【作者】 杨再福；

【导师】 陈立侨； 陈勇；

【作者基本信息】 华东师范大学 ， 动物学， 2003， 博士

【摘要】 Viily Christensen,Carl J.Walters,Daniel Pauly and Polivina创立的Ecopath with Ecosim软件，该软件由众多模型组合而成，并加入许多生态学分析方法，能广泛应用于水生生态系统的定量分析，特别是渔业管理与政策模拟，并可用于比较不同时期生态系统的时空动态变化，定量评估水生生态系统能量流动过程的一种营养平衡模型，该模型已在全球100多个水生生态系统中得到应用(Christensen,V.,C.J.Walters,and D.Pauly.2002)，是目前渔业和水生生态系统定量分析最全面与权威的软件之一。目前国内有关Ecopath with Ecosim软件在淡水生态系统中的研究还末见报道，本研究在Ecopath with Ecosim软件的基础上建立太湖渔业与生态系统的Ecopath模型，对太湖生态系统进行了定量的分析与模拟，对渔业小型化的发展，渔业政策评估与优化，渔业与环境的相互影响和渔业与环境可持续发展进行了相应的评价，并提出了科学的管理对策。主要结果如下： (1)为了更好地对太湖生态系统进行定量性分析，将太湖渔业生态系统分成了19个功能组，在输入每一个功能组的B、P/B、Q/B或EE的基础上，输入每一功能组的食物组成、净迁移率、渔业捕捞量，渔业价格与利润等相应的参数后，运用Ecoranger对系统进行平衡调试，当系统达到最终平衡并与实际情况相吻合后，输出生态营养流动效率、各功能组的营养级和混合营养影响、不同营养级之间的能流来源与营养流动关系，功能组的死亡率组成以及系统的总体特征。 (2)太湖生态系统中生产者和碎屑的能量转换效率分别为10.3％和10.4％，整个生态系统的能量转换效率为10.4％。系统的杂食系数为0.186，系统的总净初级生产力4520.11t/km~2/year，总P/B系数为9.926。 (3)渔业小型化与个体小型化是目前所面临的全球性问题，太湖渔业小型化经历了未小型化、初步小型化到完全小型化的发展过程，小型鱼类占渔业总产量的比例不断上升，小型渔业成为太湖渔业的主导主要是人类的不合理开发与利用的结果。运用Ecopath with Ecosim软件模拟了太湖渔业小型化的发展过程及中文摘要原因，小型渔业比例的上升与大中型渔业比例的下降的关系。人工放流比例的增加、封湖禁渔时间的延长，繁殖保护区的扩大、捕捞努力量的下降、沉水植物的恢复是控制渔业小型化的主要措施。太湖渔业捕捞产量呈不断上升的趋势，过度捕捞导致太湖渔业捕捞营养级的下降，1952一1958年、1973一1978年和1979一2000年太湖捕捞营养级的平均值分别为3.29、3.26和3.07，渔业导致营养级在近50年内下降了0.23。1964年至1981年太湖翘嘴红舶的渔业营养级下降0.33。捕捞产量的增加导致渔业营养级下降。 (4)渔业总产量与湖水CODMn，刀跻和虾类产量与湖水TN/TP，富营养化指数(TSI)与渔业总产量和刀鱿的产量之间具有显著相关，并建立相应的回归方程。太湖富营养化加重与渔业总产量的增加，渔民人均收入的提高和经济发展是相一致的。 (5)在Ecopath平衡模型的基础上，建立渔业发展与生态系统基本吻合的Ecosim模型，然后进行渔业政策变化的模拟与分析，得出1 973一2000年的模拟结果与生态系统的实际情况相吻合，在保持2000年捕捞强度，对2001一2030年渔业产量与生物量进行了预测模拟。对1952一2000年太湖主要渔业政策进行了相应的Ecosim模拟与评估，不同捕捞强度对各功能组的生物量及产量的影响，在没有封湖禁渔政策的条件下，太湖渔业生态系统各功能组的生物量与产量的变化，探讨了主要渔业政策的发展对渔业生态系统的定量性风险分析。在设置渔业经济和社会目标的基础上，在生态系统的结构保持相对稳定的条件下，对渔业政策进行了优化选择，并在优化的渔业政策下对整个生态系统的生物量和渔业产量进行了相应的模拟分析，调整捕捞渔船的相对大小。 (6)1 952一1962年太湖单位捕捞努力量的渔获量(CPUE)总体上呈不断上升趋势，到1979年达到近50年来的最高点。1979年之后开始大幅度下降，至1994年，太湖的CPUE下降为近50年来的最低水平，仅为0.24，相当于最高年份的10%，过度捕捞导致渔业资源遭到了严重破坏。经过对捕捞产量的时间序列分析发现，1 952一1978年，太湖渔业基本处于渔业发展的开发阶段，1978一2000年，渔业从开发阶段过渡到成熟阶段，并走向衰退。通过对渔业资源可持续利用的灰色相对关联评价表明，1981一2000年太湖渔业资源资源的可持续利用能力越来越低，资源已到不可持续利用阶段。 一3一中文摘要 总之，以上所述，本研究首次进行了我国淡水生态系统与渔业发展的定量风险分析，并运用Ec叩ath with Ecosim等软件和新的方法对渔业政策，渔业小型化发展与对策，渔业资源与环境的可持续发展进综合评估。建立了湖泊生态系统的健康评价标准，评估了不同健康水平下渔业产量的环境容纳量，进行了湖泊渔业发展与环境之间的相互影响的定量性分析，为湖泊渔业与环境的可持续发展和利用提供了科学的评价标准，同时也为我国和世界淡更多还原

