洪泽湖生态安全评估研究

【作者】 张磊；

【导师】 胡海波；

【作者基本信息】 南京林业大学 ， 水土保持与荒漠化防治， 2015， 博士

【摘要】 湖泊生态安全是指在人类活动影响下湖泊生态系统的完整性和生态健康状况,为人类稳定提供生态服务功能和免于生态灾变的持续状态。洪泽湖是我国第四大淡水湖泊,是南水北调东线工程的重要调蓄水库。近几十年来,伴随着经济的快速增长和城市化的推进,洪泽湖不仅水质下降,而且其生态系统功能退化,生态服务功能(如鱼类产卵场、生物栖息地、游泳和娱乐等)严重受损,湖泊生态系统健康受到威胁。本文以湖泊生态安全评价方法的分析为基础,以洪泽湖及其流域为案例,采用现场调查与历史数据整理,从湖泊水生态系统健康、生态系统服务功能、生态灾变、流域社会经济发展影响等四个方面分别开展“4+1”评价,并进行相互印证,对洪泽湖生态系统安全状态进行了综合定量评价,结果表明：(1)2012年洪泽湖全湖生态安全指数SESI为62.80,生态安全尚处于“安全”水平,近年来处于一个相对稳定的状态,但较20世纪80年代有明显下降。(2)洪泽湖生态系统综合健康状况总体呈良好态势,处于中等水平,但生态系统综合健康指数呈现递减趋势。(3)洪泽湖生态系统服务功能价值与上世纪80年代湖泊服务功能价值相比保留了75%,生态产品供给和生态系统调节功能呈现退化趋势,且洪泽湖为过水性湖泊,换水周期短,对面源污染物的阻截和水质净化服务功能比一般蓄水型湖泊湿地偏弱。(4)洪泽湖上游来水水质对洪泽湖发生灾变事件具有决定性影响,成子湖区受水文情势影响具有发生局部“水华”的条件,湖区生态环境存在一定的灾变风险。(5)洪泽湖流域影响综合压力指数为3级,说明流域系统结构敏感性强,社会经济发展对其影响压力较大,接近生态阂值。(6)洪泽湖流域必须严格控制入湖污染物,加强湿地保护,实施流域产业绿色化转型升级,开展生态渔业建设和实施流域生态安全综合管理,逐步提高湖泊生态安全水平。更多还原

【Abstract】 Lake ecological security refers to a constant state of the integrity and eco-health of lake under the influnce of the activities of human being, which steadily provides the ecological service function for human and avoids ecological catastrophe. Hongze lake is an important regulating reservoir of the Eastern Route of South-to-North Water Transfer Project as the fourth largest fresh-water lake in China, not only the water quality of Hongze lake declined, but also the function of ecosystem degraded with the rapid growth of the economy and the rapid urbanization for decades. Thus, the ecological service function of Hongze lake such as fishing spawning areas, habitats, swimming and entertainment venues, etc had been seriously damaged,and the ecosystem health is now being threatened. In this paper, we chose the Hongze lake and its watershed as the research object. In order to make an integrated quantitative evaluation on the ecological security of Hongze lake, the evaluation was conducted from four aspects and a cross-validation on the basis of the lake ecological security evaluation method by historical data collection and field investigation, that is “4+1” evaluation model, including lake water ecosystem health, ecosystem service function, ecological catastrophe and socioeconomic development. The main conclusions in this paper are as follows:(1) The value of ecological security index(SESI) of Hongze lake was 62.80 in 2012, the status of ecological security was still in its "safey" level. In recent years, the ecological security of Hongze lake was in a relatively stable state, however, it had obviously decreased compared with the status in 1980 s.(2) The integrated ecosystem health of Hongze lake overall was in a good condition and the medial level, but the comprehensive ecosystem health index showed a decreasing trend.(3) The value of ecosystem service function of Hongze lake retained only 75% compared with Compared with the 1980 s, the functions of ecological products supply and ecosystem regulation showed a trend of deterioration. In addition, the functions of non-point source pollutants interception and water quality purification of Hongze lake were weaker than ordinary water-carrying lakes and wetlands.(4) The upriver water quality of Hongze lake has a decisive impact on the incidents of ecological disaster of Hongze lake. Local area of Chengzi lake has the condition of breakout of algal bloom affected by the hydrological regimes, and there is a risk of catastrophe certainly for the ecological environment of this lake(5) The comprehensive pressure index of Hongze lake was level three, which indicated that the basin system structure is rather sensitive.The impact of socioeconomic development will bring heavy pressure which has nearly reached the ecological threshold to Hongze lake.(6) In order to improve the ecological security of Hongze lake, the pollution into Hongze lake and its watershed must be controlled strictly, the protection of wetland must be strengthened, the greenization of industry transformation and upgradation must be implemented,the development of ecological fishery and the comprehenseive management of watershed ecological security must be carried out.更多还原