"6月的数据让人振奋！"岸边，杭州市综合行政执法局（市城市管理局）水设施河道中心的水生生 态监测团队指着记录表感叹道，"浙工大东新关桥断面、半山桥断面共监测到鱼类21种，两个断面单次 采样总量达162尾、总重量超15公斤……这在过去，是难以想象的！" 持续坚守 从单一监测到全面开花 上塘河 清晨，阳光倾泻在上塘河河面，几尾鲢鱼破水而出，银白的脊背在晨光中划出几道晶莹的弧线，又 倏地没入粼粼波光里。 同时，数据显示，鱼类群落个体数量和生物量增加，两个断面采集的渔获物总重达15.62公斤，较 2023年的5.30公斤增长近2倍；渔获物个体数从92尾上升至162尾。不仅如此，多样性指数保持高位， Shannon-Wiener（香农-威纳）多样性指数平均值达2.63，显著高于2023年的1.74，表明物种分布更均 衡、群落结构趋于稳定。 河道监管部门介绍，今年上半年的监测结果显示，市区多个河道的鱼类食性结构日趋完善，涵盖肉 食性、杂食性、滤食性和碎屑食性等多种类型。青梢鲌、蒙古鲌等肉食性鱼类的出现，反映出食物链趋 于完整；鲫鱼、逆鱼等杂食性鱼类作为优势种群保持稳定，成为生态健康的基石；滤食性与碎屑食性鱼 类数量增多， ...

Core Viewpoint - The Yangtze River fishing ban, initiated in 2021 for a ten-year period, has led to a gradual recovery of fish resources and biodiversity, although concerns about community structure imbalance persist [1][3]. Group 1: Fishing Ban Impact - The fishing ban has resulted in increased fish populations in certain areas, attributed to three main factors: limited natural reproduction in closed lakes, seasonal fish aggregation in open waters, and long-term feeding leading to habituation [2][3]. - The Ministry of Agriculture and Rural Affairs indicates that fish resources will remain within the carrying capacity for the foreseeable future, despite the ongoing recovery of biodiversity [3][5]. Group 2: Biodiversity and Monitoring - The 2024 report on aquatic biological resources shows a slow recovery of fish species and diversity, with the integrity index still rated as "poor" [3][5]. - Since the ban, 344 native fish species have been monitored, an increase of 36 species compared to the pre-ban period, with significant recovery noted in key economic fish species [5]. Group 3: Future Measures and Concerns - The government plans to implement targeted measures and emergency policies to address potential imbalances in fish populations, including expert assessments and tailored management strategies for specific water bodies [4][5]. - The long-term recovery of fish resources is emphasized, with comparisons drawn to the Qinghai Lake fishing ban, which has shown slow progress over 24 years [4].