扩大有机肥源是夺取当季作物高产和改良土壤的重要一环。绿萍是一种水生绿肥,具有固氮(通过体内共生蓝藻的作用)及繁殖力强的特性。我国稻田养萍的历史相传已有两个世纪(浙江省农科院土壤肥料研究所编,1976),浙江、福建、四川、广东、广西部分地区早有利用绿萍作为肥料的习惯。近年来,由于耕作制度的改革、复种指数的提高以及高 The expansion of organic fertilizer sources is an important part of seizing the crop’s high yield and soil improvement. Lvping is a aquatic green manure with nitrogen fixation (through the role of symbiotic cyanobacteria in the body) and fertility characteristics. The history of rice paddies in our country has been passed down for two centuries (Institute of Soil and Fertilizer, Zhejiang Academy of Agricultural Sciences, 1976). In Zhejiang, Fujian, Sichuan, Guangdong and Guangxi, the history of using green asparagus has long been used as a fertilizer. In recent years, due to the reform of farming system, the improvement of multiple cropping index and high