存在营养级I利用效率低和渔业资源小型化、低值化等不稳定的幼态特征。     

东海区海洋渔业资源近况浅析

根据2002～2004年东海区渔业资源监测调查资料、主要捕捞鱼种的生物学资料和中国渔业统计年鉴,对东海区近3 a季节间的资源密度、渔业生物学性状以及历年来的渔获群落结构组成、单位捕捞力量渔获量动态比较,分析东海区海洋渔业资源近况.结果表明:虽然近几年东海区海洋渔业捕捞产量维持在历史高水平,但主要是依赖于超高的捕捞力量、实施伏季休渔制度使群体资源得到暂时的养护等措施.主要经济鱼种的亲鱼量年间变化不大且处于相对缺乏的状态,渔获物小型化、利用资源主体以当龄鱼为主、单位捕捞力量渔获量下降等过度捕捞现象十分明显,资源基础相当脆弱,渔业资源衰退之势仍在加剧.秋季调查资源密度的年间波动取决于补充量水平,其水平的高低与环境因子密切相关.     

夏季东海陆架浮游植物类群结构对不同风场条件的响应分析

为探讨东海的主要物理过程对浮游植物生物量和类群结构的时空分布影响,采用高效液相色谱法分析2006年和2011年夏季东海陆架条件下的浮游植物光合色素的组成及含量,并通过CHEMTAX对浮游植物群落的结构进行分析。结果表明,不同风场条件下东海浮游植物生物量和类群结构均有显著差异。在2006年夏季航次,受弱西北风的控制,长江冲淡水向外延伸面积较大,东海陆架叶绿素a的平均浓度为1 228.6ng/L,主要特征光合色素多甲藻素(Peri)、19-己酰基氧化岩藻黄素(19-hex)、19-丁酰基氧化岩藻黄素(19-but)、玉米黄素(Zea)和二乙烯基叶绿素a(DV-Chl.a)相对较高,浮游植物以硅藻(41%)和甲藻(16%)为主要优势类群;2011年夏季航次,受强东南风影响,底层低温高盐水涌升现象明显,东海陆架叶绿素a(Chl.a)的平均浓度(2 677.9ng/L)比2006年高一倍,叶绿素b(Chlb.)、青绿藻素(Prasino)、新黄素(Neo)和别藻黄素(Allo)等光合色素浓度相对较高,硅藻(60%)在浮游植物群落中占主要优势。     

跨世纪东海渔业资源利用和管理若干问题的探讨

应用近几年调查研究和监测资料,对世纪之交东海渔业资源的利用现状和存在问题作出了分析和评价,并较系统地分析、阐述了渔业资源开发利用潜力和应采取的相应对策。针对目前东海渔业管理上出现的新情况、新问题,从合理、科学和持续利用东海渔业资源的角度考虑,提出了延长伏季休渔时间、实施拖虾休渔期、规范电脉冲捕捞和管理、完善张网休渔管理、加强梭子蟹资源保护、严格渔具标准、限制作业调整范围等渔业管理方法、措施和建议方案。     

西北太平洋环流和海温数值模拟

基于Ecom-si建立了一个西北太平洋海洋数值模式,综合考虑了侧边界通量、海表面风应力、热通量、蒸发和降水等因素,模拟并分析了西北太平洋环流和海温的基本特征.模式验证结果表明,模式计算的海温与日本2008年西北太平洋实测温度走航断面资料吻合良好.模式再现了低纬度海区表层自东向西流动的北赤道流、强西边界流黑潮、东海的台湾...     