【Abstract】 ECOPATH with ECOSIM is designed for straightforward construction, parameterization and analysis of mass-balance trophic models of aquatic ecosystems. The Ecopath system is built on an approach initially presented by J.J. Polovina for estimating biomass and food consumption of the elements (species or groups of species) of an aquatic ecosystem. Subsequently, it was combined with various approaches from theoretical ecology, notably those proposed by R.E. Ulanowicz, for the analysis of flows between the elements of ecosystems. However, the system has been optimized for direct use in fisheries assessment as well as for addressing environmental questions through the inclusion of the temporal dynamic model, Ecosim, and the spatial dynamic model, Ecospace.The Ecopath with Ecosim software had by late 2000 been distributed to more than 2000 registered users in 120 countries, and more than 100 publications utilizing it have appeared in the scientific literature(Christensen, V, CJ. Walters, and D. Pauly. 2002), Based on Ecopath with Ecosim software, The models of Taihu Lake’s ecosystem was found, The quantitative analysis and simulation were maded in Taihu ecosystem, The small-scale fisheries, fisheries policy and the effect of fisheries and environment were researched and simulated, The sustainable development and countermeasure of fisheries and environment were evaluated and analyzed. The mam results are as follows:(1) In order to quantitative analysis and simulate Taihu ecosystem, 19 groups were separated. B, P/B, Q/B or EE must be input for each group, and input diet composition, net migration, capture yield, fish value and profit before Taihu ecosystem equilibrium tested, Using Ecoranger adjust these parameters in order to fit Taihu ecosystem. After equilibrium, the basic estimate, key indices, mortalitis, consumption were output. Network analysis, cycles and path way may be output straightforward after run.(2) Transfer efficiency of energy from producer and detritus are 10.3% and 10.4% respectively, Transfer efficiency of total ecosystemis is 10.4%. Omnivoryindex of ecosystem is 0.186, Total net primary production is 4520.11 t/km2/year, Total P/B is 9.926.(3) Small-scale fisheries and smaller ivdividual are general because of excess exploitation, Taihu fisheries went through no small-scale fisheries to beginning small-scale and main small-scale fisheries. During 1952-2000, yield and rate of small-scale fisheries were increasing. Using Ecopath with Ecosim software to simulate small-scale fisheries development and reasons, Yield and rate of small-scale fisheries were increasing with bigger fisheries decreasing. Yield and rate of Anchovy were increasing. Rate of stocking fisheries increasing, time of embargo and sloping fishing extend, breeding protect area enlarge, fishing rate decreasing, submerged plant comeback are the main policy control small-scale fisheries development. Because of excess capture, yield were increasing with trophic level decreasing. Average trophic level are 3.29, 3.26 and 3.07 respectively during 1952-1958, 1973-1978 and 1979-2000. Trophic level decrease 0.23 with increasing yield during this 50 years. Trophic level of Erythroculter ilishaeformis decrease 0.33 at 1964 to 1981 .(4) Basic on Ecopath model, Ecosim model of Taihu fisheries was founded during 1973-2000 after adjust some fisheries parameters, the simulation results are very close to reality. During 2001-2030, fisheries yield and biomass of groups were simulated and forecasted when fishing rate retained 2000 year’s level. Main fisheries policy were simulated and evaluated during 1952-2000, Different fishing rate impact on biomass and yield of different group. The change of biomass and yield if there had no embargo and sloping fishing policy was simulated. Quantitative risk analyse and simulate were used to researching main policy change and development. After input fisheries aim and social target, excellent fisheries policy are selected when ecosystem stabilization, Biomass and yield are simulated, amount of更多还原