Investigation of the factor that declines Charales and the restoration method for the conservation of lacustrine ecosystems

为了保护被认为是最有效的水质控制的Charales，我们开发的方法来量化的植被面积和沉水水生植被的生物量与多波束声纳。以布朗轮藻为实验材料，研究了除草剂阿特拉津<-6>和DCMU<-8>对布朗轮藻光合作用和生长的影响。通过照片判读和种子分析，我们发现，目前没有轮藻目的湖泊曾经居住着几种轮藻，并且有轮藻时的透明度明显高于现在。

For the conservation of Charales which is regarded to be most effective in water quality control, we developed the method to quantify the vegetated area and the biomass of submerged aquatic vegetation with a multi beam sonar. Based on the laboratory experiment using Chara braunii, we proved that herbicides, Atrazine more than 10^<-6> M and DCMU more than 10^<-8> M, affected the photosynthesis and algal growth. Using photographic interpretation and seeds analysis, we found that the lake without Charales at present used to be inhabited with several species of Chara and the transparency at the time with Chara was significantly higher than present.