浙江蟹笼渔业现状的探讨

蟹笼渔业是在20世纪90年代以后迅速发展起来的新兴捕捞作业,目前已成为我国东海区和浙江省海洋捕捞的重要作业方式之一。着重介绍了浙江蟹笼渔业渔具的规格及特点,近年来浙江蟹笼渔业的发展概况,蟹笼作业主要生产渔场、渔期及渔获物组成。分析研究了蟹笼渔船的经济效益和劳动力构成,并对当前浙江蟹笼渔业存在的问题,提出了相应的解决方法和管理建议。     

南海北部大陆架海洋生态系统Ecosim模型的动态模拟

为了确定最佳的渔业政策,采用EwE 5.1软件,对南海北部大陆架海洋生态系统构建了1987-1998年Ecosim(时间动态)模型。Ecosim模型包含了32个功能组,初始参数来源于20世纪80年代末期静态平衡的Ecopath模型。通过营养关系,分析了渔业捕捞对主要经济鱼类的动态影响。结果显示1998年系统总输出、总生物量都有不同程度的增加,而总捕捞量则有所降低;强化的捕捞压力导致了低值小型鱼类被捕食压力的间接缓解,大中型高价值鱼类的生物量发生明显下降;说明了生态系统呈现出逆向发育的主要原因在于过度捕捞所产生的从上而下(top-down)的控制作用。     

Functional diversity governs ecosystem response to nutrient enrichment

The relationship between species diversity and ecosystem functioning is a central topic in ecology today. Classical approaches to studying ecosystem responses to nutrient enrichment have considered linear food chains. To what extent ecosystem structure, that is, the network of species interactions, affects such responses is currently unknown. This severely limits our ability to predict which species or functional groups will benefit or suffer from nutrient enrichment and to understand the underlying mechanisms. Here our approach takes ecosystem complexity into account by considering functional diversity at each trophic level. We conducted a mesocosm experiment to test the effects of nutrient enrichment in a lake ecosystem. We developed a model of intermediate complexity, which separates trophic levels into functional groups according to size and diet. This model successfully predicted the experimental results, whereas linear food-chain models did not. Our model shows the importance of functional diversity and indirect interactions in the response of ecosystems to perturbations, and indicates that new approaches are needed for the management of freshwater ecosystems subject to eutrophication.     

Ecological studies on Prochlorococcus in China seas

Prochlorococcus, a tiny oxygenic photosynthetic picoplankton with unique pigment composition, has been found to be ubiquitous and abundant in the world oceans, and has been recognized to be closely related to living resources and environmental issues. It has attracted the interest of marine biologists since its discovery, and field data on it over global oceans have accumulated rapidly in the past 10 years. In China, we have studied Prochlorococcus for 8 years, achieving a basic ecological understanding. The presence of Prochlorococcus in China seas, marginal seas of the west Pacific, was confirmed, and its distribution patterns were also brought to light. Prochlorococcus is very abundant in the South China Sea and the offshore regions of the East China Sea. It is seasonally present in the southeast part of the Yellow Sea and absent in the Bohai Sea. Temporal and spatial variations of the abundance of Prochlorococcus and their affecting factors, physiological and ecological characteristics of Prochlorococcus and their relationships to the other groups of picoplankton, and the importance of Prochlorococcus in total biomass and possible roles in living resources and environmental problems are discussed. In the future, isolation of different Prochlorococcus strains from the China seas and their physiological characteristics, genetic diversity, phylogenies and gene exploiture, etc. are important issues to be addressed.     

东海北部、黄海南部刺鲳的资源状况

根据对5艘深水流网资源信息船1998年8月～2001年3月连续渔捞调查资料进行分析研究,结果表明:刺鲳是本海域深水流网渔业的三大优势种之一(方头鱼占首位,刺鲳和白姑鱼年间变动量相互交替),占年总渔获量的8.68%～27.16%;周年数量分布集中在夏、秋季,全年数量最高值出现在夏末初秋.渔获物重量分布以舟外渔场最多,为49.71%,其次是鱼山、鱼外、沙外、江外等渔场.     

