目前,我国湖泊富营养化及蓝藻水华问题十分突出,国家高度重视湖泊的生态环境保护.自“九五”以来,国家就投入太湖、巢湖、滇池“老三湖”等重污染湖泊的治理,但成本巨大,且历经近30年才初见成效.按照湖泊污染程度,湖泊治理与保护可分为“污染治理型”“防治结合型”“生态保育型”3大类.“老三湖”的治理是典型的“先污染、后治理”的模式,水质较好湖泊主要属于生态保育型湖泊,因此,“老三湖”治理模式不适用于水质较好湖泊的保护.本文系统总结了我国水质较好湖泊优先保护理念的形成和水质较好湖泊专项实施的历程.根据水质较好湖泊的特点,及其生态系统退化与修复的一般过程,提出了水质较好湖泊保护的基本思路.从热力学角度,阐明了氮磷营养盐输入湖泊生态系统中是熵增过程,也是湖泊生态系统退化的根本原因,湖泊氮磷污染负荷源头控制是关键.湖泊流域生态安全格局是确保湖泊生态系统健康的基础,从景观生态学角度,阐明了优化湖泊流域水土资源利用、优化发展模式是减轻湖泊环境压力的重要途径.在浅水湖泊生态系统,以沉水植物占优势的“清水态”和以浮游植物占优势的“浊水态”转换过程不是沿着同一条途径,存在上临界阈值和下临界阈值,水生态修复过程表现出一种迟滞的现象.从湖泊水生态系统稳态转换理论角度,阐明了湖泊生态修复工程应在湖泊生态系统发生退化转变之前实施,才能获得较高的环境效益.通过国家财政专项对81个水质较好湖泊的支持,既能促进湖泊流域经济社会发展,又能确保湖泊水环境质量变好,湖泊水生态系统逐步改善.建议加强不同类型湖泊保护模式的总结,深入对水质较好湖泊生态系统演替理论和保护技术研究,支撑国家系统开展水质较好湖泊保护.;At present, the problems of lake eutrophication and cyanobacterial blooms in China are still very prominent and the state attaches great importance to the ecological environment protection of lakes. Since the Ninth Five-Year Plan, the government has started to control the old three lakes of Lake Taihu, Lake Chaohu and Lake Dianchi, but it has spent huge treatment costs. After nearly 30 years of governance, the trend of further deterioration of water quality in the old three lakes was initially curbed. According to the degree of lake pollution, lake control and protection can be divided into three types:pollution control type, combined prevention and control type and ecological conservation type. The governance of the old three lakes was a typical pollution first, treatment later model, and the lakes with better water quality mainly belong to ecological conservation type, so the treatment model for old three lakes is not suitable for the protection of lakes with better water quality. This paper systematically summarizes the formation of the concept of priority protection of lakes with better water quality in China and the implementation history of special lakes with better water quality. According to the characteristics of the lake with better water quality and the general process of ecosystem degradation and restoration, the basic idea for the protection of the lakes with better water quality was put forward. From a thermodynamic perspective, the entropy increase process of nitrogen and phosphorus nutrient input into the lake ecosystem was analyzed, revealing the root cause of the degradation of the lake ecosystem and the importance of source control of nitrogen and phosphorus pollution load into lakes. The ecological security pattern of lake basin is the basis for ensuring the health of lake basin ecosystem. From the perspective of landscape ecology, this paper clarifies that optimizing the use of soil and water resources in lake basin and optimizing the development pattern are important ways to reduce the environmental pressure on the lake. The transition process of the clear water state dominated by submerged plants and the turbid water state dominated by phytoplankton in shallow lake ecosystems is not along the same pathway. There are upper and lower critical thresholds, and the aquatic ecological restoration process shows a hysteresis phenomenon. From the theory of steady-state transformation of lake water ecosystem, we clarified that the lake ecological restoration project should be implemented before the degradation transformation of lake ecosystem to obtain higher protection benefits. The support of 81 lakes with better water quality through the special national finance can not only promote the economic and social development of the lake basin, but also ensure the improvement of the quality of the lake water environment and improvement of lake water ecosystem. We recommended to strengthen the summary of different types of lake protection models, conduct in-depth research on the theory of ecosystem succession and protection technology of lakes with better water quality, and support the state to carry out the protection of lakes with better water quality systematically.
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