Abstract: Studies were made on the transparency, the vertical distribution of light intensities and the light compensation depth of submerged macrophyte at the 15 monitoring sections in Lake Dianchi. The transparency in Caohai(the interior of Dianchi) and the exterior of Dianchi were respectively 25-30 cm and 35-40 cm. At the everysection, the light intensity decline as the depth increases, showing negative index correlation, its general formule being I_t=I₀e^-at.The light compensation depth of submerged macrophyte in Caohai and the exterior of Dianchi were less than 100 cm and 150 cmrespectively, much shallower than the actual water depth. The transparency is linear possitive correlation with the light compensation depth in Lake Dianchi. The values of transparency necessary to restorethe biodiversity of submerged macrophyte at different depths are also reported in this study.

Key words: submerged macrophyte, light compensation depth, transparency lake

摘要： 报道了滇池15个监测断面透明度和不同水深的光照强度，以及借助于沉水植物群落昼夜光补偿点所得到的沉水植物光补偿深度。滇池草海透明度为25～30cm，外湖为35～40cm。每个监测断面，随着深度的增加，光照强度呈负指数式衰减，其通式为I_t=I₀e^-αt。滇池沉水植物光补偿深度相当小，其中草海光补偿深度小于100cm，外湖小于150cm，大大小于实际水深。滇池透明度与光补偿深度呈线性正相关。报道了欲恢复沉水植物多样性，不同深度水域所必须具有的透明度数值。

关键词: 沉水植物, 光补偿深度, 透明度, 湖泊