【作者】 林群；

【导师】 金显仕；

【作者基本信息】 中国海洋大学 ， 渔业资源， 2012， 博士

【摘要】 本论文以海洋食物网作为海洋生态系统整合研究的重要切入口,以Ecopath with Ecosim模型为主要研究方法,构建和比较黄渤海典型水域,包括黄渤海、长江口邻近海域以及莱州湾的生态系统模型,分析典型海域生态系统的结构与功能、能量流动与营养相互关系,评价捕捞对生态系统的影响,探讨莱州湾中国对虾增殖放流的生态容量等,为基于生态系统水平的渔业管理提供基础研究依据。主要研究结果如下：(1)根据2000-2001年间的渔业资源、生态环境的调查数据,构建了包括22个功能群的黄海南部海域生态系统的Ecopath模型。结果表明,2000-2001年间主要高营养级生物(鱼类、虾蟹、头足类等)的营养级范围是2.78-4.39,渔获物的平均营养级是3.24。生态系统的营养流动主要是发生在食物网的较低营养级部分,系统营养转换效率是8.1%,其中,7.1%来自碎屑,9.3%来自初级生产者浮游植物。从第Ⅱ营养级到更高营养级间的转换效率分别是：5.0%,5.7%,18.5%和19.7%-20.4%。初级生产者食物链对生态系统能量总流动的贡献是61%,碎屑食物链是39%。渔业捕捞活动对大多数捕捞种类有负影响作用,黄海南部的捕捞压力较大,系统的渔业总效率值较高,维持渔业活动所需要的初级生产量也较高,均高于全球趋势。通过估计系统的各种生态参数,当前黄海南部生态系统处于不成熟的、不稳定的阶段。(2)根据2000年秋季和2006年秋季长江口及邻近海域渔业资源和生态环境调查数据,构建两个时期的Ecopath模型,比较分析了三峡工程蓄水前后该海域生态系统的结构、能量流动的特征,探讨三峡工程对河口生态系统的影响。三峡蓄水后低营养级层次渔获物数量增加,引起渔获物的平均营养级下降,从3.37降至3.33。相同食性的鱼类功能群的捕捞、捕食死亡率比例也发生一定的变化,捕捞死亡率仍占较高比例,生态营养效率值两个时期都具有较高值。2006年秋季总生物量、系统总流量、总初级生产量与净生产量比2000年秋季有增加趋势,第Ⅰ营养级的总流量较2000年秋季增加了23%；初级生产者食物链的转换效率增加,碎屑链的重要性略有降低。2006年秋季聚合度值较2000年秋季稍高,FML、FCI等系统成熟度指数比较接近,相差不大,两个时期长江口及邻近海域生态系统均处于脆弱的不稳定期。(3)根据1982年和1992年渤海渔业资源和生态环境的历史数据,构建2个时期的Ecopath模型,比较分析了10年间渤海生态系统结构以及渔业资源的变化。模型包含鳀、黄鲫、蓝点马鲛、其它中上层鱼类、小黄鱼、花鲈、其它底层鱼类、底栖鱼类、浮游动物、浮游植物、碎屑等17个功能群。研究发现,1992年渤海生态系统的总生物量比1982年有所下降：小型中上层鱼类成为渔业资源的主要成分,其生物量较1982年明显增加；渔获物平均营养级有所下降。从系统规模看1982年大于1992年,1982年到1992年的十年间,引起渤海生态系统结构变化的主要原因是初级生产力的变化以及捕捞因素。1982年与1992年渤海生态系统均处于脆弱的不稳定期,仍有较高的剩余生产量有待利用,因此渔业资源的恢复和增加具有一定的物质基础。(4)以1982年的渤海Ecopath静态模型为起始状态,设置相同的各功能群,利用CPUE和渔业相对捕捞强度作为时间强制序列,构建渤海Ecosim模型,模拟1982-2008年渤海生态系统发育的动态变化及其捕捞的影响。研究发现,1982-2008年间,只有口虾蛄的生物量保持上升趋势,主要经济鱼种小黄鱼、蓝点马鲛、鲲、花鲈、黄鲫等的生物量均呈下降趋势,虾蟹类、头足类的生物量相对稳定。渔获物平均营养级在1982-2008年间明显下降,总捕捞产量在1984年之后一直保持上升趋势,两者之间存在显著的负相关；FIB指数的变动与捕捞产量的变动保持一致。Q-90多样性指数在1982-1987年间处于波动状态,从1988-1994年间保持增长趋势,在1994年之后迅速下降,由2.5降至0.5附近,生态系统的生物多样性下降。模型终止状态(2008年)与起始状态(1982年)的比较表明,成熟度降低,生态系统出现一定程度退化,渔业捕捞是渔业生态系统出现退化的主要原因,降低了生态系统总体的生物量水平。(5)根据2009-2010年的莱州湾渔业资源与生态环境数据,构建了由26个功能群组成的莱州湾生态系统Ecopath模型,分析了生态系统的总体特征、营养相互关系与关键种,计算了放流品种中国对虾的增殖生态容量。系统的总体特征参数：系统的总初级生产量/总呼吸(TPP/TR)为1.53、总初级生产量/总生物量(TPP/B)为24.54,同时具有较低的循环指数(FCI=0.07)、较高的剩余生产量434.41t·km-2yr-1和较低的系统连接指数(CI=0.29),综合表明该系统目前处于脆弱的不稳定期。关键种分析得出中国对虾目前不是莱州湾生态系统的关键种,当前中国对虾的生物量是0.1143t·km-2,有较大的增殖潜力；当生物量增长到25.8倍时将不会超过增殖生态容量2.9489t·km-2。更多还原

【Abstract】 Based on Ecopath with Ecosim software, food web as an important cut-in point of integrated marine ecosystem research, the typical waters of the Yellow and Bohai Sea ecosystem model were constructed, including the Yellow and the Bohai Sea, the Yangtze River Estuary and adjacent waters and Laizhou Bay. The trophic interactions, energy flow, ecosystem structure and function and fishing impact on the ecosystems were analyzed, and ecological carrying capacity of stock enhancement of Chinese shrimp was discussed in Laizhou Bay. The aims of present thesis are to provide basic information for ecosystem-based fisheries management. The main results were as follows:(1) A trophic mass-balance model of the southern Yellow Sea during2000-2001was constructed, including22important functional groups and their diet composition studied. The trophic levels