Core Viewpoint - The article highlights the successful implementation of cross-regional environmental protection regulations for the Wanfeng Lake, leading to significant improvements in water quality and ecological restoration in the area [1][3][5]. Group 1: Environmental Issues - Wanfeng Lake has faced severe ecological challenges due to unregulated fish farming and poor inter-regional governance, resulting in water quality deterioration and eutrophication [3][5]. - In 2017, inspections revealed that the fish farming area exceeded planned limits by 3.93 times, with daily feed inputs surpassing 5,000 tons, leading to a significant increase in nitrogen and dissolved oxygen levels [3]. Group 2: Legislative Actions - The "Wanfeng Lake Protection Regulations" were enacted on January 1, 2023, providing a legal framework for environmental protection in the region [3][5]. - Additional regulations from neighboring regions, including the "Guizhou Wanfeng Lake Protection Regulations" and "Qujing Wanfeng Lake Protection Regulations," were also implemented on the same date [3]. Group 3: Collaborative Efforts - A joint enforcement command was established in March 2022 among the three provinces, focusing on cross-regional environmental law enforcement and emergency response [5]. - As of now, significant actions have been taken, including the removal of 4.3 million square meters of illegal fish farming structures and the closure of three non-compliant enterprises [5]. Group 4: Water Quality Improvement - Following the implementation of protective measures, the water quality in Wanfeng Lake has improved to Class I, meeting drinking water standards, marking the best water quality recorded [3][5]. - By May 2025, the water quality maintained a Class II standard, with transparency exceeding 2.5 meters, indicating a gradual recovery of aquatic biodiversity [5].

Core Viewpoint - The article discusses the long-term efforts and challenges in the ecological restoration and pollution control of Taihu Lake, highlighting the transition from severe pollution to improved water quality over 30 years, with a focus on collaborative governance and innovative solutions to address the complex pollution issues [1][4][19]. Group 1: Water Quality Improvement - Taihu Lake's water quality has improved from Class V to Class III over 30 years, establishing itself as a benchmark for large lake nutrient management internationally [1]. - The average depth of Taihu Lake is 1.9 meters, making it a shallow lake with limited self-purification capacity, which complicates pollution management [2][3]. - In 2022, the population in the Taihu basin accounted for 4.8% of the national total, and the regional GDP represented 9.8% of the national GDP, indicating significant economic activity in the area [3]. Group 2: Pollution Sources and Challenges - The shallow nature of Taihu Lake allows sunlight to reach the bottom, promoting blue-green algae growth, which is exacerbated by industrial pollution and urbanization in the surrounding areas [2][3]. - The 2007 blue-green algae outbreak highlighted the complexity of pollution sources, leading to a shift in focus from ecological restoration to source control and pollution interception [4][6]. - The Taihu basin has faced severe pollution, with 67% of monitored points classified as inferior Class V water quality, indicating a critical need for effective pollution control measures [3]. Group 3: Governance and Collaborative Efforts - The governance of Taihu Lake has evolved from fragmented management to a more coordinated approach, with the establishment of inter-agency collaboration and joint initiatives among cities [15][16]. - The introduction of the Taihu Lake water pollution prevention office in 2009 marked a significant step towards unified management of water quality across different jurisdictions [16]. - Recent initiatives include the establishment of cross-regional cooperation mechanisms and joint law enforcement efforts to tackle pollution effectively [17][18]. Group 4: Economic Transformation and Sustainable Development - The shift from high-pollution industries to green, low-carbon economic models is crucial for the sustainable development of the Taihu region, with significant reductions in polluting industries [12][13]. - The transformation of Zhou Tie Town from a chemical industry hub to an eco-friendly area demonstrates the potential for economic growth while prioritizing environmental protection [12][13]. - By 2024, the region has seen a stable GDP growth rate while improving water quality, showcasing a successful model of balancing economic development with ecological sustainability [14].