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1.
本研究根据2020年11月,2021年1月、4月及8月在崇明岛周边海域的渔业调查数据,使用开源程序Rpath构建了包括22个功能群的物质平衡模型,对该海域生态系统结构和特征进行研究。结果表明：崇明岛周边海域生态系统各功能群营养级范围为1～4.32。小型底栖生物的生态转换效率最低（0.01）,说明其到高营养级的能量转换存在瓶颈,是影响该海域底层食物链营养传递效率的关键节点。生态系统总体特征分析表明,该生态系统总规模为2 909.42 t/(km2·a),低于附近海域生态系统规模。浮游植物对生态系统总初级生产力的贡献为60%,是该生态系统的主要营养来源。生态系统总初级生产量/总呼吸量为1.99、系统杂食性指数为0.18,表明生态系统成熟度较低,食物网简单,受干扰后恢复能力较差。模型敏感性分析表明,功能群生物量是影响模型输出准确程度的主要指标。本研究结果可以为该海域生态系统水平的禁捕效果评估工作提供基准参考。 相似文献
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为构建1985～1986年长江口生态系统的Ecopath模型, 作者根据1985～1986年全年12个航次长江口及邻近海域综合调查数据, 分析此历史时期长江口及邻近海域生态系统的能流结构, 并对生态系统总体特征进行了综合评估。1985～1986年长江口水域生态系统包括16个功能群, 各功能群的营养级在1～4.52, 中上层游泳生物食性鱼类占据最高营养级。各功能群间关系主要由3种途径导致: 控制类型、生态位重叠和营养级联。营养级聚合分析表明, 1985～1986年长江口生态系统能流中牧食食物链占据主导地位, 直接来自初级生产者的占比57%。此历史时期长江口生态系统各营养级平均转化效率为12.4%, 其中来自碎屑的能流转换效率为12.9%, 来自初级生产者的转换效率为12%。生态系统总体特征分析显示, 该历史时期连接指数和系统杂食指数分别为0.471和0.103, 长江口及邻近海域循环指数和平均路径长度分别为9.35%和2.778, 总初级生产量/总呼吸量为1.724。 相似文献
3.
本文根据2004年长江口及其邻近海域生态调查数据,运用生态通道模型(Ecopath模型)构建生态系统能流网络,分析本区域生态系统营养结构及功能,并与1985—1986年研究数据进行对比,解析两个时期生态系统营养结构与功能的差异。研究结果显示,2004年长江口及其邻近海域生态系统营养级范围为1～4.34,相较于1985—1986年研究结果,底层无脊椎动物食性鱼类和头足类的营养级变动较大。牧食食物链占据主导地位,浮游植物在浮游动物和水母的能量来源中所占比例均在60%以上;碎屑食物链所占能流比为44%。系统总能流为6342.081 t·km–2·a–1。渔获物平均营养级下降,生态营养效率平均值较高,但是碎屑和浮游植物的生态营养效率却明显下降,碎屑趋于累积。生态系统统计量整体显示,长江口及邻近海域生态系统成熟度降低。 相似文献
4.
基于2018年海州湾及邻近海域的渔业资源底拖网调查数据，运用Ecopath with Ecosim 6.5 (EwE)软件构建由26个功能群组成的海州湾及邻近海域生态系统Ecopath模型，对现阶段该生态系统的营养结构、营养相互关系和系统总特征等进行分析，旨在为实施基于生态系统的渔业管理提供理论依据。结果表明:海州湾及邻近海域生态系统各功能群的营养级范围为1.00～4.19，其中鱼类营养级范围较广，为3.22～4.19；浮游动物和其他软体动物受初级生产者和捕食者的双重作用，处于重要的营养位置；生态系统总体特征分析显示，该生态系统的总初级生产量与总呼吸量的比值为7.096，总初级生产量与总生物量的比值为56.866，系统的连接指数和系统杂食指数分别为0.429和0.204，说明该生态系统目前处于不成熟、不稳定的状态，容易受外界扰动的影响。本文通过对海州湾及邻近海域生态系统模型进行研究，解析了该海域营养结构和系统发育状况，将为海州湾渔业资源的可持续利用和科学管理提供理论依据。 相似文献
