基于Ecopath模型的景观湖泊生态重建成效评价

Evaluation of ecological reconstruction effectiveness of landscape lakes based on Ecopath model

为评估西南地区某景观湖泊运用清水型生态系统方式构建的水体修复工程的成效,依据恢复3年后湖泊生态环境调查数据,构建了景观湖泊的Ecopath模型,分析了修复后湖泊的水质变化、新形成的食物网结构、营养级间的能量流动以及生态系统的成熟稳定度,并探究提升修复效果所能采取的人工干预措施。模型共包括肉食性鱼类、鲤、鲫、鲢、鳙、草食性鱼类、浮游动物、浮游植物、沉水植物等16个功能组,基本包括了此生态系统能量流的全过程。结果显示,景观湖泊Ecopath模型Pedigree指标值为0.546,可信度较高。景观湖泊生态系统的营养级为1~3.092,总能量转换效率为1.648%,较为低下。净初级生产量与总呼吸量的比值(TPP/TR)为1.946,连接指数(CI)为0.280,系统杂食指数(SOI)为0.052,Finn's循环指数(FCI)和Finn's平均能流路径长度(FML)分别为5.079%和2.383,与修复前相比,景观湖泊的食物链初步恢复。结合生态通道模型综合分析发现,此景观湖泊修复后仍是一个稳定性较低、食物网联结程度简单、抗外界干扰能力弱且处于发育早期的不成熟生态系统。清水型生态系统构建模式仍需要后期人为干预和调控。

To evaluate the effectiveness of freshwater-based ecological restoration measures employed in a landscape lake in the Southwest region of China and explore potential human interventions to enhance the restoration outcomes,a study was conducted using ecological survey data collected three years after the lake restoration project.As per the essence of the survey findings,an Ecopath model was constructed for the landscape lake,enabling an analysis of the variations in water quality,the newly formed structure of the food web,the flow of energy among trophic levels,and the maturation and stability of the ecosystem after the transformation.The Ecopath model encompassed a total of 16 functional groups,including piscivorous fish,carp,crucian carp,silver carp bream,herbivorous fish,zooplankton,phytoplankton,and submerged aquatic plants,covering the entire energy flow process within this ecosystem.The results indicated a P index of 0.546 for the landscape lake Ecopath model demonstrating a substantial level of reliability.The trophic levels within the lake ecosystem ranged from 1 to 3.092with an overall energy transfer efficiency of 1.648%,which was considered relatively low.The ratio of net primary production to total respiration (TPP/TR) was 1.946,the connectivity index (CI) was 0.280,the system omnivory index (SOI) was 0.052,and Finn's cycling index (FCI) and Finn's mean path length (FML) were 5.079%and 2.383respectively.These figures showed a preliminary recovery of the food chain within the landscape lake compared to its pre-restoration state.By integrating the comprehensive analysis of the ecosystem connectivity model,it was revealed that the landscape lake exhibited characteristics of a relatively unstable,less connected food web,with limited resilience to external disturbances,suggesting an immature ecological system in its developmental stage Therefore,future human intervention and regulation are still required for the freshwater-based ecosystem construction model to reach its full potential.