鄂东南5个典型湖泊的水体光学特性研究

为了探究水体光学特性的时空变化特征及影响因素，于2018—2019年对鄂东南5个典型湖泊（仙岛湖、梁子 湖、网湖、策湖和青山湖1号）进行了周年调查；通过分析光学衰减系数（Kd）等重要水体光学参数，得到了各湖泊光合 有效辐射衰减特征及影响因子，可为该地区富营养化湖泊的水生植被修复提供参考。结果表明：（1）鄂东南5个典型 湖泊之间的透明度、悬浮物、叶绿素a差异极显著（P<0.01）。（2）仙岛湖和梁子湖的溶解性有机物浓度较低，年均值分别 为（1.38±0.39）、（2.36±0.92）m-1，与其他湖泊差异极显著（P<0.01）。（3）年均光学衰减系数的空间分布规律为：仙岛湖 （ 0.36±0.21）m-1]<梁子湖（ 1.81±0.89）m-1]<青山湖1号（ 3.77±1.89）m-1]<策湖（ 4.40±1.90）m-1]<网湖（ 4.70±2.54）m-1]， 各湖泊之间存在极显著差异（P<0.01）。（4）仙岛湖光学衰减系数的主要影响因子是溶解性有机物，梁子湖和网湖则主要 受悬浮物影响，溶解性有机物和叶绿素a是造成策湖和青山湖1号水体光学衰减系数较高的重要原因，其中以溶解性有 机物为主。（5）各湖泊的真光层深度与透明度均呈现出极显著相关性（P<0.01），透明度在一定程度上可以反演真光层深 度，也可为沉水植物恢复区域划分提供依据。

Optical Properties of Five Typical Lakes in Southeastern Hubei Province

In recent years, eutrophication of some lakes in southeast Hubei Province has intensified due to industrial and agricultural production and pollution from domestic sewage, and the need for ecological restoration is urgent. In this study, five typical lakes (Xiandao, Liangzi, Wanghu, Cehu and Qingshan Lakes) in southeast Hubei Province were selected for study, and we explored the temporal and spatial vari? ation of optical properties in the five lakes by analyzing the light attenuation coefficient (Kd), euphotic zone depth (Zeu), photosynthetically active radiation (PAR) and other optical parameters. The factors influ? encing the variation in optical properties were also identified. The objectives were to provide a reference for aquatic vegetation restoration of the eutrophic lakes in this area. The study was based on a seasonal field investigation and water quality monitoring in the five lakes during autumn and winter of 2018, and spring and summer of 2019. Results show that: (1) The Secchi depth (SD), suspended solids (SS) and chlorophyll-a (Chl-a) of the five lakes were all significantly different (P<0.01). (2) The concentrations of dissolved organic matter (DOM) in Xiandao Lake and Liangzi Lake were relatively low, with annual mean values of (1.38±0.39) and (2.36±0.92) m-1, respectively, significantly different from those in other lakes (P<0.01). (3) The spatial distribution of Kd among lakes also varied significantly (P<0.01), with the following annual averages: Xiandao Lake (0.36±0.21) m-1] < Liangzi Lake (1.81±0.89) m-1]