基于河湖长制的杞麓湖岸线划定管控

Shoreline Delimited and Management of Qilu Lake Based on the River(Lake)Chief System

实施河(湖)长制后,云南省的岸线边界、保护范围等尚未划定,给湖泊岸线空间管控带来诸多困难。以杞麓湖为例,采用小波函数和Gini系数分析湖泊水位变化的周期性、均衡性特征,以水位保证率法、兴利及洪水调节确定生态水位、临水边界及外缘边界线。(1)杞麓湖水位具有10、15和25 a的振荡周期,以25 a为第一主周期,呈不显著的上升趋势,存在1969、2009年两处突变点,以2009年最突出。Gini系数和降水盈亏指标揭示的水位变化特点,与小波分析结果一致。(2)最小生态水位为1793.72~1794.90 m,在5、6月最低,12月最高;适宜生态水位1794.35~1795.39 m,最佳生态水位1795.22~1796.21 m。(3)综合湖泊水生态修复、流域水资源配置规划及供水安全保障等因素,确定临水边界线为1793.92 m;综合湖泊水生态修复的最佳生态水位、兴利防洪等因素,湖岸的外缘边界线为1796.62 m,表明湖泊保护条例规定的运行水位能够适应岸线划定管控要求。(4)基于GF-3号卫星遥感影像,经空间叠加分析划定岸线空间为保护区,从责任传导、治理困难、支撑手段、社会参与等方面分析湖岸线管理存在的问题,制定湖岸线管控基本规则和要求。

After the implementation of the river(lake)chief system,the shoreline boundary and protection scope of Yunnan Province have not been delimited,which brings many difficulties to the control of lake shoreline space.Taking Qilu Lake as an example,the characteristics of periodicity and equilibrium of lake water level change are analyzed by wavelet function and the Gini coefficient,and the ecological water level,water boundary and outer boundary are determined by the method of water level guarantee rate,flood regulation and development.(1)The water level of Qilu Lake has oscillation periods of 10,15 and 25 years,with 25 years as the first main period,showing an insignificant upward trend.There are two abrupt changes in 1969 and 2009,with the most prominent one in 2009.The characteristics of water level change revealed by the Gini coefficient and precipitation fluctuation index are consistent with the results of wavelet analysis.(2)The minimum ecological water level ranges from 1793.72 to 1794.90 m,reaching the lowest in May and June while reaching the highest in December.The suitable ecological water level varies between 1794.35 and 1795.39 m,and the optimal ecological water level varies between1795.22 and 1796.21 m.(3)The boundary of the water is 1793.92 m when lake water ecological restoration,basin water resources allocation planning and water supply security are considered.The optimal ecological water level of lake water ecological restoration and the factors of promoting flood control are taken into account,the outer boundary of the lake bank is 1796.62 m.The results indicate that the operating water level stipulated by the Lake Protection Regulations can meet the requirements of shoreline demarcation and control.(4)Based on a spatial superposition analysis of the GF-3 satellite images,the shoreline space is designated as a protected area.This paper analyzes problems in shoreline management from the perspectives of responsibility transmission,supported means and social participation,and formulates the basic rules and requirements of shoreline management and control.