Preservation of black carbon in the shelf sediments of the East China Sea

Concentrations and carbon isotopic(14C,13C) compositions of black carbon(BC) were measured for three sediment cores collected from the Changjiang River estuary and the shelf of the East China Sea. BC concentrations ranged from 0.02 to 0.14 mg/g(dry weight) ,and accounted for 5% to 26% of the sedimentary total organic carbon(TOC) pool. Among the three sediment cores collected at each site,sediment from the Changjiang River estuary had relatively high BC contents compared with the sedi-ments from the East China Sea shelf,suggesting that the Changjiang River discharge played an im-portant role in the delivery of BC to the coastal region. Radiocarbon measurements indicate that the ages of BC are in the range of 6910 to 12250 years old B.P.(before present) ,that is in general,3700 to 9000 years older than the 14C ages of TOC in the sediments. These variable radiocarbon ages suggest that the BC preserved in the sediments was derived from the products of both biomass fire and fossil fuel combustion,as well as from ancient rock weathering. Based on an isotopic mass balance model,we calculated that fossil fuel combustion contributed most(60%―80%) of the BC preserved in these sediments and varied with depth and locations. The deposition and burial of this "slow-cycling" BC in the sediments of the East China Sea shelf represent a significant pool of carbon sink and could greatly influence carbon cycling in the region.     

The trophic fingerprint of marine fisheries

Biodiversity indicators provide a vital window on the state of the planet, guiding policy development and management. The most widely adopted marine indicator is mean trophic level (MTL) from catches, intended to detect shifts from high-trophic-level predators to low-trophic-level invertebrates and plankton-feeders. This indicator underpins reported trends in human impacts, declining when predators collapse ("fishing down marine food webs") and when low-trophic-level fisheries expand ("fishing through marine food webs"). The assumption is that catch MTL measures changes in ecosystem MTL and biodiversity. Here we combine model predictions with global assessments of MTL from catches, trawl surveys and fisheries stock assessments and find that catch MTL does not reliably predict changes in marine ecosystems. Instead, catch MTL trends often diverge from ecosystem MTL trends obtained from surveys and assessments. In contrast to previous findings of rapid declines in catch MTL, we observe recent increases in catch, survey and assessment MTL. However, catches from most trophic levels are rising, which can intensify fishery collapses even when MTL trends are stable or increasing. To detect fishing impacts on marine biodiversity, we recommend greater efforts to measure true abundance trends for marine species, especially those most vulnerable to fishing.     

Impact of climate change on marine pelagic phenology and trophic mismatch

Phenology, the study of annually recurring life cycle events such as the timing of migrations and flowering, can provide particularly sensitive indicators of climate change. Changes in phenology may be important to ecosystem function because the level of response to climate change may vary across functional groups and multiple trophic levels. The decoupling of phenological relationships will have important ramifications for trophic interactions, altering food-web structures and leading to eventual ecosystem-level changes. Temperate marine environments may be particularly vulnerable to these changes because the recruitment success of higher trophic levels is highly dependent on synchronization with pulsed planktonic production. Using long-term data of 66 plankton taxa during the period from 1958 to 2002, we investigated whether climate warming signals are emergent across all trophic levels and functional groups within an ecological community. Here we show that not only is the marine pelagic community responding to climate changes, but also that the level of response differs throughout the community and the seasonal cycle, leading to a mismatch between trophic levels and functional groups.     

东海黄海渤海8个主要分潮的数值模拟

应用球面坐标系下ECOM数值模式,数值模拟了东海黄海渤海的8个主要分潮M₂、S₂、N₂、K₂、K₁、O₁、P₁和Q₁.采用高分辨率网格,计算区域包括东海黄海渤海、东海陆架坡和琉球以东西北太平洋,考虑实际水深和岸线.开边界条件由全球大洋潮汐模式计算的调和常数给出.较成功地模拟出了8个分潮的传播特征,再现了计算区域内半日分潮的5个无潮点和2个蜕化的半个无潮点、全日分潮的3个无潮点.与65个潮位站的观测资料比较,模式计算的M₂、S₂、K1和O₁分潮振幅和位相的均方差分别为7.85 cm和6.81°,5.04cm和8.14°,3.82cm和13.04°,4.34cm和9.33°.与17个潮位站的观测资料比较,N₂、K₂、P₁和Q₁分潮振幅和位相的均方差分别为3.64cm和7.89°,8.47cm和10.51°,1.76cm和7.56°,1.50cm和26.34°.模式模拟的结果可为河口海岸小区域模式提供较为可靠的外海开边界潮汐调和常数资料.     