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为改善热带珊瑚岛礁型海洋牧场的珊瑚礁生境,实现生物资源的养护和渔业资源的产出功能,在对海参等高值经济种开展底播增殖前,科学评估其生态容量是防止引发海洋牧场生态风险的重要保证。运用生态系统模型法评估了三亚蜈支洲岛热带珊瑚岛礁海洋牧场花刺参(Stichopus monotuberculatus)的底播增殖容量。根据2020~2021年蜈支洲岛海洋牧场近岛区渔业资源调查与环境因子数据,运用Ecopath with Ecosim 6.6软件构建了该海域的生态系统营养通道模型。研究表明:生态系统各功能组营养级范围介于1~3.52,系统的食物网结构以牧食食物链为主,总能流中有43%的能量来源于碎屑功能组,其在系统总能流中有重要地位。系统的总平均能量传递效率为9.353%,略低于林德曼能量传递效率(10%)。总初级生产量/总呼吸量为3.726,总初级生产量/总生物量为28.834,系统连接指数为0.256,杂食性指数为0.120,系统Finn''s循环指数和平均路径长度分别为2.485%和2.379,表明近岛区生态系统食物网结构较为简单,且系统稳定性和成熟度偏低,易受外界干扰。根据模型评估的花刺参增殖生态容量为110.21 t/km2,是现存量的206 倍,有较大增殖空间,并且达到生态容量后碎屑组的能量再循环利用效率将显著增加,营养级结构能得到进一步优化,系统稳定性及成熟度将有所提高。基于研究结果,可适当采捕与花刺参生态位相近的生物,同时增殖放流其他处于不同营养层次的经济种,从而减少种间竞争,有效利用系统冗余能量,进而扩大花刺参的生态容量,实现海洋牧场的健康可持续发展。 相似文献
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南极大磷虾（Euphausia superba）为南大洋生态系统中的关键种，也是南极生态系统食物网中的重要枢纽。该种秋冬季转换期的营养信息对于理解其知之甚少的越冬机制非常重要。但关于此方面的少数研究在时空变化上仍存在着差异。为此，我们调查了南极半岛秋季（4-5月）和冬季（6月）磷虾成体δ13C和δ15N值的个体、月份及区域性差异。我们的目标旨在检验该期间磷虾的营养变化以及磷虾与其在南极海洋生态系统中的摄食环境之间的关系。结果如下：（1）磷虾δ13C值与体长之间无显著关系，但δ15N值与体长之间则存在显著相关性；（2）秋季磷虾δ13C值呈现增长趋势，但冬初季节并无显著变化，此期间δ15N值无显著不同；（3）布兰斯菲尔德与南设得兰群岛之间的δ15N平均值显著不同。我们的数据表明南极半岛秋至初冬转换期间磷虾成体营养呈现个体、季节性及区域性变化。 相似文献
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构建了包括20个功能组的西南黄海生态通道模型(Ecopath Model)。分析结果表明:各功能组营养级的范围在1. 000～4. 509之间,鸟类、鱼类、头足类等主要高营养级生物的营养级范围为3. 417～4. 509。该生态系统的能量流动主要发生在食物网的低营养级部分,在7个系统整合营养级间,能量传递效率沿食物链逐级降低,各营养级生物的消耗量和产出量也急剧减少。从第I营养级到高营养级间的逐级转换效率分别为11. 33%、13. 16%、15. 50%、14. 67%、13. 61%和15. 68%,系统平均转化效率为13. 22%;来源于碎屑的能量转化效率为13. 35%,来自初级生产者的转化效率为13. 14%。在总能流中,直接来自碎屑的占43%,来自初级生产者的占57%,说明系统的能流通道以牧食食物链为主导。混合营养评价显示,系统生产者碎屑与浮游植物对其他多数功能群有积极影响,蟹类、鲽形目、水母、大型底栖和浮游生物中同类竞争的消极影响尤为明显。西南黄海生态系统总初级生产力与总呼吸量比值为2. 541,Finn’s循环指数和Finn’s循环路径长度分别为3. 983、2. 444。通过模型输出的系统生态参数分析,当前西南黄海生态系统仍处于不成熟的、不稳定的阶段。 相似文献
8.
大洋性鱿鱼的洄游路径能够给我们重要的信息，帮助我们了解其时空分布的变化。标记-重捕和电子标记方法在施行过程中仍存在一些问题。头足类的硬组织，如角质颚，有着稳定的形态特征和类似耳石的连续生长纹，同时包含丰富的生态信息，可以为我们研究物种的时空分布提供相关信息。本研究中，我们以北太平洋柔鱼为研究对象，基于不同角质颚生长阶段进行取样来重建鱿鱼的洄游路径。研究结果认为，通过电感耦合等离子质谱仪（LA-ICP-MS）取样，发现角质颚的喙端矢状平面（RSS）检测到9种微量元素。针对上述几种元素，发现不同生长阶段的磷（P）、铜（Cu）和锌（Zn）存在显著差异。利用钠（Na）、磷和锌与海表面温度（SST）建立线性回归模型。基于贝叶斯模型，计算出不同时期柔鱼出现的较高概率的海域。结合不同时期的高概率分布海域，建立起柔鱼的洄游路径，该结果与前人研究结果一致。本研究也证实了角质颚可以为研究大洋性柔鱼的洄游路径提供有效的信息。 相似文献
9.