of fish, shrimp, crabs, and cephalopods were between2.78and4.39, and the mean trophic level of the fisheries was3.24. The trophic flows within the food web occurred primarily in the lower trophic levels. The mean trophic transfer efficiency was8.1%, of which7.1%was from primary producers and9.3%was from detritus within the ecosystem. The transfer efficiency between trophic levels Ⅱ to Ⅲ to IV to V to> V was5.0%,5.7%,18.5%, and19.7%-20.4%, respectively. Of the total flow, phytoplankton contributed61%and detritus contributed39%. Fishing was defined as a top predator within the ecosystem, and had a negative impact on most commercial species. Moreover, the ecosystem had a high gross efficiency of the fishery and a high value of primary production required to sustain the fishery. Together, the data suggest there is high fishing pressure in the southern Yellow Sea. Based on analysis of Odum’s ecological parameters, this ecosystem was at an immature stage.(2) Based on the investigations of fishery resources and environment between Autumn2000and Autumn2006, the mass-balance models of the Yangtze River Estuary and adjacent waters ecosystem were constructed during the two periods. The changes of the ecosystem structure and energy flow were compared and analyzed before and after the sluice of the Three Gorges Dam, the impact on the estuary ecosystem discussed. Since the catch of lower trophic level species increased in Autumn2006, the mean trophic level of catch declined from3.37to3.33. Relative mortalities of same diet fish groups had some changes, and fishing mortality rate was higher. The ecological efficiencies during two periods had both high values. The total biomass, system throughput, primary production and net system production of Autumn2006were higher, and the system throughput in trophic level I increased23%than that of Autumn2000. The transfer efficiency of primary producers increased, and the role of detritus in nutrient regeneration decreased. The ascendency in Autumn2006was a little higher than that in Autumn2000, and FML and FCI index was close to Autumn2000. Based on analysis of Odum’s ecological parameters, this ecosystem in Autumn2000and Autumn2006were both in developmental stage.(3) Based on the investigations of fishery resources and environment of the Bohai Sea in1982and1992, the Ecopath models of the Bohai Sea ecosystem during the two periods were constructed by the EwE modeling software. The changes of the Bohai Sea ecosystem structure and fishery resources between ten years were compared and analyzed. The models included17functional groups covering the main trophic flow of the Bohai Sea ecosystem, which were Japanese anchovy, Scaly hairfin anchovy, Japanese Spanish mackerel, other pelagic fishes, small yellow croaker, seabass, benthic fishes, other demersal fishes, zooplankton, phytoplankton, detritus, etc. The results indicated that the total biomass of1992was lower than that of1982, and small sized pelagic fishes have become the main components of the fishery resources