Potential relationships between atmospheric particulate matter transported by winter monsoons and red tides in the East China Sea

Combining numerical diagnosis from atmospheric science with biogeochemical methods,a model of the potential correlation of monsoons with red tide emergence in the East China Sea is constructed.The model is designed based on an in-depth investigation of the time-space relationship of aerosol and red tide events in the East China Sea from 2005 to 2006,and a continuous monitoring of atmospheric particulates at two stations.The study shows that every red tide event investigated has a close relationship with aerosols coming from the northwest (wind direction in winter) along with subsidence flow.The elemental abundance of total suspended particulate in Hangzhou and Tiantai is different from that of soil background levels,indicating atmospheric particulates there are brought in by winter winds.There is a significant correlation between the content of iron and phosphorous in atmospheric particulates,which mainly exist in binding materials between particulates.In addition,the confined absorption of iron and phosphorous by red tides is related to the intensity of sunlight.These results provide new information regarding the mechanism for the high frequency of red tides in the East China Sea.The results also provide a scientific basis for establishing new pathways for pre-warning and forecasting of red tide disasters.     

生态系统的可靠性及其稳定性的维持

 生态系统的营养结构是由营养级组成的.可靠性模型实验表明,营养级的可靠性取决于物种的失效率大小,物种丢失对物种丰富、失效率高的营养级的可靠性影响甚微,而对物种贫乏、失效率低的营养级略大,换言之,营养级的可靠性与物种的丰富度无紧密关系.其次,在营养级可靠性相同的条件下,简单系统的可靠性普遍略高于营养级多或食物链长的复杂生态系统.生物多样性与生态系统的稳定性没有必然联系,只要营养级还存在(无论剩下几个物种),那么按串并联方式组合成的生态系统就不会崩溃.生态系统的稳定性是冗余结构的稳定性.生态系统经常遭受干扰,但物种和个体的丢失可以通过来自其内外源源不断的冗余补充,以维持生态系统营养结构的稳定性.     

基于ArcView GIS的东海虾蟹类生物资源量评估模式及成图方法

根据“东海虾蟹类生物资源量评估模式及成图方法的建立“的成图和建模工作的实践经验，介绍了利用计算机GIS技术制作生物资源量时空分布图的方法，并就该项技术在生物资源量评估模式的发展方向展开了讨论。     

关于东海区灯光围网管理的研究

对1998～2005年东海区灯光围网的主捕品种、数量分布及其捕捞规模进行调研,研究认为灯光围网的主捕品种为日本鲐、澳洲鲐、竹筴鱼和蓝圆鲹等,且尚有一定的资源量。东海区的灯光围网近年来规模发展迅速,对上述鲐鲹鱼有良好的诱捕效果。从可持续利用资源角度出发,对其应实施规范管理,其措施为:(1)确定大型机轮围网、机帆船灯光围网的规模数量、渔船吨位、马力、网具规格等;(2)实行捕捞许可证制度;(3)成立全国灯光围网协会,配合农业部渔业局对灯光围网制订有关措施,进行专项管理。     

热带岛礁型海洋牧场中珊瑚礁生境与资源的修复

我国南海的离岸岛礁以珊瑚礁生境为主。珊瑚礁在提升海洋生态资源和维护我国海洋国土权益上发挥了至关重要的作用。近年来,在全球气候变化以及人类活动的影响下,南海珊瑚礁生境和资源严重退化,威胁着渔业资源、海洋环境以及国土安全。现代化的海洋牧场被认为是实现南海资源可持续发展战略的新型海洋生物资源开发模式。珊瑚礁生境与资源的修复则是热带岛礁型海洋牧场建设的基础和关键。基于此,本文整理了珊瑚礁生境与资源修复的技术方法,详细介绍了珊瑚礁生境构建框架生物造礁石珊瑚的有性繁殖、断枝培育、底播移植等技术方法以及珊瑚礁其他特色生物资源人工放流技术,并提出了在珊瑚礁生境与资源修复中所面临的问题及相应对策。