基于延绳钓观察员数据的热带太平洋中东部食物网拓扑结构分析 总被引：1，自引：0，他引：1
热带太平洋是金枪鱼类、旗鱼类等渔业的主要作业海域，但目前针对此海域食物网的研究仍十分缺乏。本文根据2017年6月-11月中国金枪鱼科学观察员在热带太平洋中东部海域（13°09''N -34°27''S, 100°03''-176°17''W）采集的鱼类样品，结合胃含物及其他分析方法以35个物种间的摄食关系为基础对此海域的食物网结构进行了分析。拓扑学指标（节点强度，D；中心性指数，BC和CC；拓扑重要性指数，TI1和TI3；关键性指数，K、Kt和Kb）和Key-Player算法（KPP-1和KPP-2）用来筛选关键种，并结合体长数据建立了基于关键种的简化食物网。肯德尔相关性分析和聚类分析结果表明，不同拓扑学指标筛选出的关键种是一致的。大多数关键种与太平洋其他海域的研究结果是相同的，如剑鱼（Xiphias gladius）、长鳍金枪鱼（Thunnus alalunga）、小吻四鳍旗鱼（Tetrapturus angustirostris）头足类和鲭属。移除5个关键种后，食物网将被离散为许多互不连接的部分（F=0.632，FD=0.795，RD=0.957），表明这些物种在维持食物网结构和稳定性中的必要性。物种体长是本研究构建简化食物网时的决定性因素。研究结果有助于提高对热带太平洋食物网结构的认识，同时为进一步的生态系统动力学研究提供科学依据。 相似文献
10.
以三疣梭子蟹(Portunus trituberculatus)、凡纳滨对虾(Litopenaeus vannamei)和梭鱼(Liza haematocheli)混养池塘生态系统为研究对象,利用Ecopath with ecosim(EwE)模型软件,构建了由17个生物功能组组成的能量流动模型。研究表明,系统由5个营养级组成,其中第Ⅰ、Ⅱ营养级的能量流通量占系统总能量流通量的比例分别为63.47%和35.39%。系统大部分消费者位于营养级Ⅱ左右,食物链结构多呈"线状"。系统总能量流中碎屑功能组占74.58%,初级生产者占25.42%,其中,碎屑功能组中的人工饵料生物能占系统总能量来源22.31%,在系统总能量流中起重要作用。系统Finn’s循环指数(FCI)为21.24%,连接指数(CI)和系统杂食指数(SOI)分别为0.28和0.06,相对聚合度(A/C)为0.45。从生态营养学效率(EE)值来看,系统对来自碎屑功能组的能量利用率较高,对来自初级生产者微型、微微型浮游植物的能量利用效率较低。大量初级生产者能量未被利用而直接流向碎屑功能组,表明该系统的营养级结构还能进一步优化。建议提高梭鱼的放养密度或引入合适的滤食性生物进行搭配养殖,进一步提高系统的能量利用效率和混合养殖效益。 相似文献
11.
应用物质平衡模型模拟一个半封闭海湾的营养结构和能流特征 总被引：4，自引：1，他引：3
The marine ecosystem of the Jiaozhou Bay has degraded significantly in fisheries productivity and its ecological roles as spawning and nursery ground for many species of commercial importance has been declining in recent years. A mass-balanced trophic model was developed using Ecopath with Ecosim to evaluate the trophic structure of the Jiaozhou Bay for improving ecosystem management. The model were parameterized based on the fisheries survey data in the Jiaozhou Bay in 2011, including 23 species groups and one detritus group according to their ecological roles. The trophic levels of these ecological groups ranged from 1(primary producers and detritus) to4.3(large demersal fishes). The estimated total system throughput was 12 917.10 t/(km~2·a), with 74.59% and25.41% contribution of the total energy flows from phytoplankton and detritus, respectively. Network analyses showed that the overall transfer efficiency of the ecosystem was 14.4%, and the mean transfer efficiency was 14.5%for grazing food chain and 13.9% for detritus food chain. The system omnivory index(SOI), Finn's cycled index(FCI) and connectance index(CI) were relatively low in this area while the total primary production/total respiration(TPP/TR) was high, indicating an immature and unstable status of the Jiaozhou Bay ecosystem. Mixed trophic impact analysis revealed that the cultured shellfish had substantial negative impacts on most functional groups. This study contributed to ecosystem-level evaluation and management planning of the Jiaozhou Bay ecosystem. 相似文献
12.