in the Bohai Sea in1992, and the proportion was obviously higher than that in1982. The mean trophic level of catch declined in1992. The Bohai Sea ecosystem in1982and1992were both in developmental stage, and the system scale in1982was greater than that in1992. From1982to1992, the changes of the Bohai Sea ecosystem structure were mainly due to the decrease of primary production and increase of fishing pressure. Since there was high surplus production, the recovery of depleted fishery stocks and increase of fishery resources may be possible and high potential if the rational conservation measures were applied. (4) Using1982Bohai Sea model as the starting status, an Ecosim model was constructed in Bohai Sea, including the same functional groups. This model simulated the dynamic changes in different development stages of Bohai Sea ecosystem, and the fishing impact on this ecosystem, using CPUE and relative fishing effort time series to drive this model. From1982to2008, the biomass of mantis shrimp retained increasing, the biomass of main economical fishes decreased, including small yellow croaker, Japanese spanish mackerel, Japanese anchovy, seabass and scaly hairfin anchovy, and the biomass of shrimps, crabs and cephalopods relatively stabilized. The mean trophic level of catch declined obviously from1982to2008, and had notably negative correlation with the total catch. FIB index had the same change trends with the total catch, increasing after1984. Q-90diversity index was in a state of fluctuation from1982to1987, maintaining growth trend from1988tol994, followed by a rapid decline after1994, from2.5to around0.5, and ecosystem biodiversity declined. Compared start state (1982) with end state (2008) of the model, the maturity of ecosystem decreased. Overfishing resulted in the degeneration of ecosystem and the decline of the total biomass level.(5) Based on the data of surveys of fishery resources and environment from2009to2010, an Ecopath mass-balance model of the Laizhou Bay ecosystem was constructed, including26functional groups. This study analyzed the summary statistics parameters of the ecosystem, mixed trophic impacts and keystone species, and calculated the ecological carrying capacity of Chinese shrimp enhancement by Ecopath model. The ecosystem attributes statistics:the total primary production/total respiration (TPP/TR) and total primary production/total biomass (TPP/B) was1.53and24.54, respectively, together with low Finn’s cycling index (0.07), high surplus production being434.41t-km-2yr-1and low system connectance index (0.29), indicating that this ecosystem was at an early development stage according to Odum’s theory. Moreover, the analysis on the keystone species showed that Chinese shrimp was not a keystone species of this ecosystem. Current biomass of Chinese shrimp was0.1143t-km2, and Chinese shrimp has potential for continued enhancement. The biomass of Chinese shrimp could be increased25.8times without exceeding the ecological carrying capacity of2.9489t-km-2.更多还原