基于Ecopath模型的祥云湾海洋牧场生态系统结构和能量流动分析

Analysis of ecosystem structure and energy flow in Xiangyun Bay marine ranching based on Ecopath model

为了对河北省祥云湾海域国家级海洋牧场区生物群落结构和能量流动过程进行量化分析,基于2020年对祥云湾海洋牧场区和对照区4个季节的生物资源调查数据,构建了海洋牧场区及对照区生态通道模型(Ecopath),其中,海洋牧场区模型包含功能组21个,对照区包含18个。结果表明:海洋牧场区分数营养级为1~4.04,对照区为1~4.35,两个区处在食物链顶端的分别为头足类和许氏平鲉(Sebastes schlegelii);生物群落间的能量流动主要集中在较低营养级,能量传递效率沿食物链逐级降低,海洋牧场区第1、2、3营养级的能量流通量占系统总能量流通量的比例分别为58.09%、38.73%和2.82%,对照区分别为72.93%、24.25%和2.41%;海洋牧场区来自碎屑功能组和初级生产者功能组的物质数量占系统总物质来源的比例分别为37.7%、62.3%,对照区分别为39.6%、60.4%,海洋牧场区生物群落的能量流动通道受到牧食食物链主导更为明显,海洋牧场区系统连接指数(CI)和杂食指数(SOI)分别为0.34、0.24,对照区分别为0.30、0.21,海洋牧场区与对照区系统的香农威纳多样性指数(SDI)分别为1.86、1.47。研究表明,相较于对照区,海洋牧场区的生态系统成熟度更高,食物网结构更为复杂,系统内部稳定性更高。

To quantitatively analyze the biocommunity structure and energy flow process in the marine ranching area,the Ecopath Model was constructed based on the 4 voyages survey of biological resources by a 99 kW fishing vessel with 3 cm mesh bottom trawl in Xiangyun Bay Marine Ranching Area,and control area in 2020.There were 21 functional groups in the marine ranching area model,and 18 functional groups in the control area.The model analysis showed that the trophic level range was varied from 1 to 4.04 in the marine ranching area,with Cephalopod at the top of the food chain and from 1 to 4.35 in the control area,with black rockfish(Sebastes schlegelii) at the top of the food chain.The energy flow between communities was mainly concentrated at the lower trophic level,and the energy transfer efficiency was decreased gradually along the food chain.The proportion of the energy flux was found to be 58.09%,38.73% and 2.82% at trophic level 1,2 and 3 in the total energy flux in the marine ranching area,respectively,and 72.93%,24.25% and 2.41% in the control area was.The proportion of energy in the total energy source of the system was 37.7% from detritus functional group and 62.3% from primary producer functional group in the marine ranching area,and 39.6% from detritus functional group and 60.4% from primary producer functional group in the control area.The energy circulation channel of the marine ranching community was more dominated by grazing food chain.The system connectivity index(CI) was 0.34 and system omnivore index(SOI) 0.24 in the demonstration area,0.30 and 0.21 in the control area,respectively,with Shannon Weiner diversity index(SDI) of 1.86 in the demonstration area and of 1.47 in the control area.The analysis of the output parameters of the model revealed that the establishment of marine ranching area made the marine biological community structure gradually a stable trend.