Quantitative model of trophic interactions in Beibu Gulf ecosystem in the northern South China Sea 总被引：2，自引：2，他引：2
1IntroductionThe Beibu Gulf is a natural semiclosed conti-nental sea of the South China Sea,which is situatedat17°00′~21°45′N,105°40′~110°10′E,and sur-rounded by China and Vietnam(see Fig.1).It hasa subtropic monsoon climate with an average winter 相似文献
13.
Changes in trophic flows and ecosystem properties of the Beibu Gulf ecosystem before and after the collapse of fish stocks 总被引：1，自引：0，他引：1
Mass-balance models (Ecopath) of the ecosystem before and after collapse (1959-1961 and 1997-1999) of fish stocks were developed with Ecopath software to compare the differences in ecosystem structure, functioning and ecosystem properties of the Beibu Gulf. The model includes 20 functional groups consisting of commercial important fish groups and other ecologically important groups in the ecosystem such as zooplankton, phytoplankton, and detritus. Results indicated that biomass and catches of the system have changed drastically between the 1960s and 1990s, especially for the high trophic levels (TL). The biomass of level V in the early 1960s was 32 times higher than that of the late 1990s, however, the biomass of level I and II in the 1990s was higher than the 1960s. Despite the higher catches in the 1990s, fishing was ecologically less expensive during the 1990s than 1960s due to small fish catches were large. Mean transfer efficiency decreased from for 10.2% in the 1960s to 9.1% in the 1990s periods. According to the summary statistics, the parameters of net system production (NPS) and total primary production to total respiration ratio were increased from 1.013 in the 1960s to 2.184 in the 1990s, however, the connectance index (CI), system omnivore index, Finn’s cycling index and mean path length decreased from the 1960s to the 1990s. The overhead (O) was higher in the 1990s model while the ascendancy (A) decreased nearly 10% in the 1960s. The ‘Keystoneness’ result indicate that zooplankton was identified as keystone species in 1960s, however, the elasmobranches was keystone species in the late 1990s. The average trophic level of the fishery decreased from 3.32 in the 1960s to 2.98 in the 1990s, and exhibits classic symptoms of “fishing down the food web”. All the indices of the system attributes suggests that the Beibu Gulf ecosystem in 1960s was found to be more mature than in the 1990s due to the collapse of demersal ecosystem, and the ecosystem changed from being dominated by long-lived, high trophic level groundfish dominated system toward a system with small-size and low-value species over fifty years. 相似文献
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根据2021年渔业资源调查数据构建了含有23个功能组的舟山海域生态系统Ecopath模型,分析了当前舟山海域生态系统总体特征并估算了褐菖鲉在舟山海域的生态容量。结果表明:舟山海域生态系统营养级范围为1.000 (浮游植物和有机碎屑)～4.277 ( 鳐类),石首鱼科、虾类和 鳐类为舟山海域生态系统中的关键种。碎屑食物链和牧食食物链是舟山海域生态系统主要的食物链。碎屑和浮游植物对食物网的贡献率分别为61.32%和38.69%。始于浮游植物和碎屑的营养传递效率分别是9.34%和10.50%,系统总营养传递效率是9.82%。总初级生产量/总呼吸量为2.26,系统连接指数为0.372,系统杂食性指数为0.222。生态系统总体特征反映了舟山海域生态系统的成熟状态较低,生态系统处于不稳定阶段,容易受到外界环境变化的影响。根据模型估算,当褐菖鲉生物量增加至8.6倍时,褐菖鲉达到生态容量0.007 95 t/km2,此时生态系统仍保持平衡,且生态系统总体特征基本稳定。因此,褐菖鲉在舟山海域尚有较大增殖潜力。 相似文献
15.
