【摘要】 水下光环境是制约沉水植物定植和浅水湖泊生态恢复的关键因子之一。以往研究较少定量确定水环境因子在水质-水下光环境-沉水植物定植关系中的贡献特征，并缺乏对各水环境因子关联性的综合考虑，也未明确面向沉水植物定植需求的参数阈值。研究以典型国家湿地自然保护区为研究对象，测定了光合有效辐射、光衰减系数、真光层深度、透明度、总悬浮物、叶绿素a、总氮和总磷等指标，构建了水下光衰减系数模拟模型，解析了水环境因子空间分布特征，量化了水环境因子对光衰减的贡献率，确定了主要参数的阈值。结果显示：研究区的光衰减系数平均为（10.31±3.76 ） m^-1，真光层深度[（0.53±0.24） m]低于平均水深[（0.94±0.29） m]，并呈西低东高的异质性；总悬浮物和叶绿素a是主要的直接影响因子，总氮是主要的间接影响因子；为实现平均水深条件下沉水植物的有效定植，真光层深度需≥0.94 m，对应的透明度需≥0.41 m，光衰减系数需≤4.95 m^-1，叶绿素a需≤3.8??g/L。更多还原

【Abstract】 The underwater light environment is one of the key limiting factors for the colonization of submerged macrophytes and the ecological restoration of shallow lakes. Previous studies have rarely quantitatively determined the contribution characteristics of aquatic environmental factors in the relationship between water quality, underwater light environment, and submerged macrophyte colonization. They have also failed to comprehensively consider the correlations among various aquatic environmental factors or to clarify the parameter thresholds that meet the requirements for submerged macrophyte colonization. Taking a typical national wetland nature reserve as the study area, this study measured indicators including photosynthetically active radiation, light attenuation coefficient, euphotic depth, water transparency, total suspended solids, chlorophyll-a, total nitrogen, and total phosphorus. A simulation model of the underwater light attenuation coefficient was established, the spatial distribution patterns of aquatic environmental factors were quantitatively analyzed, the contribution rates of aquatic environmental factors to light attenuation were quantified, and the thresholds of key parameters were determined. The results showed that the average light attenuation coefficient in the study area was（10.31±3.76） m^-1; the euphotic depth [（0.53±0.24） m] was lower than the average water depth [（0.94±0.29） m], exhibiting a heterogeneous pattern of being shallower in the west and deeper in the east. Total suspended solids and chlorophyll-a were the main direct influencing factors, while total nitrogen was the main indirect influencing factor. To achieve effective colonization of submerged macrophytes under the condition of average water depth, the euphotic depth should be ≥ 0.94 m, corresponding to the water transparency ≥ 0.41 m, light attenuation coefficient ≤ 4.95 m^-1, and chlorophyll-a ≤ 3.8 ??g/L.更多还原