基于Ecopath模型的瓯江口斑鰶、刀鲚和鮻的增殖生态容量评估

Ecological carrying capacity of Konosirus punctatus, Coilia nasus, Liza haematocheila of stock enhancement in Oujiang estuary based on Ecopath model

摘要:

目的 基于Ecopath模型对瓯江口斑鰶、刀鲚和鮻增殖生态容量进行评估。方法 根据2021年3月、5月、8月和11月瓯江口渔业资源与生态环境本底调查数据，通过构建由24个功能组组成的瓯江口Ecopath 模型，对瓯江口营养级结构和能量流动进行初步分析，并估算了斑鰶、刀鲚和鮻的增殖生态容量。结果 瓯江口海域营养级范围为1.00~3.55，其中斑鰶的营养级为2.46，刀鲚的营养级为2.97，鮻的营养级为2.44，均属于较低营养级。系统总初级生产力/总呼吸量(TPP/TR)为2.276，系统连接指数(CI)为0.367，系统杂食性指数(SOI)为0.217。斑鰶、刀鲚和鮻的现存生物量分别为0.0189 、0.0379 和0.0055 t/km²，根据模型估算的生态容量分别为0.070、0.065和0.132 t/km²。结论 该生态系统中有大部分营养物质未被利用，初级生产力利用效率低，系统成熟度不高；对比当前状态与模拟放流后系统状态，系统的TPP/TR、CI和SOI均无较大变化，即斑鰶、刀鲚和鮻具有较大增殖放流潜力。

Abstract:

Ecological capacity assessment is an important prerequisite for fishery resource restoration and conservation. Based on the survey data of the Oujiang estuary fishery resources and ecological environment survey in March, May, August and November 2021, the Ecopath model consisting of 24 functional groups was constructed to analyze the trophic level structure and energy flow and calculated the ecological carrying capacity for Konosirus punctatus, Coilia nasus and Liza haematocheila. The results showed that the trophic level of the Oujiang estuary ecosystem ranged from 1.00 to 3.55, the trophic level of K. punctatus (2.46), C. nasus (2.97) and L. haematocheila (2.44) were lower than other fish. The evaluation of the ecosystem structure and function showed that the total primary production/total respiration (TPP/TR) was 2.276, connectance index (CI) and system omnivory index (SOI) were 0.367 and 0.217, respectively. The results indicated that most of the trophic in the ecosystem were not utilized, the primary productivity utilization efficiency was low, and the system was still immature. The current ecological carrying capacity for K. punctatus, C. nasus and L. haematocheila was 0.0189, 0.0379 and 0.0055 t/km², and the potential ecological carrying capacity, based on the Ecopath model, was estimated at 0.070, 0.065 and 0.132 t/km². When reaching the ecological carrying capacity, the TPP/TR, CI and SOI changed marginally. The stability and structure of the ecosystem of Oujiang estuary were not altered significantly, the system has a potential for continuous enhancement.