S. Manickchand-Heileman L.A. Soto E. Escobar 《Estuarine, Coastal and Shelf Science》1998,46(6):885-899
A preliminary mass-balance trophic model was constructed to determine the flow of energy in a community of fish and invertebrates on the continental shelf of the south-western Gulf of Mexico. Input parameters were taken from the literature, except for the biomass of fish groups which was obtained from trawl surveys in the study area. The model consists of 12 fish groups, five invertebrate groups, phytoplankton and detritus. Results indicate an imbalance between primary production and consumption, with only about 10% of primary production being consumed in the water column. Most of the primary production is exported to detritus which forms the basis of the food-web, with a detritivory/herbivory ratio of 2·5. Benthic invertebrates play a significant role in transferring energy from detritus to higher trophic levels. Eight discrete trophic levels were found, with very reduced flow at levels higher than the fifth. The highest fractional trophic level is 4·3, and consists of sharks. Analysis of mixed trophic impacts showed that detritus and lower trophic levels have a significant positive impact on other groups in the system. Mean transfer efficiency is 9·2%. Some whole system properties are also given. Of net primary production, 6·7% is required to sustain current catch levels, suggesting that the resources in this area are fully exploited. 相似文献
16.
海洋大型底栖动物群落次级生产力估算模型研究进展及应用评价 总被引：1，自引：0，他引：1
大型底栖动物是海洋生态系统的重要组成部分,在生态系统物流和能流中占有重要地位。定量估算海洋大型底栖动物次级生产力在其功能研究中具有重要意义。本文综述了海洋大型底栖动物次级生产力估算模型研究的3个阶段:起步阶段(1979-1990)、发展与完善(1990-2001)、成熟并广泛应用(2001-至今)。国内关于海洋大型底栖动物次级生产力估算基本都采用Brey(1990)经验公式,采用经验公式的方式可分为3类:逐种计算、按站位计算和按类群计算,逐种和按类群计算最符合Brey(1990)给出的参考步骤。不同方法估算同一海域次级生产力结果不同,同一估算方法估算不同生境不同群落次级生产力结果偏差也不同。今后的工作应注重种群次级生产力研究,积累大量基础数据,以便建立适宜我国特定海域的大型底栖动物次级生产力估算模型。 相似文献
17.
Evaluation of the Effect of Marine Ranching Activities on the Tongyeong Marine Ecosystem 总被引：1，自引：0，他引：1
Using ecosystem models (Ecopath, Ecosim, and Ecospace), we assessed the structure and function of the Tongyeong marine ranching ecosystem and compared changes in various ecosystem components before and after marine ranching activities. An ecosystem structure model, Ecopath, was used to estimate the changes in biomass and trophic level of major species or groups, the relative contribution of target species or groups to the total flow of energy (throughput), and niche overlaps and impacts of competition between major species or groups. It showed that the Tongyeong ecosystem had 4 trophic levels. A large amount of energy flows occurred at trophic levels 3 and 4, and jacopever rockfish (Sebastes schlegelii) and black rockfish (S. inermis) that were target species for stock enhancement belonged to trophic level 3, indicating that those two species played an important role in the ecosystem. Using an ecosystem dynamic model, Ecosim, the mechanism of dynamic changes in the quantity of target species or groups was investigated to identify the effects of stock enhancement activities and impacts of fishing intensity. After marine ranching activities, the biomass of two target species had increased, while those of most other fish groups decreased. Assuming that fishing mortality was double the current level, the biomass of most fish groups decreased but jacopever rockfish maintained its current stock level due to excessive stock enhancement and low fishing mortality in recent years. An ecosystem space model, Ecospace, was employed to simulate the temporal and spatial dynamics of the biomass of organisms in order to examine how resource enhancement activities have changed the distribution and abundance of target species or groups in the ecosystem. The distribution pattern of jacopever rockfish and black rockfish showed stronger aggregations around reefs and rocky areas with high stock densities after ranching. However, most of the other fish groups exhibited lower densities in the marine ranching area, while they showed higher densities outside the marine ranching area. Thus, it would be necessary to take appropriate holistic management actions based on the ecosystem-based approach to keep the ranching ecosystem healthy and to maintain the fishery production of the ecosystem at the maximum sustainable level. 相似文献
18.
A 26-compartment steady-state trophic model (1997–1999) was constructed using the Ecopath with Ecosim software to study the general status and development trends of the Pearl River Delta coastal ecosystem. The results show that the values of effective trophic level ranged from 1.00 to 4.21. It was found that a high trophic niche overlap existed in the typical estuarine ecosystem. Mixed trophic impacts show that detritus and the groups at the low trophic levels had positive influences on most groups. The ecosystem was found to be in an immature state during 1997–1999 based on the system statistics. 相似文献